JP2011081740A - Optical touch panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical touch panel that detects simultaneous inputs in a plurality of different positions in an input region of an optical touch panel without increasing the number of optical detection mechanisms. <P>SOLUTION: An optical touch panel 10 includes: an input region 12 having a rectangular contour in plan view; a light emitting part 14 installed along a part 12a of an outer edge of the input region; a light receiving part 16 installed along the other part 12b of the outer edge of the input region so as to be in parallel with and to face the light emitting part; and an operation processing part 18 which determines an input position of a finger or a pen in the input region on the basis of an output signal of the light receiving part. The light receiving part includes a plurality of light receiving members 20 which individually receive light L emitted from the light emitting part at a predetermined viewing angle α, and respectively output signals S corresponding to intensities of received rays of light, which are arranged in a line in an X-axis direction. On the basis of signals output from the plurality of light receiving members arranged in a line in the X-axis direction, the operation processing part calculates coordinates x and y on the X and Y axes, respectively, of the input position in the input region. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical touch panel.

  The touch panel is an electronic device equipped with a display device such as a personal computer, an automatic teller machine (ATM), a vending machine, a copying machine, a car navigation system, a mobile phone, a personal digital assistant (PDA), a game machine, etc. (Liquid Crystal Display), PDP (Plasma Panel), CRT (Brown Tube), etc. are known as panel type input devices that are installed on the screen of a display device. The operator touches a desired position in the input area of the touch panel arranged on the screen of the display device with a finger or a pen to input and input the two-dimensional coordinates of the display image in the screen at the touch position. By inputting an instruction for an image display operation corresponding to the operation of the pen or the pen, it is possible to cause the electronic device to execute a corresponding process.

  An optical touch panel that uses a light-shielding detection method that detects when a finger or pen blocks radiation light, such as infrared rays, as a method for detecting input with a finger or pen, compared to other touch panels that use a resistive film method, etc. Therefore, the light transmittance and durability of the input region are generally excellent. A conventional optical touch panel includes a light emitting unit and a light receiving unit that are arranged along two opposite sides of the outer edge of the rectangular input area. In the light emitting section, a plurality of light emitting elements (for example, LEDs (light emitting diodes)) are arranged in a line at predetermined intervals. The light receiving unit receives light emitted from the light emitting elements at positions individually facing the plurality of light emitting elements, and outputs a plurality of light receiving elements (for example, photo) corresponding to the intensity of the received light, respectively. Diodes and phototransistors) are arranged in a line at predetermined intervals. And the light detection mechanism which has such a light emission part and a light-receiving part is each installed in two sets of opposing two sides of the outer edge of a rectangular input area (namely, the position which differs 90 degrees of central angles). The arithmetic processing unit of the optical touch panel scans a plurality of pairs of light-emitting elements and light-receiving elements at opposite positions for each of the two light detection mechanisms arranged orthogonally, and outputs an output signal of each light-receiving element. Based on this, a light receiving element that is determined to be blocked by the finger or the like from the light emitting element at the opposite position is identified, and thereby the coordinates of the indicated position of the finger or the like in the input area (using two light detection mechanisms) As a result, two-dimensional coordinates) are obtained.

  As an example of a conventional optical touch panel, Patent Document 1 describes a coordinate input / detection device that can improve the resolution of detection of a coordinate input position. This coordinate input / detection device “assigns a plurality of light receiving elements that belong to each light emitting element within the light emitting range and detect light emitted by the light emitting elements so as to be responsible for each of the light emitting elements. In addition, by sequentially emitting light from each light emitting element individually, a plurality of detection light paths having different radial directions that are finer than the respective arrangement intervals can be set when viewed from each light emitting element side and each light receiving element side. The two-dimensional coordinate input / detection region can be entirely covered by detection light paths in all directions, so that coordinates specified based on the positional relationship between a light emitting element and a light receiving element whose optical path is blocked are input two-dimensional coordinates. The position can be calculated with high resolution. "

  As another example of a conventional optical touch panel, Patent Document 2 describes a touch panel that can simultaneously input a plurality of points. This touch panel uses a parallel sensing line extending in three or more directions, or a radial sensing line centered on three or more points, at one end of each sensing line, Place the transmitting module, place the receiving module at the other end, for example, find the intersection of at least the sensing lines corresponding to the two receiving modules, and determine the distance between the sensing line corresponding to the other receiving module and the intersection In other words, a point where the distance is equal to or smaller than a predetermined threshold value is set as a touch point. "

JP 2002-091683 A (summary) JP-A-8-147091 (summary)

  A conventional optical touch panel (see, for example, Patent Document 1) using two light detection mechanisms (light emitting unit and light receiving unit) arranged orthogonally is used when a plurality of different positions are input simultaneously in an input area. In general, the coordinates of individual input positions cannot be specified. That is, in the orthogonal biaxial coordinate system, when the first position (x1, y1) and the second position (x2, y2) are input simultaneously, the first position (x1, y1) and the third position that is not input. Identifying the position (x1, y2) or the fourth position (x2, y1), the second position (x2, y2), the third position (x1, y2) or the fourth position (x2, y1) Is usually difficult to identify.

  On the other hand, a conventional optical touch panel (see, for example, Patent Document 2) using three light detection mechanisms (light emitting unit and light receiving unit) arranged to intersect in three directions simultaneously at a plurality of different positions in the input area. When input is performed, the coordinates of the individual input positions can be specified. However, there are concerns about an increase in device dimensions and an increase in manufacturing cost due to an increase in the number of light detection mechanisms.

  The present invention provides an optical touch panel that can detect simultaneous input at a plurality of different positions in an input area without increasing the number of light detection mechanisms.

  In one aspect, the input region having a two-dimensional extension, the light emitting unit installed along a part of the outer edge of the input region, and the light emitting unit installed parallel to and opposed to the light emitting unit along the other part of the outer edge of the input region. A light receiving unit, and an arithmetic touch panel that obtains an input position in an input area based on an output signal of the light receiving unit, the light receiving unit individually transmits light emitted from the light emitting unit at a predetermined viewing angle. A plurality of light receiving members, each of which outputs a signal corresponding to the intensity of the received light, arranged in parallel in the direction of the first axis; Based on signals output from each of a plurality of light receiving members juxtaposed in the direction of one axis, both the coordinates of the first axis and the coordinates of the second axis orthogonal to the first axis in the input area An optical touch characterized by Panel is provided.

