JP2001043019A - Coordinate detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coordinate detector capable of improving the reliability in self-diagnosis and accuracy in coordinate detection by performing the self- diagnosis and shading correction by using more suitable reference data. SOLUTION: This device has optical units 102A and 102B for emitting light onto the surface of a touch panel 101 and receiving the reflected light of the emitted light, reflecting members 103A-103C for reflecting the emitted light and generating reflected light toward the optical units 102A and 102B and an arithmetic part 104 for detecting the coordinate of a shield on the touch panel 101 and further diagnosing whether the coordinate detection is normal or not, the arithmetic part 104 is provided with an EEPROM for storing the reference data to be used for the self-diagnosis and by comparing the reference data with self-diagnosis data based on the reflected light, the self-diagnosis is executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a coordinate detecting device, and more particularly to an optical coordinate detecting device.

[0002]

2. Description of the Related Art At present, there is a coordinate detecting device for detecting a position on a predetermined panel surface (touch panel) touched by a finger or a pen as coordinates. Such a coordinate detection device is usually
It is connected to a device such as a computer so that an operator can input coordinates detected by the computer from the touch panel, and is also called a coordinate detection device or a coordinate input device.

A prior example of such a coordinate detecting device is disclosed in, for example, Japanese Patent Application Laid-Open No. 9-91094. According to the present invention, a light beam is irradiated on almost the entire surface of the touch panel, and the fact that the light beam is blocked by a finger or a pen is detected by not receiving the reflected light of the irradiation light. The coordinate detecting device detects the shielding position (that is, the position of a finger or a pen) as a coordinate in an arithmetic circuit. Such a coordinate detecting device is also called an optical coordinate detecting device, and is widely used because of its relatively simple configuration.

Meanwhile, in an optical coordinate detecting device, it is independently determined whether a light source and a reflecting member used for light irradiation and a light receiving device function normally and a coordinate detecting system maintains a predetermined accuracy. Some have a self-diagnosis function to judge. Diagnosis performed by such a self-diagnosis function generally takes data of reflected light irradiated in a state where nothing is touched on a touch panel into, for example, a line memory, and all the data for one line is a predetermined value. This is done by determining that a value equal to or greater than the value is normal and that at least a part of the value is equal to or less than the predetermined value is abnormal.

[0005] Data determined to be normal by the above-mentioned self-diagnosis may be used as reference data for performing shading correction. Shading correction is an optical system that irradiates and receives light, or C
This correction is performed in order to consider the characteristics of a light receiving device such as a CD in the coordinate detection process.

[0006]

However, the coordinate detecting device having the self-diagnosis function does not particularly have a configuration for prohibiting a shield from touching the touch panel during the self-diagnosis. For this reason, there is a possibility that data may be acquired in a state where a shield is present on the touch panel even during the self-diagnosis.

In such a case, the acquired data is determined to be abnormal if there is a portion below a predetermined value. But,
For example, as shown in FIG. 7, when the light is not sufficiently blocked by the blocking object and the intensity of the reflected light reduced by the blocking is equal to or higher than the normal determination value as in the part C, this data is determined to be normal and shading is performed. It is feared that it will be used for correction. In FIG. 7, the horizontal axis indicates the reflection position where the light is reflected, and the vertical axis indicates the value indicating the intensity of the reflected light received by the light receiving device, as shown in the figure. is there.

FIG. 8 is a diagram for explaining a problem when the data as shown in FIG. 7 is used for shading correction. 8, similarly to FIG. 7, the horizontal axis indicates the reflection position where the light is reflected, and the vertical axis indicates the value indicating the intensity of the reflected light received by the light receiving device. In FIG.
(A) shows shading correction data used for shading correction, (b) shows coordinate detection data acquired for coordinate detection, and (c) shows data obtained by shading-correcting the data of (b) by (a). FIG.

As shown in FIG. 8B, even if there is a portion C 'in which the light shielding can be sufficiently detected in the coordinate detection data, this is determined by using shading correction data having the portion C as shown in FIG. After the shading correction, only the difference between C and C ′ remains in the data after the shading correction as shown in (c). As a result, the portion C ″ of the data after the shading correction has a value that is equal to or greater than the occlusion determination reference value (a value that is a reference for determining that light is occluded at that position). Although the coordinates are input by touching with a pen, this input is not accepted by the coordinate input device, and the input fails.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and performs self-diagnosis and shading correction using more appropriate reference data to improve the reliability of self-diagnosis and the coordinate detection accuracy. It is an object to provide a coordinate detection device.

