JPH06168071A - Device and method for inputting position information - Google Patents

Abstract

PURPOSE:To remove an unsuitable coordinate generated by the fluctuation of an output coordinate and to obtain position information which is always stable in a position information input device using a tablet. CONSTITUTION:The number of samplings in an A/D conversion circuit is set by a control signal SA, plural temporary coordinate positions for the designation position this time are taken, and they are stored in a register group 22. Distances between the respective temporary coordinate positions and the previous coordinate position which is previously stored in a register 23 are respectively calculated, and the temporary coordinate position where the distance of the both positions have an intermediate value is selected, and it is outputted as a true coordinate position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position information input device using a pressure-sensitive tablet or the like applied to a touch panel type input device, and particularly to a position information input device capable of obtaining stable position information. Position information input method.

[0002]

2. Description of the Related Art Conventionally, a touch panel type input device has been developed as an input device of, for example, a small document creation device or a personal computer. This touch panel type input device is a position (coordinate) input device using a pressure-sensitive tablet.

As shown in FIG. 8, the touch panel includes two transparent electrode members 3, between a transparent film substrate 1 forming the surface of the panel and a glass substrate 2 forming the bottom.
4 are opposed to each other with a gap, and an insulating spacer (insulating dot spacer) 5 is provided in this gap.

Each of the transparent electrode materials 3 and 4 has a transparent electrode surface coated with a transparent conductive film, and has an X-axis electrode material (hereinafter referred to as an X-axis transparent electrode 3) and a Y-axis electrode material (hereinafter referred to as an X-axis electrode material). The Y-axis transparent electrode 4). The insulating spacer 5 prevents contact between the X-axis transparent electrode 3 and the Y-axis transparent electrode 4 during a non-input operation, and is deformed when the film substrate 1 is pressed with a pen or the like to short-circuit between the transparent electrodes 3 and 4. It is a spherical member. Below the glass substrate 2, for example, a liquid crystal display (LCD) 6 for displaying a screen of a key arrangement corresponding to a keyboard is arranged.

The principle of such a touch panel is that when a designated position on the film substrate 1 is pressed with a pen or the like, the X-axis transparent electrode 3 and the Y-axis transparent electrode 4 come into contact with each other, and the X-axis coordinate corresponding to the designated position is obtained. An input signal (analog voltage signal) corresponding to the Y-axis coordinate is generated. This analog signal is converted into a digital signal to detect the position information of the designated position.
From the relationship between this position information and the key arrangement displayed on the LCD 6, for example, the same key input data as when the designated key input is operated can be generated.

[0006]

By the way, conventionally, in the position information input device using the tablet as described above,
Since the voltage value at one point at the specified position is measured, the output coordinates may fluctuate due to noise due to static electricity.
There was a problem of getting inappropriate coordinates (which are called jump coordinates) away from the specified position.

The present invention has been made in view of the above points, and eliminates inappropriate coordinates caused by variations in output coordinates, and a position information input device and position information input that can always obtain stable position information. The purpose is to provide a method.

[0008]

According to the present invention, in a position information input device using a tablet, a voltage signal corresponding to each of an X coordinate position and a Y coordinate position of a designated position is sampled, and a predetermined number for the designated position is sampled. , The distance between each of these temporary coordinate positions and the previous coordinate position is calculated, and the temporary coordinate position having the intermediate distance between the two is calculated as the true coordinate with respect to the specified position. The position is determined.

[0009]

According to the above construction, a plurality of temporary coordinate positions with respect to the designated position are taken, and the temporary coordinate position having an intermediate value with respect to the previous coordinate position is determined as the true coordinate position. As a result, it is possible to eliminate inappropriate coordinates caused by fluctuations in output coordinates, and always obtain stable position information.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. In FIG. 1, this device comprises a touch panel 10 and a control device 11. The touch panel 10 has an X-axis transparent electrode 3 and a Y-axis transparent electrode 4, and has a structure as shown in FIG. The control device 11 detects the coordinates of the input position P pressed by the pen or the like on the touch panel 10 based on the voltage signals alternately output from the X-axis transparent electrode 3 and the Y-axis transparent electrode 4 in a time division manner.

The control device 11 has switches XG and XV connected to the voltage measuring electrodes A and B of the X-axis transparent electrode 3 and a switch Y connected to the voltage measuring electrodes C and D of the Y-axis transparent electrode 4.
It has a G, YV, a DC power supply 12, an A / D conversion circuit 13 and a control circuit 14. The switch XG is an X-axis transparent electrode 3
The connection between the voltage measurement electrode A and the ground terminal (negative voltage output terminal) of the DC power supply 12 is turned on / off. Switch Y
G is a voltage measuring electrode C of the Y-axis transparent electrode 4 and a DC power source 12
Turn on / off the connection with the ground terminal of. On the other hand, the switch XV includes the voltage measuring electrode B of the X-axis transparent electrode 3 and the DC power source 1
The connection with the voltage output terminal (plus voltage output terminal) 2 is turned on / off. The switch YV turns on / off the connection between the voltage measuring electrode D of the Y-axis transparent electrode 4 and the voltage output terminal of the DC power supply 12.

