Electrostatic input device

Abstract

This electrostatic input device comprises: an insulating substrate; a plurality of electrostatic sensor electrodes arranged in a grid pattern on the insulating substrate; a plurality of LEDs mounted on the insulating substrate for each electrostatic sensor electrode; a light guide plate superimposed on the insulating substrate; and a panel that is superimposed on the light guide plate and has a plurality of transparent regions facing the plurality of electrostatic sensor electrodes, respectively, and a light-shielding region provided in a portion other than the plurality of transparent regions. The light guide plate has a plurality of light-shielding through-holes formed therein. Each of the plurality of light-shielding through-holes is provided at a position overlapping the light-shielding region of the panel, has a bent shape surrounding a first corner portion of each electrostatic sensor electrode in a plan view, and is spaced apart from the other light-shielding through-holes.

Description

Capacitive Input Device

[0001] The present invention relates to an electrostatic input device.

[0002] The following Patent Document 1 discloses a technology in which a light guide plate is provided below a plurality of operation keys, and light is irradiated onto the light guide plate from an LED provided on the side of the light guide plate, thereby causing the plurality of operation keys to emit light through the light guide plate.

[0003] Japanese Patent Application Laid-Open No. 2014-099245

[0004] However, the technology of Patent Document 1 does not allow multiple operation keys to emit light individually. Also, if the technology of Patent Document 1 is improved so that multiple operation keys can emit light individually, when a specific operation key is made to emit light, there is a risk that light will leak through the light guide plate to other operation keys adjacent to that specific operation key, causing those other operation keys to emit light as well.

[0005] Furthermore, in the technology of Patent Document 1, multiple operation keys are illuminated collectively, making it difficult for the operator to visually determine which of the multiple operation keys has been selected.

[0006] An electrostatic input device according to one embodiment includes an insulating substrate, a plurality of electrostatic sensor electrodes arranged in a grid pattern on the insulating substrate, a plurality of LEDs mounted on the insulating substrate for each electrostatic sensor electrode, a light guide plate overlaid on the insulating substrate, and a panel overlaid on the light guide plate, the panel having a plurality of transparent regions facing each of the electrostatic sensor electrodes and a light-shielding region provided in a portion other than the transparent regions, wherein the light guide plate has a plurality of light-shielding through holes formed therein, each of the light-shielding through holes being positioned so as to overlap with the light-shielding region of the panel, having a bent shape surrounding a first corner of the electrostatic sensor electrode in a planar view, and being provided separately from the other light-shielding through holes.

[0007] Moreover, an electrostatic input device according to one embodiment includes an insulating substrate, a plurality of electrostatic sensor electrodes arranged in a grid pattern on the insulating substrate, a plurality of LEDs mounted on the insulating substrate for each electrostatic sensor electrode, a light guide plate superimposed on the insulating substrate, a panel having a plurality of operation keys superimposed on the light guide plate and facing each of the plurality of electrostatic sensor electrodes, and a control circuit that controls the emission of the plurality of LEDs, wherein the control circuit identifies one of the plurality of operation keys that is close to the operating body based on the capacitance value of each of the plurality of electrostatic sensor electrodes, and controls the emission of the plurality of LEDs so that the brightness of other operation keys adjacent to the identified operation key is higher than the brightness of other operation keys that are not adjacent to the identified operation key.

[0008] According to one embodiment of the electrostatic input device, multiple transparent areas can be individually illuminated through a light guide plate, and when one transparent area is illuminated, leakage of light into other transparent areas adjacent to the one transparent area can be suppressed.

[0009] Furthermore, according to the electrostatic input device of one embodiment, the operator can easily visually grasp which of the plurality of operation keys has been selected.

[0010] 1 is a perspective view of the appearance of an electrostatic input device according to an embodiment; 2 is an exploded perspective view of an electrostatic input device according to an embodiment; 3 is a plan view of an insulating substrate included in an electrostatic input device according to an embodiment; 4 is a plan view of a light guide plate included in an electrostatic input device according to an embodiment; 5 is a partial enlarged view of the light guide plate shown in FIG. 4; 6 is a plan view of a light guide plate and an insulating substrate (overlapping each other) included in an electrostatic input device according to an embodiment; FIG. 1 shows a second modified example of the configuration of the light-blocking through holes in the electrostatic input device according to the embodiment. FIG. 2 shows a third modified example of the configuration of the light-blocking through holes in the electrostatic input device according to the embodiment. FIG. 3 shows a configuration of a light-emitting control system provided in the electrostatic input device according to the embodiment. FIG. 4 shows a fourth example of the light-emitting control method in the electrostatic input device according to the embodiment. FIG. 5 shows a fifth example of the light-emitting control method in the electrostatic input device according to the embodiment.

[0011] An embodiment will be described below with reference to the drawings. For convenience, in the following description, the Z-axis direction in the drawings is the up-down direction, the X-axis direction in the drawings is the left-right direction, and the Y-axis direction in the drawings is the front-rear direction. However, the positive Z-axis direction is the up direction, the positive X-axis direction is the right direction, and the positive Y-axis direction is the front.

[0012] (Outline of Capacitive Input Device 10) FIG. 1 is a perspective view showing the appearance of a capacitive input device 10 according to an embodiment.

[0013] 1, the electrostatic input device 10 is thin in the vertical direction (Z-axis direction) and has a rectangular shape with its longitudinal direction extending in the front-to-back direction (Y-axis direction) when viewed from above (positive Z-axis direction). The electrostatic input device 10 has a panel 140 provided on its top surface, on which a plurality of operation keys 141 are provided. In this embodiment, the panel 140 has 12 operation keys 141 arranged in a 3-column by 4-row grid pattern.

[0014] Each of the plurality of operation keys 141 can be touched by an operator. The electrostatic input device 10 can detect the touch operation of each of the plurality of operation keys 141 by using a plurality of electrostatic sensor electrodes 111 provided on the insulating substrate 110.

[0015] Each of the operation keys 141 is an example of a “transparent area.” Each of the operation keys 141 is irradiated with light from the LEDs 112 and 113 provided on the insulating substrate 110 via the light guide plate 130, and can emit light individually by transmitting the light.

[0016] In addition, on panel 140, the area where the multiple operation keys 141 are located is a translucent area that transmits light from below (the negative side of the Z axis), and the area other than the multiple operation keys 141 is a light-shielding area 142 that does not transmit light from below (the negative side of the Z axis).

[0017] (Configuration of electrostatic input device 10) Fig. 2 is an exploded perspective view of the electrostatic input device 10 according to an embodiment. Fig. 3 is a plan view of an insulating substrate 110 included in the electrostatic input device 10 according to an embodiment. Fig. 4 is a plan view of a light guide plate 130 included in the electrostatic input device 10 according to an embodiment.

[0018] 2, the electrostatic input device 10 includes, in order from the bottom side (negative side of the Z axis) in the figure, an insulating substrate 110, a first adhesive 121, a light guide plate 130, a second adhesive 122, and a panel 140. The electrostatic input device 10 has a layered structure in which these components are stacked one on top of another.

