JP2016151988A - Input system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the accuracy in detecting a detection target body in the vicinity of a light extraction part on a display surface of a display part, and increase the accuracy in detecting a detection target body at a corner of the display surface distant from the light extraction part.SOLUTION: In plan view, a transparent light guide plate (1) includes a large width part (5) that is a part having a larger width than that of a display surface along a long side, and notches (1a) are provided in the large width part (5).SELECTED DRAWING: Figure 1

Description

  The present invention relates to an input system including an input device that detects position coordinates of an object to be detected.

  Optical coordinate input device or position detection device, and coordinate input device or position detection device including a light guide member that receives coordinate input by a stick-shaped operation member (hereinafter referred to as “pen”) such as a touch pen and a stylus pen An input system such as a tablet or a touch panel in which a display panel and a display panel are combined is known.

  In the input system, the coordinate input device or the position detection device obtains the coordinates of the approached or touched position of the pen by bringing the pen close to or in contact with the coordinate input region of the coordinate input device. The obtained coordinates are displayed as an object such as a point image or a straight line image on a display screen such as a liquid crystal display separate from the coordinate input device or a liquid crystal display panel laminated integrally with the coordinate input device. For use.

  As the optical coordinate input device, there is known a touch pen having a light emitting unit, a light guide member, and a light receiving unit, which detects input coordinates from the direction of light propagating through the light guide member.

  FIG. 13 is a perspective view showing the configuration of the input system of Patent Document 1. As shown in FIG.

  An input system 150 disclosed in Patent Document 1 includes a liquid crystal display panel 102, a light guide member 101 that is disposed on the display surface side of the liquid crystal display panel 102 and has a notch 101 a at an end, a pen 103, and a pen Two imaging units 110 and 120 that detect propagating light that enters the light guide member 101 from 103 and propagates inside the light guide member 101 are provided. The light propagating through the light guide member 101 is reflected by the notch 101a and enters the detection means 110 and 120. The imaging units 110 and 120 detect the traveling direction of the propagation light, and the pen 103 is guided. The position coordinates of the point in contact with the optical member 101 are detected.

JP2013-149231A (released on August 1, 2013)

  However, the optical input system of Patent Document 1 has low detection accuracy with respect to input from the vicinity of the notch 101a. For this reason, when the distance between the notch 101a serving as the light extraction portion for extracting the propagation light from the light guide member 101 and the liquid crystal display panel 102 is short, the object in the vicinity of the light extraction portion on the display surface of the liquid crystal display panel 102 is used. There exists a subject that the detection accuracy of a detection body becomes low.

  In order to avoid this problem, it is conceivable to provide a sufficient distance between the liquid crystal display panel and the light extraction unit.

  However, in this case, the light guide member needs to be enlarged, and the entire input device is enlarged. In addition, there is a problem that the size of the liquid crystal display panel and the light guide member are not equal and the frame becomes large.

  Furthermore, for light incident from a position away from the light extraction part, loss occurs while propagating inside the light guide member, and the amount of light reaching the light receiving part is weakened. There has been a problem that it is difficult to detect the detection object at the corner of the surface.

  The present invention has been made in view of the above problems, and its object is to improve the detection accuracy of the detection object in the vicinity of the light extraction unit on the display surface of the display unit and to move away from the light extraction unit. An object of the present invention is to provide an input system in which detection accuracy of a detection object at a corner of a display surface is increased.

  In order to solve the above problems, an input system according to one embodiment of the present invention includes a display portion having a display surface, and a rectangular light guide provided to face the display surface and having a long side and a short side. A light extraction unit for extracting the light emitted from the member to be detected and propagating through the light guide member to the outside of the light guide member, and the light extracted by the light extraction unit, And a detection unit that detects a position of the detected object on the surface of the light guide member, wherein the light guide member is at least one longer side than the display surface in plan view. A widened portion which is a wide portion is provided, and the light extraction portion is provided in the widened portion.

  According to one embodiment of the present invention, the detection accuracy of a detection object in the vicinity of the light extraction unit on the display surface of the display unit is improved, and the detection of the detection object in the corner of the display surface far from the light extraction unit is detected. An input system with high accuracy can be provided.

(A) is a perspective view which shows the structure of the input system of one Embodiment of this invention, (b) is the top view (plan view). It is arrow sectional drawing of cutting line AA 'shown in FIG. It is a figure which shows the structure of the pen of the input system of one Embodiment of this invention. It is a figure of the acquired image acquired in the image sensor with which the pen input device of the input system of one embodiment of the present invention was equipped. It is a figure which shows the propagation loss of the light in the input system of one Embodiment of this invention. It is a top view (top view) which shows the structure of the input system of other embodiment of this invention. It is a perspective view which shows the structure of a part of input system of other embodiment of this invention. It is sectional drawing which shows the one part schematic structure of the input system of other embodiment of this invention. It is a perspective view of a structure of the optical member of the input system of other embodiment of this invention. It is a perspective view which shows the one part schematic structure of the input system of other embodiment of this invention. It is a top view (plan view) showing a modification of the configuration shown in FIG. It is a top view which shows the distance between the light extraction part and the corner | angular of a liquid crystal display panel in planar view. FIG. 11 is a perspective view illustrating a configuration of an input system disclosed in Patent Document 1.

  An embodiment of an input device according to the present invention will be described in detail with reference to the drawings. The input device and input system of the present invention are applied to tablets, touch panels, and the like. In addition, the following embodiment is only an example in which the present invention is embodied, and it is needless to say that the embodiment can be appropriately changed without departing from the gist of the present invention.

Embodiment 1
An embodiment of an input system according to the present invention will be described with reference to FIGS.

  Fig.1 (a) is a perspective view which shows the structure of the input system of this embodiment, FIG.1 (b) is the top view (plan view). 2 is a cross-sectional view taken along line AA ′ shown in FIG.

<Configuration of input system 50>
As shown in FIG. 1A, the input system 50 of the present embodiment includes a pen input device 40 (coordinate input device), a pen 3 (operation member), and a liquid crystal display panel 2 (image display panel, display unit). When the pen 3 touches (contacts) the touch surface (upper surface) which is the surface of the pen input device 40, the touch position coordinates on the touch surface can be obtained.

<Pen input device 40>
As shown in FIG. 1A, the pen input device 40 is a quadrangular (rectangular) transparent light guide plate disposed on the liquid crystal display panel 2 so as to face the display surface of the liquid crystal display panel 2. 1 (light guide member) and imaging units 10 and 20 (detection units) disposed near both ends of a certain side of the transparent light guide plate 1.

