JPH06230145A - Optical detector - Google Patents

Abstract

PURPOSE:To provide an optical detector comprising at least a pair of light emitting element and a light receiving element spaced apart from each other by a predetermined distance and detecting the presence or the position of an object shading a light beam projected from the light emitting element toward the light receiving element in which erroneous detection caused by the light emitting element can be specified. CONSTITUTION:The optical detector comprises means 8 for driving a light emitting element 1, means 13 for detecting output voltage from the light emitting element 1, and means 5 for comparing a detected voltage value with a predetermined reference level, wherein the comparison results are employed for deciding whether the light emitting element 1 is driven correctly, i.e., whether the light emitting element 1 is normal or not.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical detecting device for optically detecting the position or presence / absence of an object.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 5, a plurality of pairs of a light emitting element 1 and a light receiving element 2 are arranged at a predetermined distance from each other to form a detection panel 3, and a pair of light emitting and light receiving elements are sequentially operated. There is known an optical detection device that detects the position of the object 4 on the panel 3 depending on whether or not the light emitted from each light emitting element 1 toward the corresponding light receiving element 2 is blocked by the object.

FIG. 6 shows an example of a schematic overall configuration of the above optical detection device. In FIG. 6, reference numeral 11 denotes a light emitting element array in which a plurality of light emitting elements 1 are arranged, and the light receiving element array 12 is separated from the light emitting element array 11 by a predetermined distance.
Are provided, and the light receiving elements 2 that are paired with the light emitting elements 1 are arranged therein. Microprocessor 5
Sequentially scans the light emitting element drive circuit 6 and the multiplexer 7 to enable the pair of the light emitting element 1 and the light receiving element 2 to operate.
The arithmetic control circuit 51 provided in the microprocessor 5 sequentially scans the light emitting element drive circuit 6 and the multiplexer 7 to enable the light emitting element 1 and the light receiving element 2 forming a pair. At this time, a current is supplied from the current supply circuit 8 to the light emitting element 1. A signal representing the individual light receiving amount of each light receiving element 2 obtained from the light receiving element 2 in the operable state via the multiplexer 7 is amplified by the amplifier 9, and the microprocessor 5
It is input to the arithmetic control circuit 51 via the analog / digital converter 52 provided in the. The arithmetic control circuit 51 uses the RAM provided in the microprocessor 5 for the individual light receiving amount.
The presence or absence of light shielding is determined by comparing with an individual reference value stored in the (random access memory) 53 for each pair of the light emitting element 1 and the light receiving element 2.

Further, in the optical detection device, as shown in FIG. 5, when the light-shielding object 4 is touched on the detection panel 3 (touch-on), the light-shielding object 4 touching the detection panel 3 is turned off from the detection panel 3. The operation information of the detection panel 3 indicating that the light-shielding object 4 touching the detection panel 3 has moved to another position of the detection panel 3 (touch movement) (touch-off). That is, the detection panel 3 scans the light emitting element 1 and the light receiving element 2 forming a pair, compares the touch state and the touch position of the previous light-shielding object, determines the type of touch-on or touch-off, or touch movement, and determines the touch operation. Every time there is a change, the coordinate data (the coordinate data of the moving position in the case of touch movement) along with the operation identification information indicating the type are transmitted to the host computer side only once via the communication cable. The host computer receives the operation identification information and the coordinate data, identifies the operation state of the detection panel 3, and performs the required processing.

[0005]

As shown in FIG. 6, in the conventional optical detection device, due to a defect in at least one of the light emitting element 1 and the light receiving element 2, there is light shielding although there is no light shielding by an object. There is an inconvenience that it is erroneously determined. In this case, the cause of the erroneous determination that the light is shielded depends not only on the light emitting element 1 and the light receiving element 2 but also on the device itself, which is complicated, and it is difficult to specify these causes. If it is possible to distinguish whether the cause of the erroneous determination depends on the light emitting element 1 or another cause, the cause can be specified or narrowed down.

An object of the first invention is to provide an optical detection device capable of identifying erroneous detection based on the cause of a light emitting element and preventing the erroneous detection.