[0019] The insulating substrate 110, the first adhesive 121, the light guide plate 130, the second adhesive 122, and the panel 140 all have a rectangular shape with the longitudinal direction extending in the front-to-back direction (Y-axis direction) when viewed in a plan view from above (positive Z-axis direction).

[0020] The insulating substrate 110 is a flat resin member on which an electronic circuit is constructed. As shown in FIG. 3 , a plurality of electrostatic sensor electrodes 111 corresponding to a plurality of operation keys 141 are provided on the upper surface 110A of the insulating substrate 110. That is, in this embodiment, 12 electrostatic sensor electrodes 111 are provided on the upper surface 110A of the insulating substrate 110, arranged in a 3-column by 4-row grid pattern. Each electrostatic sensor electrode 111 is formed of a thin metal film. Each electrostatic sensor electrode 111 has a substantially square shape when viewed from above (positive direction of the Z axis). More precisely, each electrostatic sensor electrode 111 has a shape (a substantially octagonal shape) in which each of the four corners of the square shape is cut diagonally.

[0021] Each electrostatic sensor electrode 111 can detect a proximity operation by capacitively coupling with the operator's finger when the operator's finger moves in proximity to a corresponding operation key 141 (i.e., stacked on top of it).

[0022] 3 , a first LED 112 and a second LED 113 are mounted on the upper surface 110A of the insulating substrate 110 for each of the multiple electrostatic sensor electrodes 111. Specifically, the first LED 112 is provided at a position facing the front left corner of the electrostatic sensor electrode 111. The second LED 113 is provided at a position facing the rear right corner of the electrostatic sensor electrode 111. In other words, the two LEDs 112 and 113 are provided opposite each other on an extension of the diagonal of the electrostatic sensor electrode 111. Each of the two LEDs 112 and 113 is arranged so that its optical axis faces the center of the electrostatic sensor electrode 111.

[0023] The light guide plate 130 is provided on the upper side of the insulating substrate 110 so as to cover all of the electrostatic sensor electrodes 111. The light guide plate 130 is a flat plate-shaped member made of a light-transmitting material (e.g., a resin material, a glass material, etc.). The light guide plate 130 guides light emitted from the plurality of LEDs 112, 113 provided in light source through holes 132 of the light guide plate 130 to each of the plurality of operation keys 141 provided on the upper side (positive side of the Z axis) of the light guide plate 130, thereby causing each of the plurality of operation keys 141 to emit light.

[0024] As shown in FIG. 4 , the light guide plate 130 has a plurality of illumination areas 131 corresponding to a plurality of operation keys 141. That is, in this embodiment, the light guide plate 130 has 12 illumination areas 131 arranged in a 3-column by 4-row grid. Each of the illumination areas 131 is an area overlapping the lower side (negative side of the Z axis) of a corresponding one of the operation keys 141 and has the same shape (i.e., a substantially square shape) as the corresponding one of the operation keys 141. Furthermore, each of the illumination areas 131 is provided overlapping the upper side (positive side of the Z axis) of a corresponding one of the electrostatic sensor electrodes 111. As a result, each of the illumination areas 131 guides light emitted by the corresponding LEDs 112, 113 to the corresponding one of the operation keys 141, causing the corresponding one of the operation keys 141 to individually emit light.

[0025] 4 , the light guide plate 130 is provided with a light source through hole 132 and a light-shielding through hole 133 for each of the plurality of illumination regions 131. The light source through hole 132 is provided at a position facing the left front corner of the illumination region 131. The light-shielding through hole 133 is provided at a position facing the right rear corner of the illumination region 131.

[0026] The panel 140 is a flat member made of a light-transmitting material (e.g., a resin material, a glass material, etc.). As shown in FIG. 1 , the panel 140 has 12 operation keys 141 arranged in a 3-column by 4-row grid. Each of the operation keys 141 has a substantially square shape when viewed from above (the positive direction of the Z axis). Each of the operation keys 141 emits light by transmitting light from below (the negative side of the Z axis). As shown in FIG. 1 , the panel 140 has a light-shielding region 142 that does not transmit light from below (the negative side of the Z axis) in a portion other than the operation keys 141. For example, the light-shielding region 142 is formed by printing a light-shielding layer using ink with light-shielding properties.

[0027] Each of the plurality of operation keys 141 is provided on top of a corresponding one of the electrostatic sensor electrodes 111 via the light guide plate 130. This allows each of the plurality of operation keys 141 to detect a proximity operation on that operation key 141 by means of the corresponding one of the electrostatic sensor electrodes 111. This also allows each of the plurality of operation keys 141 to emit light individually by guiding light emitted from the two LEDs 112, 113 toward the corresponding one of the electrostatic sensor electrodes 111 via the light guide plate 130.

[0028] The first adhesive 121 is provided between the light guide plate 130 and the insulating substrate 110. The first adhesive 121 is a double-sided tape in the shape of a rectangular frame that follows the outer periphery of the light guide plate 130. The first adhesive 121 has a square-shaped opening 121A within the rectangular frame, and the opening 121A forms a space having a minute height dimension between the light guide plate 130 and the insulating substrate 110.

[0029] The second adhesive 122 is provided between the light guide plate 130 and the panel 140. The second adhesive 122 is a double-sided tape in the shape of a rectangular frame that follows the outer periphery of the light guide plate 130. The second adhesive 122 has a square-shaped opening 122A within the rectangular frame, and the opening 122A forms a space having a minute height dimension between the light guide plate 130 and the panel 140.

[0030] (Configuration of Light Guide Plate 130) Fig. 5 is a partial enlarged view of the light guide plate 130 shown in Fig. 4. As shown in Fig. 5, the light guide plate 130 has a light source through hole 132 and a light-blocking through hole 133 for each illumination region 131.

[0031] The light source through hole 132 is provided at a position facing a second corner 131B, which is the front left corner of the illumination region 131 (the corner on the negative side of the X axis and the positive side of the Y axis). The light source through hole 132 is also provided at a position overlapping with a light-blocking region 142 of the panel 140. The first LED 112 is disposed within the light source through hole 132. The light source through hole 132 has a shape that extends in a direction tilted at 45° with respect to the X axis and the Y axis when viewed in a plan view from above (the positive direction of the Z axis). It is preferable that the light source through hole 132 be at an angle perpendicular to the diagonal of the illumination region 131.

[0032] The light-shielding through hole 133 is provided at a position facing a first corner 131A, which is the rear right corner of the illumination region 131. The light source through hole 132 is provided at a position overlapping with the light-shielding region 142 of the panel 140. The light-shielding through hole 133 has a bent shape (substantially L-shaped) surrounding the first corner 131A of the illumination region 131 in a plan view from above (positive direction of the Z axis), and is provided separately from the other light source through holes 132.

