WO2019186939A1

WO2019186939A1 - Touch panel device

Info

Publication number: WO2019186939A1
Application number: PCT/JP2018/013400
Authority: WO
Inventors: 哲平松岡; 知樹奥野
Original assignee: 三菱電機株式会社
Priority date: 2018-03-29
Filing date: 2018-03-29
Publication date: 2019-10-03
Also published as: JPWO2019186939A1; JP6698958B2

Abstract

A touch panel device (100) is provided with: a touch panel (2) that includes a resistance film and that outputs voltage generated at a depressed position (P) in the resistance film in a state where current is flowing through the resistance film; a current supply unit (11) that supplies current to the resistance film; and a current switching unit (12) that switches the current value of current to be supplied from the current supply unit (11) to the resistance film, to either a first current value or a second current value which is less than the first current value. The current switching unit (12) comprises resistors (R21, R23), a resistor (R22) connected to an electrode (223), a resistor (R24) connected to an electrode (213), a switching element (SW21) connected in parallel with the resistor (R21), a switching element (SW22) connected in parallel with the resistor (R22), a switching element (SW23) connected in parallel with the resistor (R23), a switching element (SW24) connected in parallel with the resistor (R24), and a switch control unit (132).

Description

Touch panel device

The present invention relates to a touch panel device.

With a 4-wire resistive touch panel, the power consumption associated with the application of the reference voltage is reduced by lowering the voltage value of the reference voltage of the analog / digital converter if the touch panel is not operated for a preset time or longer. Has been proposed (see, for example, Patent Document 1).

JP 2010-176469 A

However, the touch panel device described in Patent Document 1 can reduce only the power consumption corresponding to a decrease in the reference voltage applied to the analog / digital converter, and the power consumption reduction effect is insufficient.

The present invention has been made in view of the above-described reasons, and an object thereof is to provide a touch panel device that can reduce power consumption.

In order to achieve the above object, a touch panel device according to the present invention includes:
A touch panel that has a resistance film and outputs a voltage generated at a pressed position in the resistance film in a state where a current flows through the resistance film;
A current supply for supplying current to the resistive film;
A current switching unit configured to switch a current value of the current supplied from the current supply unit to the resistance film between a first current value and a second current value smaller than the first current value.

According to the present invention, the current switching unit sets the current value of the current supplied from the current supply unit to the resistance film included in the touch panel to either the first current value or the second current value smaller than the first current value. Switch to. Thereby, since the power consumption consumed by a resistive film can be reduced, the power consumption consumed by the touch panel device can be reduced accordingly.

1 is a block diagram showing a hardware configuration of a touch panel device according to Embodiment 1 of the present invention. The perspective view which shows a part of touchscreen which concerns on Embodiment 1. FIG. FIG. 3 is a block diagram showing a functional configuration of the touch panel device according to Embodiment 1. The flowchart which shows an example of the flow of the touchscreen drive process which concerns on Embodiment 1. FIG. The figure for demonstrating the detection method of the coordinate value of the X-axis direction of the pressing-down position of the touchscreen apparatus which concerns on Embodiment 1. FIG. The figure for demonstrating the detection method of the coordinate value of the Y-axis direction of the pressing position of the touchscreen apparatus which concerns on Embodiment 1. FIG. The circuit diagram which shows the equivalent circuit when the switching element which concerns on Embodiment 1 is an OFF state The circuit diagram which shows the equivalent circuit when the switching element which concerns on Embodiment 1 is an ON state The figure which shows the voltage which has arisen in position S1, S2, P, T1, T2 shown to FIG. 6A and FIG. 6B 4 is a time chart illustrating an example of the operation of the switching element according to the first embodiment. 4 is a time chart illustrating an example of the operation of the switching element according to the first embodiment. The flowchart which shows an example of the flow of the operation mode command process which concerns on Embodiment 1. The figure which shows the position of the coordinate determined that the touchscreen is not touched by the user which concerns on Embodiment 1. The block diagram which shows the function structure of the touchscreen apparatus which concerns on Embodiment 2 of this invention. The flowchart which shows an example of the flow of the operation mode command process which concerns on Embodiment 2. The figure which shows an example of the initial screen image displayed on the display part which concerns on Embodiment 2. FIG. The figure which shows an example of the menu screen image displayed on the display part which concerns on Embodiment 2. FIG. The figure which shows an example of the confirmation screen image displayed on the display part which concerns on Embodiment 2. FIG. The flowchart which shows an example of the flow of the operation mode command process which concerns on Embodiment 2. The figure which shows the position of the coordinate determined that the touchscreen is not touched by the user which concerns on a modification The figure which shows the position of the coordinate determined that the touchscreen is not touched by the user which concerns on a modification The figure which shows the position of the coordinate determined that the touchscreen is not touched by the user which concerns on a modification The figure which shows the position of the coordinate determined that the touchscreen is not touched by the user which concerns on a modification The figure which shows the position of the coordinate determined that the touchscreen is not touched by the user which concerns on a modification

(Embodiment 1)
Hereinafter, the touch panel device according to Embodiment 1 of the present invention will be described with reference to the accompanying drawings. The touch panel device according to the present embodiment includes a touch panel that has a resistance film and outputs a voltage generated at a pressed position in the resistance film in a state where current flows through the resistance film, and a current that supplies current to the resistance film A supply unit; and a current switching unit that switches a current value of the current supplied from the current supply unit to the resistance film to either a first current value or a second current value smaller than the first current value. Then, the current switching unit appropriately switches the current value of the current supplied from the current supply unit to the resistance film of the touch panel to the second current value, thereby reducing the power consumption in the resistance film.

As shown in FIG. 1, a touch panel device 100 according to the present embodiment includes a touch panel 2, a touch panel drive circuit 1, a CPU (Central Processing Unit) 3, a main storage unit 4, and an auxiliary storage unit 5. Prepare. The touch panel device 100 is used as a remote control device that controls, for example, a lighting device, a ventilation device, and other devices installed in a building. The main storage unit 4 is a volatile memory and is used as a work area for the CPU 3. The auxiliary storage unit 5 is a non-volatile memory such as a magnetic disk or a semiconductor flash memory, and stores programs for realizing various functions of the touch panel device 100.

As shown in FIG. 2, the touch panel 2 includes a fixed electrode plate 21 and a movable electrode plate 22 disposed to face the fixed electrode plate 21. In FIG. 2, one direction orthogonal to the thickness direction of the fixed electrode plate 21 is defined as the X-axis direction, and one direction orthogonal to the thickness direction of the fixed electrode plate 21 and the X-axis direction is defined as the Y-axis direction. The direction orthogonal to the Y-axis direction is taken as the Z-axis direction. Between the fixed electrode plate 21 and the movable electrode plate 22, for example, a plurality of dot-like spacers (not shown) arranged in a lattice shape are provided.

The fixed electrode plate 21 includes a transparent first substrate (not shown), a transparent resistance film 211 stacked on the surface of the first substrate on the + Z direction side, and a pair of

electrodes

212 and 213. The pair of

electrodes

212 and 213 are arranged apart from each other in the Y-axis direction orthogonal to the thickness direction of the resistance film 211 in the resistance film 211. The movable electrode plate 22 includes a transparent second substrate (not shown) having flexibility, a transparent resistance film 221 laminated on the surface of the second substrate on the −Z direction side, and a pair of

electrodes

222 and 223. And having. The pair of

electrodes

222 and 223 are arranged apart from each other in the X-axis direction orthogonal to the thickness direction of the resistance film 221 in the resistance film 221. The material of the first substrate is transparent glass, resin, or the like. The material of the second substrate is, for example, transparent polyethylene terephthalate. The material of the

resistance films

211 and 221 is, for example, ITO (indium tin oxide). The material of the

electrodes

212, 213, 222, and 223 is, for example, a conductive material containing silver. The user can operate the touch panel 2 by pressing the movable electrode plate 22 from the + Z direction side so that the resistance film 211 of the fixed electrode plate 21 and the resistance film 221 of the movable electrode plate 22 are brought into contact with each other. The current that flows from one of the pair of

electrodes

212 and 213 to the other is uniform in the plane of the resistance film 211, and the current that flows from one of the pair of

electrodes

222 and 223 to the other is uniform in the plane of the resistance film 221. is there.

