Optical receiving device and optical touch panel device provided with same

A light-receiving device 10 includes a plurality of light-receiving units 10A, 10B, and 10C, in which, in the element substrate 11A constituting the light-receiving unit 10A, the rear surface of a second terminal forming area 16Ac, upon which a connection pad PAc is formed, is bonded to the front surface of a cover glass 14B covering a plurality of light-receiving elements 12 constituting the light-receiving unit 10B, and in the element substrate 11C constituting the light-receiving unit 10C, the rear surface of a first terminal forming area 16Cb, upon which a connection pad PCb is formed, is bonded with the front surface of the cover glass 14B of the light-receiving unit 10B. As a result, an increase in manufacturing cost and a decrease in yield are mitigated so that it is possible to provide a light-receiving device upon which light-receiving elements are disposed continuously over a long distance at a high density, as well as an optical touch panel device provided with the same.

TECHNICAL FIELD

The present invention relates to a light-receiving device that constitutes an optical touch panel device that detects an input position by detecting light, and an optical touch panel device provided with same.

BACKGROUND ART

Touch panels for large panels are currently being developed. For example, in the case of a touch panel for a large panel of approximately 65 inches, an optical touch panel is the main type used. Such an optical touch panel is disclosed in Patent Document 1 and Patent Document 2, for example.

FIG. 12is a drawing that shows a configuration of an optical touch panel of Patent Document 1.

As shown inFIG. 12, an optical touch panel200has a light-emitting device210, and a light-receiving device220. The light-emitting device210has light-emitting elements211, a substrate212, and a lens L201. The light-emitting elements211are disposed in the periphery of a display surface231of a display device230, and are constituted of LEDs or the like. The light-emitting elements211are installed on the substrate212substantially along one line.

The lens L201for the light-emitting elements causes infrared light outputted from the light-emitting elements211to converge, and is provided between the light-emitting elements211and the display surface231. The light-receiving device220has a lens L202for light-receiving elements, light-receiving elements221, and a substrate222. The light-receiving elements221are disposed in the periphery of the display surface231of the display device230, and are constituted of phototransistors or the like.

The light-receiving elements221are in the periphery of the display surface231of the display device230, and are disposed facing the light-emitting elements211through a space232in the vicinity of (above or below) the display surface231of the display device230. The light-emitting elements211output light, which passes through the lens L201, and the light-receiving elements221receive the light.

The infrared light emitted by the light-emitting elements211is caused to converge and is amplified by the lens L201, and then reaches the light-receiving elements221(phototransistors), which are placed far from the light-emitting elements211. After the lens L202causes the infrared light to converge again, the infrared light reaches the light-receiving surfaces of the light-receiving elements221.

By providing the optical touch panel200with lenses L201and L202as stated above, a decrease in resolution of the optical touch panel is prevented.

FIG. 13(a) is a perspective view that shows a configuration of an optical touch panel according to Patent Document 2.FIG. 13(b) is a cross-sectional view ofFIG. 13(a).

As shown inFIG. 13(a), the optical touch panel of Patent Document 2 is formed integrally with an electro-optical device300that has an image display function, and has a coordinate input function on the display surface thereof.

In the center of the electro-optical device300, a coordinate input region302, which is a display surface that displays images and that functions as a touch panel surface, is formed.

Light sources310and light-emitting side reflective plates350are disposed in light-emitting side periphery regions303, which are in the vicinity of the coordinate input region302. Light detectors320and light-receiving side reflective plates360are disposed in light-receiving side periphery regions304, which are in the vicinity of the coordinate input region302. The light detectors320are provided with a plurality of light-receiving elements, and are formed on an element substrate.

When the light emitted from the light source310reaches the light-emitting side reflective plate350, the light-emitting side reflective plate350reflects the light, and the light travels parallel to the substrate surface towards the coordinate input region302. The light that travels through the space above the coordinate input region302is reflected by the light-receiving side reflective plate360and reaches the light-receiving elements of the light detector320.

In the electro-optical device300, which is configured as stated above, a position indicated by touching the coordinate input region302with a finger or an input stylus is received as input data by the light detectors320.

RELATED ART DOCUMENTS

Patent Documents

SUMMARY OF THE INVENTION

Problems to be Solved by the Invention

The light-receiving device220of the optical touch panel200of Patent Document 1 is provided externally to the display device230. The light-receiving device220is provided with a plurality of light-receiving elements221on one substrate222, and therefore, if the number of light-receiving elements221is increased in order to provide a larger or higher resolution display, the yield decreases.

In addition, if lenses L201and L202are provided for all light-emitting elements211and all light-receiving elements221as in the optical touch panel200, the cost of materials increases, thus resulting in the problem that the manufacturing cost is high.

Even in the case of the optical touch panel of Patent Document 2 in which the light-receiving elements are formed integrally with the element substrate, the yield decreases if the number of light-receiving elements is increased in order to provide a larger or higher resolution display, as in the optical touch panel200of Patent Document 1.

The present invention is made in view of the above-mentioned problems, and an object thereof is to provide a light-receiving device that is provided with light-receiving elements disposed continuously over a long distance at a high density, and an optical touch panel device provided therewith, while mitigating increases in manufacturing cost and decreases in yield.

Means for Solving the Problems

In order to solve the above-mentioned problems, a light-receiving device of the present invention includes a plurality of light-receiving units, wherein each of the plurality of light-receiving units has: a plurality of light-receiving elements; first and second terminal forming regions respectively provided for forming first and second connection terminals for connecting first and second circuits to the plurality of light-receiving elements, respectively; and a light-receiving element forming region disposed between the first and second terminal forming regions, the light-receiving element forming region being provided for forming the plurality of light-receiving elements, wherein each of the plurality of light-receiving units is provided with a substrate and a protective member, wherein the plurality of light-receiving elements and the first and second connection terminals are formed on a front surface of the substrate, wherein the protective member is disposed so as to cover the plurality of light-receiving elements, and wherein a rear surface of the first or second terminal forming region in the substrate of one of the light-receiving units and a front surface of the protective member of a light-receiving unit that is different from the aforementioned one of the light-receiving units are bonded together.

According to the above-mentioned configuration, the respective plurality of light-receiving units are constituted of first and second terminal forming regions for respectively forming first and second connection terminals for connecting the plurality of light-receiving elements to first and second circuits, respectively, and a light-receiving element forming region that is disposed between the first and second terminal forming regions and that is provided for forming the plurality of light-receiving elements.

With this configuration, the plurality of light-receiving elements are formed in the light-receiving element forming region, and a first connection terminal and a second connection terminal are formed in a first terminal forming region and a second terminal forming region, respectively. Thus, the plurality of light-receiving elements and the first and second circuits can be connected. With this configuration, the driving of the light-receiving element groups can be controlled and the output from the light-receiving element groups can be controlled based on first and second control circuits.

According to the above-mentioned configuration, the protective member is disposed so as to cover the plurality of light-receiving elements formed on the front surface of the substrate, and thus, it is possible to protect the plurality of light-receiving elements.

According to the above-mentioned configuration, of the substrates of the light-receiving units, the rear surface of the first or second terminal forming region and the front surface of the protective member of another light-receiving unit are bonded together. The first and second terminal forming regions are disposed with the light-receiving element forming region therebetween.

Thus, it is possible to dispose the respective light-receiving element forming regions so as to be adjacent to each other when viewing the plurality of light-receiving units bonded to each other from a plan view, and therefore it is possible to dispose the plurality of light-receiving elements formed in the respective light-receiving element forming regions so as to be adjacent. Thus, it is possible to dispose the plurality of light-receiving elements continuously over a long distance.

Because the plurality of light-receiving units are bonded together, even if the number of light-receiving elements formed increases by disposing the light-receiving elements continuously over a long distance, the yield can be prevented from decreasing compared to a case in which the same number of light-receiving elements are formed without bonding together the light-receiving units.

The above-mentioned configuration is constituted of the plurality of light-receiving units, and a light-receiving element group is formed for each of the plurality of light-receiving units. With this configuration, light-receiving elements are formed at a high density on each of the plurality of light-receiving units and light-receiving units in which the light-receiving elements are formed at a high density are bonded to each other, thus forming a light-receiving device in which light-receiving elements are formed at a high density while mitigating a decrease in yield.

Also, because it is possible to dispose the light-receiving elements at a high density as stated above, a decrease in resolution can be mitigated without disposing a member such as a lens to cover the light-receiving surfaces of all of the light-receiving elements, for example. Thus, it is possible to prevent the manufacturing cost from being greater than when a member such as a lens is disposed to cover the light-receiving surfaces of all of the light-receiving elements.