[0033] Specifically, as shown in FIG. 5 , the light-shielding through hole 133 has a first linear portion 133A, a second linear portion 133B, and a diagonal portion 133C. The first linear portion 133A extends in the left-right direction (X-axis direction) along the rear side (the side on the negative side of the Y-axis) of the illumination region 131. The second linear portion 133B extends in the front-rear direction (Y-axis direction) along the right side (the side on the positive side of the X-axis) of the illumination region 131. The diagonal portion 133C is provided between the first linear portion 133A and the second linear portion 133B, faces the first corner portion 131A of the illumination region 131, and connects the first linear portion 133A and the second linear portion 133B. The diagonal portion 133C extends in a direction tilted 45° with respect to the X-axis and Y-axis in a plan view from above (the positive direction of the Z-axis). The second LED 113 is disposed within the shaded portion 133C. Preferably, the shaded portion 133C is at an angle perpendicular to the diagonal of the illumination area 131. Although it depends on the directivity angle (light distribution angle) of the LED, if the optical axis of the first LED 112 and the shaded portion 133C are perpendicular to each other, the operation key 141 can be illuminated uniformly (i.e., without uneven brightness). Furthermore, it is possible to prevent light from leaking to other operation keys 141.

[0034] In particular, as in the example shown in Figure 5, when the electrostatic sensor electrode 111 and the illumination area 131 are approximately square, it is preferable that the lengths of the first straight portion 133A and the second straight portion 133B of the light-shielding through hole 133 are equal to each other, and that the oblique portion 133C is inclined at 45 degrees with respect to each of the first straight portion 133A and the second straight portion 133B.

[0035] By having the above-described configuration, the light-shielding through hole 133 can surround the right (positive direction of the X-axis), rear (negative direction of the Y-axis), and right-rear diagonal side of the illuminated area 131, and when light is irradiated onto the illuminated area 131, it can suppress leakage of light from the illuminated area 131 to the right (positive direction of the X-axis), rear (negative direction of the Y-axis), and right-rear diagonal side.

[0036] (Arrangement of LEDs 112, 113 on Light Guide Plate 130) FIG. 6 is a plan view of the light guide plate 130 and insulating substrate 110 (overlapping each other) included in the electrostatic input device 10 according to one embodiment.

[0037] As shown in FIG. 6 , by stacking the light guide plate 130 on the insulating substrate 110, the first LED 112 is arranged for each of the plurality of light source through holes 132 of the light guide plate 130 so that its optical axis Ax1 faces the center of the illumination region 131, and the second LED 113 is arranged for each of the plurality of shaded through holes 133C of the light shielding through holes 133 of the light guide plate 130 so that its optical axis Ax2 faces the center of the illumination region 131. When two LEDs 112, 113 are used for each operation key 141, it is preferable to provide LEDs of complementary colors. That is, if one is yellow, the other is preferably blue. If one is cyan (indigo purple), the other is preferably red. If one is magenta (reddish purple), the other is preferably green.

[0038] As a result, in one embodiment of the electrostatic input device 10, by illuminating two LEDs 112, 113 corresponding to one operation key 141, the light irradiated from the two LEDs 112, 113 to one illumination area 131 is emitted from the top surface of the one illumination area 131, and one operation key 141 that is superimposed on the one illumination area 131 can be individually illuminated.

[0039] In this case, the electrostatic input device 10 according to one embodiment can suppress leakage of light to the right (positive direction of the X-axis), rear (negative direction of the Y-axis) and other illuminated areas 131 (i.e., other operation keys 141) located diagonally rearward and to the right of one illuminated area 131 by using the light-shielding through holes 133.

[0040] Therefore, according to one embodiment of the electrostatic input device 10, even if there are three or more rows of illumination areas 131 in the front-to-back direction and three or more rows of illumination areas 131 in the left-to-right direction, a single light guide plate 130 can illuminate each individual illumination area 131, and when one operation key 141 is illuminated, light leakage to other operation keys 141 can be suppressed.

[0041] In particular, in one embodiment of the electrostatic input device 10, the bends of the light-shielding through holes 133 in the light guide plate 130 are at obtuse angles, so that the reduction in strength of the light guide plate 130 due to the provision of multiple light-shielding through holes 133 can be suppressed.

[0042] 6 , in the electrostatic input device 10 according to an embodiment, each of the plurality of second LEDs 113 is provided in a light-shielding through-hole 133 of the light guide plate 130. Therefore, according to the electrostatic input device 10 according to an embodiment, the number of holes formed in the light guide plate 130 can be reduced, and the durability of the light guide plate 130 can be increased.

[0043] 6 , in the electrostatic input device 10 according to the embodiment, the light guide plate 130 has a plurality of light source through holes 132, and a plurality of first LEDs 112 are provided in the light source through holes 132. Therefore, in the electrostatic input device 10 according to the embodiment, the light-shielding through holes 133 are arranged in the irradiation direction of the light from the first LEDs 112 (i.e., on the diagonal), so that most of the light irradiated from the first LEDs 112 and traveling while diffusing can be blocked by the light-shielding through holes 133, and can be prevented from leaking to other illumination areas 131 (i.e., other operation keys 141).

[0044] 4 and 6, the plurality of light source through holes 132 have the same shape, so that the electrostatic input device 10 according to the embodiment can obtain a similar light blocking effect for each of the plurality of illumination areas 131 (i.e., the plurality of operation keys 141) by the plurality of light source through holes 132.

[0045] (Arrangement of LEDs 112, 113 on Light Guide Plate 130) FIG. 7 is a partially enlarged plan view of the light guide plate 130 and insulating substrate 110 (overlapping each other) included in the electrostatic input device 10 according to one embodiment.

[0046] In the electrostatic input device 10 according to one embodiment, each of the plurality of electrostatic sensor electrodes 111 has a square shape with each of the four corners cut diagonally (approximately an octagonal shape), as shown in FIG. 7 .

[0047] 7 , the electrostatic input device 10 according to the embodiment can arrange the first LED 112 adjacent to and facing the first corner 111A, which is the oblique side of the front left corner of the electrostatic sensor electrode 111, and can arrange the second LED 113 adjacent to and facing the second corner 111B, which is the oblique side of the rear right corner of the electrostatic sensor electrode 111. Therefore, the electrostatic input device 10 according to the embodiment can reduce the area of ​​the configuration around the electrostatic sensor electrode 111, including the two LEDs 112 and 113, and therefore can arrange the multiple electrostatic sensor electrodes 111 closer to each other.

[0048] 7 , each of the plurality of electrostatic sensor electrodes 111 has a shape and size that can accommodate the entire illumination area 131, that is, the shape and size that can accommodate the entire operation key 141. As a result, the electrostatic input device 10 according to the embodiment can reliably detect the touch operation of the operation key 141 by the electrostatic sensor electrode 111, regardless of the touch operation position on the operation key 141.

[0049] (First Modification of LED Arrangement) Fig. 8 is a diagram showing a first modification of the arrangement of LEDs in the electrostatic input device 10 according to one embodiment. As shown in Fig. 8, the electrostatic input device 10 according to one embodiment may be configured such that the first LEDs 112 are provided in each of the plurality of light source through holes 132, and the second LEDs 113 are not provided in each of the plurality of light-blocking through holes 133.

