JP6078294B2 - Touch panel device - Google Patents

Description

  The present invention includes a display screen for displaying an image, a row of light emitting elements that scans infrared light along the display screen, a row of light receiving elements corresponding to the row of light emitting elements, and the row of light emitting elements or The present invention relates to a touch panel device that includes a translucent plate that covers a row of light receiving elements and detects a position of a light shielding object on the display screen.

  In recent years, coordinates relating to information written on a display screen are detected, and the image displayed on the display screen is overwritten to display the information on the computer or the written information to a computer. Electronic whiteboards that can be captured in real time have become widespread.

  Various methods have been proposed as a coordinate input and coordinate detection method used in an electronic whiteboard, and one of them is an infrared blocking method using infrared rays. FIG. 13 is an explanatory diagram for explaining coordinate detection and coordinate input in an infrared shielding electronic whiteboard.

  In such an infrared blocking electronic whiteboard 200, a number of LEDs 1, 2, 3,... That emit infrared light on one side (not shown) in the vertical direction and one side in the horizontal direction of the display unit 201 are provided. The light receiving elements 1, 2, 3,... (Phototransistors) are arranged in one row at the same interval as the LED rows on the sides facing the LED rows. The light receiving element pairs are sequentially scanned to detect the presence or absence of an infrared light blocking object in the X direction (horizontal) and the Y direction (vertical), and the position of the blocking object is recognized as an input position.

  For example, when the infrared light emitted from the LED 3 is shielded by the shield S, the amount of light received by the light receiving elements 1, 2, 3,. Based on the change in the amount of light received by the light receiving elements 1, 2, 3,. In this example, for a light emission of one LED, a change in the amount of received light is detected by a plurality of light receiving elements.

  On the other hand, in Patent Document 1, when it is detected that there is a light shielding object, the amount of light emitted to the light receiving element that detects the light shielding is increased, or the sensitivity of the light receiving element is increased and scanning is repeated to continue the determination that there is a light shielding object. If it is determined that there is no false detection, and if it is determined that there is no light-shielding object, an infrared ray that can solve the problem of erroneous detection due to the attachment of water droplets is determined by determining that water droplets are attached. An interrupting touch panel device is disclosed.

JP 2005-339342 A

  In the above-described infrared shielding electronic whiteboard, a transmission filter that transmits infrared light from the LED is provided at the boundary between the display screen and the bezel portion where the LED and the light receiving element are arranged. Accordingly, unnecessary incident light from the outside can be blocked in the LED or the light receiving element, and the mounting substrate can be protected.

  However, when infrared light from any LED enters the transmission filter at a shallow angle, the incident light is reflected by the transmission filter, and erroneous detection may occur due to reflection / diffracted light of the light. Hereinafter, such reflected / diffracted light that causes erroneous detection is referred to as stray light.

  For example, as shown in FIG. 13, infrared light emitted from the LED 1 and the LED 2 spreads with a predetermined width, and a part of the light forms a shallow incident angle (inner angle) and is transmitted vertically. When incident on the filter 202, such reflected light is reflected by the transmission filter 202 and travels toward the light receiving element 1 and the light receiving element 2. Therefore, in the light receiving element 1 and the light receiving element 2, the reflected light is received and the amount of received light is changed, so that the detection of the light shielding object S is affected.

  However, the electronic whiteboard according to Patent Document 1 cannot solve such a problem.

The present invention has been made in view of such circumstances, and an object thereof is to provide a display screen for displaying an image, a row of light emitting elements that scans infrared light along the display screen, In a touch panel device, comprising: a row of light receiving elements corresponding to a row of light emitting elements; and a strip-shaped translucent plate covering the row of light emitting elements or the row of light receiving elements, and detecting a position of a light shielding object on the display screen The translucent plate has an inclination angle of 45 ° to 70 ° with respect to the display screen, and a translucent portion is provided in a range that matches the position of the light emitting portion of the light emitting element in the width direction thereof. light absorbing film layer to absorb incident infrared light into the retroreflective layer for reflecting light to the emission source are laminated, the film-shaped light reflection absorption unit, by Rukoto provided one edge of the display screen side The range of the translucent part is minimized, and the width of the translucent plate is reduced. As is to provide a touch panel device capable of suppressing reflection by infrared light transparent plate incident with a shallow angle of incidence.

