JP2014021790A - Coordinate input device, coordinate detection method and coordinate input system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical coordinate input device, a coordinate detection method and a coordinate input system using a light guide member capable of efficiently detecting the coordinate positions of a non-light emitting object to be detected such as the finger and a light emitting object to be detected such as a light emitting pen.SOLUTION: A coordinate input device 3A includes: a light guide plate 10; a light guide unit 4A connected to the edge of the light guide plate 10 for illuminating the inside of the light guide plate 10; and two imaging units 20 and 30 for detecting the traveling direction of propagating lights propagating inside the light guide plate 10 generated when a finger 8 and a light emitting pen 9 are brought into contact with the light guide plate 10, in which the position coordinates of a contact point are obtained by a triangulation method on the basis of the detection of the traveling direction of the propagating lights by the imaging units 20 and 30. The coordinate input device 3A includes: an illumination light source lighting control section 15 for periodically blinking the light source unit 4A; and a detection section 6 for detecting the position of the finger 8 in the lighting period of the light source unit 4A, and for detecting the position of the light emitting pen 9 in the lighting-out period of the light source unit 4A.

Description

  The present invention relates to an optical coordinate input device, a coordinate detection method, and a coordinate input system for obtaining a position coordinate of a contact point by a triangulation method using a light guide member. And using a light-emitting pen together.

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

  In the coordinate input system, the coordinate input device or the position detection device obtains the coordinates of the approached or touched position of the pen or finger by causing the pen or finger to approach or contact the coordinate input area of the coordinate input device. The obtained coordinates are for displaying 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 panel integrally laminated on the coordinate input device. Used for etc.

  For example, as shown in FIG. 23, the touch panel 100 disclosed in Patent Document 1 includes a light guide plate 102 on a display 101, and at least two positions (not shown) of the light-emitting pen 103 in contact with the light guide plate 102. It is determined by a detector.

  In addition, as shown in FIG. 24A, the coordinate input device 200 disclosed in Patent Document 2 has light receivers 202... Arranged at four corners of a flat plate member 201 made of a rectangle. Then, the coordinate position (x, y) when the flat plate member 201 is touched with the light-emitting pen 203 is the distance from the touch position to the light receivers 202... It is determined by r1 to r4. The distances r1 to r4 can be obtained as being proportional to the received light intensity at the light receivers 202.

  Further, for example, the touch panel 300 disclosed in the first embodiment of Patent Document 3 includes a light guide plate 301 and a light source 302 that makes light incident on the light guide plate 301 as illustrated in FIGS. And the light receiving elements 304 and 305 arranged on a part of the side surface of the light guide plate 301, and the light from the light source 302 scattered by the detected object 310 between the side surface of the light guide plate 301 and the light receiving elements 304 and 305. An image forming unit 307 for forming an image on the elements 304 and 305 is provided. In addition, light absorbing means 308 is disposed on the side surface of the light guide plate 301 on which the light receiving elements 304 and 305 are disposed, and the light receiving elements 304 and 305 are outside the irradiation range of the light source 302 as shown in FIG. Has been placed.

  The principle of coordinate detection of the touch panel 300 is as follows.

  Light emitted from the light source 302 disposed on the side surface of the light guide plate 301 propagates while repeating total reflection inside the light guide plate 301. In a state where the detection target 310 such as a finger is not touched on the light guide plate 301, the light receiving elements 304 and 305 are disposed outside the irradiation range of the light source 302, and thus do not receive the propagation light propagating inside the light guide plate 301. On the other hand, when the detection object 310 such as a finger is touched on the transparent light guide plate 301, the propagation light in the light guide plate 301 is disturbed at the touch position of the detection object 310, and scattered light is generated. A part of the scattered light also propagates in the direction of the light receiving elements 304 and 305 and is received by the light receiving elements 304 and 305 as shown in FIGS. Thus, the azimuth angle is measured, and the point where the scattered light is generated by the triangulation method, that is, the point where the detected object 310 such as a finger is touched is specified.

  Moreover, in 3rd Embodiment of patent document 3, as shown to Fig.27 (a) (b), the light source 302a, the light receiving element 304a, the light source 302b, and the light receiving element 304b are each on the end surface which the light-guide plate 301 faces. There is described a touch panel 300 ′ that can be arranged and light sources 302a and 302b are alternately turned on to eliminate the influence of light directly reaching the light receiving elements 304a and 304b. As a result, the degree of freedom of arrangement of the light sources 302a and 302b and the light receiving elements 304a and 304b can be increased.

  By the way, in such a touch panel 300 ′, there are cases where it is desired to have a plurality of detected bodies such as fingers. In such a case, when there are only two light receiving elements, there are a plurality of possible combinations of the contact position on the detection object such as a finger, and the contact position cannot be determined. In this case, by using at least three light receiving elements, it is possible to determine the contact position on the detection object such as a plurality of fingers.

  As described above, in the coordinate input device, the detected body is roughly divided into a pen and a finger. For pen input, a light-emitting pen with a built-in light source is used to detect scattered light that is optically coupled at a contact point with the light guide plate by a light receiving means such as an image sensor. In finger input, total reflected light is guided into the light guide plate by an illumination light source for finger input, and a light guide component of scattered light generated at the finger contact point is detected by an image sensor.

  Here, by using both a pen and a finger, it is conceivable that a fine character or picture is input to the pen input, and gesture operations such as reduction, enlargement, rotation, and page feed are performed by the finger input.

JP 2005-520239 Gazette (announced July 7, 2005) Japanese Patent Laid-Open No. 11-327769 (published on November 30, 1999) JP 2009-258967 A (published on November 5, 2009)

  However, the conventional coordinate input devices disclosed in Patent Documents 1 to 3 do not disclose both pen and finger inputs.

  Here, in order to use both finger input and pen input, in order to separate finger input and pen input, the wavelength of the finger illumination light source and the wavelength of the light emitting pen light source are changed, and a specific wavelength is set before the image sensor. It is conceivable to install a wavelength filter that only transmits light.

  For example, a finger imaging unit having a filter that selectively transmits the first wavelength λ1 with the light source wavelength of finger illumination as the first wavelength λ1, the light source wavelength of the light source built in the pen as the second wavelength λ2, A pen imaging unit having a filter that selectively transmits two wavelengths λ2 may be separately provided.

  However, such a configuration in which imaging units having individual types of filters are added has a problem in that the number of imaging units increases, the apparatus size increases, and the cost increases.

  Here, in the coordinate input system, since a touch panel (light guide plate) is placed on the display surface, it is preferable that the finger illumination light source uses infrared light so as not to affect the screen display quality. In this case, the infrared sensitivity of the image sensor decreases on the long wavelength side. In addition, the use of a light source with a special wavelength increases the cost. Therefore, it is better that the number of light source wavelengths used is as small as possible.

  The present invention has been made in view of the above-described conventional problems, and an object thereof is an optical coordinate input device using a light guide member, such as a non-light-emitting object to be detected such as a finger, and a light-emitting pen. It is an object of the present invention to provide a coordinate input device, a coordinate detection method, and a coordinate input system that can efficiently detect both coordinate positions of a light emitting target.

  In order to solve the above problems, a coordinate input device of the present invention includes a light guide member, an illumination light source that is coupled to an edge of the light guide member and illuminates the inside of the light guide member, and a non-light-emitting detection target. Propagation by the direction detecting means, comprising at least two direction detecting means for detecting the traveling direction of the propagating light propagating through the inside of the light guide member that is generated when the light emitting target comes into contact with the light guide member. In a coordinate input device for obtaining a position coordinate of a contact point by triangulation based on detection of a traveling direction of light, an illumination light source blinking means for periodically blinking the illumination light source, and the non-light emission during a lighting period of the illumination light source Detection means for detecting the position of the detected object and detecting the position of the light-emitting detected object during the extinguishing period of the illumination light source is provided.

  In order to solve the above-mentioned problem, the coordinate detection method of the present invention is a coordinate detection method using the coordinate input device described above, wherein the illumination light source is periodically blinked and no light is emitted during the lighting period of the illumination light source. The position of the detected object is detected, and the position of the light emitting detected object is detected during the extinguishing period of the illumination light source.

  According to the above invention, the coordinate input device includes a light guide member, an illumination light source that is coupled to the edge of the light guide member and illuminates the inside of the light guide member, a non-light-emitting detection object, and a light-emitting detection object. And at least two direction detection means for detecting the traveling direction of propagating light propagating through the inside of the light guiding member generated when the light guiding member comes into contact with the light guiding member, and the traveling direction of the propagating light by the direction detecting means Based on this detection, the position coordinates of the contact point are obtained by triangulation.

  By the way, in such a coordinate input device, for example, when both a non-light emitting object to be detected such as a finger and a light emitting object to be detected such as a light emitting pen are used, the non-light emitting object to be separated is used. If the illumination light source and the light emission wavelength of the light emitting detection object are made different and the direction detecting means is provided with a filter for distinguishing the two, the number of parts increases and the cost increases.

  Therefore, in the present invention, the illumination light source blinking means for periodically blinking the illumination light source, the position of the non-light emitting detection object is detected during the lighting light source lighting period, and the light emission detection object is detected during the lighting light source extinguishing period. Detection means for performing position detection is provided. Thereby, the illumination light source blinks periodically by the illumination light source blinking means. Then, the detection means detects the position of the non-light emitting detection object during the lighting period of the illumination light source, and detects the position of the light emission detection object during the extinguishing period of the illumination light source.

  As a result, even if the light emission wavelength of the illumination light source and the light emission wavelength of the light emission detection target are the same, they can be easily distinguished and detected by shifting the detection time. Note that, by setting the blinking period of the illumination light source to, for example, 100 Hz or more, it can be considered that both are detected substantially at the same time.

  Therefore, in an optical coordinate input device that uses a light guide member, a coordinate input device that can efficiently detect the coordinate positions of both a non-light emitting target such as a finger and a light emitting target such as a light emitting pen. Can be provided.