  In another aspect, the input region having a two-dimensional extension, the light emitting unit installed along a part of the outer edge of the input region, and the light emitting unit installed parallel to and opposed to the light emitting unit along the other part of the outer edge of the input region In the optical touch panel comprising: a light receiving unit that is connected to the light receiving unit; and an arithmetic processing unit that obtains an input position in the input region based on an output signal of the light receiving unit. A plurality of light receiving elements arranged, each of which receives light emitted from the light emitting unit individually and outputs a signal corresponding to the intensity of the received light, and among the plurality of light receiving elements A plurality of optical components that are individually provided in a plurality of element arrays each including three or more light receiving elements, and that each of the plurality of element arrays receives the light emitted by the light emitting unit as parallel light; The arithmetic processing unit Among the three or more light receiving elements included in each of the plurality of element rows, a plurality of elements of a signal output by one central light receiving element closest to the optical axis of each of the plurality of optical components provided correspondingly Based on the size in each of the columns, the coordinates of the first axis of the input position in the input region are calculated, and among the three or more light receiving elements included in each of the plurality of element rows, the central light receiving element is directed in one direction. The magnitude of the signal output from the M-th (M is an integer of 1 or more) one-side light-receiving element in each of the plurality of element rows and the N-th in the opposite direction from the central light-receiving element (N is an integer of 1 or more) Calculating coordinates of a second axis orthogonal to the first axis of the input position in the input region based on the magnitude of each of the plurality of element rows of the signal output from the other light receiving element. An optical touch panel is provided.

  According to the optical touch panel according to one aspect, the first input position in the input area is detected using the light detection data of one light detection mechanism including the light emitting part and the light receiving part facing each other across the input area. Both axis coordinates and second axis coordinates can be determined. At this time, the input position and other non-input positions having the same first axis coordinate are clearly identified based on the change state of the difference in the magnitude of the output signal of the adjacent light receiving members. Therefore, simultaneous input at different positions in the input area can be detected without increasing the number of light detection mechanisms.

  According to the optical touch panel according to another aspect, the first position of the input position in the input region is detected using the light detection data of one light detection mechanism including the light emitting unit and the light receiving unit facing each other across the input region. Both the 1-axis coordinate and the second-axis coordinate can be obtained. At this time, by adopting the triangulation method, the second axis coordinates can be obtained with relatively high accuracy. Therefore, simultaneous input at different positions in the input area can be detected without increasing the number of light detection mechanisms.

It is a top view which shows the structure of an optical touch panel typically. It is a figure explaining the coordinate detection method of the optical touch panel of FIG. It is a figure explaining the coordinate detection method of the optical touch panel of FIG. It is a figure which shows the structure of an optical touch panel typically. It is a top view which shows typically the composition of the optical touch panel by one embodiment, and shows (a) an example of a photodetection mechanism, and (b) other examples of a photodetection mechanism, respectively. It is a top view which shows typically the structure of the optical touch panel by other embodiment. It is a figure explaining the coordinate detection method of the optical touch panel of FIG. It is a top view which shows typically the structure of another optical touch panel. It is a figure explaining the coordinate detection method of the optical touch panel of FIG. It is a figure explaining the coordinate detection method of the optical touch panel of FIG. It is a figure explaining the coordinate detection method of the optical touch panel of FIG.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Corresponding components are denoted by common reference symbols throughout the drawings.

  FIG. 1 is a plan view schematically showing a configuration of an optical touch panel 10 according to one embodiment of the present invention, and FIGS. 2 and 3 are diagrams illustrating a coordinate detection method of the optical touch panel 10. The optical touch panel 10 is installed on a screen of a display device (not shown) included in an electronic device (not shown), and enables an operator to input an image on the screen with a finger or a pen. is there.

  The optical touch panel 10 is installed along an input area 12 having a two-dimensional extension (in the figure, a rectangular outline in plan view) and a part of the outer edge of the input area 12 (one of two opposite sides of the rectangular outline in the figure) 12a. The light emitting unit 14, the other part of the outer edge of the input region 12 (the other of the opposing two sides of the rectangular contour in the drawing) 12 b, the light receiving unit 16 installed parallel to and opposed to the light emitting unit 14, and the light receiving unit And an arithmetic processing unit 18 for obtaining an input position (that is, a two-dimensional coordinate) of a finger or a pen in the input region 12 based on the 16 output signals. The light emitting unit 14 has a light emission function of radiating light (for example, infrared rays) L having a predetermined intensity toward the input region 12 within a range that covers substantially the entire length of the outer edge portion 12 a of the input region 12. The light receiving unit 16 receives a plurality of light L emitted from the light emitting unit 14 toward the input region 12 at a predetermined viewing angle α (> 0) in a range that covers substantially the entire length of the outer edge portion 12b of the input region 12. The light receiving members 20 are arranged side by side in the direction of the first axis (X axis in the figure) in the orthogonal biaxial coordinate system. Each of the light receiving members 20 has a photoelectric conversion function of outputting an electric signal (for example, a current value) corresponding to the intensity of received light.

  The arithmetic processing unit 18 is orthogonal to the X-axis coordinate (x) of the input position P in the input region 12 and the X-axis based on signals output from the plurality of light receiving elements 20 juxtaposed in the X-axis direction. Both the coordinate (y) of the second axis (Y axis in the figure) to be calculated are calculated. Hereinafter, a calculation method (coordinate detection method) of the input position P by the arithmetic processing unit 18 will be described with reference to FIGS. 2 and 3.

  When the optical touch panel 10 is in use, the light emitting unit 14 continuously emits light L having a predetermined intensity uniformly over the entire area toward the input region 12, and the light receiving unit 16 receives all light. The member 20 is configured to receive the light L emitted from the light emitting unit 14 and continuously output a uniform electric signal corresponding to the intensity of the light individually. When the operator performs an input operation on a desired position of the input area 12 with a finger or the like in this use state, the light emitted from the light emitting unit 14 to the input area 12 is locally applied by the finger or the like before reaching the light receiving unit 16. The intensity of light received by any one of the plurality of light receiving members 20 of the light receiving unit 16 is weakened, and the output signal of the light receiving member 20 is reduced.