  The liquid crystal display panel 2 has a liquid crystal layer sandwiched between a pair of substrates (not shown), and each substrate is provided with at least various electrodes for changing the orientation of liquid crystal molecules of the liquid crystal layer by applying a voltage. Then, by changing the orientation of the liquid crystal molecules by applying a voltage, the amount of light transmitted through the liquid crystal layer of each pixel is adjusted to perform a desired display. As the configuration of the liquid crystal display panel 2, a conventionally known liquid crystal display panel can be used. In general, a known liquid crystal display panel is often a rectangle having a ratio of 4: 3 or 16: 9 (the lengths of two opposing sides are different). Use panels.

  The transparent light guide plate 1 is made of a single flat plate made of a translucent material, and is disposed so as to overlap the display surface side of the liquid crystal display panel 2. The size of the transparent light guide plate 1 can be configured to be substantially the same as that of the liquid crystal display panel 2. In the present embodiment, as shown in FIG. 1B, the transparent light guide plate 1 includes a widened portion 5 that is a portion wider than the display surface of the liquid crystal display panel 2 along one long side.

  Thereby, at least a part of the imaging units 10 and 20 can be disposed on the back side of the widened portion 5 of the transparent light guide plate 1. In this case, although the details of the reason will be described later, it is preferable that the distance between the imaging units 10 and 20 and the liquid crystal display panel is longer as the thickness of the transparent light guide plate 1 is thicker. In the case of 2 mm, the imaging units 10 and 20 are preferably separated from the liquid crystal display panel by 50 mm or more. As a result, the touch position can be detected with high accuracy even in the vicinity of the imaging units 10 and 20. Furthermore, the imaging units 10 and 20 are disposed in the vicinity of both ends of one long side inside the extended lines B and B ′ obtained by extending the diagonal lines of the liquid crystal display panel. This shortens the distance between the imaging unit 10 and the corner (E2) of the liquid crystal display panel farthest therefrom, and the distance between the imaging unit 20 and the corner (E1) of the liquid crystal display panel farthest therefrom. Can do. As a result, the touch position can be detected with high accuracy even in a portion away from the imaging unit. Furthermore, the enlargement of the size of the transparent light guide plate 1 in the pen input device 40 in the direction extending along the touch surface is suppressed, which contributes to the realization of the compact size of the pen input device 40.

  The surface of the transparent light guide plate 1 opposite to the liquid crystal display panel 2 is a touch surface that is touched by the pen 3.

  In addition, concave conical cutouts 1a (optical path conversion unit and light extraction unit) are formed at two corners of the transparent light guide plate 1 where the imaging units 10 and 20 are disposed. In a plan view (when the upper surface of the transparent light guide plate 1 is viewed from above the transparent light guide plate 1), the two notches 1 a are provided at both ends of the widened portion 5 of the transparent light guide plate 1.

  The angle (γ shown in FIG. 2) formed by the conical surface of the notch 1a and the back surface of the transparent light guide plate 1 is 45 degrees or less, and 30 degrees or 45 degrees is selected. A mirror coating 6 is applied to the conical cutout 1a. As a result, as shown in FIG. 2, the optical path of the light propagating through the inside of the transparent light guide plate 1 and reaching the notch 1a is formed below the transparent light guide plate 1 by the notch 1a, that is, on the back surface of the transparent light guide plate 1. Change towards. That is, the notch 1a functions as a light extraction unit for extracting light propagated through the transparent light guide plate 1 to the outside.

  Even without the mirror coating 6, the optical path can be changed below the transparent light guide plate 1 by the conical surface of the notch 1 a. In this case, the angle formed by the conical surface and the back surface of the transparent light guide plate 1 is selected to be 20 degrees or 30 degrees. At this time, a part of the light reaching the notch 1a is totally reflected by the conical surface, so that the optical path is converted. (Light that does not satisfy the total reflection condition at the conical surface is refracted and passes through the conical surface and does not reach the imaging unit.) The transparent light guide plate 1 does not have to be a perfect quadrangle, and the corners are cut off. It may be a substantially quadrangular shape such as being missing or having a curved corner.

  In this embodiment, since the optical path conversion part is provided as the notch 1a of the transparent light guide plate 1, the optical path conversion part can be avoided from protruding from the transparent light guide plate 1.

  The thickness of the transparent light guide plate 1 is mainly 1 to 3 mm. However, it may be thicker than this. In the present embodiment, the thickness is, for example, 2 mm. The size of the quadrilateral of the transparent light guide plate 1 can be, for example, about 1000 mm × 750 mm, but is not limited thereto. Moreover, as a material of the transparent light-guide plate 1, an acrylic is used, for example, and a polycarbonate and glass may be sufficient. Any material can be used as long as light can propagate inside. In addition, it is preferable that it is a material with a high transmittance | permeability, so that the magnitude | size of the transparent light-guide plate 1 becomes large. This is because the light from the pen 3 (touch pen, light-emitting pen) can efficiently reach the imaging units 10 and 20. In this embodiment, for example, the material is acrylic. Acrylic is preferable because it is easy to process the notch 1a, has a high transmittance, and can be obtained at a relatively low price even if the size is large.

  The imaging units 10 and 20 are means for detecting propagation light that enters the transparent light guide plate 1 from the light emitting unit 30 of the pen 3 and propagates through the inside of the transparent light guide plate 1. It arrange | positions directly under the notch 1a. That is, the imaging units 10 and 20 are disposed at two locations that are separated from each other. In addition, the imaging units 10 and 20 do not protrude above the touch surface of the transparent light guide plate 1. The imaging unit 10 includes a lens 11, a visible light cut filter 12, and an imaging element 13. Similarly, the imaging unit 20 includes a lens 21, a visible light cut filter 22, and an imaging element 23. The light receiving surfaces of the image sensors 13 and 23 are disposed so as to be parallel to the surface of the transparent light guide plate 1. The image sensors 13 and 23 are two-dimensional image sensors. The imaging units 10 and 20 are connected to the transparent light guide plate 1 and have a structure in which light that does not propagate through the transparent light guide plate 1 is not coupled to the imaging elements 13 and 23.

  In the present embodiment, the notch 1a is configured in a conical surface shape, but the present invention is not limited to this and may be configured in a polygonal surface shape.