Further, in the conventional optical detection device shown in FIG. 6, the individual reference value stored in the RAM 53 is the amount of light received when there is no light blocking at the start of operation of the device when the power is on, or from the host computer. The amount of light received without shading when a command for storing a reference value is given is used as a reference. Therefore, when there is no command for storing the reference value from the host computer, the individual reference value is not adjusted, and the presence or absence of light shielding is determined based on the individual reference value from before. By the way, the cause of erroneous determination of whether or not the object is shielded from light is deterioration of the light emitting element 1 and the light receiving element 2 itself and failure, temperature, dust accumulated between the light emitting element 1 and the light receiving element 2, influence of ambient light. It is possible that the mechanical part of the device is changed and the transmittance of the infrared filter is lowered. For this reason, the amount of light received when there is no light shielding fluctuates over time, and if the presence or absence of light shielding is judged based on the individual reference value that has been used before, the individual reference value will be linked to the time variation. There is a risk of erroneous detection.

The second object of the present invention is to automatically adjust the individual reference value of the amount of received light, which serves as a reference for determining the presence or absence of light shielding, in response to the change over time in the amount of received light, thereby preventing erroneous detection. It is an object of the present invention to provide an optical detection device which is prevented.

The operation identification information transmitted from the detection panel 3 to the host computer side via the communication cable is transmitted only once every time a touch-on operation, a touch-off operation, or a touch movement operation is performed. This operation identification information is a binary logic "0" signal when touch-on, a binary logic "1" signal when touch-off, and a binary logic "1" signal when touch-moving.
The value logic "2" signal is transmitted. Therefore, when a transfer error of the operation identification information occurs and a data loss occurs, the host computer cannot obtain accurate information about the object 4 on the detection panel 3 and also the reception order of the operation identification information. There is a possibility that a logical contradiction may occur and an abnormal operation may occur. For example, the operation identification information is “2”
(Touch movement), “1” (touch off), and “0” (touch on) are transferred in this order, and when the operation identification information of “1” indicating touch off is missing, “2” is followed by “ However, the host computer cannot identify the information even though the touch-off occurs and the cursor display indicating the touch-on continues on the screen of the detection panel 3. is there. When the operation identification information is transferred in the order of “0”, “1”, and “0”, and the operation identification information of “1” is missing, the operation identification information indicating touch-on is set to “0”,
Since "0" is received twice in succession, there is a possibility that an abnormal operation may occur due to a logical contradiction that touch-on is received twice in succession.

On the host computer side, when a reception error occurs and a logical contradiction occurs, there is a method of temporarily stopping the operation of the detection panel 3 and restarting it. However, since it is inconvenient to restart each time a reception error occurs, the coordinate data sent together with the operation identification information in which the reception error has occurred is discarded and the reception is continued. However, if a logical contradiction occurs on the host computer side, simply performing the process of discarding the coordinate data causes a problem that the coordinate data to be identified at present cannot be identified, which causes a malfunction. Measures were desired.

An object of the third and fourth inventions is to provide an optical detecting device which prevents the occurrence of a logical contradiction due to a data loss during data transmission, thereby preventing a malfunction.

[0012]

The optical detecting device according to the first aspect of the present invention comprises a light emission drive means for driving the light emitting element,
The light emitting device includes a voltage detecting means for detecting an output voltage and a comparing means for comparing the detected voltage value with a predetermined reference level.

The optical detecting device of the second invention is
Light emitting drive means for driving each light emitting element to emit light, measuring means for measuring each individual light receiving amount received by each corresponding light receiving element during driving of each light emitting element, and each light receiving element when there is no light shielding Storage means for storing the individual received light amount as an individual reference value, and light-shielding determination means for determining the presence or absence of light-shielding from the stored individual reference value and the current individual received light amount,
Only when it is determined that there is no light shielding, the individual reference value and an updating unit that updates the individual reference value based on the current individual light receiving amount are provided, and whether or not light is shielded each time the light emitting element is driven. It is characterized in that the individual reference value is updated only when both judgments are made and it is judged that there is no light blocking.

The optical detecting device according to the third invention is
The operation identification information and the coordinate data transmitted when the light-shielding object is touched off are continuously transmitted a plurality of times.

The optical detecting device of the fourth invention is
In the case where there is a logical contradiction in the reception order of the operation identification information received on the host computer side, there is provided information conversion means for converting the inconsistent operation identification information into operation identification information of a kind that does not logically conflict and receiving the operation identification information. It is configured.

