JPH045717A - Touch operation detecting device for touch panel - Google Patents

Abstract

PURPOSE:To prolong the life of a light emitting diode, and to prolong the life of a touch panel itself by switching a lighting cycle by adjusting it into two stages of short and long cycles when a light emitting element to detect a touch operated spot is periodically lighted. CONSTITUTION:In a touch operation detecting device, two kinds, at least, of the cycles of the short cycle and the long cycle and prepared for executing touch operated spot detecting operation in the touch panel. Usually, the short cycle is set in a cycle setting means 72, and the touch operated spot detecting operation is executed. When touch operation is not executed extending over prescribed time based on the count value of a first counter 75, the cycle is switched to the long cycle by a cycle changing means 73, and the lighting time of the light emitting diode 2 is shortened so that the life of the diode 2 is prolonged. Besides, this device is provided with a second counter 76 to count the total lighting time of the diode 2, and when the count value of this counter becomes over a prescribed value, an alarm is issued to an operator, and the operator is informed of the exchanging time of the touch panel.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a touch operation detection device for a touch panel, and in particular, a touch panel suitable for use in an operator's console, etc., and capable of two-dimensionally identifying touch operations. The present invention relates to a touch operation detection device.

[Conventional technology]

Conventionally, touch panels generally have a rectangular front shape, and the front portion of the touch panel has an operation area in which a large number of operation partitions are arranged in a grid pattern. The contents of the operation are displayed on each of the operation sections, and the operator can press the appropriate operation section as necessary to give a necessary command. Such a touch panel is used, for example, as an operation panel such as an operator's console for plant control.

In the operation area of the touch panel, the device configuration for recognizing which section of the touch panel is pressed is, for example, two adjacent sides of a rectangular touch panel, that is, a short side and a long side. A plurality of light emitting diodes are disposed at predetermined short intervals on each of the two sides, and a plurality of light receiving elements are disposed on the side opposite to each side so as to correspond to each light emitting diode. The configured configuration will be used. Therefore, a plurality of sets of light emitting diodes and light receiving elements are arranged.

As described above, in order to two-dimensionally recognize a touch operation location in a rectangular operation area of a touch panel, the following procedure has conventionally been performed.

A control device that controls the operation of the touch panel uses a demultiplexer to select and light one of the plurality of light emitting diodes, and at the same time uses a multiplexer to select a light receiving element corresponding to the lighted light emitting diode. Input the output signal and check the received light level. By sequentially operating all the light emitting diodes to emit light in a predetermined order, the light reception level is checked for all the light emitting diode and light receiving element pairs. If a touch operation is performed at any location, there will be an obstacle on the line connecting the light emitting diode and light receiving element corresponding to that operation location, so the light from the light emitting diode will be blocked. , the light receiving level of the light receiving element becomes lower than the reference value. By collecting data in which the received light level is lower than the reference value, the control device can know the location where the touch panel was operated as a two-dimensional coordinate position, and if the location of the operation can be known, A command corresponding to the operation location can be retrieved from data stored in the memory in advance. The light reception level detection procedure for all the light emitting diodes and light receiving elements, which is performed to detect the touch operation location on the touch panel, is performed at regular intervals, for example, every 50 m5. In this case, the lighting time of one light emitting diode is set to 1 ms or less.

In this way, for example, a plurality of light emitting diodes in the vertical direction are sequentially emitted and scanned, and then a plurality of light emitting diodes in the horizontal direction are sequentially emitted and scanned, thereby detecting an operation location in a rectangular area on the touch panel. becomes possible.

As a touch panel having the above-mentioned method of detecting a touch operation point, for example, Japanese Patent Application Laid-open No. 17826/1983,
There is one disclosed in Japanese Unexamined Patent Publication No. 167024/1983.

[Problem to be solved by the invention]

Generally, a light emitting diode has a lifespan, and this lifespan is determined by the integral value of the lighting time.

In the conventional touch panel device configuration and control method for detecting operation points described above, the light emitting diodes are always turned on at a constant cycle regardless of the frequency of touch operations, and the lifespan of the light emitting diodes is limited. was not considered at all. Therefore, the lifespan of the touch panel itself is determined by the lifespan of the light emitting diode. Since the lifespan of a light emitting diode is relatively short, about 8,000 hours, the lifespan of the touch panel itself is shortened, and the touch panel must be replaced periodically after about a year. Therefore, maintainability was extremely poor.

The purpose of the present invention is to extend the life of the light emitting diode by improving the control method of the lighting operation of the light emitting diode, extend the life of the touch panel, and to issue a warning to the operator when the life of the light emitting diode reaches the end. An object of the present invention is to provide a touch operation detection device for a touch panel.