Effects of the Invention

The light-receiving device of the present invention includes a plurality of light-receiving units, wherein each of the plurality of light-receiving units has: a plurality of light-receiving elements; first and second terminal forming regions respectively provided for forming first and second connection terminals for connecting first and second circuits to the plurality of light-receiving elements, respectively; and a light-receiving element forming region disposed between the first and second terminal forming regions, the light-receiving element forming region being provided for forming the plurality of light-receiving elements, wherein each of the plurality of light-receiving units is provided with a substrate and a protective member, wherein the plurality of light-receiving elements and the first and second connection terminals are formed on a front surface of the substrate, wherein the protective member is disposed so as to cover the plurality of light-receiving elements, and wherein a rear surface of the first or second terminal forming region in the substrate of one of the light-receiving units and a front surface of the protective member of a light-receiving unit that is different from the aforementioned one of the light-receiving units are bonded together.

With this configuration, it is possible to provide a light-receiving device provided with light-receiving elements at a high density and continuously over a long distance, and an optical touch panel device provided therewith, while mitigating an increase in manufacturing cost and a decrease in yield.

DETAILED DESCRIPTION OF EMBODIMENTS

An embodiment of the present invention will be described in detail below.

(Schematic Configuration of an Optical Touch Panel Device)

FIG. 2(a) is a perspective view that shows an image display surface of an optical touch panel device100according to the present embodiment, andFIG. 2(b) is a cross-sectional view ofFIG. 2(a) along the line A-B.

As shown inFIG. 2(a), the optical touch panel device100is provided with a display panel101, light sources5, and light-receiving devices10.

The display panel101is an image display panel in general use such as a liquid crystal display panel or an organic EL (electroluminescence) display panel, and in particular, a large, approximately 65 inch image display panel. In describing the present embodiment, the display panel101is assumed to be a liquid crystal display panel.

The front surface of the display panel101is an image display surface that includes an image display region for displaying images. The image display region is also a coordinate input region102that receives tactile input from a stylus, a finger, or the like by the user in order to input coordinates to the display panel101.

The coordinate input region102(image display region) has a plurality of pixels, which are not shown in the drawings, arranged in a matrix form, and the display panel101can display images using the plurality of pixels.

The light sources5and the light-receiving devices10are arranged along the periphery of the display panel101, adjacent thereto.

The light sources5are disposed in light-emitting side periphery regions, which are regions located along the periphery of the coordinate input region102. Also, the light-receiving devices10are disposed in the light-receiving side periphery regions located along the periphery of the coordinate input region102, and face the light-emitting side periphery regions via the coordinate input region102. The region that is surrounded by the light-emitting side periphery regions and the light-receiving side periphery regions is the coordinate input region102(image display region) of the display panel101.

The light sources5and the light-receiving devices10form pairs and detect the coordinates at which a coordinate indicating member such as a stylus has come into contact with the coordinate input region102.

In the optical touch panel device100, a pair constituted of the light source5and the light-receiving device10for detecting an X direction coordinate and a pair constituted of the light source5and the light-receiving device10for detecting a Y direction coordinate are disposed in the periphery of the coordinate input region102.

In the light source5, a plurality of optical elements such as LEDs are arranged in a line, for example. The light-receiving device10is constituted of a plurality of light-receiving units10A,10B, and10C bonded together, as will be described below. The light-receiving units10A,10B, and10C each have a plurality of light-receiving elements12such as photodiodes arranged in a line or a plurality of lines. Details of the configuration of the light-receiving device10will be described below.

As shown inFIG. 2(b), the optical touch panel device100is additionally provided with a bezel107, and the display panel101is stored within the bezel107. The bezel107has an opening in the region that faces the coordinate input region102of the display panel101, which allows the user to view images displayed in the coordinate input region102of the display panel101or to bring an indicating member such as a stylus or a finger for inputting coordinates into contact with the coordinate input region102.

Also, the bezel107is provided with an edge part107athat covers the light sources5and the light-receiving surfaces12aof the light-receiving elements12. The inner surface of the edge part107a(the surface of the edge part107aon the side that faces the light source5and the light-receiving surface12aof the light-receiving element12) is provided with a reflective plate for reflecting light. The reflective plate covering the light source5is referred to as a light-emitting side reflective plate105, and the reflective plate covering the light-receiving surface12aof the light-receiving element12is referred to as a light-receiving side reflective plate110.

In the optical touch panel device100, the direction that the light is emitted from the light source5is perpendicular to the image display surface of the display panel101, and the light-receiving surfaces12aof the plurality of light-receiving elements12of the light-receiving device10are disposed parallel to the image display surface of the display panel101.

The light-emitting side reflective plate105covers the light-emitting surface of the light source5and is provided so as to extend in the direction that the light-emitting elements are aligned. The light-receiving side reflective plate110covers the light-receiving surfaces12aof the light-receiving elements12of the light-receiving device10, and is provided so as to extend in the direction that the plurality of light-receiving elements12are aligned.

The light-emitting side reflective plate105and the light-receiving side reflective plate110are made of a material with a high reflectance such as aluminum or glass, and are provided so as to be at an approximately 45° angle to the display surface of the display panel101.

With this configuration, the light emitted from the light source5is reflected by the light-emitting side reflective plate105so as to travel parallel to the display surface of the display panel101. The light that was emitted by the light source5and reflected by the light-emitting side reflective plate105is then reflected by the light-receiving side reflective plate110and received by the light-receiving element12of the light-receiving device10.

When the user brings a stylus or the like in contact with the coordinate input region102of the display panel101in order to input coordinates to the optical touch panel device100, the light emitted from the light source5is blocked by the stylus. The optical touch panel device100detects the X-direction and Y-direction coordinates of the position where the light is blocked using the light-receiving device10, which allows the touch panel function to be realized.

As stated above, the light-receiving device10is constituted of the plurality of light-receiving units10A,10B, and10C, which are bonded together. In addition, as will be described below, the light-receiving units10A,10B, and10C are provided with light-receiving elements at a high density.

Because the plurality of light-receiving elements12are formed at a high density on each of the light-receiving units10A,10B, and10C, which are bonded together, a decrease in yield can be mitigated and the touch position can be detected with a high resolution.

Also, the optical touch panel device100is provided with a light-receiving device10having the light-receiving elements12disposed continuously over a long distance, which allows the coordinate input region102that detects a touch position to be made large.

The optical touch panel device100is provided with the light-receiving device10in this manner, thus enabling a large 65 inch optical touch panel device100to be configured, and even if the user brings an indicating member with a relatively thin tip such as a stylus into contact with the coordinate input region102, for example, the contact position of the indicating member can be detected accurately by the light-receiving device10.

Next, the configuration of the light-receiving device10will be described with reference toFIGS. 1 and 2.

FIG. 1is a cross-sectional view that shows a configuration of the light-receiving device10according to Embodiment 1.

The light-receiving units10A,10B, and10C are respectively constituted of first terminal forming regions16Ab,16Bb, and16Cb, second terminal forming regions16Ac,16Bc, and16Cc, and light-receiving element forming regions16Aa,16Ba, and16Ca.

The first terminal forming regions16Ab,16Bb, and16Cb are regions for forming the connection pads (first connection terminals) PAb, PBb, and PCb for connecting the first circuit to the plurality of light-receiving elements12. The second terminal forming regions16Ac,16Bc, and16Cc are regions for forming connection pads (second connection terminals) PAc, PBc, and PCc for connecting the second control circuit to the plurality of light-receiving elements12.

The light-receiving element forming regions (sensor regions)16Aa,16Ba, and16Ca are regions disposed between the first terminal forming regions16Ab,16Bb, and16Cb, and the second terminal forming regions16Ac,16Bc, and16Cc, and are regions for forming the plurality of light-receiving elements12.

The light-receiving units10A,10B, and10C are respectively provided with element substrates (substrates)11A,11B, and11C, and sheets of cover glass (protective members)14A,14B, and14C.

On the front surfaces of the element substrates (substrates)11A,11B, and11C, light-receiving element groups12A,12B, and12C constituted of a plurality of light-receiving elements12are formed on the light-receiving element forming regions16Aa,16Ba, and16Ca, which are the central regions. In the first terminal forming regions16Ab,16Bb, and16Cb, the connection pads PAb, PBb, and PCb are formed, and connection pads PAc, PBc, and PCc are formed in the second terminal forming regions16Ac,16Bc, and16Cc.