[0016]

According to the first aspect of the present invention, the light emitting element is provided with the voltage detecting means for detecting the output voltage of the light emitting element which is driven to emit light, and the value of the detected voltage is compared with a predetermined reference level so that the light emitting element is correctly driven. It is possible to judge whether or not there is a failure of the light emitting element.

Further, according to the second aspect of the present invention, the presence or absence of light shielding is determined every time each light emitting element is driven, and the individual reference value is automatically updated only when it is determined that there is no light shielding. It is possible to always maintain an appropriate individual reference value in response to changes over time due to various causes of the amount of received light, and thus prevent erroneous detection from occurring.

Further, according to the third aspect of the present invention, since the operation identification information and the coordinate data transmitted to the host computer side at the time of touch-off are continuously transmitted a plurality of times, data loss of the operation identification information occurs during transmission. However, since the operation identification information is always received by the host computer side, a logical contradiction due to missing data of the touch-off operation identification information can be avoided.

Further, according to the fourth aspect of the present invention, when a logical contradiction occurs in the operation identification information received on the host computer side, the contradictory operation identification information is converted into consistent operation identification information. Since the host computer has a function of receiving the coordinate data and the coordinate data transmitted together with the operation identification information is received without being discarded, a malfunction is prevented.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic overall configuration diagram showing an embodiment of the first invention. The same parts as those in FIG. The current supplied from the current supply circuit 8 to each light emitting element 1 of the light emitting element array 11 is detected by the voltage detection circuit 13 as an output voltage from each light emitting element 1. The voltage detection circuit 13 is composed of, for example, a comparator, the voltage value detected here is compared with a predetermined reference level, and the comparison result is given to the microprocessor 5 as a signal indicating whether the light emitting element 1 is good or bad. .

FIG. 2 is a diagram for explaining a main circuit configuration having a function of detecting a failure of the light emitting element of the first invention. In FIG. 2, detection of the presence / absence of a failure of one light emitting element 1 in the light emitting element array 11 is illustrated, and the same configuration is applied to each light emitting element 1. A transistor 1 is provided at the anode of the light emitting element 1 which is a light emitting diode
4 is connected to the emitter, and the cathode of the light emitting element 1 is connected to the collector of the transistor 15.
A resistor 16 is connected to the emitter of 5. Transistor 14, light emitting element 1, transistor 15 and resistor 1
6 are connected in series. The light emitting element drive circuit 6 shown in FIG. 1 outputs a selection signal for selecting one of the light emitting elements 1 of the light emitting element array 11 to the base of the transistor 14. The current supply circuit 8 is composed of a digital / analog (D / A) converter 17 and an amplifier 18 in this example. The current supply circuit 8 converts a digital signal sent from the microprocessor 5 into an analog signal and inputs the analog signal into the amplifier 18. Is supplied to the base of the transistor 15. The light emitting element 1 is driven to emit light only while current is being supplied to both bases of the transistors 14 and 15, and
A voltage is generated in the resistor 16, and this voltage is detected by the voltage detection circuit 13
Given to. The voltage detection circuit 13 functions as a comparator in this example, the voltage generated in the resistor 16 is compared with a predetermined reference voltage, and when the voltage is higher than the reference voltage, there is voltage detection, that is, a signal indicating that there is no abnormality in the light emitting element 1. However, when the voltage is lower than the reference voltage, no voltage is detected, that is, a signal indicating an abnormality of the light emitting element 1 is output to the microprocessor 5. Based on the input detection signal, the microprocessor 5 determines whether or not there is an abnormality in the light emitting element 1 that is currently driven to emit light, and if an abnormality occurs, displays the abnormality of the corresponding light emitting element 1. .

In place of the voltage detection circuit 13, A
A / D converter may be connected to convert the voltage value of the resistor 16 into a digital signal and input the digital signal to the microprocessor 5. In this case, the microprocessor 5 compares the stored reference value with the input signal to determine whether the light emitting element 1 is abnormal. In this configuration, since the input detection signal can be monitored by the microprocessor 5 and the change with time from the initial value of each light emitting element 1 can be known, the replacement time of each light emitting element 1 can be known before the failure. It is possible to prevent the occurrence of defects in advance.

