JP2015133061A - Coordinate detection system, coordinate detection device, and light intensity adjustment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coordinate detection device that adjusts light emitted from an electronic pen to light intensity able to perform a highly accurate coordinate detection.SOLUTION: A coordinate detection device according to an embodiment of the present invention is a coordinate detection device that detects a coordinate designated by a designation unit on the basis of an optical signal emitted by the designation unit executing a designation operation to a board surface, and the coordinate detection device solves the problem described above by including: a plurality of optical signal input means to which the optical signal is input; extraction means for extracting a prescribed optical signal from the optical signal input by the optical signal input means; measurement means for measuring light intensity of the prescribed optical signal on the basis of the prescribed optical signal extracted by the extraction means; and control means for controlling light intensity of the optical signal emitted by the designation unit on the basis of the light intensity of the prescribed optical signal measured by the measurement means.

Description

  The present invention relates to a coordinate detection system, a coordinate detection device, and a light intensity adjustment method.

  In recent years, optical (blocking, light emitting, etc.) coordinate detection is used in touch panels, liquid crystal integrated tablets, electronic boards, and the like. In the blocking method, the coordinates are detected by detecting that the light emitted from the light emitting unit is blocked by the coordinate support unit (electronic pen, hand, etc.) by the light receiving unit. In the light emission method, a light emitting unit (LED: Light Emitting Ddiode, retroreflective material, etc.) is attached to the coordinate support unit, and the light is emitted from the light emitting unit, and the light receiving unit detects the coordinates.

  A precise optical axis can be obtained by inserting an indicating means into a coordinate detection area where light is emitted from the light emitting means, and detecting the two-dimensional coordinate position of the indicating means based on the imaging position of each imaging device. A coordinate detection apparatus that does not require alignment is disclosed (for example, see Patent Document 1).

  When using coordinate detection of the light emitting method, it is preferable to perform coordinate detection with high accuracy by adjusting the light intensity of the light emitting unit based on the distance between the electronic pen (light emitting unit) and the optical sensor. However, it is difficult to optimize the light intensity of the light emitting unit according to all the optical sensors (four or more) provided on the electronic board.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a coordinate detection device that adjusts light emitted from an electronic pen to a light intensity capable of performing coordinate detection with high accuracy. To do.

  The coordinate detection apparatus according to the present embodiment is a coordinate detection apparatus that detects coordinates instructed by an instruction unit based on an optical signal emitted by an instruction unit that performs an instruction operation on a board surface. A plurality of optical signal input means, an extraction means for extracting a predetermined optical signal from the optical signal input by the optical signal input means, and a predetermined light based on the predetermined optical signal extracted by the extraction means; Measuring means for measuring the light intensity of the signal, and control means for controlling the light intensity of the optical signal emitted by the instruction unit based on the light intensity of the predetermined optical signal measured by the measuring means, Is a requirement.

  According to the embodiment of the present invention, it is possible to provide a coordinate detection device that adjusts light emitted from an electronic pen to a light intensity that enables highly accurate coordinate detection.

It is a figure which illustrates the coordinate detection apparatus which concerns on this embodiment. It is a figure which illustrates the coordinate detection apparatus which concerns on Embodiment 1. FIG. It is a figure explaining the process sequence of the coordinate detection which concerns on Embodiment 1. FIG. It is a figure explaining white light emission which uses LED. FIG. 10 is a diagram illustrating a waveform pattern of an optical signal according to the second embodiment. It is a figure which illustrates the coordinate detection apparatus which concerns on Embodiment 2. FIG. It is a figure explaining the processing procedure of the coordinate detection which concerns on Embodiment 2. FIG. It is a figure which illustrates the system configuration | structure of the coordinate detection system which concerns on Embodiment 3. FIG. FIG. 10 is a diagram illustrating a hardware configuration of a computer according to a fourth embodiment.

  Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings and tables. In the drawings, the same components are denoted by the same reference numerals, and redundant description may be omitted.

