JP7825816B2 - Eyeglasses and method of manufacturing eyeglasses - Google Patents

Description

The present invention relates to eyeglasses and a method for manufacturing eyeglasses.

Patent Document 1 discloses eyeglasses equipped with variable-focus lenses (ophthalmic lens parts) with a variable-focus function and a drive unit for driving the variable-focus lenses. These eyeglasses are configured so that the entire circumference of the variable-focus lenses for each eye is held by rims (eyeglass frames). These rims are connected by bridges (eyeglass frames), and endpieces (eyeglass frames) are provided on the horizontal outside of each rim, to which temple parts (eyeglass frames) are connected.

Japanese Patent Application Laid-Open No. 2007-240709

Generally, variable-focus lenses are small, with an effective lens diameter equal to or smaller than the diameter of the cornea of the wearer's eye. In eyeglasses that use such small variable-focus lenses as ophthalmic lenses, the holding structure that holds the variable-focus lens intrudes into the wearer's field of vision, causing the wearer to find the holding mechanism inconvenient and reducing convenience.
This problem is not limited to variable focus lenses, but can similarly occur with any eyeglasses that include a small eye lens portion.

In order to solve the above-mentioned problems, one aspect of the present invention is a pair of glasses having an ophthalmic lens portion, wherein a connecting member extending from a spectacle frame positioned outside the wearer's field of vision is connected to a connecting position on the outer edge of the ophthalmic lens portion, thereby supporting the ophthalmic lens portion by the spectacle frame, and the connecting position is located within a section of a plurality of sections obtained by dividing the optical axis of the ophthalmic lens portion into sections at predetermined angles on a virtual plane perpendicular to the optical axis, in which the frequency with which the wearer's line of sight falls is lower than the average value.
In general, eyeglasses have ophthalmic lens units positioned in front of the wearer's eyes, while the eyeglass frame supporting the ophthalmic lens units is positioned generally out of the wearer's field of vision. When a small ophthalmic lens unit such as a variable focus lens is supported by an eyeglass frame positioned out of the wearer's field of vision, a connecting member (retaining structure) connecting the eyeglass frame and the ophthalmic lens unit will be in the wearer's field of vision.
As a result of research, the inventors have found that the degree to which the wearer perceives the connecting member as a nuisance varies depending on the position of the connecting member in the wearer's field of vision (in the direction seen from the center of the field of vision). Therefore, by arranging the connecting member in a position in the wearer's field of vision (in the direction seen from the center of the field of vision) where the wearer perceives the connecting member as a nuisance to a lesser extent, it is possible to achieve a high effect of making the connecting member less likely to be perceived as a nuisance by the wearer.
Since a wearer usually changes their line of sight when wearing the eyeglasses, it is possible to identify a line of sight that the wearer rarely looks in by measuring how often the wearer looks in which direction. A direction that the wearer rarely looks in can be considered a direction in which the wearer feels the connecting member to be less of a nuisance. Therefore, by arranging the connecting member in a direction that the wearer rarely looks in, it is possible to achieve a high effect of making the connecting member less of a nuisance to the wearer.
Therefore, in the present eyeglasses, the connecting position where the connecting member extending from the eyeglass frame is connected to the ophthalmic lens portion is arranged within a section where the frequency of the wearer's line of sight falling therein is lower than the average among a plurality of sections obtained by dividing the optical axis of the ophthalmic lens portion into predetermined angle intervals on a virtual plane perpendicular to the optical axis of the ophthalmic lens portion. A section where the frequency of the wearer's line of sight falling therein is lower than the average can be said to be a section where the wearer's line of sight falls relatively infrequently. Therefore, by arranging the connecting member within a section where the frequency of the wearer's line of sight falling therein is lower than the average, as in the present eyeglasses, it is possible to obtain a high effect of making the connecting member less likely to be perceived as a nuisance by the wearer.
The frequency of each category to which the wearer's gaze direction belongs can be obtained, for example, by sampling the wearer's gaze direction under predetermined sampling conditions (e.g., sampling time interval, number of samples, assumed situation (while driving a vehicle such as a car or a bicycle, while outdoors, while reading, while playing a game, while using a smartphone, while using a computer, etc.)), obtaining the distribution of the gaze direction for the above-mentioned multiple categories, and calculating the ratio of the number of samples belonging to each category to the total number of samples.

In the eyeglasses, the specified angle may be 30° or more, and the connected position may be located within the lowest or second lowest frequency category among categories in which the wearer's line of sight belongs with a frequency lower than the average value.
If the number of divisions set around the optical axis is too large, the difference in frequency of the wearer's line of sight between adjacent divisions will not be clearly apparent, making it difficult to clearly identify a division that will provide a high level of effectiveness in making the wearer less likely to feel the connecting member as a nuisance. If the specified angle is 30° or more, as in the case of the present eyeglasses, the maximum number of divisions set around the optical axis is 12, making it easier to clearly identify a division that will provide a high level of effectiveness in making the wearer less likely to feel the connecting member as a nuisance. As a result, it is possible to clearly identify the least frequent division or the second least frequent division that will provide a high level of effectiveness in making the wearer less likely to feel the connecting member as a nuisance.

