Touch-control display substrate and driving method therefor, driving circuit, and display device

Abstract

A touch-control display substrate and a driving method therefor, a driving circuit, and a display device, which relate to the technical field of display. The driving circuit is applied to a touch-control display substrate and a communication coil of the touch-control display substrate. The driving circuit comprises: a touch-control display module, which is connected to a touch-control display substrate; a communication module, which is connected to a communication coil and configured to provide a communication signal for the communication coil at a communication stage; and a processing module, which is connected to both the touch-control display module and the communication module and configured to provide a synchronization signal for the touch-control display module. The touch-control display module is configured to drive the touch-control display substrate to perform first touch-control detection and first image display according to the synchronization signal, and a first touch-control detection stage and the communication stage do not overlap.

Description

Touch display substrate, driving method thereof, driving circuit, and display device

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to Chinese patent application number 202310952673.6, filed with the China Patent Office on July 31, 2023, entitled “Touch display substrate and its driving method, driving circuit, and display device,” the entire contents of which are incorporated by reference into this disclosure. Technical Field

[0003] The present disclosure relates to the field of display technology, and in particular to a touch display substrate and a driving method, a driving circuit, and a display device thereof. Background Art

[0004] Near Field Communication (NFC) has the advantages of high security, fast response speed and low cost, and is widely used in mobile payment, electronic tickets, access control and other fields.

[0005] Overview

[0006] The present disclosure provides a driving circuit applied to a touch display substrate and a communication coil of the touch display substrate, the driving circuit comprising:

[0007] A touch display module connected to the touch display substrate;

[0008] a communication module connected to the communication coil and configured to provide a communication signal to the communication coil during a communication phase; and

[0009] a processing module, connected to the touch display module and the communication module respectively, and configured to provide a synchronization signal to the touch display module;

[0010] The touch display module is configured to drive the touch display substrate to perform a first touch detection and a first screen display according to the synchronization signal, and the first touch detection phase does not overlap with the communication phase.

[0011] In some embodiments, the communication phase includes a monitoring phase, the communication signal includes a monitoring signal, and the communication module is specifically configured to: provide the monitoring signal to the communication coil during the monitoring phase;

[0012] The synchronization signal includes a first synchronization signal, and the first synchronization signal is used to indicate the start of the monitoring phase;

[0013] The touch display module is specifically configured to: drive the touch display substrate to perform a first touch detection and a first screen display after receiving the first synchronization signal for a first duration, where the first duration is the duration of the monitoring phase.

[0014] In some embodiments, the first touch detection phase, the first image display phase, and the monitoring phase are three different phases within one frame period.

[0015] In some embodiments, the first touch detection phase is located between the first image display phase and the monitoring phase.

[0016] In some embodiments, the communication phase includes a read-write phase, the communication signal includes a read-write signal, and the communication module is specifically configured to: provide a read-write signal to the communication coil during the read-write phase;

[0017] The synchronization signal includes a second synchronization signal and a third synchronization signal, the second synchronization signal is used to indicate the start of the read / write phase, and the third synchronization signal is used to indicate the end of the read / write phase, and the processing module is specifically configured to: sequentially provide the second synchronization signal and the third synchronization signal to the touch display module;

[0018] The touch display module is configured to: after receiving the second synchronization signal and before receiving the third synchronization signal, drive the touch display substrate to display the first picture and stop the first touch detection.

[0019] In some embodiments, the touch display module is further configured to: drive the touch display substrate to display the first image and stop the first touch detection within N frame periods after receiving the third synchronization signal, where N is a positive integer.

[0020] In some embodiments, N is greater than or equal to 1 and less than or equal to 3.

[0021] In some embodiments, the processing module is further configured to:

[0022] Obtaining the power of the monitoring signal;

[0023] If the power is greater than or equal to a first threshold, the first synchronization signal is provided to the touch display module.

[0024] In some embodiments, the processing module is further configured to: provide an indication signal to the touch display module if the power is less than or equal to a second threshold, the second threshold being less than or equal to the first threshold;

[0025] The touch display module is further configured to: drive the touch display substrate to perform a second touch detection and a second screen display according to the indication signal, wherein the second touch detection phase and / or the second screen display phase overlaps with the monitoring phase.

[0026] In some embodiments, the processing module is connected to the touch display module via a two-wire serial bus or a flexible printed circuit board.

