JPH10161812A - Coordinate input device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the electric power that is consumed for the input queuing when the coordinates are detected via a resistance partial pressure type touch panel. SOLUTION: This coordinate input device is provided with a touch panel 5 containing a plastic substrate and a glass substrate which have the transparent conductive films and are placed opposite to each other on one of both sides of the panel 5, the switch elements 7 to 10 which switch the connection between the panel 5 and signals, an A/D conversion part 22 which applies the A/D conversion to the coordinate detection operation at a level of voltage outputted from the panel 5, and a control part 11 which controls the mode, the switching, etc., for the coordinate detection signal operation and also calculates the coordinates. In such a constitution, the transparent conductive films of both plastic and glass substrates set opposite to each other touch with each other only when the panel 5 is pressed. Thus, the applied DC signal undergoes the resistance partial pressure and outputs a coordinate signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to coordinate detection by resistance voltage division type coordinate detection using a touch panel.

[0002]

2. Description of the Related Art In a conventional input device using a resistive voltage dividing type touch panel, an applied DC is applied by pressing the touch panel with a finger or a dedicated input pen.
The signal was output at a voltage value divided by the direct resistance value of the transparent conductive film depending on the pressed position.

[0003]

In the conventional touch panel, even when no input is made, the electrode on the same surface as the electrode to which the DC signal is applied to the touch panel is grounded to the ground. There is a loss of energy consumed by the resistance of the film, and the loss has been a problem when driven by a battery or the like.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the conventional problems, and is directed to a touch panel having a structure in which a plastic substrate having a transparent conductive film on one surface and a glass substrate are opposed to each other via a spacer. A switch element for switching a connection destination between the touch panel and a signal, an A / D conversion unit for A / D converting a coordinate detection signal operation of a voltage level output from the touch panel, and a mode and a switch of the coordinate detection operation. In a coordinate input device having a control unit for controlling switching and calculating coordinates, the applied DC is applied by contacting a transparent conductive film between a plastic substrate and a glass substrate which are opposed to each other only when the touch panel is pressed. The present invention proposes a coordinate input device that outputs a coordinate signal by dividing a signal by resistance.

[0005]

According to the present invention, a touch panel composed of a plastic plate having a transparent conductive film and a glass plate, an analog switch and an FET for switching a coordinate detection axis (X axis / Y axis) and application of a DC signal to the transparent conductive film are provided. Switch elements such as
The control of the switch element and the control unit that A / D converts the coordinate detection signal output at the voltage level to calculate the coordinates allow the touch panel up and down only when the operator touches the touch panel with a finger or a dedicated pen. When the transparent conductive film contacts, the DC signal applied from one conductive film is conducted to the opposing conductive film surface, and the DC signal is divided by the resistance.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a coordinate detection using a touch panel, only when a touch panel surface is pressed, a DC signal applied to one conductive film is conducted to a transparent conductive film on the opposite surface, so that a DC signal is applied. Is divided on the surface of the transparent conductive film opposite to the substrate.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic diagram of the entire resistive voltage dividing touch panel coordinate detecting device using the present invention. Touch panel 5 is shown in FIG.
As shown by, a flexible substrate plastic film 17 having a transparent conductive film 18 made of ITO,
A glass substrate 20 as a fixed substrate having a transparent conductive film 19 made of TO is disposed opposite to a spacer 21 via a spacer 21, and has a configuration in which a plastic film 17 and a glass substrate 20 are stacked.

As a normal coordinate detection operation, in the case of coordinate detection on the X side, when a point P on the touch panel 5 is pressed by a finger or a pen 6, the switch element 10 is switched by a control signal 12 from a control unit 11. Then, the DC signal 15 is applied to the electrode 4 on the touch panel 5. The switch element 9 is a control unit 11
The electrode 2 is connected to the ground by the control signal 12 from. The switch element 8 enters a non-connect state, that is, an electrically floating state, according to a control signal 12 from the control unit 11. One terminal 7-1 of the switch element 7 is connected to the control unit 1
1 is connected to the A / D conversion unit 22 by the control signal 12. A signal subjected to A / D conversion processing by the A / D conversion unit 22 is output to the control unit 11. As a result, the configuration of the device is configured as shown in FIG.

