JPH08241161A - Touch panel device - Google Patents

Abstract

PURPOSE: To prevent malfunction due to multipoint simultaneous depression on an analog touch panel. CONSTITUTION: This device is equipped with a touch panel control part 11, an LCD module 12, an X-directional touch panel 13 which has a resistance film extended between one group of terminals, a Y-directional touch panel 14 which has a resistance film extended between one group of terminals crossing the extension direction of the resistance film of the X-directional touch panel, switches 15a-15f which switch supply voltages and detection potentials to between the terminals of the touch panels 13 and 14, and sense amplifiers 16a-16d which detect potentials outputted in response to the supply voltages to between the terminals of the touch panels 13 and 14. The input control part 24 of the touch panel control part 11 controls the respective switches, sense amplifiers, etc., to detect resistance value variation between the terminals of the touch panels 13 and 14, and compares the detected values with a specific reference value to detect the possibility that plural points are pressed. When the multipoint depression is detected, a depression candidate point is further detected and displayed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to printers, plotters,
The present invention relates to an analog type touch panel device used as an operation panel for various devices such as FAX and copy.

[0002]

2. Description of the Related Art A so-called analog touch panel is often used for a display / operation panel of many electronic devices (for example, copying machines, office equipment such as FAX, bank cash card dispensers, etc.) which are widely used today. This analog touch panel is disclosed in, for example, JP-A-4-36451.
As disclosed in Japanese Patent Laid-Open No. 2 (1994), the coordinate position is calculated by applying a DC voltage across the resistive film and detecting the potential at the pressed position on the resistive film. This analog touch panel system is a digital system. Compared with this, there is an advantage that the resolution of coordinate detection can be increased.

However, this analog touch panel has no means for detecting such a state when a plurality of points on the panel are pressed at the same time.
There is a possibility that the pressed position information may be collected by mistake.

[0004]

As described above, in the conventional analog touch panel, when a plurality of points on the panel are pressed, the position information detection method detects position information different from the pressed position (specifically, In some cases, the midpoint between the two points pressed on the panel), and as a result, an operation contrary to the operator's intention may be recognized. For this reason, measures have been taken to avoid erroneous operations, mainly by devising the screen design, such as the configuration of the operation screen and the allocation of switch functions.

However, even if such a measure is taken, it is difficult to completely eliminate a user's erroneous operation, and in any case, it is not possible to detect the state of pressing a plurality of points on the analog touch panel. It could not be an effective countermeasure. In addition, in some cases, it is not always easy for the user to use, because there is no choice but to set restrictions on the panel operation. Therefore, the present invention provides a touch panel device capable of avoiding erroneous data acquisition due to an erroneous operation of pressing a plurality of points on an analog touch panel and improving the operability by presenting candidates of pressed points to the operator. The purpose is to do.

[0006]

According to a first aspect of the present invention, there is provided an X-direction touch panel having a resistance film extending between a pair of terminals facing each other, and an X-direction touch panel disposed so as to be superposed on the X-direction touch panel. Directional touch panel, a Y-direction touch panel having a resistance film extending between a pair of terminals facing each other in a direction orthogonal to the extension direction of the resistance film, and switching means for switching a supply signal and a detection signal between the terminals of each touch panel. A detecting means for detecting a signal output in response to a signal supplied between terminals of each touch panel; a calculating means for calculating coordinates based on the signal detected by the detecting means; The change of the resistance value between the terminals of each touch panel by controlling the execution steps of the calculating means and the calculating means, and comparing the detected value with a predetermined reference value, Multiple point press detection means for detecting whether or not there is a possibility of multiple point presses, and when the possibility of multiple point presses on the panel is detected by this multiple point press detection means, the candidate points of the pressed points are detected. And a candidate point detecting means for achieving the above object.

According to a second aspect of the present invention, the touch panel device according to the first aspect is further provided with display means for displaying candidates of the pressed points detected by the candidate detection means, thereby achieving the above object. In the invention according to claim 3, in the touch panel device according to claim 1 or 2, further, the candidate points detected by the candidate point detecting means are compared and evaluated with the occupied area of the key switch displayed on the touch panel,
The determination means for determining the corresponding key switch as the pressed key switch is provided to achieve the above object.

[0008]

In the touch panel device according to the present invention, the change of the resistance value between the terminals of each touch panel is detected by controlling the execution steps of the switching means, the detecting means and the calculating means, and the detected value is a predetermined reference value. The presence or absence of the possibility of pressing a plurality of points on the panel is detected by comparison with. Then, when the possibility of pressing a plurality of points on the panel is detected, candidate points of the pressed points are detected.