<Pen 3>
On the other hand, the pen 3 corresponding to the pen input device 40 is an operation member called a touch pen or a stylus pen. Details of the pen 3 will be described with reference to FIG.

  FIG. 3 is a diagram showing the configuration of the pen 3. For convenience of explanation, a part of the housing is removed to expose the internal structure. The pen 3 has a light emitting unit 30 that has a light emitting element 31 that emits infrared light and a light guide member 32 that guides the infrared light to the tip of the pen 3, and a power supply device 33. And the control device 34 are stored. As a configuration of the pen 3 of the present embodiment, the light emitting unit 30 is disposed at the tip of the pen 3 and a light diffusion member 36 that diffuses light is attached to the light emitting side of the light emitting unit 30. There is a point.

  The light diffusing member 36 is made of a resin containing a light diffusing material. Glass beads can be used as the light diffusion material. As the resin, a fluororesin (specifically, polytetrafluoroethylene) and silicon rubber can be used, and it is preferable that the resin is configured to have elasticity. By using the elastic material, when using the transparent light guide plate 1 of the pen input device 40 in contact with the tip of the pen 3, that is, the light diffusing member 36, the surface of the transparent light guide plate 1 is not damaged and is slightly touched by the contact. Since the contact portion is deformed to increase the contact area with the surface of the transparent light guide plate 1, the amount of light coupled to the surface of the transparent light guide plate 1 can be increased. That is, the light from the pen 3 can be incident in a plurality of radial directions with respect to the depth direction inside the transparent light guide plate 1. However, the present invention is not limited to this, and may be other modes.

  As the light emitting element 31, for example, an LED (light emitting diode) or an LD (laser diode) emitting light such as infrared light can be used. The number of LEDs or LDs is not limited to one provided for one pen 3, and a plurality of LEDs or LDs may be mounted.

  Infrared light from the light emitting element 31 that receives light from the power supply device 33 and enters the light diffusing member 36 through the light guiding member 32 enters the light diffusing material 36 and the fine light. Diffusely reflected by unevenness. And it is radiate | emitted as diffused light from the light-projection surface of the light-diffusion member 36. FIG.

  The power supply device 33 can be configured to include a battery, for example, or may be configured to be rechargeable.

  The control device 34 controls the light emission of the light emitting element 31. For example, a mechanism for emitting light only when the light emitting element 31 comes into contact with the transparent light guide plate 1 is included. This mechanism is configured by using a pressure-sensitive switch or the like, and can control the light emission time, thereby reducing power consumption and extending battery life.

  As described above, the pen 3 is provided with the light source (light emitting unit 30) that emits infrared light, and the infrared light is diffused and emitted from the pen tip. When the pen tip of the pen 3 comes into contact with the transparent light guide plate 1, part of the infrared light emitted from the pen tip is coupled to the transparent light guide plate 1 and propagates through the transparent light guide plate 1. Since the pen 3 diffuses and emits infrared light from the pen tip, the light coupled to the transparent light guide plate 1 is guided and propagated through the transparent light guide plate 1 while diffusing and radiating.

  Infrared light propagating through the transparent light guide plate 1 (hereinafter referred to as propagation light 4a and 4b) enters the imaging units 10 and 20 through the notches 1a. In the imaging units 10 and 20, an angle formed with the imaging units 10 and 20 in the two-dimensional plane of the transparent light guide plate 1 at a location where the pen 3 is in contact is obtained from each image obtained from the imaging element 13. Thereby, the position coordinates of the contact in the two-dimensional plane can be obtained with high accuracy. Hereinafter, the detection principle of pen input will be described in detail.

<Pen input detection principle>
A method of calculating pen input coordinates in the present embodiment will be described below with reference to FIGS. 1, 2, 4, and 5. FIG.

When the pen tip of the pen 3 contacts the touch surface (transparent light guide plate surface) of the pen input device, as shown in FIG. 2, a part of the infrared light emitted from the pen 3 is a transparent light guide plate having a refractive index N 1 is incident. Of this incident light, the propagation angle θP in the transparent light guide plate 1 is expressed by the formula:
sin (90 ° −θP)> 1 / N
2 is confined in the transparent light guide plate 1 and repeatedly reflected on the front and back surfaces of the transparent light guide plate 1 and travels through the transparent light guide plate 1 as shown in FIG.

  Here, as shown in FIG. 1, the infrared light emitted from the pen 3 is diffused radially with respect to the two-dimensional plane of the transparent light guide plate 1 around the pen tip and propagates in the transparent light guide plate 1. A part of the propagation light of the luminous flux is guided to the end face of the conical cutout 1a, and the reflected light of the end face is received by the imaging units 10 and 20. Specifically, the reflected light of the notch 1 a is collected by the lenses 11 and 21, subsequently passes through the visible light cut filters 12 and 22, and is finally received by the imaging elements 13 and 23. The visible light cut filters 12 and 22 transmit infrared light emitted from the pen 3 and play a role of blocking light in other wavelength bands. The visible light cut filters 12 and 22 block stray light such as sunlight and liquid crystal display panel backlight light, and can increase the SN ratio. In this embodiment, it is assumed that infrared light is emitted from the pen 3 and the visible light cut filters 12 and 22 cut infrared light. However, the present invention is not limited to this, and the pen 3 is not limited thereto. A filter that transmits visible light in the wavelength band of visible light emitted from the pen 3 and blocks light in other wavelength bands (for example, a bandpass). Filter) can also be used.

  As shown in FIG. 4A, the light emitted from the pen 3 and propagated through the transparent light guide plate 1 passes through the lens 11 to form a linear image 15 on the image sensor 13. The position of the linear image 15 changes depending on the position of the pen 3, and by analyzing the acquired image of the imaging unit, the angle α formed between the light beams 4a and 4b shown in FIG. , Β are respectively obtained, and the position coordinates of the point where the pen tip serving as the light source contacts is obtained by using the principle of triangulation. In FIG. 4A, when the pen is at the position 3a, a linear image 15 is formed. When the pen moves to the position 3b, a linear image 17 is formed.

  FIG. 4B shows an acquired image of the image sensor 13. When the pen tip of the pen 3 in the state of irradiating infrared rays is not in contact with the transparent light guide plate 1, nothing appears in the acquired image of the image sensor 13. On the other hand, when the pen tip of the pen 3 in the state of irradiating infrared rays from the light emitting unit comes into contact with the transparent light guide plate 1 and the infrared light is coupled to the transparent light guide plate 1, as shown in FIG. A part of the light beam 4a is guided to the imaging device 13, a linear image is formed on the imaging surface of the imaging device 13, and the linear image 15 appears on the acquired image.

