CN111880674A - Touch detection method applied to touch display - Google Patents
Touch detection method applied to touch display Download PDFInfo
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- CN111880674A CN111880674A CN202010545568.7A CN202010545568A CN111880674A CN 111880674 A CN111880674 A CN 111880674A CN 202010545568 A CN202010545568 A CN 202010545568A CN 111880674 A CN111880674 A CN 111880674A
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- 238000001514 detection method Methods 0.000 title claims abstract description 47
- 230000003071 parasitic effect Effects 0.000 claims abstract description 37
- 238000000034 method Methods 0.000 claims abstract description 12
- 238000011156 evaluation Methods 0.000 claims description 10
- 230000001960 triggered effect Effects 0.000 description 3
- 229920001621 AMOLED Polymers 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
- G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
- G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
- G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
- G06F3/0416—Control or interface arrangements specially adapted for digitisers
- G06F3/0418—Control or interface arrangements specially adapted for digitisers for error correction or compensation, e.g. based on parallax, calibration or alignment
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
- G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
- G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
- G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
- G06F3/0412—Digitisers structurally integrated in a display
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
- G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
- G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
- G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
- G06F3/044—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means by capacitive means
Abstract
The invention provides a touch detection method applied to touch display, which is characterized in that whether a touch action exists on a touch display panel is judged according to a difference value between a current parasitic capacitance value and a reference value, wherein the reference value is a reference value used for judging whether a finger touches the touch display panel during normal scanning of TP; and recording the display brightness of the touch display panel as a reference brightness value when the reference value is updated, and updating the reference value of the touch display panel according to the difference value between the current brightness value and the reference brightness value of the touch display panel. According to the touch detection method applied to touch display, the reference value is updated according to the display brightness, the condition that parasitic capacitance value deviation caused by the change of the driving current value of the touch display panel is mistaken for a touch action is prevented, and the touch detection function can still work normally when a display part causes larger external load change in different display brightness change processes.
Description
Technical Field
The invention relates to the technical field of touch display, in particular to a touch detection method applied to touch display.
Background
With the continuous progress of the times, a touch display panel integrating a touch function and a display function is more and more valued and popular in the market, and the current process conditions also more and more adopt an AMOLED (active matrix organic light emitting diode display) mode to perform driving display. When the value of the driving current I is increased from I-I1 to I-I2 as shown in fig. 1, the parasitic capacitance value C of the OLED will increase from C1 to C2. It can be seen that when the driving current increases, the parasitic capacitance of the corresponding OLED light emitting diode increases relatively, thereby causing a difference in parasitic capacitance under different display luminance conditions, and from the above conclusion, it can be inferred that the corresponding parasitic capacitance is the smallest when displaying a black picture, and the corresponding parasitic capacitance is the largest when displaying a white picture, and under the display luminance conditions therebetween, the corresponding parasitic capacitance is in the range of the largest and smallest capacitance values corresponding to the black picture and the white picture.
The principle of self-capacitance TP (touch panel) detection is to determine finger touch by detecting capacitance changes at external touch detection points. When no finger touches, the difference between the parasitic capacitance value obtained by TP scanning and the base value (the reference value for judging whether the finger touches during TP normal scanning) is smaller than the detection threshold value of the finger touch, which indicates that no finger touches at this time, and when the finger touches, the external parasitic capacitance value is increased, and a corresponding parasitic capacitance value is generated, the parasitic capacitance value obtained by scanning at this time is larger than the parasitic capacitance value obtained by no finger touch, and when the difference value between the parasitic capacitance value and the base value at this time is larger than a certain set threshold value, the finger touches.
However, the capacitance at the external touch detection point may be changed due to the display brightness change, and therefore, the TP detection accuracy under different brightness conditions is likely to be affected, and the finger touch detection accuracy of the touch display panel with the touch function and the display function integrated is likely to be affected.
Fig. 2 is a schematic view of a touch display panel. Referring to fig. 2, in a touch display panel integrating touch function and display function, touch detection points and display pixels are also integrated, and their relationship is shown in fig. 3. Specifically, the touch display panel shown in fig. 3 includes N touch detection points T1-TN, i.e., N TP detection channels are provided, and one touch detection point includes M display pixels P1-PM, such that N × M display pixels are included in the area of the touch detection point.