[0011]

The above-mentioned problems can be solved by the following means. That is, the invention according to claim 1 is an optical unit that emits light onto a touch panel surface and receives reflected light of the emitted light, and reflected light that reflects emitted light emitted from the optical unit and travels toward the optical unit. And a coordinate detecting unit that detects the coordinates of the shield on the touch panel by blocking light emitted from the optical unit and preventing the reflected light from being received by the optical unit, and coordinates by the coordinate detecting unit. A self-diagnosis unit for diagnosing whether or not the detection is normal; the self-diagnosis unit has a reference data storage unit for storing reference data used for self-diagnosis; The self-diagnosis is performed by comparing the reflected light data based on the reflected light generated in step (1).

With this configuration, the self-diagnosis unit stores the reference data used for the self-diagnosis in advance, and converts the reference data and the reflected light data based on the reflected light generated by the reflecting member. The self-diagnosis can be performed by the comparison. Therefore, the reference data is dedicated to the self-diagnosis of each coordinate detecting device, and it is easy to set the optimal reference data for the self-diagnosis of each coordinate detecting device.

The invention according to claim 2 is characterized in that the reference data storage unit can update the reference data.

With this configuration, the reference data is updated in accordance with the state of the coordinate detecting device, and the optimum reference data for the self-diagnosis of the coordinate detection is obtained regardless of the aging of the coordinate detecting device and the environment in which the coordinate detecting device is used. Can be set.

The invention according to claim 3 is characterized in that the reference data stored in the reference data storage unit is data obtained by the coordinate detecting device itself for which self-diagnosis is performed.

With this configuration, the reference data and the reflected light data to be compared in the self-diagnosis are obtained by the same coordinate detecting device. Therefore, when comparing the two, it is not necessary to consider the influence of the variation of the coordinate detection device and the difference in the characteristics.

According to a fourth aspect of the present invention, the reference data and the reflected light data are waveform data indicating a relationship between the reflection position on the reflection member and the reflection light intensity, and the self-diagnosis unit sets the reference data for all the reflection positions. The self-diagnosis is performed by comparing the reflected light intensity between the data and the reflected light data.

With this configuration, even when there is a variation in the reflected light depending on the reflection position due to the characteristics of the coordinate detecting device, the variation is not erroneously determined to be different from the reference data.

According to a fifth aspect of the present invention, the optical unit comprises:
A total of two light sources are installed at different positions on the touch panel, and each light source emits fan-shaped light substantially parallel to the touch panel surface and centered on the installation position, and receives reflected light of light emitted from the light source. It is characterized in that it is configured by integrally incorporating a light receiving unit.

With this configuration, errors and variations in the positional relationship between the light source and the light receiving section can be suppressed, and variations in the optical system of the coordinate detecting device can be reduced.

The invention according to claim 6 is characterized in that the self-diagnosis unit further includes a self-diagnosis-in-progress display means for indicating to the outside that the self-diagnosis unit is executing the self-diagnosis.

With this configuration, the coordinate detecting device is not operated during the self-diagnosis, and it is possible to prevent a shield from being placed on the touch panel during data acquisition for the self-diagnosis.

[0023]

Embodiments of the present invention will be described below. FIG. 1 is a diagram illustrating a configuration of a coordinate detection device according to the present embodiment. Optical units 102A and 102B that emit light onto the touch panel surface and receive reflected light of the emitted light are provided in the coordinate detection device according to the present embodiment.
And reflecting members 103A, 103B, 103C that reflect light emitted from the optical units 102A, 102B and generate reflected light toward the optical units 102A, 102B.
The light emitted from the optical units 102A and 102B is shielded, and the light receiving by the optical units 102A and 102B is blocked so that the coordinates of the shield on the touch panel 101 are detected and a personal computer (PC, PC in the figure) is used. ), And an interface unit 105 for exchanging data between the arithmetic unit 104 and the personal computer 108.

The coordinate detecting device shown in FIG. 1 has an outer frame 106 outside the touch panel 101 and a display member 107 provided on the outer frame 106. This display member 107
Is a self-diagnosis-in-progress display means of the present embodiment, which indicates to the outside that the coordinate detection device is performing self-diagnosis. Such a display member 107 prevents the shielding object from being placed on the touch panel 101 during the self-diagnosis by indicating that the coordinate detection device is performing the self-diagnosis around, thereby obtaining appropriate self-diagnosis data. It is to make it. In the present embodiment, the above-described display member 107 is configured to be constantly turned on, and is turned off only during the self-diagnosis. The specific operation of the display member 107 will be described later.