In the actual coordinate signal detection, the DC signal applied from the electrode 4 is applied from the transparent conductive film 19 on the glass plate 20 to the transparent conductive film on the opposite plastic film 17 at the position of the pressed point P on the touch panel 5. 18 is applied.
The DC signal applied to the transparent conductive film 19 is divided into a resistance R1 between the electrode 1 and the point P and a R2 between the electrode 2 and the point P according to the resistance of the transparent conductive film 18 between the electrode 1 and the electrode 2. And
The DC signal applied from the pressing point P is divided by R1 and R2 and output from the electrode 1 because the electrode 2 is ground. The signal from the electrode 1 is transmitted as an output signal 14 to the A / D converter 22 via the terminal 7-1 of the switch element 7. The A / D converter 22 converts the detected signal into an A / D signal.
D-converted and transmitted to the control unit 11. In the control unit 11, A /
The position of the pressed point P on the X-axis is calculated and determined from the signal from the D conversion unit 22.

Next, the case of detecting the coordinate on the Y side will be described. The signal 12 from the control unit 11 has the opposite logic to that at the time of X-side coordinate detection. Control signal 1 for switching control of coordinate detection axis
The switch element switches the connection destination according to the level 2 (Hi or Lo). The switch element 7 for detecting a signal based on the control signal 12 is set so as to apply a DC signal 16 to the electrode 1 of the touch panel 5. One terminal of the switch element 10 is connected to a control signal 12 from the control unit 11.
Thereby, the electrode 4 of the touch panel 5 is connected to the ground. The switch element 9 sets the electrode 2 of the touch panel 5 to a non-connect state according to a control signal 12 from the control unit 11. In the switch element 8, the electrode 2 of the touch panel 5 is connected to the A / D converter 22 by the control signal 12 from the controller 11. The detection signal A / D-converted by the A / D converter 22 is applied to the controller 11. Thus, the configuration of the entire apparatus is configured as shown in FIG.

At the position of the pressed point P on the touch panel 5, a DC signal applied from the electrode 1 is applied from the transparent conductive film 18 of the plastic film 17 to the transparent conductive film 19 of the glass plate 20 facing the same. The DC signal applied to the conductive film 18 includes a resistance R3 between the electrode 3 and the point P, a resistance R3 between the electrode 3 and the point P,
The DC signal applied from the electrode 1 is divided by R3 and R4 and output from the electrode 3 because the electrode 4 is grounded. A signal from the electrode 3 is transmitted as an output signal 13 to the A / D converter 22 via the switch element 8. The A / D converter 22 converts the detected signal into A
/ D conversion and transmission to the control unit 11.
Point P on the Y-axis from the signal from the / D converter 22
Is determined.

Here, the actual operation will be described. FIG.
When the control unit 11 is in a state of waiting for an input to the touch panel 5, the control unit 11 outputs a control signal 12 and outputs the control signals 12, 8,
9 and 10. Depending on whether the logic of the control signal 12 is high or low, each of the switch elements 7, 8, 9, and 10 maintains the signal detection state on the X-axis or Y-axis side. At this time, the state of the selected output signals 13 and 14 on the detection axis side becomes the ground level because one side of the opposite electrode of the same transparent conductive film is connected to the ground. In the case of the state on the X-axis side by the control signal 12 from the control unit 11, the switch element 1
0 switches to the direction in which the DC signal 15 is applied to the electrode 4 of the touch panel 5, the switch element 7 becomes conductive by the control signal 12 from the control unit 11, and connects the electrode 1 of the touch panel 5 to the A / D conversion unit 22. , Output signal to the control unit 1
Connect to 1. (See Fig. 5)

When the touch panel 5 is not pressed with a finger or a pen, the detection signal 14 continues to output the ground level signal as described above. While the output signal 14 is outputting a ground level signal, the control unit 11
Can be recognized that no coordinate detection has been input. At the time of non-input, since the transparent conductive film does not contact, the applied DC signal is not applied to the opposing transparent conductive film surface, so that the voltage dividing process is not performed. The state in which the current consumed by voltage division by the resistance is much smaller than that at the time of coordinate detection is maintained.