The touch panel device according to the present invention includes a display screen for displaying an image, a row of light emitting elements that scans infrared light along the display screen, a row of light receiving elements corresponding to the row of light emitting elements, and the light emission. A strip-shaped translucent plate that covers a row of elements or a row of light-receiving elements, and detects the position of a light-shielding object on the display screen. The translucent plate is 45 ° to the display screen. A retroreflective film layer having a tilt angle of ˜70 ° and having a translucent part in a range that matches the position of the light emitting part of the light emitting element in the width direction and reflects incident infrared light to the light emitting source. A film-like light reflection / absorption part on which a light absorption film layer for absorbing incident infrared light is laminated is provided at one edge of the display screen side .

In the present invention, the light emitting element emits within a range in the width direction of the light transmitting plate corresponding to a position aligned with the position of the light emitting portion of the light emitting element in the direction along the width direction of the light transmitting plate. The translucent part where infrared light enters and exits is limited, and the width of the translucent plate is narrowed. In addition, the light reflection / absorption part is provided at one edge of the light transmission plate on the display screen side, and the light reflection / absorption part is incident on the infrared light with a shallow incident angle. Is reflected and absorbed by the light source.

  The touch panel device according to the present invention is characterized in that the light-transmitting plate is provided with the light reflection / absorption part at the other edge part facing the one edge part.

  In the present invention, the light reflection / absorption part is provided at the other edge part of the light transmission plate, and the light reflection / absorption part is incident on the infrared light with a shallow incident angle. Light is reflected and absorbed by its source.

  According to the present invention, by providing the light transmitting part in the minimum range necessary for light emission of infrared light by the light emitting element, the width of the entire light transmitting plate is reduced as much as possible, It is possible to suppress the occurrence of erroneous detection due to the infrared light incident with a shallow incident angle being reflected by the light transmitting plate.

It is the conceptual diagram which displayed notionally the electronic whiteboard of Embodiment 1 of this invention. It is a functional block diagram which shows the principal part structure of the electronic whiteboard of Embodiment 1 of this invention. It is a functional block diagram which shows the principal part structure of the control part in the touch panel part of the electronic whiteboard of Embodiment 1 of this invention. It is a functional block diagram explaining the scanning process of the light in the electronic whiteboard of Embodiment 1 of this invention. It is explanatory drawing explaining the detection and the detection of a light-shielding object in the electronic whiteboard of Embodiment 1 of this invention. It is a partial front view which shows the corner | angular part of the display part in the electronic whiteboard which concerns on Embodiment 1 of this invention. It is sectional drawing by the AB line | wire of FIG. It is explanatory drawing explaining the relationship between the translucent board and light emitting element in the electronic whiteboard which concerns on Embodiment 1 of this invention. It is explanatory drawing explaining the structure of a translucent plate at the time of seeing a translucent plate from the arrow direction in FIG. It is explanatory drawing explaining the structure of the translucent board in the electronic whiteboard which concerns on Embodiment 2 of this invention. In the electronic whiteboard according to Embodiment 3 of the present invention, it is a partial cross-sectional view showing the configuration of a light emitting element and a substrate. In the electronic whiteboard which concerns on Embodiment 4 of this invention, it is a partial cross-sectional view which shows the structure of a translucent board and a frame. It is explanatory drawing explaining the coordinate detection and coordinate input in an infrared rays shielding type electronic whiteboard.

  Hereinafter, the case where the touch panel device according to the present invention is applied to a so-called electronic whiteboard will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a conceptual diagram conceptually showing the electronic whiteboard 100 according to the first embodiment of the present invention, and FIG. 2 is a functional block diagram showing the main configuration of the electronic whiteboard 100 according to the first embodiment of the present invention. It is.

