JP6855046B2 - Electrodes for measuring brain activity, head-mounted devices and brain activity measuring systems using the electrodes - Google Patents

Description

The present invention relates to an electrode for measuring brain activity used for measuring brain activity, a head wearing device using the electrode, and a brain activity measuring system.

Measurement of brain activity such as electroencephalogram (electroencephalogram), magnetoencephalography, and cerebral blood flow is widely performed in research such as medical diagnosis and cognitive science, and in recent years, industrial applications such as product evaluation and marketing in the industrial field have been promoted. Has been done. For industrial application, it is important that a brain activity detection system (for example, an electroencephalograph) can be easily attached to a subject to ensure reliable measurement. In order to measure brain waves, the electrodes need to be grounded to the subject's scalp. There are roughly two types of electrode attachment methods: wet type and dry type.
The wet type electrode (hereinafter referred to as a wet electrode) is a type in which a conductive paste, gel, physiological saline, or the like is applied onto the electrode at the time of use. As a method of setting the wet electrode, for example, taking a silver / silver chloride dish electrode as an example, the hair at the place where the electrode is installed is scraped off to expose the scalp, and then sebum on the scalp is removed with alcohol or the like, and a conductive paste is used. Is applied and the electrodes are placed on the scalp with a paste. However, in such an embodiment, 1) it is necessary to apply a paste or the like, which is troublesome to attach the electrodes, 2) the paste remains on the subject's head after measurement and becomes dirty, and 3) a rash or rash caused by alcohol or the paste. It is not realistic for industrial application because there are problems such as risk.
On the other hand, a dry electrode (hereinafter referred to as a dry electrode) can be measured without applying a conductive paste, gel, physiological saline, etc., and is therefore considered to be suitable for industrial application. Several shapes of dry electrodes have been proposed. Patent Document 1 is given as an example of such a dry electrode. Patent Document 1 is a metal dry electrode (inverted U-shaped metal member 2).

Japanese Unexamined Patent Publication No. 2006-94979

However, it is difficult to process with a metal dry electrode, it is difficult to produce electrodes having various shapes, and the processing cost is high. In addition, since it is made of metal, it is heavy, so if many electrodes are attached, the head becomes heavy, and since it is hard, it may cause pain when attached. On the other hand, when the dry electrode is made of synthetic resin, the problem of such a metal dry electrode does not occur.
However, when it is made of synthetic resin, for example, the following problems arise.
1) Generally, a dry electrode made of synthetic resin is inferior in conductive performance to a dry electrode made of metal.
2) When making an electrode from resin, it is first considered to use a single conductive resin. However, the performance required for an electrode is not only conductivity, but also the softness of the electrode, the mechanical strength of the electrode (for example, it cannot be used if it is brittle), and whether it is industrially feasible (generally, conductive resin materials There are problems such as high price).
3) If an electrode can be produced by mixing a conductive substance with a resin as a base material, the problems of 1) and 2) can be considerably solved. However, when the conductive substance is mixed with the base material, the conductivity of the entire dry electrode made of the synthetic resin is inevitably lower than that of the original conductive substance itself. Therefore, there has been a demand for a resin electrode that can exhibit sufficient conductivity as an electrode even if an electrode is manufactured by mixing a conductive substance with a resin as a base material.

In order to solve the above-mentioned problems, in the first means, the scalp grounding portion is made of a synthetic resin material in a brain activity measuring electrode provided with a tip portion having a scalp grounding portion for contacting the scalp. The synthetic resin material contains a group of fibrous conductive substances.
With this configuration, even if it is made of synthetic resin, it will have sufficient conductivity, so it is possible to obtain measurable electrical information as brain activity when using electrodes for measuring brain activity. it can.
The reason is that a group of fibrous conductive substances having a large aspect ratio is contained in order to create a path for conducting electricity, so that the conductivity can be effectively increased. In addition, it can be expected that the probability of contact between fibers will increase by making them fibrous. Further, by making the conductive substance group to be mixed in this way fibrous, it is possible to give directionality to the flow of electricity as compared with the case where it is not fibrous, and electricity can flow in the resin having a large resistance. It is thought that this is because the amount of electricity is reduced, which makes it easier for electricity to flow. Further, by making it fibrous, the conductivity can be effectively increased with a small content, and the content of the conductive substance group can be reduced, so that the original softness and strength of the synthetic resin (for example, it cannot be used if it is brittle). ) Can be retained. Further, since the conductive material is generally expensive, it is advantageous in industrial application that the cost for manufacturing the electrode can be reduced.

Here, "brain activity" is generally measured as a magnetic field generated by the flow of an electric current from the outside, a potential difference (voltage difference) at different positions, oxygenated hemoglobin, and near-infrared light amount difference due to absorption of globin etc. for deoxidization. Therefore, as the "electrode for measuring brain activity" of the present invention, for example, an electrode for measuring current (change in potential difference) accompanying nerve activity in the brain, or a magnetic field for changing current due to brain activity. Electroencephalogram (magnetoencephalography) measurement electrodes and changes in cerebral blood flow (oxygen cahemoglobin, deoxidized hemoglobin amount, etc.) associated with brain activity are measured as changes in the amount of near-infrared light received. It is often used as a probe for near-infrared spectroscopic measurement. In particular, when recording brain activity as a potential difference (voltage difference) (electroencephalogram measurement), a dry electrode is preferable because it can reduce the measurement burden on the subject.
Here, "contact with the scalp" means brain activity so that when measuring brain activity using electrodes for measuring brain activity, the brain activity can be acquired as data such as potential difference, magnetic field change, and amount of received near infrared rays. The measurement electrode is in close proximity to the scalp. It is preferable that the electrodes for measuring brain activity are in close contact with the scalp, but they do not necessarily have to be in close contact with each other. I do not care.
Further, "fibrous" refers to a shape having a sufficient length compared to the diameter and a large aspect ratio, and is a form in which the axial direction is sufficiently long with respect to the radial direction, such as hair, and is straight. May be curly.
The "conductive substances" include, for example, gold, silver, platinum, copper, nickel, aluminum, carbon black, carbon nanotubes, carbon nanohorns, carbon nanobrushes, polythiophene, polyacetylene, polyaniline, polypyrrole, etc. PEDOT / PSS and the like. In particular, gold, silver, PEDOT / PSS, etc. are desirable because they have a small load on the living body. Further, the conductive substance group has conductivity, for example, if it is fibrous, it may be directly contained in the synthetic resin material, and for example, it has conductivity and is not fibrous. In this case, the synthetic resin material may be contained as a fibrous conductive substance group by coating the fibrous base material with the conductive substance group.
The "fibrous conductive substance group" is a conductive substance having a sufficient length (large aspect ratio) compared to the diameter, and is a non-filamental fibrous conductive substance group and a filamentous fibrous conductive substance. Includes a group of substances. For example, the non-filamental fibrous conductive substance group has an average radial size of about 1 nm to 100 nm and an average length of about 1 μm to 100 μm. The size and length in the radial direction are small, the fibers do not aggregate with each other, so it is easy to mold, and there is an advantage that a large amount can be contained in the synthetic resin material. For example, the filamentous fibrous conductive substance group has an average radial size of about 1 μm to 500 μm, and the radial size and length are large, so that the conductivity can be effectively increased. .. Here, a group of fibrous conductive substances that are filamentous is particularly preferable, and the average length is, for example, 1.0 mm to 3.0 mm so that the fibers do not get entangled with each other while effectively increasing the conductivity with a small content. That's good.
Here, the "thread-like" refers to a shape in which fibers are twisted by spinning, silk reeling, spinning, or the like, or a shape like a long fiber yarn having a continuous length. For example, the silk length of a typical long fiber yarn is about 1000 m to 1500 m. In the present invention, for example, a group of conductive substances in the form of threads may be cut to about 1.0 mm to 3.0 mm and contained in the synthetic resin base material.
Here, the "synthetic resin" includes a thermoplastic or thermosetting plastic, a synthetic rubber, or a thermoplastic elastomer, and includes, for example, a styrene-based thermoplastic elastomer, an olefin-based thermoplastic elastomer, a urethane-based thermoplastic elastomer, and a vinyl chloride-based resin. Thermoplastic elastomer, polyamide-based thermoplastic elastomer, ester-based thermoplastic elastomer, polyethylene, polycarbonate, polyvinyl chloride, polypropylene, polystyrene, polylactic acid, nylon, polyacetal, modified polyphenylene ether, polyethylene terephthalate, polybutylene terephthalate, polymethylmethacrylate, Polyamide, polyurethane, polyimide, polyester, polyolefin, ABS resin, AS resin, epoxy resin, urea resin, phenol resin, melamine resin, styrene / butadiene rubber, isoprene rubber, silicone resin (silicone rubber), ethylene / propylene rubber, butyl rubber, Chloroprene rubber, acrylonitrile / butadiene rubber, fluororubber, etc.
Further, "containing" is preferably a state in which the fibrous conductive substance is sufficiently and uniformly dispersed in the synthetic resin as a solute. This is because electricity flows smoothly when it is contained in this way.

Further, as a second means, the fibrous conductive substance group is contained only in the tip portion.
As a result, the entire tip that may come into contact with the scalp can be molded with resin, and when using electrodes for measuring brain activity while taking advantage of various advantages of resin (good moldability, flexible composition, etc.). It is possible to obtain measurable electrical information as brain activity in.
Further, as a third means, a portion that does not contain the fibrous conductive substance group is provided in a portion other than the scalp grounding portion.
Further, as a fourth means, a portion that does not contain the fibrous conductive substance group is provided in a portion other than the tip portion.
As a result, it becomes possible to lead the acquired electrical information to a region having good conductivity containing a group of fibrous conductive substances without inadvertently diffusing it, which is advantageous in the design of the electrode.
Further, as a fifth means, the fibrous conductive substance group is made to have a fine form.
As a result, the fibers do not get entangled with each other, and the surface area when the conductive substance group having the same weight is contained is increased, so that electricity flows more smoothly.
Here, the “fine” means that the size in the radial direction is, for example, about 1 nm to 100 nm on average, and the length is preferably about 1 μm to 100 μm on average. When a group of conductive substances in the form of threads is contained, for example, the average length is preferably about 1.0 mm to 3.0 mm.

Further, as a sixth means, a support portion for supporting the tip portion is provided.
As a result, when the electrode is used, the tip portion supported by the support portion can be brought closer to the scalp side to hold the electrode on the support portion side, which is advantageous in the design of the electrode.
Further, as a seventh means, the support portion is made of a synthetic resin material and has a portion that does not contain the fibrous conductive substance group.
This makes it possible to guide the acquired electrical information from the region having good conductivity containing the fibrous conductive substance group to the amplification device without inadvertently diffusing it in the support portion, which is advantageous in the design of the electrode. Is.
Further, as an eighth means, the support portion is provided with an electrode fixing portion.
With such a configuration, the electrode for measuring brain activity can be easily fixed to another member to be fixed. If the electrode is fixed to the base for head mounting, which will be described later, by the electrode fixing portion as the member to be fixed, the electrode mounting work can be simplified. It is preferable to arrange the electrode fixing portion at the base portion (rear) in the direction opposite to the tip portion of the support portion in order to widen the space near the tip portion.

