JP2022136389A - Touch panel device and display device using the same - Google Patents

Abstract

To provide a touch panel device capable of identifying a touch such as a long press.SOLUTION: A touch panel device 100 of the present invention includes a touch panel 110 and a controller 120 that scans the touch panel 110 and detects a touch based on sensing signals obtained by the scanning. The controller 120 calculates a change amount ▵T between the sensing signal of the previous frame and the sensing signal of the current frame, performs this calculation over a plurality of frame intervals, calculates an integrated value ▵c (▵c=▵T1+▵T2+▵T3, ..., ▵Tn-1) of the obtained plurality of change amounts (▵T1, ▵T2, ▵T3, ..., ▵Tn-1), and identifies the sensing signals as a long press touch when the integrated value ▵c is equal to or greater than a long press detection threshold Th_U.SELECTED DRAWING: Figure 6

Description

The present invention relates to a touch panel device that detects touch operations, and more particularly to detection of long presses.

A touch panel is integrated with a liquid crystal display or the like in a display unit and used as an input interface for receiving a touch operation or the like from a user. A resistive film system and a capacitive system are widely used for touch panels. The capacitive touch panel includes a surface capacitive type, a projected capacitive type, and the like.

FIG. 1 shows a schematic plan view of a projected capacitive touch panel (Patent Document 1). The touch panel 6 has a touch sensor 11 . The touch sensor 11 includes an X-side line sensor 12 along the X-direction and a Y-side line sensor 13 along the Y-direction. The X-side line sensor 12 has a plurality of electrodes 14 along the X direction arranged in parallel and spaced apart in the Y direction, and the Y-side line sensor 13 has a plurality of electrodes 15 along the Y direction arranged in parallel and spaced apart in the X direction. do. In the mutual capacitance method, for example, the X-side line sensor 12 is sequentially scanned, and the Y-side line sensor 13 senses the capacitance at the intersection of the electrodes 14 and 15 .

Further, the touch panel device of Patent Document 2 determines whether or not the contact object is a foreign object based on a comparison between the measured value of the relative acceleration of the contact object and the theoretical value of the relative acceleration of the foreign object. determines that the change in capacitance is not caused by a user's operation but by a foreign object when a change in capacitance is detected and the proximity sensor does not detect the proximity of an object.

JP 2018-77755 A JP 2014-857717 A JP 2012-138026 A

In the capacitive touch panel device, as shown in FIG. 2A, the controller 20 performs scanning/sensing of the touch panel 10 and detects an operation such as a touch at a position where a change in capacitance occurs. , this detection method is based on whether the change in capacitance is caused by a long press of a human finger U as shown in FIG. There is a problem that it is difficult to identify whether it is occurring. Such a problem also occurs in a resistive touch panel.

Therefore, as shown in FIG. 3, the conventional detection algorithm scans the touch panel 30, measures the sensing signal obtained by scanning (S100), and if the sensing signal is greater than or equal to the touch detection threshold Th (S110). Next, it is determined whether the sensing signal is a continuous signal (S120), and if the continuous signal is within the timeout period (S130), the sensing signal is considered valid, and the touch position detected by the sensing signal is changed. Notify the user of the coordinates. On the other hand, if the continued signal exceeds the timeout period, the sense signal is considered invalid, the data (sense signal) is discarded, and the user is not notified of the touch position.

However, if such timeout processing is performed, for example, when a long press such as a fast-forward operation or scroll operation is performed for a long time, the touch operation is not detected due to the timeout processing in the middle of those operations. Scrolling stops, and the user is requested to re-operate, such as fast-forwarding, which reduces user convenience.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a touch panel device and a display device capable of solving the above-described conventional problems and distinguishing a touch such as a long press.

A touch panel device according to the present invention includes a touch panel and control means for scanning the touch panel and detecting a touch based on a sensing signal obtained by scanning, wherein the control means senses a previous frame. A change amount between a signal and a sensed signal in a current frame is calculated between a plurality of frames, an integrated value of the plurality of calculated change amounts is calculated, and whether or not there is a touch is identified based on the calculated integrated value.