[0050] (Second Modification of LED Arrangement) FIG. 9 is a diagram showing a second modification of the arrangement of LEDs in the electrostatic input device 10 according to an embodiment. As shown in FIG. 9 , the electrostatic input device 10 according to an embodiment may be configured such that a first LED 112 is provided in each of the plurality of light source through holes 132, and a plurality of second LEDs 113 are provided in each of the plurality of light-blocking through holes 133. For example, as shown in FIG. 9 , a second LED 113 may be provided in each of the first linear portion 133A and the second linear portion 133B of each of the plurality of light-blocking through holes 133. In this case, as shown in FIG. 9 , it is preferable to arrange each of the two second LEDs 113 so that the optical axis Ax2 faces the center of the illumination area 131. When three LEDs are provided for each operation key 141, it is preferable to use LEDs of the three primary colors of light: red, green, and blue.

[0051] (First Modification of the Configuration of the Light-Shielding Through-Hole 133) FIG. 10 is a diagram showing a first modification of the configuration of the light-shielding through-hole 133 in the electrostatic input device 10 according to an embodiment.

[0052] In one embodiment of the light guide plate 130, for some of the light-shielding through holes 133 that do not have other illumination areas 131 in the direction of light irradiation from the first LED 112, the shape of the light-shielding through holes 133 may be changed, or the light-shielding through holes 133 may not be provided.

[0053] For example, as shown in FIG. 10, each of the illumination areas 131-3, 131-6, and 131-9 provided in the rightmost column of the light guide plate 130 does not have another illumination area 131 on the right side thereof, and therefore, for these illumination areas 131, a light-shielding through hole 133 may be provided that does not have a second straight portion 133B (i.e., "the other straight portion on the side where there is no other adjacent electrostatic sensor electrode") or a diagonal portion 133C for preventing light leakage to the right, but only has a first straight portion 133A (i.e., "the one straight portion on the side where there is another adjacent electrostatic sensor electrode") for preventing light leakage to the rear.

[0054] Furthermore, for example, as shown in FIG. 10, each of the illumination areas 131-10, 131-11 provided in the last row of the light guide plate 130 does not have another illumination area 131 to the rear, and therefore, for these illumination areas 131, a light-shielding through hole 133 may be provided that does not have a first straight portion 133A (i.e., "the other straight portion on the side where there are no other adjacent electrostatic sensor electrodes") or a diagonal portion 133C for preventing light from leaking backward, but only has a second straight portion 133B (i.e., "the one straight portion on the side where there are other adjacent electrostatic sensor electrodes") for preventing light from leaking to the right.

[0055] Also, for example, as shown in Figure 10, the illumination area 131-12 provided in the rightmost column and last row of the light guide plate 130 does not have other illumination areas 131 on the right side or rear side, so it is not necessary to provide a light-shielding through hole 133 for this illumination area 131-12.

[0056] (Second Modification of the Configuration of the Light-Shielding Through-Hole 133) FIG. 11 is a diagram showing a second modification of the configuration of the light-shielding through-hole 133 in the electrostatic input device 10 according to an embodiment.

[0057] In one embodiment of the light guide plate 130, as shown in FIG. 11, multiple light-shielding through holes 133 may be provided for each of the multiple illumination areas 131, each of which has a shape that surrounds the right rear corner of the illumination area 131.

[0058] As a result, the electrostatic input device 10 according to the embodiment can further enhance the effect of suppressing light from leaking to other illumination areas 131 .

[0059] (Third Modification of the Configuration of the Light-Shielding Through-hole 133) FIG. 12 is a diagram showing a third modification of the configuration of the light-shielding through-hole 133 in the electrostatic input device 10 according to an embodiment.

[0060] In the light guide plate 130 according to one embodiment, other light-shielding through holes may be further provided for each of the plurality of illumination regions 131. For example, as shown in Fig. 12, in addition to the light-shielding through hole 133, a light-shielding through hole 134 and a light-shielding through hole 135 may be further provided for each of the plurality of illumination regions 131.

[0061] The light-shielding through hole 134 is an example of a "second light-shielding through hole" and is provided to shield the gap between the other light source through hole 132 and the first straight portion 133A of the light-shielding through hole 133 behind the illumination area 131, thereby preventing light from leaking through the gap into the other illumination area 131 behind.

[0062] The light-shielding through hole 135 is another example of a "second light-shielding through hole" and is provided to the right of the illumination area 131 so as to shield the gap between the other light source through hole 132 and the second straight portion 133B of the light-shielding through hole 133, thereby preventing light from leaking through the gap into the illumination area 131 on the right.

[0063] (Configuration of Light Emission Control System Included in Electrostatic Input Device 10) FIG. 13 is a diagram showing the configuration of a light emission control system included in the electrostatic input device 10 according to one embodiment.

[0064] As shown in FIG. 13, the light emission control system of the electrostatic input device 10 includes a plurality of electrostatic sensor electrodes 111 corresponding to a plurality of operation keys 141, a plurality of first LEDs 112 corresponding to a plurality of operation keys 141, a plurality of second LEDs 113 corresponding to a plurality of operation keys 141, and a control circuit 114.

[0065] The control circuit 114 controls the light emission states of the first LEDs 112 and the second LEDs 113 in accordance with the proximity state of an operating object (an operator's finger) relative to the panel 140, which is detected by the electrostatic sensor electrodes 111. The control circuit 114 is, for example, an integrated circuit (IC) provided on the insulating substrate 110. However, the present invention is not limited to this, and the control circuit 114 may be provided outside the insulating substrate 110.

[0066] The control circuit 114 can individually control the light emission of each of the plurality of operation keys 141. Specifically, the control circuit 114 can individually control the light emission (on, off, brightness, and light emission color) of each of the plurality of operation keys 141 by controlling the light emission of the first LED 112 and the second LED 113 corresponding to that operation key 141.

[0067] The control circuit 114 can identify one of the plurality of operation keys 141 selected by the operator's finger from among the plurality of operation keys 141. For example, the control circuit 114 can identify one of the plurality of operation keys 141 that has a capacitance value equal to or greater than a predetermined threshold and corresponds to one electrostatic sensor electrode 111 with the highest capacitance value from among the plurality of electrostatic sensor electrodes 111, as the one of the plurality of operation keys 141 selected by the operator's finger.

[0068] (First Example of Light Emission Control Method by Control Circuit 114) FIG. 14 is a diagram showing a first example of a light emission control method by the control circuit 114 included in the electrostatic input device 10 according to an embodiment.

[0069] In the example shown in FIG. 14, when the operator's hand is not close to the operation panel, all operation keys are in an unlit state, as shown in FIG. 14(a).

[0070] When the operator's hand approaches the surface of the panel 140 within a predetermined distance (e.g., 60 mm) and is detected by any of the electrostatic sensor electrodes 111, the control circuit 114 lights up all of the operation keys 141 in deep blue, as shown in FIG. 14( b). This allows the electrostatic input device 10 according to one embodiment to easily and visually indicate to the operator that the multiple operation keys 141 are operable. At this time, the control circuit 114 sets the lowest brightness for all of the operation keys 141. Also, at this time, the control circuit 114 sets the luminous color for all of the operation keys 141 to deep blue, as an example.

[0071] Furthermore, when the electrostatic sensor electrode 111 corresponding to one of the operation keys 141 on the panel 140 detects that the fingers of the operator's hand have come within a predetermined first distance (e.g., 45 mm) of that one of the operation keys 141, the control circuit 114 makes the brightness and luminous color of that one of the operation keys 141 different from those of the other operation keys 141, as shown in Figure 14 (c), so that the operator can visually understand that that one of the operation keys 141 has been selected.