[Means to solve the problem]

The touch operation detection device for a touch panel according to the present invention has a plurality of light emitting elements disposed on two adjacent sides of a rectangular area for operation, and a light emitting element on other two adjacent sides of the rectangular area in a one-to-one relationship. a plurality of light receiving elements arranged in a corresponding relationship,
A touch operation point detection operation is performed at a predetermined cycle in which one of the light emitting elements is selected and sequentially emitted light, and the detection signal of the light receiving element corresponding to the emitted light emitting element is read, and the received light level is detected to determine the touch operation point. A touch operation detection device for a touch panel comprising:
The control means has at least a short period and a long period regarding the period for detecting a touch operation point, and includes a period setting means that basically sets the short period, and determines whether or not a touch operation has been performed based on a detection signal of the light receiving element. a determining means for determining that there is no touch operation; a counting means for counting the time during which the determining means determines that there is no touch operation; and a period changing means for setting a long period by a period setting means when the count value of the counting means exceeds a predetermined value. It has as a feature point that it has.

In the touch panel touch operation detection device according to the present invention, in the above configuration, an alarm means for issuing an alarm to the operator is provided, and the control means includes another counting means for counting the lighting time of the light emitting element, and another counting means for counting the lighting time of the light emitting element. A feature of the present invention is that it includes a driving means that causes the alarm means to perform an alarm operation when the count value of the means exceeds a predetermined value.

[Effect]

In the touch operation detection device for a touch panel according to the present invention,
At least two types of cycles, a short cycle and a long cycle, are prepared for the cycle for executing the touch operation point detection operation on the touch panel, and the short cycle is usually set in the cycle setting means to execute the touch operation point detection operation, When a touch operation is not performed for a predetermined time or longer based on the count value of the first counting means, the period changing means switches the period to a long period, shortens the lighting time of the light emitting element, and lengthens the life of the light emitting element.

Further, the touch operation detection device for a touch panel according to the present invention is configured to include a second counting means for counting the total lighting time of the light emitting elements, and to issue a warning to the operator when this count value exceeds a predetermined value, This notifies the operator when it is time to replace the touch panel.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 schematically shows the configuration of a device for detecting a touch operation location on a touch panel. A rectangular area 1 indicates a rectangular area where a touch operation is performed, which is located almost in front of the touch panel. For example, 25 light emitting diodes (also referred to as LEDs in the following description and drawings) 2 are arranged at predetermined intervals on the left vertical short side of the region 1.
They are arranged in rows, and there are, for example, 40
The light emitting diodes 2 are arranged in one row at the same predetermined intervals as described above. Further, a plurality of light receiving elements 3 are arranged in a row on the right short side and the upper long side, which are opposite to the left short side and the lower long side, respectively. Each light receiving element 3 is
It is arranged opposite to the corresponding light emitting diode 2. The operation area 1 includes the light emitting diodes 2 arranged vertically and horizontally.
Based on the light conduction relationship between the light-receiving element 3 and the light-receiving element 3, it is substantially partitioned into a plurality of grid-shaped sections 1a, and assuming that the horizontal direction is the X axis and the vertical direction is the y axis, for each section (x, Coordinates can be defined in the form y).

These coordinates are given by (1, 1) to (25, 40) for each section 1a from the upper left to the lower right. As is clear from these coordinates, the light emitting diode 2 and the light receiving element 3 generate 1000 (
= 25x40) operation points can be identified.

In the arrangement state of the light-emitting diodes 2 and light-receiving elements 3 described above, when any one of the plurality of light-emitting diodes 2 is turned on, the light travels straight toward the corresponding light-receiving element arranged on the opposite side, and As long as there is no obstacle on the light path, the light is received by the light receiving element. In addition, when the touch panel operation part on the path of the light is operated and an obstacle is formed, the light is dispersed.
Light at a predetermined level no longer reaches the corresponding light receiving element. Therefore, by finding a light receiving element whose light receiving level is below a predetermined level among the vertical and horizontal light receiving elements, it is possible to know by coordinates which location in the operation area 1 of the touch panel has been operated. In this way, the touch operation location on the touch panel can be identified based on the relationship between light conduction and non-conduction between the light emitting diode and the light receiving element.

FIG. 2 shows an electric circuit section of a touch operation detection device that operates the plurality of light emitting diodes and light receiving elements. Second
In the figure, 6 is a control section formed by a microcomputer, and the control section 6 has an arithmetic section and a memory inside.