  The position of the linear image 15 shown in FIG. 4B changes depending on the position of the contact point of the pen tip of the pen 3, and when the position of the contact point of the pen tip is changed, the linear image is a broken line. It changes like the linear image 17 shown. The locus of the linear image is a fan shape 16 indicated by a one-dot chain line. The rotation angle α1 ′ (with the center of the arc as the center of rotation) connecting the fan-shaped center 18 and the line image is the line connecting the pen 3 and the image sensor 13 and the certain side of the transparent light guide plate 1. The angle α1 is the same as the angle α1. Α1 ′ is obtained from the acquired image of the image sensor, and α1 is obtained from α1 ′. Similarly, when the pen moves to the position 3b, a linear image 17 is formed, and α2 ′ is obtained by obtaining the inclination α2 ′ of the linear image 17.

Similarly, for the image sensor 23, the position of the light emitting point is specified from the analysis of the acquired image, and the angle β formed by the line segment connecting the pen 3 and the image sensor 23 and the certain side of the transparent light guide plate 1 is obtained.
Then, when the interval between the image sensors is L, the displacement angle of the bright spot obtained by reading the image from the image sensor 13 is α, and the displacement angle of the bright spot obtained by reading the acquired image from the image sensor 23 is β, The coordinates (X, Y) of the bright spot are the following relational expressions (1) and (2);
Y = tan α · X (1)
Y = tan β · (L−X) (2)
Satisfied. Solving this, the coordinates (X, Y) of the bright spot are
X = tan β · L / (tan α + tan β) (3)
Y = (tan α · tan β) · L / (tan α + tan β) (4)
The coordinates X and Y of the point where the pen tip contacts are obtained by α and β obtained as described above and L that can be obtained in advance. Among these, L is an interval between the image sensor 13 and the image sensor 23 and is a fixed value. By obtaining α and β, pen input coordinates X and Y (position coordinates) can be obtained.

  Note that the distance L between the imaging elements is a distance between the optical axis center of the lens 11 and the optical axis center of the lens 21.

  In order to obtain the position coordinates of the pen 3 by the above method, the input system 50 is provided with a position coordinate detection unit (not shown). The position coordinate detection unit can be provided in the pen input device 40.

  Further, based on the position coordinates of the pen 3 obtained by the above method, the pixel at the position corresponding to the position coordinates of the liquid crystal display panel 2 is driven, and the user visually recognizes the touch position of the pen 3. Is possible. For this purpose, if a control unit (not shown) that controls the driving of the liquid crystal display panel 2 acquires information on the position coordinates obtained by the position coordinate detection unit and drives the liquid crystal display panel 2 based on the information. Good.

<Problems of the prior art and their solutions>
Here, when the contact point on the transparent light guide plate 1 of the pen 3 is in the vicinity of the notch 1a and the associated imaging units 10 and 20 (particularly within 40 mm), the linear shape obtained by the imaging elements 13 and 23 is obtained. The image does not become a single continuous line as shown in 15 and 17 of FIG. 4B, but becomes a thick line as shown in 19 of FIG. 4C or a dotted line as shown in FIG. There is a case. This is a phenomenon that occurs because the distance between the pen 3 and the notch 1a is short, and can be interpreted as follows.

  First, the thick line image (19) is obtained for the following reason. When the pen 3 is far from the notch 1a, the light that reaches the notch 1a forms an image on the imaging elements 13 and 23 along the linear propagation paths (light beams 4a and 4b) shown in FIG. The light that mainly goes through is mainly, and the light that reaches the periphery of the conical surface of the other notch 1a is refracted by the conical surface and does not enter the lenses 11 and 21. As a result, a linear image (thin) is obtained on the image sensor (an image with a narrow angle of view). On the other hand, when the pen 3 is in the immediate vicinity of the notch 1a, the light reaching the notch 1a is incident on the lenses 11 and 21 not only on the straight propagation path (light beams 4a and 4b) but also in the vicinity thereof. The image is formed on the image sensors 13 and 23. As a result, a thick linear image is obtained on the image sensor (an image with a wide angle of view).

  Next, the reason why the dotted image (20) is obtained will be described. When the distance between the pen 3 and the notch 1a is short, the light that forms an image on the imaging elements 13 and 23 through the notch 1a out of the light that has entered the transparent light guide plate 1 from the pen 3 is reflected on the transparent light guide plate 1. Most of the light is not internally reflected once on the surface on the liquid crystal display panel side, or light is internally reflected only once or twice. That is, the notch 1a is reached in a state where the propagation distance is short and light is not sufficiently dispersed (mixed). As a result, the images appearing on the image sensors 13 and 23 are considered to be dotted lines.

  As described above, when the image obtained by the image sensor 13 or 23 becomes thick or dotted, it becomes difficult to correctly acquire the inclination α1 or α2 of the linear image, and as a result, the position detection accuracy of the pen 3 is improved. It will cause a decline. For this reason, it is desirable that the distance from the position range in which the position of the pen 3 needs to be detected to the notch 1a is separated by a certain distance, more preferably 50 mm or more. In general, the position range in which the position of the pen 3 is desired to be detected is the same size as the liquid crystal display panel 2, so one side where the image pickup unit of the liquid crystal display panel 2 is disposed and the image pickup unit (notch 1 a associated therewith) The distance is preferably 50 mm or more.

  On the other hand, when detecting a position far from the image sensor 13 or 23, particularly the position of the pen 3 at the corner E1 or E2 of the farthest liquid crystal display panel 2, a sufficient amount of light is caused by the loss in propagation. May not reach 23. That is, the light incident on the transparent light guide plate 1 from the pen 3 at the position E1 is propagated, for example, in the present embodiment over a diagonal line (1250 mm) or more of the liquid crystal display panel 2 while repeating internal reflection. During this time, light is gradually weakened due to loss due to repeated internal reflection and absorption by the transparent light guide plate, and the light that reaches the image sensor 23 becomes weak light. Then, the position of the pen 3 cannot be detected with high accuracy.