The touch panel drive circuit 1 operates in two operation modes: a normal mode and a current limiting mode that limits a current flowing through the

resistance films

211 and 221 of the touch panel 2 as compared to the normal mode operation. As shown in FIG. 3, the touch panel drive circuit 1 includes a current supply unit 11 that supplies current to the

resistance films

211 and 221 of the touch panel 2, and eight switching elements SW11, SW12, SW13, SW14, SW21, SW22, SW23, SW24. The touch panel drive circuit 1 further includes four resistors R21, R22, R23, and R24, a microcomputer 13, and a memory 14. Here, the switching elements SW11, SW12, SW13, SW14, SW21, SW22, SW23, and SW24 are, for example, FETs (Field-Effect Transistors), bipolar transistors, semiconductor relays, and the like. Moreover, these switching elements SW11, SW12, SW13, SW14, SW21, SW22, SW23, and SW24 may be realized using a general-purpose logic IC. The memory 14 is a semiconductor memory, for example. The current supply unit 11 includes a constant voltage circuit, and supplies a current to the

resistance films

211 and 221 via the current switching unit 12 by outputting a constant voltage to the current switching unit 12. Note that the CPU 3 may have the function of the microcomputer 13. Further, the memory 14 may be realized by the auxiliary storage unit 5.

The resistor R21 is a first resistor connected to the electrode 222 that is electrically connected to the current supply unit 11 via the switching element SW11 among the pair of

electrodes

222 and 223 arranged in the X-axis direction on the touch panel 2. The resistor R21 is interposed between the electrode 222 and the switching element SW11. The first resistor R23 is a first resistor connected to the electrode 212 that is electrically connected to the current supply unit 11 via the switching element SW13 among the pair of

electrodes

212 and 213 arranged in the Y-axis direction on the touch panel 2. . The resistor R23 is interposed between the electrode 212 and the switching element SW13. The resistor R22 is a second resistor having one end electrically connected to the electrode 223 of the two

electrodes

222 and 223 and the other end grounded via the switching element SW12. The resistor R24 is a second resistor having one end electrically connected to the electrode 213 of the two

electrodes

212 and 213 and the other end grounded via the switching element SW14. Here, the resistance value of the resistor R21 and the resistance value of the resistor R22 are equal to each other, and the resistance value of the resistor R23 and the resistance value of the resistor R24 are equal to each other.

Switching element SW21 is a first switching element connected in parallel to resistor R21, and switching element SW23 is a first switching element connected in parallel to resistor R23. The switching element SW22 is a second switching element connected in parallel to the resistor R22, and the switching element SW24 is a second switching element connected in parallel to the resistor R24.

The microcomputer 13 includes analog / digital converters (hereinafter referred to as “ADC”) 131X and 131Y, a switch control unit 132, and a coordinate calculation unit 133. The ADC 131Y is connected between the resistor R22 and the switching element SW22 and the switching element SW12. The ADC 131X is connected between the resistor R24 and the switching element SW24 and the switching element SW14. The input resistances of the ADC 131X and ADC 131Y are sufficiently higher than the resistance values of the

resistance films

211 and 221 and the resistance values of the resistances R21, R22, R23, and R24.

The ADCs 131 X and 131 Y generate voltages generated at the pressing positions in the

resistance films

211 and 221 when the user presses the touch panel 2 in a state where the current supply unit 11 supplies current to the

resistance films

211 and 221 of the touch panel 2. It is a voltage value output part which outputs the reflected value. For example, it is assumed that the user presses the touch panel 2 and the

resistance films

211 and 221 are in contact with each other at the pressing position P in the

resistance films

211 and 221 as shown in FIG. Here, when the current supply unit 11 applies a voltage only between the

electrodes

222 and 223 of the movable electrode plate 22, as shown in FIG. 3, the voltage generated at the pressing position P of the resistance film 221 is applied to the ADC 131X. Is input through the resistance film 211 and the electrode 213. Then, the ADC 131X outputs a value reflecting the voltage generated at the pressed position P of the resistance film 221. At this time, the ADC 131Y outputs a value reflecting the ground potential.

On the other hand, when the current supply unit 11 applies a voltage only between the

electrodes

212 and 213 of the fixed electrode plate 21 shown in FIG. 2, as shown in FIG. Is input via the resistance film 221 and the electrode 223. The ADC 131Y outputs a value reflecting the voltage generated at the pressed position P of the resistance film 211. At this time, the ADC 131X outputs a value reflecting the ground potential.

The coordinate calculation unit 133 calculates coordinate values on the

resistance films

211 and 221 at the pressed position P on the touch panel 2 based on the output values of the

ADCs

131X and 131Y, and generates coordinate information indicating the calculated coordinate values.

The switch control unit 132 controls the ON / OFF of each of the switching elements SW11, SW12, SW13, SW14, SW21, SW22, SW23, and SW24, thereby changing the current value of the current supplied to the

resistance films

211 and 221 to the first current. The value is switched to either a value or a second current value smaller than the first current value. The switch control unit 132 includes a counter (not shown) that is counted up in synchronization with the internal clock of the microcomputer 13 and a register (not shown) that holds a preset reference value for the count value of the counter. Have. Then, after switching all of the switching elements SW21, SW22, SW23, and SW24 between the on state and the off state, the switch control unit 132 calculates the coordinates of the switching completion notification signal when the count value of the counter reaches the reference value. Output to the unit 133. In this way, the switch control unit 132 switches all of the switching elements SW21, SW22, SW23, and SW24 between the on state and the off state, and then sends a switching completion notification signal after the lapse of the reference time corresponding to the reference value. Output to the coordinate calculation unit 133. The switch control unit 132, the four switching elements SW21, SW22, SW23, and SW24 and the four resistors R21, R22, R23, and R24 are included in the current switching unit 12. The current switching unit 12 switches the current value of the current supplied from the current supply unit 11 to the

resistance films

211 and 221 to either a first current value or a second current value smaller than the first current value.

The memory 14 includes a correlation information storage unit 141 that stores first correlation information and second correlation information representing a relational expression indicating a correlation between the output values of the

ADCs

131X and 131Y and the coordinates in the X-axis direction and the Y-axis direction. This relational expression is expressed by a linear function for obtaining a coordinate value in the X-axis direction or the Y-axis direction, for example, using the voltage value of the voltage generated at the pressed position P as an argument. Here, the first correlation information indicates a correlation between the output values of the

ADCs

131X and 131Y and the coordinate values when the touch panel drive circuit 1 operates in the current limiting mode. The second correlation information indicates a correlation between the output values of the

ADCs

131X and 131Y and the coordinate values when the touch panel drive circuit 1 operates in the normal mode.

The display unit 6 is a liquid crystal display device, for example, and displays various types of information represented by characters, figures, and the like. The display unit 6 is disposed so as to overlap the touch panel 2 in the thickness direction of the resistance film 211 of the touch panel 2. The display unit 6 is arranged such that its display area (not shown) is located inside a range where the user can perform a pressing operation on the touch panel 2 when viewed from the thickness direction of the touch panel 2.

The CPU 3 functions as the determination unit 31, the command unit 32, the processing unit 33, the display control unit 34, and the time measuring unit 35 by reading the program stored in the auxiliary storage unit 5 into the main storage unit 4 and executing it. The auxiliary storage unit 5 includes an image information storage unit 51, a processing information storage unit 52, an operation mode storage unit 53, and a threshold information storage unit 54. The image information storage unit 51 stores image information indicating various images corresponding to the operation screen displayed on the display unit 6. When the operation button image indicating the operation button is included in the corresponding image, the image information stores the operation information indicating the operation content corresponding to the operation button image in association with the operation button image.

The processing information storage unit 52 stores processing information indicating processing contents corresponding to various operation information indicating various operation contents on the touch panel 2. The operation mode storage unit 53 stores operation mode information indicating whether the touch panel drive circuit 1 is operating in the normal mode or the current limiting mode. That is, the operation mode information indicates whether the switching elements SW21, SW22, SW23, and SW24 of the touch panel drive circuit 1 are in the first state where the switching elements SW21, SW22, SW23, and SW24 are in the on state or the second state where the switching elements SW21, SW22, SW23, and SW24 are in the off state. State information. The operation mode storage unit 53 is a state information storage unit that stores operation mode information that is state information.

The threshold information storage unit 54 stores coordinate threshold information and elapsed time threshold information. The coordinate threshold information indicates coordinate thresholds for the coordinate value in the X-axis direction and the coordinate value in the Y-axis direction of the touch panel 2. The elapsed time threshold value information indicates an elapsed time threshold value with respect to the elapsed time from when the coordinate value calculated by the coordinate calculation unit 133 of the touch panel drive circuit 1 first becomes equal to or less than the coordinate threshold value. Here, the coordinate threshold values for the coordinate values in the X-axis direction and the coordinate values in the Y-axis direction are set based on the coordinate values calculated by the coordinate calculation unit 133 in a state where the user does not press the touch panel 2. The elapsed time threshold is set based on the duration of the no-operation state in which it can be determined that the user has finished operating the touch panel 2.