  The electronic whiteboard 100 according to the first embodiment of the present invention includes a display unit 100A and a touch panel unit 100B, and the touch panel unit 100B includes a light emitting element that emits infrared light and a light receiving element that receives infrared light. This is a so-called infrared shielding touch panel that detects the position of an object. In the electronic whiteboard 100, for example, the display unit 100A is connected to a personal computer (hereinafter referred to as a PC) via HDMI, and the touch panel unit 100B is connected via USB. In this embodiment, the display unit 100A and the touch panel unit 100B are configured independently for each function of video display and coordinate instruction, but are integrated for the purpose of synchronizing the display and coordinate instruction. It may be configured and controlled automatically. Further, the I / F for video display and coordinate instruction is not limited to HDMI and USB, and other methods may be used.

  The display unit 100A includes, for example, an LCD or an EL (Electroluminescence) panel, and displays video output from the PC and characters, line drawings, and the like received from the user via the touch panel unit 100B and the PC. In addition, a touch panel unit 100B is provided so as to surround the display screen of the display unit 100A.

  The touch panel unit 100 </ b> B includes a control unit 1, a ROM 2, a RAM 3, an I / F unit 5, and a scanning unit 9, and transmits / receives coordinate data to / from the PC via the I / F unit 5.

  The control unit 1 of the touch panel unit 100 </ b> B displays characters, line drawings, and the like on the display unit 100 </ b> A by accepting writing / drawing of characters, line drawings, and the like via the PC based on the coordinates related to the scanning result by the scanning unit 9.

  A control program is stored in the ROM 2 in advance, and the RAM 3 temporarily stores data and can be read out regardless of the storage order, storage position, or the like. The RAM 3 stores, for example, a program read from the ROM 2 and various data generated by executing the program.

  The control unit 1 loads the control program stored in advance in the ROM 2 onto the RAM 3 and executes it, thereby controlling the various hardware described above via the bus and causing the touch panel unit 100B to function.

  FIG. 3 is a functional block diagram showing a main configuration of the control unit 1 in the touch panel unit 100B of the electronic whiteboard 100 according to Embodiment 1 of the present invention. The control unit 1 includes a CPU 11, a coordinate calculation unit 12, a light shield management unit 13, and a detection unit 14.

  The coordinate calculation unit 12 calculates the coordinates on the display screen of the display unit 100A of a light shielding object such as a pen-shaped input device or a finger. Specifically, the coordinates of such a light blocking object are calculated based on an intensity signal described later, which is transmitted when the light blocking on the display screen of the display unit 100A is detected by the touch panel unit 100B.

  The light shielding object management unit 13 manages the position (coordinates) of the light shielding object detected by the scanning of the scanning unit 9. For example, when the light shielding object moves, the light shielding object management unit 13 stores a coordinate history representing the movement of the light shielding object.

  The detection unit 14 detects the position of one or more light shielding objects on the display screen of the display unit 100A. Specifically, the scanning unit 9 of the touch panel unit 100B scans the entire area on the display screen of the display unit 100A, and the detection is performed based on the intensity signal related to the result of the wide area scanning acquired from the touch panel unit 100B. The unit 14 detects the coordinates of the light shielding object on the display screen of the display unit 100A.

  Further, the CPU 11 controls the light emitting element and the light receiving element of the scanning unit 9.

  The touch panel unit 100B is an infrared shielding touch panel as described above. That is, when the light blocking is detected when the tip of a pen-shaped input device or a finger (not shown) comes close to the display screen of the display unit 100A, such a light shielding object (such as a pen-shaped input device or a finger) is detected. Detect position. That is, as a result of scanning, a signal (intensity signal) obtained from the light receiving element is sent to the control unit 1, and based on this, the coordinate calculation unit 12 calculates the coordinates of such a light shielding object. In this way, the touch panel unit 100B accepts input of position designation on the display unit 100A, characters, line drawings, and the like from the user.

  The touch panel unit 100B includes a scanning unit 9 that scans infrared light (hereinafter referred to as infrared light) along the display screen of the display unit 100A. The scanning unit 9 irradiates infrared light. A light emitting unit 91 having a plurality of light emitting elements, a light receiving unit 92 having a plurality of light receiving elements for receiving infrared light from the corresponding light emitting elements, and a light emitting signal and a light receiving signal from the control unit 1 (CPU 11). And an address decoder 93 assigned to the light receiving unit 92 and an A / D converter 94 for converting an analog signal from the light receiving unit 92 used to detect light blockage into a digital signal.