  In order to solve these problems, in this embodiment, the notch 1a and the imaging units 10 and 20 associated therewith are provided such that the longer side of the liquid crystal display panel 2 is longer than the diagonal extensions B and B ′ of the liquid crystal display panel 2. It is provided near. In other words, the notch 1 a is provided in the widened portion 5 of the transparent light guide plate 1.

  Hereinafter, the distance between the notch and the corner of the display surface of the liquid crystal display panel 2 will be described with reference to FIG. FIG. 12 is a plan view showing the distance between the notch and the corner of the liquid crystal display panel in plan view.

  In the conventional input device, a notch 1c is provided on diagonally extending lines B and B ′ of the display surface of the liquid crystal display panel 2. At this time, the distance between the notch 1c and the corners E1 and E2 of the display surface of the liquid crystal display panel 2 in plan view is represented by the length of the line segment 2c.

  On the other hand, in the pen input device 40 according to the present embodiment, the notches 1 a are formed at both ends of the widened portion 5 provided along the long side of the transparent light guide plate 1. At this time, the distance between the notch 1a and the corners E1 and E2 of the display surface of the liquid crystal display panel 2 is represented by the length of the line segment 2a.

  As shown in FIG. 12, when the position of the notch 1a is a position translated from the position of the notch 1c along the long side of the transparent light guide plate 1, the line segment 2a is shorter than the line segment 2c. Therefore, according to the pen input device 40 of this embodiment, compared with the conventional input device, from the part facing the corners E1 and E2 of the display surface in the transparent light guide plate 1, the imaging unit 10. It is possible to suppress the loss of light in the path to reach 20 and improve the detection sensitivity.

  In addition, in order to provide sufficient distance between a liquid crystal display panel and a notch, as shown in FIG. 12, the short side widening part provided along the short side of the transparent light-guide plate 101 (light guide member) When the notch 1b is provided in 105, the distance between the notch 1b and the corners E1 and E2 of the display surface of the liquid crystal display panel 2 is represented by the length of the line segment 2b. Here, the line segment 2a is shorter than the line segment 2b.

  Therefore, the notch 1a is provided in the widened portion 5 provided along the long side of the transparent light guide plate 1 as in the pen input device 40 of the present embodiment, thereby providing the short side of the transparent light guide plate 101. The distance between the notch and the corners E1 and E2 of the display surface of the liquid crystal display panel 2 can be shortened as compared with the case where the notch 1b is provided in the widened portion 5b. As a result, the loss of light in the path from the portion of the transparent light guide plate 1 facing the corners E1 and E2 of the display surface to the imaging units 10 and 20 via the notch 1a is suppressed, and the detection sensitivity is improved. can do.

  For example, FIG. 5 shows the relationship between the propagation distance (the distance from the pen input position to the notch) and the intensity of light reaching the image sensor. This is an experimental value in the case of using a transparent light guide plate having a thickness of 5 mm made of glass and a pen having an emission wavelength of 730 nm. FIG. 5 shows that the intensity of light reaching the image sensor decreases as the propagation distance increases. For example, when the propagation distance is shortened by 50 mm from 650 mm to 600 mm, the intensity of light reaching the image sensor is improved by approximately 1.3 times. That is, the liquid crystal display panel is provided by disposing the imaging units on the long side from the diagonal line as in the present embodiment rather than disposing the imaging units at both ends of a certain side of the liquid crystal display panel 2 as in the prior art. The propagation loss of the propagation light from the two corners E1 and E2 can be suppressed, and as a result, the accuracy of position detection can be improved.

  Therefore, as in the present embodiment, the imaging unit is preferably provided closer to the longer side of the liquid crystal display panel 2 than the diagonal extensions B and B ′ of the liquid crystal display panel 2.

  Further, by arranging the imaging unit as in the present embodiment, the size of the transparent light guide plate 1 is set to the size of the liquid crystal display panel 2 for the sides other than the long side of the liquid crystal display panel 2 on which the imaging unit is arranged. The size of the transparent light guide plate in the direction of the touch surface can be suppressed, and a narrow frame can be realized.

(Operational effect of this embodiment)
As described above, the input system 50 according to the present embodiment can obtain the position coordinates of the pen 3 by capturing the propagated light at at least two positions apart from each other at the end of the transparent light guide plate 1. That is, the total number of image sensors may be two, that is, the image sensor 13 and the image sensor 23 as shown in FIG. Therefore, it is not necessary to dispose an image sensor in each light guide region, and the apparatus is not complicated and large, and the cost is not increased.

  Moreover, according to said structure, a transparent light-guide plate is one simple board, Complicated light guide body cost does not start.

  Further, according to the configuration of the pen input device 40 of the present embodiment, since the imaging elements 13 and 23 are provided at positions that do not protrude upward from the touch surface of the transparent light guide plate 1, the touch surface of the transparent light guide plate 1 is It becomes the uppermost surface of the pen input device 40, and the image sensor does not protrude above the touch surface. Therefore, even when the pen input device 40 of the input system 50 of this embodiment is applied to a table type terminal, the table surface can be made completely flat without the surroundings rising like a bank.

  In addition, the input system 50 according to the present embodiment is not a light shielding method, but has a configuration in which light that has propagated inside the light guide plate is received by the imaging device, so that there is no possibility of erroneous recognition due to stray light including sunlight. Accurate position detection can be realized, and therefore it is possible to place the device outdoors or near a window.

  Further, the pen input device 40 of the input system 50 according to the present embodiment includes light that does not propagate through the transparent light guide plate 1 because the imaging units 10 and 20 that receive the light emitted from the tip of the pen 3 are connected to the transparent light guide plate 1. Has a structure that is not coupled to the imaging elements 13 and 23. Therefore, even if illumination light is applied from the normal direction of the touch surface of the transparent light guide plate 1, since the light is not coupled to the transparent light guide plate 1, stray light is not guided to the imaging elements 13 and 23. For this reason, the pen input device 40 is not easily affected by external light, and can be disposed outdoors or near a window.

  From the above, the present invention having the above-described configuration provides a highly versatile input system that realizes a full flat coordinate input device and that is not erroneously recognized even if a hand touches the surface of the device. be able to. In addition, signals from the corners of the liquid crystal display panel can be detected with high accuracy. Furthermore, it is possible to realize a narrow frame on the side where no imaging unit is provided.

  In addition, although this embodiment demonstrated the structure using the image pick-up element 13 and the image pick-up element 23 in total, this invention is not limited to this, Each in the edge part of the transparent light-guide plate 1 is not limited to this. You may collect in one image pick-up element using a mirror and a shutter from a part.