The determination unit 31 determines whether or not the user has pressed the touch panel 2 based on the coordinate value calculated by the coordinate calculation unit 133. Here, the determination unit 31 determines whether or not the user has pressed a preset first area on the touch panel 2 based on the coordinate value calculated by the coordinate calculation unit 133. Further, the determination unit 31 acquires image identification information for identifying image information corresponding to the operation screen displayed on the display unit 6 from the display control unit 34, and an image corresponding to the image identification information acquired from the image information storage unit 51. Get information. Then, the determination unit 31 compares the position of the image indicating the operation button included in the image information with the coordinates calculated by the coordinate calculation unit 133, and determines whether or not an operation for selecting the operation button has been performed by the user. To do. When determining that the operation for selecting the operation button has been performed, the determination unit 31 notifies the processing unit 33 of operation information corresponding to the operation button.

When the determination unit 31 determines that the touch panel 2 has not been pressed, the command unit 32 gives off command information for instructing the switching elements SW21, SW22, SW23, and SW24 to be turned off to the switch control unit of the touch panel drive circuit 1. It outputs to 132. On the other hand, when the determination unit 31 determines that the user has pressed a preset first area on the touch panel 2, the command unit 32 instructs the switching elements SW21, SW22, SW23, and SW24 to be turned on. Information is output to the switch control unit 132 of the touch panel drive circuit 1. Here, the off command information and the on command information are adapted to a specific communication protocol, for example.

When the operation information is notified from the determination unit 31, the processing unit 33 acquires processing information corresponding to the operation information notified from the processing information storage unit 52, and executes processing based on the acquired processing information. When the processing unit 33 needs to update the operation screen to be displayed on the display unit 6 as a result of executing the processing, the processing unit 33 controls display of image update request information including image identification information of image information indicating the updated operation screen. Notification to the unit 34.

When the image update request information is notified from the processing unit 33, the display control unit 34 acquires the image information corresponding to the image identification information included in the notified image update request information from the image information storage unit 51, and acquires the image information. An operation screen corresponding to the image information is displayed on the display unit 6. The timer unit 35 is, for example, a software timer, and notifies the determination unit 31 of time information indicating the time.

The main storage unit 4 has a time storage area for storing time information when the above-described determination unit 31 first determines that the coordinate values in the X-axis direction and the Y-axis direction are each equal to or less than the coordinate threshold value.

Next, touch panel drive processing executed by the touch panel drive circuit 1 according to the present embodiment will be described with reference to FIGS. The touch panel driving process is started when the touch panel device 100 is powered on, for example. Here, description will be made assuming that the touch panel drive circuit 1 is initially operating in the normal mode. That is, the description will be made assuming that the switching elements SW21, SW22, SW23, and SW24 are all initially turned on.

First, as shown in FIG. 4, the switch control unit 132 turns on the switching elements SW11 and SW12 (step S101). At this time, as shown in FIG. 5A, the current supply unit 11 applies a constant voltage Vc only between the

electrodes

222 and 223 of the movable electrode plate 22. Here, if the user presses the pressing position P, the

resistance films

211 and 221 are in contact with each other at the pressing position P. In this case, the ADC 131X outputs an output value reflecting the voltage generated at the pressed position P of the resistance film 221. At this time, a circuit formed between the current supply unit 11 and the ground potential is represented by an equivalent circuit shown in FIG. 6A. The voltage generated at the pressing position P of the resistance film 221 is expressed by the following formula (1).
Vx [P: ON] = {(Rx2 + Rt) / (Rs + Rx1 + Rx2 + Rt)} × Vc
... Formula (1)
Here, Vx [P: ON] represents a voltage generated at the pressing position P of the resistance film 221, and Vc represents a voltage output from the current supply unit 11. Rx1 represents the equivalent resistance in the X-axis direction between the pressing position P in the resistance film 221 and the electrode 222, and Rx2 represents the equivalent in the X-axis direction between the pressing position P in the resistance film 221 and the electrode 223. Represents resistance. Further, Rs represents a resistance component between the electrode 222 and the switching element SW21, and Rt represents a resistance component between the electrode 223 and the switching element SW22. These resistance components Rs and Rt are, for example, wiring resistances. As shown in FIG. 6C, the voltage Vx [P: ON] is a voltage in the range of the dynamic range ΔVON according to the pressed position P.

Returning to FIG. 4, next, the ADC 131 X sets a value reflecting the voltage V [P: ON] generated at the pressing position P of the resistance film 221 input via the resistance film 211 and the electrode 213, as a coordinate calculation unit 133. (Step S102). At this time, the ADC 131Y outputs a value reflecting the ground potential. And the coordinate calculation part 133 acquires only the value output from ADC131X. Subsequently, the switch control unit 132 turns off the switching elements SW11 and SW12 (step S103).

Thereafter, the switch control unit 132 turns on the switching elements SW13 and SW14 (step S104). At this time, as shown in FIG. 5B, the current supply unit 11 applies a constant voltage Vc only between the

electrodes

212 and 213 of the fixed electrode plate 21. Here, when the user presses down the pressing position P and the

resistance films

211 and 221 come into contact with each other at the pressing position P, the ADC 131Y outputs an output reflecting the voltage generated at the pressing position P of the input resistance film 211. Output the value. At this time, the voltage generated at the pressing position P of the resistance film 211 is expressed by the following formula (2).
Vy [P: ON] = {(Ry2 + Rt) / (Rs + Ry1 + Ry2 + Rt)} × Vc
... Formula (2)
Here, Vy [P: ON] represents a voltage generated at the pressing position P of the resistance film 221, and Vc represents a voltage output from the current supply unit 11. Ry1 represents the equivalent resistance in the Y-axis direction between the pressing position P in the resistance film 211 and the electrode 212, and Ry2 represents the equivalent resistance in the Y-axis direction between the pressing position P in the resistance film 211 and the electrode 213. Represents resistance. Further, Rs represents a resistance component between the electrode 212 and the switching element SW23, and Rt represents a resistance component between the electrode 213 and the switching element SW24. As shown in FIG. 6C, the voltage Vy [P: ON] is a voltage in the range of the dynamic range ΔVON according to the pressed position P.

Returning to FIG. 4, next, the ADC 131 Y sets a value reflecting the voltage Vy [P: ON] generated at the pressing position P of the resistance film 211 input via the resistance film 221 and the electrode 223 as a coordinate calculation unit 133. (Step S105). At this time, the ADC 131X outputs a value reflecting the ground potential. And the coordinate calculation part 133 acquires only the value output from ADC131Y. Subsequently, the switch control unit 132 turns off the switching elements SW13 and SW14 (step S106).

Thereafter, the coordinate calculation unit 133 calculates the coordinate value in the X-axis direction and the coordinate value in the Y-axis direction of the pressed position P based on the values acquired from the ADC 131X and ADC 131Y, and the coordinate information indicating the calculated coordinate value Is generated and output to the CPU 3 (step S107). Here, the coordinate calculation unit 133 acquires the correlation information corresponding to the normal mode from the correlation information storage unit 141, and calculates the coordinate value using the relational expression indicated by the acquired correlation information. As described above, this relational expression obtains a coordinate value in the X-axis direction (Y-axis direction) using, for example, the voltage value of the voltage Vx [P: ON] (Vy [P: ON]) generated at the pressed position P as an argument. Expressed by a linear function.

Next, the switch control unit 132 determines whether or not the current limiting mode command information for instructing the touch panel drive circuit 1 to operate in the current limiting mode is input from the CPU 3 (step S108). If the switch control unit 132 determines that the current limiting mode command information is not input (step S108: No), the process of step S111 described later is executed. On the other hand, when the switch control unit 132 determines that the current limiting mode command information has been input (step S108: Yes), it turns off all the switching elements SW21, SW22, SW23, and SW24 (step S109). Subsequently, the coordinate calculation unit 133 changes the correlation information to be used to the correlation information corresponding to the current limiting mode (step S110). Here, as shown in FIG. 7A, the switch controller 132 turns the switching elements SW21, SW22, SW23, and SW24 off at time T11, and then coordinates the switching completion notification signal at time T12 when the reference time ΔT1 has elapsed. Output to the calculation unit 133. On the other hand, when the switch completion notification signal is input from the switch control unit 132, the coordinate calculation unit 133 changes the correlation information to be used to the correlation information corresponding to the current limiting mode.