Because the brightness displayed in the area of each touch detection point is different, different external parasitic capacitances can be generated, if the TP detection is performed on each detection channel during a black picture, and then the parasitic capacitance value detected at the moment is used as a base value, when the display is not in the black picture, the introduced parasitic capacitance can be changed differently due to different driving currents of the corresponding OLED light emitting diodes, so that even if no finger touches the panel currently, the parasitic capacitance value detected at the current TP still can be shifted, and if the difference between the current parasitic capacitance value and the base value exceeds the detection threshold value determined by the finger, the finger touch can be determined by mistake.
Therefore, in the conventional way of generating the BASE value by the CB automatic correction, the external load does not change much in the process of different display brightness changes, and therefore, the actual touch detection may not be disturbed, so that the BASE value generated under the black frame condition does not need to be updated again when the external condition changes. When the conventional method is applied to a touch display panel integrated with a touch function and a display function, when a display portion causes a large external load change in a process of changing different display brightness, the touch portion may easily misjudge that a finger is touching the panel.
Disclosure of Invention
Based on the technical problems in the background art, the invention provides a touch detection method applied to touch display.
The invention provides a touch detection method applied to touch display, which is characterized in that whether a touch action exists on a touch display panel is judged according to a difference value between a current parasitic capacitance value and a reference value, wherein the reference value is a reference value used for judging whether a finger touches the touch display panel during normal scanning of TP; and recording the display brightness of the touch display panel as a reference brightness value when the reference value is updated, and updating the reference value of the touch display panel according to the difference value between the current brightness value and the reference brightness value of the touch display panel.
Preferably, the updating the reference value of the touch display panel specifically includes the following steps:
s1, obtaining the parasitic capacitance value of each touch detection channel when the reference value is updated last time as the reference value, and obtaining the display brightness of the touch display panel when the reference value is updated as the reference brightness value;
s2, detecting the display brightness of the touch display panel, and calculating the absolute value of the difference between the detected current brightness value and the reference brightness value as an evaluation value;
and S3, comparing the evaluation value with a preset calibration threshold value, and when the evaluation value is larger than the calibration threshold value, correcting and updating the reference value under the current brightness value and updating the reference brightness value.
Preferably, in step S2, the display brightness of the touch display panel is periodically detected.
Preferably, the reference value is always a parasitic capacitance value in the null scan.
Preferably, the reference value is updated by CB calibration.
According to the touch detection method applied to touch display, the reference value is updated according to the display brightness, the condition that parasitic capacitance value deviation caused by the change of the driving current value of the touch display panel is mistaken for a touch action is prevented, and the touch detection function can still work normally when a display part causes larger external load change in different display brightness change processes.
Drawings
FIG. 1 is a schematic diagram illustrating parasitic capacitance value shift in a touch display panel;
FIG. 2 is a schematic view of a touch display panel;
fig. 3 is a flowchart illustrating a reference value updating method applied to a touch detection method for touch display according to the present invention.
Detailed Description
Referring to fig. 3, the touch detection method applied to touch display according to the present invention determines whether there is a touch action on the touch display panel according to a difference between a current parasitic capacitance value and a reference value, where the reference value is a reference value for determining whether there is a finger touch during TP normal scanning. In the method, the reference value is updated according to the display brightness of the touch display panel, and the specific method comprises the following steps: and recording the display brightness of the touch display panel as a reference brightness value when the reference value is updated, and updating the reference value of the touch display panel according to the difference value between the current brightness value and the reference brightness value of the touch display panel.
In the method, the reference value is updated according to the display brightness, so that the condition that parasitic capacitance value deviation caused by the change of the driving current value of the touch display panel is mistaken for a touch action is prevented, and the touch detection function can still work normally when the display part causes larger external load change in different display brightness change processes.
Specifically, in this embodiment, reference values of N touch detection channels are updated through a CB self-calibration process of the TP, and then reference values corresponding to each channel are obtained, so that N groups of reference values, namely base1 to base N, can be obtained in total. Therefore, each touch detection channel is subjected to touch judgment based on the independent reference value, and accurate detection of touch action is further guaranteed.