  In the present embodiment, the configuration using one pen 3 has been described. However, the present invention is not limited to this, and even when a plurality of pens are used, for example, the light emission timing of each pen is set. If they are different, the position coordinates can be obtained even if a plurality of pens are simultaneously in contact with the touch surface of the transparent light guide plate 1.

  Further, in the present embodiment, the light emitted from the tip of the pen 3 is configured to diffuse by the light diffusion member 36 provided at the tip of the pen 3. Thereby, a sufficient amount of light can be coupled to the transparent light guide plate 1 without depending on the inclination angle of the pen 3. Therefore, accurate position detection can be realized.

[Embodiment 2]
Another embodiment of the present invention will be described. In addition, in this embodiment, in order to demonstrate a difference from the said Embodiment 1, for convenience of explanation, the same member number is attached | subjected to the member which has the same function as the member demonstrated in Embodiment 1, and the description Is omitted.

  The following will describe another embodiment of the present invention with reference to FIG.

  As shown in FIG. 6, the pen input device 41 of the present embodiment is different from the first embodiment in the positions of the notches 1 a provided in the transparent light guide plate 1 and the imaging units 10 and 20 associated therewith.

  The cutouts 1a of the second embodiment are arranged one by one along two opposing long sides of the liquid crystal display panel 2, and their detailed positions are both at the ends of the long sides close to the same short side. In addition, the center of the notch 1a is provided closer to the longer side than the two diagonal lines B and B 'of the liquid crystal display panel 2.

  In other words, the transparent light guide plate 1 includes a widened portion 5a and a widened portion 5b along each of both long sides. And the notch 1a is provided in each wide part 5a * 5b so that it may mutually oppose along the short side of the transparent light-guide plate 1. FIG.

  For example, when the thickness of the transparent light guide plate 1 is 2 mm, it is preferable that the center of the notch 1a is separated from the long side of the liquid crystal display panel by about 50 mm for the reason described above. Thereby, the length of the straight line connecting the center of the notch 1a and the corners E1 ′ and E2 ′ of the liquid crystal display panel farthest from the center becomes the same as in the first embodiment, and the light extracted from the notch 1a. The amount of can also be equivalent. Therefore, the position of the pen 3 can be accurately detected even at a position far from the notch 1a.

  Further, by arranging the notch 1a and the imaging units 10 and 20 as in the second embodiment, the transparent light guide plate 1 of the pen input device 41 expands along the direction in which the long side of the liquid crystal display panel 2 extends. Since the size of the transparent light guide plate 1 protruding to the short side of the liquid crystal display panel 2 can be suppressed, the frame can be narrowed. As a result, the enlargement of the pen input device 41 as a whole can be suppressed.

  Although Embodiments 1 and 2 have the same effect, it is desirable to select a preferable one according to the place and application where the input system 50 and the pen input devices 40 and 41 are installed. For example, when the pen input devices 40 and 41 are embedded in a desk or the like, it may be selected which is preferable according to the size of the desk, the size of the room where the desk is installed, the space, or the like.

[Embodiment 3]
Another embodiment of the present invention will be described. In addition, in this embodiment, in order to demonstrate a difference from the said Embodiment 1, for convenience of explanation, the same member number is attached | subjected to the member which has the same function as the member demonstrated in Embodiment 1, and the description Is omitted.

  The following will describe another embodiment of the present invention with reference to FIGS.

  As shown in FIG. 7, the pen input device 42 of the input system 52 of the present embodiment includes an optical member 90 (optical path conversion unit, light extraction unit) that is closely fixed to the back surface of the transparent light guide plate 1 ′. And the point which differs in the shape of transparent light-guide plate 1 'differs from the pen input device 40 of Embodiment 1. FIG. In the pen input device 42 of the present embodiment, the imaging units 10 and 20 are disposed at positions where light is emitted from the optical member 90.

  In addition, the pen input device 42 of the present embodiment has a part of the propagation light propagating through the transparent light guide plate 1 ′ below the back surface of the transparent light guide plate 1 ′ by the optical member 90 described later from the back surface of the transparent light guide plate 1 ′. Take out. That is, the optical member 90 functions as a light extraction unit for extracting light propagated through the transparent light guide plate 1 ′ to the outside. Therefore, it is not necessary to provide a notch in the light guide plate as in the first embodiment. That is, the transparent light guide plate 1 ′ only needs to have a configuration (structure) capable of propagating light therein, and does not require any other processing.

  The optical member 90 is a translucent material disposed between the back surface of the transparent light guide plate 1 ′ and imaging units 10 and 20 described later.

  8 is a cross-sectional view taken along the line AA ′ shown in FIG. FIG. 9 is a diagram showing the outer shape of the optical member 90. The optical member 90 has a flat upper surface (adjacent surface) and is bonded and fixed to the back surface of the transparent light guide plate 1 ′ as shown in FIG. The optical member 90 takes out the light propagating through the transparent light guide plate 1 ′ from the back surface of the transparent light guide plate 1 ′, makes the extracted light incident on itself, and couples it inside to propagate inside. It is the composition which makes it. The bonding method between the optical member 90 and the transparent light guide plate 1 ′ is not particularly limited. However, as described above, the optical member 90 takes out light from the transparent light guide plate 1 ′ and makes it incident, so this is not hindered. Adhering and fixing using a method or material.

  The optical member 90 is made of a material having the same or higher refractive index than the transparent light guide plate 1 ′. This prevents light propagating through the transparent light guide plate 1 ′ from being reflected at the boundary surface between the optical member 90 and the transparent light guide plate 1 ′ and returning again to the inside of the transparent light guide plate 1 ′. The extraction efficiency of light from ′ can be increased. In this embodiment, since the transparent light guide plate 1 ′ is made of glass, the optical member 90 is made of high refractive index glass or polycarbonate having a higher refractive index than glass. Thereby, it is possible to efficiently extract light from the transparent light guide plate 1 ′ and to enter the optical member 90.

  In addition, as mentioned above, since this invention can comprise a transparent light-guide plate from materials other than glass, when a transparent light-guide plate is an acrylic, for example, an optical member is acrylic, high refractive index glass, polycarbonate similarly. It can consist of

  In this embodiment, the optical member 90 is made of a material having a refractive index higher than that of the transparent light guide plate 1 ′. However, the light propagating through the transparent light guide plate 1 ′ is the optical member 90 and the transparent light guide plate 1. And the optical member 90 may be made of a material having the same refractive index as that of the transparent light guide plate 1 ′. .