[0027] The present disclosure provides a touch display substrate, including a display area and a non-display area, wherein the display area includes a communication area and a non-communication area, and the touch display substrate includes:

[0028] A touch electrode, located in the display area, configured to transmit a touch signal during a touch detection phase;

[0029] an effective communication line, located in the communication area, configured to transmit a communication signal during a communication phase;

[0030] a virtual communication line, located in the non-communication area, configured to transmit the touch signal during the touch detection phase;

[0031] a plurality of scanning signal lines, located in the display area; and

[0032] A gate drive circuit is located in the non-display area, the gate drive circuit includes a plurality of shift registers cascaded with each other, the output end of the shift register is connected to the scan signal line, the shift register includes: a signal generating circuit, and a filtering circuit connected to the output end of the signal generating circuit, the signal generating circuit is configured to generate a scan signal, and the filtering circuit is configured to filter out high-frequency harmonics in the scan signal, the frequency of the high-frequency harmonics including the frequency of the subcarrier in the communication signal.

[0033] In some embodiments, the touch display substrate further includes:

[0034] The common signal line is located in the non-display area, connected to the virtual communication line, and configured to provide the touch signal to the virtual communication line during a touch detection phase.

[0035] In some embodiments, the touch display substrate further includes:

[0036] The connecting line is connected between the touch electrode and the virtual communication line, and is configured to transmit the signal on the touch electrode to the virtual communication line.

[0037] In some embodiments, the filtering circuit includes an RC filtering circuit.

[0038] The present disclosure provides a display device, comprising: a touch display substrate, a communication coil, and a driving circuit as described in any one of the above, wherein the driving circuit is respectively connected to the touch display substrate and the communication coil, and is configured to provide display signals and touch signals to the touch display substrate, and provide communication signals to the communication coil.

[0039] The present disclosure provides a display device, comprising:

[0040] The touch display substrate as described in any one of the items; and

[0041] A driving circuit is connected to the touch display substrate and is configured to provide a display signal, a communication signal, and a touch signal to the touch display substrate.

[0042] In some embodiments, the touch display substrate includes a plurality of sub-pixels arranged in an array, the touch display substrate supports a first frame frequency and a second frame frequency, the second frame frequency is greater than the first frame frequency, and a period corresponding to the first frame frequency is a first frame period. Within a first frame period, the driving method includes:

[0043] In the image refresh phase, each row of sub-pixels in the touch display substrate is charged row by row, and the charging time of a single row of sub-pixels is the charging time of a single row of sub-pixels at the second frame frequency;

[0044] During the image holding stage, the touch display substrate is driven to perform touch detection.

[0045] In some embodiments, the ratio of the duration of the picture holding phase to the first frame period is greater than or equal to 0.3 and less than or equal to 0.5.

[0046] In some embodiments, the communication coil of the touch display substrate is used to transmit communication signals, and the step of charging each row of sub-pixels in the touch display substrate row by row includes:

[0047] In response to the triggering of multiple valid pulses in the clock signal, each row of sub-pixels in the touch display substrate is charged row by row, and the clock signal is a periodic pulse signal, the frequency of the periodic pulse signal is the pulse frequency, and the even multiple of the pulse frequency is different from the frequency of the communication signal.

[0048] In some embodiments, the pulse frequency is greater than or equal to 10 KHz and less than or equal to 12 KHz; and / or

[0049] The frequency of the subcarrier in the communication signal is greater than or equal to 800 KHz.

[0050] The above description is only an overview of the technical solution of the present disclosure. In order to more clearly understand the technical means of the present disclosure, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present disclosure more obvious and easy to understand, the specific implementation methods of the present disclosure are listed below.

[0051] BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or related technologies, the following is a brief introduction to the drawings required for the description of the embodiments or related technologies. Obviously, the drawings described below are some embodiments of the present disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without inventive efforts. It should be noted that the scales in the drawings are for illustration only and do not represent the actual scale.

[0053] FIG1 exemplarily shows a structural diagram of a touch display substrate;

[0054] FIG2 exemplarily shows a structural diagram of another touch display substrate;

[0055] FIG3 exemplarily shows a schematic structural diagram of a gate drive circuit;

[0056] FIG4 exemplarily shows a schematic structural diagram of a shift register;

[0057] FIG5 exemplarily shows a timing diagram of signals loaded on the auxiliary communication line and the touch electrodes;

[0058] FIG6 exemplarily shows a schematic structural diagram of a driving circuit;

[0059] FIG7 exemplarily shows a schematic diagram of signal timings in the monitoring phase and the reading and writing phase;

[0060] FIG8 exemplarily shows a signal timing diagram of a driving process;

[0061] FIG9 exemplarily shows a schematic diagram of two touch detection results;

[0062] FIG10 exemplarily shows a curve showing the variation of filter bandwidth with sampling time;

[0063] FIG11 exemplarily shows another signal timing diagram of the driving process.

[0064] Detailed description

[0065] To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present disclosure without making any creative efforts shall fall within the scope of protection of the present disclosure.