The arithmetic unit 104 according to the present embodiment is configured to perform a self-diagnosis as to whether or not the coordinate detection is normally performed, and data (reference data) used for the self-diagnosis.
EEPROM (Electrically Erassable Rea)
d-Only Memory) 204 (FIG. 2). Then, the reference data and the reflection members 103A, 103B,
Self-diagnosis is performed by comparing data (self-diagnosis data) generated based on the reflected light generated in 103C and used for self-diagnosis.

Of the above-described configuration, in the present embodiment,
A liquid crystal display is used for the touch panel 101.
The reflecting members 103A, 103B, and 103C are members that reflect the irradiated light recursively, and the reflected light generated here passes through the same optical axis as that at the time of emission, and is reflected by the optical unit 102.
A, 102B.

The optical units 102A and 102B
Are located at different positions on the touch panel 101 respectively.
It is installed individually. Each optical unit 102A, 102B
Have the same configuration, and the touch panel 10
A light source 1 that emits fan-shaped light substantially parallel to the light source 1 and centered on the installation position, and a light receiving unit 2 that receives reflected light of light emitted from the light source 1 are integrally incorporated.

The emitted light emitted from the light source 1 and the reflected light received by the light receiving section 2 are, for example, optical units 102A,
The light is separated by a half mirror (not shown) or the like inside 102B. The light receiving section 2 is installed at a position where only the separated reflected light can be received. In the present embodiment, a CCD (Charged Coupled Device) line sensor is used for such a light receiving unit 2.

In the coordinate detecting device configured as described above, when a shield is placed on the touch panel 101, of the light emitted from the light source 1, only the light whose optical axis passes through the position of the shield is the reflecting member 103A. , 103B, 103C cannot be reached. Light having such an optical axis is not received by the light receiving unit 2 as a matter of course. For this reason,
In the light receiving section 2 formed by a CCD line sensor, reflected light of low intensity is incident only on an element at a position where light of this optical axis should be received (or no reflected light is incident). The optical axis can be specified. By specifying the optical axes by the optical units 102A and 102B provided at two locations, the coordinates of the shield can be detected as the intersection of the two optical axes.

FIG. 2 is a block diagram for explaining the arithmetic unit 104 for executing the above coordinate detection. Arithmetic unit 10
Reference numeral 4 denotes an A / D converter 206 for A / D converting an analog signal acquired by the light receiving unit 2 of the optical units 102A and 102B into a digital signal. The A / D converter 206 processes the converted signal and outputs an image captured by the light receiving unit. An image processing LSI 205 for creating data (image data), and a line memory 20 for storing the created image data for each line of the CCD line sensor
7 are provided.

Further, the configuration of FIG.
CPU 201, ROM 202, RAM 2 for executing an operation for coordinate detection based on the image data stored in
03, an EEPROM 204. This EEPR
The OM 204 is a reference data storage unit according to the present embodiment, and stores reference data to be compared with self-diagnosis data. The operation of first storing the reference data in the EEPROM 204 is performed at the stage of assembly on the manufacturing side or adjustment before shipment. The EEPROM 204 is a rewritable storage device as is well known. Therefore, the operator can update the reference data stored in the EEPROM 204 on the manufacturing side to the data acquired by the coordinate detecting device itself.

By updating the reference data to the data obtained by the coordinate detecting device itself, the self-diagnosis data and the reference data become data obtained by the same coordinate detecting device. Therefore, there is no difference between the reference data and the self-diagnosis data due to differences in the individual devices such as variations in the optical system of the coordinate detection device and variations in characteristics, thereby further improving the reliability of the self-diagnosis and the detection accuracy of the coordinate detection device. Can be enhanced.

Further, in the coordinate detecting device, it is conceivable that a difference occurs in data obtained due to a temporal change of the optical system (such as a decrease in the light amount of the light source). Further, in the case of an optical coordinate detection device, it is conceivable that the acquired data may differ depending on the environment in which the device is used (ambient lighting conditions, indoor or outdoor).

In order to prevent such a difference in acquired data from being determined as abnormal, in the present embodiment, the reference data is rewritten periodically. Or,
When the usage environment changes, data is acquired in that environment and used as reference data. If you do this,
The reference data can always be set according to the state of the coordinate detection device, and the reliability of the self-diagnosis and the detection accuracy of the coordinate detection device can be further improved.

Next, a method for comparing the reference data with the self-diagnosis data will be specifically described with reference to FIG.
FIG. 3A is a diagram illustrating reference data A, and FIG.
FIG. 3 is a diagram illustrating self-diagnosis data B acquired by the coordinate detection device itself for self-diagnosis, and FIG. 3C is a state in which reference data A in FIG. 3A is compared with self-diagnosis data B in FIG. FIG. As shown, the reference data and the self-diagnosis data are provided on the reflecting members 103A, 103B, 10B.
This is waveform data showing the relationship between the 3C reflection position on the horizontal axis and the reflected light intensity on the vertical axis. In the arithmetic unit 104,
The self-diagnosis is performed by comparing the reflected light intensities of the reference data and the self-diagnosis data for all the reflection positions shown.