  Here, in the optical touch panel 10, each light receiving member 20 has a predetermined viewing angle α, so that the Y with respect to the input position P according to the input position P (and therefore according to the amount of light to be blocked). One or more substantially aligned in the axial direction (the position of the input position P in the X-axis direction, the size of a light blocking object such as a fingertip or a pen tip, and the width dimension of light that can be received by one light receiving member 20 The output signal of the light receiving member 20 and the output signals of some light receiving members 20 in the vicinity of the output signal of the light receiving member 20 are significantly lower than the normal output signal where no input operation is performed. Show. For example, in the input state shown as one typical example in FIG. 2, as a result of the input operation being performed at the position P1 closer to the light emitting unit 14 than the light receiving unit 16, the input position P1 is substantially aligned in the Y-axis direction. The output signal S of one light-receiving member 20a and the output signals S of the two light-receiving members 20b on the left and right sides of the light-receiving member 20a are the other light-receiving members 20 by a magnitude corresponding to the amount of light to be blocked. Is lower than the output signal S (graph G1). Further, in the input state shown in FIG. 3 as another typical example, as a result of the input operation being performed at the position P2 closer to the light receiving unit 16 than the light emitting unit 14, the input position P2 is substantially aligned in the Y-axis direction. The output signals S of the two light receiving members 20c and the output signals S of the left and right light receiving members 20d of the light receiving members 20c are different from each other by a magnitude corresponding to the amount of light to be blocked. It is lower than the output signal S of the light receiving member 20 (graph G1).

  The arithmetic processing unit 18 uses the magnitudes (absolute values) of the individual output signals S in all the light receiving members 20 of the light receiving unit 16 as independent variables, and follows the predetermined function according to the X-axis coordinates (x) of the input position P. Can be calculated. In the typical example of FIG. 2, the geometric center point on the X axis of the light receiving member 20a itself is the X axis coordinate (x1) of the input position P1. In the typical example of FIG. 3, the geometric center point on the X axis between the two light receiving members 20c is the X axis coordinate (x2) of the input position P2. Note that the function for calculating the X-axis coordinate (x) of the input position P can be appropriately set by an experiment at the time of designing the optical touch panel 10 or the like.

  Further, the arithmetic processing unit 18 selects the magnitude of the signal S output from any one (first) light receiving member 20 among all the light receiving members 20 of the light receiving unit 16 and any one adjacent to the first light receiving member 20. Using the difference D (relative value) from the magnitude of the signal S output from one (second) light receiving member 20 as an independent variable, the coordinate (y) of the Y axis of the input position P is determined according to a predetermined function. Can be calculated. In the typical example of FIG. 2, the difference D in the magnitude of the output signal S between the first light receiving member 20 and the second light receiving member 20 adjacent to the right in the figure is the light reception in which the output signal S has the lowest value. In the periphery of the member 20a, it changes gently over a relatively wide range (graph G2). This means that the shadow of the finger or the like at the input position P1 detected by the light receiving unit 16 is blurred. As a result, it can be determined that the input position P1 is relatively far from the light receiving unit 16. On the other hand, in the typical example of FIG. 3, the difference D in the magnitude of the output signal S between the first light receiving member 20 and the second light receiving member 20 adjacent to the right in the figure is the minimum value of the output signal S. In the vicinity of the light receiving member 20c shown, it changes abruptly over a relatively narrow range (graph G2). This means that the shadow of the input position P2 detected by the light receiving unit 16 is clear, and as a result, it can be determined that the input position P2 is relatively close to the light receiving unit 16. By predetermining such a determination algorithm as a function, the coordinates (y1) and (y2) of the Y axis of the input positions P1 and P2 can be calculated. Note that the function for calculating the Y-axis coordinate (y) of the input position P can be appropriately set by an experiment at the time of designing the optical touch panel 10 or the like.

  As described above, the optical touch panel 10 uses the light detection data S and D of one light detection mechanism provided with the light emitting unit 14 and the light receiving unit 16 facing each other with the input region 12 interposed therebetween, and the input region. 12, both the X-axis coordinate (x) and the Y-axis coordinate (y) of the input position P can be obtained. For example, in the typical example of FIG. 2, the coordinates (x1, y1) of the input position P1 are obtained according to a predetermined function based on the output signals S of all the light receiving members 20 of the light receiving unit 16. At this time, the input position P1 and another non-input position P1 ′ having the same X-axis coordinate are clearly identified based on the change state of the difference D in the magnitude of the output signal S of the adjacent light receiving member 20. The Similarly, in the typical example of FIG. 3, the coordinates (x2, y2) of the input position P2 are obtained according to a predetermined function based on the output signals S of all the light receiving members 20 of the light receiving unit 16. At this time, the input position P2 and another non-input position P2 ′ having the same X-axis coordinate are clearly identified based on the change state of the difference D in the magnitude of the output signal S of the adjacent light receiving member 20. The

  Therefore, in the optical touch panel 10, when the input operation is performed simultaneously on the first input position P1 (x1, y1) and the second input position P2 (x2, y2) in the input area 12, for example, the actual input position P1. (X1, y1) and the position P1 ′ (x1, y2) or P2 ′ (x2, y1) which are not input are clearly identified, and the actual input position P2 (x2, y2) and the same position P1 '(X1, y2) or P2' (x2, y1) is clearly identified, and the first input position P1 (x1, y1) and the second input position P2 (x2, y2) are reliably detected. The Even when there are three or more simultaneous input positions, the coordinates of the individual input positions can be obtained in the same manner using only the light detection data of one light detection mechanism (light emitting unit 14 and light receiving unit 16). Therefore, according to the optical touch panel 10, it is possible to detect simultaneous input at a plurality of different positions in the input region 12 without increasing the number of light detection mechanisms (light emitting units 14 and light receiving units 16). Become.

