JPH056210B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a coordinate reading device used to read information such as images and input them into a computer or the like.

BACKGROUND TECHNOLOGY Recently, coordinate reading devices have been used to read image information and input it into computers, etc., but when reading using such devices, it is necessary to read the information on the original document. must be fixed to the device. Traditionally, this has been done using adhesive tape, thumbtacks, etc. however,
In such a method, a space is created between the document and the reading device, resulting in positional deviation, which tends to cause reading errors, and it is not easy to fix the document when it becomes large. Furthermore, this method has drawbacks such as it takes time to attach and remove the original, and adhesive and holes remain on the reading device after the original is removed, impairing its aesthetic appearance. In order to fix the original, there is another method: (a) A small hole is made in a part of the reading device, and this is connected to a vacuum pump to create a vacuum on the back of the original, thereby suctioning and fixing the original. (b) Magnetize the reading device and place the manuscript on it,
A method of fixing the document by placing a metal sheet on its end surface has been proposed. However, the method (a) is not practical because the equipment costs are high and noise is involved, and since the circuit is embedded in the reading plate, there is a limit to how small holes can be drilled. Further, in the method (b), a space is created between the original and the reading device, and the desired effect cannot be achieved.

On the other hand, when a dielectric layer is disposed on a group of positive and negative electrodes connected to a DC power source, and a paper or the like is brought into contact with the dielectric layer, a DC electric field is formed across the layer, and the paper or the like is electrostatically charged. It is known that the material is attracted and held by the dielectric layer due to the action. The present inventor previously devised a coordinate reading device that can attract and hold originals by applying this electrostatic force (Patent Application No. 1983-
No. 49592). In this coordinate reading device, a group of electrodes connected to a DC power source and having alternating positive and negative electrodes are printed on an electrically insulating layer using non-metallic conductive ink, and a dielectric layer is placed on the insulating layer. The apparatus is comprised of a document suction part with a document suction part placed in contact with the original suction part, and a coordinate reading part disposed below the suction part, holding a coordinate reading element, and having an insulating substrate on the bottom layer. Although this device is very useful in that it can easily and securely hold the document while reading the information contained in the document, it is somewhat thicker overall due to the large number of layers it has. , it also costs extra.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a coordinate reading device that can easily and reliably hold a document, and is thin and inexpensive as a whole.

Structure and Effects of the Invention As a result of repeated research on a coordinate reading device that can attract and hold a document using electrostatic force, the present inventor has discovered that by arranging a group of conductive wires of a specific shape on a dielectric material, The present invention was developed by focusing on the fact that a group of conductive wires functions as an electrode that exerts electrostatic attractive force and also functions as a coordinate reading element using a specific reading method. That is, the coordinate reading device of the present invention includes an electrically insulating substrate, an intermediate dielectric layer provided on the substrate, and a surface dielectric layer provided on the intermediate dielectric layer. A first group of parallel conductive lines is disposed on the substrate, and a second group of conductive lines parallel to each other and perpendicular to the first group of conductive lines is disposed on the intermediate dielectric layer. It is set up. Accordingly, at least one of the first and second conductive wire groups is connected to a DC power source and exerts an electrostatic adsorption force on the document via the intermediate dielectric layer and the surface dielectric layer. In addition, these conductive wire groups (first and second conductive wire groups) detect the position of a specific conductive wire according to the information of the document using an electromagnetic induction method or an electrostatic induction method. It is designed to be connected to a detection device.

Thus, the coordinate reading device of the present invention is thin as a whole because it is essentially composed of only three layers: the lowermost insulating substrate, the intermediate dielectric layer provided thereon, and the surface dielectric layer. Generally, 1.0~
(approximately 2.0 mm) and is easy to manufacture.

In order for the coordinate reading device of the present invention to exert electrostatic attractive force and effectively attract and hold a document placed on the surface of the device (specifically, the surface dielectric layer), it is necessary to The dielectric material constituting the body layer and the surface dielectric layer has a dielectric constant of 4 to 12, and 10 ⁸ to
Preferably, it has a volume resistivity of 10 ¹² Ω·cm. If the value of the dielectric constant is too small, the attraction force of the reading device to the document will be low, making it impractical. On the other hand, if the dielectric constant becomes too large, leakage of static electricity is likely to occur. In addition, if the resistivity of the dielectric is too large, the molecular orientation relaxation time of the dielectric will be long after the power is turned off, and the adsorbed original will not be released quickly; It will no longer be. Thus, examples of preferred materials for the dielectric layer (intermediate dielectric layer and surface dielectric layer) of the reader of the invention are hard synthetic rubber, PVF (polyvinylidene fluoride), and thermosets such as titanium melamine or phenol. These materials are generally
Used in thicknesses of 0.05-1.0mm. Note that the dielectric constant used in this specification is expressed in the MKS unit system, and is a value measured at 1 KHz at a temperature of 20° C. and 65% RH.