When a self-diagnosis instruction is issued from the personal computer 108, the CPU 201 first displays the display unit 107 as shown in FIG.
The light turns off as shown in (a), indicating that the coordinate detection device cannot be used. Then, the light sources 1 of the optical units 102A and 102B are turned on, and light is irradiated on the touch panel 101. The signal generated based on the reflected light is converted by the arithmetic unit 104, and the image data for one line is stored in the line memory 207 as self-diagnosis data.

The CPU 201 is connected to the EEPROM 20
4 and read out the reference data from the line memory 207.
The self-diagnosis data is also read from the
03 and a comparison is made as shown in FIG. FIG.
As shown in (c), the reference data A (indicated by a solid line) and the self-diagnosis data B (indicated by a dashed line) are different from each other in an enlarged portion in the drawing.

The CPU 201 determines whether the reference data A
And the self-diagnosis data B are compared in a unit of one to several pixels. For example, if the difference d is within ± 10% of the reference data A at the reflection position where the difference d has occurred, it is normal. If so, it is determined that there is an abnormality. When this determination is completed, as shown in FIG.
7 is lit to indicate that the self-diagnosis has been completed and the coordinate detection device can be used.

According to such a configuration, since both the reference data and the self-diagnosis data are waveform data, when detecting the difference between the two, the data based on the characteristic of the coordinate detecting device itself, such as a change in the reflected light intensity depending on the reflection position. Differences are eliminated. Therefore, such a configuration is different from the conventional method of comparing the self-diagnosis data with a certain value.
It can be said that a more reliable self-diagnosis can be performed.

According to such a configuration, the fact that the self-diagnosis is being performed is made clear to the outside, so that the operator determines whether or not the coordinate detection device is usable, and further touches the touch panel 101. It is easy to determine whether or not it is OK. Therefore, the coordinate detection device according to the present embodiment
By using data acquired in a state where a shield is present on the touch panel 101 as self-diagnosis data, it is possible to prevent the coordinate detection device from being erroneously determined to be abnormal, and to further enhance the reliability of the self-diagnosis. . Also,
By using data acquired in a state where a shield is present on the touch panel 101 as reference data, erroneous detection of coordinates caused by performing shading correction can be prevented, and the accuracy of coordinate detection can be improved.

Next, the processing of this embodiment described above will be described with reference to a flowchart as shown in FIG. FIG.
The flowchart of FIG. 4 starts when, for example, a self-diagnosis instruction is issued from the personal computer 108 to the arithmetic unit 104. In response to this instruction, the arithmetic unit 104 causes the display member 107 to be displayed.
To indicate to the outside that self-diagnosis is being performed (S
1). Subsequently, the arithmetic unit 104 loads the image data to be the self-diagnosis data into the line memory 207 (S2). Next, the captured image is compared with reference data stored in the EEPROM 204 (S3).

As a result of the comparison in step S3, it is determined whether or not the difference between the self-diagnosis data and the reference data is at or above a predetermined level (S4). If the difference is at or above the predetermined level (S4: Yes) After the error is displayed (S9), the display member 1 is displayed.
07 is turned off, and the process ends (S8). If the difference is equal to or less than the predetermined level (S4: No), an OK display indicating that the coordinate detection system is normal is displayed on, for example, the display of the personal computer 108 (S4: No). S5).

Next, the arithmetic section 104 determines whether or not to update the self-diagnosis data acquired here as reference data (S6). If not updated, the processing is terminated as it is (S6: No). On the other hand, when the reference data is updated (S6: Yes), the reference data is updated by rewriting the self-diagnosis data acquired this time (S7), after which the display member 107 is turned on and the process is terminated (S7).
8).

The determination of whether or not to update the reference data in step S6 is performed based on the contents input by the operator from this screen by displaying a screen on which the operator can select to update the reference data on the personal computer 108. You may do it.

Further, the present invention is not limited to the above-described embodiment. For example, the reference data storage section of the present invention is not limited to an EEPROM, but a storage capable of updating data. Other configurations may be used as long as they are devices. Furthermore, the touch panel of the present invention is not limited to the configuration of the display, but may have another configuration such as a whiteboard.

Further, the self-diagnosis display means of the present embodiment is not limited to the display member 107. For example, characters are displayed on a touch panel configured as a display as shown in FIG. It may be configured as described above.