[0072] In particular, the control circuit 114 sets the brightness of each operation key 141 so that the brightness of the selected operation key 141 is the highest and the brightness gradually decreases as the distance from the selected operation key 141 increases, as shown in Figure 14 (c), thereby allowing the operator to visually grasp the selected operation key 141.

[0073] For example, in the example shown in FIG. 14( c), a white light emission color with the highest brightness and the lowest saturation is set to the selected operation key "2" (meaning the operation key 141 marked "2". The same applies to the other operation keys 141 hereinafter). A light emission color with the second highest brightness and slightly low saturation, light blue, is set to the operation keys "1", "3", and "5" adjacent to the operation key "2" in the front, rear, left, and right directions. A blue light emission color with the third highest brightness and high saturation is set to the operation keys "4" and "6", which are adjacent to the operation key "2" in the diagonal direction. A deep blue light emission color with the lowest brightness and highest saturation, similar to FIG. 14( b), is set to the other keys not adjacent to the operation key "2".

[0074] That is, the control circuit 114 controls the light emission of the plurality of LEDs 112, 113 so that the brightness of the other operation keys 141 adjacent to one operation key 141 approached by the operating body among the plurality of operation keys 141 is higher than the brightness of the other operation keys 141 that are not adjacent to the one operation key approached by the operating body. As a result, the electrostatic input device 10 according to an embodiment allows the operator to intuitively and easily grasp which operation key 141 has been selected based on the change in brightness of the other operation keys 141 around the selected operation key 141. Therefore, the electrostatic input device 10 according to an embodiment allows the operator to visually and easily grasp which operation key 141 has been selected among the plurality of operation keys 141.

[0075] Furthermore, the control circuit 114 controls the light emission of the plurality of LEDs 112, 113 so that the brightness of the other operation keys 141 adjacent in the front, rear, left, and right directions to the one operation key 141 close to the operating body is higher than the brightness of the other operation keys 141 adjacent in the diagonal direction to the one operation key 141 close to the operating body. As a result, the electrostatic input device 10 according to an embodiment can intuitively and easily grasp which operation key 141 has been selected based on the change in brightness of the other operation keys 141 around the selected one operation key 141. Therefore, the electrostatic input device 10 according to an embodiment can visually and easily grasp which operation key 141 has been selected among the plurality of operation keys 141.

[0076] Furthermore, the control circuit 114 controls the light emission of the plurality of LEDs 112, 113 so that the brightness of one operation key 141 that the operating body is close to is higher than the brightness of the other operation keys 141 adjacent to that one operation key 141. As a result, in the electrostatic input device 10 according to one embodiment, the selected operation key 141 emits the brightest light, allowing the operator to visually easily know which of the plurality of operation keys 141 has been selected.

[0077] Subsequently, when the electrostatic sensor electrode 111 corresponding to the selected operation key 141 detects that the fingers of the operator's hand have come within a predetermined second distance (e.g., 30 mm) of the selected operation key 141, the control circuit 114 causes the operation key 141 to blink for a predetermined period of time, as shown in Figure 14 (d), thereby allowing the operator to visually understand that the selection of the operation key 141 is continuing.

[0078] Furthermore, when the state in which the fingers of the operator's hand are within a predetermined third distance (e.g., 30 mm) of the selected one of the operation keys 141 has elapsed for a predetermined time, the control circuit 114 lights up the selected one of the operation keys 141 at the highest brightness similar to that in FIG. 14(c) but in a different light color (e.g., yellow) from that in FIG. 14(c), as shown in FIG. 14(e), thereby allowing the operator to visually understand that the selection of the selected one of the operation keys 141 has been confirmed.

[0079] That is, when the distance from the operator's fingers to the panel 140 becomes less than a first threshold, the control circuit 114 controls the light emission of the plurality of LEDs so that the luminance of the selected operation key 141 becomes higher than the luminance of the other operation keys adjacent to the selected operation key, and when the distance from the operator's fingers to the panel 140 becomes less than a second threshold that is smaller than the first threshold, the control circuit 114 confirms the selection of the selected operation key 141 and changes the luminous color of the selected operation key 141. In this way, the electrostatic input device 10 according to one embodiment changes the luminous color of the operation key 141 whose selection has been confirmed, allowing the operator to visually easily grasp which of the plurality of operation keys 141 has been confirmed.

[0080] (Second Example of Light Emission Control Method by Control Circuit 114) FIG. 15 is a diagram showing a second example of a light emission control method by the control circuit 114 included in the electrostatic input device 10 according to an embodiment.

[0081] In the example shown in FIG. 15, when the operator's hand is not close to the operation panel, all operation keys are in an unlit state, as shown in FIG. 15(a).

[0082] When the operator's hand approaches within a predetermined distance (e.g., 50 mm) from the surface of the panel 140 and the operator's hand is detected by any of the electrostatic sensor electrodes 111, the control circuit 114 lights up all of the operation keys 141, as shown in Fig. 15(b) . At this time, the control circuit 114 sets the lowest brightness for all of the operation keys 141. Also, at this time, the control circuit 114 sets the luminous color for all of the operation keys 141 to indigo blue, as an example.

[0083] Furthermore, when the electrostatic sensor electrode 111 corresponding to one of the operation keys 141 on the panel 140 detects that the fingers of the operator's hand have come within a predetermined first distance (e.g., 20 to 50 mm) of that one of the operation keys 141, the control circuit 114 makes the brightness and luminous color of that one of the operation keys 141 different from those of the other operation keys 141, as shown in Figure 15 (c), thereby allowing the operator to visually understand that that one of the operation keys 141 has been selected.

[0084] In particular, the control circuit 114 sets the brightness of each operation key 141 so that the brightness of the selected operation key 141 is the highest and the brightness gradually decreases as the distance from the selected operation key 141 increases, as shown in Figure 15 (c), thereby allowing the operator to visually grasp the selected operation key 141.

[0085] For example, in the example shown in Fig. 15(c), the highest brightness (e.g., 100%) and white light emission color are set for the selected operation key "5", and the second highest brightness (e.g., 30%) and blue light emission color are set for the operation keys "2", "4", "6", and "8" adjacent to the operation key "5" in the front, rear, left, and right directions. The other keys are set to the lowest brightness and indigo blue as in Fig. 15(b).

[0086] Subsequently, when the electrostatic sensor electrode 111 corresponding to the selected operation key 141 detects that the operator's finger has come within a predetermined second distance (e.g., 20 mm) of the selected operation key 141, the control circuit 114 causes the operation keys 141 adjacent to the selected operation key 141 in the front-rear and left-right directions to emit light at the same brightness and in the same color as the selected operation key 141, as shown in FIG. 15( d ). For example, in the example shown in FIG. 15( d ), the operation keys "2," "4," "6," and "8," which are adjacent to the selected operation key "5" in the front-rear and left-right directions, emit light at the same brightness (e.g., 100%) and in the same color (white) as the selected operation key "5." This allows the operator to visually understand that the selection of the selected operation key 141 is continuing.