<First Embodiment>
In FIG. 1, an example of schematic structure of the coordinate detection apparatus 100 which concerns on this Embodiment is shown. The coordinate detection device 100 is an optical coordinate detection device.

  The coordinate detection apparatus 100 includes an electronic board (board surface) 110, an electronic pen (instruction unit) 120, and sensors 130, 140, 150, and 160 (a plurality of optical signal input units).

  The electronic pen 120 exists in the electronic board 110 and performs an instruction operation on the electronic board 110. The sensor 130, the sensor 140, the sensor 150, and the sensor 160 are optical sensors for coordinate detection, and are provided at corners (four locations) of the electronic board 110. The number of optical sensors is not particularly limited, but at least four or more are preferably provided on the electronic board 110.

  For example, in FIG. 1, the frequency of the signal corresponding to the sensor 130 is Fa [Hz], the frequency of the signal corresponding to the sensor 140 is Fb [Hz], the frequency of the signal corresponding to the sensor 150 is Fc [Hz], and the sensor 160. Assume that the frequency of the signal corresponding to is Fd [Hz]. The frequency of the signal corresponding to each sensor may be the same or different.

  In any case, the coordinate detection apparatus 100 converts the light emitted from the electronic pen 120 to each optical based on the distance information (distance between the electronic pen 120 and each sensor) acquired from each optical sensor. It can be adjusted to the optimum light intensity according to the sensor.

  Next, an example of a coordinate detection method in the coordinate detection apparatus 100 will be described with reference to FIGS. FIG. 3 is an example of a flowchart in the case of performing coordinate detection using the coordinate detection apparatus 100 shown in FIG.

  In FIG. 3, immediately after the start, the electronic pen cannot acquire distance information from the optical sensor, and therefore selects a default phosphor. If the electronic pen is turned off during the process, the process is temporarily terminated. The case where the switch is turned off during the process is not shown because the figure becomes complicated.

  In the coordinate detection apparatus 100 shown in FIG. 2, the electronic pen 120 includes a light intensity measurement unit 121, a phosphor determination unit 122, a phosphor selection unit 123, a phosphor 124, and an ultraviolet LED 125. Part 170.

  Between the phosphor selection unit 123 and the spectroscopic / reflection processing unit 170, the amplitude of white light is attenuated. Further, the amplitude of monochromatic light (four types) is attenuated between the spectroscopic / reflection processing unit 170 and the light intensity measurement unit 121.

  The light intensity measurement unit 121 includes an optical filter, a voltage conversion unit, an intensity measurement unit, and the like. The same number of optical filters, voltage converters, and intensity measuring units as the sensors provided on the electronic board 110 are provided (four in FIG. 2). For example, a photodiode or the like can be used as the voltage conversion unit.

  The light intensity measurement unit 121 passes the monochromatic light (predetermined optical signal) extracted from the spectroscopic / reflection processing unit (extraction means) 170 through an optical filter, and the monochromatic light is applied to the corresponding monochromatic light (to the corresponding sensor). It is determined whether it is a corresponding predetermined optical signal).

  Further, when the light intensity measuring unit 121 determines that the extracted monochromatic light is the corresponding monochromatic light, the light intensity measuring unit 121 performs voltage conversion on the light with the voltage converting unit. On the other hand, when the light intensity measurement unit 121 determines that the extracted monochromatic light is not the corresponding monochromatic light, the light conversion unit 121 does not perform voltage conversion on the light at the voltage conversion unit.

  Further, the light intensity measuring unit (measuring means) 121 measures the intensity of the monochromatic light (analog voltage value) subjected to voltage conversion by the intensity measuring unit and outputs it as a light intensity signal (digital signal) (FIG. 3). (See S201). The light intensity measurement may be performed by the light intensity measurement unit 121 provided inside the electronic pen, or may be performed by a measurement unit (not shown) provided outside the electronic pen (inside the coordinate detection device). good.