FIG. 3 is a flow chart for explaining the operation of the second invention. As the schematic system configuration diagram of the second invention, the schematic overall configuration diagram shown in FIG. 6 can be used. Therefore, FIG. 3 will be described with reference to FIG. As described above with reference to FIG. 6, the arithmetic control circuit 51 compares the current individual light receiving amount with the individual reference value for each light receiving element 2 stored in the RAM 53 to determine the presence or absence of light shielding. The arithmetic control circuit 51 is provided with a counter C, a compensation register P and the like necessary for carrying out the second invention.
In the second aspect of the invention, when the arithmetic control circuit 51 determines that there is light shielding, the current individual reference value is maintained and used as a reference value for the next determination, but when it is determined that there is no light shielding, the individual individual reference value is used. The reference value is corrected (updated) according to a predetermined procedure shown in FIG. This operation is performed by each pair of light emitting elements 1.
And every time the light receiving element 2 is scanned, and for each pair of light emitting and light receiving elements.

When the power source of the optical detecting device is turned on, each time the pair of the light emitting element 1 and the light receiving element 2 is scanned,
The flow shown in FIG. 3 is executed. First, in step S1, the scanning number counter C of the microprocessor 5 is cleared and C = 0 is stored. Next, in step S2, the arithmetic control circuit 51 determines that the light receiving element 2 currently being scanned.
The individual received light amount P (c) received by
Store in M53. Next, in step S3, it is determined whether the content of the scanning number counter C is 1 or more,
If it is determined to be No, the process proceeds to step S4. Step S4
In the above, the individual received light amount P (c) received for the first time after the power is turned on and the scanning is started is the individual reference value Po (c).
Is stored in the RAM 53.

If YES is determined in step S3, the process proceeds to step S5, in which the individual reference value Po is set.
Specific received light amount b indicating the ratio between (c) and the individual received light amount P (c)
(C) = P (c) / Po (c) is calculated and stored in the RAM 53. Next, the process proceeds to step S6, and the specific received light amount b (c)
Is greater than a predetermined shading reference value q,
If it is determined to be No, the process proceeds to step S7. Step S7
When the specific light receiving amount b (c) is equal to or less than the light blocking reference value q, it is determined that the light receiving amount is significantly reduced and light is blocked by the object. If YES is determined in step S6, the process proceeds to step S8, where it is considered that there is no light blocking, and the process proceeds to step S9. In step S9, whether the individual reference value Po (c) is larger than the individual light receiving amount P (c),
That is, it is determined whether or not the individual light receiving amount P (c) is increased or decreased during one scanning period, and if it is determined to be “NO”, step S
If the answer is YES in step 11, the process proceeds to step S10. In step S10, it is determined that the individual light receiving amount P (c) of this time is smaller than the individual reference value Po (c), and the compensation value P1 for compensating the individual reference value is stored in the compensation register P as P = P1. To be done. In step S11, the individual received light amount P (c) of this time is the individual reference value P
The compensation value P2 for compensating the individual reference value is determined to be greater than o (c), and is stored in the compensation register P as P = P2. The compensation coefficients P1 and P2 compensate for variations in the amount of light received during one scanning period due to causes other than light shielding.
There is a relationship of (1 / P1) <(1 / P2). The reason for this is usually limited to a specific reason such as an increase in the light emission amount due to removal of dust adhering to the light emitting element when the individual light reception amount P (c) increases. It takes a large amount. Step S10 or S11
After that, the process proceeds to step S12, where the individual reference value P
The compensation of o (c) is performed. That is, the compensation register P
A new individual reference value Po (c) is calculated by the equation (1) from the compensation value P1 or P2 (= P), the individual light receiving amount P (c) and the individual reference value Po (c) stored in Is stored in the RAM 53 as the individual reference value of.

## EQU1 ## Po (c) = Po (c) + {P (c) -Po (c)} / P (1) After execution of steps S4, S7 and S12, the process proceeds to step S13 and the counter C is reached. Content of 1
The light emitting element 1 and the light receiving element 2 that are currently scanned are incremented by one, the judgment of the presence or absence of light shielding and the updating operation of the individual reference value are ended, and the process returns to step S2.