  In the above configuration for obtaining the coordinates (x, y) of the input position P from the light detection data S, D of one light detection mechanism (the light emitting unit 14 and the light receiving unit 16), the detection accuracy of the Y axis coordinate is the X axis coordinate. It tends to be lower than the detection accuracy. Therefore, it can be said that the above configuration is useful for applications where the coordinate detection accuracy in the input area 12 may be low, or for applications where high coordinate detection accuracy is required only in one axis direction. When high coordinate detection accuracy is required for the entire orthogonal biaxial coordinate system, the light detection mechanism having the light emitting unit 14 and the light receiving unit 16 is connected to the outer edge of the rectangular input region 12 as shown in FIG. It is desirable to have a configuration in which they are respectively installed on two opposite sides of the set (that is, at positions different from the central angle 90 °).

  The optical touch panel 100 shown in FIG. 4 is the same as the first light detection mechanism 102 including the first light emitting unit 14 and the first light receiving unit 16 shown in FIG. And a second light detection mechanism 104 including a second light emitting unit 14-2 and a second light receiving unit 16-2 having a configuration. The second light emitting unit 14-2 is formed on a portion 12c (one of the second opposing two sides having a rectangular outline in the drawing) of the outer edge of the input region 12 and orthogonal to the portion 12a where the first light emitting unit 14 is installed. The second light receiving unit 16-2 is disposed along the other edge of the outer edge of the input region 12 and is orthogonal to the portion 12b where the first light receiving unit 16 is installed (in FIG. It is installed along the other side 12d in parallel and opposite to the second light emitting unit 14-2. As a result, the first light emitting unit 14 and the first light receiving unit 16 of the first light detection mechanism 102, and the second light emitting unit 14-2 and the second light receiving unit 16- of the second light detection mechanism 104 are obtained. 2 is installed at a position shifted from each other by 90 degrees along the outer edge of the input area 12.

  The second light emitting unit 14-2 has a light emission function of emitting light having a predetermined intensity (for example, infrared rays) toward the input region 12 in a range that extends over substantially the entire length of the outer edge portion 12 c of the input region 12. . The second light receiving unit 16-2 predetermines light (for example, infrared rays) radiated toward the input region 12 by the second light emitting unit 14-2 within a range that covers the substantially entire length of the outer edge portion 12d of the input region 12. A plurality of light receiving members 20-2 individually received at a viewing angle α (> 0) are arranged in parallel in the direction of the second axis (Y axis in the figure) in the orthogonal biaxial coordinate system. Each of the light receiving members 20-2 has a photoelectric conversion function of outputting an electric signal (for example, a current value) corresponding to the intensity of received light.

  In the optical touch panel 100 having the above configuration, the arithmetic processing unit 18 uses the light detection data (S, D) of the first light detection mechanism 102 by the above-described coordinate detection method to input position P in the input area 12. Both the X-axis coordinate (x) and the Y-axis coordinate (y), particularly the X-axis coordinate (x), can be obtained with high accuracy. In addition, the arithmetic processing unit 18 uses the light detection data (S, D) of the second light detection mechanism 104 in the same manner as the coordinate detection method described above, and uses the Y-axis coordinates of the input position P in the input region 12. Both (y) and the X-axis coordinate (x) can be obtained with high accuracy, particularly for the Y-axis coordinate (y). Therefore, according to the optical touch panel 100, the input position P is detected with high coordinate detection accuracy on both the X axis and the Y axis over the entire input region 12. Further, the optical touch panel 100 can detect simultaneous inputs at a plurality of different positions in the input area 12 without providing three or more light detection mechanisms (light emitting unit 14 and light receiving unit 16). it can.

  In the figure, the outline shape of the input area 12 is shown as a square, but the input area 12 can have various rectangular outline shapes with different X-axis direction dimensions and Y-axis direction dimensions. Further, the number and viewing angle of the light receiving members 20 in the first light detection mechanism 102 and the number and viewing angle of the light receiving members 20-2 in the second light detection mechanism 104 are the same or different from each other. Also good.

  In the optical touch panels 10 and 100, when the plurality of light receiving members 20 have a sensitivity difference with each other in a standard state, there is a concern that accurate coordinate detection becomes difficult. In addition, the light receiving members 20 located at both ends of the light receiving unit 16 and in the vicinity thereof receive less light from the light emitting unit 14 than other light receiving members 20 (in the case of the optical touch panel 10) or other light. It is predicted that the amount of received light will be large (in the case of the optical touch panel 100) due to the intrusion of radiated light from the light emitting unit 14 of the detection mechanism, and there is a concern that accurate coordinate detection will be difficult. Therefore, the arithmetic processing unit 18 can include a correction unit 22 that corrects an error of the output signal S caused by the sensitivity difference or arrangement of the plurality of light receiving members 20 (FIG. 4). In this configuration, the arithmetic processing unit 18 calculates the X-axis coordinate (x) and the Y-axis coordinate (y) of the input position P based on the output signal S corrected by the correction unit 22. According to such a configuration, the coordinate detection accuracy in the input area 12 can be further improved.

  As an example of the correction method by the correction unit 22, the output signals S of the plurality of light receiving members 20 are recorded in a state where no light shielding object such as a finger or a pen exists in the input area 12 with respect to the optical touch panels 10 and 100 in use. A correction coefficient for converting the output signal S of the light receiving members 20 into a common reference value (for example, 1) is obtained in advance for each light receiving member 20. When the input position is detected, the output signal S of each light receiving member 20 is multiplied by a correction coefficient obtained in advance, thereby correcting the error of the output signal S due to the sensitivity difference or arrangement of the light receiving members 20. .

  The optical touch panels 10 and 100 include display devices such as personal computers, automatic teller machines (ATMs), vending machines, copying machines, car navigation systems, mobile phones, personal digital assistants (PDAs), and game machines. In an electronic device (not shown), it can be installed in an appropriate arrangement on the screen of a display device (not shown) such as an LCD (liquid crystal display), a PDP (plasma panel), or a CRT (CRT). The input area 12 where the operator performs an input operation with a finger or a pen can be formed from a transparent glass plate, plastic plate, or the like that can be placed over the screen of the display device. Alternatively, instead of providing such an input area 12 made of a transparent plate, the screen of the display device itself may be used as the input area 12. The input operation by the operator is usually performed by bringing a fingertip or a pen tip into contact with the surface of the input region 12. For example, a light detection line extending from the light emitting unit 14 to the light receiving unit 16 is somewhat from the surface of the input region 12. By setting the positions apart from each other, an input operation can be performed without bringing a fingertip or a pen tip into contact with the surface of the input area 12.