Meanwhile, in order to ensure the accuracy of the reference value, each time of CB calibration is performed without touch action, that is, the reference value is always the null scan parasitic capacitance value.
Specifically, in this embodiment, updating the reference value of the touch display panel specifically includes the following steps:
s1, obtaining the parasitic capacitance value of each touch detection channel when the reference value is updated last time as the reference value, and obtaining the display brightness of the touch display panel when the reference value is updated as the reference brightness value, which is denoted as LP 1. Specifically, the luminance value in the black screen is denoted by LB, and since the initial reference value update is performed in the black screen, the initial LP1 value is the LB value.
S2, detecting the display brightness of the touch display panel and recording the display brightness as LP2, and calculating the absolute value of the difference between the detected current brightness value LP2 and the reference brightness value LP1 as an evaluation value, namely the evaluation value is | LP2-LP1 |. Specifically, in this step, the display brightness of the touch display panel is periodically detected.
And S3, comparing the evaluation value with a preset calibration threshold value, and when the evaluation value is larger than the calibration threshold value, correcting and updating the reference value under the current brightness value and updating the reference brightness value.
Specifically, when TP is in the hardware monitor mode, if the reference value update condition is triggered, the parasitic capacitance value of each touch detection point obtained by current scanning is used as a new reference value of each channel to replace the previously obtained reference value, so as to complete the update of the reference value, otherwise, the reference value is not updated. At the same time, updating the display brightness information value corresponding to the current reference value is given to LP1, then the system continuously detects whether the absolute value | LP2-LP1| of the difference (LP 2-LP 1) meets the condition of reference value updating, if so, the updating of the reference value is continuously triggered, and if not, the current reference value is kept
Then, when performing touch determination, scanning the touch detection channel periodically, if a difference between a parasitic capacitance value of a certain currently scanned touch detection point and a reference value corresponding to the current channel is greater than a detection threshold value of finger touch, determining that there is finger touch at the touch detection point, otherwise, determining that there is no finger touch, and further elaborating the exit detection method provided by the present invention by combining a specific embodiment.
In this embodiment, it is assumed that the luminance information in the black screen is represented by LB, the luminance information of the corresponding display screen at the time of updating the current reference value is represented by LP1, and the luminance information in the current display screen is represented by LP2, the system is initially switched into the black screen, the luminance information corresponding to this time is LB, then CB automatic correction of TP is started, each SX channel is scanned, the CB value corresponding to each channel is configured to a reasonable range, that is, the CB value corresponding to each SX channel is configured such that the corresponding parasitic capacitance value is maintained in a specific region (for example, in a region of 250 to 300), after completion, the obtained parasitic capacitance values are used as the reference values of each SX channel, N groups of CB values and N reference values are obtained in total, and at the same time, the initial value of LP1 is the LB value. The display section then transmits the current display luminance information (LP2) to the TP section, and when the absolute value of the difference (LP 2-LP 1) is greater than a preset threshold value, it is determined that the reference value needs to be updated at this time. And if the TP is in the monitor mode, if the condition that the reference value needs to be updated is detected, the currently scanned blank scanning parasitic capacitance value is taken as a new reference value to replace the previous reference value, meanwhile, the display brightness information value corresponding to the current reference value is updated and is given to LP1, and whether the absolute value of (LP 2-LP 1) meets the condition of reference value updating is continuously detected, if so, the condition of reference value updating is continuously triggered, and if not, the current reference value is kept. And then judging whether the finger touches the screen currently or not by judging whether the difference value between the parasitic capacitance value scanned currently and the current reference value is larger than the threshold value of finger detection or not.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention are equivalent to or changed within the technical scope of the present invention.
Claims (5)
1. A touch detection method applied to touch display is characterized in that whether a touch action exists on a touch display panel is judged according to a difference value between a current parasitic capacitance value and a reference value, wherein the reference value is a reference value used for judging whether a finger touches the touch display panel during TP normal scanning; the method is characterized in that the display brightness of the touch display panel is recorded as a reference brightness value when the reference value is updated, and the reference value is updated according to the difference value between the current brightness value and the reference brightness value of the touch display panel.