In one aspect, the control means calculates a plurality of integrated values between a plurality of frames, and identifies whether or not there is a touch based on an average value of the plurality of integrated values. In one aspect, the control means further calculates the movement of the detection position based on the sensing signals of the plurality of frames, and identifies whether or not there is a touch based on the calculated movement of the detection position and the integrated value. In one aspect, the control means identifies whether the touch is a long press or not. In one aspect, the control means ends the calculation of the integrated value when the touch detection is canceled from the touch panel. In one aspect, the touch panel is a capacitive type or a resistive type.

According to the present invention, whether or not there is a touch is identified based on the integrated value of the amount of change in the sensed signal between frames in a plurality of frames. Touch can be detected accurately. This enables the user to perform continuous operations (long-press operations) such as fast-forwarding and scrolling, thereby improving user convenience.

1 is a schematic plan view of a capacitive touch panel; FIG. It is a figure explaining the subject of the conventional touchscreen device. FIG. 10 is a diagram showing an operation flow of a detection algorithm of a conventional touch panel device; It is a figure which shows the structure of the touch-panel apparatus based on the Example of this invention. FIG. 5A shows an example of the waveform of the sensing signal when the button is pressed for a long time, and FIG. 5B shows an example of the waveform of the sensing signal when an object is placed on the touch panel. FIG. 6(A) is a graph comparing the sensing signal when the long press is made and the sensing signal when the object is placed, and FIG. It is a graph comparing the integrated value of time. FIG. 5 is a diagram showing an example of an operation flow of a detection algorithm of the touch panel device according to the embodiment of the present invention;

Next, an embodiment of the invention will be described. A touch panel device according to the present invention includes a touch panel and detects a touch of an operation target (for example, a user's finger). Touch includes contact or proximity to the touch panel. The touch panel device according to the present invention may be either a capacitive touch panel or a resistive touch panel. Further, the touch panel device according to the present invention provides a display device or a display unit mounted on a display such as a liquid crystal panel and having a user interface function. Such display devices are used, for example, in in-vehicle devices, multifunctional mobile phones (smartphones), portable information terminals (tablet computers, laptop computers, notebook computers), and the like.

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 5 is a block diagram showing the configuration of the touch panel device according to this embodiment. The touch panel device 100 includes, for example, a capacitive touch panel 110 and a controller 120 that performs touch detection and the like on the touch panel 110 .

As shown in FIG. 1, the touch panel 110 has a substrate such as glass or plastic on which transparent electrodes 14 and 16 arranged in a matrix in the X and Y directions are arranged below an insulating film or the like. When the touch panel 110 is touched with a finger, the capacitance between electrodes in the vicinity thereof changes, and the touch position is detected by specifying the change in capacitance in the X-direction column and the Y-direction column. The touch panel 110 is mounted on, for example, a liquid crystal panel (not shown) and provides a user input interface for images displayed on the liquid crystal panel.

Controller 120 controls the overall operation of touch panel 110 . The controller 120 includes a drive circuit for sequentially scanning the electrodes 14 of the X-side line sensor 12 shown in FIG. 1 and a sense circuit for sequentially sensing the electrodes 15 of the Y-side line sensor 13. The sense circuit A sensing signal corresponding to the capacitance generated at the position where the electrodes 14 and 15 intersect (hereinafter referred to as sensing area) is measured. The controller 120 or sense circuit may include an amplifier circuit that amplifies the analog sensing signal depending on the capacitance of the sensing region, and an A/D converter that converts the amplified analog sensing signal to a digital sensing signal. Alternatively, the Y-side line sensor 13 may be used on the scanning side, and the X-side line sensor 12 may be used on the sensing side.

The controller 120 performs scanning/sensing of the entire sensing area of the touch panel 110 via the driving circuit/sense circuit every 2-3 milliseconds, for example. Here, a signal group of sensing signals, which are the measurement results of the entire sensing area of the touch panel 110, is called a frame. Therefore, one frame is generated every 2-3 milliseconds. Normally, the touch panel 110 is touched with a finger for at least several tens of milliseconds. If the generation of one frame is 3 milliseconds and the finger touch time is 30 milliseconds, 10 frames will be generated during the finger touch period. Also, if it is a long press, the touch period may be several seconds to several tens of seconds.