Another aspect of the present invention is eyeglasses having an ophthalmic lens portion, wherein a connecting member extending from an eyeglass frame positioned outside the wearer's field of vision is connected to a connecting position on the outer edge of the ophthalmic lens portion, thereby supporting the ophthalmic lens portion by the eyeglass frame, and the connecting position is located above a horizontal virtual line passing through the optical axis in a virtual plane perpendicular to the optical axis of the ophthalmic lens portion.
It is known that in daily life, wearers tend to look downward more frequently. For example, in daily life, there are many opportunities to walk indoors and outdoors, and at such times, wearers frequently look downward to watch their step. Therefore, by arranging the connecting member above a horizontal imaginary line passing through the optical axis of the ophthalmic lens portion, it is possible to obtain a high effect of making the connecting member less likely to be a nuisance to the wearer in daily life.

Yet another aspect of the present invention is eyeglasses having an ophthalmic lens portion, wherein a connecting member extending from an eyeglass frame positioned outside the wearer's field of vision is connected to a connecting position on the outer edge of the ophthalmic lens portion, thereby supporting the ophthalmic lens portion by the eyeglass frame, and the connecting position is located outside a vertical imaginary line passing through the optical axis in an imaginary plane perpendicular to the optical axis of the ophthalmic lens portion.
If the connecting member is positioned inside (toward the nose) a vertical imaginary line passing through the optical axis of the ophthalmic lens unit, the connecting member will intrude closer to the center of the field of view, making the wearer more likely to perceive the presence of the connecting member and find it intrusive. Furthermore, in everyday life, wearers generally often use eyeglasses to view nearby visual objects, such as while reading, playing games, or using a smartphone. When viewing such nearby visual objects, convergence causes both eyes to move inward (toward the nose). Therefore, if the connecting member is positioned inside (toward the nose) a vertical imaginary line passing through the optical axis of the ophthalmic lens unit, the connecting member will intrude more into the field of view when viewing nearby visual objects, making the wearer more likely to find the connecting member intrusive.
With these glasses, the connecting member is positioned outside the vertical imaginary line passing through the optical axis of the ophthalmic lens portion (on the side farther from the nose, i.e., toward the ear), which is highly effective in making the connecting member less likely to be a nuisance to the wearer when viewing nearby visual objects.

In the eyeglasses, the connecting member may extend from a temple portion of the eyeglass frame that is placed over the wearer's ear.
This allows the connecting member extending from the temple portion to enter the wearer's field of vision from the horizontal outside (ear side) and be connected to a connecting position located outside (ear side) of a vertical imaginary line passing through the optical axis of the ophthalmic lens portion.

In addition, in the eyeglasses, the connected position may be located outside a vertical imaginary line passing through the optical axis and above a horizontal imaginary line passing through the optical axis in an imaginary plane perpendicular to the optical axis of the ophthalmic lens portion.
As described above, wearers generally have many opportunities to walk indoors and outdoors in their daily lives, and frequently look downward to keep an eye on their feet. Furthermore, as described above, wearers generally use eyeglasses to view nearby visual objects, such as while reading, playing games, or using a smartphone, causing their eyes to converge inward (toward the nose). With these eyeglasses, the connecting position is located below a horizontal imaginary line passing through the optical axis and away from a vertical imaginary line passing through the optical axis, which is where the eyes tend to be directed in daily life. This effectively prevents the connecting member from becoming a nuisance to the wearer in many everyday situations.

In addition, in the eyeglasses, the thickness of the connecting member in a direction perpendicular to the axial direction of the connecting member and the optical axis direction of the ophthalmic lens portion may be thinner than the thickness of the ophthalmic lens portion in the optical axis direction.
This allows the connecting member to have a cross-sectional area large enough to ensure the strength required for the connecting member, while narrowing the area that the connecting member occupies in the wearer's field of vision compared to connecting members with a circular or regular polygonal cross section, making it even less likely that the connecting member will be perceived as a nuisance by the wearer.

In the eyeglasses, the effective lens diameter of the ophthalmic lens portion may be equal to or smaller than the diameter of the cornea of the wearer's eye.
In the case of an ophthalmic lens portion whose effective lens diameter is equal to or smaller than the corneal diameter of the wearer's eye, the connecting members will be largely contained within the wearer's field of vision, which has the great advantage of making the connecting members less likely to be perceived as a nuisance by the wearer.

In the eyeglasses, the ophthalmic lens portion may be configured by a variable focus lens.
Variable focus lenses are generally small, and when a variable focus lens is used as an ophthalmic lens, many connecting members tend to enter the wearer's field of vision, so there is a great advantage in that the connecting members are less likely to be perceived as a nuisance by the wearer.