  FIG. 5 schematically shows an embodiment of the optical touch panel 10 with the arithmetic processing unit 18 omitted. In this embodiment, the light-emitting unit 14 includes a plurality of light-emitting elements (for example, light-emitting diodes (LEDs)) that are arranged at a predetermined pitch t1 along the outer edge portion 12a of the input region 12 in the direction of the first axis (X-axis). 24 and a plurality of optical components (for example, lenses) that direct light L emitted from each light emitting element 24 toward the light receiving unit 16 at a predetermined radiation angle β (> 0). , Mirror, etc.) 26. The plurality of light emitting elements 24 emit light (for example, infrared rays) having a predetermined intensity toward the input region 12 at positions that are appropriately dispersed over substantially the entire length of the outer edge portion 12 a of the input region 12. The light receiving unit 16 includes a plurality of light receiving elements (for example, photodiodes and phototransistors) 28 arranged along the outer edge portion 12b of the input region 12 in the first axis (X axis) direction at a predetermined pitch t2. A plurality of optical components (for example, lenses, mirrors, etc.) 30 provided individually for each of the light receiving elements 28 so that each light receiving element 28 receives the light L emitted from the light emitting unit 14 at the aforementioned viewing angle α. And is configured. The plurality of light receiving elements 28 are individually dispersed at a viewing angle α with the light L emitted from the plurality of light emitting elements 24 at a radiation angle β at positions appropriately dispersed over substantially the entire length of the outer edge portion 12b of the input region 12. An electric signal (for example, a current value) corresponding to the intensity of the received light is output individually. In this embodiment, one light receiving element 28 and one optical component 30 provided corresponding to the light receiving element 28 constitute each of the plurality of light receiving members 20 shown in FIG.

  In the above embodiment, the arithmetic processing unit 18 (FIG. 1) uses the magnitudes (absolute values) of the individual output signals S (FIGS. 2 and 3) in all the light receiving elements 28 of the light receiving unit 16 as independent variables in advance. According to the determined function, the coordinate (x) of the first axis (X axis) of the input position P can be calculated. The arithmetic processing unit 18 (FIG. 1) also determines the magnitude of the signal S output from any one (first) light receiving element 28 among all the light receiving elements 28 of the light receiving unit 16 and the first light receiving element 28. The input position P is determined in accordance with a predetermined function, with the difference D (relative value) (FIGS. 2 and 3) from the magnitude of the signal S output from one (second) light receiving element 28 adjacent to each other as an independent variable. The coordinate (y) of the second axis (Y-axis) can be calculated. According to such a configuration, in addition to the effects that are equivalent to the effects described above of the optical touch panel 10, for example, when repairing the light emitting unit 14 or the light receiving unit 16, a part of the light emitting unit 14 is provided. Since only the light emitting element 24 can be replaced, or only a part of the light receiving elements 28 of the light receiving unit 16 can be replaced, an advantage that the maintenance cost can be suppressed is obtained.

  In the above embodiment, for example, as shown as one typical example in FIG. 5A, each of the plurality of light emitting elements 24 and each of the plurality of light receiving elements 28 are arranged at positions facing each other in the Y-axis direction. Can be configured. Alternatively, as shown in FIG. 5B as another typical example, each of the plurality of light emitting elements 24 and each of the plurality of light receiving elements 28 are in positions where they do not face each other in the Y-axis direction. It can be set as the structure arrange | positioned in the position mutually shifted | deviated by 1/2 pitch to the direction of the axis | shaft. In the illustrated example, the arrangement pitch t1 of the light emitting elements 24 and the arrangement pitch t2 of the light receiving elements 28 are the same, but the pitches t1 and t2 may be different from each other. Further, the emission angle β of each light emitting element 24 defined by the optical component 26 and the viewing angle α of each light receiving element 28 defined by the optical component 30 may be the same or different from each other.

  The emission angle β of each light emitting element 24 determined by the optical component 26 is an angle range in which the light L is irradiated to, for example, two (FIG. 5B) or more and seven (FIG. 5A) or less light receiving elements 28. You can choose from. Similarly, the viewing angle α of each light receiving element 28 determined by the optical component 30 is, for example, two or more (FIG. 5B) and seven (FIG. 5A) light L from the light emitting elements 24. You can select from the range of angles to receive. The emission angle β is an angle at which the light L is applied to the light receiving elements 28 of less than two or more than seven, or the light emitting elements 24 of which the viewing angle α is less than two or more than seven. 24, the difference D (FIGS. 2 and 3) in the magnitude of the output signal S of the adjacent light receiving elements 28 changes so much even if the Y-axis coordinate of the input position P changes. The detection accuracy for the Y-axis coordinates and the detection accuracy for multi-point simultaneous input tend not to meet the requirements for a general touch panel.

  As shown in FIG. 5A, the optical component 26 provided in each light emitting element 24 is provided in advance in a transparent package (for example, an LED lamp package) itself that houses an element chip that is a constituent element of the light emitting element 24. The lens-shaped portion may have the function of the optical component 26, or an optical component 26 separate from the light emitting element 24 may be used as shown in FIG. Good. Similarly, with respect to the optical component 30 provided in each light receiving element 28, as shown in FIG. 5A, a transparent package (for example, a photodiode package) itself that accommodates an element chip as a component of the light receiving element 28 is provided. The lens-shaped portion provided in advance may have the function of the optical component 30, or an optical component 30 separate from the light receiving element 28 may be used as shown in FIG. It may be. The configuration in which the lens-shaped portion of the package included in the light emitting element 24 or the light receiving element 28 itself is used as the optical components 26 and 30 has an advantage that the number of components of the touch panel 10 can be reduced. On the other hand, in a configuration using optical components 26 and 30 that are separate from the light emitting element 24 or the light receiving element 28, the emission angle β of the light emitting element 24 or the viewing angle α of the light receiving element 28 can be simply replaced. There is an advantage that can be adjusted as necessary.