  As shown in FIGS. 8 and 9, the optical member 90 is provided with a concave conical cutout 90 a in a region near the corner of the transparent light guide plate 1 ′ on the end surface adjacent to the upper surface. The angle (γ shown in FIG. 8) formed by the conical surface of the notch 90a and the back surface of the optical member 90 is 45 degrees or less, and 30 degrees or 45 degrees is selected. The conical cutout 90a may be provided with a mirror coating (optical path changing portion).

  Then, as shown in FIG. 8, the light propagating through the optical member 90 and reaching the notch 90a changes its optical path toward the lower side of the optical member 90, that is, toward the back surface of the optical member 90 by the notch 90a. Let That is, the light propagating through the transparent light guide plate 1 ′ travels downward from the lower surface of the transparent light guide plate 1 ′.

In the present embodiment, the notch 90a is formed in a conical surface shape, but the present invention is not limited to this, and may be formed in a hyperboloid shape or a polygonal surface shape.
In the present embodiment, the shape of the optical member 90 is a shape similar to a sector as shown in FIG. 9 when viewed from the upper surface side, but is not limited thereto.

  Moreover, the manufacturing method of the optical member 90 is not particularly limited, but can be manufactured at low cost by plastic molding or glass molding.

  As shown in FIG. 7, the optical member 90 is disposed on the back surface in the vicinity of two adjacent corners of the four corners of the rectangular transparent light guide plate 1 ′. More specifically, the optical member 90 is provided at both ends of the widened portion of the transparent light guide plate 1 ′. The arrangement position of the optical member 90 is not limited to this. Since the two imaging units 10 and 20 are arranged apart from each other in order to realize a detection method described later, the light is propagated through the transparent light guide plate 1 ′ corresponding to the arrangement position of the imaging units 10 and 20. The optical member 90 may be arranged in the middle of the light path where light finally enters each imaging unit.

  The imaging units 10 and 20 are disposed immediately below the conical surface notch 90a of the optical member 90, and are disposed at two positions apart from each other at the end of the transparent light guide plate 1 ′. Further, the imaging units 10 and 20 do not protrude above the touch surface of the transparent light guide plate 1 ′. The imaging units 10 and 20 have a structure in which light that does not propagate through the transparent light guide plate 1 ′ is not coupled to the imaging elements 13 and 23.

[Embodiment 4]
Another embodiment of the present invention will be described. In addition, in this embodiment, in order to demonstrate a difference from the said Embodiment 1, for convenience of explanation, the same member number is attached | subjected to the member which has the same function as the member demonstrated in Embodiment 1, and the description Is omitted.

  The following will describe another embodiment of the present invention with reference to FIGS.

  The pen input device 40 provided in the input system according to the first embodiment is provided with two imaging units 10 and 20 as detection units, whereas the pen input device 43 according to the present embodiment has FIG. As shown in FIG. 3, the difference is that three image pickup units 10, 20, and 70 (detection units) are provided. Note that three cutouts 1 a are provided in the widened portion of the transparent light guide plate 1 corresponding to the three imaging units 10, 20, and 70.

  By providing this configuration, as shown in FIG. 10, even when there are two pens 3A and 3B (operation members) as detection objects, the position coordinates of each pen can be detected. .

  For example, suppose that only two imaging units are provided, the traveling direction of the propagation light of one pen of the two pens 3A and 3B (the optical path of the propagation light toward the imaging unit) and the propagation light of the other pen When the traveling directions overlap, the linear images also overlap, so it is not possible to specify which of the two pens 3A and 3B is in front. However, in this embodiment, as shown in FIG. 10, if there are three imaging units 10, 20, and 70 as light receiving means, the imaging unit 10 with two optical paths that do not overlap each pen 3 </ b> A and 3 </ b> B. It becomes possible to obtain the contact positions of the pens 3A and 3B using 20 and 70. The imaging unit 70 is the same as the imaging units 10 and 20 and includes a unit lens 71, a visible light cut filter 72, and an imaging element 73.

  Specifically, for example, in FIG. 10, when the pen 3B exists at the point P3, the optical path of the pen 3A to the imaging unit 10 and the optical path of the pen 3B overlap. In this case, two imaging units 20 and 70 are used to detect the pen 3A, while the imaging units 10 and 70 are used to detect the pen 3B. As a result, the optical paths do not overlap.

  Therefore, even if the two pens 3A and 3B are brought into contact with any place on the transparent light guide plate 1, the position coordinates of the contact points of the pens 3A and 3B can be reliably specified.

In general, when there are M pens 3 as objects to be detected, the required number N of detection units is:
N = M + 1
It becomes.

  Further, when at least three imaging units 10, 20, and 70 as detection units are provided, there are the following merits.

  That is, when there are two image pickup units, there is a possibility that when the pen is brought into contact with the vicinity of the side of the transparent light guide plate 1 provided with the two image pickup units, a blind spot is formed and the two image pickup units are not detected. In this case, if there are three imaging units, for example, if they are arranged at the vertices of a triangle, the pen can be touched anywhere on the transparent light guide plate 1 without generating a blind spot. The position coordinates of the contact point of the pen can be reliably specified.

  Thus, in the present embodiment, three imaging units are provided. Thus, for each of the two pens, the contact position of each pen can be obtained using the combination of the imaging unit 20 and the imaging unit 70 by the two optical paths that do not overlap and the combination of the imaging unit 10 and the imaging unit 70. It becomes possible. In addition, by arranging three imaging units at the apexes of the triangle, the position coordinates of the contact point of the pen can be ensured regardless of where the pen touches the transparent light guide plate 1 without generating a blind spot. It becomes possible to specify.

(Modification)
In the present embodiment, the configuration including three imaging units has been described, but the present invention may include four or more imaging units.

  When four imaging units are provided, for example, as shown in FIG. 11, it may be arranged at the four corners of the transparent light guide plate 1. That is, the transparent light guide plate 1 includes a widened portion 5a and a widened portion 5b along each of the long sides, and the four notches 1a are the four corners of the transparent light guide plate 1, and the widened portion 5a. -It is provided in 5b.

  Even when four imaging units are provided, the input from the two pens can be accurately detected as in the present embodiment.