Further, as a ninth means, a conductor was arranged from the scalp grounding portion to a position in the support portion region for mounting the amplification device.
Further, as a tenth means, a conductor was arranged from the tip portion to a position in the support portion region for mounting the amplification device.
As a result, since the conductor is arranged from the grounded portion of the scalp or the tip portion to the position in the support portion region for mounting the amplification device, the acquired electrical information such as the brain potential and the magnetoencephalogram is reliably transmitted. be able to. Here, the "support portion region" broadly refers to a portion included in the support portion inside or on the outer surface of the support portion.
The position in the support portion region for mounting the amplification device may be, for example, an electrode fixing portion. Further, the position may be different from the electrode fixing portion.
Further, as an eleventh means, the conductor is made to be a conductive layer formed on the outer surface of the tip portion and the support portion.
By transmitting electrical information through a thin layered conductor on the outer surface, current flows only on the surface compared to when the entire electrode is transmitted as a conductor, so there is less voltage drop and information deterioration can be reduced. it can. Plating, thin-film deposition, or a dip method is preferable as a means for forming the conductive layer.
Further, as a twelfth means, the conductor is made to be a conductive layer or a conductive wire embedded inside the tip portion and the support portion.
By burying it inside in this way, it is less likely to be affected by the outside, so deterioration of information can be reduced. Further, since the conductive layer or the conductive wire is embedded inside, the conductive layer or the conductive wire is not worn due to the contact between the tip portion and the scalp by the measurement of brain activity, and the decrease in conductivity can be prevented. When the electrode is "embedded inside", a part of the conductive layer or the conductive wire may be exposed to the outside. Conductive layer or conductive wire It is preferable to have an exposed portion for transmitting electrical information to the outside.

Further, as a thirteenth means, the fibrous conductive substance group is contained in the synthetic resin material in which the conductor is embedded.
Since the conductor is embedded in the synthetic resin material, the conductivity can be improved by including the fibrous conductive substance group in the embedded synthetic resin material. Any material in which the conductor has the property of permeating the molten resin inside is particularly preferable.
Further, as a fourteenth means, the scalp grounding portion is made of a flexible material.
If the scalp grounding portion is made of a flexible material, the electrodes can easily adhere to the scalp and can obtain as much electrical information as possible such as brain potential and magnetoencephalography. In addition, since the scalp grounding portion bends according to the shape of the head, there is a possibility that a scalp grounding portion that is not in contact or a scalp grounding portion that is not in firm contact may occur when there are a plurality of scalp grounding portions. The sex becomes low.
A "flexible material" is, for example, a material that is flexible and deforms when bent or pushed under external pressure, but returns to its original shape when the pressure is removed. For example, synthetic rubber. And thermoplastic elastomers and / or foamed plastics, such as styrene-based thermoplastic elastomers, olefin-based thermoplastic elastomers, urethane-based thermoplastic elastomers, vinyl chloride-based thermoplastic elastomers, polyamide-based thermoplastic elastomers, ester-based thermoplastic elastomers, and styrene. -Butadiene rubber, isoprene rubber, silicone rubber, ethylene / propylene rubber, butyl rubber, chloroprene rubber, acrylonitrile / butadiene rubber, fluororubber, flexible polyurethane foam, polyethylene foam, polystyrene foam, polypropylene foam, etc. are preferable. In particular, a flexible material with elasticity close to that of the skin is desirable because it has high adhesion to the scalp and does not cause pain due to wearing.
It is not only the scalp grounding portion that is composed of the "flexible material", but the entire tip portion may be composed of the flexible material. Further, the entire electrode may be made of a flexible material. On the other hand, the support portion side may be made of a hard material, and the tip end side may be made of a material more flexible than the support portion side. This is because the adhesion is improved only on the side that comes into contact with the scalp, and the support portion side is hard and does not deform, so that the electrodes can be firmly supported. A "hard material" is, for example, a material that is not flexible and does not deform even when bent or pushed under external pressure.
Further, as a fifteenth means, the tip portion is made of a flexible material.
As a result, as in the case of the fourteenth means, the electrodes easily adhere to the scalp, and it is possible to obtain as much electrical information as possible such as brain potential and magnetoencephalography. In addition, the scalp ground contact portion is bent more according to the shape of the head than the thirteenth means.

Further, as the 16th means, the conductive substance group contained in the synthetic resin material is a mixture of the fibrous conductive substance group and the conductive substance group having at least one of powdery and granular forms. It was. By mixing a group of conductive substances whose morphology is different from that of the group of fibrous conductive substances, the density of the group of conductive substances can be increased, so that a very small brain potential obtained from the brain can be efficiently (that is, that is). Can be communicated (without deterioration).
Here, "powder-like" is a fine form that is not fibrous. “Granular” is a fine substance having a particle size larger than that of powder, and is a form having a larger outer peripheral area of one unit than that of powder. In reality, it is not possible to clearly classify the two because it is not clearly determined from which size the powder to be granular. If one unit can be discriminated visually, it is granular.
If the entire electrode is made of such a material, sufficient conductivity can be obtained even if the synthetic resin material is used as a base, and a plastic material having good moldability and low cost can be used.

Further, as the 17th means, a conductive synthetic resin was used as the electrode material.
If the entire electrode is made of such a material, it becomes possible to obtain better electrical information in cooperation with the fibrous conductive substance group. As the "conductive synthetic resin", for example, polythiophene-based, polyacetylene-based, and polyaniline-based plastics are preferable.
Further, as an eighteenth means, the support portion side is made of a hard material, and the tip end side is made of a material more flexible than the support portion side.
As a result, the adhesion of only the side that comes into contact with the scalp is improved, and the support portion side is hard and does not deform, so that the electrodes can be firmly supported. "Hard material" and "flexible material" are synonymous with the above. Not all the support side must be made of hard material, and not all the tip side must be made of flexible material.
Further, as a nineteenth means, the conductive substance group is formed by coating the base material with a conductive material. Since the material cost of the conductive material is high, when it is desired to use the conductive material that exhibits suitable conductivity as the conductive substance group, the conductive material can be used as the conductive substance group without using a large amount of the conductive material. The material can be made conductive. Further, when the conductive material cannot be easily produced in the fiber shape, it can be produced in the fiber shape by coating the base material in the fiber shape, so that the choice of the conductive material can be expanded.
The "base material" includes, for example, plant fiber, animal fiber, synthetic fiber, and inorganic fiber in the case of fiber, and includes, for example, cotton thread, hemp thread, silk thread, wool, rayon, cupra, nylon, polyester, polyurethane, carbon fiber, and glass. Fiber, stainless steel, copper and aluminum are good. By containing the fiber coated with the conductive material, the electrode base material is a flexible material, and it is possible to easily follow the deformation even when it is deformed by receiving pressure from the outside. In addition, conductive fibers have the effect of increasing bulk, and the amount of conductive substances used can be reduced to reduce costs.
Further, as a twentieth means, the outer surface of the scalp ground contact portion is formed so as to be a rough surface.
The "rough surface" is, for example, an uneven surface of 0.5 mm or less. The rough surface may be formed not only on the scalp ground contact portion but also on the entire tip portion. Further, the entire electrode may be composed of a rough surface.
This increases the contact area with the scalp and makes it easier to obtain electrical information from the brain. Further, when the conductive layer is formed on the ground contact portion of the scalp by the dip method, the coating agent constituting the conductive layer is likely to stay in the groove forming the rough surface, so that the conductive performance is maintained. By making the unevenness of the rough surface 0.5 mm or less, dirt can be easily wiped off, so that it is easy to clean. The rough surface may be provided with, for example, fine irregularities, fine streaks, or fine vertical and horizontal grooves.

Further, as a 21st means, the scalp ground contact portion is made to be composed of one or a plurality of protrusions.
With such a configuration, even in a subject having a lot of hair, the protrusions can avoid the hair and come into contact with the scalp. When there are a plurality of protrusions, it is preferable to arrange them so as to be symmetrical (line symmetry or rotational symmetry) in a plan view.
Further, as a 22nd means, the protrusion is made to have a spherical crown shape.
It is a conic-section, that is, a shallow hill-shaped solid that has a shape similar to that of a quadratic curve in which the outer shape of all cross sections passing through the apex is convex upward. With such a shape, it becomes easy to avoid the hair and bring the apex portion into contact with the scalp. In particular, the crown shape is preferably one at the scalp grounding portion of one electrode.
Further, as a 23rd means, the scalp grounding portion is configured to be curved so as to be convex outward. This is intended for shapes other than the crown shape, such as conical shapes and almond shapes, which are not necessarily spheres. With such a shape, it becomes easy to avoid the hair and bring the apex portion into contact with the scalp. In particular, it is preferable that there is one such scalp grounding portion per electrode.

Further, as a twelfth means, the electrode for measuring brain activity according to any one of means 1 to 23 is attached to a base for wearing the head so that the tip portion faces the head side when the subject is worn. The head-mounted device is configured.
A specific head-mounted device provided with the above-mentioned electrodes for measuring brain activity can hold the electrodes on the head, especially with a dry electrode that does not use paste or gel, so that the electrodes can be brought into contact with the scalp. It will be easy. In particular, it is preferable to attach it via an electrode fixing portion.
Here, the "head mounting device" is a head cap having a hole at the electrode position, a headset for mounting the electrode on the head, and the like.
Further, as a 25th means, an amplification device for amplifying a brain activity signal is fixed to the brain activity measurement electrode.
By immediately amplifying the electroencephalogram measured by this with an amplification device, the influence of radio waves and magnetic fields from the outside is reduced, so that it is possible to acquire a high-quality electroencephalogram with less external noise.
Further, as the 26th means, the amplification device was fixed to the base side, and the brain activity measurement electrode was supported by the catch portion of the amplification device.
As a result, the amplification device can be attached in advance as a member on the base side, and the electrode for measuring brain activity can be attached to such an amplification device. Therefore, only the electrode for measuring brain activity can be attached to the base side independently. Improves sex.
Further, as a 27th means, the electrode for measuring brain activity is made detachable from the catch portion of the amplification device.
As a result, the work of fixing the electrodes for measuring brain activity to the base side can be easily performed.
Further, as the 28th means, the base is provided by an electrode fixing portion provided on the support portion that supports the tip portion and a base holding portion for mounting the head formed on the support portion that supports the tip portion. I tried to sandwich it.
As a result, the electrodes for measuring brain activity are firmly fixed at a predetermined position with respect to the base. It is possible to measure the brain activity of a subject simply by wearing a head-mounted device provided with electrodes for measuring brain activity that are firmly fixed in this way.
In addition, as a 29th means, the electrode for measuring brain activity is elastically supported in the direction of the scalp when the subject is worn against the base so as to be able to move forward and backward.
As a result, the electrodes can easily follow the shape of the head of the subject and come into contact with the electrodes.
Further, as a thirtieth means, the base is sandwiched between an electrode fixing plate attached to a support portion that supports the tip portion and an amplification device that amplifies a brain activity signal on the brain activity measurement electrode. I made it.
As a result, the electrodes for measuring brain activity are firmly fixed at a predetermined position with respect to the base. It is possible to measure the brain activity of a subject simply by wearing a head-mounted device provided with electrodes for measuring brain activity that are firmly fixed in this way. Further, since the electrode fixing plate is formed separately from the electrode, the shape of the electrode is not complicated and is advantageous in resin molding.

Further, as the 31st means, the brain activity is measured based on the brain activity signal obtained by the brain activity measuring electrode of any of the 1st to 23rd means.
By doing so, it is possible to reduce the time and effort required to attach the electrodes to the subject, and it is possible to provide a brain activity measurement system in which the measurement preparation time is shortened.
Further, as the 32nd means, the brain activity is measured based on the brain activity signal obtained by the head wearing device of any of the 24th to 30th means.
By doing so, it is possible to reduce the time and effort required to attach the head wearing device to the subject, and it is possible to provide a brain activity measurement system in which the measurement preparation time is shortened.
The inventions of the first to 32nd means described above can be arbitrarily combined. In particular, it is preferable to include the configuration of the first means and to include at least one configuration and combination of each invention of the second to 32nd means. Any component of each invention of the first to 32nd means may be extracted and combined with other components.

In the above invention, in the measurement of brain activity, even if the scalp grounding portion of the electrode is made of synthetic resin, electrical information as brain activity can be obtained in a measurable manner.