  In the coordinate input device of the present invention, the illumination light source includes a first illumination light source and a second illumination light source, the direction detection unit includes a pair of first direction detection units and a pair of second direction detection units, and the light guide. The first edge of the member is provided with the first illumination light source and a pair of first direction detecting means, and the second edge of the light guide member facing the first edge is the second edge. An illumination light source and a pair of second direction detection means are provided, the first direction detection means is installed outside the irradiation range of the first illumination light source, and the second direction detection means is an irradiation range of the second illumination light source. The first illumination light source and the second illumination light source that are installed outside emit light having different wavelengths, and the light emission detection target is either the first illumination light source or the second illumination light source. Emits light of the same wavelength as the first direction detecting means. The first illumination light source filter that selectively transmits light from the first illumination light source is provided, and the second direction light detector selectively transmits the light from the second illumination light source. The illumination light source blinking means alternately turns on the first illumination light source at the first edge and the second illumination light source at the second edge, and the detection means Non-light-emitting detection target using a pair of first direction detection means or second direction detection means on the side where the first illumination light source or the second illumination light source is lit during the lighting period of the illumination light source or the second illumination light source On the other hand, it is possible to detect the position of the light emitting detection object using the pair of first direction detection means or the pair of second direction detection means.

  Thus, the first and second illuminating light sources having different wavelengths are provided on the first edge and the second edge, which are the two opposite sides of the light guide member, and these are lit alternately. For example, when the first illumination light source having the first wavelength emits light, a first illumination light source filter on the first illumination light source side (transmitting the first wavelength and blocking the second wavelength described later) is provided. The pair of first direction detection means detects the positions of the non-light emitting target and the light emitting target. The signal of the light emission target is always detected, but the signal of the non-light detection target is detected only during the lighting period of the first illumination light source. As a result, it is possible to reliably detect the signal of the non-light emitting target by performing the signal removal processing of the light emitting target.

  On the other hand, when the second illumination light source having the second wavelength emits light, the second illumination light source filter on the second illumination light source side is provided with a second illumination light source filter (blocking the first wavelength and transmitting the second wavelength). The direction detection means detects the position of the non-light emitting target. The signal of the light emission target and the direct light from the first illumination light source are blocked by the second illumination light source filter. In this case, the signal of the light emission target can be detected by using the light emission target of the second wavelength.

  As a result, the common optical system, that is, the first illumination light source, the first illumination light source filter and the pair of first direction detection means, or the second illumination light source, the second illumination light source filter and the pair of second direction detection means is used. Thus, it is possible to separate and detect the signal of the non-light emitting target and the signal of the light emitting target. In this case, the light from the non-light emitting detection object is not directly incident on the pair of second direction detecting means on the opposite side due to the operational effects of the first illumination light source filter and the second illumination light source filter.

  Therefore, the first illumination light source, the first illumination light source filter and the pair of first direction detection means, or the second illumination light source, the second illumination are provided on the first edge and the second edge, which are two opposite sides. Since the light source filter and the pair of second direction detection means are arranged, it is possible to reliably detect multi-touch between the non-light emitting target and the light emitting target.

  In the coordinate input device of the present invention, the light emission target is different from the first light emission target that emits light of the same first wavelength as the light emitted from the illumination light source, and the light of the first wavelength. The at least two direction detection means includes a selection region that selectively transmits the light having the first wavelength, and the first wavelength. And a non-selection region that transmits both light of the second wavelength and light of the second wavelength.

  Thereby, in at least two direction detection means, only one merge filter is provided, respectively, and the coordinates of one finger as the non-emission detected object and the first emission detected object and the second emission detected object are provided. The position can be detected.

  Therefore, since the number of direction detection means is not increased, the coordinate input device can be used in combination with one non-light emitting detection object and two light emission detection objects while suppressing an increase in the number of parts and cost. Can be provided.

  In order to solve the above problems, a coordinate input system according to the present invention is a coordinate input system including the coordinate input device described above, and includes an image display module.

  According to said invention, a coordinate input device can be functioned as a touch panel which inputs with non-light-emission detected bodies, such as a finger, and light-emission detected bodies, such as a light-emitting pen, seeing the image of an image display module. Therefore, even when applied to a large touch panel in an optical coordinate input device using a light guide member, the coordinate positions of both the finger that is a non-light emitting target and the light emitting pen that is a light emitting target are detected. It is possible to provide a coordinate input system including a coordinate input device.

  As described above, the coordinate input device according to the present invention performs illumination light source blinking means for periodically blinking the illumination light source, detects the position of the non-light-emitting detection target during the illumination light source lighting period, and turns off the illumination light source. Detecting means for detecting a position of the light emitting detection object during the period.

  As described above, the coordinate detection method of the present invention is a coordinate detection method using the coordinate input device described above, wherein the illumination light source is periodically blinked, and the non-light emitting target is detected during the lighting period of the illumination light source. This is a method of detecting the position of the light emitting detection object during the extinguishing period of the illumination light source.

  As described above, the coordinate input system of the present invention is a coordinate input system including the coordinate input device described above, and includes an image display module.

  Therefore, in an optical coordinate input device that uses a light guide member, a coordinate input device that can efficiently detect the coordinate positions of both a non-light emitting target such as a finger and a light emitting target such as a light emitting pen. There is an effect that a coordinate detection method and a coordinate input system are provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view illustrating an overall configuration of a coordinate input system including a coordinate input device according to an embodiment of a coordinate input device and a coordinate input system according to the present invention. It is a disassembled perspective view which shows the structure of the said coordinate input system. (A) is a top view which shows the structure of a coordinate input system, (b) is side sectional drawing which shows the structure of a coordinate input system. (A) is a side view which shows the structure of a coordinate input system, (b) is a principal part side view which expands and shows the structure of the edge part of a coordinate input system. FIG. 9 illustrates a configuration of a coordinate input system, and is a cross-sectional view taken along line AA in FIG. 8. It is a top view which shows the irradiation area | region to the light-guide plate in one LED. (A) (b) is sectional drawing which shows the structure of the optical coupling member provided between the light-guide plate and LED. It is a perspective view which shows the optical path of scattered light when a finger touches a light-guide plate. (A) is a top view which shows the detection principle of a coordinate input device, (b) is a wave form diagram which shows the optical signal of the image pick-up element in the imaging unit of a coordinate input device. (A) is a top view which shows the contact position when a finger | toe contacts the various places in the surface of a light-guide plate, (b) is the pixel number which appears in the detection image of an image pick-up element corresponding to the contact position of this finger | toe It is a wave form diagram which shows the relationship with signal strength. (A) is a perspective view which shows the imaging condition in the imaging unit in the said coordinate input device, (b) is a top view which shows the image in the image pick-up element of the said imaging unit. It is a top view which removes a part of housing | casing and shows the structure of the light emission pen as a light emission to-be-detected body in the said coordinate input device. It is sectional drawing which shows the optical path of the propagation light when a light emission pen is touched to the light-guide plate. (A) is a top view which shows the structure at the time of lighting of a light source unit, (b) is a wave form diagram which shows the detection signal of a finger | toe and a light emission pen at the time of lighting of a light source unit, (c) is light extinction of a light source unit. It is a top view which shows the structure at the time, (d) is a wave form diagram which shows the detection signal of the light emission pen at the time of light extinction of a light source unit. The other embodiment of the coordinate input device in this invention is shown, It is a perspective view which shows the structure of the coordinate input device provided with four imaging units, and a coordinate input system. (A) is sectional drawing which shows the optical path of propagation light when a finger touches a light-guide plate, (b) is sectional drawing which shows the optical path of propagation light when a light emission pen is touched to a light-guide plate. It is explanatory drawing which shows the signal in each imaging unit when using one finger and one light emitting pen together. It is explanatory drawing which shows the signal in each imaging unit when using two fingers and one light emitting pen together. It is explanatory drawing which shows the signal in each imaging unit when using one finger and two light emitting pens together. 14 shows still another embodiment of the coordinate input device according to the present invention, in which one finger and two light-emitting pens are used in combination in a coordinate input device provided with six image pickup units. It is explanatory drawing which shows the signal in each imaging unit. FIG. 10 shows still another embodiment of the coordinate input device according to the present invention, in the case where one finger and two light-emitting pens are used together in a coordinate input device provided with two imaging units. It is explanatory drawing which shows the signal in each imaging unit. (A) is explanatory drawing which shows the detection condition in an image pick-up element at the time of lighting of a light source unit, (b) is explanatory drawing which shows the detection condition in an image pick-up element at the time of light extinction of a light source unit. It is sectional drawing which shows the structure of the conventional coordinate input system. (A) and (b) are top views which show the structure of the other conventional coordinate input system. (A) is a perspective view which shows the structure of the position detection apparatus as a conventional coordinate input device, (b) is a top view which shows the structure of the principal part of the said position detection apparatus. (A) is a top view which shows the detection principle of the position detection apparatus as the said conventional coordinate input device, (b) is a wave form diagram which shows the optical signal of the light receiving element in the said position detection apparatus. (A) and (b) are the top views which show the structure of the modification in the position detection apparatus as said conventional coordinate input device, and show the lighting control method of a light source.

[Embodiment 1]
An embodiment of the present invention will be described below with reference to FIGS.

(Configuration of coordinate input system)
A configuration of a coordinate input system including the coordinate input device according to the present embodiment will be described with reference to FIGS. 2 and 3A and 3B. FIG. 2 is an exploded perspective view showing the configuration of the coordinate input system. FIG. 3A is a plan view showing the configuration of the coordinate input system, and FIG. 3B is a side sectional view showing the configuration of the coordinate input system. In this specification, the Z direction in FIG. 2 is the front side of the coordinate input system. 2 is the longitudinal direction of the coordinate input system, and the Y direction in FIG. 2 is the short direction of the coordinate input system.

  As shown in FIG. 2, the coordinate input system 1 according to the present embodiment includes a liquid crystal display module 2 as an image display module and a coordinate input device 3 </ b> A provided on the front side of the liquid crystal display module 2. .

  As shown in FIGS. 3A and 3B, the liquid crystal display module 2 has a liquid crystal layer sandwiched between a pair of substrates (not shown), and the liquid crystal molecules of the liquid crystal layer are aligned by applying a voltage to each substrate. And a liquid crystal display panel 2a provided with various electrodes for changing. In the liquid crystal display panel 2a, a desired display is performed by adjusting the amount of light transmitted through the liquid crystal layer of each pixel by changing the orientation of the liquid crystal molecules by applying a voltage between the electrodes. The liquid crystal display panel 2a is supported by the chassis 2b, and a protective glass 2c is provided on the front surface of the liquid crystal display panel 2a. Note that a conventionally known liquid crystal display module can be used as the configuration of the liquid crystal display module 2.

