JP4068365B2 - Coordinate input device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is used in electronic conferences, business presentations, education, and the like, and relates to an optical coordinate input device using laser light, such as an optical touch panel and an optical position detection device.
[0002]
[Prior art]
In an optical coordinate input device, light emitted from a laser diode (hereinafter referred to as LD) is often used as light used for the light source. Depending on the case (light intensity), this LD light may adversely affect the human body (eyes, etc.), so the light intensity is classified according to JIS and is used to inform the user of the contents. In accordance with safety standards, it is obliged to display on labels and manuals.
[0003]
When the light source unit used in the optical coordinate input device is LD light, the light is emitted to the outside of the device. Therefore, safety to the human body must be considered first, and the LD light used for the light source is a class. 1 is a condition. In addition, an optical unit is placed at each corner at the bottom of the screen, and the device that irradiates LD light in a fan shape around the corner provides sufficient margin for class 1 because LD light is diffused. It has a structure that does not adversely affect the human body.
[0004]
[Problems to be solved by the invention]
However, as shown above, in the conventional optical coordinate input device, the LD is damaged for some reason depending on the LD used, and the light (light destruction output) emitted at the time of the damage is very high output. May be. In such a case, class 1 may be exceeded, and in some cases, class 3 or 3B may be considered, and a safety measure that assumes such an accident is necessary.
[0005]
The present invention has been made in view of the above, and monitors the output of the LD light, maintains the operating state at the safety level, and cuts off the LD light emission above the predetermined level, thereby improving the safety. The purpose is to secure.
[0006]
[Means for Solving the Problems]
  In order to achieve the above object, the coordinate input device according to claim 1 is disposed at different positions on the touch panel and is substantially parallel to the touch surface.NaTwo light source units for emitting laser light, and laser light from the light source unitBeforeReflecting means for reflecting toward the light source section, light receiving means for receiving the light reflected by the reflecting means, and the touch panel based on the light receiving state of the light receiving meansofA coordinate detection unit that detects coordinates of a touched point, and a light intensity monitoring unit that receives the laser light and monitors the light intensity of the received light.BothOne optical unitAsFormedThe light intensity monitoring means has a light receiving surface inclined at a predetermined angle with respect to incident light.It is what.
[0007]
  According to the present invention, in the coordinate input device using the laser optical device, the laser light emitted from the light source is received in the optical unit and the light intensity is monitored, so that the output state of the laser light Can always be directly monitored, and optical monitoring that does not require extra space outside the optical unit is realized.Further, by disposing the light intensity monitoring means with the light receiving surface inclined at a predetermined angle with respect to the incident light, unnecessary surface reflected light from the surface of the light receiving element can be prevented from being input to the optical element.
[0010]
  Claims2In the coordinate input device according to the present invention, when the light reception level by the light intensity monitoring means is equal to or higher than a predetermined value, the power input means for shutting off the power supply to the light output power source of the light source unit is provided.
[0011]
According to this invention, when the light reception level of the light intensity monitoring means reaches a predetermined high output, it is possible to avoid outputting a high output laser beam by shutting off the power supply to the light source. It becomes possible.
[0012]
  Claims3In the coordinate input apparatus according to the above, the power shut-off means operates independently without interposing the control means of the apparatus main body.
[0013]
According to the present invention, the power shut-off means operates at the same time as the power is turned on by being configured to operate independently without intervention of the control means of the apparatus main body. For example, the control means of the apparatus main body runs out of control. Even when an abnormality such as time occurs, the light intensity monitoring means can monitor the laser beam without any influence.
[0014]
  Claims4In the coordinate input device according to the present invention, two light source units that are arranged at different positions on the touch panel, are substantially parallel to the touch surface, and emit laser light around the installation position, and laser light from the light source unit. Reflecting on the touch panel based on the light receiving state of the light receiving means, and a light receiving means for receiving the light reflected by the reflecting means; A coordinate detection unit that detects coordinates of a touched point, and the light source unit includes a laser output unit that outputs a laser beam, an LD drive unit that drives the laser output unit, and A power shut-off means for shutting off power to the laser output means and the drive means;,in frontOptical monitoring means for monitoring the output level of the laser output means, and the LD driving means for supplying an LD driving signal to the LD driving means and the power shut-off means, and generated based on a signal from the light monitoring means Control means for recognizing normal / abnormality of the output of the laser output means from the LD light emission signal, and for controlling to stop the output of the laser output means when abnormal,LD status recording means for recording information on the output status of the laser output means, and the control means writes to the LD status recording means regardless of whether the light emission status of the laser output means is normal or abnormal. Perform at regular intervalsIs.
[0015]
  According to the present invention, in the coordinate input device using the laser optical device, the output state of the laser light is monitored, the LD drive signal is supplied to the LD drive means and the power shut-off means, and based on the signal from the light monitoring means. The laser output means becomes abnormal by recognizing the normality / abnormality of the output of the laser output means from the LD light emission signal of the LD drive means generated in this way, and controlling to stop the output of the laser output means at the time of abnormality This makes it possible to cut off the power supply to the laser output means and the LD drive means.In addition, by writing to the LD state recording means at a constant cycle, even if the power of the apparatus main body is suddenly shut down, the previous LD state can be recognized after the power is restored.