[0066] In related technologies, NFC coils are constructed using metal leads on a printed circuit board (PCB) or flexible circuit board (FPC). This coil is then attached to the battery or housing of an electronic device. Repeated assembly and disassembly of the battery and housing can cause wear and misalignment of the NFC coil, affecting NFC signal transmission. This type of NFC coil occupies a large space inside the electronic device, increasing its thickness and making it unsuitable for the design requirements of small electronic products.

[0067] The design of integrating an NFC coil into a display substrate has the advantages of being integrated and lightweight. By forming an NFC coil structure in a specific film layer within the touch display substrate, the display substrate can provide both display functions and NFC communication functions, effectively improving the sensitivity and reliability of the NFC signal. Furthermore, the display substrate can also integrate a touch circuit to achieve the integration of display, touch, and communication functions. The inventors have found that products that integrate NFC coils into touch display substrates often experience touch ghosting or even touch failure issues, which greatly affects the user experience.

[0068] The present disclosure provides a touch display substrate, as shown in FIG1 or FIG2 , comprising a display area AA and a non-display area BZ. The display area AA comprises a communication area A1 and a non-communication area A2. The touch display substrate includes: touch electrodes 11 located in the display area AA and configured to transmit touch signals during a touch detection phase; effective communication lines 12 located in the communication area A1 and configured to transmit communication signals during a communication phase; and virtual communication lines 13 located in the non-communication area A2 and configured to transmit touch signals during a touch detection phase.

[0069] For example, as shown in FIG. 1 or FIG. 2 , in the communication area A1 , a plurality of effective communication lines 12 may be arranged to cross each other to form a grid structure, and the cross-arranged effective communication lines 12 may be connected to each other at the cross positions.

[0070] For example, as shown in Figures 1 or 2, in non-communication area A2, multiple virtual communication lines 13 can be arranged to intersect with each other to form a grid structure, and the intersecting effective communication lines 12 can be connected to each other at the intersections. By arranging virtual communication lines 13 in non-communication area A2 to form the same grid structure as communication area A1, the difference in transmittance between communication area A1 and non-communication area A2 can be reduced, and the display uniformity of display area AA can be improved.

[0071] In related art, as shown in Figure 5a, the virtual communication line 13 is connected to a DC regulated signal DC or ground, and the touch electrode 11 is connected to the touch signal St during the touch detection phase. This can easily cause touch problems in the non-communication area A2. The inventors have analyzed and found that this is due to the large coupling capacitance between the virtual communication line 13 and the touch electrode 11 in the non-communication area A2. When the voltage on the virtual communication line 13 and the touch electrode 11 is unequal, charge flow occurs. This charge flow causes the touch signal on the touch electrode 11 to change, resulting in abnormal touch function.

[0072] The touch display substrate provided by the present disclosure, as shown in Figure b in Figure 5, is configured to eliminate the voltage difference between the virtual communication line 13 and the touch electrode 11 by enabling the virtual communication line 13 to transmit the same touch signal St as the touch electrode 11 during the touch detection stage, thereby eliminating the charge flow caused by the coupling capacitor and ensuring the normal use of the touch function.

[0073] Exemplarily, the effective communication line 12 is equivalent to the communication coil of the touch display substrate, and can realize the NFC communication function.

[0074] Exemplarily, the touch electrode 11 may also be shared with the common electrode of the sub-pixels in the display area AA, and is also used to transmit a common voltage signal in a non-touch phase.

[0075] In order to enable the virtual communication line 13 to transmit touch signals during the touch detection stage, in a first embodiment, as shown in Figure 1, the touch display substrate also includes: a common signal line 14, located in the non-display area BZ, connected to the virtual communication line 13, and configured to provide touch signals to the virtual communication line 13 during the touch detection stage.

[0076] Exemplarily, as shown in FIG1 , the common signal line 14 can be connected to the touch display module 15 through a flexible circuit board to receive the VCOM OPT signal generated by the touch display module 15 . During the touch detection phase, the VCOM OPT signal and the touch signal are synchronous signals with the same amplitude and frequency, thereby enabling the touch signal to be loaded onto the virtual communication line 13 during the touch detection phase.

[0077] Exemplarily, the touch display module 15 is a touch and display driver integration (TDDI) chip.

[0078] Exemplarily, the common signal line 14 is further used to provide a common voltage signal to the virtual communication line 13 in a non-touch stage.

[0079] In order to enable the virtual communication line 13 to transmit touch signals during the touch detection stage, in a second embodiment, as shown in Figure 2, the touch display substrate also includes: a connecting line 21, connected between the touch electrode 11 and the virtual communication line 13, and configured to transmit the signal on the touch electrode 11 to the virtual communication line 13.