[0087] Furthermore, when the state in which the fingers of the operator's hand are within a predetermined second distance (e.g., 20 mm) from the selected one of the operation keys 141 has elapsed for a predetermined time (e.g., 0.3 seconds), the control circuit 114 lights up the one of the operation keys 141 at the highest brightness (e.g., 100%) similar to that in FIG. 15(c) but in a different light color (e.g., yellow) from that in FIG. 15(c), as shown in FIG. 15(e), thereby allowing the operator to visually understand that the selection of the one of the operation keys 141 has been confirmed.

[0088] When the electrostatic sensor electrode 111 corresponding to a selected operation key 141 detects that the operator's fingers have touched the selected operation key 141, the control circuit 114 can immediately transition the lighting state of each operation key 141 to the state shown in Figure 15 (e).

[0089] (Third Example of Light Emission Control Method by Control Circuit 114) FIG. 16 is a diagram showing a third example of a light emission control method by the control circuit 114 included in the electrostatic input device 10 according to an embodiment.

[0090] In the example shown in FIG. 16, when the operator's hand is not close to the operation panel, all operation keys are in an unlit state, as shown in FIG. 16(a).

[0091] When the operator's hand approaches within a predetermined distance (e.g., 60 mm) from the surface of the panel 140 and the operator's hand is detected by any of the electrostatic sensor electrodes 111, the control circuit 114 lights up all of the operation keys 141 as shown in Fig. 16(b). At this time, the control circuit 114 sets the lowest brightness for all of the operation keys 141. Also, at this time, the control circuit 114 sets the luminous color for all of the operation keys 141 to indigo blue, as an example.

[0092] Furthermore, when the electrostatic sensor electrode 111 corresponding to one of the operation keys 141 on the panel 140 detects that the fingers of the operator's hand have come within a predetermined first distance (e.g., 45 mm) of that one of the operation keys 141, the control circuit 114 makes the brightness and luminous color of that one of the operation keys 141 different from those of the other operation keys 141, as shown in Figure 16 (c), so that the operator can visually understand that that one of the operation keys 141 has been selected.

[0093] In particular, the control circuit 114 sets the brightness of each operation key 141 so that the brightness of the selected operation key 141 is the highest and the brightness gradually decreases as the distance from the selected operation key 141 increases, as shown in Figure 16 (c), thereby allowing the operator to visually grasp the selected operation key 141.

[0094] For example, in the example shown in FIG. 16( c), the highest brightness and white light emission color are set to the selected operation key "2" (meaning the operation key 141 marked "2". The same applies to the other operation keys 141 hereinafter). The second highest brightness is set to the operation keys "1", "3", and "5" adjacent to the operation key "2" in the front, rear, left, and right directions. The third highest brightness is set to the operation keys "4" and "6" diagonally adjacent to the operation key "2". The other keys not adjacent to the operation key "2" are set to the lowest brightness similar to that in FIG. 16( b).

[0095] Subsequently, while the fingers of the operator's hand continue to be close to the selected operation key 141 within a predetermined second distance (for example, 30 mm), the control circuit 114 gradually decreases the brightness of the operation keys 141 adjacent to the selected operation key 141 (in the example shown in FIG. 16(d), operation key "1", operation key "3", operation key "4", operation key "5", and operation key "6") according to the distance from the operator's fingers, as shown in FIG. 16(d), thereby allowing the operator to visually understand that the selection of the selected operation key 141 continues.

[0096] Furthermore, when a state in which the fingers of the operator's hand are in proximity to the selected operation key 141 within a predetermined second distance (e.g., 30 mm) has elapsed for a predetermined time, the control circuit 114 lights up the selected operation key 141 at the highest brightness similar to that in FIG. 16(c) but in a different light color (e.g., yellow) from that in FIG. 16(c), as shown in FIG. 16(e), and also lights up the operation keys 141 adjacent to the selected operation key 141 (in the example shown in FIG. 16(d), the operation keys 141 (operation key "1", operation key "3", operation key "4", operation key "5", and operation key "6")) to the same brightness as that in FIG. 16(b) or to a brightness even lower than that in FIG. 16(b), thereby allowing the operator to visually understand that the selection of the selected operation key 141 has been confirmed.

[0097] (Fourth Example of Light Emission Control Method by Control Circuit 114) FIG. 17 is a diagram showing a fourth example of a light emission control method by the control circuit 114 included in the electrostatic input device 10 according to an embodiment.

[0098] In the example shown in FIG. 17, when the operator's hand is not close to the operation panel, all operation keys are in an unlit state, as shown in FIG. 17(a).

[0099] When the operator's hand approaches within a predetermined distance (e.g., 60 mm) from the surface of the panel 140 and is detected by any of the electrostatic sensor electrodes 111, the control circuit 114 lights up all of the operation keys 141, as shown in Fig. 17(b). At this time, the control circuit 114 sets a relatively low predetermined brightness for all of the operation keys 141. Also, at this time, the control circuit 114 sets the luminous color for all of the operation keys 141 to indigo blue, as an example.

[0100] Furthermore, when the electrostatic sensor electrode 111 corresponding to one of the operation keys 141 on the panel 140 detects that the fingers of the operator have come within a predetermined first distance (e.g., 45 mm) of that one of the operation keys 141, the control circuit 114 makes the brightness and luminous color of that one of the operation keys 141 different from those of the other operation keys 141, as shown in Figure 17 (c), so that the operator can visually understand that that one of the operation keys 141 has been selected.

[0101] In particular, the control circuit 114 sets the brightness of each operation key 141 so that the brightness of the selected operation key 141 is the highest and the brightness gradually decreases as the distance from the selected operation key 141 increases, as shown in Figure 17 (c), thereby allowing the operator to visually grasp the selected operation key 141.

[0102] For example, in the example shown in FIG. 17( c), the highest brightness and white light emission color are set to the selected operation key "2" (meaning the operation key 141 marked "2". The same applies to the other operation keys 141 hereinafter). The second highest brightness is set to the operation keys "1", "3", and "5" adjacent to the operation key "2" in the front, rear, left, and right directions. The third highest brightness is set to the operation keys "4" and "6" diagonally adjacent to the operation key "2". The lowest brightness is set to the other keys not adjacent to the operation key "2".

[0103] Subsequently, while the fingers of the operator's hand continue to be close to the selected operation key 141 within a predetermined second distance (e.g., 30 mm), the control circuit 114 keeps the brightness of the selected operation key 141 constant, as shown in Figure 17 (d), and gradually decreases the brightness of all operation keys 141 other than the selected operation key 141, thereby allowing the operator to visually understand that the selection of the selected operation key 141 is continuing.

[0104] Furthermore, when the state in which the fingers of the operator's hand are within a predetermined second distance (e.g., 30 mm) of the selected operation key 141 has elapsed for a predetermined time, the control circuit 114 lights up the selected operation key 141 at the highest brightness as in FIG. 17(c) but in a different light color (e.g., yellow) from that in FIG. 17(c), as shown in FIG. 17(e), and sets the brightness of all operation keys 141 other than the selected operation key 141 to the lowest brightness, thereby allowing the operator to visually understand that the selection of the selected operation key 141 has been confirmed.