[0018]
  Claims5In the coordinate input device according to the above, the control means performs an abnormal display after the recording operation of the LD state recording means.
[0019]
According to the present invention, after the recording operation of the LD state recording means, by displaying an abnormality, it is possible to record the abnormal state and inform the user of the abnormal state.
[0020]
  Claims6In the coordinate input device according toTwo light source units arranged at different positions on the touch panel, substantially parallel to the touch surface and emitting laser light around the installation position, and reflecting the laser light from the light source unit toward the light source unit Reflecting means for reflecting, light receiving means for receiving the light reflected by the reflecting means, and detecting the coordinates of touching and touching points on the touch panel based on the light receiving state of the light receiving means In the coordinate input device including the coordinate detection unit, the light source unit includes a laser output unit that outputs laser light, an LD drive unit that drives the laser output unit, and the laser output unit and the drive unit. A power shut-off means for shutting off the power; an optical monitoring means for monitoring the output level of the laser output means; an LD for the LD drive means and the power shut-off means; A normal signal / unusual output of the laser output means is recognized from an LD light emission signal of the LD driving means generated based on a signal from the light monitoring means, and an output of the laser output means is output when an abnormality occurs. Control means for controlling so as to stop the power supply, and the power shut-off means returns to the laser output means and the LD drive means again after the shut-off operation. Enable supplyIs.
[0021]
  According to this invention,In a coordinate input device using a laser optical device, an output state of laser light is monitored, an LD drive signal is supplied to an LD drive means and a power shut-off means, and LD drive generated based on a signal from the light monitor means By recognizing the normality / abnormality of the output of the laser output means from the LD light emission signal of the means, and controlling to stop the output of the laser output means at the time of abnormality, it is recognized that the laser output means has become abnormal, and the laser It becomes possible to cut off the power supply to the output means and the LD driving means. In particular,After the shut-off operation, it can be restored by turning on the power of the device again, and power can be supplied again to the laser output means and LD drive means, for example, laser output due to assembly failure in the production line, etc. If an abnormality occurs, it can be repaired and restored to normal operation by turning on the power again.
[0022]
  Claims7In the coordinate input device according toTwo light source units arranged at different positions on the touch panel, substantially parallel to the touch surface and emitting laser light around the installation position, and reflecting the laser light from the light source unit toward the light source unit Reflecting means for reflecting, light receiving means for receiving the light reflected by the reflecting means, and detecting the coordinates of touching and touching points on the touch panel based on the light receiving state of the light receiving means In the coordinate input device including the coordinate detection unit, the light source unit includes a laser output unit that outputs laser light, an LD drive unit that drives the laser output unit, and the laser output unit and the drive unit. A power shut-off means for shutting off the power; an optical monitoring means for monitoring the output level of the laser output means; an LD for the LD drive means and the power shut-off means; A normal signal / unusual output of the laser output means is recognized from an LD light emission signal of the LD driving means generated based on a signal from the light monitoring means, and an output of the laser output means is output when an abnormality occurs. Control means for controlling to stop the operation, and when the laser output means is abnormal, the control means can emit light after 100 seconds have elapsed regardless of device mode switching after the power is turned on again.Is.
[0023]
  According to this invention,In a coordinate input device using a laser optical device, an output state of laser light is monitored, an LD drive signal is supplied to an LD drive means and a power shut-off means, and LD drive generated based on a signal from the light monitor means By recognizing the normality / abnormality of the output of the laser output means from the LD light emission signal of the means, and controlling to stop the output of the laser output means at the time of abnormality, it is recognized that the laser output means has become abnormal, and the laser It becomes possible to cut off the power supply to the output means and the LD driving means. In particular,When the laser output means is abnormal,TheEven if the power is turned on again, by providing an interval of 100 seconds, it becomes possible to make the LD light accumulation amount for a certain period of time defined in the safety standard class 1 below the reference, and 100 seconds again by switching the device mode. No need to count.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of a coordinate input device according to the invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to this embodiment.
[0025]
FIG. 1 is an explanatory diagram showing a schematic configuration of a coordinate input device according to an embodiment of the present invention. This coordinate input device inputs the touch panel 101, the optical units 102L and 102R for detecting that the dedicated pen 106 has touched the touch panel 101, and the detection signals of the optical units 102L and 102R, and touched points (touch A system control unit 104 for calculating (point). The coordinates calculated by the system control unit 104 are input to a personal computer (hereinafter referred to as PC) 108 via the interface unit 105.
[0026]
In this embodiment, the dedicated pen 106 emits light as will be described later. The coordinate input device according to this embodiment includes a dedicated pen receiving unit 107 that receives light emitted from the dedicated pen 106 and inputs the light to the system control unit 104.
[0027]
The touch panel 101 includes reflectors 103a, 103b, and 103c that recursively reflect light on three sides excluding the side that coincides with the straight line connecting the optical units 102L and 102R. The light irradiated by the optical units 102L and 102R is recursively reflected by the reflectors 103a, 103b, and 103c, and received again by the optical units 102L and 102R.