In the touch panel device according to the second aspect, the detected candidates for the pressed point are further specifically displayed.
In the touch panel device according to the third aspect, the detected candidate point is further compared and evaluated with the key switch occupation area displayed on the touch panel, and the corresponding key switch is determined to be the pressed key switch.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the touch panel device of the present invention will be described in detail with reference to FIGS. FIG. 1 shows a functional configuration of a touch panel device according to an embodiment of the present invention. This touch panel device includes a touch panel controller 11 for controlling the entire device, an LCD module 12 for displaying necessary information, and an LC module 12 for displaying the necessary information.
1 provided on the D module 12 and facing each other
An X-direction touch panel 13 having a resistance film extended between the pair of terminals (X1, X2). Further, the touch panel device is provided on the X-direction touch panel and has a pair of terminals (Y1, Y1) facing each other in a direction orthogonal to the extending direction of the resistive film of the X-direction touch panel.
A Y-direction touch panel 14 with extending a resistor film between the 2), a switch 15 _a to 15 _f for switching both touch panel is applied between the terminals of detecting from (or terminal) signal line, a signal providing a sense amplifier 16 _a ~ 16 _d for sensing a separate detection circuit 17 for detecting that the touch panel surface is depressed, the bias required to measure the inter-terminal resistance value of the two touch panels And a bias resistance circuit 18.

The X-direction touch panel 13 and the Y-direction touch panel 14 are analog touch panels constructed by bonding respective resistance films, and detect the touch wherever the human finger or the like touches the touch-sensitive surface. You can do it.

[0012] Switch 15 one end of _a is connected to the + 5V power supply and the other end terminals X1 in the X-direction touch panel 14, a bias resistor circuit 18 and sense amplifier 16 switch 15 via a resistor R _X is connected to _{a e} Is connected to one end of. The other end of the switch 15 _e is connected to the + 5V power supply. One end of the switch 15 _b is grounded,
The other end is connected to the terminal X2 of the X-direction touch panel 14, and the bias resistance circuit 18 and the sense amplifier 16 are connected.
connected to _b . One end of the switch 15 _c is connected to the + 5V power supply and the other end terminal Y of the Y-direction touch panel 13
1, and is connected to the bias resistor circuit 18 and the sense amplifier 16 _c, and is also connected to one end of the switch 15 _f via the resistor R _Y. The other end of switch 15 _f is + 5V
Connected to power supply. Also, one end of the switch 15 _d is grounded and the other end is the terminal Y of the Y-direction touch panel 13.
2 and the bias resistor circuit 18 and the sense amplifier 16 _d .

The touch panel control section 11 includes an LCD controller 21 for controlling the screen of the LCD module 12,
A sense amplifier 16 _a ~ 16 _d alternatively switchable switch 22 the output of this is connected to the output terminal of the switch 22, converts the sensed voltage value into digital data A /
D converter 23, pressing detection switch 15 _a to 15
_An input control unit 24 that switches the terminal signal of the touch panel by switching _f and calculates coordinate data, and a main controller 25 that controls the input control unit 24 and the LCD controller 21 are provided. In this device, the input control unit 24 is realized by a microcontroller. The touch panel device is connected to a control unit (not shown) of the main body (for example, a copying machine) via serial and parallel communication lines.

Next, the operation of the touch panel device having the above structure will be described with reference to FIGS. 2 and 3. First,
A sequence at the time of collecting the initial data will be described with reference to FIG. Input control unit 2 at device initialization (immediately after reset)
4, as shown in FIG. 2, only the switches _15a and _15b are turned on (step 101), and the X-direction touch panel 1
A DC voltage is applied to the resistance film of No. 4 (hereinafter referred to as the X-direction resistance film). Equivalent circuit at this time is as shown in FIG. 4, the potential at the position of the terminal X1, X2 resistance values and the switch 15 _a of the X-axis resistor film, 15 _b is determined by the DC resistance component having respectively. In this state, the input controller 24 causes the switch 22 to sense the amplifiers 16 _a and 16 _b.
Is input to the A / D converter 23, and the potentials at the positions of the terminals X1 and X2 are collected as initial data V _X1 and V _X2 (step 102).

Next, the input control section 24 uses the switch 1
Only _5c and _15d are turned on (step 103), and Y
A DC voltage is applied to the resistance film of the directional touch panel 13 (hereinafter referred to as the Y-direction resistance film), and the input of the sense amplifiers 16 _c and 16 _d is switched by the switch 22 as in the case of the X direction, thereby the A / D converter. 23 and input to terminals Y1 and Y
The potential at the position ₂ is collected as initial data V _Y1 and V _Y2 (step 104).