The schematic explanatory view of the state which uses the brain activity measurement system in 1st Embodiment. (A) is a front view and (b) is a perspective view of the electrodes used in the first embodiment. FIG. 5 is a partially enlarged explanatory view of a state in which an electrode is attached to a cap body in the first embodiment. The block diagram explaining the electrical structure of 1st Embodiment. (A) is a partially enlarged explanatory view of a state in which the electrode is attached to the cap body in the second embodiment, and (b) is a bottom view of the electrode. (A) is a perspective view of the electrode according to the third embodiment, and (b) is a front view of the electrode. (A) is a front view of the electrode according to the fourth embodiment, and (b) is a bottom view of the electrode. (A) is a front view of the electrode according to the fifth embodiment, and (b) is a perspective view of the electrode. (A) is a front view of the electrode according to the sixth embodiment, and (b) is a perspective view of the electrode. (A) is a front view of the electrode according to the seventh embodiment, and (b) is a bottom view of the electrode. The front view of the electrode used in 8th Embodiment. FIG. 8 is a partially enlarged explanatory view of a state in which an electrode is attached to a cap body in the eighth embodiment. The schematic explanatory view of the state which uses the brain activity measurement system in 8th Embodiment. Top view of the electrodes in other embodiments. The explanatory view explaining the state which attaches the disk and the preamplifier to the electrode used in 9th Embodiment. FIG. 5 is a perspective view of a state in which a disk and a preamplifier are attached to the electrodes used in the ninth embodiment. 9 is a cross-sectional view of a state in which electrodes are attached to a cap body via a disk and a preamplifier in the ninth embodiment. The preamplifier (a) used in the ninth embodiment is a plan view (b) and a perspective view. The vertical sectional view of the electrode used in the tenth embodiment. In the eleventh embodiment, the drawings for explaining the electrode molding process, (a) is an explanatory view in which the layer structure when the base portion (first molded product) is molded is disassembled and explained, and (b) is an explanatory view. A front view of the second molded product in a molded state, (c) is a plan view of the second molded product. (A) is a front view of the electrode in the twelfth embodiment, and (b) is a vertical sectional view. (A) is an explanatory view explaining the layer structure of the electrode in the thirteenth embodiment in an exploded manner, and (b) is a vertical sectional view. (A) is an explanatory diagram for explaining a state before mounting the electrode on the preamplifier arranged on the cap body in the fourteenth embodiment, and (b) is an explanatory diagram for explaining a state after mounting as well. A perspective view (b) of the preamplifier used in the fourteenth embodiment is a front view. Explanatory drawing which shows the electrode and a part of the electrode in an enlarged view in another embodiment. (A) is a perspective view, (b) is a bottom view, and (c) is a front view of the electrodes used in the fifteenth embodiment. An explanatory view illustrating a state in which a disk and a preamplifier are attached to the electrodes used in the fifteenth embodiment. An explanatory view illustrating a state in which a disk and a preamplifier are attached to the electrodes used in the fifteenth embodiment. It is a figure explaining the molding process of an electrode in the fifteenth embodiment, (a) is the explanatory view which explained by disassembling the layer structure at the time of molding the base part (the first molded article), (b) is A front view of the second molded product in a molded state, (c) is a vertical sectional view of the second molded product. (A) is a perspective view and (b) is a front view of the electrodes used in the sixteenth embodiment. The perspective view of the electrode used in the 17th Embodiment. The front view of the electrode used in the 17th Embodiment. The explanatory view explaining the state which attaches the disk and the preamplifier to the electrode used in the 17th Embodiment.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.
(First Embodiment)
As shown in FIG. 1, the electroencephalogram measurement system as the brain activity measurement system of the first embodiment of the present invention includes a head cap set 1 as a head wearing device and a differential amplifier 2 as a first amplification device. And the computer 3. The head cap set 1 is provided with a cap body 4 as a hemispherical base made of elastic thick cloth, and the measurer decides to measure the brain potential (voltage) reflecting the brain waves on the cap body 4. Wear it on the subject's head so that it is oriented in the correct direction. A large number of electrodes 5 for measuring brain potential (voltage) are attached to the cap body 4 (since FIG. 1 schematically shows an electroencephalogram measurement system, only some of the electrodes 5 are displayed). ..
As shown in FIGS. 2 and 3, the electrode 5 of the first embodiment is configured in an appearance form in which three perfect circular disks are arranged in parallel with a predetermined interval on a coaxial line by a cylinder. There is. The electrode 5 is formed by gold-plating a member of an integrally molded product obtained by carving out brass. A first disk 7 as an electrode fixing portion is formed at an end portion (upper side in FIG. 2A) on the base side of a column 6 having a circular cross section as a support portion constituting the electrode 5. In the present embodiment, the diameter of the support column 6 is 1.5 mm, and the diameter of the first disk 7 is 10.0 mm. A second disk 8 as an intermediate portion is formed at a position adjacent to the first disk 7. A third disc 9 as a tip is formed at the tip end of the support column 6 at intervals from the second disc 8. The lower surface of the third disk 9 is a curved surface portion 9a as a scalp grounding portion having a spherical crown-shaped (shallow dome-shaped) outer surface. The curved surface portion 9a is a contact surface (ground contact surface) with the scalp.
In the electrode 5 having such a configuration, the space defined by the upper side of the rear surface 9b of the third disk 9, the front surface 8a of the second disk 8, and the entire circumference of the support column 6 is the third disk 9. Is designated as a storage area S1 in which the hair around the contact position is housed (escapes) when the hair is brought into contact with the scalp.
In the present embodiment, the diameter of the second disk 8 is 15.0 mm, and the diameter of the third disk 9 is 5.0 mm. The thickness of each disk 7 to 9 is 1.0 mm. The distance (length) between the first disk 7 and the second disk 8 is 2.0 mm, and the distance (length) between the second disk 8 and the third disk 9 is 10.0 mm. Has been done.

As shown in FIG. 3, the electrode 5 is detachably mounted at the position of the mounting hole 10 formed in the cap body 4. The electrode 5 is fixed by sandwiching the fabric around the mounting hole 10 of the cap body 4 between the first disk 7 arranged on the outside of the cap body 4 and the second disk 8 arranged on the inside. There is. In the first embodiment, the electrode 5 is attached from the inside of the cap body 4. The mounting hole 10 is expanded by utilizing the elasticity of the material, and the first disk 7 configured to be slightly larger than the mounting hole 10 is passed from the inside to the outside of the cap body 4 with respect to the mounting hole 10. .. Since the second disk 8 has a larger diameter than the first disk 7, it does not come out from the mounting hole 10. As a result, the fabric of the cap body 4 around the mounting hole 10 is sandwiched between the first disk 7 and the second disk 8, and the electrode 5 is fixed to the cap body 4. In such a fixed state, the first disk 7 is arranged outside the cap body 4, and the columns 6 and the third disk 9 below the second disk 8 are arranged inside the cap body 4. Will be done. A preamplifier 11 as a second amplification device is arranged on the upper surface of the first disk 7. The preamplifier 11 is fixed by the conductive double-sided tape 12. The preamplifier 11 amplifies the voltage acquired by the electrode 5. The preamplifier 11 of each electrode 5 is connected to the differential amplifier 2 via the cable 13, and the differential amplifier 2 is connected to the computer 3 via the cable 14.

Next, the electrical configuration of the electroencephalogram measurement system used in the first embodiment will be described with reference to FIG.
Each of the electrodes 5 is connected to an interface 20 arranged in the differential amplifier 2 via a preamplifier 11 and a differential amplifier 2, and potential data (voltage data) is generated as brain waves acquired by the computer 3 via the interface 20. It is output.
The preamplifier 11 is attached to each electrode 5 and amplifies the acquired electroencephalogram voltage at that position. The differential amplifier 2 includes a differential amplifier circuit, and calculates and amplifies an electroencephalogram voltage and a potential difference obtained from a reference electrode (not shown). Further, the differential amplifier 2 has a function of reducing noise by a built-in filter circuit. The potential data amplified by the differential amplifier 2 is output to the computer 3 as detection target data via the cable 14.
The computer 3 is composed of a CPU (central processing unit) 21, a storage device 22, and peripheral devices thereof. The CPU 21 performs arithmetic processing based on a program stored in the storage device. The storage device 22 stores basic programs such as a program for controlling the operation of the CPU 21 and an OA processing program (for example, a Japanese input function, a printing function, etc.) that manages functions that can be applied in common to a plurality of programs. ing. Further, a program for capturing potential data, a program for calculating the potential difference, a program for estimating the current direction, a program for calculating the reliability of measurement data, and the like are stored. An input device 23 (mouse, keyboard, etc.) and a monitor 24 are connected to the CPU 21. The monitor 24 can display the measurement results such as the obtained brain waves and differences.

With the above configuration, the following effects are obtained in the first embodiment.
(1) Since the head cap set 1 is made of a thick cloth on the cap body 4, it has a sufficient weight. Therefore, the electrode 5 comes into contact with the scalp and the electroencephalogram potential can be measured just by wearing the head cap set 1. Therefore, unlike a wet electrode, it is not necessary to use a paste or the like to hold the electrode, and a simple and easy-to-use electroencephalogram measurement system can be provided.
(2) When measuring the brain waves of a subject who has a lot of hair with a normal dry electrode, the hair around the electrode is likely to be pinched, or the electrode is often separated from the scalp by shifting the electrode. However, in the first embodiment, the electrode 5 abuts the electrode 5 on the scalp because the third disk 9 that abuts on the scalp extends in the width direction and the accommodating area S1 is formed behind the third disk 9. The hair around the electrode 5 can be escaped to the accommodating area S1 at the time of making the electrode 5, and even if the electrode 5 is brought into contact with the scalp or the electrode 5 is slightly displaced after the contact, the third circle The problem that the curved surface portion 9a of the plate 9 does not come into contact with the scalp is unlikely to occur.
(3) The electrode 5 has a cap holding portion composed of a first disk 7 and a second disk 8, and the cap body 4 is firmly held by the first and second disks 7 and 8. In addition, the cap body 4 can be supported and held in a floating state by the second disk 8 from below. Therefore, the cloth of the cap body 4 does not press the hair, and the function of releasing the hair can be maintained, so that poor contact of the electrode with the dry electrode is less likely to occur.
(4) Since the entire contact surface of the curved surface portion 9a of the third disk 9 that comes into contact with the scalp is formed of a curved surface, even if the electrode 5 is slightly tilted and comes into contact with the scalp, the scalp is always at a "point". It will come into contact with the hair, making it difficult to pinch the hair.
(5) Unlike the following embodiments, since there is no clear protrusion, the subject does not have a fear of the protrusion, and the measurement can be started in a resting state.

(Second Embodiment)
The second embodiment is a variation of the electrode 5 of the first embodiment. Therefore, detailed description of the configuration common to the first embodiment will be omitted, and the points different from the electrode 5 of the first embodiment will be mainly described. In the drawings, the members common to the electrode 5 of the first embodiment are given common numbers and the description thereof will be omitted.
As shown in FIGS. 5A and 5B, the electrode 25 of the second embodiment has three round discs formed on the same coaxial line by a cylinder as in the case of the electrode 5 of the first embodiment. It is configured in an appearance form in which the electrodes are arranged in parallel with each other at predetermined intervals. The electrode 5 is formed by gold-plating a member of an integrally molded product obtained by carving out brass. The electrode 25 of the second embodiment includes a third disk 26 having a tip portion larger than the third disk 26 of the electrode 5 of the first embodiment. The diameter of the third disk 26 is 15.0 mm and the thickness is 1.0 mm. The strut 27 of the second embodiment has the same length as the strut 6 of the first embodiment, and only its diameter has a large diameter (3.0 mm). A plurality of contact pins 28 (five as an example in the second embodiment) as a columnar scalp grounding portion are integrally formed on the front surface 26a formed on the plane of the third disk 26. .. Each contact pin 28 is configured to have the same shape, and in the second embodiment, both the height and the diameter are configured to be 1.5 mm. As shown in FIG. 5B, each contact pin 28 is located slightly inward from the peripheral edge of the third disk 26 with the position 5 mm outward from the center of the third disk 26 as the axial center position. Are evenly spaced along the perimeter.
In the electrode 25 having such a configuration, the space defined by the upper side of the rear surface 26b of the third disk 26, the front surface 8a of the second disk 8, and the entire circumference of the support column 27 is the third disk 26. When the contact pin 28 of the above is brought into contact with the scalp, the accommodation area S2 in which the hair around the contact position is accommodated (escapes) is defined.