Furthermore, yet another aspect of the present invention is a method for manufacturing eyeglasses in which an eye lens portion is supported by an eyeglass frame by connecting a connecting member extending from the eyeglass frame located outside the wearer's field of vision to a connecting position on the outer edge of the eye lens portion, the method comprising: a sampling step for sampling the wearer's gaze direction under predetermined sampling conditions; a specifying step for identifying, from among a plurality of sections obtained by dividing a virtual plane perpendicular to the optical axis of the eye lens portion into predetermined angle intervals around the optical axis, a section to which the wearer's gaze direction sampled in the sampling step belongs with a frequency lower than the average value; and a determination step for determining the connecting position so that the connecting position is located within the section specified in the specifying step.
As described above, by placing the connecting member in a position in the wearer's field of vision (in the direction viewed from the center of the field of vision) where the wearer feels the connecting member to be less of a nuisance, it is possible to achieve a high effect of making the connecting member less likely to be a nuisance to the wearer.
Since a wearer usually changes their line of sight when wearing the eyeglasses, it is possible to identify a line of sight that the wearer rarely looks in by measuring how often the wearer looks in which direction. A direction that the wearer rarely looks in can be considered a direction in which the wearer feels the connecting member to be less of a nuisance. Therefore, by arranging the connecting member in a direction that the wearer rarely looks in, it is possible to achieve a high effect of making the connecting member less of a nuisance to the wearer.
Therefore, in this manufacturing method, the connecting position where the connecting member extending from the eyeglass frame is connected to the ophthalmic lens portion is arranged within a section where the frequency of the wearer's line of sight falling therein is lower than the average among a plurality of sections obtained by dividing the optical axis of the ophthalmic lens portion into predetermined angle intervals on a virtual plane perpendicular to the optical axis of the ophthalmic lens portion. A section where the frequency of the wearer's line of sight falling therein is lower than the average can be said to be a section where the wearer's line of sight falls relatively infrequently. Therefore, by arranging the connecting member within a section where the frequency of the wearer's line of sight falling therein is lower than the average, as in the present eyeglasses, it is possible to obtain a high effect of making the connecting member less likely to be perceived as a nuisance by the wearer.
The frequency of each category to which the wearer's gaze direction belongs is obtained by sampling the wearer's gaze direction under predetermined sampling conditions (e.g., sampling time interval, number of samples, assumed situation (while driving a vehicle such as a car or a bicycle, while doing outdoor activities, while reading, while playing a game, while using a smartphone, while using a computer, etc.)), obtaining the distribution of the gaze direction for the above-mentioned multiple categories, and calculating the ratio of the number of samples belonging to each category to the total number of samples.
Depending on the intended situation of the eyeglasses, it is conceivable that the category in which the frequency of the wearer's gaze direction falls below the average value may differ significantly for each wearer. In such cases, it is possible to identify the category by individually sampling each wearer and place a connecting member in that category, thereby making it possible to create eyeglasses dedicated to each wearer.

This invention is highly effective in preventing the wearer from feeling that the connecting member is a nuisance when wearing eyeglasses with a small ophthalmic lens portion.

FIG. 1 is a front view schematically showing the configuration of eyeglasses according to an embodiment. FIG. 2 is a plan view schematically showing the configuration of the eyeglasses. FIG. 2 is a cross-sectional view showing a schematic configuration of a variable focus lens in the eyeglasses. FIG. 2 is a plan view showing a schematic configuration of a variable focus lens in the eyeglasses. FIG. 2 is a block diagram showing the configuration of a control device in the glasses. 5A and 5B are explanatory diagrams showing examples of cross-sectional shapes of a connecting member in the eyeglasses. FIG. 10 is a diagram showing an example of a gaze direction distribution plotting the results of sampling the gaze direction of the left eye of a wearer wearing the eyeglasses while driving a car with the driver's seat in the right seat. FIG. 10 is a front view showing a modified example in which the connecting member is connected to the variable-focus lens at a different connection position. FIG. 10 is a front view showing a modified example in which the connecting member extends from the temple portion.

Hereinafter, an embodiment in which the present invention is applied to eyeglasses having an ophthalmic lens portion will be described.
In this embodiment, an example will be described in which the ophthalmic lens portion is a variable focus lens, but the ophthalmic lens portion is not limited to a variable focus lens as long as it is a small ophthalmic lens portion (for example, an ophthalmic lens portion whose effective lens diameter is equal to or smaller than the corneal diameter of the wearer's eye).

FIG. 1 is a front view showing a schematic configuration of eyeglasses 1 according to this embodiment, and FIG. 2 is a plan view showing a schematic configuration of eyeglasses 1 according to this embodiment.
The eyeglasses 1 in this embodiment include an eyeglass frame 2, a pair of left and right variable focus lenses 3, 3 as ophthalmic lens units, and a control device 10 as a lens control device that controls the focal length of the variable focus lenses 3, 3.

The eyeglass frame 2 comprises a bridge portion 4, a pair of left and right connecting members 6, 6, a nose pad portion 7, a pair of left and right end pieces 8, 8, and a pair of left and right temple portions 9, 9.