The memory stores a program for lighting each light emitting diode in a predetermined order, a program for reading light reception levels from each light receiving element in a predetermined order, a program for performing predetermined calculations on input data, etc. ing. Note that the read data is stored in the memory. In order to operate the light emitting diode 2 and light receiving element 3, the control section 6 outputs a selection command instructing which light emitting diode is to be turned on and from which light receiving element its detection signal is to be read. A selection command regarding the light emitting diode 2 is given to the demultiplexer 7, and the demultiplexer 7 selects any one of the plurality of light emitting diodes based on the selection command, and supplies power from the battery 9 to it to operate the light emitting diode. .

Further, a selection command regarding the light receiving element 3 is given to the multiplexer 4, and the multiplexer 4 is controlled to read the output signal of one light receiving element corresponding to the selected light emitting diode. The output signal of the selected light receiving element passes through the multiplexer 4, is converted into a digital value by the A/D converter 5, and is input to the control section 6. Therefore, by checking the light reception level of the light receiving element between the selected light emitting diode and the light receiving element, it is possible to know whether there is an obstacle, that is, a touch operation, in the light path. Reference numeral 8 denotes an alarm lamp connected to the control unit 6, and under required conditions, the control unit 6 provides a drive signal to the alarm lamp 8 to issue an alarm to the operator.

Next, the procedure of the lighting operation of the light emitting diode 2 and the operation of reading the detection signal of the light receiving element, which are executed by the control section 6, will be explained according to the flowcharts shown in FIGS. 3A and 3B. The flowcharts of FIG. 3A and FIG. 3B are connected by connection terminals ■ and ■.

The lighting operation of the light emitting diode and the operation of reading the output of the light receiving element according to this flowchart are started periodically. Regarding the period, in this embodiment, for example, two types of period T
. and T1 are prepared, and the activation period is set according to each condition as described later. Period T. and T1, the relationship is set, for example, as T1'' 5 T o.

Period T. is the basic short period, while the period T1
is a long cycle that is set when no touch operation on the touch panel is performed for a predetermined period of time or more.

To is set to, for example, 50 m5 as shown in FIG. 4, and a total of 65 light emitting diodes 2 in the vertical and horizontal directions are
During basic operation, each lighting period is T. The light is turned on for a period of Δt. However, the light emitting diode 2 is NO,
In order to operate sequentially from 1 to N0.65, the lighting time Δ
The lighting time of the pulse for setting t is set by shifting each light emitting diode. Each of the 65 light emitting diodes is operated once during the lighting period of 5 Qms.

Lighting period T. Immediately after completion of the period T for the next lighting operation. is started. Therefore, when looking at the operation of each light emitting diode, the lighting operation is performed at a period of To. When the period changes to T, the lighting time and lighting time of each light emitting diode do not change in principle, so the first T in the period T. When all the light emitting diodes are lit at , they are not lit during the remaining 4To. Therefore, when the lighting period is changed to 11, the lighting time of each light emitting diode is reduced to 1/4.

In the flowchart of FIG. 3A, steps 20 to 2
The process 200 consisting of 5 detects a touch operation by lighting up 25 light emitting diodes arranged vertically in FIG. 1 and reading the detection signal from the corresponding light receiving element arranged vertically. This is a process that performs In step 20, a variable n for counting the number of light emitting diodes in the vertical direction is set, and 1 is given to the variable n.

n takes a natural number value up to 25, and when n is smaller than 25, steps 22 to 24 are repeatedly executed, and when n reaches 25, step 25 is executed (step 21). In step 22, the n-th light emitting diode is turned on by the demultiplexer 7 based on the selection command from the control section 6, and at the same time, the detection signal of the light receiving element corresponding to the light emitting diode that is turned on is read into the control section 6 via the multiplexer 4. . In step 23, it is determined whether the light reception level in the read detection signal of the light receiving element has reached a predetermined level. If it has not reached a predetermined level, it is determined that there is a touch operation, and if it has reached it, it is determined that there is no touch operation. . This will be explained based on FIG. Two reference levels L1 and L2 are set in the control section 6 for determining the light receiving level of the light receiving element. Ll indicates the minimum level of light reception generated by directly receiving the light emitted from the light emitting diode, and L2 indicates the light reception level generated by receiving external light. Therefore, in the output value of the A/D converter 5, if the level of the read output signal of the light receiving element does not reach the reference value L1, it is determined that there is an obstacle on the light path and that there is a touch operation, and the reference value When the number is 1 or more, it is determined that there is no touch operation. When it is determined in step 23 that there is no touch operation, n is incremented by 1 in step 24, and steps 22 to 24 are repeated until n reaches 25. When it is determined in step 23 that there is a touch operation, the process moves to the next step 30. Further, all 25 light emitting diodes are caused to emit light, and if it is finally determined that there is no touch operation, the variable n is set to O again in step 25 and the process moves to step 30.