The sheets of cover glass14A,14B, and14C are formed so as to cover the light-receiving element groups12A,12B, and12C. With this configuration, the sheets of cover glass14A,14B, and14C can protect the light-receiving element groups12A,12B, and12C. Members that cover the light-receiving element groups12A,12B, and12C in this manner need only to protect the light-receiving element groups12A,12B, and12C, and a transparent resin material may be used instead of the sheets of cover glass14A,14B, and14C.

The rear surface of the second terminal forming region16Ac of the element substrate11A of the light-receiving unit10A and the front surface of the cover glass14B that covers the light-receiving element group12B of the light-receiving unit10B are bonded together.

Also, the rear surface of the first terminal forming region16Cb of the element substrate11C of the light-receiving unit10C and the front surface of the cover glass14B that covers the light-receiving element group12B of the light-receiving unit10B are bonded together.

The rear surface of the first terminal forming region16Ab of the element substrate11A of the light-receiving unit10A and the rear surface of the second terminal forming region16Cc of the element substrate11C of the light-receiving unit10C are each provided with a spacer9. The spacers9and the rear surface of the element substrate11B of the light-receiving unit10B are provided with a RIM sheet (double-sided tape)8. The light-receiving device10is bonded to the bottom surface of the inner side of the bezel107with the RIM sheet8. The spacer9can be made of dummy glass, for example, and sets the height (distance from the bottom surface of the bezel107) of the light-receiving units10A and10C.

As shown inFIGS. 1 and 2, when viewing the light-receiving device10from a plan view, the light-receiving units10A,10B, and10C are bonded to each other such that the light-receiving element groups12A,12B, and12C form a straight line.

In each of the light-receiving element groups12A,12B, and12C provided in the individual light-receiving units10A,10B, and10C, a plurality of light-receiving elements12are provided in a line at a high density in the light-receiving element forming regions16Aa,16Ba,16Ca. With this configuration, light-receiving units10A,10B, and10C, which are provided with light-receiving elements12provided continuously over a long distance at a high density, are configured. Each of the light-receiving element groups12A,12B, and12C is not limited to being formed in a line, and may be formed in a plurality of parallel lines.

In the light-receiving device10, the respective light-receiving units10A,10B, and10C have: the light-receiving element groups12A,12B, and12C formed in the light-receiving element forming regions16Aa,16Ba, and16Ca; the connection pads PAb, PBb, and PCb formed in the first terminal forming regions16Ab,16Bb, and16Cb; and the connection pads PAc, PBc, and PCc formed in the second terminal forming regions16Ac,16Bc, and16Cc. Thus, the light-receiving element groups12A,12B, and12C, the first circuit, and the second circuit can be connected.

With this configuration, the driving of the light-receiving element groups12A,12B, and12C can be controlled by the first circuit and the second circuit, and the output from the light-receiving element groups12A,12B, and12C can be controlled.

Of the element substrate (substrate)11A, the rear surface of the second terminal forming region16Ac, which is one of the regions between which the light-receiving element forming region16Aa is disposed, and the front surface of the cover glass14B, which covers the light-receiving element group12B of the light-receiving unit10B, are bonded together. Of the element substrate11C, the rear surface of the first terminal forming region16Cb, which is one of the regions that sandwich the light-receiving element forming region16Ca, and the front surface of the cover glass14B, which covers the light-receiving element groups12B of the light-receiving unit10B, are bonded together.

Thus, the light-receiving element forming regions16Aa,16Ba, and16Ca can be disposed adjacent to each other when viewing the light-receiving device10from a plan view. Therefore, it is possible to dispose the light-receiving element groups12A,12B, and12C, which are formed on the respective light-receiving element forming regions, so as to be adjacent to each other and continuous.

As will be described below, the light-receiving units10A,10C, and10B are bonded to each other such that the light-receiving element groups12A and12C disposed on the light-receiving units10A and10C, and the light-receiving element group12B disposed on the light-receiving unit10B are arranged in a line when viewing the light-receiving device10from a plan view. The plurality of light-receiving elements12are disposed in this manner in the light-receiving device10at a high density and continuously over a long distance.

The light-receiving element groups12A and12C, and the light-receiving element group12B do not need to be in one line, and may be arranged in a plurality of lines. In other words, the light-receiving units10A and10C, and the light-receiving unit10B simply need to be bonded to each other such that the light-receiving element groups12A and12C disposed on the light-receiving units10A and10C, and the light-receiving element group12B disposed on the light-receiving unit10B are aligned with an even gap therebetween, when viewing the light-receiving device10from a plan view.

In the light-receiving device10, the light-receiving units10A,10B, and10C are bonded together, and thus, even if the number of light-receiving elements12increases as a result of the light-receiving element groups12A,12B, and12C being disposed over a long distance continuously, the yield can be prevented from decreasing compared to when the same number of light-receiving elements12is formed in the light-receiving device10without the light-receiving units being bonded together.

Also, the light-receiving device10is constituted of a plurality of light-receiving units10A,10B, and10C, and a plurality of light-receiving elements12are formed on each of the plurality of light-receiving units10A,10B, and10C. With this configuration, the light-receiving elements12are formed on each of the plurality of light-receiving units10A,10B, and10C at a high density, and by bonding the light-receiving units10A,10B, and10C, on which the light-receiving elements12are formed at a high density, to each other, a decrease in yield can be mitigated and it is possible to configure a light-receiving device10on which the light-receiving elements12are formed at a high density.

Also, since it is possible to dispose the light-receiving elements12at a high density, it is possible to mitigate a decrease in resolution without disposing a member such as a lens to cover the light-receiving surfaces of all of the light-receiving elements as in the optical touch panel200shown inFIG. 12, for example.

Thus, by using the light-receiving device10configured in this manner as a coordinate detection light-receiving device of an optical touch panel device100as described above, it is possible to mitigate an increase in manufacturing cost compared to when a member such as a lens is disposed to cover the light-receiving surfaces of all light-receiving elements as in the optical touch panel200.

Also, while the optical touch panel device100is a large, approximately 65 inch display device, for example, the optical touch panel device100can detect the position of a stylus or the like that has come into contact even if the stylus or the like that has come in to contact with the coordinate input region102is relatively thin, and the position thereof can be detected at a high resolution.

Thus, the optical touch panel device100is particularly suitable as an optical touch panel provided in an electronic device that needs to detect the input position accurately and that needs to be a large display panel.

In addition, the light-receiving device10is made such that the amount of light entering the light-receiving elements12in the light-receiving unit10B in the regions surrounded by the dotted lines C and D inFIG. 1is maximized, thus preventing a sensing dead zone from forming in the regions surrounded by the dotted lines C and D. Details concerning this will be described below.

In addition, the first terminal forming region16Ab and the second terminal forming region16Ac of the light-receiving unit10A are each provided with a lens18Ab and a lens18Ac, which are lenticular lenses or the like. With this configuration, the amount of light entering the light-receiving element group12B disposed on the rear surface side of the first terminal forming region16Ab and the second terminal forming region16Ac of the element substrate11A, can be increased. Thus, it is possible to mitigate a decrease in the amount of light received by the light-receiving element group12B disposed on the rear surface of the element substrate11A.

The first terminal forming region16Cb and the second terminal forming region16Cc of the light-receiving device10C are also each provided with a lens18Cb and a lens18Cc, which are lenticular lenses or the like. With this configuration, the amount of light entering the light-receiving element group12B disposed on the rear surface side of the first terminal forming region16Cb and the second terminal forming region16Cc of the element substrate11C, can be increased. Thus, it is possible to mitigate a decrease in the amount of light received by the light-receiving element group12B disposed on the rear surface of the element substrate11C.

In the light-receiving device10, the cover glass14B of the light-receiving unit10B and the rear surfaces of the element substrates11A and11C of the light-receiving units10A and10C are bonded together, and thus, the light-receiving surface of the light-receiving element groups12A and12C, and the light-receiving surface of the light-receiving element group12B have different distances from the light source, thus resulting in the amount of light received differing.

When the optical touch panel device100is turned on, calibration is conducted in the light-receiving device10after the initial distribution of the amount of light received by each light-receiving element12in the light-receiving element groups12A,12B, and12C is recorded. Then, when operating the optical touch panel device100, the difference of the profile of the amount of light received by each light-receiving element12during operation and the distribution of the amount of light initially received is calculated, thus detecting whether or not a finger, a stylus, or the like is in contact with the touch panel. Therefore, the light-receiving device10can obtain an even light-receiving signal as a result of the light-receiving element groups12A,12B, and12C, thus allowing accurate sensing.