[0080] Exemplarily, as shown in FIG. 2 , the virtual communication line 13 may be connected to the touch electrode 11 via a connecting line 21 .

[0081] Compared with the first embodiment, in the second embodiment, the problem of uneven display is easily caused due to the heavy load of the virtual communication line 13. The first embodiment can avoid the problem of uneven display, and because the common signal line 14 is directly connected to the driver chip 15, it will not affect the touch or display functions.

[0082] If the touch display substrate is considered a field, the signals it covers include high-voltage display signals, such as scanning signals. Because the touch display substrate is located between the transmitting and receiving antennas, the higher-order harmonics in these display signals can be spatially coupled to the communication signal's subcarrier (e.g., 847 kHz), thereby affecting NFC communication functionality. Furthermore, since the scanning signal is a square wave, the most typical distorted wave, composed of various harmonics, and the voltage difference of the scanning signal is large, its harmonics have large amplitudes. Therefore, it is necessary to filter harmonics above 800 kHz in the display signal.

[0083] To filter harmonics above 800 kHz in the scan signal, in some embodiments, as shown in Figures 1 or 2 , the touch display substrate further includes: multiple scan signal lines 16 located in the display area AA; and a gate drive circuit 17 located in the non-display area BZ. As shown in Figure 3 , the gate drive circuit 17 includes multiple shift registers 31 connected in cascade, with the output terminals Gout of the shift registers 31 connected to the scan signal lines 16. In Figure 3 , gate-1 through gate-1280 represent the scan signal lines 16.

[0084] As shown in Figure 4, the shift register 31 includes: a signal generating circuit 41, and a filtering circuit 42 connected to the output terminal Gout0 of the signal generating circuit 41, the signal generating circuit 41 is configured to generate a scanning signal, and the filtering circuit 42 is configured to filter out high-frequency harmonics in the scanning signal, and the frequency of the high-frequency harmonics includes the frequency of the subcarrier in the communication signal.

[0085] In this embodiment, by setting a filter circuit 42 in the shift register 31, the output terminal Gout0 of the signal generating circuit 41 of the scanning signal is connected to the filter circuit 42, which can filter out the harmonic components in the scanning signal that are close to the subcarrier frequency in the communication signal, reduce interference with the communication signal, and facilitate the normal use of the NFC communication function.

[0086] Exemplarily, the frequency of the subcarrier in the communication signal may be greater than or equal to 800 KHz, such as 847 KHz.

[0087] Exemplarily, the filter circuit 42 is a low-pass filter circuit 42 , and the cut-off frequency can be set to 800 kHz, for example.

[0088] In some embodiments, as shown in FIG. 4 , the filter circuit 42 includes an RC filter circuit 42 .

[0089] Exemplarily, as shown in FIG4 , the RC filter circuit 42 includes: a resistor R located between the output terminal Gout0 of the signal generating circuit 41 and the output terminal Gout of the shift register 31 , and a capacitor C connected between the output terminal Gout of the shift register 31 and the ground potential GND.

[0090] According to the first-order RC low-pass filter cutoff frequency formula: f0 = 1 / 2πRC, if the cutoff frequency is set to 800kHz, the resistor R can be 800Ω and the capacitor C can be 20pF. In specific implementations, the capacitance of capacitor C can be designed to be greater than or equal to 15pF and less than or equal to 25pF based on factors such as product resolution, frame rate, and the location of the NFC coil.

[0091] In practice, there are two ways to perform NFC card swiping: the first is to place the NFC coil on the back of the display surface of the display substrate, and place ferrite between the NFC coil and the display substrate for isolation, which can achieve better isolation effect; the second is to place the NFC coil on the outer edge of the display device housing, and then place ferrite on the side of the NFC coil away from the display surface of the display substrate. However, since the NFC coil is close to the display substrate and no absorbing material such as ferrite is placed between the NFC coil and the display substrate, the subcarrier signal in the communication signal is easily affected by the display signal, which hinders the development of card swiping applications on the front of the screen. The subcarrier signal frequency range is, for example, 800kHz to 900kHz.

[0092] The touch display substrate provided in this embodiment can filter the scanning signal at high frequency from the source, effectively reducing the interference of the scanning signal on the subcarrier signal in the communication signal. Therefore, it is conducive to the promotion of front-side card swiping applications.

[0093] It should be noted that the touch display substrate provided by the present disclosure is suitable for application scenarios of back-side card swiping or front-side card swiping.