[0028]
FIG. 2 is an explanatory diagram showing the configuration of the optical units 102L and 102R in FIG. The optical units 102L and 102R have the same configuration. FIGS. 2A and 2B show states viewed from directions different from each other by 90 degrees. The optical unit receives light reflected by a light source (hereinafter referred to as LD) 201, a lens unit 202 that diffuses light emitted from the light source 201 into a fan shape that requires the light source 201, and the reflectors 103a, 103b, and 103c. A light receiving lens 203 that condenses light, an optical element (hereinafter referred to as CCD) 204 that receives the light collected by the light receiving lens 203 and detects the presence or absence of a touch, and is disposed on the optical axis indicated by the alternate long and short dash line. A half mirror 205 for controlling the reflected light is provided.
[0029]
FIG. 3 is an explanatory diagram showing the configuration of the dedicated pen 106 in FIG. The dedicated pen 106 is supplied with electric power by contacting the battery 303, the battery 303, and a control unit 302 that turns on an LED (Light Emitting Diode) 305, and has elasticity, and the battery 303 and the control unit 302 are connected to each other. And a battery contact plate 304 to be brought into contact with or separated from.
[0030]
The battery contact plate 304 is pushed into the pen when the pen tip 301 is pressed to bring the battery 303 and the controller 302 into contact with each other. At this time, the LED 305 is turned on, and the lit optical signal is received by the dedicated pen receiver 107 wirelessly or by wire. When the pen tip 301 is no longer pressed, the direction returns to the pen tip 301 and the battery 303 and the control unit 302 are separated. With the above configuration, the dedicated pen generates an optical signal only when the pen tip is pressed.
[0031]
FIG. 4 is a block diagram showing the configuration of the control system of the coordinate input device in FIG. This control system includes optical units 102L and 102R, and an MBU (main board unit) 401 having a function that combines the system control unit 104 and the interface unit 105.
[0032]
The optical unit 102L is a substrate on which a light source (LD: laser diode) 201, an LDU (laser diode unit) 402 that is a substrate on which the light source 201 is mounted, an optical element (CCD: Charge Coupled Device) 204, and an optical element 204 are mounted. An SBU (sensor board unit) 403 is provided. Similarly, the optical unit 102R includes a light source 201, an LDU 402, an optical element 204, and a SUB 403.
[0033]
The MBU 401 includes a CPU 412 that controls the LDUs 402 and SBUs 403 of the optical units 102L and 102R, and calculates image coordinates of touch points by inputting image data taken by the CCD 204 output from the SBUs 403.
[0034]
The MBU 401 converts the analog data output from the shading memories 404 and 409 and the SBU 403 that store data serving as a reference for shading correction of the image data into digital data, or an image processing LSI (L 405, an image processing LSI (R) 407, a data storage memory L406 that stores analog data output from the SUB 403 for each line, a data storage memory R408, a ROM 410, a RAM 411, and an interface unit 105.
[0035]
In the above configuration, the shading memory 404, the image processing LSI (L) 405, and the data storage memory L406 process image data output from the SBU 403 of the optical unit 102L. The shading memory 409, the image processing LSI (R) 408, and the data storage memory R407 process the image data output from the SBU 403 of the optical unit 102R.
[0036]
The ROM 410 stores a program used for system control of the MBU 401. The ROM 410 is used as a work area for processing of the CPU 412. The interface unit 105 is incorporated in the MBU 401 and controls transmission / reception of signals between the MBU 401 and the external PC 108. In the configuration of FIG. 4, the RAM 411, the data storage memory L406, and the data storage memory R407 have different configurations. However, the RAM 411, the data storage memory L406, and the data storage memory R407 are configured by dividing one memory for each function. You can also
[0037]
Further, the MBU 401 is connected to the dedicated pen receiving unit 107. The dedicated pen receiving unit 107 receives an optical signal generated when the LED 305 of the dedicated pen 106 is turned on and inputs the received optical signal to the CPU 412. The MBU 401 detects contact and non-contact of the dedicated pen 106 with respect to the touch panel 101 based on the optical signal output from the LED 305.
[0038]
Next, a basic coordinate detection operation of the coordinate input device according to this embodiment will be described. The CPU 412 outputs an LD lighting signal that instructs the LDU 402 of the optical units 102L and 102R to light the LD 201 in accordance with the program read from the ROM 410. The LDUs 402 that have received the LD lighting signal each turn on the LD 201, and fan-shaped light is emitted onto the touch panel 101.
[0039]
The emitted light is recursively reflected by the reflectors 103a, 103b, and 103c and received by the CCD 204 of each of the optical units 102L and 102R. At this time, when the touch panel 101 is touched, the light passing through the touch point is blocked and is not received by the CCD 204 and is taken as an image. The captured image data is input to the image processing LSI (L) 405 and image processing LSI (R) 408 of the MBU 401 as image data, converted into digital data, and stored in the shading memories 404 and 409. The shading correction is performed using the existing data. The image data subjected to the shading correction is stored in the data storage memory L406 and the data storage memory R407.
[0040]
The CPU 412 reads the image data stored in the data storage memory L406 and the data storage memory R407, and detects a dip (a point at which the amount of light decreases) in the image data. Then, the coordinates of the touch point are calculated from the dip in the image data.