[0105] (Fifth Example of Light Emission Control Method by Control Circuit 114) FIG. 18 is a diagram showing a fifth example of a light emission control method by the control circuit 114 included in the electrostatic input device 10 according to an embodiment.

[0106] In the example shown in FIG. 18, when the operator's hand is not close to the operation panel, all operation keys are in an unlit state, as shown in FIG. 18(a).

[0107] When the operator's hand approaches within a predetermined distance (e.g., 60 mm) from the surface of the panel 140 and is detected by any of the electrostatic sensor electrodes 111, the control circuit 114 lights up all of the operation keys 141, as shown in Fig. 18(b). At this time, the control circuit 114 sets a relatively low predetermined brightness for all of the operation keys 141. Also, at this time, the control circuit 114 sets the luminous color for all of the operation keys 141 to indigo blue, as an example.

[0108] Furthermore, when the electrostatic sensor electrode 111 corresponding to one of the operation keys 141 on the panel 140 detects that the fingers of the operator's hand have come within a predetermined second distance (e.g., 45 mm) of that one of the operation keys 141, the control circuit 114 makes the brightness and luminous color of that one of the operation keys 141 different from those of the other operation keys 141, as shown in Figure 18 (c), so that the operator can visually understand that that one of the operation keys 141 has been selected.

[0109] In particular, the control circuit 114 sets the brightness of each operation key 141 so that the brightness of the selected operation key 141 is the highest and the brightness gradually decreases as the distance from the selected operation key 141 increases, as shown in Figure 18 (c), thereby allowing the operator to visually grasp the selected operation key 141.

[0110] For example, in the example shown in FIG. 18( c), the highest brightness and white light emission color are set to the selected operation key "2" (meaning the operation key 141 marked "2". The same applies to the other operation keys 141 hereinafter). The second highest brightness is set to the operation keys "1", "3", and "5" adjacent to the operation key "2" in the front, rear, left, and right directions. The third highest brightness is set to the operation keys "4" and "6" diagonally adjacent to the operation key "2". The lowest brightness is set to the other keys not adjacent to the operation key "2".

[0111] Next, when the elapsed time during which the fingers of the operator's hand are within a predetermined second distance (e.g., 30 mm) from the selected operation key 141 reaches a first elapsed time, the control circuit 114 causes the other operation keys 141 (operation key "4" and operation key "6") diagonally adjacent to the selected operation key 141 to flash once while changing the luminous color in a gradation from blue to yellow, as shown in Figures 18(d) and 18(e), thereby allowing the operator to visually understand that the selection of the selected operation key 141 is continuing.

[0112] Furthermore, when the elapsed time during which the fingers of the operator's hand are within a predetermined second distance (for example, 30 mm) from the selected operation key 141 reaches a second elapsed time that is slightly longer than the first elapsed time, the control circuit 114 causes the other operation keys 141 (operation key "1", operation key "3", operation key "5") adjacent to the selected operation key 141 in the front-rear and left-right directions to flash once while changing the luminous color gradually from blue to yellow, as shown in Figures 18(f) and 18(g), thereby allowing the operator to visually understand that the selection of the selected operation key 141 is continuing.

[0113] Finally, as shown in FIG. 18(g), the control circuit 114 lights up the selected operation key 141 at the highest brightness (e.g., 100%) similar to that in FIG. 18(c) but in a different light color (e.g., yellow) from that in FIG. 18(c), and turns off the other operation keys 141 adjacent to the selected operation key 141, thereby allowing the operator to visually understand that the selection of the selected operation key 141 has been confirmed.

[0114] Furthermore, when the state in which the fingers of the operator's hand are within a predetermined second distance (e.g., 30 mm) of the selected operation key 141 has elapsed for a predetermined time, the control circuit 114 lights up the selected operation key 141 at the highest brightness as in FIG. 18(c) but in a different light color (e.g., yellow) from that in FIG. 18(c), as shown in FIG. 18(e), and sets the brightness of all operation keys 141 other than the selected operation key 141 to the lowest brightness, thereby allowing the operator to visually understand that the selection of the selected operation key 141 has been confirmed.

[0115] In the examples shown in Figures 13 to 18, after one operation key 141 is selected, when the selection of the one operation key 141 is confirmed, the luminous color of the one operation key 141 is switched from a first luminous color (e.g., white) to a second luminous color (e.g., yellow), but the luminous color of the one operation key 141 may be changed by other methods.

[0116] For example, the control circuit 114 may be configured to discretely change the luminous color of one operation key 141 from a first luminous color (e.g., white) to a second luminous color (e.g., blue) depending on the distance from the operator's finger to the panel 140, from when one operation key 141 is selected until the selection of that operation key 141 is confirmed.

[0117] Furthermore, for example, the control circuit 114 may be configured to change the luminous color of one operation key 141 in a gradation from a first luminous color (e.g., white) to a second luminous color (e.g., blue) depending on the distance from the operator's finger to the panel 140 during the period from when one operation key 141 is selected until the selection of that operation key 141 is confirmed.

[0118] Furthermore, for example, the control circuit 114 may change the luminous color of one operation key 141 in a gradation from a first luminous color (e.g., white) to a second luminous color (e.g., blue) according to the distance from the operator's finger to the panel 140 during the period from when one operation key 141 is selected until the selection of that operation key 141 is confirmed, and may further change the luminous color in a gradation from the second luminous color to a third luminous color (e.g., yellow).

[0119] Furthermore, for example, after one operation key 141 is selected, when the selection of the operation key 141 is confirmed, the control circuit 114 may turn off the light of the operation key 141 and then light it up in the second emission color (e.g., yellow) after the change. In this way, the electrostatic input device 10 according to the embodiment allows the operator to easily visually understand that the selection of the operation key 141 has been confirmed.

[0120] Alternatively, the light emission color of the operation key 141 may be changed by, for example, using the first LED 112 and the second LED 113 that emit different colors, and the control circuit 114 controlling the light intensity of the first LED 112 and the light intensity of the second LED 113. In this case, for example, the first LED 112 and the second LED 113 may be complementary colors (e.g., blue and yellow). In this way, the electrostatic input device 10 according to one embodiment can express a variety of light emission colors of the operation key 141 by the first LED 112 and the second LED 113.

[0121] In this case, the control circuit 114 may control the other operation keys that are not adjacent to the selected operation key so that the saturation is the highest and the luminance is the lowest. Specifically, for the other operation keys that are not adjacent to the selected operation key, only one of the first LED 112 and the second LED 113 is illuminated, thereby making it possible to make the saturation the highest and the luminance the lowest.

[0122] In addition, as an example, the initial (non-selected) luminous color of all the operation keys 141 is indigo blue, but this is not limiting. For example, the initial luminous color of some operation keys 141 (for example, the "C" key and the "E" key other than the numeric keys) may be other than indigo blue (for example, red, green, etc.).

[0123] Although one embodiment of the present invention has been described in detail above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention described in the claims.

[0124] This international application claims priority based on Japanese Patent Application No. 2024-106976, filed on July 2, 2024, the entire contents of which are incorporated herein by reference.