[0094] The present disclosure provides a driving circuit, which is applied to a touch display substrate PNL and a communication coil AW of the touch display substrate PNL. As shown in Figure 6, the driving circuit includes: a touch display module 61, which is connected to the touch display substrate PNL; a communication module 62, which is connected to the communication coil AW and is configured to provide a communication signal to the communication coil AW during the communication stage; and a processing module 63, which is respectively connected to the touch display module 61 and the communication module 62 and is configured to provide a synchronization signal to the touch display module 61.

[0095] The touch display module 61 is configured to drive the touch display substrate PNL to perform a first touch detection and a first image display according to the synchronization signal, and the first touch detection phase TC1 does not overlap with the communication phase.

[0096] Exemplarily, the synchronization signal is used to indicate the start and / or end of a communication phase.

[0097] For example, as shown in FIG7 , a frame period T can be divided into a first picture refresh phase FR1 and a first picture holding phase RT1. For example, the step in which the touch display module 61 drives the touch display substrate PNL to display the first picture can be performed in the first picture refresh phase FR1, and the step in which the touch display module 61 drives the touch display substrate PNL to perform the first touch detection can be performed in the first picture holding phase RT1.

[0098] For example, the communication phase may include a listening phase LS and a read / write phase RW. In the listening phase LS, the communication coil AW (i.e., the NFC coil) emits a carrier wave at a fixed time to detect whether there is a card nearby. After a card is detected, the communication phase RW is entered, during which the card's internal information is read.

[0099] During the monitoring phase LS, the communication coil AW sends a communication signal at a fixed time interval, and the communication signal has a voltage jump. The inventors have found that this voltage jump may cause the problem of touch ghost points, and it may occur at any time point in a frame period T.

[0100] During the read / write phase RW, the communication signal constantly experiences voltage jumps, which can also cause touch ghosting, and can occur at any point within a frame period T. The duration of the read / write phase RW is positively correlated with the amount of card information; generally, the duration of the read / write phase RW is greater than the duration of touch detection within a frame period T. The inventors have also discovered that touch ghosting can also occur after switching from the read / write phase RW to the listening phase LS.

[0101] The driver circuit provided herein uses a synchronization signal to ensure that the first touch detection phase TC1 and the communication phase do not overlap. Specifically, the first touch detection phase TC1 and the communication phase are performed in separate time periods. During the communication phase, the touch display module 61 disables the first touch detection function, while during the non-communication phase, the touch display module 61 activates the first touch detection function. By performing communication and first touch detection at different times, noise interference from communication on touch detection can be more thoroughly eliminated, addressing issues such as touch ghosting and touch malfunction, and ensuring the normal operation of the touch detection function. The communication phase includes a listening phase LS and a read / write phase RW.

[0102] Exemplarily, the touch display substrate PNL may be the touch display substrate PNL provided in any embodiment.

[0103] For example, the communication coil AW may be integrated into the touch display substrate PNL, such as including an effective communication line integrated into the touch display substrate PNL, or may be provided independently of the touch display substrate PNL, which is not limited in the present disclosure.

[0104] Exemplarily, the processing module 63 may be a microcontroller unit (MCU) on a mainboard.

[0105] Exemplarily, the touch display module 61 is a touch and display driver integration (TDDI) chip.

[0106] In some embodiments, the communication phase includes a listening phase LS, the communication signal includes a listening signal, and the communication module 62 is specifically configured to provide the listening signal to the communication coil AW during the listening phase LS.

[0107] In this embodiment, the synchronization signal includes a first synchronization signal S1, which is used to indicate the start of the listening phase LS. Accordingly, as shown in FIG7 a, the touch display module 61 is specifically configured to drive the touch display substrate PNL to perform a first touch detection and a first screen display after receiving the first synchronization signal S1 for a first duration t1, where the first duration t1 is the duration of the listening phase LS.

[0108] For example, as shown in Figure a in Figure 7, the first picture retention stage RT1 can be divided into the first touch detection stage TC1 and the listening stage LS. For example, the step of the touch display module 61 driving the touch display substrate PNL to perform the first touch detection can be performed in the first touch detection stage TC1, and the step of the communication module 62 executing the listening stage LS can be performed in the listening stage LS.

[0109] For example, in the first picture holding phase RT1, the first touch detection phase TC1 may be performed before the listening phase LS, as shown in Figure 7a. Of course, in the first picture holding phase RT1, the first touch detection phase TC1 may also be performed after the listening phase LS, which is not limited in this disclosure.

[0110] For example, as shown in FIG. 7 a , the touch display integrated core may first drive the touch display substrate PNL to display a first picture after receiving the first synchronization signal S1 for a first duration t1 , and then drive the touch display substrate PNL to perform a first touch detection.