  In the coordinate input system 1, while watching the screen displayed on the liquid crystal display panel 2 a, for example, a finger as a non-light-emitting detection object is placed on the light guide plate 10 of the coordinate input device 3 </ b> A provided on the front side of the liquid crystal display panel 2 a. By making contact, the coordinates of the contact position on the finger are specified, and desired data can be input.

(Configuration of coordinate input device)
Next, the configuration of the coordinate input device 3A provided in the coordinate input system 1 will be described below with reference to FIG. 2, FIG. 3 (a) (b), and FIG. 4 (a) (b) to FIG. Detailed description. 4A is a side view showing the configuration of the coordinate input system 1, and FIG. 4B is an enlarged side view showing the configuration of the edge of the coordinate input system 1. As shown in FIG. FIG. 5 shows a configuration of the coordinate input system 1, and is a cross-sectional view taken along line AA in FIG. FIG. 6 is a plan view showing an irradiation area to the light guide plate 10 in one LED. 7A and 7B are cross-sectional views showing the configuration of the optical coupling member provided between the light guide plate 10 and the LED 4a. FIG. 8 is a perspective view showing an optical path of scattered light when the finger 8 touches the light guide plate 10.

  As shown in FIGS. 2 and 3A and 3B, the coordinate input device 3A includes a light guide plate 10 as a rectangular transparent light guide member and a corner portion of one side of the rectangular light guide plate 10. Imaging units 20 and 30 serving as direction detection means respectively disposed on the light guide unit 10; a light source unit 4A serving as an illumination light source provided on the back side of one side in the longitudinal direction of the light guide plate 10; and guiding light from the light source unit 4A. An optical coupling member 5 coupled to the optical plate 10 and a detection unit 6 as detection means described later are provided. Further, as shown in FIG. 3B, light absorbing members 7 and 7 are provided on the surface of the light guide plate 10 where the light source unit 4A is disposed at the edge and on the front and back sides of the other end. It has been.

  The light guide plate 10 is made of a single rectangular flat plate made of a translucent material, and is disposed on the display surface side of the liquid crystal display panel 2 a in the liquid crystal display module 2. The light guide plate 10 does not have to be a complete rectangle, and as will be described later, through holes 11 are formed in corners, corners are notched, or corners are curved. It may be a substantially quadrangular shape.

  As shown in FIGS. 3A and 3B, the size of the light guide plate 10 is configured such that the periphery of the four sides is larger than the liquid crystal display panel 2a. Thereby, the imaging units 20 and 30 can be disposed on the back side of the light guide plate 10. As a result, an increase in the size of the coordinate input device 3A in the direction of spreading along the contact surface with the light guide plate 10 of the finger 8 described later is suppressed, which contributes to the realization of the compact size of the coordinate input device 3A. The size of the rectangular light guide plate 10 may be, for example, 60 inches diagonal. However, the present invention is not limited to this, and the diagonal line may be larger, for example, 60 inches, 70 inches, 80 inches, or 60 inches or less.

  The thickness of the light guide plate 10 is mainly 1 to 3 mm. However, it may be thicker than this. In the present embodiment, the thickness of the light guide plate 10 is 3 mm, for example. As a material of the light guide plate 10, for example, acrylic is used, and polycarbonate or glass may be used.

  Further, as shown in FIGS. 4 (a) and 4 (b), through holes serving as concave conical optical path conversion portions are provided at two corners of the light guide plate 10 where the imaging units 20 and 30 are disposed. 11 are formed. In addition, in this Embodiment, although the through-hole 11 is comprised by the conical surface shape, this invention is not limited to this, You may be comprised by the hyperboloid shape or the polygonal surface shape. Further, the central portion of the through hole 11 does not necessarily have to penetrate. The slope may be formed up to the middle of the thickness of the light guide plate 10. In this case, the imaging units 20 and 30 are sealed, so that no foreign matter is mixed into the imaging units 20 and 30.

  As shown in FIG. 5, the angle γ formed between the conical wall surface 11a of the through hole 11 and the back surface of the light guide plate 10 is 45 degrees or less, and for example, 30 degrees or 24 degrees is selected. A mirror coating is applied to the conical surface wall surface 11 a in the through hole 11. As a result, as shown in FIG. 5, the optical path of the light propagating through the inside of the light guide plate 10 and reaching the through hole 11 is changed by the through hole 11 below the light guide plate 10, that is, toward the back surface of the light guide plate 10. Let Even if the wall surface 11 a is not mirror-coated, the optical path can be changed below the light guide plate 10 by the conical surface of the through hole 11. In the present embodiment, since the light conversion member is provided as the through hole 11 in the corner portion of the light guide plate 10, the light conversion member is prevented from protruding from the light guide plate 10.

  Next, the imaging units 20 and 30 are disposed immediately below the conical surface through holes 11 at two corners of the light guide plate 10. Thereby, the imaging units 20 and 30 have a structure that does not protrude above the surface of the light guide plate 10.

  In the coordinate input device 3 </ b> A of the present embodiment, the imaging units 20 and 30 are provided at two corners of the light guide plate 10 that are separated from each other. However, in the present invention, the installation location of the imaging units 20 and 30 is not necessarily limited to the corner portion. For example, imaging units 20 and 30 are provided in at least two locations on one first edge along the longitudinal direction of the light guide plate 10, and the other of the other edges of the light guide plate 10 facing the first edge. It can be assumed that the imaging units 40 and 50 are provided in at least two places on the second edge. This is because the triangulation method requires at least two direction detection means, and therefore, it is necessary to provide at least two or more imaging units 20 and 30.

  As shown in FIG. 5, the imaging unit 20 includes a lens 21, a visible light cut filter 22, and an imaging element 23. Similarly, the imaging unit 30 includes a lens 31, a visible light cut filter 32, and an imaging element 33 as shown in FIG. Therefore, the light incident on the imaging units 20 and 30 is first condensed by the lenses 21 and 31, and then the visible light is blocked by the visible light cut filters 22 and 32 and received by the imaging elements 23 and 33. The In the image sensors 23 and 33, the received light is photoelectrically converted to form an image. This point will be described later. The arrangement positions of the visible light cut filters 22 and 32 may be on the front side of the lenses 21 and 31, that is, on the light guide plate 10 side.

  In addition, the image pickup devices 23 and 33 according to the present embodiment are formed of, for example, a two-dimensional image sensor. However, the image sensor is not necessarily limited to two dimensions, and may be a one-dimensional image sensor. Alternatively, a CMOS (Complementary Metal Oxide Semiconductor) camera may be used.

  The light receiving surfaces of the image sensors 23 and 33 are arranged so as to be parallel to the surface of the light guide plate 10.

  The imaging units 20 and 30 are connected to the light guide plate 10 and have a structure in which light that does not propagate through the light guide plate 10 is not coupled to the imaging elements 23 and 33.

  Next, the light source unit 4A provided at the edge of one side in the longitudinal direction of the light guide plate 10 has a plurality of LEDs (Light Emitting Diodes) 4a arranged in series as shown in FIG. Each LED 4a emits light such as infrared light. However, it is not necessarily limited to infrared light, and may be visible light or ultraviolet light. Further, it is not always necessary to use the LED 4a, and it is preferable to use a semiconductor laser (laser diode: LD). This is because LEDs have a wider emission spectrum width than semiconductor lasers.

  Here, in the present embodiment, the light source unit 4 </ b> A is provided at the edge of one side of the light guide plate 10 in the longitudinal direction. That is, in the coordinate input device 3 </ b> A of the present embodiment, the imaging units 20 and 30 and the light source unit 4 </ b> A are provided on one first edge along the longitudinal direction of the light guide plate 10. In this case, since both the light source unit 4A and the imaging units 20 and 30 are provided on the back side of the light guide plate 10, the light source unit 4A is configured so that the imaging units 20 and 30 do not overlap with each other. 20 and the imaging unit 30. Further, as shown in FIG. 5, the light source unit 4 </ b> A is provided at the outer peripheral end of the light guide plate 10 as compared with the imaging unit 20. Therefore, in the imaging units 20 and 30, the direct light from the light source unit 4A does not enter the signal detection effective area of the imaging units 20 and 30.

  As described above, the light source unit 4 </ b> A is preferably provided at the first edge of one side along the longitudinal direction of the light guide plate 10. The reason for this is that, as shown in FIG. 6, the LED 4 a provided on the side along the longitudinal direction of the light guide plate 10 is provided at the edge of the side along the short direction of the light guide plate 10. This is because the reach of the light of the LED 4a in the light guide plate 10 is short. That is, this increases the amount of light from the light source unit 4A and also reduces the distance from the finger 8 in contact with the light guide plate 10 to the imaging units 20 and 30, so that the light from the finger 8 in contact with the light guide plate 10 can be reduced. This is because the detection intensity of the imaging units 20 and 30 in the scattered light is increased.

  Here, when the scattered light from the finger 8 is detected by the imaging devices 23, 33, etc., it is necessary to increase the output of the scattered light from the imaging devices 23, 33, etc. as much as possible. For this purpose, it is preferable that the amount of propagating light from the LED 4a inside the light guide plate 10 is larger. Therefore, as shown in FIG. 6, the radiation angle δ of one LED 4a is made small. This is because when the radiation angle δ of the LED 4a is large, the light amount density of the irradiation region in one LED 4a decreases.

  In the present embodiment, the light source unit 4 </ b> A is disposed on the back side of the light guide plate 10. In this case, if the light of each LED 4a of the light source unit 4A is vertically incident on the light guide plate 10, the incident light does not guide the inside of the light guide plate 10 and passes through the front surface of the light guide plate 10 as it is. Go. Therefore, in the present embodiment, as shown in FIG. 2, an optical coupling member 5 is provided between the light guide plate 10 and the light source unit 4A, and as shown in FIGS. Light from the 4A LEDs 4a is incident on the light guide plate 10 through the optical coupling member 5 at an angle.

  Specifically, as shown in FIG. 7A, the optical coupling member 5 may be composed of, for example, a triangular prism 5a. The prism 5a can be bonded to the light guide plate 10 using, for example, a double-sided tape 5b or an adhesive. Then, by adhering the LED 4a to the inclined surface of the prism 5a, light can be incident obliquely on the light guide plate 10 as shown in FIG.

  As shown in FIG. 7B, a bullet-type LED 4a can be used as the LED 4a. In this case, as the optical coupling member 5, a transparent block 5 c that can obliquely fix the bullet-type LED 4 a with respect to the light guide plate 10 can be used. This also allows light to enter the light guide plate 10 at an angle.

