JPH0281221A - Touch panel input device - Google Patents

Abstract

PURPOSE:To constitute the title device so that position data is not outputted when it comes into contact carelessly with the surface of a display by detecting the case for designating a designated position on the display extending over at least two times by placing a no-touch period between. CONSTITUTION:In case of inputting necessary information of a screen displayed on a display device, for instance, the same part is designated two times. In this case, a first touch and a second touch are detected by the respective detecting means 5, 7 by placing a no-touch period between. In such a case, a position data output means 8 compares the respective position data, and when they are almost the same data, its data are outputted as position data which is brought to touch input. In such a way, even if a screen displayed on the display device is pointed to with a finger or touched caselessly, designated position data comes not to be outputted except the case of inputting necessary information.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an optical touch panel input device using a light beam such as an infrared beam.
It is installed around a display such as R'T', and when a specific position on the display is specified with an obstacle such as a finger,
The present invention relates to a touch panel input device that allows the specified position to be input to a computer, etc.

<Prior art> An optical touch panel input device that uses a light beam works in conjunction with various images and information displayed on a CRT.
It is a device that allows you to easily input various data by touching the screen at a specific position on the R'T' with your finger.
It is becoming widely used as an interface with computers.

Conventionally, as this type of touch panel input device, there is a device as disclosed in US Pat. No. 3,775,560, for example.

FIGS. 4 and 5 are conceptual diagrams showing the configuration of the device disclosed herein.

In these figures, 1 is a display device, 2
1 to 2n are a plurality of light sources arranged on two sides of the display device 1, and 31 to 3n are a plurality of light sources arranged on the remaining two sides of the display device 1 so as to face the plurality of light sources 21 to 2n. It is a light receiving element. These plurality of light sources and light receiving elements are arranged in the mounting block 10 and configured so that the light beam emitted from the light source passes over the surface of the display device 1.

The output signals of the plurality of light receiving elements 31 to 3n are applied to the position detecting means 41.42 via the scanning means SWI, SW2, and the timing at which the amplitude of the signal from the light receiving elements changes is detected. The position specified by a finger or the like on the spray device 1 is known.

<Problem to be solved by the invention> By the way, the touch panel input device having such a configuration has the following problems:
It detects whether or not the light beam passing over the display device is obstructed, and has the advantage of high detection sensitivity.However, on the other hand, it can also be detected if the display device is touched carelessly or an insect crosses over it. There is a problem with detecting.

The present invention was made in view of these problems, and its purpose is to prevent necessary information from being displayed even if the screen displayed on the display device is pointed with a finger or touched carelessly. The object of the present invention is to realize a touch panel input device that does not output specified position data except when inputting the specified position data.

Means for Solving the Problems> FIG. 1 is a block diagram showing the basic configuration of the present invention.

In the figure, 5 is a first touch position detection means that sequentially inputs signals from a plurality of light receiving elements 31 to 3n and detects a position signal caused by the first touch from the timing when the amplitude changes; 6 is a first touch position detection means; No-touch period detection means for detecting whether there is a no-touch period after the touch of 7
8 is a second touch position detection means that sequentially inputs signals from a plurality of light receiving elements after a no-touch period and detects a position signal due to a second touch from the timing when the amplitude changes; 8 is a first and second touch position detection means; The position data output means compares at least two pieces of position data obtained by the second touch position detection means and outputs the position data as position detection data when the two or more pieces of position data are approximately the same.

Effect> When inputting necessary information on a screen displayed on a display device, it is assumed that, for example, the same location is specified twice. In this case, the first touch and the second touch are detected by the respective detection means with the no-touch period in between.

At this time, the respective position data are compared, and if the data are almost the same, the data is output as the position data input by touch.

<Example> Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a configuration block diagram showing one embodiment of the present invention. In FIG. 0, 1 is a display device, 21x
~2nx, 21y~2ny is display device 1
Multiple light sources arranged on two sides of , 31x to 3nx, 3
1y to 3ny are a plurality of light sources 21x to 2nx, 214 to 2
A plurality of light receiving elements are arranged on the remaining two sides of the display array device 1 so as to face ny.

These multiple light sources and light receiving elements are configured such that the light beam emitted from the light source passes over the surface of the display device 1 as shown by the broken line.

11 is a selector that sequentially selects the output signals of the plurality of light receiving elements 31'x to 3nx; 12 is a sample/hold circuit that samples and holds the signal from the light receiving element selected by the selector 11; and 13 is an A/D conversion circuit. A microprocessor 14 inputs the signal from the sample/hold circuit 12 via an A/D converter 13. 15
is memory coupled to microprocessor 14.

The microprocessor 14 includes a drive circuit R (not shown) for a plurality of light sources, a selector 11, and a sample/hold circuit 12.
In addition, the program stored in the memory 15 functions as each of the detection means 5, 6, 7 and the position data output means 8 in FIG.

In addition, in this figure, a plurality of light receiving elements 31 lined up in the Y-axis direction
Although omitted, the signal processing circuits from y to 3ny are the same as the signal processing circuits for the plurality of light receiving elements lined up in the X-axis direction.

The operation of the device configured in this way will be described next.

FIG. 3 is a flowchart showing an example of the operation performed by the microprocessor 14.

First, the microprocessor 14 sets an internal light-receiving element number counter to "1" (step 1).
) 0 Next, drive the selector 11 to select the first light receiving element 3.
The received output voltage V31x from 1X is read through the sample/hold circuit 12 and A/D converter 13 (step 2).