[0111] As shown in Figure 7a, when the touch display module 61 receives the first synchronization signal S1, the communication module 62 begins executing the steps of the monitoring phase LS. After a first duration t1, the monitoring phase LS ends. The touch display module 61 then drives the touch display substrate PNL to sequentially perform the first image display and the first touch detection. In this way, the first synchronization signal S1 allows the monitoring phase LS and the first touch detection to be performed in a time-sharing manner, eliminating touch ghosting and touch failure issues that may occur during the monitoring phase LS.

[0112] In some embodiments, as shown in FIG. 7 a , the first touch detection phase TC1 , the first image display phase FR1 , and the monitoring phase LS are three different phases within one frame period.

[0113] In order to further reduce the impact of communication on touch detection, the first touch detection phase TC1 is located between the first frame display phase FR1 and the listening phase LS.

[0114] For example, as shown in Figure a in Figure 7, within a frame period T, the first picture display stage FR1, the first touch detection stage TC1 and the monitoring stage LS are performed in sequence without overlapping with each other. This prevents the picture display, touch and communication from interfering with each other, eliminating the problems of touch ghost points and touch failure.

[0115] In some embodiments, the communication phase includes a read-write phase RW, the communication signal includes a read-write signal, and the communication module 62 is specifically configured to provide a read-write signal to the communication coil AW during the read-write phase RW.

[0116] In this embodiment, the synchronization signal includes a second synchronization signal and a third synchronization signal. The second synchronization signal is used to indicate the start of the read and write phase RW, and the third synchronization signal is used to indicate the end of the read and write phase RW. The processing module 63 is specifically configured to: provide the second synchronization signal S2 and the third synchronization signal S3 to the touch display module 61 in sequence.

[0117] Accordingly, as shown in FIG. 7 b , the touch display module 61 is configured to drive the touch display substrate PNL to display the first screen and stop the first touch detection after receiving the second synchronization signal S2 and before receiving the third synchronization signal S3 .

[0118] Exemplarily, as shown in FIG. 7 b , the read / write phase RW may occur in the first frame refresh phase FR1 and / or the first frame hold phase RT1 .

[0119] As shown in Figure 7b, the touch display module 61 first receives the second synchronization signal S2, and the read / write phase RW begins. Subsequently, the touch display module 61 receives the third synchronization signal S3, and the read / write phase RW ends. During the first frame refresh phase FR1 of the read / write phase RW, the touch display module 61 drives the touch display substrate PNL to display the first frame. During the first frame hold phase RT1 of the read / write phase RW, the first touch detection function is suspended. Thus, during the read / write phase RW, touch detection is suspended, and the display function remains normal. By using the second synchronization signal S2 and the third synchronization signal S3, the read / write phase RW and touch detection can be time-shared, eliminating touch ghosting and touch failure issues that may occur during the read / write phase RW.

[0120] In some embodiments, the touch display module 61 is further configured to: drive the touch display substrate PNL to display the first image and stop the first touch detection within N frame periods T after receiving the third synchronization signal S3, where N is a positive integer.

[0121] As shown in Figure 7b, the touch display module 61 receives the third synchronization signal S3, and the read / write phase RW ends. Within N frame periods T after the read / write phase RW, the touch display module 61 drives the touch display substrate PNL to display the first image. Furthermore, within N frame periods T after the read / write phase RW, the touch display module 61 stops the first touch detection function during the first image retention phase RT1. In other words, the touch detection function is stopped N frame periods T after the read / write phase RW, and the display function remains normal. This prevents touch ghosting and touch failure caused by mode switching.

[0122] In some embodiments, N is greater than or equal to 1 and less than or equal to 3.

[0123] Exemplarily, as shown in FIG. 7 b , after receiving the third synchronization signal S3 , the touch display module 61 suspends the touch detection function of the current frame; and then drives the touch display substrate PNL to perform the first touch detection and the first screen display according to the received synchronization signal.

[0124] In some embodiments, the processing module 63 is further configured to: obtain the power of the monitoring signal; and provide a first synchronization signal S1 to the touch display module 61 if the power is greater than or equal to a first threshold.

[0125] When the power of the monitoring signal is large, conventional filtering algorithms cannot completely eliminate the noise interference caused by the communication signal to the touch signal. In this case, it is necessary to use the first synchronization signal S1 to realize the time-sharing of the monitoring phase LS and the touch detection phase, so as to ensure the normal use of the touch function.

[0126] In some embodiments, the processing module 63 is further configured to provide an indication signal to the touch display module 61 if the power is less than or equal to a second threshold, and the second threshold is less than or equal to the first threshold. Accordingly, the touch display module 61 is further configured to drive the touch display substrate PNL to perform a second touch detection phase and a second screen display phase based on the indication signal, wherein the second touch detection phase and / or the second screen display phase overlap with the monitoring phase LS.