  Next, as shown in FIG. 8, the coordinate input device 3A is provided with a detection unit 6 as detection means. The detection unit 6 detects outputs from the image pickup devices 23 and 33 based on light scattering by the finger 8 and obtains coordinates of a contact position of the finger 8 on the surface of the light guide plate 10. Specifically, it consists of a CPU.

  In addition, light absorbing members 7 and 7 are provided on the first edge of the light guide plate 10 so as not to overlap the light source unit 4A and the imaging units 20 and 30. The light absorbing members 7 and 7 are formed by sticking a high light-shielding film made of, for example, a black polyester film or the like to the light guide plate 10 so that the reflected light at the end of the light guide plate 10 returns to the opposite end. So that the reflected light is absorbed.

  Here, in the coordinate input system 1 of the present embodiment, for example, the finger 8 is used as the non-light emitting target, and for example, the light emitting pen 9 is used as the light emitting target. However, the non-light emitting detection object is not necessarily limited to the finger 8 and may be a non-light emitting detection object such as a bar-shaped touch pen.

(Principle of coordinate detection of non-luminous object in coordinate input device)
First, regarding the coordinate detection principle when the finger 8 as the non-light-emitting detection object is brought into contact with the light guide plate 10 to the coordinate input device 3A having the above-described configuration, FIGS. 5, 8 and 9A, 9B are described. ) And FIGS. 10 (a) and 10 (b). FIG. 9A is a plan view showing the detection principle of the coordinate input device 3A, and FIG. 9B is a waveform diagram showing an optical signal of the image sensor in the imaging unit of the coordinate input device 3A. FIG. 10A is a plan view showing a contact position when a finger is brought into contact with various places on the surface of the light guide plate, and FIG. 10B shows a detection image of the image sensor corresponding to the contact position of the finger. It is a wave form diagram which shows the relationship between the pixel number which appears and signal strength.

  First, in the coordinate input device 3A, as shown in FIG. 5, light is incident on the light guide plate 10 obliquely from a plurality of LEDs 4a of the light source unit 4A provided along at least one edge of the light guide plate 10. .

  As shown in FIG. 5, the light incident on the light guide plate 10 is guided as propagating light to the entire inner surface of the light guide plate 10. That is, light repeats total reflection inside the light guide plate 10 due to the difference between the refractive index of the light guide plate 10 and the refractive index of air. The totally reflected light is emitted from the end face of the light guide plate 10. The light that is reflected by the end face of the light guide plate 10 and returned is absorbed by the light absorbing members 7 and 7 on the front and back surfaces of the light guide plate 10 and does not return to the imaging units 20 and 30 side.

Here, as shown in FIG. 5, when the finger 8 is brought into contact with, or touched with, the surface of the light guide plate 10, the total reflection condition in the light guide plate 10 is broken, and the finger 8 passes through the light guide plate 10 having the refractive index n. Part of the infrared light that is guided is scattered. Of this scattered light, the propagation angle θ _P in the light guide plate 10 is
sin (90 ° −θ _P )> 1 / n
The light beam satisfying the conditions shown in (2) repeats reflection on the front and back surfaces of the light guide plate 10 and travels in the light guide plate 10.

  As shown in FIG. 8, infrared light that is scattered light of the finger 8 is diffused radially with respect to the two-dimensional plane of the light guide plate 10 and propagates in the light guide plate 10. A part of the propagation light 13a / 14a of the luminous flux is also guided to the wall surfaces 11a / 11a of the conical through holes 11/11, and the reflected light of the wall surfaces 11a / 11a is captured by the imaging units 20/30. The light is received at. Specifically, the reflected light of the wall surfaces 11a and 11a of the through holes 11 and 11 is collected by the lenses 21 and 31 in the imaging units 20 and 30, and then passes through the visible light cut filters 22 and 32. Finally, the light is received by the image sensors 23 and 33. As a result, as shown in FIG. 9B, a light emission peak appears at the pixel number in each of the image sensors 23 and 33. Therefore, the detection unit 6 converts the pixel number in each image obtained from each of the image sensors 23 and 33 into an angle, so that the light guide plate 10 at the location where the finger 8 is in contact as shown in FIG. Angles α and β, which are viewing angles from the imaging units 20 and 30 in the two-dimensional plane, are obtained.

For example, as shown in FIG. 10A, when the finger 8 is brought into contact with the points P ₁ to P ₉ on the light guide plate 10, the image pickup device 23 of the image pickup unit 20 has the image pickup device 23 shown in FIG. As shown, each peak appears at the position of the pixel number corresponding to the points P ₁ to P ₉ . By converting this pixel number into an angle, the angles of the points P ₁ to P ₉ can be obtained. In FIG. 10B, it can be roughly seen that the pixel number 100≈angle 80 degrees, the pixel number 200≈angle 60, the pixel number 300≈angle 40 degrees, and the pixel number 400≈angle 20 degrees.

(Calculation method of 2D coordinate position)
Next, a method for calculating the two-dimensional coordinate position of the light guide plate 10 at the location where the finger 8 is in contact will be described with reference to FIGS. This processing is performed by the detection unit 6. Here, FIG. 11A is a perspective view illustrating an imaging state of the imaging unit 20 in the coordinate input device 3A, and FIG. 11B is a plan view illustrating an image of the imaging element 23 of the imaging unit 20. . 11A and 11B, only the imaging unit 20 will be described, but the same processing is performed in the imaging unit 30 as well.

  As shown in FIG. 5 and FIG. 11A, the light incident on the imaging unit 20 passes through the lens 21 and forms a linear image 25 on the imaging device 23. The position of the linear image 25 varies depending on the position of the finger 8, and the angle α formed between the propagation light 13 a and one side of the light guide plate 10 is obtained by analyzing the acquired image of the image sensor 23. Similarly, a linear image 25 is formed on the image pickup device 33 through the lens 31 by the light incident on the image pickup unit 30. Then, by analyzing the acquired image of the image sensor 33, an angle β formed by the propagation light 14a and one side of the light guide plate 10 is obtained. Based on the angles α and β, the position coordinates of the point touched by the finger 8 are obtained using triangulation.

Specifically, in FIG. 11 (a), the time the finger 8 is in the position of point P _1, as shown in FIG. 11 (b), the linear image 25 is formed. Also, the fingers 8 when moved to the position of the point P _2, the image 27 of the line shape is formed.

  When the light from the light source unit 4A is irradiated, when the finger 8 is not in contact with the light guide plate 10, no change occurs in the acquired images of the image sensors 23 and 33. On the other hand, when the finger 8 comes into contact with the light guide plate 10 and scattered light is generated, the propagation lights 13a and 14a in a part of the light flux are guided to the imaging elements 23 and 33, and are applied to the imaging surfaces of the imaging elements 23 and 33. A linear image is formed, and a linear image 25 appears on the acquired image.

The position of the linear image 25 shown in FIG. 11B changes depending on the position of the contact point on the finger 8, and when the position of the contact point on the finger 8 is changed, the linear image 25 becomes linear. It changes like an image 27. The trajectories of the linear images 25 and 27 have a fan shape 26 indicated by a one-dot chain line. The inclination angle α ₁ ′ of the line segment connecting the fan-shaped center and the linear image 25 (with the center of the circular arc as the rotation center) is the line segment connecting the finger 8 and the image pickup device 23 and the light guide plate 10 described above. The angle is the same as the angle α ₁ formed by one side. Therefore, the inclination angle α ₁ ′ is obtained from the acquired image of the image sensor, and the angle α ₁ is obtained from the inclination angle α ₁ ′. Similarly, when the finger 8 moves to the position of the point P _2, a linear image 27 is formed, and the angle α ₂ is obtained by obtaining the inclination angle α ₂ ′ of the linear image 27.

  Similarly, for the image sensor 33, 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 finger 8 and the image sensor 33 and the certain side of the light guide plate 10 is obtained.

The distance between the image sensor 23 and the image sensor 33 is L, the angle of the bright spot obtained by reading the image from the image sensor 23 is α, and the angle of the bright spot obtained by reading the acquired image from the image sensor 23 is When β is defined, 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) ... Relational expression (2)
Satisfied. Solving this, the coordinates (X, Y) of the bright spot are
X = tan β · L / (tan α + tan β) Equation (3)
Y = (tan α · tan β) · L / (tan α + tan β) (4)
The coordinates X and Y of the point where the finger 8 touches can be obtained from the angles α and β obtained as described above and the interval L that can be obtained in advance. Among these, the space | interval L is a space | interval between the image pick-up element 23 and the image pick-up element 33, and is a fixed value. By obtaining the angles α and β, the coordinates X and Y in the coordinate input device 3A can be obtained.

  The distance L between the image sensor 23 and the image sensor 33 is a distance between the optical axis center of the lens 21 and the optical axis center of the lens 31.

  Further, based on the position coordinates of the finger 8 obtained by the above method, the pixel at the position corresponding to the position coordinates of the liquid crystal display panel 2a is driven, and the user visually recognizes the touch position of the finger 8. Is possible. For this purpose, a control unit (not shown) that controls the driving of the liquid crystal display panel 2a may acquire information on the position coordinates obtained by the detection unit 6 and drive the liquid crystal display panel 2a based on the information.

(Coordinate detection principle of the object to be detected in the coordinate input device)
Next, in the present embodiment, it is possible to detect the coordinates of the contact position of the light-emitting pen 9 even when the light-emitting pen 9 as the light-emitting detection target is in contact with the light guide plate 10 in the coordinate input device 3A having the above configuration. It has become. Hereinafter, the configuration of the light-emitting pen 9 and the principle of coordinate detection when the light-emitting pen 9 as the light-emitting detection target is in contact with the light guide plate 10 in the coordinate input device 3A having the above-described configuration will be described with reference to FIGS. This will be described below. FIG. 12 is a plan view showing the configuration of the light-emitting pen 9 of the present embodiment. FIG. 13 shows the configuration of the coordinate input system, and is a cross-sectional view taken along line AA in FIG. In FIG. 12, for convenience of explanation, a part of the housing is removed to expose the internal structure. FIG. 14 is a perspective view showing an optical path of propagating light when a light emitting pen is touched on the light guide plate.

(Structure of luminous pen)
First, the configuration of the light-emitting pen 9 will be described with reference to FIG. The light emitting pen 9 is an operation member called a so-called touch pen or stylus pen.