Next, the magnitude of the read reception output voltage V31x is
It is determined whether the predetermined set voltage vth is larger than a predetermined set voltage vth (step 3). Here, the predetermined set voltage vth is determined by determining whether there is no obstacle in the optical path of the light beam crossing the display 1 or not. It is determined from the difference in received output voltage between the two cases, and is determined, for example, by equation (1).

Vth=1/2・(Vno-Vc)...(1) However, Vno is the received output voltage when there is no obstacle in the optical path of the light beam, and Vc is the received output voltage when there is an obstacle in the optical path of the light beam. In the received output voltage step 3, if V31x≦vth, it is determined that there is a touch and the process branches to step 13.

In addition, in step 3, if V31 It is determined whether the number after a (in this case, 40 are arranged) has been reached, and if the last number has not been reached, the process returns to step 2 (step 5).

In the branched step 14, it is determined whether the value of the touch number counter is "1", and if not, the value N1 of the light receiving element number counter is stored in the memory 15 as the first touch position data (step 15). The touch count counter is set to "1" (step 16), and the process returns to step 4.

In step 5, it is determined whether the same procedure has been performed for the output voltages up to the last number "40" of the light receiving element number, that is, whether the value of the receiving element number counter has reached the last number "40", and it is judged as Yes. If so, proceed to Step 6, and in Step 6 and Step 7, check whether there is a first or second touch (“1” in the touch counter).
If it is determined that there is a first touch but not a second touch, the process moves to step 8.

Steps 2 to 6 so far, Stella 114~
The operation up to step 16 is the first touch detection means 5.
This is equivalent to performing the operations as follows.

When it is determined that the first touch is present and the second touch is not, the process moves to step 8, where the value of the light receiving element number counter is set to "1", and the no-touch period detection means 6
Steps 9 to 13 are executed. In these steps, it is determined whether there is a period in which the display 1 is not touched by determining whether the output voltages from all the light receiving elements are Vix>Vth. That is, if all the signals from the plurality of light receiving elements are higher than the set voltage vth, the process moves to step 13, sets a no-touch flag indicating that there is a no-touch period (sets "1"), and returns to step 1.

In step 3, it is detected whether there is a touch, and in step 14, if r14 is set in the touch counter, the process moves to step 17, where it is determined whether the no-touch flag is "1". is detected, and then a no-touch period is detected, the process moves to step 18, and fiiN2 of the receiving element number counter is
It is stored in the memory 15 as the second touch position data, and then "2" is set in the touch number counter (
Step 19), steps 1 to 5, steps 14, and steps 17 to 19 operate as a second touch detection means.

In step 7, if it is determined that there is a second touch, the process moves to step 20, where from the memory 15,
The first position data N1 and the second position data N2 stored in steps 15 and 18 are read out, and it is determined whether N1=N2. As a result, it is determined that the same position on the display 1 has been designated twice in a row (determined to be a correct position designation), and this position data N1 or N2 is output as correct data for position designation.

In addition, in the above explanation, the first position data N1 and the second position data N2 were explained as being equal, but assuming that the position is specified by an obstacle such as a finger, they may not necessarily be the same position. Since it is not always possible to specify it twice, it is actually desirable to provide some tolerance range when comparing N1 and N2. In this case, the position data output in step 21 also has to be specified twice. The average value of the data may be output as position data.

Further, in this example, it is assumed that the specified position on the display is specified twice, but it may be specified, for example, three times.

In addition, in step 3 or step 10, the determination of whether or not there is a touch is made by comparing the output voltage from the light-receiving element read sequentially with a predetermined set voltage vth. It may be changed in consideration of variations in characteristics of the elements and light source elements, and deterioration of characteristics.

In addition, in the above explanation, a step is provided before step 2 to measure the output voltage vb from the light receiving element in a state where the light source is not driven (a state in which no light beam is emitted), and from the output voltage Vix read in step 2. Subtract the output voltage vb, and calculate this subtraction result (Vix-Vb) and the set voltage v
By providing such a step, even if there is extraneous light other than the light beam from the light source, the presence or absence of a touch can be accurately detected without being affected by this extraneous light. It becomes possible to do so.

<Effects of the Invention> As explained in detail above, the present invention detects the case where a specified position on the display is specified at least twice with a no-touch period in between. If you unconsciously point your finger at the display or accidentally touch it while trying to remove dust, position data will not be output.

Therefore, according to the present invention, a highly reliable touch/screen input device can be provided.

[Brief explanation of the drawing]

Figure 1 is a block diagram showing the basic configuration of the present invention, Figure 2 is a block diagram showing the basic configuration of the present invention.
FIG. 3 is a block diagram showing an embodiment of the present invention, FIG. 3 is a flowchart showing the operation, and FIGS. 4 and 5 are conceptual diagrams of the structure of a conventional device. 1... Display, 21x to 2nx, 21y to 2ny... Light source element, 31
x~3nx, 31y~3ny...light receiving element, 5...
1st touch detection means, 6... no-touch period detection means, 7... 2nd touch detection means,

Claims (1)

[Scope of Claims] First touch position detection means that sequentially inputs signals from a plurality of light receiving elements and detects a position signal caused by the first touch from the timing at which the amplitude changes; a no-touch period detection means for detecting whether there is a no-touch period after the no-touch period; and sequentially inputting signals from the plurality of light receiving elements after the no-touch period;
second touch position detection means for detecting a position signal due to the second touch from the timing at which the amplitude changes; and at least two or more position data obtained by the first and second touch position detection means. A touch panel input device comprising: position data output means for comparing the position data and outputting the position data as position detection data when the respective values are substantially the same.