The A / D conversion circuit 13 has a multiplexer function and has a two-channel first input terminal Vi0 and a second input terminal Vi1. The ground terminal of the DC power supply 12 is connected to the ground terminal GND. In addition, the first input terminal Vi0
A voltage measuring electrode B is connected to the second input terminal Vi1.
A voltage measuring electrode D is connected to the. The A / D conversion circuit 13 has a first input terminal Vi0 by the multiplexer function.
And each voltage value (analog signal) applied to the second input terminal Vi1 is selectively converted into a digital signal. The control circuit 14 calculates the position information consisting of the X-axis coordinates and the Y-axis coordinates of the input position P based on the digital signal output from the A / D conversion circuit 13, and here the switch X is used.
It outputs a control signal SW1 for controlling switching of G, XV and switches YG, YV, and also outputs a control signal SA for setting a sampling period T in the A / D conversion circuit 13.

FIG. 2 is a block diagram showing the configuration of the control circuit 14. The control circuit 14 has a microprocessor (hereinafter referred to as CPU) 21, a register group 22 and a register 23. The CPU 21 controls the entire control circuit 14, and here executes a coordinate determination process as shown in FIG. The register group 22 includes a plurality of registers 1 to n, and stores a plurality of coordinate positions (X-axis and Y-axis coordinates) obtained from the A / D conversion circuit 13, respectively. The register 23 stores the previous coordinate position (X-axis and Y-axis coordinate). Next, the operation of the embodiment will be described.

First, as a basic operation, the control circuit 14
Controls the switches XG, XV and the switches YG, YV in a time division manner, and alternately detects the X axis coordinate position and the Y axis coordinate position of the input position P in a time division manner.

Specifically, the control circuit 14 causes the control signal SW to
Is output, the switches XG and XV are turned on, and the switch Y
Keep G and YV off. When the switches XG and XV are turned on, a circuit including the voltage measuring electrode B of the X-axis transparent electrode 3, the DC power supply 12, and the voltage measuring electrode A is formed. At this time, when the input position P is pressed on the touch panel 10 with a pen or the like, the X-axis transparent electrode 3 and the Y-axis transparent electrode 4 are pressed.
And are short-circuited at the input position P.

In this state, as shown in FIG.
The voltage V from the DC power supply 12 is applied between the electrodes B and A. At this time, the second input terminal V of the A / D conversion circuit 13
By connecting the measurement electrode D of the Y-axis transparent electrode 4 to i1,
The voltage between the input position P and the electrode A is input. As a result, the A / D conversion circuit 13 converts the voltage signal between the input position P and the electrode A into a digital signal and outputs it to the control circuit 14 as the X-axis coordinate position of the input position P.

On the other hand, the control circuit 14 controls the switches XG and XV.
When the switch is turned off and the switches YG and YV are turned on, a circuit composed of the voltage measuring electrode D of the Y-axis transparent electrode 4, the DC power supply 12 and the voltage measuring electrode C is formed.

In this state, as shown in FIG.
The voltage V from the DC power supply 12 is applied between the electrodes D and C. X is applied to the first input terminal Vi0 of the A / D conversion circuit 13.
By connecting the transparent electrode 3 to the measuring electrode B, the input position P
And the voltage between the electrode C is input. As a result, the A / D conversion circuit 13 converts the voltage between the input position P and the electrode C into a digital signal, and outputs it to the control circuit 14 as the Y-axis coordinate position of the input position P.

The control circuit 14 detects the position information of the input position P from the X-axis coordinate position and the Y-axis coordinate position obtained by time division. At this time, as shown in FIG. 8, according to the key arrangement displayed on the LCD 6, the control circuit 14 judges that a key input corresponding to the input position P has been made, and executes a predetermined key input process.

In such a basic operation, the input position P
Since the voltage value at one point is measured, there is a problem that the output coordinates fluctuate due to noise due to static electricity or the like, and inappropriate coordinates (jumped coordinates) apart from the input position P are acquired.

Therefore, in the present invention, as shown in FIG.
The X-axis and Y-axis voltage signals input to the A / D conversion circuit 13 are sampled to obtain n (here, P1 to P5
5) temporary coordinate positions are obtained, each temporary coordinate position is compared with the previous coordinate position, and the temporary coordinate position having an intermediate value between the two is determined as the true coordinate position. Characterize. Hereinafter, a specific description will be given with reference to FIGS. 4 to 6.