  As shown in FIG. 12, the light-emitting pen 9 includes a light-emitting element LD that emits light and a light guide plate 10 that emits light emitted from the light-emitting element LD from the tip of the light-emitting pen 9. A light emitting unit 9b having an introduction unit IS to be introduced into the power source, a power supply device 9c, and a control device 9d are stored. A light scattering member 9e that diffuses light is fixedly attached to the introduction portion IS on the light emitting tip side of the light emitting pen 9.

  The light scattering member 9e is made of a resin containing a light diffusing material. Glass beads can be used as the light diffusion material. Moreover, as said resin, fluororesins, such as polytetrafluoroethylene, or a silicon rubber can be used, for example, and it is preferable to have elasticity. By using an elastic material, when the tip of the light-emitting pen 9, that is, the light scattering member 9e is used in contact with the light guide plate 10 of the coordinate input device 3B, the surface of the light guide plate 10 is not damaged and is slightly touched by contact. The portion can be deformed to increase the contact area with the surface of the light guide plate 10. As a result, the amount of light introduced to the surface of the light guide plate 10 can be increased. That is, the light from the light-emitting pen 9 can be incident in a plurality of radial directions with respect to the depth direction inside the light guide plate 10.

  The light emitting surface of the light scattering member 9e has a curved surface. That is, the light scattering member 9e is generally hemispherical and has a diameter of, for example, 2.5 to 5.5 mm. When the diameter is smaller than 2.5, there is a possibility that the sufficiently diffused light cannot be formed.

  Further, the light scattering member 9 e is configured to be detachable from the light emitting pen 9. Thereby, even when the light scattering member 9e is damaged for some reason or when it deteriorates with time, the use of the light emitting pen 9 can be continued only by replacing the light scattering member 9e.

  As the light emitting element LD, for example, an LED (light emitting diode) that emits light such as infrared light or a semiconductor laser (laser diode: LD) can be used. However, the semiconductor laser is preferable because the emission spectrum width is narrower than that of the LED.

  The power supply device 9c may be configured to include a battery, for example, or may be configured to be rechargeable.

  The control device 9d controls light emission of the light emitting element LD. For example, a mechanism that emits light only when the light emitting element LD contacts the light guide plate 10 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.

  In the light emitting pen 9 configured as described above, the light emitting element LD that receives power from the power supply device 9c emits light of a predetermined wavelength. The light emitted from the light emitting element LD enters the light scattering member 9e through the introduction part IS, and is irregularly reflected by the light diffusing material of the light scattering member 9e and the fine uneven shape. And it is radiate | emitted as diffused light from the light-projection surface of the light-scattering member 9e.

  As described above, the light-emitting pen 9 is provided with the light-emitting portion 9b that emits light, so that light is diffused and emitted from the pen tip. Therefore, when the pen tip of the light-emitting pen 9 comes into contact with the light guide plate 10, part of the infrared light emitted from the pen tip is coupled to the light guide plate 10 and propagates through the light guide plate 10. Since the light emitting pen 9 diffuses and emits light from the pen tip, the light coupled to the light guide plate 10 is guided and propagated while diffusing and radiating the light guide plate 10.

  As shown in FIG. 13, the propagation lights 13 a and 14 a propagating through the light guide plate 10 enter the imaging units 20 and 30 through the through holes 11, respectively. In the imaging units 20 and 30, an angle formed with the imaging units 20 and 30 in the two-dimensional plane of the light guide plate 10 at a location where the light-emitting pen 9 is in contact is obtained from each image obtained from the imaging elements 23 and 33. Thereby, based on the calculation principle of the two-dimensional coordinate described below, the position coordinate in the two-dimensional plane can be obtained with high accuracy.

(Calculation of two-dimensional coordinate position in light-emitting pen)
The two-dimensional coordinates at the location where the light-emitting pen 9 is in contact using the angle formed with the imaging units 20 and 30 in the two-dimensional plane of the light guide plate 10 at the location where the light-emitting pen 9 is in contact as determined above. Calculate the position. The method for calculating the two-dimensional coordinate position at the location where the light-emitting pen 9 is in contact is exactly the same as the method for calculating the two-dimensional coordinate position at the location where the finger 8 is in contact, and thus the description thereof is omitted.

(Coordinate detection method for contact position when using both finger and light-emitting pen)
As shown in FIG. 1, the coordinate input device 3 </ b> A according to the present embodiment is a light guide plate 10 as a light guide member, and an illumination light source that is coupled to an edge of the light guide plate 10 and illuminates the inside of the light guide plate 10. Of light propagating through the light guide plate 10 generated when the light source unit 4A, the finger 8 as the non-light emitting target and the light emitting pen 9 as the light emitting target touch the light guide plate 10. The image pickup units 20 and 30 as at least two direction detection means for detecting directions are provided, and the position coordinates of the contact point are obtained by triangulation based on the detection of the traveling direction of the propagation light by the image pickup units 20 and 30. That is, as shown in FIG. 5, the light introduced from the light source unit 4 </ b> A into the light guide plate 10 is scattered when the finger 8 comes into contact with the light guide plate 10, and the scattered light starts from there. Propagate inside. As shown in FIG. 13, when the light-emitting pen 9 contacts the light guide plate 10, the light that is optically coupled at the contact point propagates inside the light guide plate 10. These lights are imaged by the imaging units 20 and 30 to detect angle information of the contact point.

  By the way, in such a coordinate input device 3A, for example, when both the finger 8 and the light-emitting pen 9 are used, the light-emitting wavelengths of the light source unit 4A of the finger 8 and the light-emitting pen 9 are set in order to separate them. If different filters are provided in the imaging units 20 and 30 to distinguish them, the number of parts increases and the cost increases.

  Therefore, in the present embodiment, the illumination light source lighting control unit 15 as an illumination light source blinking means for periodically blinking the light source unit 4A, and the position of the finger 8 are detected during the lighting period of the light source unit 4A. A detection unit 6 is provided as detection means for detecting the position of the light-emitting pen 9 during the light-off period. Thereby, the illumination light source lighting control unit 15 causes the light source unit 4A to blink periodically. Then, the detection unit 6 detects the position of the finger 8 during the lighting period of the light source unit 4A, and detects the position of the light emitting pen 9 during the extinguishing period of the light source unit 4A.

  That is, the light source unit 4 </ b> A is periodically turned on in synchronization with the control signal from the illumination light source lighting control unit 15. Here, as shown in FIGS. 14A, 14B, 14C, and 14D, the signal from the light emitting pen 9 is always detected by the imaging units 20 and 30, but the signal from the finger 8 is the light source unit. Only the lighting period of 4A is detected. For this reason, by performing signal processing using the synchronization signal, it is possible to separate and detect the signal of the finger 8 and the signal of the light-emitting pen 9 using the common optical system, that is, the imaging units 20 and 30.

  As a result, even if the wavelength of the light source unit 4A and the light emission wavelength of the light-emitting pen 9 are the same, they can be easily distinguished and detected by shifting the detection time. Note that, by setting the blinking cycle in the light source unit 4A to, for example, 100 Hz or more, it can be considered that both are detected substantially at the same time.

  Thereby, for example, erroneous recognition of character input using the light-emitting pen 9 and gesture operation such as reduction, enlargement, and rotation using the finger 8 is eliminated. And it is not necessary to switch between the input mode and the gesture operation mode. It is also possible to use the input of the finger 8 as a character input. Further, the input information of the finger 8 and the input information of the light-emitting pen 9 can be stored as separate information.

  In addition, the light source unit 4A is periodically turned off and used exclusively for input with the light emitting pen 9, while the light source unit 4A is periodically turned on and used exclusively for input of the finger 8. It may be allowed. Further, in an input waiting state, a power saving mode for extending the lighting cycle may be provided.

  Therefore, in the optical coordinate input device 3A using the light guide plate 10, the coordinate positions of both the non-light emitting target object such as the finger 8 and the light emitting target object such as the light emitting pen 9 are determined by one type of light source wavelength. A coordinate input device 3A that can be detected can be provided.

  As described above, in the coordinate input device 3A of the present embodiment, the illumination light source lighting control unit 15 as the illumination light source blinking means for periodically blinking the light source unit 4A as the illumination light source and the lighting period of the light source unit 4A are not used. A detection unit 6 is provided as detection means for detecting the position of the finger 8 as the light emission target and detecting the position of the light emitting pen 9 as the light detection target during the extinction period of the light source unit 4A.

  In the coordinate detection method of the present embodiment, the light source unit 4A is periodically blinked, the position of the finger 8 is detected during the lighting period of the light source unit 4A, and the position of the light-emitting pen 9 is detected during the extinguishing period of the light source unit 4A. I do.

  As a result, even if the light emission wavelength of the light source unit 4A and the light emission wavelength of the light-emitting pen 9 are the same, both can be easily distinguished and detected by shifting the detection time.

  Therefore, in the optical coordinate input device 3 </ b> A using the light guide plate 10, coordinates that can efficiently detect the coordinate positions of both the non-light emitting target body such as the finger 8 and the light emitting target body such as the light emitting pen 9. An input device 3A can be provided.

  The coordinate input system 1 of the present embodiment is a coordinate input system including the coordinate input device 3A of the present embodiment, and includes a liquid crystal display module 2.

  According to the above configuration, the coordinate input device 3 </ b> A is input with the non-light emitting detection object such as the finger 8 and the light emission detection object such as the light emitting pen 9 while viewing the image of the liquid crystal display module 2 as the image display module. It can function as a touch panel. Therefore, in the optical coordinate input device 3A that uses the light guide plate 10, even when applied to a large touch panel, the coordinate positions of both the finger 8 that is a non-light emitting target and the light emitting pen 9 that is a light emitting target. It is possible to provide a coordinate input system 1 including a coordinate input device 3 </ b> A that can detect.

[Embodiment 2]
The following will describe another embodiment of the present invention with reference to FIGS. The configurations other than those described in the present embodiment are the same as those in the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of the first embodiment are given the same reference numerals, and explanation thereof is omitted.