[0041]
Next, in the coordinate input device configured as described above, the LD light emitted from the light source (LD) 201 of each of the optical units 102L and 102R is monitored, and an abnormality in the LD is detected at an early stage, resulting from this. An example of solving the problem and ensuring safety will be described.
[0042]
In this embodiment, in order to monitor the LD light emitted from the light source (LD) 201 of each of the optical units 102L and 102R, the LD light is received by the light receiving element and the intensity thereof is detected. In this case, it is indispensable that the monitoring light receiving element is installed at a position where the LD light emitted in a fan shape and the light receiving line (coordinate detection line) of the light receiving unit (CCD) are not blocked. Since these lines are blocked, it is assumed that the above conditions are cleared. Hereinafter, a mounting example of the light receiving element will be described.
[0043]
(Implementation example 1)
FIG. 5 is an explanatory diagram showing a first arrangement configuration of the optical monitoring light-receiving elements of the optical system in the coordinate input device according to the embodiment of the present invention. Here, the light beam passing from the light source 102 through the lens unit 202 and deflected by the half mirror 205 is formed in the direction opposite to the light receiving line for forming an image on the optical element (CCD) 204 by the light receiving lens 203, that is, the half mirror 205 portion. The light monitoring light-receiving element 11 is arranged at a distance E at a position where the LD light in the C direction reflected by is incident.
[0044]
That is, in FIG. 5, the optical units 102L and 102R are structurally configured such that the LD light A emitted from the light source 201 passes through the lens unit 202 and is emitted to the outside of the unit as light B. At this time, due to the characteristics of the half mirror 205 used here, only 50% of the LD light A passes, and the remaining 50% of the light C is installed at a tilt of 45 degrees (angle θ1). Therefore, it is deflected in the C direction. Accordingly, the light monitoring light receiving element 11 is installed on the extension of the LD light in the C direction.
[0045]
As the light monitoring light receiving element 11, for example, a photodiode (Photo Diode) corresponding to the wavelength of the LD light of the light source 201 of the optical units 102L and 102R is used. As the reference voltage, voltage division by a resistor, a reference voltage IC, or the like is used.
[0046]
Accordingly, since the LD light emitted from the light source 102 is directly incident on the light monitoring light receiving element 11 and monitored, it is possible to monitor whether the intensity of the LD light is at a normal level or an abnormal level. it can. Further, by incorporating the light monitoring light receiving element 11 in each of the optical units 102L and 102R, the safety of the optical unit alone is ensured.
[0047]
(Mounting example 2)
FIG. 6 shows a case where the light-receiving element 11 for light monitoring is arranged at right angles to the incident LD light C. Generally, the light monitoring light receiving element 11 has a flat surface made of glass or the like. For this reason, the received light C is incident on the light monitoring light receiving element 11, and at the same time, there is light received by the light monitoring light receiving element 11 and light D reflected by the surface of the light monitoring light receiving element 11. At this time, due to the characteristics of the light-receiving element 11 for light monitoring (light from A to B passes, but light from B to A does not pass), the light passes through the half mirror 205 and the optical element ahead The optical element 204 becomes disturbing light and may cause erroneous detection in some cases. For this reason, in this embodiment, as shown in FIG. 7, the light monitoring light receiving element 11 is provided with an inclination angle.
[0048]
FIG. 7 is an explanatory diagram showing a second arrangement configuration of the light monitoring light receiving elements of the optical system in the coordinate input device according to the embodiment of the present invention. Here, the light monitoring light receiving element 11 is arranged so that the light D reflected by the surface of the light monitoring light receiving element 11 does not enter the optical element (CCD) 204. That is, as shown in FIG. 7, the light D reflected by the surface of the light monitoring light receiving element 11 is incident on the optical element (CCD) 204 without arranging the light monitoring light receiving element 11 at right angles to the optical path. The angle θ2 is set so as not to be installed.
[0049]
At this time, although depending on the configuration of the optical unit, in this embodiment, since the distance E (see FIG. 5) from the half mirror 205 to the light monitoring light receiving element 11 is about 5 mm, at least the angle θ2 is about 9 mm. .5 °. In addition, when the variation and margin of component accuracy are taken into consideration, the angle θ2 may be set on the brass side. Actually, the angle is set to 10 ° due to space limitations.
[0050]
Therefore, the reflected light on the surface of the light monitoring light receiving element 11 is made incident on the optical element (CCD) 204 by setting the light monitoring light receiving element 11 to be inclined with respect to the incident light. Therefore, erroneous detection by the optical element (CCD) 204 can be eliminated.
[0051]
By the way, if the LD light is to be obtained outside the optical units 102L and 102R, the light monitoring light receiving element 11 cannot be installed in the effective writing area 12, as shown in FIG. When installed, the light monitoring light receiving element 11 does not have reflection characteristics like a retroreflecting plate, so that the LD light is not reflected, and the optical element (CCD) 204 recognizes it as coordinates.
[0052]
FIG. 8 is an explanatory diagram showing the arrangement configuration of the optical monitoring light receiving elements of the optical system in the coordinate input device, and the light monitoring light receiving elements 11 are not arranged in the optical units 102L and 102R in the mounting example described above. The case configuration is shown. Here, for the reasons described above, the position where the light monitoring light-receiving element 11 is installed is outside the effective writing area 12, and is the point A or the point B as shown in FIG.