  FIG. 4 is a functional block diagram illustrating light scanning processing in the electronic whiteboard 100 according to Embodiment 1 of the present invention.

  The light emitting unit 91 has a multiplexer (not shown), and each of the light emitting elements is connected to the multiplexer. The light receiving unit 92 also includes a multiplexer (not shown), and each of the light receiving elements is connected to the multiplexer. Further, each light emitting element of the light emitting unit 91 is configured to correspond (oppose) to any one light receiving element of the light receiving unit 92.

  The CPU 11 of the control unit 1 outputs a light emission signal for causing the plurality of light emitting elements to emit light to the address decoder 93A, and outputs a light reception signal for causing the plurality of light receiving elements to receive light to the address decoder 93B. The address decoder 93A outputs, to the light emitting unit 91, a signal for specifying any one of the light emitting elements related to light emission in response to the signal from the CPU 11, and the address decoder 93B responds to the signal from the CPU 11. Then, a signal for specifying the light receiving element corresponding to the specified light emitting element among the light receiving elements is output to the light receiving unit 92.

  The light emitting element thus identified emits infrared light, and the corresponding light receiving element receives infrared light. At this time, an intensity signal indicating the intensity of the infrared light received by the light receiving element as a voltage value is output to the A / D converter 94. The A / D converter 94 converts the intensity signal into an 8-bit digital signal, for example, and outputs the converted intensity signal to the control unit 1. The control unit 1 sequentially repeats the process of acquiring the intensity signal from each light receiving element in order to acquire the intensity signal from all the light receiving elements.

  The CPU 11 of the control unit 1 calculates the amount of light received by the light receiving element based on the intensity signal acquired from each light receiving element. When the calculated amount of received light exceeds a predetermined threshold, the CPU 11 determines that the optical path of the infrared light received by the light receiving element is not blocked. When the calculated amount of received light is equal to or less than a predetermined threshold, it is determined that the optical path of infrared light received by the light receiving element is blocked.

  Based on the determination result of the CPU 11, the coordinate calculation unit 12 and the detection unit 14 calculate the position of the light shielding object. That is, the coordinate calculation unit 12 and the detection unit 14 specify a light receiving element whose infrared light path is blocked, and based on the position of the specified light receiving element, the coordinates of the light shielding object on the display screen of the display unit 100A. The process which calculates is performed.

  Hereinafter, the scanning and detection of the light shielding object will be described in detail. FIG. 5 is an explanatory diagram for explaining scanning and detection of a light shielding object in the electronic whiteboard 100 according to Embodiment 1 of the present invention.

  The display screen of the display unit 100A has a rectangular shape, and a plurality of light emitting elements 911, 911,... Are arranged in parallel along the edge of the display unit 100A on the right side and the lower side of the display screen in the drawing. . The light emitting element 911 is, for example, a light emitting diode (LED) that emits infrared light. In the drawing, the optical path of the infrared light emitted from each light emitting element 911 is indicated by a solid arrow.

  The plurality of light emitting elements 911, 911,... On the right side are provided so that the optical paths of the infrared light emitted from the respective light emitting elements 911 are parallel to each other along the display screen. , 911,... Are similarly provided.

  That is, the right light-emitting elements 911, 911,... In the left-right direction (x-axis direction) and the plurality of lower light-emitting elements 911, 911,. They are provided so as to be orthogonal to each other.

  Further, on the display screen of the display unit 100A, light receiving elements 921, 921,... Are provided at positions facing the light emitting elements 911, 911,.

  That is, on the left and upper sides of the display screen of the display unit 100A, a plurality of light receiving elements 921, 921,. The light receiving element 921 is a light receiving diode that receives infrared light. The infrared light from the light emitting elements 911, 911,... Is received by the light receiving elements 921, 921,.

  As in the case of the light emitting elements, the upper light receiving elements 921, 921, ... and the left light receiving elements 921, 921, ... are provided so that the optical paths of the infrared light to be received are orthogonal to each other.