Next, the case where the operator presses the point P with the finger or the pen 6 on the touch panel 5 will be described with reference to FIG. When the touch panel 5 is pressed, the touch panel 5
The upper transparent conductive film 18 and the lower transparent conductive film 19 come into contact with each other. As a result, the DC signal 15 applied to the electrode 4 of the touch panel 5 is conducted to the transparent conductive film 19 on the lower side of the touch panel 5, so that the electrode 2 is connected to the ground via the switch element 9. Therefore, R1 between the point P and the electrode 1 and R2 between the point P and the electrode 2
Then, the applied DC signal is divided.

The divided detection signal 14 is detected from the electrode 1 and input to the A / D converter 22 via the terminal 7-1 of the switch element 7. The signal A / D converted by the A / D converter 22 is transmitted to the controller 11. The control unit 11 samples the output signal from the A / D conversion unit 22 at regular time intervals, and confirms pressing on the touch panel 5 when the detection signal is no longer at the ground level. As a result, each of the switch elements 7, 8, 9, 10 is controlled by the control unit 11
, The detection of signals on the X and Y sides is started. By stopping the coordinate detection when the signal level of the detection signal 13 or the detection signal 14 becomes the ground level and shifting to the coordinate input waiting state, the current consumption required for a series of operations can be reduced. In this embodiment, an analog switch has been described as a switch element. However, a similar effect can be obtained by using a field effect transistor (FET).

[0016]

According to the coordinate detecting apparatus of the present invention, the DC signal is applied to the touch panel only when the touch panel is pressed, and the DC signal is conducted to divide the voltage, thereby reducing the power consumption when there is no input to the touch panel. Since the power can be saved without using a dedicated circuit, it can be used for a long time in battery-powered devices and the like.

[Brief description of the drawings]

FIG. 1 is a block diagram of the entire apparatus.

FIG. 2 is a vertical sectional view of a touch panel.

FIG. 3 is an X-side coordinate detection diagram

FIG. 4 is a Y-side coordinate detection diagram.

FIG. 5 is a configuration diagram of a coordinate signal detection circuit.

[Explanation of symbols]

 1 electrode 2 electrode 3 electrode 4 electrode 5 touch panel 6 input pen / finger 7 switch element 8 switch element 9 switch element 10 switch element 11 control unit 12 control signal 13 detection signal 14 detection signal 15 DC signal 16 DC signal 17 plastic film 18 Transparent conductive film 19 Transparent conductive film 20 Glass substrate 21 Spacer 22 A / D converter

Claims (2)

[Claims] 1. A touch panel having a structure in which a plastic substrate having a transparent conductive film on one surface and a glass substrate are opposed to each other via a spacer, a switch element for switching a connection destination between the touch panel and a signal, and an output from the touch panel. The operation of the coordinate detection signal at the voltage level
In a coordinate input device having an A / D conversion unit for performing A / D conversion and a control unit for controlling the coordinate detection operation mode, switching of switches and the like, and calculating coordinates, the A / D conversion unit exists only when the touch panel is pressed. A coordinate input device characterized in that, when a transparent conductive film of a plastic substrate and a glass substrate makes contact with each other, an applied DC signal is subjected to resistance voltage division to output a coordinate signal. 2. The coordinate input device according to claim 1, wherein said switch element comprises an analog switch.