With the above configuration, in the second embodiment, the following effects are obtained in addition to the same effects as in (1) to (3) of the first embodiment.
(1) Since the third disk 26 is formed to be wide, it is stable, and when the electrode 25 comes into contact with the scalp, it does not wobble easily, so that the contact pin 28 firmly touches the scalp.
(2) By providing the contact pin 28, the electrode can be brought into contact with the scalp even for a subject having a lot of hair. Then, even when the hair is sandwiched between the tip of the contact pin 28 and the scalp, the hair sandwiched between the electrode and the scalp can be released to the accommodation area S2 by shifting (moving) the electrode on the spot. Therefore, even a slight protrusion of the contact pin 28 can be brought into contact with the scalp.
(3) Since a plurality of contact pins 28 are arranged in a well-balanced manner, even if the electrodes 25 are slightly displaced or floated, one of the contact pins 28 will always be in contact with the scalp, and poor contact of the electrodes is unlikely to occur. .. In addition, since there are a plurality of numbers (five in this case), the pressure is dispersed and the contact pins 28 do not bite into the scalp and the subject does not feel pain.
(4) Since the third disk 26 is formed to be wide, the accommodating area S2 becomes large, and a large amount of hair can be accommodated.
(5) Since the length of the contact pin 28 is very short, it is possible to suppress the fear of the protrusions from the subject and start the measurement in a resting state.

(Third Embodiment)
The third embodiment is a variation of the electrode 25 of the second embodiment. Therefore, detailed description of the configuration common to the first and second embodiments will be omitted, and the points different from the electrode 25 of the second embodiment will be mainly described. In the drawings, the members common to the electrodes 25 of the second embodiment are designated by common numbers and the description thereof will be omitted.
As shown in FIGS. 6A and 6B, the electrode 31 of the third embodiment has three round discs formed on the same coaxial line by a cylinder as in the case of the electrode 25 of the second embodiment. It has a basic appearance form in which it is arranged in parallel with a predetermined interval. The electrode 31 is formed by gold-plating a member of an integrally molded product obtained by carving out brass as in each of the above-described embodiments.
The electrode 31 of the third embodiment includes a third disk 32 having the same size as the electrode 25 of the second embodiment as a tip end portion. Five contact pins 33 as a columnar scalp grounding portion are integrally formed on the front surface 32a formed on the flat surface of the third disk 32. Each contact pin 33 is configured to have the same shape, and in the third embodiment, it is configured to have a height of 3.0 mm and a diameter of 1.5 mm. The abutting pin 33 is arranged along the peripheral edge at a position slightly inward from the peripheral edge of the third disk 32 with the position 5 mm outward from the center of the third disk 32 as the axial center position. Has been done. On the rear surface 32b formed on the plane of the third disk 32, a plurality of plate-shaped return portions (six as an example in the third embodiment) having a substantially rectangular parallelepiped shape having a slightly arched cross section. 34 is integrally formed. Each return portion 34 is configured to have the same shape, and in the third embodiment, the height is 3.0 mm and the outermost width is 2.0 mm. As shown in FIG. 6A, each return portion 34 is arranged along the outer periphery of the third disk 32 at equal intervals along the outer periphery.
In the electrode 31 having such a configuration, the space defined by the upper side of the rear surface 32b of the third disk 32, the front surface 8a of the second disk 8 and the entire circumference of the support column 27 is the third disk 32. When the contact pin 33 of the above is brought into contact with the scalp, the accommodation area S3 in which the hair around the contact position is accommodated (escape) is defined.

By configuring as described above, the third embodiment is similar to (1) to (3) of the first embodiment and (1) to (5) of the second embodiment. In addition to the effect, the following effects are produced.
(1) Since the return portion 34 is provided behind the third disk 32, the hair once accommodated in the accommodation area S3 is caught by the return portion 34 and is less likely to fall out of the accommodation area S3. Therefore, the hair once released to the accommodation area S3 does not come out, and the electrode 31 is more easily brought into contact with the scalp.
(2) Since the return portion 34 is configured to have an arch-shaped cross section (or a fan-shaped cross section) so as to be convex outward, the surrounding hair is guided by a curved surface facing the outer surface side and enters the accommodation area S3. On the contrary, once it enters, it interferes with the inner corner of the return portion 34 from the accommodating area S3 and is difficult to fall off. Further, since the area of the portion with the return portion 34 is smaller than the portion without the return portion 34 on the entire circumference of the third disk 32, the entry of the approaching hair into the accommodation area S3 is not hindered as much as possible.

(Fourth Embodiment)
The fourth embodiment is a variation of the electrode 25 of the second embodiment. Therefore, detailed description of the configuration common to the first and second embodiments will be omitted, and the points different from the electrode 25 of the second embodiment will be mainly described. In the drawings, the members common to the electrodes 25 of the second embodiment are designated by common numbers and the description thereof will be omitted.
As shown in FIGS. 7A and 7B, the electrode 36 of the fourth embodiment is different from the electrodes 25 and 31 of each of the above embodiments, and only the third disk 37 is not a perfect circle but a length. It is configured in an elliptical shape. That is, the shape is different from that of the second disk 8. The electrode 36 is formed by gold-plating a member of an integrally molded product obtained by carving out brass as in each of the above-described embodiments. In the fourth embodiment, the third disk 37 has a major axis of 15.0 mm, a minor axis of 5.5 mm, and a thickness of 1.0 mm. Three contact pins 38 as a columnar scalp grounding portion are integrally formed on the front surface 37a formed on the flat surface of the third disk 37. The three contact pins 38 are arranged in series along the major axis direction of the oblong third disk 37 at equal intervals. Each contact pin 38 has the same shape, and in the third embodiment, it has a height of 2.0 mm and a diameter of 3.0 mm.
In the electrode 36 having such a configuration, the space defined by the upper side of the rear surface 37b of the third disk 37, the front surface 8a of the second disk 8, and the entire circumference of the support column 27 is the third disk 37. When the contact pin 28 of the above is brought into contact with the scalp, the accommodation area S4 in which the hair around the contact position is accommodated (escapes) is defined.
By configuring as described above, the fourth embodiment is similar to (1) to (3) of the first embodiment and (1) to (5) of the second embodiment. In addition to the effect, the following effects are produced.
(1) Since the third disk 37, which is the contact portion with the scalp, has an elliptical shape, the electrodes can be installed according to the direction of the subject's hair, so that the electrodes are brought into contact with the scalp. It can be done easily.

(Fifth Embodiment)
The fifth embodiment is a variation of the electrode 31 of the third embodiment. Therefore, detailed description of the configuration common to the first to third embodiments will be omitted, and the points different from the electrode 31 of the third embodiment will be mainly described. In the drawings, the members common to the electrodes 25 of the second embodiment are designated by common numbers and the description thereof will be omitted.
As shown in FIGS. 8 (a) and 8 (b), the electrode 41 of the fifth embodiment is formed by forming three perfect circular disks on the coaxial line by a cylinder, similarly to the electrode 31 of the third embodiment. It has a basic appearance form in which it is arranged in parallel with a predetermined interval. The electrode 41 is formed by gold-plating a member of an integrally molded product obtained by carving out brass as in each of the above-described embodiments.
The electrode 41 of the fifth embodiment includes a third disk 42 having the same size as the electrode 25 of the third embodiment as a tip end portion. Five contact pins 43 as a columnar scalp grounding portion are integrally formed on the front surface 42a formed on the flat surface of the third disk 42. Each contact pin 43 has the same shape, and in the fifth embodiment, it has a height of 3.0 mm and a diameter of 1.5 mm. The abutting pin 43 is arranged along the peripheral edge at a position slightly inward from the peripheral edge of the third disk 42 with the position 5 mm outward from the center of the third disk 42 as the axial center position. Has been done. A plurality of truncated cone-shaped return portions 44 (five as an example in the fifth embodiment) are integrally formed on the rear surface 42b formed on the plane of the third disk 42. Each return portion 44 is configured to have the same shape, and in the fifth embodiment, the height is 4.0 mm, the diameter of the lower base is 3.0 mm, and the diameter of the upper base is 1.5 mm. The return portions 44 are arranged along the outer periphery of the third disk 42 at equal intervals.
In the electrode 41 having such a configuration, the space defined by the upper side of the rear surface 42b of the third disk 42, the front surface 8a of the second disk 8, and the entire circumference of the support column 27 is the third disk 42. When the contact pin 43 of the above is brought into contact with the scalp, the accommodation area S5 in which the hair around the contact position is accommodated (escapes) is defined.

By configuring as described above, the fifth embodiment is similar to (1) to (3) of the first embodiment and (1) to (5) of the second embodiment. In addition to the effect, the following effects are produced.
(1) Since the return portion 44 is provided behind the third disk 42, the hair once accommodated in the accommodation area S5 is caught by the return portion 44 and is less likely to fall out of the accommodation area S5. Therefore, the hair once released to the accommodation area S5 does not come out, and the electrode 41 is more easily brought into contact with the scalp.
(2) Since the return portion 44 is configured to have a curved surface shape that is convex outward, the surrounding hair is guided by the curved surface facing the outer surface side and easily enters the accommodation area S5.

(Sixth Embodiment)
The sixth embodiment is a variation of the electrode 31 of the third embodiment. Therefore, detailed description of the configuration common to the first to third embodiments will be omitted, and the points different from the electrode 31 of the third embodiment will be mainly described. In the drawings, the members common to the electrodes 25 of the second embodiment are designated by common numbers and the description thereof will be omitted.
As shown in FIGS. 9A and 9B, the electrode 46 of the sixth embodiment has three round discs formed on the same coaxial line by a cylinder as in the case of the electrode 31 of the third embodiment. It has a basic appearance form in which it is arranged in parallel with a predetermined interval. The electrode 46 is formed by gold-plating a member of an integrally molded product obtained by carving out brass as in each of the above-described embodiments.
The electrode 46 of the sixth embodiment includes a third disk 47 having the same size as the electrode 31 of the third embodiment as a tip end portion. Five contact pins 48 as a columnar scalp grounding portion are integrally formed on the front surface 47a formed on the flat surface of the third disk 47. Each contact pin 48 has the same shape, and in the sixth embodiment, it has a height of 3.0 mm and a diameter of 1.5 mm. The abutting pin 48 is located 5 mm outward from the center of the third disk 47 as the axial center position, and is located slightly inward from the peripheral edge of the third disk 47 along the peripheral edge at equal intervals. Have been placed.
A plurality of return portions 49 (six in the sixth embodiment as an example) having a substantially rectangular parallelepiped shape having a slightly arched cross section are integrally formed on the front surface 8a of the second disk 8. Each return portion 49 is configured to have the same shape, and in the sixth embodiment, the height is 4.0 mm and the outermost width is 2.0 mm. As shown in FIG. 9B, the return portions 49 are arranged along the outer periphery of the second disk 8 at equal intervals.
In the electrode 46 having such a configuration, the space defined by the upper side of the rear surface 47b of the third disk 47, the front surface 8a of the second disk 8, and the entire circumference of the support column 27 is the third disk 47. When the contact pin 48 of the above is brought into contact with the scalp, the accommodation area S6 in which the hair around the contact position is accommodated (escape) is defined.