The bridge portion 4 is positioned above and out of the wearer's field of vision when worn, and supports the left and right connecting members 6, 6 that hold the variable-focus lenses 3, 3. The bridge portion 4 extends laterally between the left and right end pieces 8, 8, with the end pieces 8, 8 attached to both left and right ends of the bridge portion 4. The bridge portion 4 preferably supports the connecting member 6 so that the connecting member 6 can move laterally, and is equipped with an inter-lens distance adjustment unit that can adjust the inter-lens distance D between the pair of left and right variable-focus lenses 3, 3 held by the connecting member 6. The inter-lens distance D can be determined, for example, by the distance between reference positions on the variable-focus lenses 3, 3 (e.g., the center positions of the variable-focus lenses 3, 3). Here, the reference position of the variable-focus lenses 3, 3 is, for example, equal to the optical center position of the variable-focus lenses 3, 3, and the inter-lens distance D is equal to the distance between the optical centers of each variable-focus lens 3, 3.

The connecting members 6, 6 are members that hold the variable-focus lenses 3, 3 and have an elongated (linear) shape. Specifically, the connecting members 6, 6 in this embodiment are formed from a plastically deformable wire member. The connecting member 6 in this embodiment extends from the bridge portion 4 of the eyeglass frame 2, and its tip connects to the connecting position 3a on the outer edge of the variable-focus lens 3, thereby holding the variable-focus lens 3. The connecting member 6 is supported by the bridge portion 4 via the sliding portion 4a, which forms the inter-lens distance adjustment unit. Specifically, the sliding portion 4a is a member that holds the connecting member 6 slidably in the left-right direction relative to the bridge portion 4. In this embodiment, the sliding portion 4a is a hollow member into which the bridge portion 4 is inserted and is attached to the bridge portion 4 so that it can slide along the longitudinal direction of the bridge portion 4.

By providing an inter-lens distance adjustment unit, the inter-lens distance D of the variable-focus lenses 3, 3 can be adjusted to match the inter-pupillary distance PD of the user in a normal viewing state. When the variable-focus lenses 3, 3 are smaller than normal eyeglass lenses, as in this embodiment, it is beneficial to be able to adjust the inter-lens distance D of the variable-focus lenses 3, 3 for each user to match the user's inter-pupillary distance PD. Note that the configuration of the inter-lens distance adjustment unit is not limited to that of this embodiment.

The nose pad 7 is held by the bridge portion 4 and is a component that abuts against the user's nose when the user wears the eyeglasses 1, thereby positioning the eyeglasses 1.

The end pieces 8, 8 are members that connect the bridge piece 4 and the temple pieces 9, 9. In this embodiment, the end pieces 8, 8 include an attachment portion 8a that is attached to the end of the bridge piece 4, and a hinge portion 8b that rotatably supports the temple piece 9.

The temples 9, 9 are components that are placed over the user's ears when the user wears the eyeglasses 1. In this embodiment, the left and right temples 9, 9 are configured so that they can be folded toward the center of the eyeglasses 1 in the left-right direction by means of the hinges 8b provided on the end pieces 8, 8.

The variable-focus lenses 3, 3 in this embodiment are not limited to this configuration, as long as they have an electrically controllable focal length change function. However, it is preferable that the variable-focus lenses 3, 3 are shape-variable lenses whose focal length changes by changing the shape of their refractive surface. Among shape-variable lenses, liquid lenses (also known as electrowetting devices) are preferred, in which the refractive surface is the interface between two types of liquid, and the focal length can be changed by electrically controlling the wettability of the liquid to change the shape of the interface. Liquid lenses allow for high-speed, highly flexible control of the focal length.

The variable-focus lenses 3, 3 of this embodiment use liquid lenses whose effective lens diameter is equal to or smaller than the diameter of the cornea of the wearer's eye, specifically, liquid lenses with an effective lens diameter (diameter) of approximately 5 mm to 12 mm. Furthermore, by using a larger variable-focus lens, the range of the user's line of sight that can be covered by the variable-focus lens can be expanded, improving user convenience.

FIG. 3 is a cross-sectional view showing a schematic configuration of the variable-focus lens 3 in this embodiment.
FIG. 4 is a plan view showing a schematic configuration of the variable-focus lens 3 in this embodiment.
As shown in Figure 3, the variable-focus lens 3 of this embodiment has a configuration in which an insulating liquid 311 and a conductive liquid 312, which are in contact with each other in an unmixed state at an interface I, are sealed between an annular first electrode 301 and two transparent window members 303, 304 that close the upper and lower ends of the first electrode 301. The insulating liquid 311 is, for example, an oil-based liquid, and the conductive liquid 312 is, for example, an aqueous liquid with relatively low conductivity. A voltage V0 is applied to the first electrode 301, but in this embodiment, V0 = 0 V because the annular first electrode 301 is grounded. The first electrode 301 is also insulated from the sealed insulating liquid 311 and conductive liquid 312 by an insulating layer 301a.

Furthermore, the variable-focus lens 3 of this embodiment has multiple pairs of second electrodes 302A, 302B, ... arranged at symmetrical positions with respect to the axis O of the first electrode 301. In this embodiment, as shown in FIG. 4, four pairs of second electrodes 302A to 302H are arranged on a circumference centered on the axis O, for a total of eight second electrodes 302A to 302H.