[0125] 10 Capacitive input device 110 Insulating substrate 110A Upper surface 111 Capacitive sensor electrode 111A First corner 111B Second corner 112 First LED 113 Second LED 114 Control circuit 121 First adhesive 121A Opening 122 Second adhesive 122A Opening 130 Light guide plate 131 Illumination area 131A First corner 131B Second corner 132 Light source through hole 133 Light-shielding through hole 133A First linear portion 133B Second linear portion 133C Shaded portion 134 Light-shielding through hole (second light-shielding through hole) 135 Light-shielding through hole (second light-shielding through hole) 140 Panel 141 Operation key (transparent area) 142 Light shielding area Ax1, Ax2 Optical axis

Claims

1. An electrostatic input device comprising: an insulating substrate; a plurality of electrostatic sensor electrodes arranged in a grid pattern on said insulating substrate; a plurality of LEDs mounted on said insulating substrate for each of said electrostatic sensor electrodes; a light guide plate arranged overlaid on said insulating substrate; and a panel arranged overlaid on said light guide plate, said panel having a plurality of transparent regions facing each of said electrostatic sensor electrodes and a light-shielding region arranged in an area other than said transparent regions, wherein said light guide plate has a plurality of light-shielding through holes formed therein, each of said light-shielding through holes being arranged at a position overlapping with said light-shielding region of said panel, having a bent shape in a plan view that surrounds a first corner of said electrostatic sensor electrode, and being arranged separately from other light-shielding through holes.

2. The electrostatic input device according to claim 1, wherein the plurality of light-shielding through holes have the same shape.

3. The electrostatic input device according to claim 1, wherein some of the LEDs are provided inside the light-shielding through-hole.

4. The electrostatic input device according to claim 1, characterized in that the light guide plate has a light source through hole provided at a position facing a second corner of the electrostatic sensor electrode that is diagonally opposite the first corner in a plan view, and some of the plurality of LEDs are provided within the light source through hole.

5. The electrostatic input device according to claim 1, characterized in that each of the plurality of light-shielding through holes has two straight line sections along the two sides forming the first corner of the electrostatic sensor electrode in a plan view, and a diagonal line section provided between the two straight line sections and facing the first corner of the electrostatic sensor electrode.

6. The electrostatic input device according to claim 5, wherein each of the plurality of electrostatic sensor electrodes has a substantially square shape, and each of the plurality of light-shielding through-holes has two straight portions whose lengths are equal to each other, and the oblique portion whose angle is inclined at 45° with respect to each of the two straight portions.

7. The electrostatic input device according to claim 5, wherein each of the plurality of electrostatic sensor electrodes has a square shape with each of the four corners cut diagonally.

8. The electrostatic input device according to claim 5, characterized in that some of the plurality of light-shielding through holes have one of the two straight line portions on a side where another adjacent electrostatic sensor electrode is present, and do not have the other straight line portion on a side where another adjacent electrostatic sensor electrode is not present.

9. The electrostatic input device according to claim 1, wherein the light-shielding through holes are provided in multiple numbers for each of the plurality of electrostatic sensor electrodes.

10. The electrostatic input device according to claim 1, further comprising a second light-shielding through-hole for shielding a gap between the light-shielding through-hole and the LED provided for another adjacent electrostatic sensor electrode for each of the plurality of electrostatic sensor electrodes.

11. An electrostatic input device comprising: an insulating substrate; a plurality of electrostatic sensor electrodes arranged in a grid pattern on the insulating substrate; a plurality of LEDs mounted on the insulating substrate for each of the electrostatic sensor electrodes; a light guide plate arranged overlaid on the insulating substrate; a panel having a plurality of operation keys arranged overlaid on the light guide plate and facing each of the plurality of electrostatic sensor electrodes; and a control circuit for controlling the emission of the plurality of LEDs, wherein the control circuit identifies one of the plurality of operation keys to which an operating body is close based on the capacitance value of each of the plurality of electrostatic sensor electrodes, and controls the emission of the plurality of LEDs so that the brightness of other operation keys adjacent to the identified one operation key is higher than the brightness of other operation keys not adjacent to the identified one operation key.

12. The electrostatic input device according to claim 11, characterized in that the control circuit controls the light emission of the plurality of LEDs so that the brightness of other operation keys adjacent to the one operation key in the front, rear, left, and right directions is higher than the brightness of other operation keys adjacent to the one operation key in the diagonal direction.

13. The electrostatic input device according to claim 12, wherein each of the electrostatic sensor electrodes has a first LED and a second LED that are complementary in color to each other.

14. The electrostatic input device according to claim 13, wherein the other operation keys not adjacent to the one operation key have the highest saturation and the lowest luminance.

15. The electrostatic input device according to any one of claims 11 to 14, characterized in that the control circuit controls the light emission of the plurality of LEDs so that the brightness of the one operation key is higher than the brightness of other operation keys adjacent to the one operation key.

16. The electrostatic input device according to claim 15, wherein the control circuit calculates the distance between the one operation key and the operating body based on the capacitance value of the electrostatic sensor electrode corresponding to the one operation key, controls the light emission of the plurality of LEDs so that the brightness of the one operation key is higher than the brightness of other operation keys adjacent to the one operation key when the distance is less than a first threshold, and confirms the selection of the one operation key and changes the light emission color of the one operation key when the distance is less than a second threshold that is smaller than the first threshold.

17. The electrostatic input device according to claim 16, characterized in that the control circuit controls the illumination of the plurality of LEDs so that all of the plurality of operation keys are turned off when the proximity of the operating object to the panel is not detected, and all of the plurality of operation keys are turned on when the proximity of the operating object to the panel is detected.

18. The electrostatic input device according to claim 17, characterized in that the control circuit, when the distance becomes less than the second threshold value, confirms the selection of the one operation key, turns off the light of the one operation key, and then lights up the one operation key in the changed light color.

19. The electrostatic input device according to claim 18, characterized in that the control circuit keeps the brightness of the one operation key constant while gradually decreasing the brightness of the other operation keys other than the one operation key while the distance is between less than the first threshold value and less than the second threshold value.

20. The electrostatic input device according to claim 19, characterized in that the control circuit changes the luminance at different timings for the other operation keys diagonally adjacent to the one operation key and the other operation keys diagonally adjacent to the one operation key in the front-rear and left-right directions, while the distance is between less than the first threshold value and less than the second threshold value.

21. The electrostatic input device according to claim 20, characterized in that the control circuit discretely changes the luminous color of the one operation key from a first luminous color to a second luminous color according to the distance until the distance becomes less than a second threshold value that is smaller than the first threshold value.

22. The electrostatic input device according to claim 20, characterized in that the control circuit gradually changes the luminous color of the one operation key from a first luminous color to a second luminous color according to the distance until the distance becomes less than a second threshold value that is smaller than the first threshold value.

23. The electrostatic input device according to claim 20, characterized in that the control circuit changes the luminous color of the one operation key in a gradation to a plurality of luminous colors according to the distance until the distance becomes less than a second threshold value that is smaller than the first threshold value.

24. The electrostatic input device according to claim 23, characterized in that the control circuit makes the initial luminous color of some of the operation keys, among the plurality of operation keys, different from the initial luminous color of the other operation keys.

Images