  In this modification, for example, when detecting one pen, any two of the four imaging units 10, 20, 70, and 80 can be used. This is because, for example, when only two imaging units are arranged along one side of the transparent light guide plate 1, the signal quality may be degraded when the pen contact point is far from these imaging units. is there. Therefore, by disposing the imaging units at the four corners of the transparent light guide plate 1 as in this modification, when the contact point of the pen 3 is far from the imaging units 10 and 20, the imaging units 70 and 80, the coordinates of the pen 3 can be detected.

  As mentioned above, although embodiment which concerns on this invention was described, this invention is not limited to said embodiment. Various modifications can be made within the scope of the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[Summary]
The input system according to the first aspect of the present invention includes a display unit (liquid crystal display panel 2) having a display surface, and a rectangular light guide member (transparent) provided to face the display surface and having a long side and a short side. A light extraction portion (notch 1a, optical member 90) for extracting light emitted from the light guide plate 1) and the detected object (pen 3) and propagating through the light guide member to the outside of the light guide member. ) And a detection unit that detects the position of the detected object on the surface of the light guide member based on the light extracted by the light extraction unit, the input system in plan view The optical member includes a widened portion (5, 5a, 5b) that is a portion wider than the display surface along at least one long side, and the light extraction portion is provided in the widened portion. Features.

  According to the above configuration, since the light extraction portion is provided in the widened portion that is wider than the display surface, a sufficient distance can be provided between the display portion and the light extraction portion. The detection accuracy of the detection target in the vicinity of the light extraction portion on the surface (and display surface) of the optical member can be increased.

  Moreover, since the light extraction part is arrange | positioned at the wide part provided along the long side of the light guide member, compared with the case where it is arrange | positioned at the wide part provided along the short side of the light guide member Thus, the distance between the light extraction portion and the corner of the display surface can be shortened. Thereby, the detection accuracy of the to-be-detected body in the corner (and corresponding corner of the display surface) of the light guide member away from the light extraction portion can be increased.

  As described above, the detection accuracy of the detection object in the vicinity of the light extraction unit on the display surface of the display unit can be increased, and the detection accuracy of the detection object in the corner of the display surface far from the light extraction unit can be increased. .

  The input system which concerns on aspect 2 of this invention is provided with the at least 2 said light extraction part in the said aspect 1, and the detection part corresponding to each of the said light extraction part, The said light guide in planar view The member may include the widened portion along one long side, and the light extraction portion may be provided at both ends of the widened portion.

  According to said structure, the position coordinate of the to-be-detected body with respect to a display surface can be detected correctly by providing a light extraction part in the both ends of a wide part.

  Moreover, the enlargement of the light guide member by providing a wide part can be suppressed by providing one wide part and providing a several light extraction part in the said wide part.

  An input system according to aspect 3 of the present invention includes the input system according to aspect 2 including at least three of the light extraction units, and a detection unit corresponding to each of the light extraction units. The structure provided in the wide part at predetermined intervals may be sufficient.

  According to said structure, even if it is a case where two or more to-be-detected bodies exist, the position of each to-be-detected body in the surface of a light guide member can be detected.

  The input system which concerns on aspect 4 of this invention is equipped with the at least 2 said light extraction part and the detection part corresponding to each of the said light extraction part in the said aspect 1, The said light guide in planar view The member includes the widened portion along each of both long sides, and the light extraction portion is provided in each of the widened portions so as to face each other along the short side of the light guide member. It may be a configuration.

  The input system according to aspect 5 of the present invention includes the input system according to aspect 4 including at least four of the light extraction units, and a detection unit corresponding to each of the light extraction units. The structure provided in the four corners of the light guide member may be sufficient.

  According to the above configuration, among the light extraction units and detection units provided at the four corners of the light guide member, the accurate position coordinates of the detection target can be obtained using the two light extraction units and detection units that are closer to the detection target. Can be detected.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention. Furthermore, a new technical feature can be formed by combining the technical means disclosed in each embodiment.

  The present invention can be used for all types of input systems that use a light-emitting pen to determine the position coordinates of a pen.

1, 1 ', 101 Transparent light guide plate (light guide member)
1a, 1a ′ cutout (light path conversion unit, light extraction unit)
2 Liquid crystal display panel (display unit)
3, 3A, 3B pen (light emitting part)
4a, 4b Light flux 5, 5a, 5b, 105 Widening part 6 Mirror coating (optical path conversion part)
10, 20, 10 ′, 20 ′, 70, 80 Imaging unit (detection unit)
DESCRIPTION OF SYMBOLS 11, 21, 71 Lens 12, 22, 72 Visible light cut filter 13, 23, 73 Image pick-up element 15, 17 Line-shaped image 16 Fan-shaped 18 Fan-shaped center 19 Thick line-shaped image 20 Dotted line-shaped image 30 Light emission part 31 Light emitting element 32 Light guide member 33 Power supply device 34 Control device 35 Housing 36 Light diffusion member 40, 41, 42, 43 Pen input device (input device)
50 Input system 90 Optical member (optical path conversion unit, light extraction unit)
90a Notch (light path conversion part, light extraction part)

Claims (5)

A display unit having a display surface;
A rectangular light guide member provided facing the display surface and having a long side and a short side;
A light extraction unit for extracting light emitted from the detected body and propagating through the light guide member to the outside of the light guide member;
A detection unit that detects the position of the detected object on the surface of the light guide member based on the light extracted by the light extraction unit, and an input system comprising:
In plan view, the light guide member includes a widened portion that is a portion wider than the display surface along at least one long side, and the light extraction portion is provided in the widened portion. And input system. At least two of the light extraction units, and a detection unit corresponding to each of the light extraction units,
In plan view, the light guide member includes the widened portion along one long side,
The input system according to claim 1, wherein the light extraction portion is provided at both ends of the widening portion. Comprising at least three light extraction units, and detection units corresponding to the light extraction units,
The input system according to claim 2, wherein the light extraction unit is provided in the widening unit at a predetermined interval. At least two of the light extraction units, and a detection unit corresponding to each of the light extraction units,
In plan view, the light guide member includes the widened portion along each of both long sides,
The input system according to claim 1, wherein the light extraction unit is provided in each of the widened portions so as to face each other along a short side of the light guide member. At least four of the light extraction units, and a detection unit corresponding to each of the light extraction units,
The input system according to claim 4, wherein the light extraction unit is provided at four corners of the light guide member.

Images