  In the coordinate input device 3A of the first embodiment, as shown in FIG. 1, the imaging units 20 and 30 and the light source unit 4A are provided at one edge portion in the longitudinal direction of the light guide plate 10 made of a rectangle. However, in the coordinate input device 3B of the present embodiment, as shown in FIG. 15, the imaging units 20B, 30B, 40B, and 50B and the light source unit 4A are disposed at two opposing edges in the longitudinal direction of the rectangular light guide plate 10.・ 4B is provided. Then, the light source unit 4A that emits the first wavelength λ1 and the light source unit 4B that emits the second wavelength λ2 are alternately lit by being alternately lit, and the imaging units 20B, 30B, 40B, and 50B. Is different from the coordinate input device 3A of the first embodiment in that it includes optical filters 22B, 32B, 42B, and 52B for identifying the first wavelength λ1 and the second wavelength λ2.

  The configuration of the coordinate input device 3B according to the present embodiment will be described with reference to FIG. FIG. 15 is a perspective view showing the configuration of the coordinate input device 3B.

  As shown in FIG. 15, the coordinate input device 3B has a light source unit 4A as a first illumination light source and a pair of first direction detection means at the first edge of the light guide plate 10 as a light guide member. Units 20 and 30 are provided, and a light source unit 4B as a second illumination light source and a pair of image pickup units 40 as a second direction detection unit are provided on a second edge portion of the light guide plate 10 that faces the first edge portion. 50 is provided. The imaging units 20B and 30B are installed outside the irradiation range of the light source unit 4A, and the imaging units 40B and 50B are installed outside the irradiation range of the light source unit 4B.

  In the present embodiment, the light source units 4A and 4B emit light having different wavelengths. Specifically, the light source unit 4A emits the first wavelength λ1, while the light source unit 4B emits the second wavelength λ2. The first wavelength λ1 of the light source unit 4A can be set to, for example, 830 nm ± 30 nm composed of infrared, while the second wavelength λ2 of the light source unit 4B can be set to, for example, 730 nm ± 30 nm formed of infrared. However, the present invention is not necessarily limited to this, and other wavelength combinations may be used.

  Moreover, in this Embodiment, the light emission pen 9 as a light emission to-be-detected body radiate | emits the light of the same wavelength as any one of the said light source unit 4A or the light source unit 4B. For example, the light-emitting pen 9 uses a laser and emits, for example, 830 nm ± 5 nm which is the range of the first wavelength λ1 of the light source unit 4A.

  Further, in the coordinate input device 3B of the present embodiment, the pair of imaging units 20B and 30B are provided with optical filters 22B and 32B as first illumination light source filters that selectively transmit light from the light source unit 4A. The other pair of imaging units 40B and 50B are provided with optical filters 42B and 52B as second illumination light source filters that selectively transmit light from the light source unit 4B. The light that has passed through the optical filters 22B and 32B is detected by the image sensors 23 and 33, while the light that has passed through the optical filters 42B and 52B is detected by the image sensors 43 and 53.

  Moreover, the illumination light source lighting control unit 15 as the illumination light source blinking unit alternately turns on the light source unit 4A on the first edge and the light source unit 4B on the second edge.

  And the detection part 6 as a detection means is a pair of imaging unit 20B * 30B or imaging unit 40B * 50B of the side in which the light source unit 4A or the light source unit 4B is lit during the lighting period of the light source unit 4A or the light source unit 4B. Is used to detect the position of the finger 8 as a non-light emitting target, while the pair of imaging units 20B and 30B or a pair of second direction detection means is used as a light emitting target. The position of the light emitting pen 9 is detected.

(Coordinate detection method for contact position when using both finger and light-emitting pen)
A coordinate input method in the combined use of the finger 8 and the light emitting pen 9 in the coordinate input device 3B having the above-described configuration will be described below with reference to FIGS. 15, 16A, 16B, and 17. FIG. FIG. 16A is a cross-sectional view showing the propagation light when the finger 8 is brought into contact with the light guide plate 10, and FIG. 16B shows the propagation light when the light emitting pen 9 is brought into contact with the light guide plate 10. It is sectional drawing. FIG. 17 is an explanatory diagram showing signals in the imaging units 20B, 30B, 40B, and 50B when the finger 8 and the light-emitting pen 9 are used in combination.

  First, in the present embodiment, as shown in FIG. 15, the illumination light source lighting control unit 15 synchronizes the light source units 4 </ b> A and 4 </ b> B having different wavelengths on the opposite two sides on the long side of the light guide plate 10 with the control signal. And turn them on alternately.

  16A and 16B, when the light source unit 4A having the first wavelength λ1 emits light, the optical filters 22B and 32B as the first illumination light source filters on the light source unit 4A side are provided. Signals from the finger 8 and the light-emitting pen 9 are detected by the imaging units 20 and 30 provided. The optical filters 22B and 32B transmit the first wavelength λ1 and block the second wavelength λ2.

  At this time, as shown in FIG. 17, in the imaging units 20B and 30B, the signal from the light emitting pen 9 is always detected, but the signal from the finger 8 is detected only during the lighting period of the light source unit 4A. Therefore, for the light-emitting pen 9, the signal of the finger 8 can be reliably detected by performing the signal removal process of the light-emitting pen 9 using the synchronization signal.

  At this time, in the imaging units 40B and 50B, when the light source unit 4B having the second wavelength λ2 emits light, the imaging units 40B including the optical filters 42B and 52B as the second illumination light source filters on the light source unit 4B side. In 50B, since the first wavelength λ1 is cut off and the second wavelength λ2 is transmitted, the signal from the finger 8 is detected. At this time, the signal of the light emitting pen 9 having the first wavelength λ1 and the direct light of the light source unit 4A are blocked by the optical filters 42B and 52B.

  The detection position of the finger 8 can be detected by any of the imaging units 20B, 30B, 40B, and 50B. For example, by adopting a value with a higher detection intensity, a coordinate position with higher reliability can be obtained. Can be requested.

  This makes it possible to separately detect the signal of the finger 8 and the signal of the light-emitting pen 9 using the imaging units 20B, 30B, 40B, and 50B, which are common optical systems. In this case, due to the presence of the optical filters 22B, 32B, 42B, and 52B, the illumination light of the light source units 4A and 4B for detecting the finger 8 is directly incident on the imaging units 40B, 50B, 20B, and 30B on the opposite side. There is no.

  As a result, the light source units 4A and 4B and the imaging units 20B, 30B, 40B, and 50B can be arranged on the two opposing sides of the light guide plate 10, so that multi-touch can be reliably detected.

(Coordinate detection method for contact position when one or the other of a finger and a light-emitting pen is used in combination)
Here, in the coordinate input device 3B of the present embodiment, not only one finger and one light-emitting pen are used together, but one of the fingers and the light-emitting pen is one, and the other is two. Can be used in combination. A method for detecting the coordinate of the contact position in that case will be described with reference to FIG. 15, FIG. 18, and FIG. FIG. 18 is an explanatory view showing a coordinate detection method of a contact position when two fingers 8 and one light-emitting pen 9 are used together. FIG. 19 shows one finger 8 and two light-emitting pens 9. It is explanatory drawing which shows the coordinate detection method of the contact position at the time of using together.

  First, as shown in FIG. 18, a coordinate detection method for a contact position when two fingers 8 and one light-emitting pen 9 are used together will be described.

  First, as shown in FIG. 15, the illumination light source lighting control unit 15 alternately turns on the light source units 4 </ b> A and 4 </ b> B having different wavelengths on opposite long sides of the light guide plate 10 in synchronization with the control signal. .

  In this case, as shown in FIG. 18, when the light source unit 4A having the first wavelength λ1 is emitting light, the fingers 8 and 8 are picked up by the imaging units 20B and 30B including the optical filters 22B and 32B on the light source unit 4A side. And signals from the light emitting pen 9 are detected.

  Here, the optical filters 22B and 32B transmit the first wavelength λ1 and block the second wavelength λ2. Therefore, in the imaging units 20B and 30B, the signal from the light emitting pen 9 is always detected, but the signal from the fingers 8 and 8 is detected only during the lighting period of the light source unit 4A. For this reason, with respect to the light-emitting pen 9, the signal of the finger 8 or 8 can be reliably detected by performing the signal removal processing of the light-emitting pen 9 using the synchronization signal.

  On the other hand, in the imaging units 40B and 50B, when the light source unit 4B having the second wavelength λ2 emits light, the imaging units 40B and 50B including the optical filters 42B and 52B on the light source unit 4B side change the first wavelength λ1. Since the signal is blocked and the second wavelength λ2 is transmitted, signals from the fingers 8 and 8 are detected. At this time, the signal of the light emitting pen 9 having the first wavelength λ1 and the direct light of the light source unit 4A are blocked by the optical filters 42B and 52B.

  The detection positions of the fingers 8 and 8 can be detected by any of the imaging units 20B, 30B, 40B, and 50B. For example, by adopting the value with the larger detection intensity, the reliability is higher. The coordinate position can be obtained.

  This makes it possible to separate and detect the signals of the fingers 8 and 8 and the signal of the light-emitting pen 9 using the imaging units 20B, 30B, 40B, and 50B, which are common optical systems. In this case, due to the presence of the optical filters 22B, 32B, 42B, and 52B, the illumination light of the light source units 4A and 4B for detecting the fingers 8 and 8 is directly incident on the imaging units 40B, 50B, 20B, and 30B on the opposite side. There is nothing to do.

  As a result, the light source units 4A and 4B and the imaging units 20B, 30B, 40B, and 50B can be arranged on the two opposing sides of the light guide plate 10, so that multi-touch can be reliably detected.

  Next, as shown in FIG. 19, a coordinate detection method for a contact position when one finger 8 and two light-emitting pens 9 and 9 are used together will be described. In this case, one light emitting pen 9 emits the first wavelength λ1, while the other light emitting pen 9 emits the second wavelength λ2. Hereinafter, the light-emitting pen 9 (λ1) or the light-emitting pen 9 (λ2) will be described.

  First, as shown in FIG. 15, the illumination light source lighting control unit 15 alternately turns on the light source units 4 </ b> A and 4 </ b> B having different wavelengths on opposite long sides of the light guide plate 10 in synchronization with the control signal. .

  In this case, as shown in FIG. 19, when the light source unit 4A having the first wavelength λ1 emits light, the image pickup units 20B and 30B including the optical filters 22B and 32B on the light source unit 4A side emit light. Signals from the pens 9 (λ1) and 9 (λ2) are detected.

  Here, the optical filters 22B and 32B transmit the first wavelength λ1 and block the second wavelength λ2. Therefore, in the imaging units 20B and 30B, the signal from the light emitting pen 9 (λ1) is always detected, but the signal from the finger 8 is detected only during the lighting period of the light source unit 4A. For this reason, with respect to the light-emitting pen 9 (λ1), the signal of the finger 8 can be reliably detected by performing the signal removal processing of the light-emitting pen 9 (λ1) using the synchronization signal.