As shown in Figure 3, the second electrodes 302A-302H are positioned so that they contact the conductive liquid 312. When voltages VA-VH are applied to each of the second electrodes 302A-302H, a potential difference is generated between each of the second electrodes 302A-302H and the first electrode 301, and the electrowetting effect causes the end Ia of the insulating liquid 311 (the end Ia of interface I) to be displaced along the insulating layer portion 301b on the first electrode 301. This displacement of the end Ia of the insulating liquid 311 changes the shape of the insulating liquid 311, changing the curvature of the interface I. Therefore, by controlling the voltages VA-VH applied to the second electrodes 302A-302H, the focal length of the variable-focus lens 3, which uses the interface I as a refractive surface, can be changed.

In particular, the variable-focus lens 3 of this embodiment can transform the refractive interface I into a diffusing lens (concave lens), a flat lens, or a condensing lens (convex lens) by controlling the voltages VA to VH applied to the second electrodes 302A to 302H. Therefore, the eyeglasses 1 of this embodiment can be used as eyeglasses for myopic users by using the variable-focus lens 3 as a diffusing lens (concave lens), and can be used as eyeglasses for hyperopic users by using the variable-focus lens 3 as a condensing lens (convex lens).

The variable-focus lens 3 of this embodiment can change its focal length in a range of -15D to +15D in diopter terms (the reciprocal of the focal length). By using a variable-focus lens 3 with such a wide range of focal length changes, it is possible to accommodate users with low vision, such as those with amblyopia.

In this embodiment, by applying the same voltage to all second electrodes 302A-302H arranged symmetrically with respect to the axis O of the first electrode 301, the focal length can be changed while keeping the optical axis of the variable-focus lens 3 aligned with the axis O of the first electrode 301. On the other hand, by applying different voltages to each of the second electrodes 302A-302H, it is possible not only to change the focal length but also to shift or tilt the optical axis of the variable-focus lens 3. In other words, the variable-focus lens 3 of this embodiment can change either the position or direction of the optical axis, or both, by controlling the applied voltages VA-VH.

As shown in Figure 1, the control device 10 is provided, together with the battery 20, in one of the left and right end pieces 8, 8 (the left end piece 8 in the figure). The control device 10 can control the focal length of the variable-focus lens 3 by controlling the voltage applied from the battery 20 to each of the second electrodes 302A-302H of the variable-focus lens 3.

FIG. 5 is a block diagram showing the configuration of the control device 10 in this embodiment.
The control device 10 in this embodiment includes a main control unit 11, a voltage changing unit 12, an operation unit 13, and a memory unit 14. The control device 10 is connected to the second electrodes 302A to 302H of the variable-focus lens 3 and a battery 20 as a power source for supplying voltage.

The main control unit 11 is configured, for example, by a control board (computer) equipped with a CPU, RAM, ROM, etc., and performs overall control of the eyeglass lens device, that is, the eyeglasses 1, by executing a predetermined control program stored in the ROM. In particular, in this embodiment, the main control unit 11 functions as a control unit (control means) that controls the variable-focus lens 3 so as to change the focal length of the variable-focus lens 3, 3 based on operation instructions received by the operation unit 13.

Under the control of the main control unit 11, the voltage change unit 12 changes the voltage applied from the battery 20 to each of the second electrodes 302A-302H of the variable-focus lens 3. The voltage change unit 12 can change the voltage applied to each of the second electrodes 302A-302H individually for each of the second electrodes 302A-302H. However, the voltage change unit 12 may also be capable of partially changing only some of the second electrodes 302A-302H (for example, only one pair of second electrodes).

When operated by a user, the operation unit 13 outputs an operation signal indicating the user's operation to the main control unit 11. Examples of user operations accepted by the operation unit 13 include power on/off operations, execution instructions for the main control unit 11, and changes to the control content of the main control unit 11. The operation unit 13 is composed of an operating device of a type appropriate for the accepted user operation (mechanical or electrostatic touch buttons, rotary operation devices such as dials, etc.). Note that it is also possible to configure the device so that these user operations are not required, in which case the operation unit 13 can be omitted.

The memory unit 14 stores programs and data used by the control device 10. In particular, in this embodiment, it stores measurement information on the focal length of the variable-focus lens that suits the user as data used to control the focal length of the variable-focus lenses 3, 3, which will be described later.

The battery 20 functions as a power source for the control device 10 and outputs a voltage to be supplied to the second electrodes 302A-302H of the variable-focus lens 3. The battery 20 may be a primary battery or a secondary battery. It may also be equipped with a power generation function, such as a solar panel.

In this embodiment, when the operation unit 13 receives a power-on operation from the user, if the setting of the basic focal length of the variable-focus lens 3 has not been completed, the basic focal length is set. Note that, in this example, the power is turned on when the operation unit 13 receives a power-on operation from the user, but this is not limiting. For example, a wear detection unit may be provided that detects when the eyeglasses 1 are worn by the user, and the power may be turned on when it detects that the eyeglasses 1 are worn by the user.