[0127] For example, as shown in FIG. 7 c, a frame period T can be divided into a second image refresh phase FR2 and a second image retention phase RT2. For example, during the second image refresh phase FR2, the touch display module 61 can drive the touch display substrate PNL to display the second image, and during the second image retention phase RT2, the touch display substrate PNL can be driven to perform a second touch detection. As shown in FIG. 7 c, both the second image refresh phase FR2 and the second image retention phase RT2 overlap with the monitoring phase LS.

[0128] When the monitoring signal power is low, conventional filtering algorithms can eliminate noise interference from the communication signal on the touch signal. This ensures normal use of the touch function even when the monitoring phase LS and the touch detection phase are performed simultaneously. Furthermore, real-time, uninterrupted touch control is achieved, improving touch detection performance. Therefore, when the monitoring signal power is low, this embodiment supports the simultaneous operation of the touch function and the monitoring function.

[0129] In some embodiments, the processing module 63 is connected to the touch display module 61 via a two-wire serial bus.

[0130] In this embodiment, the processing module 63 can send a synchronization signal to the touch display module 61 via a two-wire serial bus. The synchronization signal, for example, includes a first synchronization signal S1 such as 00, which is used to indicate the start of the listening phase LS, a second synchronization signal S2 such as 01, which is used to indicate the start of the read / write phase RW, and a third synchronization signal S3 such as 10, which is used to indicate the end of the read / write phase RW.

[0131] In this embodiment, the processing module 63 can also send the same synchronization signal to the communication module 62 through the GPIO interface on the board. For example, the communication module 62 can also start the listening phase LS according to the first synchronization signal S1, start the reading and writing phase RW according to the second synchronization signal S2, and end the reading and writing phase RW according to the third synchronization signal S3.

[0132] This embodiment does not require any special changes to the hardware of the processing module 63, and the range of hardware options is wider.

[0133] In some embodiments, the processing module 63 is connected to the touch display module 61 via a flexible circuit board.

[0134] For example, the processing module 63 can use a general-purpose input / output (GPIO) port on the hardware to send the analog synchronization signal to the touch display module 61 via a flexible circuit board. The touch display module 61 then determines the type of synchronization signal based on the received analog synchronization signal. The types of synchronization signals may include: a first synchronization signal S1 indicating the start of a listening phase LS, a second synchronization signal S2 indicating the start of a read / write phase RW, and a third synchronization signal S3 indicating the end of the read / write phase RW.

[0135] The present disclosure provides a display device, as shown in Figure 6, including: a touch display substrate PNL, a communication coil AW, and a driving circuit DR provided in any embodiment, the driving circuit DR is respectively connected to the touch display substrate PNL and the communication coil AW, and is configured to provide display signals and touch signals to the touch display substrate PNL, and provide communication signals to the communication coil AW.

[0136] In the present disclosure, the communication coil AW may be integrated into the touch display substrate PNL, or may be provided independently of the touch display substrate PNL.

[0137] Those skilled in the art will appreciate that the display device has the advantages of the driving circuit provided in the previous embodiments.

[0138] The present disclosure provides a display device, as shown in Figure 6, including: a touch display substrate PNL as provided in any embodiment, and a driving circuit DR, the driving circuit DR is connected to the touch display substrate PNL and is configured to provide display signals, touch signals and communication signals to the touch display substrate PNL.

[0139] In the present disclosure, the touch display substrate PNL includes an effective communication line 12 , which is equivalent to integrating a communication coil AW.

[0140] Those skilled in the art will appreciate that the display device has the advantages of the touch display substrate PNL provided in the previous embodiments.

[0141] Exemplarily, the display device provided in the present disclosure is a product with an image display function. For example, the display device can be: a display, a television, a billboard, a digital photo frame, a laser printer with a display function, a telephone, a mobile phone, a personal digital assistant (PDA), a sales terminal, a digital camera, a camcorder, a viewfinder, a navigator, a vehicle, a large-area wall, a home appliance, an information query device (such as business query equipment of e-government, banks, hospitals, power departments, etc.), and a monitor. The display device can also be a microdisplay or a product containing a microdisplay. The product containing a microdisplay can be any one of a smart watch, a smart bracelet, a helmet display, a stereo display mirror, an AR device (such as AR glasses), and a VR device (such as VR glasses).

[0142] The present disclosure provides a driving method for a touch display substrate PNL. The touch display substrate PNL includes a plurality of sub-pixels arranged in an array. The touch display substrate PNL supports a first frame frequency and a second frame frequency. The second frame frequency is greater than the first frame frequency. A period corresponding to the first frame frequency is a first frame period T1. Within a first frame period T1, the driving method includes:

[0143] Step S11 : in the frame refresh phase FR, charging the sub-pixels in each row in the touch display substrate PNL row by row, and the charging time of the sub-pixels in a single row is the charging time of the sub-pixels in a single row at the second frame frequency.