Thereafter, the switch control unit 132 determines whether or not normal mode command information for instructing the touch panel drive circuit 1 to operate in the normal mode is input from the CPU 3 (step S111). When the switch control unit 132 determines that the normal mode command information is not input (step S111: No), the switch control unit 132 turns on the switching elements SW11 and SW12 again (step S101). At this time, as described above, the current supply unit 11 is in a state in which the constant voltage Vc is applied only between the

electrodes

222 and 223 of the movable electrode plate 22. Here, when the user presses down the pressing position P and the

resistance films

211 and 221 come into contact with each other at the pressing position P, the ADC 131X reflects a voltage generated at the pressing position P of the input resistance film 221. Is output. At this time, a circuit formed between the current supply unit 11 and the ground potential is represented by an equivalent circuit shown in FIG. 6B. The voltage generated at the pressing position P of the resistance film 221 is expressed by the following formula (3).
Vx [P: OFF] = {(Rx2 + Rt + R22) / (R21 + Rs + Rx1 + Rx2 + Rt + R22)} × Vc
... Formula (3)
Here, Vx [P: OFF] represents a voltage generated at the pressing position P of the resistance film 221, and Vc, Rx1, Rx2, Rs, and Rt are the same as those in the above-described formula (1). R21 and R22 indicate resistance values of the resistors R21 and R22, respectively. In this case, the voltage Vx [P: ON] is a voltage in the range of the dynamic range ΔVOFF according to the pressed position P, as shown in FIG. 6C. The range of ΔVOFF is narrower than the range of ΔVON. Accordingly, the length corresponding to the resolution in the X-axis direction and the Y-axis direction during the current-limiting mode operation of the touch panel drive circuit 1 corresponds to the resolution in the X-axis direction and the Y-axis direction during the normal mode operation of the touch panel drive circuit 1. It will be longer than you want.

Returning to FIG. 4, next, the ADC 131 X sets a value reflecting the voltage V [P: OFF] generated at the pressing position P of the resistance film 221 input through the resistance film 211 and the electrode 213, as a coordinate calculation unit 133. (Step S102), the coordinate calculation unit 133 acquires only the value output from the ADC 131X. Subsequently, the switch control unit 132 turns off the switching elements SW11 and SW12 (step S103).

Thereafter, the switch control unit 132 turns on the switching elements SW13 and SW14 (step S104). At this time, as described above, the current supply unit 11 is in a state in which the constant voltage Vc is applied only between the

electrodes

212 and 213 of the fixed electrode plate 21. Here, when the user presses the position P and the

resistance films

211 and 221 come into contact with each other at the position P, the ADC 131Y outputs a value reflecting the voltage generated at the pressed position P of the resistance film 211. To do. At this time, the voltage generated at the pressing position P of the resistance film 211 is expressed by the following formula (4).
Vy [P: OFF] = {(Ry2 + Rt + R24) / (R23 + Rs + Ry1 + Ry2 + Rt + R24)} × Vc
... Formula (4)
Here, Vy [P: OFF] represents a voltage generated at the pressing position P of the resistance film 211, and Vc, Ry1, Ry2, Rs, and Rt are the same as those in the above-described formula (2). R23 and R24 indicate resistance values of the resistors R23 and R24, respectively. As shown in FIG. 6C, the voltage Vy [P: OFF] is a voltage in a range of a dynamic range ΔVOFF that is narrower than the range of the dynamic range ΔVON according to the pressed position P. Therefore, the length corresponding to the resolution in the Y-axis direction during the current-limiting mode operation of the touch panel drive circuit 1 is longer than the length corresponding to the resolution in the Y-axis direction during the normal mode operation of the touch panel drive circuit 1.

Returning to FIG. 4, next, the ADC 131 Y sets a value reflecting the voltage Vy [P: OFF] generated at the pressing position P of the resistance film 211 input via the resistance film 221 and the electrode 223, as a coordinate calculation unit 133. (Step S105). And the coordinate calculation part 133 acquires only the value output from ADC131Y. Subsequently, the switch control unit 132 turns off the switching elements SW13 and SW14 (step S106). Thereafter, the process of step S107 is executed again.

If the switch control unit 132 determines in step S111 described above that normal mode command information has been input (step S111: Yes), the switching elements SW21, SW22, SW23, and SW24 are all turned on again (step S112). . Thereafter, the coordinate calculation unit 133 changes the correlation information to be used to the correlation information corresponding to the normal mode (step S113). Here, as shown in FIG. 7B, the switch control unit 132 turns on the switching elements SW21, SW22, SW23, and SW24 at time T21, and then coordinates the switching completion notification signal at time T22 when the reference time ΔT1 has elapsed. Output to the calculation unit 133. On the other hand, when the switch completion notification signal is input from the switch control unit 132, the coordinate calculation unit 133 changes the correlation information to be used to the correlation information corresponding to the normal mode. Next, the process of step S101 is executed again.

By the way, when the touch panel drive circuit 1 operates in the normal mode, when only the switching elements SW11 and SW12 are turned on, the first current value which is the current value of the current flowing through the resistance film 221 is sufficiently high for the input resistance of the ADC 131X. Since it is high, it is represented by the following relational expression (5).
Ix [ON] = Vc / (Rs + Rx1 + Rx2 + Rt) (5)
Here, Ix [ON] indicates a first current value of the current flowing through the resistance film 221. Note that Vc, Rs, Rt, Rx1, and Rx2 are the same as those in the formula (1). Further, when only the switching elements SW13 and SW14 are turned on, the first current value which is the current value of the current flowing through the resistance film 211 is sufficiently high because the input resistance of the ADC 131Y is sufficiently high. It is represented by
Iy [ON] = Vc / (Rs + Ry1 + Ry2 + Rt) (6)
Here, Iy [ON] indicates the first current value of the current flowing through the resistance film 211. Vc, Rs, Rt, Ry1, and Ry2 are the same as in the case of the formula (2).

On the other hand, when the touch panel drive circuit 1 operates in the current limiting mode, the input resistance of the ADC 131X is sufficient for the second current value, which is the current value of the current flowing through the resistance film 221 when only the switching elements SW11 and SW12 are turned on. Therefore, it is expressed by the relational expression of the following formula (7).
Ix [OFF] = Vc / (R21 + Rs + Rx1 + Rx2 + Rt + R22) (7)
Here, Ix [OFF] indicates a second current value of the current flowing through the resistance film 221. Note that Vc, Rs, Rt, Rx1, Rx2, R21, and R22 are the same as those in the formula (3). Further, when only the switching elements SW13 and SW14 are turned on, the second current value that is the current value of the current flowing through the resistance film 221 is sufficiently high because the input resistance of the ADC 131Y is sufficiently high. It is represented by
Iy [OFF] = Vc / (R23 + Rs + Ry1 + Ry2 + Rt + R24) (8)
Here, Iy [OFF] indicates a second current value of the current flowing through the resistance film 211. Note that Vc, Rs, Rt, Ry1, Ry2, R23, and R24 are the same as those in the formula (4).

Then, from the equations (5) to (8), the following equations (9) and (10) are established.
Ix [OFF] / Ix [ON] = (Rs + Rx1 + Rx2 + Rt) / (R21 + Rs + Rx1 + Rx2 + Rt + R22) (9)
Iy [OFF] / Iy [ON] = (Rs + Ry1 + Ry2 + Rt) / (R21 + Rs + Ry1 + Ry2 + Rt + R22) (10)

From Equation (9) and Equation (10), Ix [OFF] / Ix [ON] and Iy [OFF] / Iy [ON] are both less than 1, that is, the current switching unit 12 is a current supply unit. 11 from the first current value Ix [ON] (Iy [ON]) to the first current value Ix [ON] (Iy [ON]) smaller than the first current value Ix [ON] (Iy [ON]). 2 Switch to the current value Ix [OFF] (Iy [OFF]). Thereby, the operation mode of the touch panel drive circuit 1 is switched from the normal mode to the current limiting mode.

Next, operation mode command processing executed by the touch panel device 100 according to the present embodiment will be described with reference to FIG. This operation mode command processing is started when the touch panel device 100 is powered on, for example. Further, it is assumed that the operation mode storage unit 53 initially stores operation mode information indicating that the touch panel drive circuit 1 is in the normal mode.