In the coordinate reading device of the present invention, a first conductive wire group parallel to each other is disposed on the substrate, and a second conductive wire group parallel to each other and perpendicular to the first conductive wire group is disposed on the substrate. Groups of conductive wires are arranged in the intermediate dielectric layer, and these conductive wires function both as electrodes that exert electrostatic attraction and as coordinate reading elements using electromagnetic induction and electrostatic induction methods. do. Thus, in the reading device of the present invention, the group of conductive wires is connected to a DC power source, and a detection means for reading and detecting the position (address) of a specific conductive wire according to information on the document is provided. is configured to be connected to.

In order to enable the coordinate reading device of the present invention to perform reading operations using the electromagnetic induction method, it is necessary to connect the ends of the first conductive wire group arranged on the board to either the positive or negative terminal of the DC power supply. and connect an end of a second group of conductive wires disposed in the intermediate dielectric layer to the other pole of the DC power source.
In addition, in order to enable the coordinate reading device of the present invention to perform reading operations using the electrostatic induction method, it is necessary to An end of the conductive wire is connected to one pole of the DC power source, and an end of the remaining conductive wire is connected to the other pole of the DC power source.
Similarly, for the second conductive wire group disposed in the intermediate dielectric layer, the ends of every other conductive wire are connected to the DC power source (however, the first conductive wire group is connected to Connect the end of the remaining conductive wire to the other pole of the same DC power source.

In the reading device of the present invention, the conductor disposed on the substrate and the intermediate dielectric layer includes metallic ink (for example, polyvinyl chloride mixed with silver powder) and non-metallic ink (for example, polyvinyl chloride mixed with silver powder). Although the ink may be composed of any of the following: (mixed with carbon black), metallic ink is preferable, and metallic ink is particularly preferable when the reading operation is performed using an electromagnetic induction method. The use of metallic ink has the advantage that the width of the conductive lines and the spacing between each conductive line can be reduced, allowing for precise reading operations.

An electrically insulating board is provided at the bottom of the coordinate reading device of the present invention to prevent leakage of static electricity. Examples of preferred materials for use in this insulating substrate include polyvinyl chloride sheets and epoxy resin sheets. Thus, these insulating substrates are generally used with a thickness of 0.5 to 1.5 mm.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings in order to facilitate understanding of the present invention.

FIG. 1 shows a typical example of an electromagnetic induction type coordinate reading device according to the present invention. In the figure, A is a surface dielectric layer, B is an intermediate dielectric layer, and C is an insulating substrate. As shown in the figure, the intermediate dielectric layer B has a conductive wire group D parallel to each other, and the substrate C has a conductive wire group E parallel to each other. Group E is in a positional relationship that is orthogonal to each other. The end of the conductive wire group D is connected to the negative electrode of the DC power source 1, and the end of the conductive wire group E is connected to the positive electrode of the DC power source 1. Further, the conductive wire group D is connected to a detection device 2 for detecting the address (Y coordinate position) of a specific conductive wire during a reading operation, and the conductive wire group E detects the X coordinate address of the conductive wire. It is connected to the detection device 3.

In addition, in FIG. 1 (the same applies to FIG. 2, which will be described later), each layer is shown separated for convenience, but the actual coordinate reading device is
These layers are bonded and integrated by thermocompression bonding or adhesive.

When reading coordinates using the coordinate reading device of the present invention obtained in this way, the first
As shown in the figure, when a manuscript paper 4 is placed on the top surface of the reading device and a DC voltage is applied from the power supply 1,
In each portion of the document 4 facing the conductive lines D and E through the dielectric layer A, charges having a polarity different from those of the respective conductive lines are generated. As a result, the manuscript 4
is attracted to the upper surface of the reading device by electrostatic action and is fixedly held on the reading device.

In this state, when the pen 6 to which voltage is applied from the high-frequency power supply 5 traces the image 7 on the document, the maximum current is detected through the corresponding line Yn of the conductive wires D arranged on the film B. It is detected by the device 2, and from this, the value of the Y coordinate can be known. Similarly, the value of the X coordinate can be known from the conductive wire E arranged on the film C. From both values, it is possible to determine the value of the image. Each position is sensed. All you have to do is input these values into your computer.

FIG. 2 shows a coordinate reading device that performs a reading operation by electrostatic induction according to the present invention. In the figure, A, B and C are a surface dielectric layer, an intermediate dielectric layer and an electrically insulating substrate, respectively, as in the case of FIG. However, in the reading device of FIG. 2 which uses the electrostatic induction method, as shown in the figure, among the conductive wire groups D arranged in the intermediate dielectric layer B and parallel to each other, every other conductive wire has a DC current. It is connected to one pole of the power supply 1, and the remaining conductive wires are connected to the other pole of the same DC power supply 1. Therefore, a conductive wire group E is arranged on the insulating substrate C in a positional relationship that is orthogonal to the conductive wire group D, and in this conductive wire group E, every other conductive wire is It is connected to one pole of a DC power supply 1' that is different from the DC power supply 1, and the remaining conductive wire is connected to the DC power supply 1'.
connected to the other pole of the However, this conductive wire group E may not be connected to a DC power source and may be used as a mere reading electrode.