Processing 300 consisting of steps 30 to 35 detects a touch operation by performing a lighting operation on 40 light emitting diodes arranged horizontally in FIG. 1 and reading a detection signal of a corresponding horizontal light receiving element. This is the process to do so. The operation of process 300 corresponds to process 200 described above, and each of steps 30 to 35 strictly corresponds to steps 20 to 25, so a redundant explanation will be omitted here. The difference from vertical touch operation detection is that the number of light emitting diodes is 40, so the variable m must be set (step 30), and in judgment step 31, a determination is made based on whether m has reached 40. The point is that

In the next step 40, it is determined whether a final touch operation has been performed in the vertical and horizontal directions of the touch panel. When both n and m are not 0, it is assumed that a touch operation has been performed, and processing 400 consisting of steps 41 to 43 is executed. Furthermore, when n is 0 or m is 0, the process 500 consisting of steps 51 to 53 is executed as if there was no touch operation.The process 400 consisting of steps 41 to 43 is the process when a touch operation is detected. Yes, first the first counter Ca
Clear to 0 (Step 41), set the lighting period of the light emitting diode to To (Step 42), and start the task corresponding to the detected touch operation position (n, m) (
Step 43).

The counter Ca is a counter for checking how long a touch operation has not been performed, and is therefore cleared to 0 when a touch operation is detected. For the lighting cycle set, the previous lighting cycle is T. In the case of , just T.

is maintained, and when the previous lighting cycle is a long cycle T, the basic cycle T is a short cycle. can be switched to Further, the contents of the task to be activated are stored in the memory of the control unit 6 in correspondence with the location of the touch operation.

Processing 500 consisting of steps 51 to 53 is processing when no touch processing is detected, and in step 51 it is determined whether the count number of counter Ca is greater than or equal to a predetermined value S1. If the content of the counter Ca is smaller than the predetermined value S1, the process moves to step 53 and Ca is incremented by one. When the content of the counter Ca is equal to or greater than the predetermined value S5, the lighting cycle of the light emitting diode is set to the long cycle T1 in step 52. This is because when there is no touch operation on the touch panel for a certain period of time or more, the lighting cycle of the light emitting diode is lengthened to shorten the lighting time and extend its lifespan. In the case of this embodiment, the above-mentioned fixed time S1 is set to, for example, about 1 minute. Therefore, when converting this into the count number of counter Ca, To is 50m8
Therefore, it will be about 1200. Step 52 or 53
After has been executed and after the above-mentioned step 43 has been executed, the process moves to the next step 61.

Process 600 consisting of steps 61 to 63 is a process for determining whether the light emitting diode has reached the end of its life. In this process, a second counter cb is provided to count the number of times the light emitting diode is turned on. counter cb
The counting operation starts when a light emitting diode is newly installed on the touch panel and the touch detection operation is started. Therefore, each time the above processes 200 and 300 are executed, the value is incremented by 1 in step 63 regardless of whether a touch operation is detected or not. Judgment step 6
1, when the contents of the counter cb exceed the predetermined value S2, the controller 6 turns on the alarm lamp 8 in step 62.
A lighting operation command is issued, alarm lamp 8 lights up,
Alert the operator. When cb is smaller than the predetermined value S2, the counter Cb is incremented by one in step 63. The above predetermined value S2 is given as L/Δt, assuming that the lifespan of the light emitting diode is L. In addition,
The count value of counter cb is realized using a nonvolatile memory that is saved even when the power is turned off.

The touch operation point detection operation shown in FIGS. 3A and 3B is executed by the control section 6 according to a program stored in the memory of the control section 6. The features of the touch operation detection device for a touch panel according to the present invention are shown in the flowchart described above, and the device configuration is shown as shown in FIG. 6. In FIG. 6, the touch operation detection device according to the present invention realized by the control unit 6 includes a touch operation point detection command means 71, a period setting means 72, a period changing means 73, a determining means 74, a first counter 75, a 2 counter 76 and driving means 77. Other structures such as the light emitting diode 2, light receiving element 3, multiplexer 4, A/D converter 5, demultiplexer 7, battery 9, etc. are the same as the structure shown in FIG.

The touch operation point detection command means 71 has conventionally been connected to the control section 6.
This is a device configuration installed in a touch panel that outputs a command to detect which part of the touch panel is operated. The period setting means 72 is a means for setting a period for sequentially lighting up the 65 light emitting diodes 2, and is normally set to a short period To. The touch operation point detection command means 71 outputs a touch operation point detection command according to the cycle given from the cycle setting means 72.