  On the other hand, in the imaging units 40B and 50B, when the light source unit 4B having the second wavelength λ2 emits light, the imaging units 40B and 50B including the optical filters 42B and 52B on the light source unit 4B side change the first wavelength λ1. Since the light is blocked and the second wavelength λ2 is transmitted, signals from the light-emitting pen 9 (λ2) and the finger 8 are detected. Therefore, for the light-emitting pen 9 (λ2), the signal of the finger 8 can be reliably detected by performing the signal removal process of the light-emitting pen 9 (λ2) using the synchronization signal.

  At this time, the signal of the light emitting pen 9 (λ1) having the first wavelength λ1 and the direct light of the light source unit 4A are blocked by the optical filters 42B and 52B.

  The detection position of the finger 8 can be detected by any of the imaging units 20B, 30B, 40B, and 50B. For example, by adopting a value with a higher detection intensity, a coordinate position with higher reliability can be obtained. Can be requested.

  Thereby, it is possible to separately detect the signal of the finger 8 and the signal of the light emitting pens 9 (λ1) and 9 (λ2) using the imaging units 20B, 30B, 40B, and 50B, which are common optical systems. In this case, due to the presence of the optical filters 22B, 32B, 42B, and 52B, the illumination light of the light source units 4A and 4B for detecting the finger 8 is directly incident on the imaging units 40B, 50B, 20B, and 30B on the opposite side. There is no.

  As a result, the light source units 4A and 4B and the imaging units 20B, 30B, 40B, and 50B can be arranged on the two opposing sides of the light guide plate 10, so that multi-touch can be reliably detected.

  In addition, by such a method, two light emitting pens 9 (λ1) and 9 (λ2) and three fingers 8 can be detected.

  As described above, the coordinate input device 3B according to the present embodiment includes the light source units 4A and 4B having different wavelengths on the first edge and the second edge, which are two opposite sides of the light guide plate 10, and these. Light up alternately. For example, when the light source unit 4A having the first wavelength λ1 emits light, the optical filters 22C and 32C (transmitting the first wavelength λ1 and transmitting the second wavelength λ2) as the first illumination light source filter on the light source unit 4A side. In the imaging units 20B and 30B serving as a pair of first direction detecting means provided with a blocking function, the positions of the finger 8 as the non-light emitting target and the light emitting pen 9 as the light emitting target are detected. The signal from the light-emitting pen 9 is always detected, but the signal from the finger 8 is detected only during the lighting period of the light source unit 4A. As a result, the signal of the finger 8 can be reliably detected by performing the signal removal processing of the light emitting pen 9.

  On the other hand, when the light source unit 4B serving as the second illumination light source having the second wavelength λ1 emits light, the optical filters 42B and 52B serving as the second illumination light source filter on the light source unit 4B side (blocking the first wavelength λ1) The position of the finger 8 is detected by the imaging units 40 </ b> B and 50 </ b> B as a pair of second direction detection means having a transmission of the second wavelength λ <b> 2. Signals from the light emitting pen 9 and direct light from the light source unit 4A are blocked by the optical filters 42B and 52B. In this case, the signal of the light emitting pen 9 (λ2) can be detected by using the light emitting pen 9 (λ2) having the second wavelength λ2.

  As a result, the common optical system, that is, the light source unit 4A, the optical filters 22B and 32B, and the pair of imaging units 20B and 30B, or the light source unit 4B, the optical filters 42B and 52B, and the pair of imaging units 40B and 50B are used. It becomes possible to separately detect the signal and the signal of the light-emitting pen 9. In this case, due to the operational effects of the optical filters 22B, 32B, 42B, and 52B, the light from the finger 8 does not directly enter the pair of imaging units 40B and 50B on the opposite side.

  Therefore, the light source unit 4A, the optical filters 22B and 32B, and the pair of imaging units 20B and 30B, or the light source unit 4B, the optical filters 42B and 52B, and the first edge and the second edge, which are two opposite sides, Since the pair of imaging units 40B and 50B are arranged, it becomes possible to reliably detect multi-touch between the finger 8 and the light-emitting pen 9.

  In the coordinate detection method of the present embodiment, the light source unit 4A is periodically blinked, the position of the finger 8 is detected during the lighting period of the light source unit 4A, and the position of the light-emitting pen 9 is detected during the extinguishing period of the light source unit 4A. I do.

  As a result, even if the light emission wavelength of the light source unit 4A and the light emission wavelength of the light-emitting pen 9 are the same, both can be easily distinguished and detected by shifting the detection time.

  Therefore, in the optical coordinate input device 3B that uses the light guide plate 10, the coordinates that can efficiently detect the coordinate positions of both the non-light emitting target such as the finger 8 and the light emitting target such as the light emitting pen 9 are detected. An input device 3B can be provided.

  The coordinate input system 1 according to the present embodiment is a coordinate input system including the coordinate input device 3B according to the present embodiment, and includes a liquid crystal display module 2.

  According to the above configuration, the coordinate input device 3B is input with the non-light emitting detection object such as the finger 8 and the light emission detection object such as the light emitting pen 9 while viewing the image of the liquid crystal display module 2 as the image display module. It can function as a touch panel. Therefore, in the optical coordinate input device 3B that uses the light guide plate 10, even when applied to a large touch panel, the coordinate positions of both the finger 8 that is a non-light emitting target and the light emitting pen 9 that is a light emitting target. It is possible to provide the coordinate input system 1 including the coordinate input device 3B that can detect the above.

[Embodiment 3]
The following will describe another embodiment of the present invention with reference to FIG. The configurations other than those described in the present embodiment are the same as those in the first embodiment and the second embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of Embodiment 1 and Embodiment 2 are given the same reference numerals, and explanation thereof is omitted.

  As shown in FIG. 20, the coordinate input device 3C of the present embodiment is different in that six imaging units 20B, 25B, 30B, 40B, 45B, and 50B are provided.

  The configurations of the imaging units 25B and 45B are the same as the configurations of the imaging units 20B, 30B, 40B, and 50B. That is, the imaging unit 25B has an optical filter that selectively transmits the first wavelength λ1 as in the imaging units 20B and 30B, while the imaging unit 45B has the second wavelength as in the imaging units 40B and 50B. An optical filter that selectively transmits λ2 is provided.

  A coordinate detection method for a contact position when one finger 8 and two light-emitting pens 9 and 9 are used together will be described using the coordinate input device 3C of the present embodiment. In this case, one light emitting pen 9 emits the first wavelength λ1, while the other light emitting pen 9 emits the second wavelength λ2. Hereinafter, the light-emitting pen 9 (λ1) or the light-emitting pen 9 (λ2) will be described.

  First, as shown in FIG. 15, the illumination light source lighting control unit 15 alternately turns on the light source units 4 </ b> A and 4 </ b> B having different wavelengths on opposite long sides of the light guide plate 10 in synchronization with the control signal. .

  In this case, as shown in FIG. 20, when the light source unit 4A having the first wavelength λ1 emits light, the imaging units 20B, 25B, and 30B including the optical filters 22B and 32B on the light source unit 4A side are used. 8 and the light-emitting pens 9 (λ1) and 9 (λ2) are detected.

  Here, the optical filters 22B, 32B, etc. transmit the first wavelength λ1 and block the second wavelength λ2. Therefore, in the imaging units 20B, 25B, and 30B, the signal from the light emitting pen 9 (λ1) is always detected, but the signal from the finger 8 is detected only during the lighting period of the light source unit 4A. For this reason, with respect to the light-emitting pen 9 (λ1), the signal of the finger 8 can be reliably detected by performing the signal removal processing of the light-emitting pen 9 (λ1) using the synchronization signal.

  On the other hand, in the imaging units 40B, 45B, and 50B, when the light source unit 4B having the second wavelength λ2 emits light, in the imaging units 40B, 45B, and 50B including the optical filters 42B and 52B on the light source unit 4B side, Since the first wavelength λ1 is blocked and the second wavelength λ2 is transmitted, signals from the light emitting pen 9 (λ2) and the finger 8 are detected. Therefore, for the light-emitting pen 9 (λ2), the signal of the finger 8 can be reliably detected by performing the signal removal process of the light-emitting pen 9 (λ2) using the synchronization signal.

  At this time, the signal of the light emitting pen 9 (λ1) having the first wavelength λ1 and the direct light of the light source unit 4A are blocked by the optical filters 42B and 52B.

  The detection position of the finger 8 can be detected by any of the imaging units 20B, 25B, 30B, 40B, 45B, and 50B. For example, by adopting the value with the higher detection intensity, the reliability can be improved. Can be obtained.

  Thus, the signal of the finger 8 and the signal of the light emitting pen 9 (λ1) and 9 (λ2) can be separately detected using the imaging units 20B, 25B, 30B, 40B, 45B, and 50B, which are common optical systems. It becomes possible. In this case, due to the presence of the optical filters 22B, 32B, 42B, 52B, etc., the imaging units 40B, 45B, 50B, 20B, 25B, 30B on the side facing the illumination light of the light source units 4A, 4B for detecting the finger 8 are opposed. There is no direct incidence.

  As a result, the light source units 4A and 4B and the imaging units 20B, 25B, 30B, 40B, 45B, and 50B can be arranged on two opposite sides of the light guide plate 10, so that multi-touch can be reliably detected. become.

  In addition, by such a method, two light emitting pens 9 (λ1) and 9 (λ2) and up to five fingers 8 can be detected.

[Embodiment 4]
The following will describe still another embodiment of the present invention with reference to FIGS. The configurations other than those described in the present embodiment are the same as those in the first embodiment and the second embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of Embodiment 1 and Embodiment 2 are given the same reference numerals, and explanation thereof is omitted.

  The coordinate input device 3D of the present embodiment is the same as the coordinate input device 3A described in the first embodiment, except that the imaging units 20 and 30 have the optical filters 22B, 32B, and 42B described in the second and third embodiments. The difference is that the imaging units 20C and 30C are provided with optical filters 22C and 32C as merge filters different from 52B.