  The scanning unit 9 sequentially causes the light emitting elements 911 to emit light one by one from one end to the other end in the X-axis direction and from one end to the other end in the Y-axis direction on the display screen of the display unit 100A. The position, size, etc. of the light-shielding object on the display screen are detected as described above.

  6 is a partial front view showing a corner portion of display portion 100A in electronic whiteboard 100 according to Embodiment 1 of the present invention, and FIG. 7 is a cross-sectional view taken along line AB in FIG.

  The electronic whiteboard 100 includes a display screen 101 of the display unit 100 </ b> A and a bezel unit 8 provided around the edge of the display screen 101.

  The bezel portion 8 has a hollow frame 82 that holds the edge of the display screen 101, and light emitting elements 911, 911,. A light transmitting plate 81 is provided at the end of the bezel portion 8 on the display screen 101 side.

  As described above, the translucent plate 81 is a strip-shaped plate material provided so as to cover the light emitting elements 911, 911,... And the light receiving elements 921, 921,. It is. The translucent plate 81 transmits infrared light emitted from the light emitting elements 911, 911,..., And prevents the light emitting elements 911, 911 and the light receiving elements 921, 921,. It plays the role of blindfolding and protecting the substrate on which the light emitting element / light receiving element is mounted.

  The translucent plate 81 has a width L of, for example, 16 mm, and is adhered to the end portion with an adhesive or the like in a state where both long side portions on the back side are supported by the end portions of the frame body 82. . The translucent plate 81 is provided so that one long side thereof is substantially in contact with the display screen 101 and forms a specific inclination angle θ with the display screen 101.

  The specific inclination angle θ is designed to be, for example, 70 ° to 45 °. As a result, as shown in FIG. 13, infrared light incident at a shallow incident angle on the light transmitting plate 81 covering the row of the light emitting elements 911 (or the light receiving elements 921) is reflected in the front direction of the display screen 101. -It can be avoided and erroneous detection due to direct reflection can be suppressed.

  As described above, it is possible to suppress misdetection of coordinates due to stray light by the inclination angle θ of the translucent plate 81. In general, infrared light is diffused light whose beam diameter expands depending on the distance. Therefore, a certain amount of stray light remains depending on the lens and focal length of the light emitting element and the dimensions of the frame body 82. For this reason, the electronic whiteboard 100 according to the present invention has the following mechanism in order to prevent unnecessary reflection of the translucent plate itself.

  Inside the frame 82, light emitting elements 911, 911,... Are mounted on a substrate 912 arranged orthogonal to the display screen 101, and infrared light emitted from the light emitting portions of the light emitting elements 911, 911,. It passes through the optical plate 81 and proceeds toward the light receiving elements 921, 921,.

  FIG. 8 is an explanatory diagram for explaining the relationship between the translucent plate 81 and the light emitting element 911 in the electronic whiteboard 100 according to Embodiment 1 of the present invention.

  The translucent plate 81 includes a translucent portion 812 that transmits infrared light from the light emitting elements 911, 911,..., And other light emitting elements that are incident at a shallow incident angle from the end side of the translucent plate 81. An upper antireflection part 811 and a lower antireflection part 813 for preventing reflection of infrared light are provided. Here, the width of the long side of the upper antireflection portion 811 is L1, the width of the light transmitting portion 812 is L2, and the width of the lower antireflection portion 813 is L3. That is, the width L of the long side of the translucent plate is L = L1 + L2 + L3. Further, as will be described later, the translucent plate 81 includes a retroreflective film part 811A, a retroreflective film part 813A, a light absorption film part 811B, or a light absorption film part 813B.

  FIG. 9 is an explanatory diagram for explaining the configuration of the light transmitting plate 81 when the light transmitting plate 81 is viewed from the direction of the arrow in FIG.

  The light transmitting portion 812 corresponds to a range that matches the light emitting portion 913 of the light emitting element 911 in the width direction of the light transmitting plate 81. More specifically, the width L2 of the light transmitting portion 812 can be expressed by an expression L2 = W / sin θ, where W is the outer dimension of the light emitting portion 913 of the light emitting element 911. Therefore, the translucent part 812 has a range L <b> 2 that matches the outer dimension W of the light emitting part 913 in the width direction of the translucent plate 81.