[0047]

The present invention described above has the following effects. That is, according to the first aspect of the present invention, it is possible to easily set, as the reference data, data optimal for the self-diagnosis of each coordinate detecting device. Therefore, the reliability of the self-diagnosis can be further improved. Further, by performing image processing such as shading correction using such reference data, it is possible to improve the coordinate detection accuracy.

According to the second aspect of the present invention, it is possible to set the reference data in accordance with the aging of the coordinate detecting device and the environment in which the coordinate detecting device is used, thereby further improving the reliability of the self-diagnosis.

According to the third aspect of the present invention, the result of the self-diagnosis is not affected by the variation and the difference in characteristics of the coordinate detecting device, and the reliability of the self-diagnosis can be further improved.

According to the fourth aspect of the present invention, the result of the self-diagnosis is not affected by the variation of the reflected light depending on the reflection position of the coordinate detecting device, and the reliability of the self-diagnosis can be further improved.

According to the fifth aspect of the present invention, the variation of the optical system in the coordinate detecting device can be reduced, and the reliability of the self-diagnosis can be further improved.

According to the invention of claim 6, it is possible to prevent a shield from being placed on the touch panel during the data acquisition for the self-diagnosis, and to further enhance the reliability of the self-diagnosis. According to the first to sixth aspects of the present invention, there is provided a coordinate detection device capable of performing self-diagnosis and shading correction using more appropriate reference data to improve the reliability of the self-diagnosis and the coordinate detection accuracy. can do.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a coordinate detection device according to an embodiment of the present invention.

FIG. 2 is a block diagram for explaining a calculation unit shown in FIG.

FIG. 3 is a diagram illustrating a method for comparing reference data and self-diagnosis data according to an embodiment of the present invention,
(A) is a diagram illustrating reference data A, (b) is a diagram illustrating self-diagnosis data, and (c) is a diagram illustrating a state in which the reference data and self-diagnosis data are compared.

FIG. 4 is a diagram for explaining a configuration indicating that the coordinate detection device according to the embodiment of the present invention cannot be used;

FIG. 5 is a flowchart illustrating a process according to an embodiment of the present invention.

FIG. 6 is a diagram for explaining another example of the self-diagnosis display unit according to the embodiment of the present invention.

FIG. 7 is a diagram illustrating a problem at the time of self-diagnosis in a conventional coordinate detection device.

FIG. 8 is another diagram illustrating a problem at the time of self-diagnosis in the conventional coordinate detection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light source 2 Light receiving part 101 Touch panel 102A, 102B Optical unit 103A, 103B, 103C Reflecting member 104 Operation part 105 Interface part 106 Outer frame 107 Display member 108 Personal computer 201 CPU 202 ROM 203 RAM 204 EEPROM 205 Image processing LSI 206 A / D conversion Machine 207 line memory

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5B068 AA01 AA22 BB20 BC05 BE07 DD02 5B087 AA00 AC01 CC02 CC33 DJ00

Claims (6)

[Claims] 1. An optical unit that emits light onto a touch panel surface and receives reflected light of the emitted light, and reflects emitted light emitted from the optical unit to generate reflected light directed to the optical unit. A reflecting member, a light detecting unit that shields light emitted from the optical unit, and detects coordinates of a shield on the touch panel by preventing reception of reflected light by the optical unit; A self-diagnosis unit for diagnosing whether the coordinate detection is normal, the self-diagnosis unit having a reference data storage unit for storing reference data used for self-diagnosis, And performing self-diagnosis by comparing the reflected light data based on the reflected light generated by the reflecting member. 2. The coordinate detecting device according to claim 1, wherein the reference data storage unit can update the reference data. 3. The reference data stored in the reference data storage unit is data acquired by a coordinate detection device itself that performs a self-diagnosis.
3. The coordinate detecting device according to 1. 4. The reference data and the reflected light data are waveform data indicating the relationship between the reflection position on the reflection member and the reflected light intensity, and the self-diagnosis unit determines the reference data and the reflected light for all the reflection positions. The coordinate detection apparatus according to claim 1, wherein self-diagnosis is performed by comparing the reflected light intensity with data. 5. A light source, wherein two optical units are installed at different positions on the touch panel, and each emits fan-shaped light substantially parallel to the touch panel surface and centered on the installation position. The light receiving section for receiving reflected light of the light emitted from the light source is integrally incorporated and configured.
The coordinate detecting device according to any one of the above. 6. The self-diagnosis unit according to claim 1, further comprising a self-diagnosis display unit that externally indicates that the self-diagnosis unit is executing a self-diagnosis.
The coordinate detecting device according to any one of the above.