  That is, the imaging units 20C and 30C of the coordinate input device 3D of the present embodiment are provided with optical filters 22C and 32C as shown in FIG. 21, and the optical filters 22C and 32C are as shown in FIG. A central circular region S1 as a selection region indicated by hatching and an outer circular region S2 as a non-selection region that is an outer region of the central circular region S1 are provided. The central circular region S1 is a filter that transmits the first wavelength λ1 and blocks the second wavelength λ2. Further, the outer circular region S2 transmits both the first wavelength λ1 and the second wavelength λ2.

  A coordinate detection method for the contact position when one finger 8 and two light-emitting pens 9 and 9 are used together will be described using the coordinate input device 3D of the present embodiment. In this case, one light emitting pen 9 emits the first wavelength λ1, while the other light emitting pen 9 emits the second wavelength λ2. Hereinafter, the light-emitting pen 9 (λ1) or the light-emitting pen 9 (λ2) will be described.

  First, as shown in FIG. 1, the illumination light source lighting control unit 15 periodically turns on the light source unit 4A provided on one side of the long side of the light guide plate 10 in synchronization with the control signal.

  Here, the optical filters 22C and 32C transmit the first wavelength λ1 and block the second wavelength λ2 inside the central circular region S1. In the outer circular region S2, both the first wavelength λ1 and the second wavelength λ2 are transmitted. Therefore, in the central circular region S1 in the optical filters 22C and 32C, the signal from the light emitting pen 9 (λ1) is always detected, but the signal from the finger 8 is detected only during the lighting period of the light source unit 4A. On the other hand, in the outer circular region S2 in the optical filters 22C and 32C, signals from the light emitting pens 9 (λ1) and 9 (λ2) are always detected, but signals from the finger 8 are detected only during the lighting period of the light source unit 4A. Is done.

  At this time, in the image pickup devices 23 and 33 in the image pickup units 20 and 30, when the light source unit 4A is turned on and off, a line is displayed on a part of the fan shape as shown in FIGS. 22 (a) and 22 (b), respectively. Then, it is converted and displayed on angle coordinates.

  Thereby, the light-emitting pen 9 (λ1) is always detected. Further, the light emitting pen 9 (λ2) is not detected from the central circular area S1. Furthermore, the finger 8 is detected only when the light source unit 4A is turned on.

  As a result, when the above conditions are taken into consideration, it is possible to identify and detect all contact positions of the light-emitting pens 9 (λ1) and 9 (λ2) and the finger 8.

  In the present embodiment, by devising the optical filters 22C and 32C of the imaging units 20C and 30C, all contact positions of the light-emitting pens 9 (λ1) and 9 (λ2) and the finger 8 are identified with a simple configuration. Can be detected.

  As described above, in the coordinate input device 3D of the present embodiment, the light emission target is the first light emission target to emit light having the same first wavelength λ1 as the light emitted from the light source unit 4A as the illumination light source. And a light-emitting pen 9 (λ2) as a second light-emitting target to emit light having a second wavelength λ2 different from the light having the first wavelength λ1, and at least The imaging units 20B and 30B as the two direction detecting means are configured to transmit a central circular region S1 as a selection region that selectively transmits light having the first wavelength λ1, light having the first wavelength λ1, and light having the second wavelength λ2. Optical filters 22C and 32C as merge filters divided into a non-circular region S2 as a non-selection region that transmits both are provided.

  Thereby, in at least two imaging units 20B and 30B, only one optical filter 22C and 32C are provided, respectively, and one finger 8 as a non-light emitting detection object, a light emitting pen 9 (λ1), and a light emitting pen 9 are provided. A coordinate position with (λ2) can be detected.

  Therefore, since the direction detection means is not increased, the increase in the number of parts and the increase in cost are suppressed, and the combined use of one finger 8 and two light-emitting pens 9 (λ1) and light-emitting pens 9 (λ2) is used. A coordinate input device 3D that can be provided can be provided.

  In the coordinate detection method of the present embodiment, the light source unit 4A is periodically blinked, the position of the finger 8 is detected during the lighting period of the light source unit 4A, and the light emitting pen 9 (λ1) is turned off during the lighting period of the light source unit 4A. In addition, the position of the light emitting pen 9 (λ2) is detected.

  As a result, even if the light emission wavelength of the light source unit 4A and the light emission wavelength of the light emitting pen 9 (λ1) are the same, they can be easily distinguished and detected by shifting the detection time.

  Accordingly, in the optical coordinate input device 3D that uses the light guide plate 10, both the non-light emitting detection object such as the finger 8 and the light emission detection objects such as the light emission pen 9 (λ1) and the light emission pen 9 (λ2). It is possible to provide a coordinate input device 3D that can efficiently detect the coordinate position of

  The coordinate input system 1 of the present embodiment is a coordinate input system including the coordinate input device 3D of the present embodiment, and includes a liquid crystal display module 2.

  According to the above-described configuration, the coordinate input device 3D is configured such that the light emitting pen 9 (λ1) and the light emitting pen 9 (λ2), the non-light emitting detection object such as the finger 8 while viewing the image of the liquid crystal display module 2 as the image display module It can be made to function as a touch panel which inputs with a light emission detected object, such as. Therefore, even when the optical coordinate input device 3D using the light guide plate 10 is applied to a large-sized touch panel, the finger 8 that is a non-light emitting target, the light emitting pen 9 (λ1) that is a light emitting target, and the light emission. The coordinate input system 1 including the coordinate input device 3D that can detect both coordinate positions of the pen 9 (λ2) can be provided.

  It should be noted that the present invention is not limited to each embodiment, and various modifications are possible within the scope shown in the claims, and obtained by appropriately combining the technical means disclosed in each embodiment. Such embodiments are also included in the technical scope of the present invention.

  The present invention can be applied to an optical coordinate input device, a coordinate detection method, and a coordinate input system that use a light guide member that can be used in combination with a finger and a light-emitting pen. Further, the coordinate input device can be applied to both a finger type and a touch pen type. Furthermore, the coordinate input system can be applied to a personal computer, a television, a white board, a tablet terminal, and the like.

1 Coordinate input system 2 Liquid crystal display module (image display module)
2a Liquid crystal display panel 3A Coordinate input device 3B Coordinate input device 3C Coordinate input device 3D Coordinate input device 4A Light source unit (illumination light source, first illumination light source)
4B Light source unit (illumination light source, second illumination light source)
4a LED
5 Optical coupling member 6 Detection part (detection means)
7 Light-absorbing member 8 Finger (non-light-emitting target)
9 Light-emitting pen (light-emitting detection target)
9 (λ1) Luminescent pen (first illuminant to be detected)
9 (λ2) Light-emitting pen (second light-emitting detection target)
10 Light guide plate (light guide member)
11 Through-hole 11a Wall surface 13a Propagating light 14a Propagating light 15 Illumination light source lighting control unit (illumination light source blinking means)
20 imaging unit (direction detection means, first direction detection means)
21 Lens 22 Visible Light Cut Filter 22B Optical Filter (First Illumination Light Source Filter)
22C optical filter (merged filter)
23 Image sensor 25B Image pickup unit (direction detection means, first direction detection means)
30 imaging unit (direction detection means, first direction detection means)
31 Lens 32 Visible Light Cut Filter 32B Optical Filter (First Illumination Light Source Filter)
32C optical filter (merged filter)
33 Image sensor 40B Image pickup unit (direction detection means, second direction detection means)
42B Optical filter (filter for second illumination light source)
43 Image sensor 45B Image pickup unit (direction detection means, second direction detection means)
50B imaging unit (direction detection means, second direction detection means)
52B Optical filter (filter for second illumination light source)
53 Image sensor L interval S1 Central circular area (selected area)
S2 Non-circular area (non-selected area)
λ1 first wavelength λ2 second wavelength

Claims (5)

Occurs when a light guide member, an illumination light source that is coupled to an edge of the light guide member and illuminates the inside of the light guide member, and a non-light emitting detection object and a light emission detection object come into contact with the light guide member And at least two direction detection means for detecting the traveling direction of the propagating light propagating through the inside of the light guide member, and based on the detection of the traveling direction of the propagating light by the direction detecting means, the triangulation method is used to detect the contact point. In a coordinate input device for obtaining position coordinates,
Illumination light source blinking means for periodically blinking the illumination light source;
Coordinate input is provided with detection means for detecting the position of the non-light emitting detection object during the lighting period of the illumination light source and detecting the position of the light emission detection object during the extinguishing period of the illumination light source. apparatus. The illumination light source comprises a first illumination light source and a second illumination light source, the direction detection means comprises a pair of first direction detection means and a pair of second direction detection means,
The first illumination light source and a pair of first direction detection means are provided at a first edge of the light guide member, and a second edge of the light guide member facing the first edge is provided at the second edge of the light guide member. The second illumination light source and a pair of second direction detection means are provided,
The first direction detection means is installed outside the irradiation range of the first illumination light source, and the second direction detection means is installed outside the irradiation range of the second illumination light source,
The first illumination light source and the second illumination light source emit light having different wavelengths,
The light emitting detection object emits light having the same wavelength as any one of the first illumination light source and the second illumination light source,
The first direction detection means is provided with a first illumination light source filter that selectively transmits light from the first illumination light source, and the second direction detection means selects light from the second illumination light source. A second illumination light source filter that is transparently transmitted,
The illumination light source blinking means alternately turns on the first illumination light source at the first edge and the second illumination light source at the second edge,
The detection means includes a pair of first direction detection means or second direction detection means on the side where the first illumination light source or the second illumination light source is lit during the lighting period of the first illumination light source or the second illumination light source. 2. The position detection of the light emitting detection object is performed using the pair of first direction detection means or the pair of second direction detection means while detecting the position of the non-light emission detection object. Coordinate input device. The light emitting detection object emits light having a first wavelength that emits light having the same first wavelength as light emitted from the illumination light source, and light having a second wavelength different from the light having the first wavelength. A second light-emitting target,
The at least two direction detection means are divided into a selection region that selectively transmits the light of the first wavelength and a non-selection region that transmits both the light of the first wavelength and the light of the second wavelength. The coordinate input device according to claim 1, further comprising a merge filter. A coordinate detection method using the coordinate input device according to any one of claims 1 to 3,
A coordinate detection method characterized in that the illumination light source is periodically blinked, the position of the non-light emitting target is detected during the lighting period of the illumination light source, and the position of the light emitting target is detected during the extinguishing period of the illumination light source. . A coordinate input system comprising the coordinate input device according to any one of claims 1 to 3,
A coordinate input system comprising an image display module.