  In the embodiment described above, a configuration having a light guide member extending in the X-axis direction can be adopted as the light-emitting unit 14 instead of the configuration having the plurality of light-emitting elements 24 arranged in a predetermined pitch in the X-axis direction. . In addition, instead of a configuration having a plurality of light receiving elements 28 arranged side by side at a predetermined pitch in the X-axis direction as the light receiving unit 16, a plurality of light receiving elements (elements) arranged linearly connected to each other in the X-axis direction. A configuration having a chip) (so-called line sensor) can be employed. FIG. 6 schematically shows another embodiment of the optical touch panel 10 that employs such an alternative configuration for both the light emitting unit 14 and the light receiving unit 16, omitting the arithmetic processing unit 18. FIG. 7 is a diagram for explaining a coordinate detection method of the optical touch panel 10 according to the embodiment of FIG.

  As shown in FIGS. 6 and 7, in this embodiment, the light emitting unit 14 includes a light guide member 32 extending in the direction of the first axis (X axis) along the outer edge portion 12 a of the input region 12. Configured. The light guide member 32 propagates light emitted from the light source 34 in the longitudinal direction, and inputs light (for example, infrared rays) L having a predetermined intensity in a range that extends over substantially the entire length of the outer edge portion 12 a of the input region 12. Radiates toward region 12. As the light guide member 32, a light guide plate formed into a desired shape from a resin material such as acrylic can be used. In addition, the light receiving unit 16 includes a plurality of light receiving elements (for example, element chips such as photodiodes) arranged linearly connected to each other in the direction of the first axis (X axis) along the outer edge portion 12b of the input region 12. 36 and each of the plurality of element arrays 38 each including one or more of the light receiving elements 36, and each element array 38 receives the light L emitted from the light emitting unit 14. And a plurality of optical components (for example, lenses, mirrors, etc.) 40 to be received at the viewing angle α. The plurality of light receiving elements 36 are linearly connected to the surface of the base material 42 and are prepared as so-called line sensors. The plurality of light receiving elements 36 included in the plurality of element arrays 38 transmit the light L radiated from the light guide member 32 at a viewing angle α at a position appropriately distributed over substantially the entire length of the outer edge portion 12b of the input region 12. Each light receiving element 36 individually outputs an electric signal (for example, a current value) corresponding to the intensity of the received light. In this embodiment, one element row 38 and one optical component 40 provided corresponding to the element row 38 constitute each of the plurality of light receiving members 20 shown in FIG.

  In the above embodiment, the arithmetic processing unit 18 (FIG. 1) uses the magnitudes (absolute values) of the individual output signals S (FIGS. 2 and 3) in all the light receiving elements 36 of the light receiving unit 16 as independent variables in advance. According to the determined function, the coordinate (x) of the first axis (X axis) of the input position P can be calculated. The arithmetic processing unit 18 (FIG. 1) outputs a signal output by any one specific light receiving element 36a included in any one (first) element array 38 among all the element arrays 38 of the light receiving unit 16. The first S included in one (second) element row 38 corresponding to another optical component 40 adjacent to the magnitude of S and the optical component 40 provided corresponding to the first element row 38. The difference D (relative value) (FIGS. 2 and 3) from the magnitude of the signal S output from any one specific light receiving element 36a at the same relative position as the specific light receiving element 36a in the element row 38 is an independent variable. The coordinates (y) of the second axis (Y axis) of the input position P can be calculated according to a predetermined function. For example, one light receiving element 36 closest to the optical axis 40a of each optical component 40 (adjacent to the left side in the figure) is set as the specific light receiving element 36a, and the difference D can be obtained using the light detection data.

  Alternatively, the arithmetic processing unit 18 (FIG. 1) includes any two or more specific light receiving elements 36 a included in any one (first) element row 38 among all the element rows 38 of the light receiving unit 16. The sum of the magnitudes of the signals S to be output and one (second) element row 38 corresponding to another optical component 40 adjacent to the optical component 40 provided corresponding to the first element row 38. The difference D from the total sum of the magnitudes of the signals S output from any two or more specific light receiving elements 36a at the same relative position as the specific light receiving elements 36a of the first element array 38 is included as an independent variable. The Y-axis coordinate (y) of the input position P can also be calculated according to a predetermined function. In any of the coordinate detection methods, according to the above configuration, in addition to the exceptional effect equivalent to the above-described effect of the optical touch panel 10, the resolution of the line sensor is essentially included. Coordinate detection accuracy can be improved by the height.

  In the above embodiment, the viewing angle α of each element array 38 determined by the optical component 40 can be selected from an angle range according to the embodiment of FIG. Further, the operator determines in advance which light receiving element 36 in the element array 38 is the specific light receiving element 36a to which the light detection data is referred when the arithmetic processing unit 18 calculates the coordinates (x, y) of the input position P. It can be set in the arithmetic processing unit 18.

  5 and 6, in the same manner as the optical touch panel 100 in FIG. 4, the light detection mechanisms (the light emitting unit 14 and the light receiving unit 16) having the same structure are arranged on the outer edge of the rectangular input region 12. It can also be set as the structure each installed in two sets of two opposite sides (that is, in the position which differs 90 degrees of central angles). With this configuration, high coordinate detection accuracy can be realized in the entire orthogonal biaxial coordinate system. 5 and FIG. 6, the arithmetic processing unit 18 corrects the error of the output signal S caused by the sensitivity difference or arrangement of the plurality of light receiving elements 28 and 36 (FIG. 4). ). With this configuration, the coordinate detection accuracy in the input area 12 can be further improved.

  FIG. 8 schematically shows a configuration of an optical touch panel 200 according to another aspect of the present invention. 9-11 is a figure explaining the coordinate detection method of the optical touch panel 200 of FIG. The optical touch panel 200 has the same configuration as the optical touch panel 10 according to the embodiment of FIG. 6 except that the configuration of the optical components of the light receiving unit 16 and the coordinate detection method by the arithmetic processing unit 18 are different. Are denoted by common reference numerals, and detailed description thereof is omitted.