  Further, an upper antireflection part 811 (other edge part) is provided on one long side of the translucent plate 81, and a lower antireflection part 813 (one edge part) is provided on the other long side. It has been. More specifically, a lower antireflection part 813 is provided on the display screen 101 side with the light transmitting part 812 interposed therebetween, and an upper antireflection part 811 is provided on the opposite side. The widths of the upper antireflection part 811, the translucent part 812, and the lower antireflection part 813 in the width direction of the translucent plate 81 are, for example, 6 mm, 6 mm, and 4 mm, respectively.

  The upper antireflection part 811 has a retroreflection film part 811A or a light absorption film part 811B, and the lower antireflection part 813 has a retroreflection film part 813A or a light absorption film part 813B. That is, both the upper antireflection part 811 and the lower antireflection part 813 may have a retroreflection film part or a light absorption film part, and the upper antireflection part 811 and the lower antireflection part 813 are each retroreflective. The structure which has a film part or a light absorption film part may be sufficient. The retroreflective film portions 811A and 813A reflect incident infrared light in the direction of the light emitting source. Further, the light absorbing film portions 811B and 813B absorb incident infrared light.

  The retroreflective film portions 811A and 813A are made of a retroreflective material such as a micro prism type or a bead type, for example. The microprism type has, for example, a trihedral cube layer that reflects incident infrared light to the light source, and the bead type has a glass bead layer on the front side of the reflective film layer. Since these are known techniques, a detailed description thereof will be omitted.

  The light absorption film portions 811B and 813B include, for example, compounds such as azo, aminium, anthraquinone, cyanine, diimonium, dithiol metal complex, squarylium, naphthalocyanine, and phthalocyanine.

  In addition to this, surface blasting such as polishing, application of matte coating agent, AR (Anti Reflection) film, pasting of moth-eye film, etc., processing that absorbs and diffuses the wavelength of infrared light irradiated from LED, dye・ Applying paint or sticking film is desirable.

  The retroreflective film portions 811A and 813A and the light absorption film portions 811B and 813B are formed on the front side of the upper antireflection portion 811 and / or the lower antireflection portion 813.

  With the above configuration, infrared light from other light-emitting elements that are incident at a shallow incident angle from the end side of the light-transmitting plate 81 is reflected and / or absorbed by the light source, resulting in the stray light. It is possible to prevent erroneous detection of the light shielding object.

(Embodiment 2)
The electronic whiteboard 100 according to the second embodiment of the present invention has substantially the same configuration as the electronic whiteboard 100 according to the first embodiment, but differs in the configuration of the translucent plate 81.

  FIG. 10 is an explanatory diagram for explaining the configuration of the translucent plate 81 in the electronic whiteboard 100 according to Embodiment 2 of the present invention.

  In the electronic whiteboard 100 according to the second embodiment, the upper antireflection part 811 and / or the lower antireflection part 813 is configured to have both retroreflective film parts 811A and 813A and light absorption film parts 811B and 813B. ing.

  For example, as shown in FIG. 10A, the upper antireflection portion 811 and the lower antireflection portion 813 are provided with light reflection absorption film portions 811C and 813C, respectively. Further, the light reflection / absorption film portions 811C and 813C have a configuration in which the light absorption film portions 811B and 813B are formed on the surfaces of the retroreflection film portions 811A and 813A (see FIG. 10B).

  With such a configuration, the light reflection / absorption film portions 811C and 813C reflect the infrared light incident on the light transmission plate 81 at a shallow incident angle from the end side of the light transmission plate 81 and absorb the light. Therefore, it is possible to prevent erroneous detection of the light shielding object due to the reflected infrared light.

  In the present embodiment, the case where both the upper antireflection part 811 and the lower antireflection part 813 have the light reflection / absorption film part has been described as an example. However, the present invention is not limited to this. May have a light reflection / absorption film part, and the other may have a retroreflection film part or an absorption film part.

(Embodiment 3)
The electronic whiteboard 100 according to the third embodiment of the present invention has substantially the same configuration as the electronic whiteboard 100 according to the first embodiment, but is different in the configuration of the light emitting elements 911, 911,. To do.