The controller 120 detects a touch based on the sensing signal of each frame. In one aspect, the controller 120 includes a microprocessor or microcontroller with ROM/RAM or the like, and performs touch detection algorithms by executing programs stored in the ROM/RAM.

Next, a method for identifying a long press in the touch panel device of this embodiment will be described. In a capacitive touch panel or a resistance touch panel, when a person operates (for example, a finger), slight movement occurs in the capacitance or resistance value. On the other hand, when an object is placed on the touch panel, minute changes in capacitance or resistance are very small. In this embodiment, it is possible to distinguish between human operation (especially long press) and other operations based on the fact that the behavior of sensing signals differs between human operation and object leaving.

FIG. 5A shows the waveform of the sensing signal when the capacitive touch panel 110 is touched with a human finger U, and FIG. 5B shows an object B placed on the capacitive touch panel 110 2 is the waveform of the sensed signal at a time, the waveform being for about 10 seconds. When the finger U is touched at time t1, in response to this, the level of the sensing signal exceeds the touch detection threshold Th, and after that, the level of the sensing signal is generally constant, but slight movement occurs. On the other hand, the level of the sensing signal exceeds the touch detection threshold Th in response to the touch of the object B at time t1, but there is almost no slight movement at this level. FIG. 6A is a graph schematically showing waveforms of actual sensing signals when a finger is long pressed (solid line) and an object is left untouched (dashed line).

The controller 120 calculates the amount of change between the level of the sensed signal in the previous frame and the level of the sensed signal in the current frame with respect to the sensed signal exceeding the touch detection threshold Th, and calculates such amount of change between a plurality of frames. , and the amount of change thereof is accumulated. , Tn of the sensing signals of frames F1, F2, . . . , Fn. Calculate T4=ΔT3, . . . , Tn-1-Tn=ΔTn-1. Then, the integrated value Δc=ΔT1+ΔT2+ΔT3, . . . +ΔTn-1 is calculated.

FIG. 6B is a graph showing a comparison between the integrated value Δc_U when the finger is long pressed and the integrated value Δc_B when the object is left untouched. The integrated value Δc_U of long-pressing of the finger becomes larger than the integrated value Δc_B of leaving the object as time passes (that is, the integrated number of changes between frames), and the difference between the two may gradually increase. Recognize.

Therefore, the controller 120 sets an appropriate long-press detection threshold Th_U based on the relationship shown in FIG. If the long-press detection threshold value Th_U, then the sensing signal is identified as being caused by the long-pressing of the finger, and if the integrated value Δc<the long-pressing detection threshold Th_U, the sensing signal is caused by something other than the long-pressing of the finger (for example, objects, etc.). In one aspect, the controller 120 may determine that the integrated value Δc≧long-press detection threshold Th_U at a time corresponding to the timeout time of the conventional detection algorithm (step 130 in FIG. 3). In other words, the integrated value Δc of the amount of change between frames is calculated for a plurality of frames buffered until the timeout occurs, and this integrated value Δc is compared with the long press detection threshold Th_U. In a certain aspect, regardless of the time-out period, the determination of integrated value Δc≧long-press detection threshold Th_U may be performed in a predetermined period of time or the number of frames. In one aspect, the integrated value Δc≧long-press detection threshold Th_U may be continuously determined until the sensing signal becomes less than the touch detection threshold th, that is, until the touch is released. Further, the integration of the amount of change between frames may be terminated when the touch is released, or may be terminated when the long press is identified by the determination that the integrated value Δc≧long press detection threshold Th_U. good.

Thus, according to this embodiment, it is possible to identify whether the finger has been long-pressed or an object has been placed, without using time-out processing as in the prior art, so that the user can fast forward. Continuous operation (long press operation) such as scroll movement is possible, and user convenience can be improved. Further, by accurately identifying the long press of the finger, it is possible to prevent malfunction (unintended calibration operation, etc.).

FIG. 7 is a flow showing an example of the detection algorithm of this embodiment. The controller 120 scans the touch panel 30, measures the sensing signal obtained by scanning (S100), and determines whether the sensing signal is equal to or greater than the touch detection threshold Th (S110). For example, as shown in FIG. 5A, when a finger U touches the touch panel 110, the capacitance of the touched sensing area changes, and a sensing signal exceeding the touch detection threshold Th is measured. The controller 120 identifies the touched sensing area from the X-direction column and the Y-direction column.