2. The touch detection method applied to touch display of claim 1, wherein updating the reference value of the touch display panel specifically comprises:
s1, obtaining the parasitic capacitance value of each touch detection channel when the reference value is updated last time as the reference value, and obtaining the display brightness of the touch display panel when the reference value is updated as the reference brightness value;
s2, detecting the display brightness of the touch display panel, and calculating the absolute value of the difference between the detected current brightness value and the reference brightness value as an evaluation value;
and S3, comparing the evaluation value with a preset calibration threshold value, and when the evaluation value is larger than the calibration threshold value, correcting and updating the reference value under the current brightness value and updating the reference brightness value.
3. The touch detection method applied to touch display of claim 2, wherein in step S2, the display brightness of the touch display panel is periodically detected.
4. The touch detection method applied to touch display of claim 1, wherein the reference value is always a parasitic capacitance value during blank scanning.
5. The touch detection method applied to touch display of claim 4, wherein the reference value is updated by CB calibration.
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| CN202010545568.7A CN111880674A (en) | 2020-06-16 | 2020-06-16 | Touch detection method applied to touch display |
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| CN202010545568.7A CN111880674A (en) | 2020-06-16 | 2020-06-16 | Touch detection method applied to touch display |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113568495A (en) * | 2021-06-24 | 2021-10-29 | 合肥松豪电子科技有限公司 | Low-power-consumption design method for responding to human-computer interaction event in real time |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011175558A (en) * | 2010-02-25 | 2011-09-08 | Toshiba Tec Corp | Touch panel display apparatus and method for detecting the same |
| CN103105981A (en) * | 2011-11-14 | 2013-05-15 | 宸正光电（厦门）有限公司 | Touch screen device with correction function and correction method thereof |
| CN103971037A (en) * | 2013-02-06 | 2014-08-06 | 联发科技（新加坡）私人有限公司 | Control method and electronic device |
| JP2014186071A (en) * | 2013-03-22 | 2014-10-02 | Nec Saitama Ltd | Terminal device, information processing method and program |
| CN104571910A (en) * | 2013-10-25 | 2015-04-29 | 宏碁股份有限公司 | Electronic device and touch operation method thereof |
| CN109643200A (en) * | 2017-07-04 | 2019-04-16 | 深圳市汇顶科技股份有限公司 | The update method of a reference value of electronic equipment, touch detection circuit and touch screen |
| CN110568961A (en) * | 2019-09-05 | 2019-12-13 | 合肥松豪电子科技有限公司 | touch panel and touch detection method applied to touch panel |
-
2020
- 2020-06-16 CN CN202010545568.7A patent/CN111880674A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011175558A (en) * | 2010-02-25 | 2011-09-08 | Toshiba Tec Corp | Touch panel display apparatus and method for detecting the same |
| CN103105981A (en) * | 2011-11-14 | 2013-05-15 | 宸正光电（厦门）有限公司 | Touch screen device with correction function and correction method thereof |
| CN103971037A (en) * | 2013-02-06 | 2014-08-06 | 联发科技（新加坡）私人有限公司 | Control method and electronic device |
| US9552027B2 (en) * | 2013-02-06 | 2017-01-24 | Mediatek Singapore Pte. Ltd. | Control method and electronic device |
| JP2014186071A (en) * | 2013-03-22 | 2014-10-02 | Nec Saitama Ltd | Terminal device, information processing method and program |
| CN104571910A (en) * | 2013-10-25 | 2015-04-29 | 宏碁股份有限公司 | Electronic device and touch operation method thereof |
| EP2866127A1 (en) * | 2013-10-25 | 2015-04-29 | Acer Incorporated | Electronic apparatus and touch operating method thereof |
| CN109643200A (en) * | 2017-07-04 | 2019-04-16 | 深圳市汇顶科技股份有限公司 | The update method of a reference value of electronic equipment, touch detection circuit and touch screen |
| CN110568961A (en) * | 2019-09-05 | 2019-12-13 | 合肥松豪电子科技有限公司 | touch panel and touch detection method applied to touch panel |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113568495A (en) * | 2021-06-24 | 2021-10-29 | 合肥松豪电子科技有限公司 | Low-power-consumption design method for responding to human-computer interaction event in real time |
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Application publication date: 20201103 |