Also, it is preferable that the light-receiving unit10B be as thin as possible in order to minimize amount of space between the light-receiving units10A and10C and the bezel107.

Next, the configuration of the light-receiving units10A,10B, and10C, which constitute the light-receiving device10will be described with reference toFIGS. 3(a) and3(b). Also, while the configuration of the light-receiving unit10A will be described based onFIGS. 3(a) and3(b), descriptions of the light-receiving units10B and10C will be omitted since the configuration thereof is similar to that of the light-receiving unit10A.

FIG. 3(a) is a plan view that shows the configuration of the light-receiving unit10A, andFIG. 3(b) is a cross-sectional view that shows the configuration of the light-receiving unit10A. InFIG. 3(b), the light enters from the left side of the page.

As shown inFIGS. 3(a) and3(b), the light-receiving unit10A is provided with an element substrate11A, the light-receiving element group12A constituted of a plurality of light-receiving elements12, a resin BM (black matrix)13A, and a cover glass14A.

The element substrate11A is made of glass (non-alkali glass or the like) or the like with a thickness of approximately 1.7 mm, for example. The central region of the element substrate11A is provided with the light-receiving element group12A provided with a plurality of light-receiving elements12arranged in one line. The light-receiving element12is made of a photodiode, for example.

The resin BM (black matrix)13A is formed on the rear surface of the cover glass14A, and is bonded to the element substrate11A while being separated from the light-receiving element group12A as a result of the protective seal15A. The resin BM13A is patterned on the rear surface of the cover glass14A so as not to cover the individual light-receiving surfaces of the light-receiving element group12A.

As shown inFIG. 3(a), the light-receiving unit10A is constituted of a light-receiving element forming region16Aa, which is a region provided with the light-receiving element group12A in which a plurality of light-receiving elements12are arranged in a line, and a first terminal forming region16Ab and a second terminal forming region16Ac, which are regions in which terminals for external connections are formed.

Of the rear surface of the element substrate11A, at least one of the first terminal forming region16Ab and the second terminal forming region16Ac is a region to be bonded to the front surface of the cover glass14B (14C) of the other light-receiving unit10B (10C).

When viewing the light-receiving unit10A from a plan view, the long side direction of the element substrate11A is the Y direction and the short side direction intersecting perpendicularly to the long side direction is the X direction. The light-receiving elements12are aligned in one line in the Y direction.

The length of the element substrate11A in the X direction is approximately 3 mm, and the Y direction thereof is approximately 210 mm. The element substrate11A is provided with the first terminal forming region16Ab of approximately 5 mm, the light-receiving element forming region16Aa of approximately 200 mm, and the second terminal forming region16Ac of approximately 5 mm, aligned in this order in the Y direction.

In the light-receiving element forming region16Aa, the plurality of light-receiving elements12are provided at a high density at regular intervals with a pitch of approximately 100 μm to 1000 μm, for example.

The resin BM13A is formed in the periphery of the light-receiving element group12A. By forming the resin BM13A in this manner, it is possible to shield the light-receiving surfaces of the light-receiving element group12A from light entering from the diagonal direction or the horizontal direction, thus preventing excess light from entering the light-receiving element group12A. With this configuration, it is possible to increase the sensitivity of the light-receiving element groups12A to light entering from the vertical direction.

One terminal of an FPC17A, which is approximately 4.5 mm in width (Y direction length), is connected to the first terminal forming region16Ab. This terminal of the FPC (flexible printed circuit)17A is connected to the connection pads PAb, and the connection pads PAb are connected to output electrodes of the respective light-receiving elements12. The other terminal of the FPC17A is provided with an ADC (AD converter)-IC21A, and the connection pads PAb and the ADC-IC21A are connected to each other. The FPC17A can connect to external elements via the ADC-IC21A. With this configuration, when currents corresponding to the amounts of light received flow from the light-receiving element group12A via the output electrodes, the ADC-IC21A converts the currents to digital data and outputs it to external elements.

A terminal of an SOF (system on file)19A of approximately 4.5 mm in width (Y direction length) is connected to the second terminal forming region16Ac. This terminal of the SOF19A is connected to the connection pads (connection terminals) PAc, and the respective connection pads PAc are connected to control electrodes of respective light-receiving elements12. The other terminal of the SOF19A is provided with a sensor control IC22A, and the connection pads PAc and the sensor control IC22A are connected in the SOF19A. The SOF19A can connect to external elements via the sensor control IC22A. With this configuration, drive control can be conducted on the light-receiving element group12A.

The second terminal forming region16Ac of the light-receiving unit10A is provided with a light-receiving element overlapping region21Ac that is disposed adjacent to the connection pads PAc formed therein and that overlaps some of the light-receiving element group12B of the light-receiving unit10B.

Also, the first terminal forming region16Ab of the light-receiving unit10A is provided with a light-receiving element overlapping region21Ab that is disposed adjacent to the connection pads PAb formed therein and that overlaps some of the light-receiving element group12B of the light-receiving unit10B.

When viewing the light-receiving device10from a plan view, the light-receiving unit10A and the light-receiving unit10B are bonded together such that some of the light-receiving element group12B of the light-receiving unit10B in the bonded region are included in at least one of the light-receiving element overlapping region21Ab and the light-receiving element overlapping region21Ac.

With this configuration, some of the light-receiving element group12B of the light-receiving unit10B overlaps with the light-receiving element overlapping region21Ab or the light-receiving element overlapping region21Ac so as to be adjacent to the connection pads PAb or the connection pads PAc of the light-receiving unit10A, and thus, it is possible to dispose some of the light-receiving element group12B of the light-receiving unit10B without overlapping with the connection pads PAb or alternatively the connection pads PAc of the light-receiving unit10A. With this configuration, it is possible to increase the amount of light received by the light-receiving element group12B of the light-receiving unit10B disposed in the light-receiving element overlapping regions21Ab and21Ac of the light-receiving unit10A.

Similar to the light-receiving device10ofFIG. 1, when bonding only the second terminal forming region16Ac out of the first terminal forming region16Ab and the second terminal forming region16Ac of the light-receiving unit10A to the other light-receiving unit10B, the light-receiving element overlapping region21Ab of the first terminal forming region16Ab may be omitted.

The light-receiving element overlapping regions21Ab and21Ac are regions for including the light-receiving element group12B of the light-receiving unit10B from a plan view when bonding together the rear surface of the element substrate11A of the light-receiving unit10A and the cover glass14B of the light-receiving unit10B, which is different from the light-receiving unit10A.

Thus, the area of the wiring lines entering the light-receiving element overlapping regions21Ab and21Ac is minimized.

Specifically, the light-receiving element overlapping regions21Ab and21Ac are configured such that (i) Y direction wiring lines do not enter the light-receiving element overlapping regions21Ab and21Ac, (ii) X direction wiring lines do necessarily enter but the width thereof is minimized, (iii) the wiring lines are disposed at regular intervals and bonded together, allowing light to enter the light-receiving element group12B (12C) of the light-receiving unit10B (10C) disposed on the rear surface side.

As described above, from a plan view, the wiring lines formed in the first terminal forming region16Ab and the second terminal forming region16Ac (overlapping part) of the light-receiving unit10A are configured so as to avoid the light-receiving element group12B (12C) of the light-receiving unit10B (10C) disposed on the rear side, thus removing sensing dead zones in the first terminal forming region16Ab and the second terminal forming region16Ac. Details thereof will be described below.

Alignment marks23for patterning wiring lines for the light-receiving element group12A and the like are formed in the four corners of the element substrate11A.

Lenses (first lenses)18Ab and18Ac are disposed on the front surface of the element substrate11A of the light-receiving unit10A in the light-receiving element overlapping regions21Ab and21Ac. The lenses18Ab and18Ac are arranged so as to extend in the direction that the light-receiving element group12A is aligned. The lenses18Ab and18Ac are lenticular lenses, for example. The lenses18Ab and18Ac are provided so as to include the light-receiving element overlapping regions21Ab and21Ac.

The lenses18Ab and18Ac can condense light and thus, it is possible to mitigate a decrease in the amount of light received by the light-receiving element group12B of the light-receiving unit10B provided in the light-receiving element overlapping regions21Ab and21Ac of the light-receiving unit10A.

Next, a manufacturing method for the light-receiving unit10A will be described.

The light-receiving unit10A can be made through TFT processing by which general liquid crystal display panels are manufactured, for example.