[0053]
Here, a comparison in the case where the light monitoring light receiving element 11 is arranged inside / outside the optical units 102L and 102R will be described with reference to FIG. In FIG. 9, the fan-shaped light 13 is thick and strong because of the relationship with the light source 102, but becomes weak because it becomes thin because it becomes an end portion. At this time, the installation inside the optical units 102L and 102R becomes the point D, while the outside installation becomes the point C.
[0054]
Therefore, when the light monitoring light receiving element 11 is installed inside the optical units 102L and 102R, a large and large output light can be obtained by installing the fan-shaped center, and a large amount of light can be obtained with respect to the area ratio of the LD light. Light can be received. Further, if the light receiving area of the light monitoring light receiving element 11 is large, more stable and strong light can be obtained.
[0055]
On the other hand, when the light-receiving element 11 for light monitoring is installed outside the optical units 102L and 102R, it receives light that is extremely unstable at the end of the fan-shaped light 13, and in some cases, the ambient light is brighter. In this case, there is a possibility that the light monitoring light receiving element 11 may receive erroneous light.
[0056]
As described above, when the light monitoring light-receiving element 11 is installed in the optical units 102L and 102R, it is a place where the ambient light is the least incident in the apparatus and is not affected. Further, the strongest light can be obtained at a position that does not block the LD light or the light receiving line in the device and is the closest to the light, so that the optimum arrangement position is obtained. Therefore, each of the optical units 102L and 102R is secured as a single unit, and classification according to safety standards can be applied.
[0057]
(Drive circuit for light monitoring element 11 for light monitoring)
Next, an example of a drive circuit for the above-described light monitoring light receiving element 11 will be described with reference to the block diagram shown in FIG.
[0058]
In FIG. 10, reference numeral 20 is a reference voltage, reference numeral 21 is a comparator, reference numeral 22 is a light source power source, reference numeral 23 is an analog circuit, and reference numeral 24 is a fuse. This drive circuit uses components that operate when the power is turned on without the calculation unit (system control unit 104), and when the calculation unit (system control unit 104) runs out of control, the light receiving element and the peripheral circuits are not operated. However, it is configured to operate as a safety circuit even when the CPU runs away.
[0059]
In the drive circuit configured as described above, when the light monitoring light receiving element 11 that constantly receives LD light receives high output LD light, a signal corresponding to the light receiving level is output. Are input to the comparator 21. In the comparator 21, a level to be cut off is set in advance as the reference voltage 20 with respect to the power supply to the light source 102. The comparator 21 compares the reference voltage 20 with the signal level from the light monitoring light receiving element 11. Here, when the signal level exceeds the reference voltage 20, the signal from the comparator 21 blows the fuse 24 through the analog circuit 23. As a result, the light source 102 supplied from the light source power source 22 is shut down and stopped operating, and light is not output from the light source 102.
[0060]
Therefore, when the LD light from the light source (LD) 102 is detected by the light monitoring light receiving element 11 and the level of the LD light exceeds a predetermined level, the power supply to the light source 102 is cut by the fuse 24, Even when the apparatus is turned on again, no power is supplied to the light source 102, and the abnormal or damaged light source 102 does not emit light again, so that safety can be ensured.
[0061]
(Power cutoff circuit system)
Next, an example in which the power source of the light source (LD) and its drive circuit is cut off when the LD light is abnormal will be described. FIG. 11 is a block diagram showing the configuration of the power shutoff circuit system in the coordinate input device according to the embodiment of the present invention.
[0062]
In FIG. 11, this power cutoff circuit system mainly includes a light source 201, a light monitoring unit 31, and a control unit 32. The light source 201 includes a power cutoff circuit 33, a drive circuit 34, and an LD 35. The light monitoring unit 31 has a light monitoring circuit 36. The control unit 32 includes a main control unit 37 having a timer 38, a recording medium 39, and a power holding circuit 40. The main control unit 37 may be realized by a CPU, and the internal timer 38 may be provided outside.
[0063]
The light monitoring circuit 36 is disposed in the optical unit as shown in FIG. The light monitoring circuit 36 monitors the output of the LD 35, monitors whether the LD light intensity is normal or abnormal, and sends an abnormal signal to the power cut-off circuit 33 in the case of abnormality. In the optical units 102L and 102R, the LD light A emitted from the light source 201 passes through the lens unit 202 and is emitted to the outside of the unit as light B due to its structure. At this time, due to the characteristics of the half mirror 205 used here, only 50% of the LD light A passes, and the remaining 50% of the light C is installed with the half mirror 205 inclined at 45 degrees (angle θ). Therefore, it is deflected in the C direction. Therefore, the light monitoring circuit 36 is installed on the extension of the LD light in the C direction.
[0064]
The light monitoring circuit 36 is arranged so that the light D reflected by the surface of the light receiving element does not enter the optical element (CCD) 204 as shown in FIG. That is, as shown in FIG. 12, the light D reflected by the surface of the light receiving element is not incident on the optical element (CCD) 204 without arranging the light receiving element of the light monitoring circuit 36 at right angles to the optical path. Install with a certain angle θ.