The light emitting diodes 2 are sequentially turned on, the output signals of the light receiving elements 3 are sequentially read, and the light receiving level is determined by means 7.
Find out in 4. This determining means 74 determines whether a touch operation has been performed. The first counter 75 counts the time during which the determining means 74 determines that there is no touch operation, and when the count value Ca exceeds the predetermined value S1, the counter 75 outputs a signal to the period changing means 73 to change the period. The period set by the period setting means 72 is changed to the long period T1 via the changing means 73. This aims to extend the life of the light emitting diode 2. Further, each light emitting diode 2 lights up for a period of Δt every time a detection command is issued from the touch operation point detection command means 71. Therefore, by counting the number of times the detection command is generated by the second counter 76, the integral value of the lighting time of each light emitting diode 2 can be measured. When the count value cb of the second counter 76 reaches a predetermined value 82 or more, a drive signal for causing the alarm lamp 8 to perform an alarm operation is generated.

Note that when the determining means 74 detects a touch operation, the period setting means 72 and the second counter 76 are reset to the initially set normal state.

The following modified embodiments of the present invention can be considered. In the above embodiment, the lighting period of the light emitting diode was in two stages, but it can also be configured to be switched in multiple stages. In this case, it is necessary to provide additional conditions for switching. Also, the basic short period T. The relationship between this and the long period T1 when no touch operation is performed for a predetermined amount of time is not limited to five times, and may be set to other magnitude relationships. Furthermore, the multiple can be changed depending on the situation. Instead of the alarm lamp 8, a sound generating means or other alarm generating means may be used.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, when periodically lighting a plurality of light emitting elements to detect a touch operation location, the lighting period is appropriately divided into at least two stages, a short period and a long period. Since the light emitting diode can be adjusted and switched, the life of the light emitting diode can be extended, which has the effect of extending the life of the touch panel itself. In this case, since the configuration is configured to switch from a short cycle to a long cycle in response to the frequency of touch operations on the touch panel, the responsiveness of task activation to touch operations is hardly reduced compared to the previous one. In addition, by counting the integral value of the lighting time of the light emitting element, the lifespan of the light emitting element is predicted and the operator is informed of this, which has the effect of informing the user when it is time to replace the touch panel. arise.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram showing the arrangement of light emitting diodes and light receiving elements in a touch panel; Fig. 2 is a circuit diagram showing the configuration of an electric circuit section for lighting the light emitting diodes and reading detection signals from the light receiving elements; Figure 3A and Figure 3B
The figure is a flowchart showing the control operation for touch operation detection, Figure 4 is a waveform diagram showing the lighting period and lighting time of each light emitting diode, and Figure 5 is for explaining the reference value for determining the light reception level of the light emitting element. and FIG. 6 are functional block diagrams showing the configuration of the touch operation detection device according to the present invention realized by the control section. [Explanation of symbols] 1... Rectangular operation area 2- ・ 3- φ 71 ・ 72 ・ 73 ・ 74 ・ 75 ・ 76 ・ 77 ・ ・ Light emitting diode (LED) ・ Light receiving element / control unit / touch Operation point detection command means, period setting means, period changing means, judgment means, first counter, second counter, driving means Fig. 1

Claims (2)

[Claims] (1) A plurality of light emitting elements arranged on two adjacent sides of the rectangular area for operation, and a plurality of light emitting elements arranged on the other two adjacent sides of the rectangular area in one-to-one correspondence with each of the light emitting elements. Select one of the plurality of light-receiving elements and the light-emitting element to sequentially emit light, read the detection signal of the light-receiving element corresponding to the emitted light-emitting element, detect the light reception level, and determine the location of the touch operation. In the touch operation detection device for a touch panel, the control means has at least a short cycle and a long cycle with respect to the cycle for detecting a touch operation location, Basically, a period setting means for setting the short period, a determining means for determining whether there is a touch operation based on the detection signal of the light receiving element, and a counting means for counting the time during which the determining means determines that there is no touch operation. A touch operation detection device for a touch panel, characterized in that the touch panel has a cycle changing unit that sets a long cycle in the cycle setting unit when the count value of the counting unit exceeds a predetermined value. (2) The touch operation detection device for a touch panel according to claim 1, further comprising an alarm means for issuing an alarm to the operator, and the control means includes another counting means for counting the lighting time of the light emitting element, and another counting means for counting the lighting time of the light emitting element. A touch operation detection device for a touch panel, comprising a drive means for causing the alarm means to perform an alarm operation when the count value of the count means exceeds a predetermined value.