As a result of the flow shown in FIG. 3 being executed in the pair of the light emitting element 1 and the light receiving element 2 which is currently being scanned, steps S1 and S2 to S2 in the first scanning when the power is turned on.
S4 and S13 are sequentially executed to set the initial individual reference value Po.
(C) is stored. Each time after the next scanning, if there is light blocking by the object at each scanning, steps S2 to S7, S13
As a result, the individual reference value is not compensated and the current individual reference value is maintained and used in the next scan. If there is no light blocking by the object, step S2
~ S6, S8, S9, S10 (or S11), S1
As a result of sequentially performing 2 and S13, the individual reference value is automatically updated to an appropriate value.

Next, the third invention will be described. In the third invention, as shown in FIG.
It is divided into the detection panel 3 side and the host computer 21 side, and data is exchanged between the detection panel 3 and the host computer 21 via the communication cable 20. The detection panel 3 has the configuration shown in FIGS. 5 and 6 and described with reference to the drawings. The arithmetic control circuit 51 of the microcomputer 5 provided in the detection panel 3 is provided with the light shielding object 4 for the light emitted from the light emitting element 1 toward the light receiving element 2.
Each time any one of touch-on / touch-off / touch movement is performed, corresponding operation identification information “0”, “1”, “2” indicating the type of the operation is transmitted to the host computer 21 together with the corresponding coordinate data. To do. The third aspect of the present invention is different from the conventional one, in the case where the arithmetic control circuit 51 detects a touch-off of the light-shielding object 4, a plurality of pieces of operation identification information "1" indicating the touch-off are displayed together with coordinate data indicating the touch-off position. It is to transmit to the host computer 21 continuously. The operation identification information "1" and the number of times the coordinates are continuously transmitted may be output a specific number of times, and the next touch-on is identified by the arithmetic control circuit 51 and the operation identification information "0" is output. You can continue sending until. The operation identification information "1" and "2" indicating touch-on and touch movement other than touch-off and corresponding coordinate data are output only once as in the conventional case. The reason for this is that if data is missing from the touch-off operation identification information, there is a time interval until the next touch-on, and malfunctions are more easily overlooked compared to other operation identification information. This is because the operator is expected to notice the abnormality and perform the operation again even if the operation identification information lacks data.

The operation control circuit 51 configured as described above.
A case where the conventional host computer 21 receives the operation identification information output from the above will be described. Now, operation identification information “0”, “1”, ..., “1”, “0” indicating touch-on, touch-off, and touch-on are sequentially transmitted from the arithmetic control circuit 51 to the host computer 21 together with the corresponding coordinate data. . When data is lost during transmission and the operation identification information "1" sent first is not correctly received, the host computer 21 is not correctly received (logical contradiction has occurred) and the corresponding operation identification information. Discard the coordinate data. Subsequently, since the host computer 21 receives the operation identification information "1",
Receiving the information as correct (logically consistent) information,
The corresponding coordinate data is stored as touch-off coordinate data. Subsequently, although the operation identification information “1” and the corresponding coordinate data are sequentially received, a logical contradiction (touch-off is not continuously received) occurs, and hence the subsequent “1” and the corresponding coordinate data are discarded. To be done. After that, when the operation identification information "0" indicating the touch-on is received, the host computer 21 stores the corresponding coordinate data as information that does not cause a logical contradiction. As described above, even if a data loss occurs during the transmission of the operation identification information “1” indicating touch-off, the host computer 21 can always identify the touch-off and the coordinate data thereof, so that the malfunction due to the touch-off can be avoided. . Further, unlike the prior art, when touch-on operation identification information is transmitted after a touch-off data loss, a logical contradiction occurs in touch-on information and data is not discarded.

According to the fourth aspect of the present invention, as shown in FIG. 4, when there is a logical contradiction in the operation identification information transmitted from the detection panel 3 on the host computer 21 side, the logically contradictory operation identification information is displayed. A conversion unit 22 having an operation identification information conversion function of converting the operation identification information into logically consistent information and receiving the coordinate data without conversion is provided. The conversion unit 22 converts the operation identification information received according to the following program. The conversion program is stored in the conversion unit 22 as a driver program and is a part of the basic software provided by the manufacturer to the user.