The operation of the reading device of FIG. 2 is basically similar to the operation of the electromagnetic induction reading device shown in FIG. That is, when the original paper 4 is placed and a DC voltage is applied to the power supplies 1 and 1', a DC electric field is formed across the dielectric layer A, and the paper 4 is
is attracted and held on the dielectric layer A by electrostatic action.
As the image 7 on the document is moved in this state, the detection device detects the X-coordinate and Y-coordinate addresses (Xn, Yn) corresponding to the image. However, in the reading device shown in FIG. 2 which uses the electrostatic induction method, a tuning fork oscillator 8' is used as a pen (cursor) for tracing the image, and each address is detected by the detection devices 2' and 3'. Ru.

Next, examples of the present invention will be shown.

Example 1 An electromagnetic induction type coordinate reading device as shown in FIG. 1 was created using the following materials.

A: Thickness 0.25mm, dielectric constant 7.0, volume resistivity 3×
A sheet made of hard synthetic rubber with a resistance of 10 ¹¹ Ω・cm.

B, D: Thickness 0.25mm, dielectric constant 7.0, volume resistivity 3
×10 ¹¹ Ω・cm On sheet B made of hard synthetic rubber, conductive ink (3 × 10 ^-2 Ω・cm) obtained by mixing silver powder into polyvinyl chloride was used to ink 1 mm wide and 5 mm apart. Conductive wire group D was printed.

C, E: Conductive wires with a width of 1 mm and a spacing of 5 mm were formed on a polyvinyl chloride plate C with a thickness of 3 mm using conductive ink (3 x 10 ^-2 Ωcm) obtained by mixing silver powder into polyvinyl chloride. Group E was printed.

Layer the above together and use a thermocompression press at a temperature of 160.
℃, area pressure 25Kg/ ^cm2 , total thickness
A plate-shaped reading device with a size of 3.5 mm and a size of 400 x 450 mm was obtained.

A DC 500V is applied between B and C to attract the manuscript paper, an oscillator is placed on the suctioned manuscript paper and driven, and the image is received by the conductive wires D and E of the reading section and displayed on the display. I confirmed the gender. The adsorption force was 4.5 g/cm ² , and the image reading performance of the original was good.

Example 2 An electrostatic induction type reading device shown in FIG. 2 was created using the following materials.

A: Dielectric constant 6.3, volume resistivity 8× ¹⁰ Ω・cm, thickness
A sheet made of 0.3mm hard synthetic rubber.

B, D: dielectric constant 6.3, volume resistivity 8× ¹⁰ Ω・cm,
On sheet B made of hard synthetic rubber with a thickness of 0.3 mm, a conductive ink (5×10 ² Ω・
Conductive wire group D printed with a comb tooth shape with a width of 5 mm and an interval of 5 mm.

C, E: C on a polyvinyl chloride board with a thickness of 3 mm, D
Conductive wire group E printed in the same manner as .

Layer the above together and heat to 160℃ using a thermocompression press.
Molded in one piece with area pressure of 25Kg/ ^cm2 , total thickness of 3.6mm,
A plate-shaped reading device with a size of 400 x 450 mm was obtained.

A voltage of 500 VDC is applied to each conductive wire group D and E to attract the original paper, and the cursor is placed on the paper to activate the conductive wires D and E of the reading section.
I received it and checked the quality of the image on the display. The suction force was 6.5 g/cm ² , and the image reading performance of the original was good.

The above dielectric constant and volume resistivity are based on JIS K
Measured using 6911.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a typical example of a coordinate reading device of the present invention using an electromagnetic induction method. FIG. 2 is a perspective view showing a typical example of the electrostatic induction type coordinate reading device of the present invention. A...Surface dielectric layer, B...Intermediate dielectric layer, C
...Insulating substrate, D, E... Conductive wire group.

Claims (1)

[Claims] 1 A coordinate reading device that reads information on a document placed on its surface while suctioning and holding the document, which comprises an electrically insulating substrate, an intermediate dielectric layer provided on the substrate, and the intermediate dielectric layer. a surface dielectric layer provided thereon, a first conductive wire group parallel to each other is disposed on the substrate, and the positional relationship is such that the first conductive wire group is parallel to each other and orthogonal to the first conductive wire group. A second conductive wire group is disposed in the intermediate dielectric layer, and at least one of the conductive wire groups is connected to a DC power source to connect the intermediate dielectric layer and the surface dielectric layer. Electrostatic adsorption force is exerted on the document through the layers, and the position of a specific conductive wire is detected according to the information on the document by a group of conductive wires using an electromagnetic induction method or an electrostatic induction method. The coordinate reading device is adapted to be connected to a detection device that detects the coordinates.