The light-receiving element group12A is formed on the element substrate11A. The light-receiving element group12A is made of photodiodes or the like, and can be made by the same process as the TFTs formed in the respective pixels as switching elements for each pixel of the display panel101. When forming the light-receiving element group12A on the element substrate11A, wiring lines that connect the output electrodes of the light-receiving element group12A to the connection pads PAb, wiring lines that connect control electrodes of the light-receiving element group12A to the connection pads PAc, and the like are formed at the same time.

Next, the resin BM13A is patterned on the rear surface of the cover glass14A so as not cover the light-receiving element group12A.

Next, the cover glass14A, the rear surface of which has a resin BM13A patterned thereon, is bonded to the element substrate11A using the protective seal15A. The cover glass14A of the first terminal forming region16Ab and the second terminal forming region16Ac is cut.

Next, the connection pads PAb and PAc for connecting the FPC17A and the SOF19A are formed in the first terminal forming region16Ab and the second terminal forming region16Ac, respectively. The connection pads PAb, which are formed in the first terminal forming region16Ab, are connected to the FPC17A, and the SOF19A is connected to the connection pads PAc formed in the second terminal forming region16Ac.

It is possible to form the light-receiving unit10A in this manner. Also, the light-receiving units10B and10C can be formed in a similar manner.

In the light-receiving device10, the light-receiving element groups12A,12B, and12C are respectively formed on the light-receiving units10A,10B, and10C, which constitute the light-receiving device10. The light-receiving device10is formed by bonding together the light-receiving units10A,10B, and10C on which the light-receiving element groups12A,12B, and12C are formed, thus mitigating a decrease in yield, and allowing the light-receiving elements12to be arranged at a high density and over a long distance.

(Wiring Lines that Connect the Light-receiving Elements to the Connection Pads)

Next, a method for decreasing the area of the wiring lines entering the light-receiving element overlapping regions21Ab and21Ac is described.

First, usingFIG. 4, a method for drawing out the wiring lines that connect the light-receiving element group12A and the connection pads PAc for connecting to the SOF19A is described.

FIG. 4is a drawing that shows a configuration of the second terminal forming region16Ac of the light-receiving device10A.

The connection pads PAc are constituted of connection pads PAc1, PAc2, . . . PAcn-2, PAcn-1, and PAcnaligned in that order in the Y direction.

Each of the connection pads PAc1, PAc2, . . . PAcn-2, PAcn-1, and PAcnis connected to one terminal of respective light-receiving element control wiring lines (horizontal direction wiring lines)24x1,24x2, . . .24xn-2,24xn-1, and24xn.

The light-receiving element control wiring lines24x1,24x2, . . .24xn-1, and24xnextend in the X direction while crossing the light-receiving element overlapping region21Ac and are aligned in the Y direction so as to be parallel.

The light-receiving element control wiring lines24x1,24x2, . . .24xn-1,24xnare formed so as to be thin at approximately 100 μm such that light enters the light-receiving element group12B disposed in an overlapping manner on the rear surface side of the light-receiving element overlapping region21Ac.

With this configuration, the light-receiving element control wiring lines24x1,24x2, . . .24xn-1, and24xncan be provided with a wide gap therebetween, and thus, it is possible to prevent a decrease in the sensitivity to received light of the light-receiving element group12B disposed in an overlapping manner on the rear surface side of the light-receiving element overlapping region21Ac.

The other terminal of the light-receiving element control wiring lines24x1,24x2, . . .24xn-2,24xn-1, and24xnis respectively connected to the one terminal of light-receiving element control wiring lines (vertical direction wiring lines)24y1,24y2, . . .24yn-2,24yn-1, and24yn.

The light-receiving element control wiring lines24y1,24y2, . . .24yn-1, and24ynextend in the Y direction and aligned in the X direction so as to be parallel. In other words, each of the light-receiving element control wiring lines24y1,24y2, . . .24yn-1, and24ynis disposed adjacent to the light-receiving element overlapping region21Ac, and extends in the direction that the light-receiving element overlapping region21Ac extends.

With this configuration, each of the Y direction light-receiving element control wiring lines24y1,24y2, . . .24yn-1, and24yn, which are wide, do not enter the light-receiving element overlapping region21Ac.

The width of each of the light-receiving element control wiring lines24y1,24y2, . . .24yn-1, and24ynis approximately 50 μm to 500 μm and preferably greater than 100 μm and no greater than 500 μm, thus being wider than the light-receiving element control wiring lines24x1,24x2, . . .24xn-1, and24xn. With this configuration, the resistance of the wiring lines can be decreased.

Where the respective light-receiving element control wiring lines24y1,24y2, . . .24yn-1, and24yn, which extend from one of the terminals in the Y direction (Y plus direction), reach beyond the position of the side part of the SOF19A, the width of the wiring lines becomes similar to that of the light-receiving element control wiring lines24x1,24x2, . . .24xn-1, and24xn, and the light-receiving element control wiring lines24y1,24y2, . . .24yn-1, and24ynare disposed so as to bend in a direction so as to cross the light-receiving element overlapping region21Ac again.

Each of the light-receiving element control wiring lines24y1,24y2, . . .24yn-1, and24yn, which cross the light-receiving element overlapping region21Ac, widens again to a width of approximately 50 μm to 500 μm and preferably greater than 100 μm and no greater than 500 μm, and extends in the Y direction connecting to the control electrode of each light-receiving element12.

In this manner, of the wiring lines that are connected from the sensor control IC to the control electrodes of the light-receiving element group12A in order to control the driving of the light-receiving elements12, the wiring lines formed in the light-receiving element overlapping region21Ac are relatively thin.

FIG. 5is a drawing that shows where the light-receiving unit10A and the light-receiving unit10B according to the present embodiment are bonded together.

As shown inFIG. 5, the front surface of the cover glass14B in the vicinity of the first terminal forming region16Bb of the light-receiving unit10B is bonded to the rear surface of the second terminal forming region16Ac of the light-receiving unit10A, for example.

As stated above, the second terminal forming region16Ac of the light-receiving unit10A is provided with: the light-receiving element control wiring lines24x1,24x2, . . .24xn-1, and24xn, which extend from the connection pads PAc and cross the light-receiving element overlapping region21Ac; and the vertical direction light-receiving element control wiring lines24y1,24y2, . . .24yn-1, and24yn, which extend from the light-receiving element control wiring lines24x1,24x2, . . .24xn-1, and24xnalong the direction in which the light-receiving element overlapping region21Ac extends, or in other words, the direction in which the light-receiving element group12A of the light-receiving unit10A is aligned in the light-receiving element overlapping region21Ac.

With this configuration, the amount of light blocked from entering the light-receiving element group12B in the light-receiving unit10B disposed in the light-receiving element overlapping region21Ac as a result of the light-receiving element control wiring lines24x1,24x2, . . .24xn-1, and24xn, which cross the light-receiving element overlapping region21Ac, can be minimized. As a result, it is possible to mitigate a decrease in the light received by the light-receiving element group12B of the light-receiving unit10B disposed in the light-receiving element overlapping region21Ac of the light-receiving unit10A.

Even if approximately 2 to 3 mm of the second terminal forming region16Ac of the light-receiving unit10A and the first terminal forming region16Bb of the light-receiving unit10B were bonded together, it is possible to allow enough light to enter the part of the light-receiving element group12B included in the region that is bonded together.

The light-receiving element control wiring lines24x1,24x2, . . .24xn-1, and24xnand the like, which cross the light-receiving element overlapping region21Ac, are disposed in a layer below the lens18Ac (between the lens18Ac and the element substrate11A).

The same is true with regard to drawing out of wiring lines that connect the light-receiving element group12A for when the rear surface of the element substrate11A of the first terminal forming region16Ab of the light-receiving unit10A is bonded to the cover glass14B in the vicinity of the second terminal forming region16Bc of the light-receiving unit10B, to the connection pads PAb for connecting to the FPC17A.

This is described with reference toFIG. 6.

FIG. 6is a drawing that shows a configuration of the first terminal forming region16Ab of the light-receiving unit10A.

The connection pads PAb are constituted of the connection pads PAb1, PAb2, PAb3, . . . PAbm-1, and PAbm, which are aligned in the Y direction in this order.

The light-receiving element output wiring lines25x1,25x2,25x3, . . .25xm-1, and25xmcross the light-receiving element overlapping region21Ab extending along the X direction and being disposed parallel to each other in the Y direction.