  Note that the maximum amplitude of the monochromatic light changes depending on the intensity of the monochromatic light subjected to voltage conversion. Since the amplitude of the monochromatic light is attenuated based on the distance between the spectroscopic / reflection processing unit 170 and the light intensity measuring unit 121, the amplitude of the monochromatic light is attenuated in accordance with the light intensity measured by the intensity measuring unit. It is possible to determine the degree (degree) to do.

  The phosphor determining unit 122 acquires distance information (distance between each sensor and the electronic pen 120) from a plurality (four) of light intensity signals input from the light intensity measuring unit 121, and uses the distance information as the distance information. Based on this, it is determined which phosphor should be selected. Further, the phosphor determining unit 122 outputs the determination result as a phosphor select signal (digital signal) to the phosphor selecting unit 123 (see S202 in FIG. 3).

  The phosphor selection unit 123 outputs white light (selected white light) to be output based on the phosphor selection signal input from the phosphor determination unit 122 and the white light emitted from the phosphor 124 ( The white light that should not be output is masked (see S203 in FIG. 3). The phosphor selection unit (control unit) 123 controls the light intensity of the optical signal emitted by the instruction unit based on the light intensity of the predetermined optical signal measured by the light intensity measurement unit 121. The light intensity may be controlled by the phosphor selection unit 123 provided inside the electronic pen, or by control means (not shown) provided outside the electronic pen (inside the coordinate detection device). May be.

  The phosphor 124 passes the ultraviolet light emitted from the ultraviolet LED 125 through each phosphor (phosphor_α1 to phosphor_αN), and emits light (mixed light) equivalent to light obtained by multiplexing a plurality of monochromatic lights. . The number of the phosphors 124 is not particularly limited, and may be set as appropriate in consideration of the adjustment condition of the mixed light, the mounting convenience (area, cost, etc.) of the electronic pen.

  Note that by using phosphors of different materials as phosphor_α1 to phosphor_αN, light emitted from each phosphor can be made different from each other. In other words, if the light emitted from each phosphor is frequency-division-divided, monochromatic light such as red, green, yellow, and blue can be obtained, but if phosphors of different materials are used, a plurality of lights having different light intensities can be obtained. can get.

  The ultraviolet LED 125 emits ultraviolet light and irradiates the phosphor 124. By combining the ultraviolet LED 125 and the phosphor 124, white light can be generated. The generation of white light is not particularly limited to the combination of an ultraviolet LED and a phosphor. For example, as shown in FIG. 4A, a blue LED, a green LED, and a red LED may be combined to generate white light by adjusting the intensity of each LED. For example, as shown in FIG. 4B, white light may be generated by a combination of a blue LED and a yellow phosphor.

  Note that when white light is generated by combining an ultraviolet LED and a phosphor, the configuration can be simplified as compared with the case of FIGS. 4A and 4B, and the cost can be relatively reduced. , Etc. have the advantages.

  The spectroscopic / reflection processing unit 170 multiplexes the optical signal (white light) input from the phosphor selection unit 123 based on frequency division, and extracts specific monochromatic light (predetermined optical signal). The spectroscopic / reflection processing unit 170 outputs the extracted monochromatic light to the light intensity measurement unit 121 (see S204 in FIG. 3). That is, the spectroscopic / reflection processing unit 170 feeds back the extracted monochromatic light to the light intensity measuring unit 121 (the amplitude of the fed monochromatic light is attenuated). As a result, the electronic pen 120 can recognize to which sensor the four types of monochromatic light correspond, and can recognize the light intensity of the four types of monochromatic light.

  The spectroscopic / reflection processing units 170 are provided in the vicinity of each sensor, and are provided in the same number as each sensor. By multiplexing the optical signal (white light) input from the phosphor selection unit 123 based on the frequency division by the spectroscopic / reflection processing unit 170, it is possible to simultaneously transmit and receive the optical signal.