First, the determination unit 31 acquires coordinate information output from the coordinate calculation unit 133 of the touch panel drive circuit 1 (step S201). Next, the determination unit 31 acquires coordinate threshold information from the threshold information storage unit 54, the coordinate value Xdet in the X-axis direction indicated by the coordinate information is equal to or less than the coordinate threshold Xth, and the coordinate value Ydet in the Y-axis direction is the coordinate threshold value. It is determined whether or not Yth or less (step S202). When the user does not touch the touch panel 2, the coordinate value Xdet in the X-axis direction indicated by the coordinate information is equal to or less than the coordinate threshold value Xth, and the coordinate value Ydet in the Y-axis direction is equal to or less than the coordinate threshold value Yth. In other words, when the coordinate information indicates the coordinates in the area ARd1 indicated by the cross hatch shown in FIG. 9, it is determined that the touch panel 2 is not touched by the user. Returning to FIG. 8, it is assumed that the determination unit 31 determines that the coordinate value Xdet in the X-axis direction is equal to or less than the coordinate threshold value Xth and the coordinate value Ydet in the Y-axis direction is equal to or less than the coordinate threshold value Yth (step S202: Yes). ). In this case, based on the time information input from the time measuring unit 35, the determination unit 31 first has the coordinate value Xdet in the X axis direction equal to or less than the coordinate threshold value Xth and the coordinate value Ydet in the Y axis direction equal to or less than the coordinate threshold value Yth The elapsed time from the time when it is determined to be is calculated (step S203). Assume that the determination unit 31 first determines that the coordinate value Xdet in the X-axis direction is equal to or less than the coordinate threshold value Xth and the coordinate value Ydet in the Y-axis direction is equal to or less than the coordinate threshold value Yth. In this case, the determination unit 31 acquires the time information at that time from the time measuring unit 35 and stores it in the time storage area of the main storage unit 4 described above.

Next, the determination unit 31 acquires elapsed time threshold information from the threshold information storage unit 54, and determines whether or not the calculated elapsed time is equal to or greater than the elapsed time threshold indicated by the acquired elapsed time threshold information (step S204). ). When determining that the elapsed time is less than the elapsed time threshold indicated by the acquired elapsed time threshold information (step S204: No), the determination unit 31 executes the process of step S201 again. On the other hand, it is assumed that the determination unit 31 determines that the elapsed time is equal to or greater than the elapsed time threshold indicated by the acquired elapsed time threshold information (step S204: Yes). In this case, the command unit 32 refers to the operation mode information stored in the operation mode storage unit 53 and determines whether or not the operation mode of the touch panel drive circuit 1 is the current limiting mode (step S205). If the command unit 32 determines that the operation mode of the touch panel drive circuit 1 is the current limiting mode (step S205: Yes), the process of step S201 is executed again.

On the other hand, it is assumed that the command unit 32 determines that the operation mode of the touch panel drive circuit 1 is the normal mode (step S205: No). In this case, the command unit 32 sends off command information for commanding the switching elements SW21, SW22, SW23, and SW24 to be turned off to the switch control unit 132 of the touch panel drive circuit 1 in order to place the touch panel drive circuit 1 in the current limiting mode. Output (step S206). Subsequently, the process of step S201 is executed again.

In step S202, the determination unit 31 determines that the coordinate value Xdet in the X-axis direction is larger than the coordinate threshold value Xth or that the coordinate value Ydet in the Y-axis direction is larger than the coordinate threshold value Yth (step S202). : No). In this case, the command unit 32 refers to the operation mode information stored in the operation mode storage unit 53, and determines whether or not the operation mode of the touch panel drive circuit 1 is the current limiting mode (step S207). If the command unit 32 determines that the operation mode of the touch panel drive circuit 1 is the normal mode (step S207: No), the process of step S201 is executed again.

On the other hand, it is assumed that the command unit 32 determines that the operation mode of the touch panel drive circuit 1 is the current limiting mode (step S207: Yes). In this case, the command unit 32 outputs to the switch control unit 132 of the touch panel drive circuit 1 on command information for commanding to turn on the switching elements SW21, SW22, SW23, and SW24 in order to place the touch panel drive circuit 1 in the normal mode. (Step S208). Subsequently, the process of step S201 is executed again.

As described above, in the touch panel device 100 according to the present embodiment, the current switching unit 12 sets the current value of the current supplied from the current supply unit 11 to the

resistance films

211 and 221 included in the touch panel 2 as the first current. The value is switched to either a value or a second current value smaller than the first current value. Thereby, since the power consumption consumed by the

resistance films

211 and 221 can be reduced, the power consumption consumed by the touch panel device 100 can be reduced accordingly.

Further, when the touch panel drive circuit 1 according to the present embodiment operates in the current limiting mode, as shown in FIG. 6C, the potential generated at an arbitrary pressing position P in the

resistance films

211 and 221 is higher than the ground potential. Become. As a result, the noise component included in the voltages input to the

ADCs

131X and 131Y can be easily removed, so that the erroneous recognition of the pressed position P due to the noise component is suppressed.

Furthermore, in the touch panel drive circuit 1 according to the present embodiment, the resistance value of the resistor R21 and the resistance value of the resistor R22 are equal, and the resistance value of the resistor R23 and the resistance value of the resistor R24 are equal to each other. Thereby, when the touch panel drive circuit 1 operates in the normal mode, the voltage generated at the center of the

resistance films

211 and 221 is equal to the voltage generated at the center of the

resistance films

211 and 221 when operated in the current limiting mode. Become. Therefore, for example, when it is necessary to update the correlation information stored in the correlation information storage unit 141 with a change in resistance values of the

resistance films

211 and 221 with the passage of time, the voltage generated at the center of the

resistance films

211 and 221 is used as a reference. New correlation information can be generated. Therefore, there is an advantage that generation of new correlation information is simplified.

In touch panel device 100 according to the present embodiment, when determining unit 31 determines that touch panel 2 has not been pressed for a preset elapsed time threshold or more, command unit 32 switches off command information. Output to the control unit 132. This prevents the user from operating the touch panel 2 without being operated for a long time while the touch panel drive circuit 1 is operating in the normal mode, so that the power consumption of the touch panel device 100 is reduced.

Furthermore, in touch panel device 100 according to the present embodiment, determination unit 31 is based on the coordinate value calculated by coordinate calculation unit 133, and is set in advance on touch panel 2 by the user, that is, the coordinate in the X-axis direction. It is determined whether or not an area whose value is equal to or greater than the coordinate threshold value Xth and whose coordinate value in the Y-axis direction is equal to or greater than the coordinate threshold value Yth is pressed. When the determination unit 31 determines that the user has pressed the above-described area on the touch panel 2, the on-command information is output to the switch control unit 132. Accordingly, it is possible to select an effect of reducing power consumption by appropriately changing the coordinate threshold values Xth and Yth to change the frequency with which the touch panel drive circuit 1 is operated in the current limiting mode.

In addition, the touch panel drive circuit 1 according to the present embodiment includes first correlation information indicating the correlation between the output values of the

ADCs

131X and 131Y and the coordinate values when operating in the current limiting mode, and when operating in the normal mode. A correlation information storage unit 141 that stores second correlation information indicating the correlation between the output values of the

ADCs

131X and 131Y and the coordinate values is provided. Thereby, the coordinate calculation part 133 can calculate a coordinate value accurately in each of the case where the touchscreen drive circuit 1 operate | moves in a current-limiting mode, and the case where it operates in normal mode.

(Embodiment 2)
The touch panel device according to the present embodiment causes the touch panel drive circuit to operate in either the normal mode or the current limiting mode in accordance with the type of operation screen image displayed on the display unit. Specifically, in the touch panel device according to the present embodiment, the size and interval of the operation button image included in the operation screen image displayed on the display unit corresponds to the resolution of the touch panel during the current limiting mode operation of the touch panel drive circuit. If it is less than the length to be operated, the touch panel drive circuit is operated in the normal mode. On the other hand, when the size and interval of the operation button image included in the operation screen image displayed on the display unit is greater than or equal to the length corresponding to the resolution of the touch panel during the current limiting mode operation of the touch panel drive circuit, the touch panel device The drive circuit is operated in a current limiting mode. That is, the touch panel device operates the touch panel drive circuit in the current limiting mode when the specification of the operation screen image matches the resolution of the touch panel during the current limiting mode operation of the touch panel drive circuit.