The arithmetic control circuit 51 of the detection panel 3 sends an activation command indicating activation to the host computer 21 when the power source is activated. When the conversion unit 22 receives the activation command,
The following conversion processing is performed on the operation identification information that is received first immediately after receiving the activation command. That is, (a) when the operation identification information “0” indicating touch-on is received, no logical contradiction occurs, and therefore the operation identification information “0” is received without conversion. (B) When the operation identification information "1" indicating touch-off is received, the first operation after activation cannot be touch-off, and a logical contradiction occurs. Therefore, the operation identification information "1" and coordinate data are generated. Discard. (C) When the operation identification information “2” indicating the touch movement is received, since there is no touch movement at the beginning after activation, a logical contradiction occurs. Therefore, “2” indicating the touch movement is indicated as touch-on. It is converted to "1" to eliminate logical contradiction, and the corresponding coordinate data is received as coordinate data indicating touch-on. In this way, even if operation identification information that causes a logical contradiction due to missing data or the like is received as the operation identification information that is first received at the time of startup, it can be converted into operation identification information that does not have a contradiction and can be received.

The conversion unit 22 performs the following conversion processing on the operation identification information received after the second power-on operation.
(D) When operation identification information "0" indicating touch-on is received subsequently to operation identification information "0" indicating touch-on, a logical contradiction occurs, so "0" is changed to operation identification information "2" indicating touch movement. It is converted and received together with the corresponding coordinate data. Note that operation identification information “1” indicating touch-off or operation identification information “2” indicating touch movement is displayed following “0”.
When it receives, the logical contradiction does not occur, and therefore it is received as it is without being discarded and converted. (E) When the operation identification information “1” indicating touch-off is received and then the operation identification information “0” indicating touch-on is received, it is received without discarding and conversion because no logical contradiction occurs. When the operation identification information "1" is received after the operation identification information "1", a logical contradiction occurs, so "1" and the corresponding coordinate data are discarded. If the operation identification information "2" is received after the operation identification information "1", a logical contradiction occurs. Therefore, "2" indicating touch movement is converted into "0" indicating touch-on and received together with the corresponding coordinate data. To do. (F) When the operation identification information "2" indicating touch movement is received and subsequently the operation identification information "0" indicating touch-on is received, a logical contradiction occurs. Therefore, "0" is converted to "2" and the touch movement information is converted. To receive as. If the operation identification information "1" or "2" is received after the operation identification information "2", no logical contradiction occurs and the operation identification information is received as it is.

As described above, in the conversion section 22 of the host computer 21, when the operation identification information transmitted from the detection panel 3 side causes a logical contradiction for some reason, the coordinate data in which the logical contradiction occurs is converted into the conventional coordinate data. As described above, the operation identification information, which can be processed not only by discarding all but logically consistent, is converted into appropriate operation identification information and received with the coordinate data.

In the above description, the third invention and the fourth invention are described.
Although the invention is described as a separate invention from the above invention, if the optical detection device including the detection panel using the third invention and the host computer having the fourth invention is used, the operation identification information data is missing. It is possible to more appropriately deal with a reception error due to, for example, and the operator is assured of proper operation without being bothered by the problem of data loss.

[0034]

According to the first aspect of the present invention, since the voltage detecting means for detecting the output voltage of the light emitting element is provided, when a malfunction occurs in the device, it is determined whether or not the cause of the malfunction is a failure of the light emitting element. When the light emitting element is used, the cause of malfunction such as replacement of the corresponding light emitting element can be promptly removed. Further, even when there is a cause of malfunction other than the light emitting element, at least the light emitting element is removed from the cause, so that the number of labors for investigating the cause is saved, and the maintenance becomes easy. Furthermore, if the configuration is such that the detection voltage from the light emitting element is converted into a digital signal and processed by a microprocessor, the change over time of the light emitting element can be monitored, so that the degree of deterioration over time can be known and the replacement time can be judged before failure. There is an advantage that can be.

According to the second aspect of the present invention, each time the light emitting element and the light receiving element forming a pair are scanned, the individual reference value is automatically set according to the individual light receiving amount which is currently received only when there is no light blocking by the object. Properly compensated. Therefore, it is necessary to constantly maintain an appropriate individual reference value corresponding to the time-dependent variation of the individual light receiving amount due to various causes such as deterioration of the light emitting element and the light receiving element, adhesion of dust, change of ambient light, fluctuation of the device itself, temperature change, etc. Since preparation can be made, erroneous detection does not occur in the determination of the presence or absence of an object. Furthermore, the life of the device and of the device itself can be maximized.