  The optical touch panel 200 includes an input region 12 having a two-dimensional extension, a light emitting unit 14 installed along a part 12 a of the outer edge of the input region 12, and a light emitting unit along the other part 12 b of the outer edge of the input region 12. 14 and the input position (that is, two-dimensional coordinates) of the finger or pen in the input region 12 based on the light receiving unit 16 installed in parallel with and opposite to 14 and the output signal S (FIGS. 2 and 3) of the light receiving unit 16. And an arithmetic processing unit 18 to be obtained. The light emitting unit 14 includes a light guide member 32 that extends in the direction of the first axis (X axis) along the outer edge portion 12 a of the input region 12. The light guide member 32 propagates light emitted from the light source 34 in the longitudinal direction, and inputs light (for example, infrared rays) L having a predetermined intensity in a range that extends over substantially the entire length of the outer edge portion 12 a of the input region 12. Radiates toward region 12. The light receiving unit 16 includes a plurality of light receiving elements 36 that are linearly connected to each other in the direction of the first axis (X axis) along the outer edge portion 12 b of the input region 12, and of the light receiving elements 36. A plurality of element arrays 38 each including three or more light receiving elements 36 are individually provided, and each element array 38 converts the light L emitted from the light emitting unit 14 into parallel light (that is, a viewing angle α = 0). And a plurality of optical components (for example, lenses, mirrors, etc.) 202 to be received. The plurality of light receiving elements 36 are linearly connected to the surface of the base material 42 and are prepared as so-called line sensors. The plurality of light receiving elements 36 included in the plurality of element rows 38 are formed by using the light L emitted from the light guide member 32 as parallel light at positions that are appropriately dispersed over substantially the entire length of the outer edge portion 12b of the input region 12. Each light receiving element 36 individually receives an electric signal (for example, a current value) corresponding to the intensity of the received light.

  In the optical touch panel 200, the arithmetic processing unit 18 includes an optical axis 202 a of each optical component 202 provided correspondingly among the three or more light receiving elements 36 included in each of all the element rows 38 of the light receiving unit 16. Based on the magnitude (absolute value) in each element array 38 of the signal S (FIGS. 2 and 3) output by one central light receiving element 36b (FIG. 9) closest to (adjacent to the left side in the figure) The coordinates of the first axis (X axis) of the input position P in the input area 12 are calculated. In this embodiment, each light receiving element 36 receives the light L radiated from the light guide member 32 as parallel light, and therefore one or more (input positions P) substantially aligned in the Y-axis direction with respect to the input position P. The number of light receiving elements in the X-axis direction and the size of the light-shielding object such as a fingertip or a pen tip and the width dimension of light that can be received by one element array 38). The output signal S of 36b becomes lower than the output signal S of the central light receiving element 36b of the other element array 38 by a magnitude corresponding to the amount of light to be blocked. Therefore, the arithmetic processing unit 18 uses the magnitude (absolute value) of the output signal S of the central light receiving element 36b in all the element arrays 38 as an independent variable, and follows the predetermined function according to the X-axis coordinate (x) of the input position P. Can be calculated. Note that the function for calculating the X-axis coordinate (x) of the input position P can be appropriately set by an experiment at the time of designing the optical touch panel 10 or the like.

  The arithmetic processing unit 18 also includes an Mth element (M is an integer of 1 or more) from the central light receiving element 36b in one direction among the three or more light receiving elements 36 included in each of all the element arrays 38 of the light receiving unit 16. : Left side M = 2 in the figure) The magnitude (absolute value) of the signal S output from the one side light receiving element 36c (FIG. 10) in each element row 38 and the Nth ( N is an integer greater than or equal to 1 (right side N = 4 in the figure), based on the magnitude (absolute value) of the signal S output from the other light receiving element 36d (FIG. 11) in each element array 38. The coordinates of the second axis (Y axis) orthogonal to the X axis of the input position P at are calculated. As described above, in this embodiment, each light receiving element 36 receives the light L emitted from the light guide member 32 as parallel light, so that the direction R1 obliquely intersects the input position P at a predetermined angle with respect to the Y axis. , One or a plurality of element rows 38 that are substantially aligned with R2 (the number is determined by the relationship between the size of a light blocking object such as a fingertip or a pen tip and the width direction dimension of light that can be received by one element row 38). Similarly to the central light receiving element 36b, the output signal S of the one side light receiving element 36c and the other side light receiving element 36d has a magnitude corresponding to the amount of light to be blocked, and the one side light receiving element 36c of the other element row 38. And lower than the output signal S of the other-side light receiving element 36d.

  Therefore, the arithmetic processing unit 18 firstly selects the one-side light receiving element 36c and the other light-receiving elements 36c and the other light-receiving elements 36d in all the element arrays 38, whose output signal S has the smallest magnitude (absolute value). The respective X-axis coordinates (xq1) and (xq2) of the side light receiving element 36d are calculated as the points of interest Q1 and Q2. Further, the arithmetic processing unit 18 determines the inclination angles (within the element array 38) that the respective X-axis coordinates (xq1) and (xq2) of the calculated points of interest Q1 and Q2 and the directions R1 and R2 form with respect to the Y-axis. The Y-axis coordinate (y) of the input position P can be calculated by a triangulation method based on the relative position of the one side light receiving element 36c and the other side light receiving element 36d.

  Unlike the optical touch panel 10 described above, the optical touch panel 200 uses light detection data of each light receiving element 36 of a line sensor that receives parallel light, and calculates the Y-axis coordinate (y) of the input position P. Since the triangulation method is employed, the light detection data S of one light detection mechanism including the light emitting unit 14 and the light receiving unit 16 facing each other across the input region 12 is used. Both the X-axis coordinate (x) and the Y-axis coordinate (y) of the input position P can be obtained with relatively high accuracy. Further, by adopting the triangulation method, it is possible to detect simultaneous inputs at a plurality of different positions in the input area 12 as in the optical touch panel 10.

  In the above-described embodiment, the central light receiving element 36b, the one side light receiving element 36c, and the other side light receiving element 36d, to which the arithmetic processing unit 18 refers to the photodetection data when calculating the coordinates (x, y) of the input position P, are arranged in the element array Which light receiving element 36 in 38 can be set in the arithmetic processing unit 18 in advance by the operator. Further, in the above embodiment, similar to the optical touch panel 100 of FIG. 4, the light detection mechanisms (the light emitting unit 14 and the light receiving unit 16) having the same structure are arranged in two sets of opposing two sides on the outer edge of the rectangular input region 12. (That is, at a position different from the central angle of 90 °). With this configuration, high coordinate detection accuracy can be realized in the entire orthogonal biaxial coordinate system. In the above-described embodiment, the arithmetic processing unit 18 may include the correction unit 22 (FIG. 4) that corrects the error of the output signal S caused by the sensitivity difference or arrangement of the plurality of light receiving elements 28 and 36. it can. With this configuration, the coordinate detection accuracy in the input area 12 can be further improved.