  FIG. 11 is a partial cross-sectional view showing configurations of light emitting elements 911, 911,... And substrate 912 in electronic whiteboard 100 according to Embodiment 3 of the present invention.

  The substrate 912 has a strip shape, and is provided inside the frame body 82 so that the surface direction thereof is parallel to the surface direction of the display screen 101.

  The light emitting element 911 is provided such that the light emitting portion 913 is aligned with the light transmitting portion 812 in the width direction of the light transmitting plate 81, and is connected to the substrate 912 by lead wires 914 and 914. The light emitting element 911 is mounted so that an optical path of infrared light emitted from the light emitting unit 913 and traveling through the light transmitting unit 812 is along the surface of the display screen 101.

  The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

(Embodiment 4)
The electronic whiteboard 100 according to the fourth embodiment of the present invention has substantially the same configuration as the electronic whiteboard 100 according to the first embodiment, but is different in the configuration of the translucent plate 81 and the frame body 82.

  FIG. 12 is a partial cross-sectional view showing the configuration of the translucent plate 81 and the frame body 82 in the electronic whiteboard 100 according to Embodiment 4 of the present invention.

  In the electronic whiteboard 100 according to the fourth embodiment, the frame 82 is formed with grooves 83 and 83 for holding the translucent plate 81 at the end thereof. That is, the upper reflection preventing portion 811 side long side portion and the lower reflection preventing portion 813 side long side portion of the translucent plate 81 are respectively locked by the grooves 83 and 83 of the frame body 82.

  The insides of the grooves 83 and 83 have a shape that follows both long side portions of the translucent plate 81, and the translucent plate 81 is slidably locked. For example, when the translucent plate 81 is assembled, the translucent plate 81 may be inserted into the grooves 83 and 83 from one opening end of the grooves 83 and 83 and slid.

  In the state where the light transmitting plate 81 is locked in the state of the grooves 83 and 83, the exposed portion viewed from the front side of the display screen 101 is similar to the upper antireflection portion 811 or the lower antireflection portion 813. A retroreflective film part or a light absorption film part is provided.

  That is, the exposed portion 83A on the upper antireflection portion 811 side and the exposed portion 83B on the lower antireflection portion 813 side are exposed portions of the grooves 83, 83, and the retroreflective film portion and / or A light absorption film portion is formed.

  With such a configuration, infrared light that is incident on the light transmitting plate 81 at a shallow incident angle from the end side of the light transmitting plate 81 is prevented from being reflected by the bezel portion 8 and is blocked by the reflected light resulting therefrom. It is possible to prevent an object from being erroneously detected.

  The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the above description, the translucent plate 81 covering the light emitting elements 911, 911,... Has been described as an example, but the present invention is not limited to this, and the translucent plate 81 covering the light receiving elements 921, 921,. Needless to say, the same is true.

81 translucent plate 91 light emitting unit 92 light receiving unit 100 electronic whiteboard 100A display unit 100B touch panel unit 101 display screen 811 upper antireflection unit 812 translucent unit 813 lower antireflection unit 811A, 813A retroreflective film unit 811B, 813B light absorbing film Portion 811C, 813C Light reflection / absorption film portion 911 Light emitting element 921 Light receiving element

Claims (2)

A display screen for displaying an image; a row of light emitting elements that scans infrared light along the display screen; a row of light receiving elements corresponding to the row of light emitting elements; and the row of light emitting elements or the row of light receiving elements In a touch panel device for detecting the position of a light-shielding object on the display screen,
The translucent plate is
An inclination angle of 45 ° to 70 ° with respect to the display screen;
It has a translucent part in a range that matches the position of the light emitting part of the light emitting element in the width direction ,
A film-like light reflection / absorption part in which a light absorption film layer that absorbs incident infrared light is laminated on a retroreflective film layer that reflects incident infrared light to a light emitting source is provided at one edge of the display screen side. the touch panel and wherein the are. The transparent plate includes a touch panel device according to claim 1, the other edge opposite to the one edge, characterized in that it provided the light reflection absorption unit.

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