  The amplitude of the white light input from the phosphor selection unit 123 is attenuated based on the distance between the phosphor selection unit 123 and the spectroscopic / reflection processing unit 170. The spectroscopic / reflection processing unit 170 splits the attenuated white light. Therefore, the monochromatic light output from the spectroscopic / reflection processing unit 170 is light that depends on the distance between the phosphor selection unit 123 and the spectroscopic / reflection processing unit 170.

  According to the coordinate detection apparatus 100 according to the present embodiment, four or more sensors provided on the electronic board 110 (board surface) extract a predetermined optical signal and send distance information and the like to the electronic pen 120 (instruction unit). Feedback to Since the electronic pen 120 emits light whose light intensity is optimized according to all the sensors based on the distance information, the coordinate detection apparatus 100 can perform highly accurate coordinate detection.

<Second Embodiment>
In the present embodiment, a coordinate detection apparatus having a configuration different from that of the first embodiment will be described. In the present embodiment, coordinate detection is performed using an optical signal multiplexed based on time division.

  FIG. 5 shows a waveform pattern of an optical signal in the coordinate detection apparatus according to the present embodiment. The waveform pattern of the optical signal includes an area recognition pattern and a pen coordinate detection pattern.

  FIG. 5A shows an area recognition pattern and a pen coordinate detection pattern in a case where the use area is a time area of only ¼ of one cycle. The region recognition pattern is a pattern in which the number of peaks is adjusted in order to determine which sensor corresponds to the optical signal. The pen coordinate detection pattern is a pattern in which the duty width is adjusted for light intensity adjustment. A waveform pattern using only a quarter of one period shown in FIG. 5A is multiplexed on the basis of time division to obtain a waveform pattern shown in FIG. 5B, thereby corresponding to each sensor. Coordinate detection can be performed using the waveform pattern.

  For example, as shown in FIG. 5B, the region recognition pattern corresponding to the sensor 130 is a waveform pattern having one peak. Further, for example, as shown in FIG. 5B, the region recognition pattern corresponding to the sensor 140 is a waveform pattern having two peaks. For example, as shown in FIG. 5B, the region recognition pattern corresponding to the sensor 150 is a waveform pattern having three peaks. For example, as shown in FIG. 5B, the region recognition pattern corresponding to the sensor 160 is a waveform pattern having four peaks.

  Further, for example, as shown in FIG. 5B, the pattern in which the duty widths corresponding to the sensors 130 and 160 are adjusted is compared with the pattern in which the duty widths corresponding to the sensors 140 and 150 are adjusted. The width becomes wider. Further, for example, as shown in FIG. 5B, the pattern in which the duty width corresponding to the sensor 140 is adjusted has the narrowest duty width among the sensors. Further, for example, as shown in FIG. 5B, the pattern in which the duty width corresponding to the sensor 150 is adjusted has a larger duty width than the pattern in which the duty width corresponding to the sensor 140 is adjusted. Compared with the pattern in which the duty width corresponding to 130 and the sensor 160 is adjusted, the duty width becomes narrower.

  Next, an example of a coordinate detection method in the coordinate detection apparatus 100 will be described with reference to FIGS. 6 and 7. FIG. 7 is an example of a flowchart when coordinate detection is performed using the coordinate detection apparatus 100 shown in FIG.

  In FIG. 7, immediately after the start, the electronic pen cannot acquire distance information from the optical sensor, and therefore selects a default duty. If the electronic pen is turned off during the process, the process is temporarily terminated. The case where the switch is turned off during the process is not shown because the figure becomes complicated.

  In the coordinate detection apparatus 100 shown in FIG. 6, the electronic pen 120 includes a light intensity measurement / duty adjustment unit 321 and a multiplexing processing unit 322, and each sensor includes a specific waveform extraction unit 323.

  The optical signal (after division) is attenuated between the light intensity measurement / duty adjustment unit 321 and the specific waveform extraction unit 323.