10, 100, 200 Optical touch panel 12 Input area 14 Light emitting unit 16 Light receiving unit 18 Arithmetic processing unit 20 Light receiving member 22 Correction unit 24 Light emitting element 26, 30, 40, 202 Optical component 28, 36 Light receiving element 32 Light guide member 34 Light source 36a Specific light receiving element 36b Central light receiving element 36c One side light receiving element 36d Other side light receiving element 38 Element array 40a Optical axis

Claims (11)

An input region having a two-dimensional extension, a light emitting unit installed along a part of the outer edge of the input region, and a light emitting unit installed parallel to and opposite to the light emitting unit along the other part of the outer edge of the input region An optical touch panel comprising: a light receiving unit that includes: an arithmetic processing unit that obtains an input position in the input region based on an output signal of the light receiving unit;
The light receiving unit is a plurality of light receiving members that individually receive the light emitted from the light emitting unit at a predetermined viewing angle, and each of the light receiving members outputs a signal corresponding to the intensity of the received light, It is provided in a form juxtaposed in the direction of the first axis,
The arithmetic processing unit, based on the signal output from each of the plurality of light receiving members juxtaposed in the direction of the first axis, the coordinates of the first axis of the input position in the input region, and the first Calculating both the coordinates of the second axis perpendicular to the axis;
An optical touch panel characterized by   The light receiving section is provided separately for each of the plurality of light receiving elements arranged in a predetermined pitch in the direction of the first axis, and one for each of the plurality of light receiving elements, and each of the plurality of light receiving elements has the viewing angle. A plurality of optical components configured to receive the light, and each of the plurality of light receiving members includes one light receiving element and one optical component provided corresponding to the light receiving element. The optical touch panel according to claim 1 configured.   The arithmetic processing unit includes: a magnitude of the signal output by the first light receiving element among the plurality of light receiving elements; and a magnitude of the signal output by the second light receiving element adjacent to the first light receiving element. The optical touch panel according to claim 2, wherein coordinates of the second axis of the input position are calculated based on the difference.   The light receiving unit includes a plurality of light receiving elements arranged linearly connected to each other in the direction of the first axis, and a plurality of element rows each including one or more light receiving elements among the plurality of light receiving elements. A plurality of optical components that are individually provided one by one, and each of the plurality of element arrays receives the light at the viewing angle, and each of the plurality of light receiving members includes one element array The optical touch panel according to claim 1, wherein the optical touch panel is configured to correspond to the element row.   The arithmetic processing unit is configured to output the magnitude of the signal output from any one specific light receiving element included in the first element array and the one corresponding to the first element array among the plurality of element arrays. Any one specific light receiving element in the same relative position as the specific light receiving element of the first element row included in the second element row corresponding to the other one optical component adjacent to the optical component is output. The optical touch panel according to claim 4, wherein coordinates of the second axis of the input position are calculated based on a difference between the magnitude of the signal to be performed.   The arithmetic processing unit includes a sum of magnitudes of the signals output from any two or more specific light receiving elements included in the first element array, and the first element array. Any two in the same relative position as the specific light receiving element of the first element row included in the second element row corresponding to the other one optical component adjacent to the corresponding one optical component The optical touch panel according to claim 4, wherein coordinates of the second axis of the input position are calculated based on a difference from a sum of magnitudes of the signals output by the specific light receiving elements.   The light emitting unit is provided separately for each of the plurality of light emitting elements arranged in a predetermined pitch in the direction of the first axis, and for each of the plurality of light emitting elements, and the light emitted by each of the light emitting elements is predetermined. The optical touch panel according to any one of claims 1 to 6, comprising a plurality of optical components directed toward the light receiving unit at a radiation angle of.   The light emitting unit is a light guide member extending in the direction of the first axis, and propagates light emitted from a light source to emit light over the entire portion of the outer edge of the input region. The optical touch panel according to claim 1, comprising: An input region having a two-dimensional extension, a light emitting unit installed along a part of the outer edge of the input region, and a light emitting unit installed parallel to and opposite to the light emitting unit along the other part of the outer edge of the input region An optical touch panel comprising: a light receiving unit that includes: an arithmetic processing unit that obtains an input position in the input region based on an output signal of the light receiving unit;
The light receiving unit is
A plurality of light receiving elements arranged linearly connected to each other in the direction of the first axis, each receiving light emitted by the light emitting unit, and each receiving a signal corresponding to the intensity of the received light A plurality of light receiving elements to output,
Each of the plurality of light receiving elements is individually provided in a plurality of light receiving elements each including three or more light receiving elements, and the light emitted from the light emitting unit receives each of the light emitting elements as parallel light. A plurality of optical components to be
The arithmetic processing unit
Of the three or more light receiving elements included in each of the plurality of element arrays, the signal output by one central light receiving element closest to the optical axis of each of the plurality of optical components provided correspondingly is provided. Calculating the coordinates of the first axis of the input position in the input region based on the size in each of the plurality of element rows,
Of the three or more light receiving elements included in each of the plurality of element rows, the M-side (M is an integer of 1 or more) one-side light receiving element outputs the signal from the central light receiving element in one direction. , Each of the plurality of element rows of the plurality of element rows and the signal output by the Nth (N is an integer of 1 or more) other side light receiving elements in the opposite direction from the central light receiving element. Calculating the coordinates of the second axis orthogonal to the first axis of the input position in the input region based on the size at
An optical touch panel characterized by   A first light detection mechanism including the light emitting unit and the light receiving unit, and a second light detection mechanism including a second light emitting unit and a second light receiving unit having the same configuration as the light emitting unit and the light receiving unit, respectively. The light emitting unit and the light receiving unit of the first light detection mechanism, and the second light emitting unit and the second light receiving unit of the second light detection mechanism are included in the input region. The optical touch panel according to claim 1, wherein the optical touch panel is installed at a position shifted by 90 degrees along the outer edge.   The arithmetic processing unit includes a correction unit that corrects an error of the signal output by the plurality of light receiving members, and the coordinates of the first axis of the input position based on the signal corrected by the correction unit. The optical touch panel according to claim 1, wherein the coordinates of the second axis are calculated.

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