By configuring as described above, the sixth embodiment is similar to (1) to (3) of the first embodiment and (1) to (5) of the second embodiment. In addition to the effect, the following effects are produced.
(1) Since the return portion 49 is provided in front of the second disk 8, the hair once accommodated in the accommodation area S3 is caught by the return portion 49 and is less likely to fall out of the accommodation area S6. Therefore, the hair once released to the accommodation area S6 does not come out, and the electrode 46 is more easily brought into contact with the scalp.
(2) Since the return portion 49 is configured to have an arch-shaped cross section (or a fan-shaped cross section) so as to be convex outward, the surrounding hair is guided by a curved surface facing the outer surface side and enters the accommodation area S6. On the contrary, once it enters, it interferes with the inner corner of the return portion 49 from the accommodating area S6 and is difficult to fall off. Further, since the area of the portion with the return portion 49 is smaller than the portion without the return portion 49 on the entire circumference of the third disk 47, the entry of the approaching hair into the accommodation area S6 is not hindered as much as possible.

(7th Embodiment)
The seventh embodiment is a variation of the electrode 25 of the second embodiment. Therefore, detailed description of the configuration common to the second embodiment will be omitted, and the points different from the electrode 25 of the second embodiment will be mainly described. In the drawings, the members common to the electrodes 25 of the second embodiment are designated by common numbers and the description thereof will be omitted.
As shown in FIGS. 10A and 10B, the electrode 51 of the seventh embodiment is formed by forming three perfect circular disks on the coaxial line by a cylinder, similarly to the electrode 25 of the third embodiment. It has a basic appearance form in which it is arranged in parallel with a predetermined interval. The electrode 51 is formed by gold-plating a member of an integrally molded product obtained by carving out brass as in each of the above-described embodiments.
The support column 52 of the electrode 51 of the seventh embodiment is formed in a circular cross section, and unlike the support column 6, the thickness is not uniform and is configured in a so-called trumpet type in which the diameter gradually increases from the upper side to the lower side. ing. The electrode 51 of the seventh embodiment includes a third disk 53 having the same size as the electrode 25 of the second embodiment as a tip end portion. The distance (length) between the second disk 8 and the third disk 53 is set to 8.0 mm. On the front surface 53a formed on the plane of the third disk 53, five contact bodies 54 as scalp grounding portions having a spherical crown-shaped (shallow dome-shaped) outer surface are integrally formed. Each abutting body 54 is configured to have the same shape, and in the seventh embodiment, the height from the front surface 53a to the apex is 1.0 mm, and the diameter at the base position is 4.0 mm. The abutting body 54 is arranged along the peripheral edge at a position slightly inward from the peripheral edge of the third disk 53 with the position 5 mm outward from the center of the third disk 53 as the axial center position. Has been done. The connecting surface between the base portion (the foot of the mountain) and the front surface 53a of each abutting body 54 is formed of a gently continuous curved surface, and there is no discontinuous step on the connecting surface.
In the electrode 51 having such a configuration, the space defined by the upper side of the rear surface 53b of the third disk 53, the front surface 8a of the second disk 8, and the entire circumference of the support column 52 is the third disk 53. When the abutting body 54 of the above is brought into contact with the scalp, the accommodation area S7 in which the hair around the abutting position is accommodated (escapes) is defined.

By configuring as described above, the seventh embodiment is similar to (1) to (3) of the first embodiment and (1) to (4) of the second embodiment. In addition to the effect, the following effects are produced.
(1) Since the abutting body 54 is a sphere, it comes into contact with the scalp at a point rather than a surface, and even if the hair is sandwiched under the third disk 53, the grounding portion of the abutting body 54 itself is the hair. Is less likely to be pinched.
(2) Since the connecting portion between the front surface 53a of the disk 53 and the abutting body 54 has a continuous surface shape, the tip portion can be easily wiped and can be easily cleaned.

(8th Embodiment)
The eighth embodiment is a variation of the electroencephalogram measurement system of the first embodiment. Therefore, detailed description of the configuration common to the first embodiment will be omitted, and the points different from the electrode 5 of the first embodiment will be mainly described. In the drawings, the members common to the first embodiment are designated by common numbers and the description thereof will be omitted.
As shown in FIG. 13, the electroencephalogram measuring system according to the eighth embodiment of the present invention includes a head cap set 61 as a head wearing device and a computer 62. The head cap set 61 includes a cap body 63 as a base made of a lightweight and rigid plastic frame. A differential amplifier 64 as a first amplifier is housed on the inner surface of the cap body 63. Similar to the first embodiment, the potential data amplified by the differential amplifier 62 is output to the computer 62 as detection target data via the cable 60. The subject wears the cap body 63 on the subject's own head so as to have a predetermined orientation for measuring the brain potential (voltage) reflecting the brain wave. A large number of electrodes 65 for measuring brain potential (voltage) are arranged on the inner surface of the cap body 63 (since FIG. 13 schematically shows an electroencephalogram measurement system, only some of the electrodes 65 are displayed. There is).

As shown in FIGS. 11 and 12, the electrode 65 of the eighth embodiment is configured to have a tower-shaped appearance in which the upper portion is narrowed and the lower portion is wide. The electrode 65 is formed by gold-plating a member of an integrally molded product obtained by carving out brass as in each of the above-described embodiments. A male screw portion 66 as a fastening portion is formed on the upper portion (base portion) of the electrode 65. An upper disk 67 as an intermediate portion is formed at a lower position adjacent to the male screw portion 66. A lower disk 69 as a tip is formed at the end of the support column 68 on the tip side at intervals from the upper disk 67. The strut 68 is formed in a circular cross section like the strut 52 of the seventh embodiment, and is configured in a so-called trumpet shape in which the diameter gradually increases from the upper side to the lower side.
On the front surface 69a formed on the flat surface of the lower disk 69, five abutting bodies 70 as scalp grounding portions having a spherical crown-shaped (shallow dome-shaped) outer surface are integrally formed. Each abutting body 70 is configured to have the same shape, and in the eighth embodiment, the height from the front surface 69a to the apex is 1.5 mm, and the diameter at the base position is 3.0 mm. The abutting body 70 is arranged along the peripheral edge at equal intervals at a position slightly inward from the peripheral edge of the lower disk 69 with a position 5 mm outward from the center of the lower disk 69 as the axial center position. The connecting surface between the base portion (the foot of the mountain) and the front surface 69a of each abutting body 70 is formed of a gently continuous curved surface, and there is no discontinuous step on the connecting surface.
The diameter of the upper disk 67 is 5.0 mm, and the diameter of the lower disk 69 is 10.0 mm. The thickness of both disks 67 and 69 is 1.0 mm. The distance (length) between the upper disk 67 and the lower disk 69 is 6.0 mm.
In the electrode 5 having such a configuration, the space defined by the upper side of the rear surface 69b of the lower disk 69, the front surface 67a of the upper disk 67, and the entire circumference of the support column 68 is the contact body 70 of the lower disk 69. It is defined as a storage area S8 in which the hair around the contact position is housed (escapes) when the hair is brought into contact with the scalp.

As shown in FIG. 12, the electrode 65 is held by the holder 71 in the cap body 63. The holder 71 is a columnar member formed by carving out brass, and a female screw portion 72 as a fastening portion for screwing the male screw portion 66 of the electrode 65 is formed at the tip thereof. The holder 71 is housed in a storage chamber 72 formed on the inner peripheral surface of the cap body 63. The holder 71 is held by a coil spring 74 with respect to the bottom 73 of the accommodation chamber 72. A preamplifier 76 as a second amplification device is arranged at the base of the holder 71 via a conductive double-sided tape 75. The preamplifier 76 of each electrode 65 is connected to the differential amplifier 64 via the cable 77, and the differential amplifier 64 is connected to the computer 62 via the cable 78. The configuration of the computer 62 is similar to that of the computer 3 of the first embodiment.

By configuring as described above, in the eighth embodiment, (1) to (3) of the first embodiment, (1) to (4) of the second embodiment, and the above-mentioned first embodiment. In addition to the same effects as in (1) and (2) of the seventh embodiment, the following effects are produced.
(1) Since the electrode 65 is held by the holder 71 and the holder 71 is held by the coil spring 74, the electrode 65 has elasticity in the accommodation chamber 72 when the subject wears the head cap set 61. You can move forward and backward. By making the electrode 65 elastic in this way, it is possible to absorb the peculiarity of the shape of the head of an individual, and the electrode can be reliably brought into contact with the scalp to measure brain waves.
(2) Since the electrode 65 is attached to the holder 71 of the cap body 63, the attachment / detachment work is easy and the position of the electrode 65 can be accurately determined.
(3) Since the conventional electrode does not have a mechanism for letting the hair escape, it is necessary for the measurer to put on the head cap set on the subject so that the electrode touches the scalp. However, since the electrode 65 includes the accommodating area S8, the electrode can be grounded to the scalp by slightly shifting the cap body 63 after the cap body 63 is attached, and the electroencephalograph can be attached by one subject.

(9th embodiment)
The ninth embodiment is a variation of the electroencephalogram measurement system of the first embodiment. Therefore, detailed description of the configuration common to the first embodiment will be omitted, and the points different from the electrode 5 of the first embodiment will be mainly described. In the drawings, the configurations common to those of the second embodiment are designated by common numbers and the description thereof will be omitted. The electrode 85 of the ninth embodiment is an integrally molded product made of synthetic resin, unlike the electrodes of each of the above-described embodiments.
The electrode 85 of the ninth embodiment is composed of a non-conductive hard thermosetting synthetic resin (for example, ABS resin). Carbon fibers, which are conductive fibers, are mixed in the synthetic resin in a dispersed manner. 30% by weight of carbon fibers having a length of about 2.0 mm is added to the synthetic resin.
As shown in FIGS. 15 and 16, the electrode 85 has a coma-shaped three-dimensional shape having a circular circumferential direction that is rotationally symmetric, and the tip portion 86 is formed to have a large diameter, and the base portion 87 that serves as a support portion (in the figure). The upper side) is formed with a relatively small diameter. The outer peripheral shape is formed to be concave outward so that the diameter gradually increases from the base portion 87 toward the tip portion 86 (that is, the hem expands). Then, the outer peripheral surface is connected to the outer peripheral shape which is convex to the outside of the tip portion 86 having a kagami mochi-shaped disk shape so as to be continuous without a step.

The surface of the tip 86 in the direction opposite to the base 87 (lower side in the figure) is the scalp grounding portion 88 having a spherical crown shape composed of a gently curved surface having the most raised center and convex outward. Has been done. The maximum diameter of the tip portion 86 is 15 mm, and the distance from the maximum diameter position to the apex of the scalp ground contact portion 88 is 3 mm.
The base 87 is composed of a plurality of regions having different diameters. From the end side of the base portion 87, the first disc portion 89, the second disc portion 90, the third disc portion 91, and the connecting portion 92 are used in this order. The first disk portion 89 and the third disk portion 91 have the same diameter (φ5 mm), and the second disk portion 90 sandwiched between them has a smaller diameter (φ4 mm) and a smaller vertical width. The diameter of the position where the diameter of the connecting portion 92 adjacent to the third disk portion 91 is the smallest is larger than the diameter of the third disk portion 91 (φ6 mm), so that the shelf portion 92a is formed on the upper surface of the connecting portion 92. To.
In the electrode 85 having such a configuration, when the concavely curved entire circumference of the connecting portion 92 adjacent to the tip portion 86 abuts the scalp grounding portion 88 on the scalp, the hair around the abutting position is accommodated. It is designated as the accommodation area S9 (to escape).