The basic focal length can be set arbitrarily depending on the intended use of the user of the glasses 1 (the distance at which the user views the visual object). For example, when the user uses the glasses 1 to view a nearby visual object (smartphone, tablet, game console, book, etc.), the basic focal length is set to a focal length that brings this nearby visual object into focus. Conversely, when the user uses the glasses 1 to view a distant visual object (distant video (movies, etc.), artwork or other objects of appreciation, scenery, etc.), the basic focal length is set to a focal length that brings this distant visual object into focus.

The basic focal length may also be set to a fixed focal length for each user, regardless of the intended use of the eyeglasses 1. For example, for a user with an eye abnormality, including refractive errors such as myopia, hyperopia, or astigmatism, the basic focal length is set to a focal length corresponding to the user's prescribed refractive power (basic refractive power). In this case, for example, for a myopic user, the focal length corresponding to minus refractive power is set as the basic focal length.

The basic focal length can be set by a professional or the user themselves by operating the operation unit 13. For example, if the operation unit 13 is equipped with a dial indicating the refractive power, the basic focal length can be set by turning the dial to match the user's prescribed refractive power. In this case, an electrical signal (operation signal) corresponding to the rotation position of the dial is sent to the main control unit 11, which controls the voltage change unit 12 so that a voltage corresponding to this signal is applied to the second electrodes 302A-302H of the variable-focus lens 3. This changes the shape of the interface I between the insulating liquid 311 and the conductive liquid 312 in the variable-focus lens 3, changing the curvature of the interface I and changing the focal length of the variable-focus lens 3 to the set basic focal length. This basic focal length information is stored in the memory unit 14 as measurement information for the focal lengths of the variable-focus lenses 3, 3 that are suited to the user.

Next, the holding mechanism (connecting members 6, 6) for the variable-focus lenses 3, 3 in this embodiment will be described.
Because the variable-focus lenses 3, 3 of the present eyeglasses 1 are small, the connecting members 6, 6 that hold the variable-focus lenses 3, 3 intrude into the wearer's field of vision. In this embodiment, the connecting members 6, 6 are made of thin, linear members (wire members), thereby narrowing the area of the wearer's field of vision occupied by the connecting members 6, 6. Furthermore, because the tips of the connecting members 6, 6 are connected to a portion of the outer edge of the variable-focus lenses 3, 3 (connected position 3 a), the position of the connecting members 6, 6 (the center of the field of vision = the direction as seen from the lens axis O) is limited to a limited position (limited direction) in the wearer's field of vision. This configuration makes it possible to make the connecting members 6, 6 less likely to be a nuisance to the wearer when wearing the eyeglasses 1.

In particular, as shown in Figures 6(a) and (b), the connecting members 6,6 of this embodiment have a thickness T1 in the direction (left-right direction in Figure 6) perpendicular to the axial direction of the connecting members (direction perpendicular to the plane of the page in Figure 6) and the optical axis direction of the variable-focus lenses 3,3 (up-down direction in Figure 6) that is thinner than the thickness T2 in the optical axis direction of the variable-focus lenses 3,3 (T1 < T2). This ensures a cross-sectional area sufficient to ensure the strength required for the linear connecting members 6,6, while narrowing the area of the wearer's field of vision that the connecting members 6,6 occupy compared to linear connecting members 6,6 with a circular or regular polygonal cross section. This makes it even less likely that the connecting members will be perceived as a nuisance by the wearer.

However, simply using linear connecting members 6,6 to hold the variable-focus lenses 3,3 may not be effective enough to reduce the wearer's perception of the connecting members 6,6 as a nuisance. As a result of research, the inventors discovered that the degree to which the wearer perceives the connecting members 6,6 as a nuisance varies depending on the position of the linear connecting members 6,6 in the wearer's field of vision (the direction from the center of the field of vision = the lens axis O). Therefore, by positioning the linear connecting members 6,6 in a position in the wearer's field of vision where the wearer perceives the connecting members 6,6 as a nuisance to a minimum (the direction from the center of the field of vision = the lens axis O), it is possible to achieve a significant effect of reducing the wearer's perception of the connecting members 6,6 as a nuisance.

Since a wearer typically changes their line of sight when wearing the eyeglasses 1, it is possible to identify a line of sight that the wearer rarely looks in by measuring how often they look in which direction. A direction that the wearer rarely looks in can be considered a direction in which the wearer will find the connecting members 6, 6 to be less of a nuisance. Therefore, by arranging the linear connecting members 6, 6 in a direction that the wearer rarely looks in, it is possible to achieve a significant effect of making the connecting members 6, 6 less likely to be a nuisance to the wearer.

In this embodiment, therefore, the connected positions 3a where the tips of the connecting members 6, 6 extending from the bridge portion 4 of the eyeglass frame 2 are connected to the respective variable-focus lenses 3, 3 are arranged within a section where the frequency of the wearer's line of sight falling is lower than the average, out of multiple sections obtained by dividing the optical axis O of the variable-focus lenses 3, 3 into sections at predetermined angles on an imaginary plane perpendicular to the optical axis O. A section where the frequency of the wearer's line of sight falling is lower than the average can be said to be a section where the wearer's line of sight is relatively infrequently directed. Therefore, by arranging the linear connecting members 6, 6 within a section where the frequency of the wearer's line of sight falling is lower than the average, as in this embodiment, it is possible to achieve a significant effect of making the connecting members 6, 6 less likely to be perceived as a nuisance by the wearer.