[0065]
In this way, by setting the surface of the light receiving element in the light monitoring circuit 36 at an angle θ, the LD light C again passes through the half mirror 205 and the lens 203 due to the surface reflection of the light receiving element, and the optical element. (CCD) 204 is prevented from entering and surface reflected light is released in the D direction. Thereby, erroneous detection in the optical element (CCD) 204 can be avoided.
[0066]
Next, a series of operations of the power cutoff circuit system configured as described above will be described. FIG. 13 is a flowchart showing the operation of the power shut-off circuit system in the coordinate input device according to the embodiment of the present invention.
[0067]
First, when the device is turned on (step S11), the main controller 37 and the optical unit are turned on (step S12). At this time, although the main control unit 37 operates by turning on the power, the optical unit does not operate the LD 35 and the drive circuit 34 by the power cutoff circuit 33. That is, the LD does not emit light.
[0068]
Subsequently, the main control unit 37 reads from the recording medium 39 the LD state information recorded when the device power is turned off during the previous device use (step S13), and whether the previous LD state is normal. Whether it is abnormal is determined (step 14). Here, if the content is an LD normal operation (no LD abnormality), an LD drive signal is output from the main control unit 37 (step S15), the power shut-off circuit 33 of the optical unit becomes non-shut off, and the LD 35 As soon as power is supplied to the drive circuit 34, an LD drive signal is input to the drive circuit 34, so that the LD 35 enters a light emitting state (step S16).
[0069]
Subsequently, it is determined whether or not the LD light emitted from the LD 35 is normal (step S17). If it is determined that the LD emission is normal, it is further determined whether the LD emission signal is normal (step S18). In this case, when the LD 35 emits light, an LD light emission signal from the drive circuit 34 is input to the main control unit 37, so that it is recognized whether or not the LD 35 is emitting light. If it is determined in step S18 that the LD emission signal is normal, writing to the recording medium 39 is performed (step S19).
[0070]
That is, since the LD light emission signal is not output when the LD 35 does not emit light, the main control unit 37 can always recognize the LD light emission state. Upon receiving this LD light emission signal, the LD state is always changed at a constant cycle. Write to the recording medium 39. In addition, this fixed period is so preferable that it is short.
[0071]
If it is determined in step S14 that the previous LD state read from the recording medium 39 is abnormal, the timer 38 counts for 100 seconds, for example (step S20), and the process proceeds to step S15.
[0072]
In step S17, for example, when it is determined that the output is higher than the normal light output value and the LD light emission is abnormal, the light output to the light monitoring circuit 36 is also increased. When the light monitoring circuit 36 receives LD light of a certain level or more, it detects it as an abnormality and outputs an abnormality signal to the power cutoff circuit 33. The power cutoff circuit 33 shuts off the power to the LD 35 and its drive circuit 34, The light emission of the LD 35 is stopped (step S21).
[0073]
After step S21, the LD emission signal is not output (step S22), and the abnormality of the LD 35 is recognized (step S23). Further, this abnormal state is written in the recording medium 39, the LD drive signal is not output (step S24), and LD abnormality display is performed (step S25). If the LD emission signal is abnormal (not output) in step S18, the process proceeds to step S23.
[0074]
Further, the above operation will be described. When the above-described light emission of the LD 35 is stopped, the drive circuit 34 whose power is cut off cannot output the LD light emission signal to the main control unit 37 because of the non-operation state. For this reason, as the state in the main control unit 37, although the LD drive signal is output, the LD light emission signal does not return, so it is recognized that the LD is abnormal, and the LD light emission state is changed at a constant cycle. This LD abnormality information is written in the recording medium 39 that is recorded, and then an abnormal state is displayed on the device screen to notify the user that an abnormality has occurred. By notifying the device screen of the abnormality, for example, when the user turns on the power again, the control unit 32 and the optical unit are turned on.
[0075]
When the power of the device is turned on again, if the LD light operates normally without any problem, the normal operation is executed as described above, and the recording medium 39 is rewritten from “LD abnormal” to “LD normal operation”. It is like that. In this case, for example, non-output and non-input of each LD signal due to poor connection of the harness in the assembling process is increased.
[0076]
In addition, when the device power supply suddenly turns off at the same time as the occurrence of the LD abnormality, normally, when attempting to write the LD abnormality to the recording medium 39, the device power supply is turned off so that writing can be performed. It may not be possible. For this reason, the power holding circuit 40 delays the power OFF to the main control unit 37 only during the time when the main control unit 37 recognizes the LD abnormal state and can write to the recording medium 39 from the device power OFF. Writing to the recording medium 39 is possible. The recording medium 39 is preferably, for example, an EEPROM so that the contents can be maintained even when the power of the device is turned on / off.
[0077]
Further, the power shut-off circuit 33 operates with a certain degree of margin from the class 1 reference so that the LD light does not exceed the standard class 1. In addition, the power shut-off circuit 33 can be restored by turning on the device power again after the shut-off, and at the time of shut-off, the signal from the main control unit 37 cannot be changed from the shut-off state to the non-cut-off state. It has become. The time of 100 seconds by the timer 38 is set because it aims to reduce the amount of LD light accumulated in 100 seconds in order to satisfy the same standard, but it satisfies the class 1. If so, the time may be less than 100 seconds.