According to the third aspect of the present invention, since the operation identification information indicating the touch-off and the coordinate data are continuously transmitted to the host computer side a plurality of times, the host computer side touch-off the touch panel and the coordinate data thereof. Can be surely identified and grasped. Moreover,
It is possible to solve the problem of the conventional abnormal operation in which the touch-on operation identification information and the coordinate data received continuously due to the lack of the touch-off operation identification information data are continuously discarded.

According to the fourth aspect of the invention, even if there is a logical contradiction in the reception order of the operation identification information transmitted from the detection panel side on the host computer side, the information for converting into the operation identification information which does not cause the logical contradiction. Since it has a conversion function, it can grasp the operation of the detection panel more accurately than the conventional configuration that simply discards information when a logical contradiction occurs, and the transmission data continues to be discarded. It is possible to eliminate the possibility that such abnormal operation will occur.

[Brief description of drawings]

FIG. 1 is a schematic overall configuration diagram showing an embodiment of the first invention.

FIG. 2 is a main circuit configuration diagram of FIG. 1 related to the first invention.

FIG. 3 is a flow chart for explaining the second invention.

FIG. 4 is a schematic configuration diagram for explaining the third and fourth inventions.

FIG. 5 is a schematic plan view of a detection panel that detects the position of a light-shielding object.

FIG. 6 is a schematic overall configuration diagram illustrating a position detecting operation of a light shielding object.

[Explanation of symbols]

 1 Light emitting element 2 Light receiving element 3 Detection panel 4 Object 5 Microprocessor 8 Current supply circuit 13 Voltage detection circuit 21 Host computer 22 Converter 51 Operation control circuit 53 RAM

Claims (4)

[Claims] 1. An optical device for arranging at least a pair of a light emitting element and a light receiving element with a predetermined distance therebetween, and detecting the position or presence or absence of an object that shields the light emitted from the light emitting element toward the light receiving element. In the detection device, an optical device comprising a light emission drive means for driving the light emitting element, a voltage detection means for detecting an output of the light emitting element, and a comparison means for comparing the detected voltage value with a predetermined reference level. Detection device. 2. An optical system in which at least a pair of a light emitting element and a light receiving element are arranged at a predetermined distance from each other and which detects the position or presence or absence of an object that shields the light emitted from the light emitting element toward the light receiving element. In the detection device, a light emission drive means for driving each light emitting element to emit light, a measurement means for measuring each individual light receiving amount received by each corresponding light receiving element during driving of each light emitting element, and a case where there is no light shielding Storage means for storing the individual light receiving amount of each of the light receiving elements as an individual reference value, a light shielding determining means for determining the presence or absence of light shielding based on the stored individual reference value and the current individual light receiving amount, and it is determined that there is no light shielding. Only when the individual reference value and the updating means for updating the individual reference value based on the current individual received light amount, the presence or absence of light shielding is determined every time each of the light emitting elements is driven. Both Optical detection device, characterized in that the updating of individual reference value is performed when it is determined that no light-shielding. 3. A touch-on / touch-off / movement of a touch position of a light-shielding object for light emitted from the light-emitting element toward the light-receiving element, wherein at least a pair of the light-emitting element and the light-receiving element are arranged at a predetermined distance from each other. In an optical detection device that transmits operation identification information indicating the type of operation to the host computer side together with coordinate data every time any operation is performed, the operation identification information and the coordinate data transmitted when the light-shielding object is touched off are stored. An optical detection device characterized in that it transmits a plurality of times continuously. 4. A touch-on / touch-off / movement of a touch position of a light-shielding object for light emitted from the light-emitting element toward the light-receiving element, wherein at least a pair of the light-emitting element and the light-receiving element are arranged at a predetermined distance from each other. In an optical detection device that transmits operation identification information indicating the type of the operation together with coordinate data to the host computer side every time any operation is performed, in the reception order of the operation identification information received on the host computer side. An optical detection device comprising information conversion means for converting the contradictory operation identification information into operation identification information of a type not logically contradictory and receiving when the logical contradiction occurs.