Further, the input control section 24 includes a switch 1
5 _e, 15 _b only is turned on (step S105),
It is connected to a circuit for measuring the resistance value of the X-direction resistance film. Thus, the voltage value V _RX determined by the resistance values of the resistor R _X and the X-direction resistance film is measured (step 10).
6), this value becomes a parameter indicating the initial value of the X-direction resistance film. Similarly, the input control unit 24 uses the switches 15 _f , 1
Only _5d is turned on (step 107) and connected to a circuit for measuring the resistance value of the Y-direction resistance film. As a result, the voltage value _VRY determined by R _Y and the resistance value of the Y-direction resistance film is measured (step 108), and this value becomes a parameter indicating the initial value of the Y-direction resistance film.

Note that such a sequence of initial data collection is carried out periodically, and by always maintaining the latest reference value, it is possible to cope with changes in ambient environment conditions. Further, the reference data collected periodically is compared and evaluated with the initial value stored at the time of initialization, and the one with a large difference is removed. The initial data is updated by operating a switch or the like as necessary, and stored in a non-volatile data holding means (for example, EEPROM or the like).

Next, the sequence during normal operation will be described with reference to FIG. First, after the initial data collection completion, the input control unit 24 turns off the to turn on only the switch 15 _a switch 15 _b to 15 _f. When the touch panel is pressed in this state, a voltage of about 5 V is detected by the sense amplifier 16 _d . This result is detected by the detection circuit 17 and notified to the input control unit 24. As a result, the input control unit 2
4 recognizes pressing of the touch panel.

Next, the input control section 24 is connected to a circuit for measuring the resistance values of the X-direction resistance film and the Y-direction resistance film in the order shown in FIG. First, for the X direction, only the switches _15e and _15b are turned on (step 20).
1), a voltage value indicating the inter-terminal resistance value (RTP _X ) of the X-direction resistance film is obtained (step 202). At this time, when one point on the panel is pressed, the resistance value between terminals of the resistance film becomes the same value as the initial value, but when two points on the panel are pressed, the equivalent circuit is shown in FIG. Like That is, between the touch points A and C of the touch panel, the resistance component of the Y-direction resistance film (R _TPY ) is connected in parallel to the resistance component of the X-direction resistance film (R _TPX ). Therefore, the resistance value RTP _X between terminals in the X direction decreases.

The input controller 24 compares and evaluates the measured voltage value indicating the resistance value of the X-direction resistance film with the reference voltage value V _RX , calculates the difference V _dX , and temporarily holds it (step 2).
03). The same resistance value detection process is performed on the Y-direction resistance film, and the difference V _dY between the voltage value indicating the resistance value of the Y-direction resistance film and the reference voltage value V _RY is obtained (step 2).
04-206). In this way, when the collection of the difference data V _dX and V _dY indicating the difference resistance value between the terminal resistance values of the X-direction resistance film and the Y-direction resistance film with respect to the reference resistance value is completed, the input control unit 24 next Move to the position data collection sequence. That is, the pressed position data in each of the X / Y directions is collected by the procedure shown in steps S207 to S211.

The voltages collected here are V _Xm and V _Ym (FIG. 4)
When the X and Y coordinate axes are represented by 0 to 255, the coordinate positions in the X direction and the Y direction can be represented by the following equations 1 and 2.

[0022]

[Formula 1] X coordinate = 255 × (V _Xm −V _X2 ) / (V _X1 −V _X2 ).

[0023]

[Formula 2] Y coordinate = 255 × (V _Ym −V _Y2 ) / (V _Y1 −V _Y2 ).

Next, the input control section 24 evaluates the difference data V _dX and V _dY in order to determine whether or not a plurality of points have been pressed. If V _dX and V _dY are equal to or less than the predetermined values V _dt and V _dt (step 212; N), it is determined that the single point is pressed (step 213), and the equations (1) and (2) are used. The X-coordinate and Y-coordinate obtained in step 3 are used as they are as input coordinates. On the other hand, when the difference data V _dX and V _dY exceed V _dt and V _dt (step 212; Y), it is determined that a plurality of points have been pressed, and the processing for estimating the next pressed point is executed (step 21).
4). The principle of pressing point estimation is as follows.

That is, as shown in FIG. 5 and FIG.
When multiple points (here, points A and C) are pressed, X
The resistance value RTPX 'of the directional resistance film can be expressed by the following equation (3).

[0026]

(3) RTP _X ′ = RTP _X −R _TPX + 1 / (1 / R
_TPX + 1 / R _TPY )

Further, since the X- and Y-direction resistance films have a predetermined linearity, the Y-direction resistance value R _TPY of the parallel resistance portions is expressed by the following equation (4).