When the sensing signal is equal to or greater than the touch detection threshold Th, the controller 120 determines whether or not the sensing signal continues (S120). is performed between a plurality of frames, and it is determined that the integrated value Δc≧long-press detection threshold Th_U (S200). In one aspect, when the sensing signal is determined to be equal to or greater than the touch detection threshold th, the controller 120 buffers frames following the current frame in a FIFO memory or the like, and determines whether the sensing signal continues based on the buffered frames. is determined and the integrated value Δc is calculated.

The controller 120 calculates an integrated value Δc for a predetermined number of frames or a predetermined time period from touch detection, and if the calculated integrated value Δc is equal to or greater than the long-press detection threshold Th_U (S200), A change in capacitance is identified as a long finger press (S210), and the coordinate position of the detected touch is notified to the user (for example, the controller of the display device, etc.). On the other hand, if the calculated integrated value Δc is less than the long-press detection threshold Th_U (S200), the change in capacitance is identified as an object left unattended (S220), the data (sensing signal) is discarded, and the coordinate Do not notify the user of the location.

Next, a modified example of this embodiment will be described. In the above embodiment, the integrated value Δc is compared with the long-press detection threshold Th_U. A long press detection threshold Th_U may be compared. For example, the integrated value Δc_1 of each amount of change from frame 1 to frame 3, the integrated value Δc_2 of each amount of change from frame 4 to frame 6, and the integrated value Δc_3 of each amount of change from frame 7 to frame 9 are calculated. Then, the average value Δc_AV=(Δc_1+Δc_2+Δc_3)/3 is calculated, and Δc_AV≧long press detection threshold Th_U is determined. With such processing, it is sufficient for the buffer memory to store data for three frames, and the required memory capacity can be reduced.

Also, as another modification, the controller 120 may use the movement of the detected position during that time in addition to calculating the integrated value. When an object is left on the touch panel, the detected position does not change, but when a finger is touched, the detected position may move. A swipe operation such as scrolling causes movement at the detected position. Therefore, the controller 120 detects the touch position (the sensing area that generates the sensing signal equal to or greater than the touch detection threshold Th) based on the sensing signal of each frame, and calculates the movement or change amount ΔM of the detected touch position. The period (number of frames) for calculating the amount of change in the touch position may be the same as the period (number of frames) for calculating the integrated value, or may be shorter.

The controller 120, for example, (integrated value Δc+movement ΔM)≧long-press detection threshold Th_U or (integrated value Δc×movement ΔM)≧long-press detection threshold Th_U. By weighting with M, it is possible to easily determine the identification of a long press.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to specific embodiments, and various modifications, Change is possible.

12: X-side line sensor 13: Y-side line sensor 14, 15: Electrode 100: Touch panel device 110: Touch panel 120: Controller U: Finger B: Object

Claims (7)

A touch panel device including a touch panel and control means for scanning the touch panel and detecting a touch based on a sensing signal obtained by scanning,
The control means calculates an amount of change between a sensing signal of a previous frame and a sensing signal of a current frame between a plurality of frames, calculates an integrated value of the plurality of calculated amounts of change, and calculates the integrated value. A touch panel device that distinguishes whether or not there is a touch based on the touch panel. 2. The touch panel device according to claim 1, wherein said control means calculates a plurality of integrated values between a plurality of frames, and determines whether or not there is a touch based on an average value of said plurality of integrated values. 3. The controller according to claim 1, wherein said control means further calculates movement of the detection position based on the sensing signals of the plurality of frames, and identifies whether or not there is a touch based on the calculated movement of the detection position and said integrated value. A touch panel device as described. 4. The touch panel device according to any one of claims 1 to 3, wherein said control means distinguishes whether or not it is a long press touch. 2. The touch panel device according to claim 1, wherein said control means terminates calculation of said integrated value when touch detection is canceled from the touch panel. The touch panel device according to claim 1, wherein the touch panel is of a capacitive type or a resistive type. A display device comprising the touch panel device according to any one of claims 1 to 6 and a display for display.

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