As shown in FIG. 10, in the touch panel device 200 according to the present embodiment, the CPU 3 reads out and executes the program stored in the auxiliary storage unit 5 to the main storage unit 4, thereby determining the determination unit 31, the command unit 232, It functions as the processing unit 233 and the display control unit 34. The auxiliary storage unit 5 includes an image information storage unit 51 and a processing information storage unit 52. In FIG. 10, the same reference numerals as those in FIG. The hardware configuration of touch panel device 200 is the same as that of touch panel device 100 according to the first embodiment.

The processing unit 233 acquires processing information corresponding to the notified operation information from the processing information storage unit 52, and executes processing based on the acquired processing information. Further, the processing unit 233 determines whether or not an event for displaying the confirmation screen image on the display unit 6 has occurred as a result of executing the processing. If the processing unit 233 determines that an event for displaying the confirmation screen image on the display unit 6 has occurred, the processing unit 233 notifies the instruction unit 232 of a confirmation screen display event occurrence notification.

The command unit 232 is instructed to turn off the switching elements SW21, SW22, SW23, and SW24 according to the image information indicating the operation screen image displayed on the display unit 6 or to turn on these commands. ON command information to be output to the switch control unit 132. Command unit 232 has a case in which the size and interval of the operation button image included in the operation screen image displayed on display unit 6 is less than or equal to the length corresponding to the resolution of touch panel 2 when the touch panel drive circuit 1 operates in the current limiting mode. The ON command information is output to the switch control unit 132. On the other hand, the command unit 232 determines that the size and interval of the operation button image included in the operation screen image displayed on the display unit 6 is longer than the length corresponding to the resolution of the touch panel 2 when the touch panel drive circuit 1 operates in the current limiting mode. If it is longer, the off command information is output to the switch control unit 132. That is, the command unit 232 outputs the off command information to the switch control unit 132 when the specification of the operation screen image matches the resolution of the touch panel 2 when the touch panel drive circuit 1 operates in the current limiting mode. In the present embodiment, the size and interval of the operation button images included in the initial screen image and the confirmation screen image are equal to or longer than the length corresponding to the resolution of the touch panel 2 when the touch panel drive circuit 1 operates in the current limiting mode. It is assumed that the size and interval of the operation button image included in the screen image is shorter than the length corresponding to the resolution of the touch panel 2 when the touch panel drive circuit 1 operates in the current limiting mode. When receiving a confirmation screen display event occurrence notification from processing unit 233, command unit 232 outputs off command information to switch control unit 132.

Next, operation mode command processing executed by the touch panel device 200 according to the present embodiment will be described with reference to FIGS. This operation mode command processing is started when the touch panel device 200 is powered on, for example. Further, in this operation mode command process, when a confirmation screen image for confirming execution of a process set in advance by the user is displayed on the display unit 6, an operation button is selected to accept the execution of the process by the user. Then, after the processing is executed, an initial screen image is displayed on the display unit 6.

First, the command unit 232 outputs to the switch control unit 132 of the touch panel drive circuit 1 off command information that commands the switching elements SW21, SW22, SW23, and SW24 to be turned off in order to set the touch panel drive circuit 1 to the current limiting mode. (Step S301). Next, the display control unit 34 acquires initial screen information indicating an initial screen image from the image information storage unit 51, and causes the display unit 6 to display an initial screen image corresponding to the acquired initial screen information (step S302). For example, as shown in FIG. 12A, the initial screen image 61a is an image including one operation button image B1 having a vertical width ΔY1 and a horizontal width ΔX1 at the center. Note that the initial screen image is not limited to this, and other arbitrary graphic images or character information may be arranged.

Returning to FIG. 11, subsequently, the determination unit 31 acquires coordinate information from the coordinate calculation unit 133 of the touch panel drive circuit 1 (step S303), and the user selects an operation button based on the coordinate value indicated by the coordinate information. Whether or not (step S304). Here, the determination unit 31 is a coordinate value of a position where the coordinate value in the X-axis direction and the coordinate value in the Y-axis direction indicated by the coordinate information acquired from the coordinate calculation unit 133 are included in the inner region of the operation button image B1. If so, it is determined that the operation button has been selected. As long as it is determined that the user has not selected the operation button (step S304: No), the determination unit 31 repeats the process of step S303.

On the other hand, it is assumed that the determination unit 31 determines that the user has selected the operation button (step S304: Yes). In this case, the command unit 32 outputs to the switch control unit 132 on command information for commanding to turn on the switching elements SW21, SW22, SW23, and SW24 in order to set the touch panel drive circuit 1 to the normal mode (step S305). . Thereafter, the display control unit 34 acquires menu screen information indicating the menu screen image from the image information storage unit 51, and causes the display unit 6 to display a menu screen image corresponding to the acquired menu screen information (step S306). For example, as shown in FIG. 12B, the menu screen image 62a is an image in which a plurality of operation button images B2 having a vertical width of ΔY21 and a horizontal width of ΔX21 are arranged in a grid pattern with an interval of ΔY22 in the vertical direction and ΔX22 in the horizontal direction. is there. Here, the lengths ΔX21 and ΔX22 are longer than the length corresponding to the resolution in the X-axis direction of the touch panel 2 when the touch panel drive circuit 1 operates in the normal mode. Further, the lengths ΔX21 and ΔX22 are equal to or shorter than the length corresponding to the resolution in the X-axis direction of the touch panel 2 when the touch panel drive circuit 1 operates in the current limiting mode. The lengths ΔY21 and Δ22 are longer than the length corresponding to the resolution in the Y-axis direction when the touch panel drive circuit 1 is in the normal mode operation. The lengths ΔY21 and Δ22 are equal to or shorter than the length corresponding to the resolution in the Y-axis direction when the touch panel drive circuit 1 is in the current limiting mode operation. The menu screen image is not limited to this, and other arbitrary graphic images or character information may be arranged.

Returning to FIG. 11, subsequently, the determination unit 31 acquires coordinate information from the coordinate calculation unit 133 of the touch panel drive circuit 1 (step S307), and the user selects an operation button based on the coordinate value indicated by the coordinate information. It is determined whether or not (step S308). Here, the determination unit 31 includes the coordinate value in the X-axis direction and the coordinate value in the Y-axis direction indicated by the coordinate information acquired from the coordinate calculation unit 133, in each of the inner regions of the plurality of operation button images B2. If it is a coordinate value of the position to be operated, it is determined that the operation button has been selected. The determination unit 31 repeats the process of step S307 as long as it is determined that the user has not selected an operation button (step S308: No).

On the other hand, it is assumed that the determination unit 31 determines that the user has selected the operation button (step S308: Yes). In this case, the determination unit 31 notifies the processing information corresponding to the operation button to the processing unit 233 (step S309), and the processing unit 233 receives the processing information corresponding to the notified operation information from the processing information storage unit 52. Acquire and execute processing based on the acquired processing information (step S310). Thereafter, as illustrated in FIG. 13, the processing unit 233 determines whether or not an event for displaying the confirmation screen image on the display unit 6 has occurred as a result of executing the processing (step S 311). When it is determined by the processing unit 233 that an event for displaying the confirmation screen image on the display unit 6 has occurred (step S311: Yes), the processing unit 233 notifies the instruction unit 232 of a confirmation screen display event occurrence notification. Then, when notified of the confirmation screen display event occurrence notification, the command unit 232 outputs the off command information to the switch control unit 132 (step S312).

Next, the display control unit 34 acquires confirmation screen information indicating the confirmation screen image from the image information storage unit 51, and causes the display unit 6 to display a menu screen image corresponding to the acquired menu screen information (step S313). For example, as shown in FIG. 12C, the confirmation screen image 63a is an image in which two operation button images B31 and B32 having a vertical width of ΔY31 and a horizontal width of ΔX3 are arranged at an interval of ΔY32 in the vertical direction. The two operation button images B31 and B32 correspond to a “YES” button and a “NO” button, respectively. Here, the length ΔX3 is longer than the length corresponding to the resolution in the X-axis direction of the touch panel 2 when the touch panel drive circuit 1 operates in the current limiting mode. Further, the lengths ΔY31 and Δ32 are longer than the length corresponding to the resolution in the Y-axis direction of the touch panel 2 when the touch panel drive circuit 1 operates in the current limiting mode. Note that the confirmation screen image is not limited to this, and other arbitrary graphic images or character information may be arranged.