[0028]

[ _Equation 4] R _TPY = R _TPX × (RTP _Y / RTP _X ) × A

Here, A is the X of the touch panel effective operation surface.
It is a constant determined by the Y diagonal ratio. From the equations (3) and (4), the resistance change of the X-direction resistance film when a plurality of points are pressed is expressed by a function of the resistance value in the X-direction (here, R _TPX ) in the range of parallel resistance. Therefore, from the difference data V _dX indicating the change in the resistance value, the resistance value R in the X direction in the range of the parallel resistance.
_{The TPX} can be calculated. Furthermore, since the linearity of the resistance film is ensured, the physical length in the X direction (X ′ shown in FIG. 6) of the range of parallel resistance can be obtained. Similarly, the physical length Y ′ in the Y direction of the range of parallel resistance can be obtained.

On the other hand, in the depressed state as shown in FIGS. 5 and 6, the coordinate data collected in steps S207 to S211 of FIG. 3 indicates the midpoint M of the two depressed points (A, C). . Therefore, from the coordinate data of the midpoint M and the physical lengths X'and Y'in the X and Y directions of the range of parallel resistance, the candidates (A, B, C, D) of the pressed point coordinates are obtained. Can be estimated.

Candidates (A,
B, C, D), the center coordinates (and the key input determination area) of the key switch displayed on the panel are compared and evaluated, and the corresponding one is determined as the pressed key. When there are a plurality of keys as applicable candidates, priority may be given depending on the key position or blinking may be performed.

[0032]

As described above, according to the first aspect of the present invention, the touch panel device according to the present invention detects a change in the resistance value between the terminals of each touch panel and uses the detected value as a predetermined reference. Compared with the value, it detects whether there is a possibility of pressing multiple points on the panel, and when it detects the possibility of pressing multiple points on the panel, it detects the candidate point of that pressing point. It is possible to prevent malfunction due to. Furthermore, when multiple point presses are detected, it is possible not only to remove the input data but also to accept the operation depending on the conditions, and it is possible to reduce the operational restrictions for the user, thus improving the operability. Can be planned. In the touch panel device according to claim 2, further, since the detected candidates for the pressed point are concretely displayed, the user can concretely and visually know his / her erroneous operation, and should perform it next. It becomes easy to properly judge the operation. In the touch panel device according to claim 3, further, the detected candidate point is compared and evaluated with the key switch occupation area displayed on the touch panel, and the corresponding key switch is determined to be the pressed key switch. Therefore, in some cases, the input data by the operation already performed is adopted as valid data without performing the re-operation again.

[Brief description of drawings]

FIG. 1 is a block diagram showing a functional configuration of a touch panel device according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining an operation of the touch panel device of FIG. 1 when collecting initial data.

FIG. 3 is a flow chart diagram for explaining the operation of the touch panel device of FIG. 1 during normal coordinate data collection.

FIG. 4 is a diagram showing an equivalent circuit at the time of collecting initial data.

FIG. 5 is a diagram showing an equivalent circuit when two points are pressed.

FIG. 6 is a diagram illustrating candidates of pressed point coordinates when two points are pressed.

[Explanation of symbols]

11 Touch Panel Control Section 12 LCD Module 13 Y Direction Touch Panel 14 X Direction Touch Panel 15 _a to 15 _f Switch 16 _{a to} 16 _d Sense Amplifier 17 Detection Circuit 18 Bias Resistor Circuit 21 LCD Controller 22 Switcher 23 A / D Converter 24 Input Control Section 25 Main controller

Claims (3)

[Claims] 1. An X-direction touch panel having a resistance film extending between a pair of terminals facing each other, and an X-direction touch panel disposed so as to be superposed on the X-direction touch panel.
Directional touch panel, a Y-direction touch panel having a resistive film extending between a pair of terminals facing each other in a direction orthogonal to the extending direction of the resistive film, and switching means for switching a supply signal and a detection signal between the terminals of each touch panel. A detecting means for detecting a signal output in response to a signal supplied between terminals of each touch panel; a calculating means for calculating coordinates based on the signal detected by the detecting means; Whether or not there is a possibility of pressing multiple points on the panel by controlling the execution steps of the control means and the arithmetic means to detect a change in resistance value between terminals of each touch panel and comparing the detected value with a predetermined reference value. Detecting means for detecting a plurality of points, and when the possibility of pressing a plurality of points on the panel is detected by the means for detecting a plurality of points, the candidate points of the pressing points are detected. The touch panel apparatus being characterized in that comprising a complement point detection means. 2. The touch panel device according to claim 1, further comprising display means for displaying candidates of the pressed points detected by the candidate detection means. 3. The determination means for comparing and evaluating the candidate point detected by the candidate point detection means with the occupied area of the key switch displayed on the touch panel, and determining the corresponding key switch as the pressed key switch. The touch panel device according to claim 1, wherein the touch panel device is provided.