  The light intensity measurement / duty adjustment unit 321 includes a voltage conversion unit, a pattern determination unit, an intensity determination unit, a duty adjustment unit, and the like. The voltage conversion unit, the pattern determination unit, the intensity determination unit, and the duty adjustment unit are provided in the same number as the sensors provided on the electronic board 110 (four in FIG. 6). For example, a photodiode or the like can be used as the voltage conversion unit.

  The light intensity measurement / duty adjustment unit 321 converts the voltage of the predetermined optical signal extracted from the specific waveform extraction unit 323 at the voltage conversion unit. Further, the light intensity measurement / duty adjustment unit 321 uses the pattern discrimination unit to convert the region recognition pattern of the optical signal subjected to voltage conversion into a corresponding region recognition pattern (a region in a predetermined optical signal corresponding to the corresponding sensor). It is determined whether the pattern is a recognition pattern). When the light intensity measurement / duty adjustment unit 321 determines that the region recognition pattern is a corresponding pattern, the intensity determination unit measures the amplitude of the pen coordinate detection pattern and determines the light intensity. On the other hand, when the light intensity measurement / duty adjustment unit 321 determines that the region recognition pattern is not a corresponding pattern, the intensity determination unit does not measure the amplitude of the pen coordinate detection pattern, and determines the light intensity. Not determined.

  Further, the light intensity measurement / duty adjustment unit 321 adjusts the duty width of the pen coordinate detection pattern to an optimum width by the duty adjustment unit based on the determined intensity. The light intensity measurement / duty adjustment unit 321 outputs the electrical signal (after the duty adjustment) with the duty width adjusted to the optimum width to the multiplexing processing unit 322 (see S301 in FIG. 7).

  Since the amplitude of the light is attenuated based on the distance between the specific waveform extraction unit 323 and the light intensity measurement / duty adjustment unit 321, the degree (degree) of attenuation of the light amplitude is determined by the intensity determination unit. Is possible.

  The multiplexing processing unit 322 multiplexes the electric signal (after duty adjustment) input from the light intensity measurement / duty adjustment unit 321 based on time division, and generates a specific waveform extraction unit 323 as an optical signal (after multiplexing). (See S302 in FIG. 7). That is, the multiplexing processing unit 322 multiplexes the electrical signal adjusted to the optimum light intensity according to all the sensors, converts it into an optical signal, and outputs it.

  The specific waveform extraction unit 323 includes a pattern through / mask processing unit, a pattern determination unit, and the like. The same number of pattern through / mask processing units and pattern discrimination units as the number of sensors are provided.

  The specific waveform extraction unit 323 determines whether the optical signal (after multiplexing) input from the multiplexing processing unit 322 is a pattern of the corresponding sensor region at the pattern determination unit. When the specific waveform extraction unit 323 determines that the optical signal is a pattern of the corresponding sensor region, the pattern through / mask processing unit causes the optical signal to pass through and output (see S303 in FIG. 7). ). On the other hand, when the specific waveform extraction unit 323 determines that the optical signal is not a pattern of the corresponding sensor region, the pattern signal is masked and not output by the pattern through / mask processing unit.

  Based on the distance between the multiplexing processing unit 322 and the specific waveform extraction unit 323, the amplitude of the light is attenuated. Since the specific waveform extraction unit 323 outputs a specific time region of the attenuated light as a predetermined optical signal, the signal includes light that depends on the distance between the multiplexing processing unit 322 and the specific waveform extraction unit 323. Become.

  Note that the corresponding region recognition pattern can be pre-read and set in advance. When the specific waveform extraction unit 323 determines whether to mask the optical signal or pass through the optical signal after reading the corresponding region recognition pattern, the region recognition pattern is used as the light intensity measurement / duty. It cannot be transmitted to the adjustment unit 321. However, if it is assumed that the pattern of the sensor 130, the pattern of the sensor 140, the pattern of the sensor 150, and the pattern of the sensor 160 are multiplexed in order, the corresponding region recognition pattern is set in advance, The area recognition pattern can be transmitted to the light intensity measurement / duty adjustment unit 321. For example, if the area recognition pattern of the sensor 160 is recognized, the control may be performed such that the area recognition pattern of the sensor 130 is passed. Thereby, it is possible to improve the detection accuracy of a coordinate detection apparatus.