The width of the light-receiving element output wiring lines25x1,25x2, . . .25xm-1, and25xmis similar to the above-mentioned light-receiving element control wiring lines24x1,24x2, . . . , and24xnin being thin at approximately 100 μm so as to allow light to enter the light-receiving element group12B disposed in an overlapping manner on the rear surface side of the light-receiving element overlapping region21Ab.

With this configuration, the light-receiving element output wiring lines25x1,25x2, . . .25xm-1, and25xmare provided with a wide gap therebetween, and thus, when disposing the light-receiving element group12B in an overlapping manner on the rear surface side of the light-receiving element overlapping region21Ab, the sensitivity of the light-receiving element group12B to incident light can be prevented from decreasing.

The other terminals of the respective light-receiving element output wiring lines25x1,25x2, . . .25xm-1, and25xmare connected to terminals of respective light-receiving element output wiring lines (vertical direction wiring lines)25y1,25y2,25y3, . . .25ym-1, and25ym.

The respective light-receiving element output wiring lines25y1,25y2,25y3, . . .25ym-1, and25ymextend in the Y direction and are disposed parallel to each other in the X direction. In other words, the respective light-receiving element output wiring lines25y1,25y2,25y3, . . .25ym-1, and25ymare disposed adjacent to the light-receiving element overlapping region21Ab so as to extend along the direction that the light-receiving element overlapping region21Ab extends.

The width of each of the light-receiving element output wiring lines25y1,25y2,25y3, . . .25ym-1, and25ymis approximately 50 μm to 500 μm, and preferably greater than 100 μm and no greater than 500 μm, so as to be wider than the light-receiving element output control wiring lines25x1,25x2, and25xn. With this configuration, it is possible to have the effect of reducing the resistance of the wiring lines.

In this manner, the Y direction light-receiving element output wiring lines25y1,25y2,25y3, . . .25ym-1, and25ym, which are wide, do not enter the light-receiving element overlapping region21Ab.

Where the respective light-receiving element output wiring lines25y1,25y2,25y3, . . .25ym-1, and25ym, which extend from the one terminal in the Y direction (Y minus direction), reach beyond the position of the side part of the FPC17A, the width of the wiring lines becomes the same as that of the light-receiving element output wiring lines25x1,25x2, . . .25xm-1, and25xm, and the light-receiving element output wiring lines25y1,25y2,25y3, . . .25ym-1, and25ymare disposed so as to bend in a direction so as to cross the light-receiving element overlapping region21Ab again.

Each of the light-receiving element output wiring lines25y1,25y2,25y3, . . .25ym-1, and25ym, which cross the light-receiving element overlapping region21Ab, becomes wide again at approximately 50 μm to 500 μm and preferably greater than 100 μm and no greater than 500 μm, and extends in the Y direction connecting to the output electrode of each light-receiving element12.

In this manner, the first terminal forming region16Ab of the light-receiving unit10A is provided with the light-receiving element output wiring lines25x1,25x2, . . .25xm-1, and25xm, which extend from the connection pads PAb and cross the light-receiving element overlapping region21Ab, and the light-receiving element output wiring lines25y1,25y2,25y3, . . .25ym-1, and25ym, which extend from the light-receiving element output wiring lines25x1,25x2, . . .25xm-1, and25xmalong the direction in which the light-receiving element group12B of the light-receiving unit10B in the light-receiving element overlapping region21Ab are aligned.

With this configuration, the amount of light blocked from entering the light-receiving element group12B in the light-receiving unit10B, which is disposed in the light-receiving element overlapping region21Ab of the light-receiving unit10A, as a result of the light-receiving element output wiring lines25x1,25x2, . . .25xm-1, and25xm, which cross the light-receiving element overlapping region21Ab, can be minimized. As a result, it is possible to mitigate a decrease in the amount of light received by the light-receiving element group12B of the light-receiving unit10B disposed in the light-receiving element overlapping region21Ab of the light-receiving unit10A.

Wiring lines that cross the light-receiving element overlapping region21Ab such as the light-receiving element output wiring lines25x1,25x2,25x3, . . .25xm-1, and25xmare disposed in a layer below the lens18Ab (between the lens18Ab and the element substrate11A).

The same is true with regard to drawing out the wiring lines that connect the light-receiving element group12C for when the rear surface of the element substrate11C of the first terminal forming region16Cb of the light-receiving unit10C is bonded to the cover glass14B in the vicinity of the second terminal forming region16Bc of the light-receiving unit10B, to the connection pads PCb for connecting to the FPC17C.

Next, a configuration of a light-receiving device50according to Embodiment 2 will be described with reference toFIGS. 7 and 8. For ease of description, members having the same functions as those in the drawings for Embodiment 1 are assigned the same reference characters and descriptions thereof will be omitted.

FIG. 7is a cross-sectional view that shows a configuration of a light-receiving device50according to Embodiment 2.

The light-receiving device50differs from the light-receiving device10in that the light-receiving device50is provided with additional lenses in the region where a light-receiving unit10A and a light-receiving unit10B are bonded together, and the region where a light-receiving unit10B and a light-receiving unit10C are bonded together.

In the second terminal forming region16Ac of the light-receiving unit10A, a lenticular lens (second lens)28Ad is provided on the rear surface of an element substrate11A. The region facing the lens28Ad, which is the front surface of a cover glass14B of the light-receiving unit10B, is also provided with a lenticular lens (third lens)28Bb.

A spacer29is provided between the rear surface of the element substrate11A of the light-receiving unit10A and the front surface of the cover glass14B of the light-receiving unit10B. The rear surface of the element substrate11A is bonded to the front surface of the cover glass14B of the light-receiving unit10B using the spacer29.

In the first terminal forming region16Cb of the light-receiving unit10C, a lenticular lens (second lens)28Cd is provided on the rear surface of an element substrate11C. The region facing the lens28Cd, which is the front surface of the cover glass14B of the light-receiving unit10B, is also provided with a lenticular lens (third lens)28Bc.

The spacer29is provided between the rear surface of the element substrate11C of the light-receiving unit10C and the front surface of the cover glass14B of the light-receiving unit10B. The rear surface of the element substrate11C and the front surface of the cover glass14B of the light-receiving unit10B are bonded together using the spacer29.

FIG. 8is a drawing that shows a region where the light-receiving unit10A and the light-receiving unit10B of the light-receiving device50are bonded together.

As shown inFIG. 8, the lenses18Ac,28Ad, and28Bd are formed on the front surface and rear surface of the element substrate11A of the light-receiving unit10A, and the front surface of the cover glass14B of the light-receiving unit10B. The lenses18Ac,28Ad, and28Bd are lenticular lenses in which small convexities are present in a continuous fashion. The lenses18Ac,28Ad, and28Bd are disposed such that the respective convexities correspond.

The lens18Ac is formed so as to cover wiring lines such as light-receiving element control wiring lines24x1,24x2, . . .24xn-1, and24xn, which are formed so as to cross the light-receiving element overlapping region21Ac. The lens18Ac is disposed such that the convexities thereof face the direction from which light enters.

The lens28Ad is disposed on the rear surface of the element substrate11A so as to correspond to the lens18Ac, and the direction in which light, which is transmitted through the lens18Ac, is emitted is the direction that the convexities of the lens28Ad face.

The lens28Bd is disposed on the front surface of the cover glass14B so as to correspond to the lens28Ad, and is disposed such that the convexities thereof face the direction from which light that is transmitted through the lens28Ad enters. The direction that the convexities of the lenses18Cb,28Cd, and28Bc face is set in a similar manner.

In this manner, the light-receiving device50is provided with lenticular lenses18Ac and28Ad on the front and rear surfaces of the second terminal forming region16Ac of the element substrate11A of the light-receiving unit10A, and by disposing the lenticular lens28Bb on the front surface of the cover glass14B of the light-receiving unit10B, it is possible to improve the usage efficiency of the light as well as form parallel beams thereof.

With this configuration, it is possible to improve the usage efficiency of the light that enters the light-receiving element group12B disposed on the rear surface side of the second terminal forming region16Ac. Therefore, of the light-receiving element group12B disposed in the light-receiving unit10B, the strength of the light entering the light-receiving elements12in the region overlapping with the light-receiving unit10A can be made approximately the same as the strength of the light entering the light-receiving elements12that are not overlapping with the light-receiving unit10A.

Therefore, it is possible to mitigate a decrease in the amount of light received in the light-receiving elements12in the region where the light-receiving unit10A and the light-receiving unit10B are bonded together. Also, similar effects can be attained in the region where the light-receiving unit10C and the light-receiving unit10B are bonded together.