Returning to FIG. 13, subsequently, the determination unit 31 acquires coordinate information from the coordinate calculation unit 133 of the touch panel drive circuit 1 (step S 314), and the user presses the “YES” button based on the coordinate value indicated by the coordinate information. It is determined whether or not it has been selected (step S315). Here, the determination unit 31 is an area inside the operation button image B31 in which the coordinate value in the X-axis direction and the coordinate value in the Y-axis direction indicated by the coordinate information acquired from the coordinate calculation unit 133 correspond to the “YES” button. If it is the coordinate value of the position included in, it is determined that the “YES” button has been selected. When determining that the user has selected the “YES” button (step S315: Yes), the determining unit 31 notifies the processing unit 233 of operation information corresponding to the “YES” button (step S316). Thereafter, the processing unit 233 acquires processing information corresponding to the notified operation information from the processing information storage unit 52, and executes processing based on the acquired processing information (step S317). Next, as shown in FIG. 11, the display control unit 34 acquires the initial screen information from the image information storage unit 51 again and displays the initial screen image on the display unit 6 (step S302). Then, the process after step S303 is performed.

Returning to FIG. 13, if the determination unit 31 determines that the user has not selected the “YES” button (step S315: No), the determination unit 31 determines whether the user has selected the “NO” button ( Step S318). Here, the determination unit 31 is an area inside the operation button image B32 in which the coordinate value in the X-axis direction and the coordinate value in the Y-axis direction indicated by the coordinate information acquired from the coordinate calculation unit 133 correspond to the “NO” button. If it is the coordinate value of the position included in, it is determined that the “NO” button has been selected. If it is determined that the user has not selected the “NO” button (step S318: No), the determination unit 31 executes the process of step S314 again. The determination unit 31 repeatedly executes the processes of steps S314, S315, and S318 unless the user selects either the “YES” button or the “NO” button.

On the other hand, when the determination unit 31 determines that the user has selected the “NO” button (step S318: Yes), the command unit 32 outputs the ON command information to the switch control unit 132 (step S319). Thereafter, as shown in FIG. 11, the display control unit 34 again acquires the menu screen information from the image information storage unit 51 and displays the menu screen image on the display unit 6 (step S306). Then, the process after step S307 is performed.

Returning to FIG. 13, when it is determined in step S 311 that the event for displaying the confirmation screen image on the display unit 6 has not occurred (step S 311: No), the processing unit 233 displays the image on the display unit 6. It is determined whether or not an event that requires the operation screen image to be updated has occurred (step S320). If it is determined by the processing unit 233 that an event that requires the operation screen image to be updated has not occurred (step S320: No), the processing from step S307 shown in FIG. 11 is executed as it is. On the other hand, when it is determined that an event that requires an operation screen image update has occurred (step S320: Yes), the processing unit 233 receives image update request information including image identification information of image information indicating the updated operation screen. The display control unit 34 is notified. Then, the display control unit 34 acquires image information corresponding to the image identification information included in the image information storage unit 51 or the image update request information, and causes the display unit 6 to display the operation screen image indicated by the acquired image information ( Step S321). Next, the process after step S307 shown in FIG. 11 is performed.

As described above, according to the touch panel device 200 according to the present embodiment, the touch panel drive circuit 1 is operated in the current limiting mode at any time according to the operation screen image displayed on the display unit 6. As a result, the frequency with which the touch panel drive circuit 1 operates in the current limiting mode increases, and accordingly, power consumption in the touch panel drive circuit 1 is reduced.

The embodiment of the present invention has been described above, but the present invention is not limited to the embodiment. For example, the touch panel device may execute the operation mode command process according to the first embodiment and the operation mode command process according to the second embodiment in parallel.

In the first embodiment, when a time equal to or greater than the elapsed time threshold elapses when the user does not operate the touch panel 2, the command unit 32 outputs the off command information to the switch control unit 132, and the touch panel drive circuit 1 is in the current limiting mode. An example of operation has been described. However, the timing at which the command unit 32 outputs the off command information to the switch control unit 132 is not limited to this. For example, the command unit 32 may output the off command information to the switch control unit 132 when the elapsed time from the activation of the touch panel device 100 is equal to or greater than a preset time threshold. Alternatively, the display control unit 34 may display a setting screen image for setting the operation mode of the touch panel drive circuit 1 on the display unit 6. In this case, when the determination unit 31 determines that the operation button for operating the touch panel drive circuit 1 in the current limiting mode is selected in the state where the setting screen image is displayed on the display unit 6, the command unit 32 The off command information may be output to the switch control unit 132.

This configuration increases the frequency with which the touch panel drive circuit 1 operates in the current limiting mode as compared to the touch panel device 100 according to the embodiment. Therefore, the power consumption in the touch panel drive circuit 1 is reduced accordingly.

In Embodiment 1, the coordinate threshold values Xth and Yth can be set arbitrarily. In the first embodiment, when the determination unit 31 indicates the coordinates in the area ARd2 where the coordinate information Ydet indicated by the cross-hatched portion in FIG. 14A is equal to or less than the coordinate threshold Yth, the touch panel 2 It may be determined that is not touched. Alternatively, the determination unit 31 indicates that the touch panel 2 is not touched when the coordinate value Xdet in the X-axis direction indicated by the cross hatch portion in FIG. 14B indicates a coordinate in the area ARd3 that is equal to or less than the coordinate threshold value Xth. You may judge. Further, the determination unit 31 has a coordinate value Xdet in the X-axis direction whose coordinate information is indicated by the cross-hatched portion in FIG. 15A or less in the area ARd4 where the coordinate value Ydet in the Y-axis direction is less than or equal to the coordinate threshold value Yth. When the coordinates are shown, it may be determined that the touch panel 2 is not touched.

Further, the determination unit 31 uses the two coordinate threshold values Xth1 and Xth2 in the X-axis direction and the two coordinate threshold values Yth1 and Yth2 in the Y-axis direction to determine whether or not the touch panel 2 is touched by the user. May be determined. For example, the coordinate value Xdet in the X-axis direction is the coordinate threshold value Xth1 or less or the coordinate threshold value Xth2 or more, and the coordinate value Ydet in the Y-axis direction is the coordinate threshold value. When the coordinates in the area ARd5 that are Yth1 or less or the coordinate threshold Yth2 or more are indicated, it may be determined that the touch panel 2 is not touched. Here, the area ARd5 corresponds to the areas (1), (2), (3), (4), (6), (7), (8), and (9) in FIG. 15B. Alternatively, for example, when the determination unit 31 indicates the coordinates in the area ARd6 where the coordinate information is indicated by the cross-hatched portion in FIG. 16 and the coordinate value Xdet in the X-axis direction is equal to or less than the coordinate threshold value Xth1 or the coordinate threshold value Xth2 It may be determined that the touch panel 2 is not touched. Here, the area ARd6 corresponds to the areas (1), (3), (4), (6), (7), and (9) in FIG. 15B. Note that the coordinates indicated by the coordinate information when the determination unit 31 determines that the touch panel 2 is not touched are not limited to the coordinates in the areas ARd5 and ARd6 illustrated in FIGS. 15B and 16. For example, the coordinates indicated by the coordinate information are in the areas (1), (2), (3), (4), (6), (7), (8), and (9) shown in FIGS. 15B and 16. If the touch panel 2 is not touched, the determination unit 31 may determine that the touch panel 2 is not touched.

In the second embodiment, the dimensions and intervals of the operation button images included in the initial screen image and the confirmation screen image displayed on the display unit 6 correspond to the resolution of the touch panel 2 when the touch panel drive circuit 1 operates in the current limiting mode. The example which is more than length was demonstrated. However, an operation screen image in which the size and interval of the operation button image included in the operation screen image is longer than the length corresponding to the resolution of the touch panel 2 in the current limiting mode operation of the touch panel drive circuit 1 is the initial screen image and the confirmation screen. It is not limited to images. When the touch panel device 200 displays on the display unit 6 various operation screen images that are longer than the length corresponding to the resolution of the touch panel 2 during the current limiting mode operation of the other touch panel driving circuit 1, the touch panel driving circuit 1 is limited. You may operate in flow mode. In this case, for example, the image information storage unit 51 may store various operation screen images in association with current limiting mode flag information indicating whether to operate in the current limiting mode. Then, the command unit 232 may output the off command information to the switch control unit 132 according to the content of the current limiting mode flag information corresponding to the operation screen image displayed on the display unit 6.