<Third Embodiment>
In the present embodiment, a coordinate detection system using the coordinate detection apparatus according to the first embodiment will be described. FIG. 8 shows an example of the system configuration of the coordinate detection system according to the present embodiment.

  The coordinate detection system 500 includes a display 200, four detection units 11a to 11d (in the case of indicating any one or more detection units, simply referred to as the detection unit 11), and four peripheral light emitting units 15a to 15d (any one or more detection units). When the detection unit is shown, it is simply referred to as a peripheral light emitting unit 15), a computer 100, and a PC (Personal Computer) 300 as an additional element. Since the four peripheral light emitting units 15a to 15d are unnecessary in the embodiment of the present invention, detailed description thereof is omitted.

  A PC is connected to the computer 100, and the computer 100 can display an image output from the PC 300 on the display 200.

  An application corresponding to the coordinate detection system 500 is installed in the computer 100, and the application detects a position operated by the user based on a signal from the detection unit. The application analyzes the gesture based on the position and controls the computer 100. The application can display an operation menu on the display 200.

  For example, when the user touches a menu for drawing a line and then draws a figure on the board surface of the display 200 with an indicator 13 such as an electronic pen having a light emitting unit, the computer 100 uses the light from the light emitting unit that the indicator 13 has. Based on the above, the position touched by the pointing tool 13 is analyzed in real time to generate time-series coordinates. The computer 100 connects the time-series coordinates to create a line and displays it on the display 200. In FIG. 8, since the user has moved the pointing tool 13 along the shape of a triangle, the computer 100 records a series of coordinates as one stroke (triangle). Then, it is combined with the image of the PC 300 and displayed on the display 200.

  Thus, even if the display 200 does not have a touch panel function, by applying the coordinate detection system 500, the user can perform various operations by simply touching the display 200 with the pointing tool 13.

<Fourth embodiment>
In the present embodiment, a computer that is applied to a coordinate detection system using the coordinate detection apparatus according to the first embodiment will be described. FIG. 9 shows an example of the hardware configuration of the computer.

  The computer 2100 is an information processing apparatus developed for a commercially available information processing apparatus or coordinate detection system. A computer 2100 includes a CPU 2101, a ROM 2102, a RAM 2103, an SSD 2104, a network controller 2105, an external storage controller 2106, a sensor controller 2114, a GPU 2112, and a capture device that are electrically connected via a bus line 2118 such as an address bus or a data bus. 2111.

  The CPU 2101 executes an application and controls the overall operation of the coordinate detection system. The ROM 2102 stores IPL and the like, and mainly stores programs executed by the CPU 2101 at startup. The RAM 2103 is a work area when the CPU 2101 executes an application. The SSD 2104 is a nonvolatile memory in which an application 2119 for the coordinate detection system and various data are stored. The network controller 2105 performs processing based on a communication protocol when communicating with a server or the like via a network (not shown). The network is a LAN or a WAN (for example, the Internet) to which a plurality of LANs are connected.

  The external storage controller 2106 performs writing to or reading from the removable external memory 2117. The external memory 2117 is, for example, a USB memory or an SD card. The capture device 2111 captures (captures) video displayed on the display device by the PC 2300. The GPU 2112 is a drawing-dedicated processor that calculates the pixel value of each pixel of the display. The display controller 2113 outputs the image created by the GPU 2112 to the display.

  Four detection units 2211a to 2211d are connected to the sensor controller 2114, and coordinates are detected by a triangulation method based on light from a light emitting unit included in the pointing tool 2213. Details will be described later.

  In this embodiment, the computer 2100 does not need to communicate with the pointing tool 2213, but may have a communication function. In this case, as shown in the figure, the computer 2100 has an electronic pen controller 2116 and receives a pressing signal from the pointing tool 2213 (when the pointing tool 2213 has a notification means). Thereby, the computer 2100 can detect whether or not the tip is pressed.