[0078]
【The invention's effect】
  As described above, according to the coordinate input device according to the present invention (Claim 1), in the coordinate input device using the laser optical device, the laser light emitted from the light source is received in the optical unit. By adopting a configuration that monitors the light intensity, it becomes possible to always monitor the output state of the laser light directly, and light monitoring that does not require extra space outside the optical unit is realized. Therefore, it is possible to ensure the safety by the rapid processing.In particular, by disposing the light intensity monitoring means with the light receiving surface inclined at a predetermined angle with respect to incident light, it becomes possible to prevent unnecessary surface reflected light from the surface of the light receiving element from being input to the optical element. Generation of false detection can be avoided and a reliable laser beam level can be detected.
[0080]
  A coordinate input device according to the present invention (claims)2According to), when the light reception level of the light intensity monitoring means reaches a predetermined high output, it is possible to avoid outputting high output laser light by shutting off the power supply to the light source Therefore, safety can be secured quickly.
[0081]
  A coordinate input device according to the present invention (claims)3), The power shut-off means operates at the same time as the power is turned on by being configured to operate independently without the control means of the apparatus main body. For example, when the control means of the apparatus main body runs out of control Even when there is an abnormality such as, the light intensity monitoring means can monitor the laser light without any influence, so it is possible to always monitor the state of the laser light and ensure its safety it can.
[0082]
  A coordinate input device according to the present invention (claims)4), In the coordinate input device using the laser optical device, the output state of the laser beam is monitored, the LD drive signal is supplied to the LD drive means and the power shut-off means, and based on the signal from the light monitoring means The laser output means becomes abnormal by recognizing the normality / abnormality of the output of the laser output means from the LD light emission signal sent from the generated LD drive means, and controlling the output of the laser output means to stop when abnormal. This makes it possible to cut off the power supply to the laser output means and the LD drive means, so that the laser light can be surely turned off and the state where safety standards are exceeded is prevented. Can do.In particular, by writing to the LD status recording means at regular intervals, it becomes possible to recognize the previous LD status after power is restored even if the power supply of the apparatus body is suddenly shut down. It is possible to cope with safety.
[0084]
  A coordinate input device according to the present invention (claims)5), Since the abnormality display is performed after the recording operation of the LD state recording means, the abnormal state can be reliably recorded and the user can recognize the abnormal state.
[0085]
  A coordinate input device according to the present invention (claims)6)In a coordinate input device using a laser optical device, an output state of laser light is monitored, an LD drive signal is supplied to an LD drive means and a power shut-off means, and LD drive generated based on a signal from the light monitor means By recognizing the normality / abnormality of the output of the laser output means from the LD emission signal sent from the means, and controlling to stop the output of the laser output means at the time of abnormality, it is recognized that the laser output means has become abnormal. Since the power supply to the laser output means and the LD drive means can be cut off, the laser light can be surely turned off and the state where safety standards are exceeded can be prevented. In particular,After the shut-off operation, the device main body is restored by turning on the power again, and the power can be supplied again to the laser output means and the LD drive means. For example, the laser output caused by the assembly failure in the production line, etc. When an abnormality occurs, it can be repaired and restored to normal operation by turning on the power again.
[0086]
  A coordinate input device according to the present invention (claims)7)In a coordinate input device using a laser optical device, an output state of laser light is monitored, an LD drive signal is supplied to an LD drive means and a power shut-off means, and LD drive generated based on a signal from the light monitor means By recognizing the normality / abnormality of the output of the laser output means from the LD emission signal sent from the means, and controlling to stop the output of the laser output means at the time of abnormality, it is recognized that the laser output means has become abnormal. Since the power supply to the laser output means and the LD drive means can be cut off, the laser light can be surely turned off and the state where safety standards are exceeded can be prevented. In particular,When the laser output means is abnormal,TheEven when the power is turned on again, an interval of 100 seconds is provided, so that the LD light accumulation amount for a certain period of time stipulated in safety standard class 1 can be reduced below the standard, and 100 seconds is counted again by switching the device mode. There is no need to do it.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a schematic configuration of a coordinate input device according to an embodiment of the present invention.
2 is an explanatory diagram showing a configuration of an optical unit in FIG. 1. FIG.
3 is an explanatory diagram showing a configuration of a dedicated pen in FIG. 1. FIG.
4 is a block diagram showing a configuration of a control system of the coordinate input device in FIG. 1. FIG.
FIG. 5 is an explanatory diagram showing a first arrangement configuration of light monitoring elements for optical monitoring in the optical system in the coordinate input device according to the embodiment of the present invention;
FIG. 6 is an explanatory diagram showing a state where the light monitoring light receiving element 11 is arranged at a right angle with respect to the incident LD light C;
FIG. 7 is an explanatory diagram showing a second arrangement configuration of the optical monitoring light receiving elements of the optical system in the coordinate input device according to the embodiment of the present invention;
FIG. 8 is an explanatory diagram showing an arrangement configuration of light monitoring elements for optical monitoring of the optical system in the coordinate input device.
FIG. 9 is an explanatory diagram showing a comparative example in which light monitoring light-receiving elements are arranged inside / outside the optical unit.