In each embodiment, in the touch panel drive circuit 1 according to the present embodiment, an example in which the resistance value of the resistor R21 and the resistance value of the resistor R22 are equal, and the resistance value of the resistor R23 and the resistance value of the resistor R24 are equal to each other. explained. However, not limited to this, the resistance value of the resistor R21 and the resistance value of the resistor R22 may be different from each other, or the resistance value of the resistor R23 and the resistance value of the resistor R24 may be different from each other. In this case, since the degree of freedom of the specification of the resistors used as the resistors R21, R22, R23, and R24 increases, there is an advantage that the touch panel drive circuit 1 can be easily manufactured.

In the touch panel drive circuit 1 according to each embodiment, either one of the resistors R21 and R22 may be omitted, or one of the resistors R23 and R24 may be omitted. In this case, the number of parts of the touch panel drive circuit 1 can be reduced.

An example in which the correlation information stored in the correlation information storage unit 141 according to each embodiment represents a relational expression indicating the correlation between the voltage values of the output voltages of the

ADCs

131X and 131Y and the coordinates in the X-axis direction and the Y-axis direction will be described. did. However, the correlation information is not limited to the one showing the relational expression, and may be a lookup table showing the correlation between the voltage values of the output voltages of the

ADCs

131X and 131Y and the coordinates in the X-axis direction and the Y-axis direction. Good.

In each embodiment, the example in which all the switching elements SW21, SW22, SW23, and SW24 are turned off when the touch panel drive circuit 1 operates in the current limiting mode has been described. However, not limited to this, for example, when the touch panel drive circuit 1 operates in the current limiting mode, only one of the switching elements SW21 and SW22 and only one of the switching elements SW23 and SW24 are off. May be.

In each embodiment, the coordinate calculation unit 133 uses the voltage value of the voltage generated at each of two preset positions on the touch panel 2 and the voltage value of the voltage generated at the pressed position P based on the voltage value of the pressed position P. The coordinate values in the X-axis direction and the Y-axis direction may be calculated. Alternatively, the coordinate calculation unit 133 may determine the X position of the pressed position P based on the voltage value of the voltage generated at each of three or more preset positions on the touch panel 2 and the voltage value of the voltage generated at the pressed position P. Alternatively, the coordinate value in the Y-axis direction may be calculated.

In each embodiment, the touch panel device 100 may include a light source, a speaker, or a vibration source. Then, when the operation mode of the touch panel drive circuit 1 is changed from the normal mode to the current limiting mode, the light source may be turned on or blinked. Alternatively, the light source may be turned on while the touch panel drive circuit 1 is operating in the normal mode, and the light source may be turned off while being operated in the current limiting mode. Further, when the operation mode of the touch panel drive circuit 1 is changed from the normal mode to the current limiting mode, the speaker may notify the user that the operation mode is changed, or the vibration source operates and the touch panel is operated. The entire device 100 may vibrate.

Further, various functions of the touch panel device 100 according to the present invention may be realized by software, firmware, or a combination of software and firmware. In this case, software or firmware is described as a program and stored in the auxiliary storage unit 5. In addition, various functions of the touch panel device 100 according to the present invention can be realized by using a computer system without depending on a dedicated system. For example, a non-temporary recording medium (flexible disc, CD-ROM (Compact Disc-Read-Only Memory), DVD) that can be read by a computer system is stored in a computer connected to a network. (Digital Versatile Disc), MO (Magneto-Optical Disc), etc. may be stored and distributed, and the program may be installed in a computer system to constitute the touch panel device 100 that executes the above-described processing.

方法 Also, the method of providing the program to the computer is arbitrary. For example, the program may be uploaded to a server on a communication line and distributed to a computer via the communication line. Then, the computer activates this program and executes it in the same manner as other applications under the control of an OS (Operating System). Accordingly, the computer functions as the touch panel device 100 that executes the above-described processing.

As mentioned above, although each embodiment and modification of this invention (including what was written in the description, the same is true hereafter) were described, this invention is not limited to these. The present invention includes a combination of the embodiments and modifications as appropriate, and a modification appropriately added thereto.

The present invention is suitable for a touch panel device used as a lighting device, a ventilation device, and other remote control devices for controlling devices installed in a building.

1 touch panel drive circuit, 2 touch panel, 3 CPU, 4 main storage unit, 5 auxiliary storage unit, 6 display unit, 11 current supply unit, 12 switching unit, 13 microcomputer, 14 memory, 21, 22 electrode plate, 31 determination unit, 32,232 command unit, 33,233 processing unit, 34 display control unit, 35 timing unit, 51 image information storage unit, 52 processing information storage unit, 53 operation mode storage unit, 54 threshold information storage unit, 61a initial screen image, 62a menu screen image, 63a confirmation screen image, 100, 200 touch panel device, 131X, 131Y analog / digital converter, 132 switch control unit, 133 coordinate calculation unit, 141 correlation information storage unit, 211, 221 resistance film, 212, 213 , 222, 223 Electrodes, B1, B2, B31, B3 Operation button image, L1, L2 straight line, P pressed position, S1, S2, T1, T2 position, R21, R22, R23, R24, Rx1, Rx2, Ry1, Ry2 resistance, SW11, SW12, SW13, SW14, SW21, SW22 , SW23, SW24 switching element

Claims

A touch panel that has a resistance film and outputs a voltage generated at a pressed position in the resistance film in a state where a current flows through the resistance film;
A current supply for supplying current to the resistive film;
A current switching unit that switches a current value of a current supplied from the current supply unit to the resistance film to either a first current value or a second current value smaller than the first current value;
Touch panel device.
The touch panel
The electrode further includes a pair of electrodes arranged apart from each other in the resistance film,
The current switching unit is
A first resistor inserted between the one of the pair of electrodes electrically connected to the current supply unit and the current supply unit;
A second resistor electrically connected to the other of the pair of electrodes;
A first switching element connected in parallel to the first resistor;
A second switching element connected in parallel to the second resistor;
By controlling on / off of the first switching element and the second switching element, the current value of the current supplied to the resistance film is switched between the first current value and the second current value. A switch control unit,
The resistance value of the first resistor and the resistance value of the second resistor are equal to each other.
The touch panel device according to claim 1.
A voltage value output unit that outputs a value reflecting a voltage generated at a pressing position in the resistance film when a user presses the touch panel in a state where the current supply unit supplies current to the resistance film;
A determination unit for determining whether or not the user has pressed the touch panel;
A command unit that outputs, to the switch control unit, off command information that commands the first switching element and the second switching element to be turned off when the determination unit determines that the touch panel is not pressed. And further comprising
The touch panel device according to claim 2.
Based on a value reflecting the voltage, further comprising a coordinate calculation unit for calculating a coordinate value on the resistance film of the pressed position,
The determination unit determines whether or not the user has pressed the touch panel based on the coordinate value calculated by the coordinate calculation unit.
The touch panel device according to claim 3.
The determination unit further determines, based on the coordinate value calculated by the coordinate calculation unit, whether or not a preset area on the touch panel has been pressed by the user,
The command unit is configured to command an on command to turn on the first switching element and the second switching element when the determination unit determines that the user has pressed a preset area on the touch panel. Outputting information to the switch controller;
The touch panel device according to claim 4.
First correlation information indicating a correlation between a value reflecting the voltage and the coordinate value when the first switching element and the second switching element are in an OFF state; the first switching element; and the second switching element. A correlation information storage unit for storing second correlation information indicating a correlation between a value reflecting the voltage when the element is in an ON state and the coordinate value;
The coordinate calculation unit calculates the coordinate value based on the first correlation information when the first switching element and the second switching element are in an OFF state, and the first switching element and the second switching element When the and are in the ON state, the coordinate value is calculated based on the second correlation information.
The touch panel device according to claim 4 or 5.
Stores state information indicating whether the first switching element and the second switching element are both in the first state in which the first switching element and the second switching element are in the on state or the second state in which the first switching element and the second switching element are in the off state. A status information storage unit
The touch panel device according to any one of claims 3 to 6.
A display unit arranged to overlap the touch panel in the thickness direction of the resistive film;
A display control unit for displaying an operation screen image on the display unit,
The command unit is configured to turn off the first switching element and the second switching element according to image information indicating an operation screen image displayed on the display unit, or the first commanding unit. On-command information for commanding to turn on the switching element and the second switching element is output to the switch control unit,
The touch panel device according to any one of claims 3 to 7.
When the specification of the operation screen image displayed on the display unit matches the resolution of the touch panel when the first switching element and the second switching element are in an off state, the command unit And off command information for commanding to turn off the second switching element to the switch control unit,
The touch panel device according to claim 8.