7 is a diagram showing an example of a gaze direction distribution plotting the results of sampling the gaze direction of the wearer's left eye when the wearer is driving a car with the driver's seat in the right seat (after driving for about one hour) wearing the eyeglasses 1. Note that similar results are obtained for the right eye, so a description thereof will be omitted.
In the sampling process of sampling the gaze direction of the wearer, for example, gaze data of a driver (wearer) actually driving a standard passenger car on an ordinary road is measured at a measurement rate of 60 scans per second using a known gaze measurement device (for example, "faceLAB 5" manufactured by Seeing Machines, Inc.). This makes it possible to obtain gaze data consisting of a horizontal gaze angle and a vertical gaze angle, as shown in Fig. 7. Note that the sampling conditions are not limited to these and may be changed as appropriate.

Then, as shown in Figure 7, an identification process is performed in which eight sections (sections 1 to 8) are obtained by dividing the optical axis O of the variable-focus lenses 3, 3 into predetermined angle increments (45° increments in this embodiment) on a virtual plane (the plane of the paper in Figure 7) perpendicular to the optical axis O. This identifies sections to which the wearer's gaze data (each plot) sampled in the sampling process belongs with a frequency lower than the average value. The frequency of each section to which the wearer's gaze direction belongs can be obtained by calculating the ratio of the number of samples belonging to each section to the total number of samples (e.g., 200,000). The average value is obtained by dividing the total number of samples (e.g., 200,000) by the number of sections (8).

In this embodiment, the number of divisions is eight, but the number of divisions (the predetermined angle dividing the area around the optical axis O) can be set arbitrarily. For example, the predetermined angle may be set to 30° to obtain 12 divisions. However, if the number of divisions is too large, it becomes difficult to clearly see the difference in frequency to which the wearer's gaze data belongs between adjacent divisions, so it is preferable to set the predetermined angle to 30° or more. It is preferable to set the lower limit of the number of divisions to four (predetermined angle = 90°).

In the example shown in Figure 7, the categories in which the wearer's gaze data (each plot) falls with a frequency lower than the average are Category 1, Category 2, and Category 3, with the frequencies in Categories 2 and 3 being particularly low. Therefore, by configuring the connected position 3a to be located in Category 1, Category 2, or Category 3, and particularly Category 2 or Category 3, it is possible to achieve a significant effect of making the connecting members 6, 6 less likely to be perceived as a nuisance by the wearer.

Here, if the connecting members 6,6 were positioned inside (towards the nose) a vertical imaginary line passing through the optical axis O of the variable-focus lenses 3,3, the connecting members would be closer to the center of the field of view, making the wearer more likely to perceive the presence of the connecting members 6,6 and find them to be a nuisance. For this reason, the variable-focus lens 3 for the left eye in this embodiment is configured so that, of sections 2 and 3, the connected position 3a is positioned in section 3, which is located outside (farther from the nose, i.e., towards the ear) a vertical imaginary line passing through the optical axis O, rather than in section 2, which is located inside the vertical imaginary line passing through the optical axis O.

For the same reason, the variable-focus lens 3 for the right eye is configured so that the coupling position 3a is located within segment 2, which is located outside (towards the ear) of the vertical imaginary line passing through the optical axis O, rather than segment 3, which is located inside (towards the nose) of the vertical imaginary line passing through the optical axis O.

As a result, the connecting positions 3a, 3a of the variable focus lenses 3, 3 to which the connecting members 6, 6 are connected in the eyeglasses 1 of this embodiment are as shown in Figure 1.

The gaze direction distribution diagram shown in Figure 7 is for a situation in which a wearer of the eyeglasses 1 is driving a car, so the frequency of category 4, which includes the gaze direction for viewing the rearview mirror, is relatively high. However, in everyday life, wearers of the eyeglasses 1 are known to gaze downward more frequently, and when not driving a car, the frequency of category 4 drops to the same frequency as category 1.

In such a case, for example, as shown in Figure 8, the variable focus lens 3 for the left eye may be configured so that the coupling position 3a is located within section 4, and the variable focus lens 3 for the right eye may be configured so that the coupling position 3a is located within section 1.

Furthermore, in everyday life, wearers generally often use the eyeglasses 1 when viewing nearby objects, such as while reading, playing games, or using a smartphone. When viewing such nearby objects, convergence causes both eyes to move inward (toward the nose). Therefore, if the connecting members 6, 6 are positioned inside a vertical imaginary line passing through the optical axis O of the variable-focus lenses 3, 3, the connecting members 6, 6 will intrude into the field of view when viewing nearby objects, making the wearer more likely to find the connecting members 6, 6 to be a nuisance.