The electrode 85 having such a configuration is detachably mounted at the position of the mounting hole 10 formed in the cap body 4 as in the first embodiment. In the ninth embodiment, as shown in FIGS. 15 to 17, the electrode 85 is attached to the cap body 4 by sandwiching the cap body 4 between the disc 93 and the preamplifier 95 as an amplification device. The disk 93 is a ring-shaped non-conductive plastic plate having a through hole 94 formed in the center. The diameter of the through hole 9 is slightly larger than the diameter of the third disk portion 91 and smaller than the diameter of the shelf portion 92a. As shown in FIGS. 16 and 18 (a) and 18 (b), the preamplifier 95 has a horseshoe shape with two legs 96 or a substantially U-shape with a part of the ring opened. A terminal 98 is formed on the inner peripheral surface of the preamplifier 95. The preamplifier 95 amplifies the voltage acquired by the electrode 85. The preamplifier 95 of each electrode 85 is connected to the differential amplifier 2 via a cable 97, and the differential amplifier 2 is connected to the computer 3 via a cable 14.
When mounting the electrode 85 on the cap body 4, as shown in FIG. 15, the disk 93 is first placed on the shelf 92a as shown in (1), and then mounted from one side of the cap body 4 in this state. The base 87 side is inserted through the hole 10, and the preamplifier 95 is attached to the second disk 90 as shown in (2) with respect to the base 87 exposed on the opposite side of the cap body 4 (state of FIG. 17). .. At the time of mounting, the legs 96 of the preamplifier 95 are moved so as to be expanded outward once, the preamplifier 95 is pushed in forcibly, and the inner peripheral surface of the preamplifier 95 is arranged along the outer circumference of the second disk portion 90. Wear it so that it is done. In that state, the leg 96 of the preamplifier 95 returns to the original position. The legs 96 of the preamplifier 95 act as catches for the electrodes 85. The movement of the preamplifier 95 in the vertical direction is restricted by the upper and lower first disk portions 89 and the third disk portion 91 in the mounted state. In this way, the attachment of the electrode 85 to the cap body 4 is completed with the cap body 4 sandwiched between the preamplifier 95 and the disk 93. At the same time as the electrode 85 is attached to the cap body 4, the attachment of each electrode 85 to the preamplifier 95 is completed.

Common members are assigned common numbers and description thereof will be omitted.
With the above configuration, in the ninth embodiment, the following effects are exhibited in addition to the same effects as in (1) to (5) of the first embodiment.
(1) Since the electrode 85 is a non-conductive synthetic resin containing carbon fibers and is a material having conductivity as a whole, it is light, inexpensive, has good moldability, and is advantageous in terms of mass productivity. Further, since carbon fiber is fibrous as a conductive auxiliary material, it has a large contact area and is suitable as a material for imparting conductivity to a non-conductive synthetic resin.
(2) Since the preamplifier 95 can be attached by simply inserting it into the electrode 85 from the side, the attachment / detachment work is easy.

(10th Embodiment)
The tenth embodiment is a variation of the electroencephalogram measurement system of the ninth embodiment, and is an example in which only the electrode 85 in the ninth embodiment is different. Therefore, in the tenth embodiment, only the different electrodes 100 will be described based on FIG. Further, since the shape of the electrode 100 of the tenth embodiment is the same as that of the electrode 85 of the ninth embodiment, the members common to the electrode 8 are given common numbers and the description thereof will be omitted.
The electrode 100 is made of a non-conductive hard thermoplastic plastic (for example, polycarbonate) in the electrode 85, and unlike the ninth embodiment, the plastic contains carbon fibers which are conductive fibers, that is, conductive. The sex substance group is not mixed. Instead, the conductive coat layer 101 is formed on the entire outer surface of the electrode 100 except for the uppermost surface by the dip method. The conductive coat layer 101 is coated with PEDOT / PSS having a thickness of about 30 micrometers.
With the above configuration, in the tenth embodiment, the following effects are exhibited in addition to the same effects as in (1) to (5) of the first embodiment.
(1) Since the conductive coat layer 101 is thinly formed on the outer surface of the electrode 100, the material is non-conductive plastic but has conductivity as a whole. Therefore, the plastic material can be selected relatively freely. it can. In addition, it is light, inexpensive, has good moldability, and is advantageous in terms of mass productivity.
(2) Since the electrode 100 is made of hard plastic, the electrode 100 does not bend during use, so that the conductive coat layer 101 formed thinly on the outer surface does not easily peel off.
(3) Since the electrode 100 is made of non-conductive plastic, it has lower thermal conductivity than metal when it is grounded to the scalp, and it does not cool down, so that it is comfortable to wear.
(4) Since the electrode 100 is made of non-conductive plastic, it does not give a more dangerous impression than metal, and can reduce psychological adverse effects on non-wearers.
(5) Since the conductive coat layer 101 is thinly formed on the outer surface, the very small brain potential acquired from the brain is efficiently preamplified from the conductive coat layer 101 as compared with the case where the entire electrode is conductive. Can be transmitted to 95.

(11th Embodiment)
The eleventh embodiment is a variation of the electroencephalogram measurement system of the ninth embodiment, and only the electrode 85 of the ninth embodiment is different. Therefore, in the tenth embodiment, only the different electrodes 105 will be described. Further, since the shape of the electrode 105 of the eleventh embodiment is the same as that of the electrode 85 of the ninth embodiment, the members common to the electrode 85 are given common numbers and the description thereof will be omitted.
The electrode 105 is a molded product of synthetic resin like the electrode 85 of the ninth embodiment. Both have the same external shape. That is, the outer shape of the tip 106 of the electrode 105 is the same as that of the tip 86 of the electrode 85 of the ninth embodiment, and the outer shape of the base 107, which is also a support, is the same as that of the base 87. The electrode 105 is composed of a non-conductive soft (flexible) thermosetting synthetic resin (for example, a silicone resin). The electrode 105 is formed in two stages as follows.
(A) Molding of Base 107 Using the first molding mold, a cloth 108 woven with silver-plated fibers (hereinafter referred to as silver-plated fibers) on a conductive, for example, non-conductive base material is placed in the center. The mold is filled with the synthetic resin in a molten state together with the cloth 108 to form the first molded product 109 in which the cloth 108 is embedded, that is, the base 107.
FIG. 20A shows the first molded product 109 (base 107) in an exploded manner. The cloth 108 is embedded in a sandwich shape at the center position of the first molded product 109 so that the end face is exposed. In reality, since the synthetic resin is soaked into the gaps between the fibers of the cloth 108, it cannot be divided neatly in this way, and the cloth 108 is integrated with the synthetic resin portion.
(B) Molding of Tip 106 The first molded product 109 (base 107) is set in advance in the second mold. Then, a non-conductive soft thermosetting synthetic resin (for example, silicone resin) mixed with 5.0% by weight of silver-plated fibers having a length of about 1.0 mm is filled in the second mold. A second molded product 110 (electrode 105) integrated with the first molded product 109 is obtained (states of FIGS. 20B and 20C).
The electrode 105 thus obtained is integrated with the synthetic resin on the tip 106 side where the lower end of the cloth 108 is made conductive by the silver-plated fiber by the second stage molding. ..

By configuring as described above, the eleventh embodiment has the same effects as (1) to (5) of the first embodiment and (1) to (2) of the ninth embodiment. In addition, the following effects are produced.
(1) By embedding the cloth 108 in the electrode 105, when the subject's brain wave is acquired, the brain potential is efficiently transmitted through the cloth 108.
(2) Since the electrode 105 is made of a flexible silicone resin, it is easy to adhere to the scalp and the psychological burden on the subject is small.
(3) Using a flexible silicone resin as a material, the base portion 107 is integrally molded from the tip portion 106, and the tip portion 106 and the base portion 107 forming a mirror-shaped disc shape gradually gradually move from the base portion 87 to the tip portion 86. It is configured to have a concave shape on the outside so as to have a large diameter. Since the connections are gradually made without steps in this way, even if the tip 106 is deformed in various ways due to the use of the electrode 105, it is difficult for a crack to occur in the connection.
(4) Very small obtained from the brain by embedding cloth 108 in the electrode 105 instead of dispersing conductive fibers (silver-plated fibers) in all of the base 107 and the tip 106 of the electrode 105. Brain potential can be transmitted efficiently (ie, without deterioration).
(5) The cloth 108 (conductor) is embedded inside and does not come into contact with the scalp, and the tip portion 106 that comes into contact with the scalp is made of a material in which conductive fibers are mixed with the base material. Is good.
(6) The cloth 108 (conductor) is not worn due to the contact between the tip and the scalp by measuring the brain activity, and the decrease in conductivity due to long-term use can be prevented.

(12th Embodiment)
The twelfth embodiment is a variation of the electroencephalogram measurement system of the eleventh embodiment, and the electroencephalogram measurement system of the ninth embodiment is different only in the electrode 85 as in the eleventh embodiment. Therefore, in the twelfth embodiment, only the different electrodes 111 will be described. Further, since the shape of the electrode 111 of the twelfth embodiment is the same as that of the electrode 85 of the ninth embodiment and the electrode 105 of the eleventh embodiment, the members common to the electrodes 85 and 105 are common. Numbers are added and the description is omitted.
The electrode 111 is formed in two steps as in (A) and (B) of the eleventh embodiment. However, in the molding of (A) the base portion 107, a non-conductive hard thermosetting resin (for example, ABS resin) is used as a material, and in the molding of the (B) tip portion 106, the non-conductive A soft (flexible) thermosetting resin (eg, silicone resin) is used. For molding the tip 106, a non-conductive soft material in which a silver-plated fiber having a length of about 2.0 mm is mixed with 5.0% by weight and powdered silver powder is mixed with 5.0% by weight. It is molded from the thermosetting synthetic resin (for example, silicone resin).
In the electrode 105 of the eleventh embodiment, the conductor was cloth 108, whereas the conductor wire 112 made of copper alloy was used as shown in FIGS. 21 (a) and 21 (b). The lead wire 112 is embedded from the tip portion 106 to the base portion 107, and the base portion side extends from the upper surface of the first disk portion 89. The portion extending to the outside is wound around the outer circumference of the second disk portion 90, and the preamplifier 95 is mounted from above. The tip end side of the lead wire 112 is deeply embedded in the tip portion 106.
By configuring as described above, in the twelfth embodiment, the same effects as (1) to (5) of the first embodiment and (1) to (2) of the ninth embodiment are obtained. In addition, the following effects are produced.
(1) Since the lead wire 112 is embedded in the electrode 111, noise signals from the outside are less likely to be mixed. Further, when the subject's electroencephalogram is acquired, the electroencephalogram does not escape to the surroundings and is transmitted along the lead wire 112.
(2) Since the electrode 111 is made of a flexible silicone resin, it can be easily brought into close contact with the scalp.
(3) Very small obtained from the brain by embedding the conductive wire 112 in the electrode 107 instead of dispersing the conductive fibers (silver-plated fibers) in all of the base 107 and the tip 106 of the electrode 111. Brain potential can be transmitted efficiently (ie, without deterioration).
(4) Since the density can be increased by mixing a group of conductive substances having different morphologies such as silver-plated fiber and silver powder, a very small brain potential obtained from the brain can be efficiently (that is, deteriorated). Can tell (without letting).

(13th Embodiment)
The thirteenth embodiment is a variation of the electroencephalogram measurement system of the eleventh embodiment. Further, as in the eleventh embodiment, only the electrode 85 is different in the electroencephalogram measurement system of the ninth embodiment. Therefore, in the thirteenth embodiment, only the different electrodes 115 will be described. Further, since the shape of the electrode 115 of the thirteenth embodiment is the same as that of the electrode 85 of the ninth embodiment and the electrode 105 of the eleventh embodiment, the members common to the electrodes 85 and 105 are common. Numbers are added and the description is omitted.
The electrode 115 of the thirteenth embodiment is composed of a non-conductive soft (flexible) thermosetting synthetic resin (for example, a silicone resin) like the electrode 105 of the eleventh embodiment. However, unlike the electrode 105, the electrode 115 is not molded in two steps, but is molded in one step as follows.
As shown in FIGS. 22 (a) and 22 (b), a first molding die was used, a conductive cloth 116 in which nylon was coated with PEDOT / PSS was placed in the center, and the melted state was synthesized together with the cloth 116. The resin is filled in the mold to form the electrode 115 in which the cloth 116 is embedded.
By configuring as described above, the thirteenth embodiment has the same effects as (1) to (5) of the first embodiment and (1) to (2) of the ninth embodiment. In addition, the following effects are produced.
(1) Since the cloth 116 is embedded in the electrode 115, when the subject's brain wave is acquired, the brain potential does not escape to the surroundings and is transmitted through the cloth 116.
(2) Since the electrode 115 is made of a flexible silicone resin, it easily adheres to the scalp. Since the end portion of the cloth 116 is also exposed to the scalp ground contact portion 88 and the exposed position is the apex portion, the brain potential can be reliably acquired.
(3) Since the electrode 115 can acquire brain waves only with the cloth 116, a non-conductive soft synthetic resin material can be freely selected. Further, by using a non-conductive soft synthetic resin as an auxiliary shape, the shape of the electrode can be made more stable than that of the cloth 116 alone.