FIG. 4 is a flow chart for explaining the operation of the coordinate determination process executed by the CPU 21 in the control circuit 14. FIG. 5 is a diagram for explaining a changing state of output coordinates. In FIG. 5, P1 to P5 indicate a plurality of temporary coordinate positions obtained by sampling the voltage signal as described in FIG. Further, Pa indicates the previous coordinate position. FIG. 6 is a diagram showing the relationship between the distances between the temporary coordinate positions P1 to P5 and the previous coordinate position Pa. Here, the temporary coordinate positions P1 to P5 are arranged in ascending order of the distance from the previous coordinate position Pa.
Are lined up.

As shown in the flow chart of FIG.
By setting the sampling number of the A / D conversion circuit 13 by the control signal SA, the U21 sequentially reads the temporary coordinate positions P1 to P5 for the designated position from the A / D conversion circuit 13 and stores them in the register group 22. Yes (step S1).

Here, the previous coordinate position Pa has already been stored in the register 23, and the CPU 21 stores this coordinate position Pa and the temporary coordinate positions P1 to P stored in the register group 22.
5 by calculating the distances from each (step S
2) As shown in FIG. 6, the temporary coordinate positions P1 to P5 are arranged in ascending order of distance (step S3). Here, P
The order is 1, P4, P2, P3, P5. As a result, C
The PU 21 has a tentative coordinate position P in which the distance between the two is intermediate.
2 is selected and output to the outside (main body system) as a true coordinate position, and the coordinate position is stored in the register 23 as the next preparation (step S4).

As described above, a plurality of temporary coordinate positions with respect to the designated position are taken, and the temporary coordinate position having an intermediate value with respect to the previous coordinate position is set as the true coordinate position. In this case, there is a method of taking the average value of the distance between each temporary coordinate position and the previous coordinate position, but this method includes jump coordinates, and there is a drawback that accurate position information cannot be obtained. is there. On the other hand, in the present invention, the provisional coordinate position having the intermediate value of the distance from the previous coordinate position is selected from the provisional coordinate positions as the true coordinate position. If there are as few as two, jump coordinates may be selected, but more temporary coordinate positions are taken and the distance from the previous coordinate position has an intermediate value. If the temporary coordinate position is selected, it is highly possible that the jump coordinates can be eliminated, and as a result, stable position information can be obtained.

[0027]

As described above, according to the present invention, in a position information input device using a tablet, a plurality of temporary coordinate positions with respect to a designated position are taken, and among them, the distance from the previous coordinate position has an intermediate value. By setting the provisional coordinate position to be a true coordinate position, it is possible to eliminate inappropriate coordinates, that is, jump coordinates caused by fluctuations in output coordinates, and always obtain stable position information.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a position information input device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing details of a main part of FIG.

FIG. 3 is a diagram for explaining a method of acquiring a temporary coordinate position according to the embodiment.

FIG. 4 is a flowchart for explaining the operation of the coordinate determination process of the same embodiment.

FIG. 5 is a diagram for explaining a changing state of output coordinates of the embodiment.

FIG. 6 is a diagram showing a distance relationship between a temporary coordinate position and a previous coordinate position of the embodiment.

FIG. 7 is a conceptual diagram for explaining the operation of the apparatus of the same embodiment.

FIG. 8 is a conceptual diagram for explaining the structure of a touch panel.

[Explanation of symbols]

3 ... X-axis transparent electrode, 4 ... Y-axis transparent electrode, 10 ... Touch panel, 12 ... DC power supply, 13 ... A / D conversion circuit, 14 ...
Control circuit, 21 ... CPU, 22 ... Register group, 23 ... Register.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yoshihide Uchida 2-9 Suehiro-cho, Ome-shi, Tokyo Toshiba Personal System Engineering Co., Ltd. In-house

Claims (2)

[Claims] 1. A tablet means for outputting a voltage signal corresponding to each of an X-coordinate position and a Y-coordinate position of a designated position, and the voltage signal outputted by the tablet means is sampled to obtain a predetermined number of points for the designated position. Temporary coordinate acquisition means for obtaining the temporary coordinate position, distance calculation means for calculating the distance between each of the temporary coordinate positions obtained by this temporary coordinate acquisition means and the previous coordinate position, and the result of this distance calculation means Accordingly, a provisional coordinate position determining unit is provided which selects a provisional coordinate position having an intermediate distance between the two provisional coordinate positions and determines this as a true coordinate position with respect to the designated position. Position information input device. 2. A voltage signal corresponding to each of the X coordinate position and the Y coordinate position of a designated position is sampled to obtain a predetermined number of temporary coordinate positions for the designated position, and each temporary coordinate position and the previous A position information input method, which calculates a distance from a coordinate position, and determines a temporary coordinate position having an intermediate distance between them as a true coordinate position with respect to the designated position.