In this manner, in the light-receiving device50, the lens28Ad is disposed on the rear surface of the element substrate11A in the second terminal forming region16Ac of the light-receiving unit10A, and in addition, a lens28Bb is disposed on the front surface of the cover glass14B of the light-receiving unit10B, which is the region facing the lens28Ad.

In addition, the lens28Cd is disposed on the rear surface of the element substrate11C in the first terminal forming region16Cb of the light-receiving unit10C, and the lens28Bc is disposed on the front surface of the cover glass14B of the light-receiving unit10B, which is the region facing the lens28Cd.

According to the above-mentioned configuration, light is condensed and refracted as a result of the lenses18Ac,28Ad, and28Bb, and lenses18Cb,28Cd, and28Bc, thus mitigating a decrease in the amount of light received by the light-receiving element group12B of the light-receiving unit10B disposed in the light-receiving element overlapping region21Ac of the light-receiving unit10A and the light-receiving element overlapping region21Cb of the light-receiving unit10B.

Also, because the lenses18Ac,28Ad, and28Bb, and lenses18Cb,28Cd, and28Bc are lenticular lenses, the lenses18Ac and18Cb condense the light, and parallel beams of light can be formed between the lenses28Ad and28Cd, and the lenses28Bb and28Bc. Therefore, it is possible to further mitigate the decrease in the amount of light received by the light-receiving element group12B of the light-receiving unit10B disposed in the light-receiving element overlapping regions21Ac and21Cb.

Next, a light-receiving unit55A according to Embodiment 3 will be described with reference toFIGS. 9 and 10.

For ease of description, members having the same functions as those in the drawings for Embodiments 1 and 2 are assigned the same reference characters and descriptions thereof will be omitted.

The present embodiment differs from the previous embodiments in that, in a light-receiving unit55A, wiring lines that cross light-receiving element overlapping regions21Ab and21Ac of the light-receiving unit10A are constituted of transparent electrodes, and in that the width of wiring lines that cross the light-receiving element overlapping regions21Ab and21Ac is equal to that of the wiring lines that extend in the Y direction.

FIG. 9is a drawing that shows a configuration of a second terminal forming region16Ac of the light-receiving unit55A.FIG. 10is a drawing that shows a configuration of a first terminal forming region16Ab of the light-receiving unit55A.

Also, wiring lines that bend from the light-receiving element control wiring lines24y1,24y2, . . .24yn-1, and24ynand the light-receiving element output wiring lines25y1,25y2,25y3, . . .25ym-1, and25ym, which extend in the Y direction, and that cross the respective light-receiving element overlapping regions21Ab and21Ac, are similarly made of transparent electrodes made of a material such as ITO, and have a similar width to the light-receiving element control wiring lines24y1,24y2, . . .24yn-1, and24ynand the light-receiving element output wiring lines25y1,25y2,25y3, . . .25ym-1, and25ym, which extend in the Y direction.

By making the wiring lines that cross the respective light-receiving element overlapping regions21Ab and21Ac out of transparent electrodes, it is possible to prevent the wires from blocking light that enters the light-receiving element group12B of the light-receiving unit10B disposed on the rear surface side of the element substrate11A in the light-receiving element overlapping regions21Ab and21Ac, even if the wiring lines crossing the light-receiving element overlapping regions21Ab and21Ac are made wide. Thus, it is possible to reduce the resistance of the wiring lines while preventing a decrease in the sensitivity of the light-receiving element group12B to incident light, thus mitigating a decrease in the amount of light received by the light-receiving element group12B.

Next, a configuration of an optical touch panel device150according to Embodiment 4 will be described with reference toFIG. 11. For ease of description, members having the same functions as those in the drawings for Embodiments 1 to 3 are assigned the same reference characters and descriptions thereof will be omitted.

FIG. 11is a cross-sectional drawing that shows a configuration of the optical touch panel device150according to Embodiment 4.

The optical touch panel device150differs from the optical touch panel device100in that the direction of the light-receiving surface of the light-receiving device differs.

A display panel101is a liquid crystal display panel as in Embodiment 1. The display panel101is provided with at least: a TFT substrate121on which switching elements for driving pixels are formed; a CF substrate122, which is disposed opposite to the TFT substrate121with liquid crystals between the TFT substrate121and the CF substrate122, and has color filters (CF) disposed for each pixel; a rear polarizing plate123disposed on the rear surface of the TFT substrate121; and a front polarizing plate124disposed on the front surface of the CF substrate122. In addition, the front surface of the display panel101is provided with a protective plate125for protecting the display panel101. The display panel101is connected to a driver126for controlling the driving of the display panel101.

The display panel101is stored in a bezel107, which has an opening in a region facing a coordinate input region102of the display panel101. A light source5and a light-receiving device10are also provided in the bezel107. The bezel107is approximately 0.5 mm in thickness.

The light source5is disposed between the protective plate125and an edge part107aof the bezel107on the front surface of the protective plate125. The light source5is made of a plurality of LEDs as stated above, and has a plurality of LEDs aligned on a ceramic substrate127.

The direction that the light source5emits light is different from that of Embodiment 1 in being parallel to the display surface of the display panel101.

In the light-receiving device10, a light-receiving surface12aof a light-receiving element12is disposed so as to be perpendicular to the image display surface of the display panel101and so as to be adjacent to the display panel101. The light-receiving device10is disposed on the rear surface side of the edge part107aof the bezel107and is fixed to a side of the bezel107using a RIM sheet8that is approximately 0.05 mm in thickness.

Light-receiving element groups12A,12B, and12C of the respective light-receiving units10A,10B, and10C of the light-receiving device10are disposed in a line so as to be parallel to the display surface of the display panel101. The respective light-receiving units10A,10B, and10C are disposed such that, of the regions where resin BMs13A,13B, and13C are formed (non-sensor regions), the sides adjacent to the connection pads PAb, PAc, PBb, PBc, PCb, and PCc from the regions where the light-receiving element groups12A,12B, and12C are each aligned in a line come below the front surface of the protective plate125. With this configuration, it is possible to shorten the distance between the protective plate125and the edge part107a. As a result, the difference in height between the opening part of the bezel107and the protective plate125can be minimized, and the edge part107acan be made small.

In this manner, the optical touch panel device150is not provided with a reflective plate or the like, and the light emitted from the light source5enters the light-receiving elements12of the light-receiving device10directly. As a result, the strength of the light entering the light-receiving elements12can be made greater than when the light emitted from the light source5is reflected by a reflective plate and then enters the light-receiving elements12.

The light-receiving device of the present invention needs only to be constituted of a plurality of light-receiving units bonded together, and the number of light-receiving units constituting the light-receiving device is not limited to three; the number of light-receiving units may be two, or four or greater.

The present invention is not limited to the embodiment described above, and various modifications can be made without departing from the scope of the claims. Therefore, embodiments obtained by appropriately combining the techniques disclosed in different embodiments are included in the technical scope of the present invention.

As mentioned above, the light-receiving device of the present invention includes a plurality of light-receiving units, in which each of the plurality of light-receiving units has: a plurality of light-receiving elements; first and second terminal forming regions respectively provided for forming first and second connection terminals for connecting first and second circuits to the plurality of light-receiving elements, respectively; and a light-receiving element forming region disposed between the first and second terminal forming regions, the light-receiving element forming region being provided for forming the plurality of light-receiving elements. Each of the plurality of light-receiving units is provided with a substrate and a protective member, and the plurality of light-receiving elements and the first and second connection terminals are formed on a front surface of the substrate. The protective member is disposed so as to cover the plurality of light-receiving elements, and a rear surface of the first or second terminal forming region in the substrate of one of the light-receiving units and a front surface of the protective member of a light-receiving unit that is different from the aforementioned one of the light-receiving units are bonded together.

According to the above-mentioned configuration, each of the plurality of light-receiving units has first and second terminal forming regions for respectively forming the first and second connection terminals to connect the first and second circuits to the plurality of light-receiving elements, and a light-receiving element forming region, which is disposed between the first and second terminal forming regions, for forming the plurality of light-receiving elements.

With this configuration, the plurality of light-receiving elements are formed on the light-receiving element forming region, and by forming the first connection terminal and the second connection terminal in the first terminal forming region and the second terminal forming region, respectively, it is possible to connect the plurality of light-receiving elements to the first and second circuits. With this configuration, it is possible to control the driving of the light-receiving element groups and control the output from the light-receiving element groups based on the first and second control circuits.