(14th Embodiment)
The fourteenth embodiment is a variation of the electroencephalogram measurement system of the eighth embodiment. However, in the thirteenth embodiment, for example, the electrode 85 of the ninth embodiment is used, but the electrodes of other embodiments 10 to 13 may be used. The fourteenth embodiment particularly describes an example in which the shapes and arrangement positions of the preamplifiers 95 of the ninth to thirteenth embodiments are different. The preamplifier 119 of the fourteenth embodiment is a variation of the preamplifier 95 of the ninth to thirteenth embodiments. The preamplifier 119 is assigned a common number for the configuration common to the preamplifier 95, and the description thereof will be omitted.
As shown in FIGS. 24A and 24B, the preamplifier 119 used in the fourteenth embodiment is angled so that the inner peripheral surface 119a faces the lower surface side. The preamplifier 119 is arranged on the inner peripheral surface 63a of the cap body 63 of the head cap set 61 shown in FIG. As shown in FIGS. 23 (a) and 23 (b), a recess 120 is formed on the inner peripheral surface 63a. The preamplifier 119 is fixed to the cap body 63 in a cantilever shape so as to cross the recess 120. In such a configuration, when the electrode 85 is brought closer to the preamplifier 119 from below as shown in FIG. 23A, the first disk portion 89 comes into contact with the inner peripheral surface 119a of the preamplifier 119. By pushing, the leg 96 of the preamplifier 119 is expanded outward, the first disk portion 89 is passed between the legs 96, and the second disk portion 90 is passed through the leg 96 as shown in FIG. 23 (b). Try to pinch (catch) it. This eliminates the need for a disk 93 for the electrode 85, and allows the electrode 85 to be attached to and detached from the preamplifier 119 with a single touch.

(Fifteenth Embodiment)
The fifteenth embodiment is a variation of the electroencephalogram measurement system of the ninth embodiment, and only the electrode 85 of the ninth embodiment is different. Therefore, in the fifteenth embodiment, only the different electrodes 121 will be described.
The electrode 121 is a molded product of synthetic resin like the electrode 85 of the ninth embodiment. The fifteenth embodiment is composed of a non-conductive soft (flexible) thermosetting synthetic resin (for example, a silicone resin) as in the eleventh embodiment.
The electrode 121 is roughly divided into a base portion 122 which is a support portion arranged above and a tip portion 123 arranged below the base portion 122. Since the base portion 122 has an appearance form in which columns having different diameters that are rotationally symmetric are combined and has the same configuration as the electrode 85 of the ninth embodiment, the base portion 122 is common to the electrode 85 in FIGS. 26 to 29. A common number is assigned to the configuration to be used, and the description thereof will be omitted.

The tip portion 123 is provided with an overhanging portion 125 projecting to the outer periphery having a diameter larger than that of the third disk portion 91 at the boundary portion with the base portion 122. At the lower position of the overhanging portion 125, a scalp grounding portion 127 having a curved outer surface that looks like an almond grain cut at the center in the longitudinal direction and protrudes toward the tip is formed. As shown in FIG. 26B, the scalp grounding portion 127 is a solid having an elliptical shape in a plan view in which two orthogonal directions are the longest side and the shortest side. The scalp ground contact portion 127 has a diameter smaller than the outer diameter of the overhanging portion 125 even at the shortest side in the direction of the shortest side with respect to the overhanging portion 125, and is outside the overhanging portion 125 at the farthest side in the longest side. The diameter is larger than the diameter. The scalp grounding portion 127 is integrated with the overhanging portion 125 on the upper side to form a shelf portion 125a.
The electrode 121 is formed in two stages as follows.
(A) Molding of Base 122 Using the first molding mold, a cloth 130 woven with a conductive example of silver-plated fiber is placed in the center, and a molten synthetic resin is filled in the mold together with the cloth 130. Then, the first molded product 128 in which the cloth 130 is embedded, that is, the base 122 is molded.
FIG. 29A shows the first molded product 128 (base 122) in an exploded manner. The cloth 130 is embedded in a sandwich shape at the center position of the first molded product 128 so that the end face is exposed. Further, the cloth 130 extends below the base 122. In reality, since the synthetic resin is soaked into the gaps between the fibers of the cloth 130, it cannot be divided neatly in this way, and the cloth 130 is integrated with the synthetic resin portion.
(B) Molding of Tip 123 The first molded product 128 (base 122) is set in advance in the second mold. Then, a non-conductive soft thermosetting synthetic resin (for example, silicone resin) mixed with 5.0% by weight of silver-plated fibers having a length of about 1.0 mm is filled in the second mold. A second molded product 129 (electrode 121) integrated with the first molded product 128 is obtained (states of FIGS. 29 (b) and 29 (c)).
The electrode 121 thus obtained is integrated with the synthetic resin on the tip portion 123 side in which the lower portion of the cloth 130 is made conductive by the silver-plated fiber by the second step molding. ..

When the electrode 121 configured in this way is mounted on the cap body 4, the disk 93 is placed on the shelf 125a on the lower side of the cap body 4 as shown in FIG. 27, and the cap body is in this state. The base 122 side is inserted through the mounting hole 10 from one side of 4, and the preamplifier 95 is mounted on the second disk 90 as shown by an arrow on the base 122 exposed on the opposite side of the cap body 4 (FIG. 28). State). Since the mounting work of the preamplifier 95 is the same as that of the ninth embodiment, the description thereof will be omitted.

By configuring as described above, in the fifteenth embodiment, (1), (4), (5) of the first embodiment and (1) to (2) of the ninth embodiment In addition to the same effect as above, the following effects are produced.
(1) By embedding the cloth 130 (conductor) in the electrode 121, when the subject's electroencephalogram is acquired, the brain potential is efficiently transmitted through the cloth 108.
(2) Since the electrode 121 is made of a flexible silicone resin, it is easy to adhere to the scalp and the psychological burden on the subject is small.
(3) Since the shape of the tip portion 123 is a half-split shape of almond grains, the thickness is thinner than that of the dome shape, so that it is easy to scrape the hair and bring it into contact with the scalp.
(4) Obtained from the brain by embedding cloth 130 (conductor) in the electrode 121 instead of dispersing conductive fibers (silver-plated fibers) in all of the base 122 and the tip 123 of the electrode 121. Very small brain potential can be transmitted efficiently (ie, without deterioration).
(5) The cloth 130 (conductor) is embedded inside and does not come into contact with the scalp, and the tip portion 123 that comes into contact with the scalp is made of a material in which conductive fibers are mixed with the base material, so that the part that comes into contact with the scalp is easy to maintain. Is good.
(6) The cloth 130 (conductor) is not worn due to the contact between the tip and the scalp by measuring the brain activity, and the decrease in conductivity due to long-term use can be prevented.

(16th Embodiment)
The sixteenth embodiment is a variation of the electroencephalogram measurement system of the ninth embodiment, and only the electrode 85 of the ninth embodiment is different. It is also a variation of the fifteenth embodiment. Therefore, only the points different from the electrode 121 of the fifteenth embodiment will be described in the sixteenth embodiment.
The electrode 131 of the 16th embodiment differs from the electrode 121 of the 15th embodiment only in the tip portion 132. The base 122 is assigned a number common to that of the electrode 121 of the fifteenth embodiment, and the description thereof will be omitted. The electrode 131 is roughly divided into a base portion 122 arranged above and a tip portion 132 arranged below the base portion 122. The tip portion 132 is composed of a conical scalp ground contact portion 133 and an overhanging portion 135. The scalp grounding portion 133 has a so-called rounded shape in which the vicinity of the quadratic curved apex where the outer shape of the cross section passing through the apex without sharpening the tip (lower end) side is convex upward is cut out. The upper surface of the overhanging portion 134 is a shelf portion 134a that holds the disk 93. Like the electrode 121, the electrode 131 is also formed in two stages.
By configuring as described above, in the sixteenth embodiment, (1), (4), (5) of the first embodiment and (1) to (2) of the ninth embodiment In addition to the same effects as in (1), (2), (4) to (6) of the fifteenth embodiment, the following effects are produced. That is,
Since the shape of the tip portion 132 is conical, the thickness of the tip portion 132 near the tip is thinner than that in the case of a dome shape, so that it is easy to penetrate deep into the hair.

(17th Embodiment)
The seventeenth embodiment is a variation of the electroencephalogram measurement system of the ninth embodiment, and only the electrode 85 of the ninth embodiment is different. Therefore, in the seventeenth embodiment, only the different electrodes 135 will be described.
The electrode 135 is roughly divided into a base portion 136 which is a support portion arranged above and a tip portion 137 formed below the base portion 136. Since the base 136 has an external shape in which cylinders having different diameters that are rotationally symmetric are combined and has the same configuration as the electrode 85 of the ninth embodiment, the base 136 is common to the electrode 85 in FIGS. 31 to 33. A common number is assigned to the configuration to be used, and the description thereof will be omitted.
The tip portion 137 is composed of a disc-shaped tip portion main body 138 and a plurality of protrusions (six in the present embodiment) 139 as scalp grounding portions. The tip body 138 is a disk body having the same center position as the first to third disk portions 89, 90, 91, and has a larger diameter than the third disc portion 91. Each protrusion 139 is a leg member having a cylindrical shape with a hemispherical tip (lower end), and all have the same shape. The protrusions 139 are arranged at equal intervals on a predetermined circumference equidistant from the center of the tip body 138.

The electrode 135 is formed in two steps as in (A) and (B) of the eleventh embodiment.
(A) Processing of metal parts A metal body of an integrally molded product is formed by cutting out a portion consisting of a base portion 136, a tip portion main body 138 of the tip portion 137, and a rod-shaped portion 140 protruding from the back surface of the tip portion main body 138 with brass. Form. Gold plating is applied to this carved metal body.
(B) Molding of the protrusion 139 The plated metal body produced in (A) is set in the molding mold. Then, a non-conductive soft thermosetting synthetic resin (for example, a silicone resin) in which a silver-plated fiber having a length of about 1.0 mm is mixed in a weight ratio of 5.0% and a silver powder in a weight ratio of 5.0% is mixed. ) Is filled in the mold to form a protruding portion 139 in which the outer periphery of the rod-shaped portion 140 is surrounded by this synthetic resin. Here, the synthetic resin (for example, silicone resin) was made to have elasticity close to that of the skin by adjusting the addition amount of the silica-based powder filler.
In the electrode 135 thus obtained, a protrusion 139 surrounding the synthetic resin, which is made conductive by the silver-plated fiber and the silver powder, is integrated around the rod-shaped portion 140.
When the electrode 135 configured in this way is mounted on the cap body 4, the disk 93 is placed on the tip portion 139 on the lower side of the cap body 4 as shown in FIG. 33, and the cap body is in this state. The base 136 side is inserted through the mounting hole 10 from one side of 4, and the preamplifier 95 is mounted on the second disk 90 as shown by an arrow on the base 136 exposed on the opposite side of the cap body 4. The electrode 135 is sandwiched and held by the preamplifier 95 and the tip body 138 with respect to the cap body 4.