In such cases, as shown in Figures 1 and 8, for the variable-focus lens 3 for the left eye, the connecting position 3a may be located in section 5 or 6, not just section 3 or 4. Similarly, for the variable-focus lens 3 for the right eye, the connecting position 3a may be located in section 7 or 8, not just section 1 or 2. Even in this case, since the connecting member 6 is located outside (towards the ear) the vertical imaginary line passing through the optical axis O of the variable-focus lens 3 for the left eye, it is possible to achieve a significant effect of making the connecting members 6, 6 less likely to get in the way of the wearer when viewing a nearby visual object.

However, if it is desired to achieve a high degree of effectiveness in making the connecting members 6, 6 less likely to be perceived as a nuisance by the wearer in various situations in daily life, it is preferable to avoid placing the connected positions 3a, 3a below the horizontal imaginary line passing through the optical axis O. Therefore, in this case, it is preferable to place the connected positions 3a, 3a outside (toward the ear) the vertical imaginary line passing through the optical axis O and above the horizontal imaginary line passing through the optical axis. Specifically, for a variable-focus lens 3 for the left eye, it is preferable to place the connected positions 3a in section 3 or section 4 shown in Figure 7, and for a variable-focus lens 3 for the right eye, it is preferable to place the connected positions 3a in section 1 or section 2 shown in Figure 7.

In this embodiment, the connecting members 6, 6 extend from the bridge portion 4 of the eyeglass frame 2, but as shown in Figure 9, they may also extend from the temple portions 9, 9 of the eyeglass frame 2. This allows the connecting members 6, 6 extending from the temple portions 9, 9 to enter the wearer's field of vision from the horizontal outside (ear side) and be connected to a connected position 3a located outside a vertical imaginary line passing through the optical axis O of the variable-focus lenses 3, 3. In this case, it is possible to achieve an even greater effect of making the connecting members 6, 6 less likely to be perceived as a nuisance by the wearer.

DESCRIPTION OF SYMBOLS 1: Eyeglasses 2: Eyeglass frame 3: Variable focus lens 3a: Connected position 4: Bridge portion 4a: Slide portion 6: Connecting member 7: Nose pad portion 8: End piece portion 8a: Mounting portion 8b: Hinge portion 9: Temple portion 10: Control device 11: Main control unit 12: Voltage change unit 13: Operation unit 14: Memory unit 20: Battery 301: First electrode 301a, 301b: Insulating layer 302A to 302H: Second electrode 303, 304: Window member 311: Insulating liquid 312: Conductive liquid D: Lens distance I: Interface Ia: End O: Axis PD: Interpupillary distance

Claims (7)

A pair of eyeglasses including a small eye lens portion that is made up of a variable focus lens and has an outer edge portion that is positioned within the wearer's field of vision ,
a connecting member extending from a spectacle frame positioned outside the wearer's field of vision is connected to a connecting position of the outer edge portion of the ophthalmic lens portion, whereby the ophthalmic lens portion is supported by the spectacle frame;
The coupling position is arranged in an upper section of four sections, namely, top, bottom, left, and right , obtained by dividing the optical axis into 90-degree sections on a virtual plane perpendicular to the optical axis of the ophthalmic lens part ,
The eyeglasses, characterized in that the only member connected to the outer edge portion of the ophthalmic lens portion is the connecting member . The eyeglasses according to claim 1 ,
The eyeglasses, characterized in that the connected position is located outside a vertical imaginary line passing through the optical axis of the ophthalmic lens portion on an imaginary plane perpendicular to the optical axis of the ophthalmic lens portion. The eyeglasses according to claim 2 ,
The eyeglasses, characterized in that the connecting member extends from a temple portion of the eyeglass frame that is placed over the wearer's ear . The eyeglasses according to any one of claims 1 to 3 ,
The eyeglasses are characterized in that the thickness of the connecting member in a direction perpendicular to the axial direction of the connecting member and the optical axis direction of the eye lens portion is thinner than the thickness of the eye lens portion in the optical axis direction. The eyeglasses according to any one of claims 1 to 4 ,
The eyeglasses are characterized in that the effective diameter of the ophthalmic lens portion is equal to or smaller than the diameter of the cornea of the wearer's eye . A method for manufacturing eyeglasses in which a connecting member extending from an eyeglass frame positioned outside a wearer 's field of vision is connected to a connecting position of an outer edge portion of a small-sized ophthalmic lens portion positioned within the wearer's field of vision , thereby supporting the ophthalmic lens portion by the eyeglass frame,
a sampling step of sampling the gaze direction of a wearer under predetermined sampling conditions;
a specifying step of specifying a section in which the frequency of the wearer's line of sight sampled in the sampling step belongs to is lower than an average value, from among a plurality of sections obtained by dividing a virtual plane perpendicular to the optical axis of the ophthalmic lens part into sections at predetermined angles around the optical axis;
a determining step of determining the connection position so that the connection position is located within the section identified in the identifying step. 7. The method for manufacturing eyeglasses according to claim 6,
The predetermined angle is 30° or more,
The method for manufacturing eyeglasses, wherein the specifying step specifies the lowest or second lowest frequency category among categories in which the wearer's gaze direction belongs with a frequency lower than the average value.