  The application for the coordinate detection system may be distributed while being stored in the external memory 2117, or may be downloaded from a server (not shown) via the network controller 2105. The application may be compressed or executable.

  The preferred embodiment of the present invention has been described in detail above, but the present invention is not limited to the specific embodiment, and within the scope of the gist of the embodiment of the present invention described in the claims, Various modifications and changes are possible.

100 Coordinate detection device 110 Electronic board (board surface)
120 Electronic pen (instruction unit)
121 Light intensity measuring unit (measuring means)
123 Phosphor selection unit (control means)
124 phosphor 125 UV LED
130, 140, 150, 160, sensor (light signal input means)
170 Spectroscopic / reflection processing unit (extraction means)
500 Coordinate detection system

JP 2001-290603 A

Claims (15)

A coordinate detection system that detects coordinates instructed by the instruction unit based on an optical signal emitted by an instruction unit that performs an instruction operation on a board surface,
A plurality of optical signal input means for inputting the optical signal;
Extraction means for extracting a predetermined optical signal from the optical signal input by the optical signal input means;
Measuring means for measuring the light intensity of the predetermined optical signal based on the predetermined optical signal extracted by the extracting means;
A coordinate detection system comprising: control means for controlling the light intensity of the optical signal emitted by the indicator based on the light intensity of the predetermined optical signal measured by the measuring means.   The coordinate detection system according to claim 1, wherein the optical signal is multiplexed based on frequency division.   The coordinate detection system according to claim 1, wherein the optical signal is multiplexed based on time division.   The coordinate detection system according to claim 1, wherein the instruction unit generates white light by combining one ultraviolet LED and a plurality of phosphors.   The coordinate detection system according to any one of claims 1 and 2, wherein the instruction unit generates white light by combining a red LED, a green LED, and a blue LED.   The coordinate detection system according to claim 3, wherein the waveform pattern of the optical signal includes a region recognition pattern and a coordinate detection pattern.   The coordinate detection system according to claim 6, wherein the region recognition pattern is preset. A coordinate detection device that detects coordinates instructed by the instruction unit based on an optical signal emitted by an instruction unit that performs an instruction operation on a board surface,
A plurality of optical signal input means for inputting the optical signal;
Extraction means for extracting a predetermined optical signal from the optical signal input by the optical signal input means;
Measuring means for measuring the light intensity of the predetermined optical signal based on the predetermined optical signal extracted by the extracting means;
A coordinate detection apparatus comprising: control means for controlling the light intensity of the optical signal emitted by the instruction unit based on the light intensity of the predetermined optical signal measured by the measurement means.   The coordinate detection apparatus according to claim 8, wherein the optical signal is multiplexed based on frequency division.   The coordinate detection apparatus according to claim 8, wherein the optical signal is multiplexed based on time division.   The coordinate detection apparatus according to claim 8, wherein the instruction unit generates white light by combining one ultraviolet LED and a plurality of phosphors.   The coordinate detection device according to claim 8, wherein the instruction unit generates white light by combining a red LED, a green LED, and a blue LED.   The coordinate detection apparatus according to claim 10, wherein the waveform pattern of the optical signal includes a region recognition pattern and a coordinate detection pattern.   The coordinate detection device according to claim 13, wherein the region recognition pattern is preset. An optical signal adjustment method in a coordinate detection device that detects coordinates instructed by an instruction unit based on an optical signal emitted by an instruction unit that performs an instruction operation on a board surface,
A step of inputting the optical signal to a plurality of optical signal input means;
Extracting a predetermined optical signal from the optical signal input by the optical signal input means;
Measuring the light intensity of the predetermined optical signal based on the extracted predetermined optical signal;
Controlling the light intensity of the optical signal emitted by the instruction unit based on the measured light intensity of the predetermined optical signal.

Images