By configuring as described above, in the seventeenth embodiment, in addition to the same effects as (1) of the first embodiment and (1) to (2) of the ninth embodiment, the following The effect is played. That is,
(1) By providing the protrusion 139, even a subject having a lot of hair can avoid the hair and bring the electrode into contact with the scalp. Further, since the surface is curved so that the tip of the protrusion 139 is convex outward, the vicinity of the tip of the protrusion 139 surely comes into contact with the scalp.
(2) Since a plurality of protrusions 139 are arranged in a well-balanced manner, even if the electrodes 135 are slightly displaced or floated, any of the protrusions 139 will always be in contact with the scalp, and poor contact of the electrodes is unlikely to occur. In addition, since there are a plurality of numbers (6 in this case), the pressure is dispersed and the protrusions 139 do not bite into the scalp and the subject does not feel pain.
(3) Since the electrode 135 is made of a silicone resin whose protrusions have elasticity close to that of the skin, it is easy to adhere to the scalp and there is little pain due to wearing. In addition, the psychological burden on the subject is small.
(4) Since the rod-shaped portion 140 is embedded inside the protrusion 139, the protrusion 139 can be brought into contact with the scalp without bending even if the outside is a flexible silicone resin.
(5) Conductive fibers (silver-plated fibers) are not dispersed in all of the base 136 and the protrusions 139 of the electrode 135, but the base 136 is made of gold-plated brass, which is very obtained from the brain. Small brain potentials can be transmitted efficiently (ie, without degradation).
(6) Since the protrusion 139 that comes into contact with the scalp is made of a material in which conductive fibers are mixed with the base material, the maintainability of the portion that comes into contact with the scalp is good.

The invention of the present application is not limited to the above-described embodiment, and can be variously modified at the implementation stage without departing from the gist thereof. For example, it has the following aspects.
-A rough surface may be formed on the ground contact portion of the scalp at each of the electrodes 5, 25, 31, 36, 41, 46, 51, 65, 85, 100, 105, 111, 115, 121, 131, 135. For example, as shown in FIG. 25, when the electrode 125 is molded using a 3D printer, when the laminated surface is molded in the direction intersecting the scalp ground contact portion 126, a fine uneven pattern that is generally parallel is formed. It will be. By forming such a rough surface, the contact area increases when the scalp grounding portion 126 of the electrode 125 is brought into contact with the scalp, so that it becomes easier to acquire electrical information of brain waves. Further, such a rough surface may be firmly fixed to the scalp grounding portion 126 when a conductive coat layer is formed on the outer surface.
-The shapes of the electrodes 85, 100, 105, 111, 115, 121, 131, and 135 of the above embodiments 9 to 13 are examples, and may be configured by other shapes.
The synthetic resin materials of the electrodes 85, 100, 105, 111, 115, 121, 131, and 135 of the above embodiments 9 to 13 are examples, and they can be freely changed to other synthetic resin materials.
-The above electrodes 105, 111, 121, 131, and 135 are molded in two stages when they are molded by different materials, but they may be molded in three or more steps.
-In the above, the coat layer 101 is formed on the surface of a hard plastic, but it may be used on the surface of a flexible material.
-When forming the coat layer 101, a group of conductive substances such as conductive fibers, powders, and granules may be mixed with the coating agent.
-The entire electrode may be made of a plastic mixed with a group of conductive substances such as conductive fibers, powders, and granules, and cloths 108, 116, 130 and conductors 112 as conductors are embedded inside. You may do so. Further, a plastic mixed with a group of conductive substances such as fibrous, powdery, and granular may be embedded so as to be filled only at the positions of the cloths 108, 116, 130 and the conducting wire 112. That is, the electrical resistance may be increased at a portion other than the positions of the cloths 108, 116, 130 and the conducting wire 112.
The coat layer 101 may be applied to the cloth 108, 116, 130 or the electrode in which the lead wire 112 is embedded. For example, if the coat layer 101 is formed on the ground contact portion of the scalp, it becomes easier to acquire electrical information of brain waves. For example, in the twelfth embodiment and the thirteenth embodiment, the coat layer 101 may be provided on the scalp grounding portion 88 from the state of FIGS. 21 and 22.
-In the above-described embodiment, carbon fibers and silver-plated fibers are used as the conductive substance group, but other conductive substance groups may be used.
-Although the electrode 115 was formed so as to embed the cloth 116 inside in the thirteenth embodiment, the conductor 112 of the twelfth embodiment may be embedded as a conductor instead. In that case, it is preferable to expose the lead wire 112 on the outer surface of the scalp grounding portion 88 and form the coat layer 101 on the outer surface of the scalp grounding portion 88.
The coat layer 101 may be formed by means other than coating or dipping.

-The material of the electrodes 5, 25, 31, 36, 41, 46, 51, 65 in each of the above embodiments is a metal such as gold, silver, platinum, for example, as long as it is a material having good conductivity other than the above brass. Alternatively, it may be used (as plating). It may be other than metal.
-In the first to eighth embodiments, the scalp grounding portion is made of a conductive metal, but a conductive felt material may be arranged on the scalp grounding portion of the electrode. In the above, for example, a conductive felt material may be arranged on the surface of the curved surface portion 9a having a large surface area.
-In the above, when fixing the electrode 5 to the cap body 4, the mounting hole 10 is expanded to mount the first disk 7 from the inside, but this is just an example, and another method is adopted. You may.
-In the 9th to 16th embodiments described above, the resin is molded using a single resin, but for example, the base portion (support portion side) is molded with a hard resin in the first step, and the second step is formed. It is also possible to use different hard and soft resins such that only the scalp ground contact portion or only the tip portion is molded with a flexible resin.
-In each of the above embodiments, if the electrode is made of resin, the entire electrode is made of resin. However, for example, only the scalp grounding portion or only the tip portion is made of resin and a fibrous conductive substance is mixed. , The base (support side) may be made of metal.
-Since the above-mentioned fabric or plastic is an example of the material of the cap bodies 4 and 63, other materials may be used.
-In the above-mentioned return portions 34 and 44, the outer peripheral angles correspond to the outer peripheral curves of the third disks 32 and 44, respectively. However, as shown in FIG. 14, for example, an electrode which is a variation of the third embodiment. As in 81, the return portion 82 may be made to increase the curvature of the curve of the curved surface facing outward (make the curve tight). When the curvature of the curve is large in this way, the hair is more likely to be guided into the accommodation area.
-The number of return portions 34, 44 is not limited to the above.
-The fastening portion of the eighth embodiment may be configured by other means. Further, the means for giving elasticity to the electrode 65 may be an elastic means other than the coil spring 74.
The present invention is not limited to the configuration described in the above-described embodiment. The components of each of the above-described embodiments and modifications may be arbitrarily selected and combined. Further, any component of each embodiment or modification, and any component described in the means for solving the invention or a component described in the means for solving the invention are embodied. And may be configured in any combination. We also intend to acquire the rights to these in the amendment or divisional application of the present application.

5,25,31,36,41,46,51,65,85,100,105,111,115,121,131,135 ... Electrodes, 9a ... Curved part as scalp grounding part, 28,33,38, 43, 48 ... Contact pin as scalp grounding part, 54, 70 ... Contact body as scalp grounding part, 88, 126, 127, 133 ... Scalp grounding part, 139 ... Protruding part as scalp grounding part.

Claims (31)

In a brain activity measuring electrode provided with a tip having a scalp grounding portion for contacting the scalp,
The scalp ground contact portion is made of a synthetic resin material, and the synthetic resin material is spun into a shape or a fiber produced by spinning or spinning, and has a continuous length cut to an average of 1.0 mm to 3.0 mm. An electrode for measuring brain activity, which is characterized by containing a group of filamentous conductive substances having a shape of. The electrode for measuring brain activity according to claim 1, wherein the filamentous conductive substance group is contained only in the tip portion. The electrode for measuring brain activity according to claim 1 or 2, wherein a portion that does not contain the filamentous conductive substance group is provided in a portion other than the scalp grounding portion. Conductive substance group of the thread-like, brain according to any one of claims 1 to 3 in addition to the conductive substance group of the thread, characterized that you containing a conductive substance group is a finely divided form Electrode for activity measurement. The electrode for measuring brain activity according to any one of claims 1 to 4, wherein the electrode has a support portion that supports the tip portion. The electrode for measuring brain activity according to claim 5 , wherein the support portion is made of a synthetic resin material and has a portion that does not contain the filamentous conductive substance group. Brain activity measuring electrode according to claim 5 or 6 wherein the support portion is characterized Rukoto an electrode fixing unit. The electrode for measuring brain activity according to any one of claims 5 to 7, wherein the conductor is arranged from the grounded portion of the scalp to a position in the support portion region for mounting the amplification device. The electrode for measuring brain activity according to any one of claims 5 to 8, wherein the conductor is arranged from the tip portion to a position in the support portion region for mounting the amplification device. The electrode for measuring brain activity according to claim 8 or 9, wherein the conductor is a conductive layer formed on the outer surface of the tip portion and the support portion. The electrode for measuring brain activity according to claim 9 or 10, wherein the conductor is a conductive layer or a conductive wire embedded inside the tip portion and the support portion. Brain activity measuring electrode according to claim 11, characterized in that so as to contain a conductive substance group of the thread in the synthetic resin material in which the conductor is set embedded. The electrode for measuring brain activity according to any one of claims 1 to 12, wherein the scalp grounding portion is made of a flexible material. The electrode for measuring brain activity according to any one of claims 1 to 13, wherein the tip portion is made of a flexible material. The conductive substance group contained in the synthetic resin material is a mixture of the filamentous conductive substance group and the conductive substance group having at least one of powdery and granular forms. Item 4. The electrode for measuring brain activity according to any one of Items 1 to 14. The electrode for measuring brain activity according to any one of claims 1 to 15, wherein a conductive synthetic resin is used as the electrode material. The brain activity measurement according to any one of claims 5 to 16, wherein the support portion side is made of a hard material, and the tip end side is made of a material more flexible than the support portion side. Electrode for. The electrode for measuring brain activity according to any one of claims 1 to 17, wherein the conductive substance group is formed by coating the base material with a conductive material. The electrode for measuring brain activity according to any one of claims 1 to 18, wherein the outer surface of the scalp grounding portion is formed so as to be a rough surface. The electrode for measuring brain activity according to any one of claims 1 to 19, wherein the scalp grounding portion is composed of one or a plurality of protrusions. The electrode for measuring brain activity according to claim 20, wherein the protrusion has a spherical crown shape. The electrode for measuring brain activity according to any one of claims 1 to 21, wherein the grounding portion of the scalp is curved so as to be convex outward. A head-mounted device in which the brain activity measuring electrode according to any one of claims 1 to 23 is attached to a head-mounted base so that the tip thereof faces the head side when the subject is worn . The head-mounted device according to claim 23, wherein an amplification device for amplifying a brain activity signal is fixed to the brain activity measurement electrode. The head-mounted device according to claim 24, wherein the amplification device is fixed to the base side, and the brain activity measurement electrode is supported by a catch portion of the amplification device. The head-mounted device according to claim 25, wherein the brain activity measuring electrode is removable from the catch portion of the amplification device. The base is sandwiched between an electrode fixing portion provided on a support portion that supports the tip portion and a base holding portion for mounting the head formed on the support portion that supports the tip portion. 2 The head-mounted device according to any one of claims 2 to 26. The brain activity measuring electrode head mounted device according to any one of claims 2 3-27, wherein Rukoto is movably supported with elasticity in the scalp direction during subjects wearing against the base. Claim 2, wherein the support portion is mounted an electrode fixing plate, and an amplifying device for amplifying a brain activity signal to the brain activity measurement electrodes, the Rukoto not across the base by supporting the distal portion The head-mounted device according to 3. A brain activity measurement system that measures brain activity based on a brain activity signal obtained by the brain activity measurement electrode according to any one of claims 1 to 22 . A brain activity measurement system that measures brain activity based on a brain activity signal obtained by the head-mounted device according to any one of claims 23 to 29.

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