FIG. 10 is a block diagram showing a configuration example of a drive circuit of a light receiving element for light monitoring.
FIG. 11 is a block diagram showing a configuration of a power cutoff circuit system in the coordinate input device according to the embodiment of the present invention.
FIG. 12 is an explanatory diagram showing an optical monitoring circuit arranged in the optical unit.
FIG. 13 is a flowchart showing the operation of the power shutoff circuit system in the coordinate input device according to the embodiment of the present invention;
[Explanation of symbols]
11 Light-receiving element for light monitoring
20 Reference voltage
21 Comparator
22 Power supply for light source
23 Analog circuit
24 fuse
33 Power-off circuit
34 Drive circuit
35 LD
36 Light monitoring circuit
37 Main control unit
38 timer
39 Recording media
101 Touch panel
102L, 102R Optical unit
103a-103c reflector
104 System control unit
201 Light source (LD)
204 Optical element
205 half mirror

Claims (7)

Are respectively disposed at different positions in the touch panel, and two light source unit for emitting a substantially parallel laser beam on the touch surface, a reflecting means for reflecting toward the front Symbol source unit the laser light from the light source unit, the reflecting means in the coordinate input device including a light receiving means for receiving light reflected, and a coordinate detecting means for detecting coordinates of points touched the touch panel is made based on the light receiving state of said light receiving means by,
The light source unit, receives the laser beam, both the light intensity monitoring means for monitoring the light intensity of the received light, is formed as one optical unit, the light intensity monitoring means, the incident light, the light receiving surface The coordinate input device is characterized in that is inclined at a predetermined angle . When light receiving level by the light intensity monitoring means is a predetermined value or more, the coordinate input device according to claim 1, characterized in that with a power cutoff means for cutting off the power supply to the optical output power of the light source unit . The coordinate input device according to claim 2 , wherein the power shut-off means operates independently without interposing a control means of the apparatus main body. Two light source units arranged at different positions on the touch panel, substantially parallel to the touch surface and emitting laser light around the installation position, and reflecting the laser light from the light source unit toward the light source unit Reflecting means for reflecting, light receiving means for receiving the light reflected by the reflecting means, and detecting the coordinates of touching and touching points on the touch panel based on the light receiving state of the light receiving means In a coordinate input device comprising a coordinate detection means,
The light source unit includes laser output means for outputting laser light, LD drive means for driving the laser output means, power supply cutoff means for cutting off power to the laser output means and the drive means ,
An optical monitoring means for monitoring the output level of the previous SL laser output means,
An LD drive signal is supplied to the LD drive means and the power shut-off means, and normality / abnormality of the output of the laser output means from an LD emission signal of the LD drive means generated based on a signal from the light monitoring means Control means for recognizing and controlling to stop the output of the laser output means when abnormal,
LD state recording means for recording information of the output state of the laser output means;
With
The coordinate input device according to claim 1, wherein the control means performs writing to the LD state recording means at a constant cycle regardless of whether the light emission state of the laser output means is normal or abnormal . 5. The coordinate input device according to claim 4 , wherein the control means displays an abnormality after the recording operation of the LD state recording means. Two light source units arranged at different positions on the touch panel, substantially parallel to the touch surface and emitting laser light around the installation position, and reflecting the laser light from the light source unit toward the light source unit Reflecting means for reflecting, light receiving means for receiving the light reflected by the reflecting means, and detecting the coordinates of touching and touching points on the touch panel based on the light receiving state of the light receiving means In a coordinate input device comprising a coordinate detection means,
The light source unit includes laser output means for outputting laser light, LD drive means for driving the laser output means, power supply cutoff means for cutting off power to the laser output means and the drive means,
Light monitoring means for monitoring the output level of the laser output means;
An LD drive signal is supplied to the LD drive means and the power shut-off means, and normality / abnormality of the output of the laser output means from an LD emission signal of the LD drive means generated based on a signal from the light monitoring means Control means for recognizing and controlling to stop the output of the laser output means when abnormal,
With
The power supply breaker after the breaking operation, returns with restoring power to the device body, again, the coordinate input device, characterized in that to enable the supply of power to the lasers output means and the LD driving unit . Two light source units arranged at different positions on the touch panel, substantially parallel to the touch surface and emitting laser light around the installation position, and reflecting the laser light from the light source unit toward the light source unit Reflecting means for reflecting, light receiving means for receiving the light reflected by the reflecting means, and detecting the coordinates of touching and touching points on the touch panel based on the light receiving state of the light receiving means In a coordinate input device comprising a coordinate detection means,
The light source unit includes laser output means for outputting laser light, LD drive means for driving the laser output means, power supply cutoff means for cutting off power to the laser output means and the drive means,
Light monitoring means for monitoring the output level of the laser output means;
An LD drive signal is supplied to the LD drive means and the power shut-off means, and normality / abnormality of the output of the laser output means from an LD emission signal of the LD drive means generated based on a signal from the light monitoring means Control means for recognizing and controlling to stop the output of the laser output means when abnormal,
With
The coordinate input device according to claim 1, wherein when the laser output unit is abnormal, the control unit can emit light after 100 seconds have elapsed regardless of the device mode switching after the power is turned on again .

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