According to the above-mentioned configuration, the protective member is disposed so as to cover the plurality of light-receiving elements formed on the front surface of the substrate, and thus, it is possible to protect the plurality of light-receiving elements.

According to the above-mentioned configuration, the rear surface of the first or second terminal forming region in the substrate of the light-receiving unit and the front surface of the protective member of a different light-receiving unit are bonded together. Also, the first and second terminal forming regions are disposed with the light-receiving element forming region therebetween.

With this configuration, it is possible to dispose the respective light-receiving element forming regions so as to be adjacent when viewing the plurality of light-receiving units bonded to each other from a plan view, and thus, it is possible to dispose the plurality of light-receiving elements formed thereon so as to be adjacent to each other. With this configuration, it is possible to dispose the plurality of light-receiving elements so as to be continuous over a long distance.

Since the plurality of light-receiving units are bonded together, it is possible to mitigate a decrease in yield compared to when the same number of light-receiving elements are formed without bonding the light-receiving elements to each other, even if the number of light-receiving elements formed increases as a result of disposing the light-receiving elements continuously over a long distance.

According to the above-mentioned configuration, a plurality of light-receiving units are provided, and light-receiving element groups are formed in the respective plurality of light-receiving units. With this configuration, it is possible to mitigate a decrease in yield and configure a light-receiving device with light-receiving elements formed at a high density by forming light-receiving elements on each of the plurality of light-receiving units at a high density and bonding together the light-receiving units on which the light-receiving elements are formed at a high density.

Because it is possible to dispose the light-receiving elements at a high density in this manner, it is possible to mitigate a decrease in resolution, even without providing a member such as a lens to cover light-receiving surfaces of all light-receiving elements, for example. As a result, it is possible to mitigate an increase in manufacturing cost compared to when a member such as a lens is disposed to cover the light-receiving surfaces of all light-receiving elements.

The plurality of light-receiving elements are preferably aligned in the light-receiving element forming region. With the above-mentioned configuration, light that enters the light-receiving element forming region can be received by each of the plurality of light-receiving elements.

It is preferable that the plurality of light-receiving units include a first light-receiving unit and a second light-receiving unit, the first light-receiving unit having a rear surface of the substrate in the second terminal forming region bonded to another light-receiving unit, the second light-receiving unit having a front surface of the protective member bonded to the first light-receiving unit, and that the first light-receiving unit and the second light-receiving unit be bonded together such that the plurality of light-receiving elements disposed on the first light-receiving unit and the plurality of light-receiving elements disposed on the second light-receiving unit are in a line with a regular gap from a plan view.

According to the above-mentioned configuration it is possible to dispose a plurality of light-receiving elements continuously over a long distance.

It is preferable that each of the first and second terminal forming regions of the first light-receiving unit be provided with a light-receiving element overlapping region that is adjacent to the first or second connection terminal formed therein and that overlaps some of the plurality of light-receiving elements of the second light-receiving unit, and that some of the plurality of light-receiving elements of the second light-receiving unit are disposed in the light-receiving element overlapping region so as to overlap the region.

According to the above-mentioned configuration, it is possible to dispose some of the plurality of light-receiving elements of the second light-receiving unit so as not to overlap the first or second connection terminal of the first light-receiving unit because some of the plurality of light-receiving elements of the second light-receiving unit overlap the light-receiving element overlapping region that is disposed adjacent to the first or second connection terminal of the first light-receiving unit. With this configuration, it is possible to increase the amount of light received by the light-receiving elements of the second light-receiving unit disposed in the light-receiving element overlapping region of the first light-receiving unit.

It is preferable that horizontal direction wiring lines extending from the first or second connection terminal that is formed and crossing the light-receiving element overlapping region, and vertical direction wiring lines extending from the horizontal direction wiring lines in the direction in which the light-receiving elements of the second light-receiving unit are aligned in the light-receiving element forming region be disposed in each of the first and second terminal forming regions of the first light-receiving unit, and that the horizontal direction wiring lines be thinner than the vertical direction wiring lines.

According to the above-mentioned configuration, it is possible to reduce the amount of light blocked from entering the light-receiving elements of the second light-receiving unit disposed in the light-receiving element overlapping region of the first light-receiving unit as a result of the horizontal direction wiring lines disposed crossing the light-receiving element forming region. As a result, it is possible to mitigate a decrease in the amount of light received by the light-receiving element of the second light-receiving unit disposed in the light-receiving element overlapping region of the first light-receiving unit.

It is preferable that horizontal direction wiring lines crossing the light-receiving element overlapping region and extending from the first or second connection terminal that is formed be disposed in each of the first and second terminal forming regions of the first light-receiving unit, and that the horizontal direction wiring lines be made of a transparent material.

According to the above-mentioned configuration, it is possible to reduce the amount of light blocked by the horizontal direction wiring lines, and thus, it is possible to mitigate a decrease in the amount of light received by the light-receiving elements of the second light-receiving unit disposed in the light-receiving element overlapping region of the first light-receiving unit.

It is preferable that a first lens be disposed on the front surface of the substrate of the first light-receiving unit in the light-receiving element overlapping region of the first light-receiving unit. According to the above-mentioned configuration, light can be condensed using the first lens, and thus, it is possible to mitigate a decrease in the amount of light received by the light-receiving elements of the second light-receiving unit disposed in the light-receiving element overlapping region of the first light-receiving unit.

It is preferable that that a second lens be disposed on the rear surface of the substrate in the light-receiving element overlapping region of the substrate of the first light-receiving unit, and that a third lens be additionally disposed on the front surface of the protective member of the second light-receiving unit, in the region facing the second lens.

According to the above-mentioned configuration, light can be condensed and refracted using the first lenses, the second lenses, and the third lenses, thus mitigating a decrease in the amount of light received by the light-receiving elements of the second light-receiving unit disposed in the light-receiving element overlapping region of the first light-receiving unit.

It is preferable that the first lens, the second lens, and the third lens be lenticular lenses. According to the above-mentioned configuration, the light can be condensed by the first lens, and parallel beams of light can be formed between the second lens and the third lens, and thus, it is possible to further mitigate a decrease in the amount of light received by the light-receiving elements of the second light-receiving unit disposed in the light-receiving element overlapping region.

It is preferable that the rear surface of the second terminal forming region of the substrate of the first light-receiving unit and the front surface of the protective member of the second light-receiving unit be bonded together, and that a third light-receiving unit that is one of the plurality of light-receiving units be additionally provided, and the rear surface of the first terminal forming region of the substrate of the third light-receiving unit and the front surface of the protective member of the second light-receiving unit be bonded together.

According to the above-mentioned configuration, by providing the third light-receiving unit, it is possible to configure a light-receiving device in which light-receiving elements are disposed continuously over an even longer distance.

The optical touch panel device of the present invention includes the above-mentioned light-receiving device, a light source that emits light that enters the light-receiving device, and a display panel that displays images.

According to the above-mentioned configuration, light-receiving element groups are formed on respective light-receiving units bonded together, thus mitigating a decrease in yield and allowing the position to be detected at a high resolution.

Also, because the light-receiving elements are disposed in the light-receiving device continuously over a long distance, it is possible to expand the position input region.

It is preferable that light-receiving surfaces of the plurality of light-receiving elements of the light-receiving device be disposed so as to be parallel to an image display surface of the display panel, that the direction that the light from the light source is emitted be perpendicular to the image display surface of the display panel, and that the optical touch panel device include a light-receiving side reflective plate that covers the light-receiving surface and a light-receiving side reflective plate that covers the light-emitting surface.

According to the above-mentioned configuration, the light emitted from the light source can be received by the light-receiving elements of the light-receiving device by reflecting the light with the light-emitting side reflective plate and the light-receiving side reflective plate. It is possible to configure the optical touch panel device with this configuration.

It is preferable that the direction in which light is emitted from the light source be parallel to the image display surface of the display panel, and that the light-receiving surfaces of the plurality of light-receiving elements of the light-receiving device be disposed so as to be perpendicular to the image display surface of the display panel.

According to the above-mentioned configuration, the light emitted from the light source enters the light-receiving elements directly, and thus, it is possible to increase the strength of the light entering the light-receiving elements.

INDUSTRIAL APPLICABILITY

In the present invention, light-receiving elements are disposed at a high resolution and continuously over a long distance, and thus, the present invention is applicable as a touch panel that requires input positions to be detected accurately, and in particular, the present invention can be appropriately applied as a large touch panel with a large position input area.

DESCRIPTION OF REFERENCE CHARACTERS