[0144] Step S12: During the image retention phase RT, the touch display substrate PNL is driven to perform touch detection.

[0145] For example, the charging time of a single row of sub-pixels multiplied by the number of rows of sub-pixels is roughly the duration of the image refresh phase FR. As shown in FIG8 , the total duration of the image refresh phase FR and the image hold phase RT is one frame period T.

[0146] For example, the first frame frequency may be 60 Hz, and the second frame frequency may be 90 Hz or 120 Hz; or the first frame frequency may be 90 Hz, and the second frame frequency may be 120 Hz.

[0147] The driving method provided in the present disclosure can be applied to the touch display substrate PNL provided in any embodiment.

[0148] In the related art, when the frame frequency is the first frame frequency, the charging time of a single row of sub-pixels is the charging time of a single row of sub-pixels at the first frame frequency. The charging time of a single row of sub-pixels is longer, so the duration of the screen refresh phase FR is longer, the duration of the screen hold phase RT for touch detection is shorter, and the number of touch sampling cycles is smaller. Taking the 5.65-inch touch display substrate PNL as an example, the resolution is 720RGB×1440, as shown in Figure a in Figure 8, when the first frame frequency is 60Hz, the charging time of a single row of sub-pixels is 10 microseconds, the duration of the screen refresh phase FR is 14.67ms, the duration of the screen hold phase RT is 2ms, and the number of touch sampling cycles is 12. In this case, there is a problem of touch ghost points. Referring to Figure a in Figure 9, a schematic diagram of the touch detection results in the related art is shown. There is a risk of reporting points in the communication area A1 (the gray area in the figure).

[0149] The driving method provided by the present disclosure is that, when the frame frequency is the first frame frequency, the charging time of a single row of sub-pixels is the same as the charging time of a single row of sub-pixels at the second frame frequency, which is shorter than the charging time of a single row of sub-pixels at the first frame frequency. This is equivalent to shortening the charging time of a single row of sub-pixels, thereby shortening the duration of the screen refresh phase FR and extending the duration of the screen retention phase RT, thereby increasing the number of touch sampling cycles. Taking the 5.65-inch touch display substrate PNL as an example, with a resolution of 720RGB×1440, as shown in Figure 8b, when the first frame frequency is 60Hz, the charging time of a single row of pixels is reduced from the original 10 microseconds to about 6.5 microseconds (when the second frame frequency is 90Hz, the charging time of a single row of sub-pixels is the same), shortening the charging time of a single row of pixels by one third, and extending the duration of the image retention phase RT from the original 2ms to about 7.5ms. As a result, the number of touch sampling cycles is increased from the original 12 to 60, which can collect more noise data, improve noise optimization effects and noise resistance, and improve the signal-to-noise ratio of the touch signal. Referring to Figure 9b, a schematic diagram of the touch detection results of the driving method provided by the present disclosure is shown. In the entire display area AA, including the communication area A1 and the non-communication area A2, there is no risk of reporting points.

[0150] In specific implementation, the bandwidth of the digital filter can be reduced to avoid the operating frequency of NFC. According to the following multi-point mean filter formula:

[0151] Where f is the sampling frequency, M is the number of sampling points, and H is the bandwidth. It can be seen that at the same sampling frequency, the greater the number of sampling points, the smaller the filter bandwidth will be, as shown in Figure 10. This allows more noise signals to be filtered out, resulting in a higher signal-to-noise ratio and better noise immunity.

[0152] The driving method provided in the present disclosure can improve the noise filtering effect and increase the signal-to-noise ratio by extending the touch detection time and increasing the number of sampling points.

[0153] In some embodiments, the ratio of the duration of the picture holding period RT to the first frame period T1 is greater than or equal to 0.3 and less than or equal to 0.5. For example, the ratio of the duration of the picture holding period RT to the first frame period T1 is 0.45.

[0154] In some embodiments, the communication coil AW of the touch display substrate PNL is used to transmit communication signals. Step S11 may specifically include:

[0155] Step S21: In response to the triggering of multiple valid pulses PLS in the clock signal CLK, each row of sub-pixels in the touch display substrate PNL is charged row by row. As shown in Figure 11, the clock signal CLK is a periodic pulse signal with a frequency equal to the pulse frequency. Even multiples of the pulse frequency are different from the frequency of the communication signal.

[0156] Exemplarily, the pulse frequency may be a scanning frequency, for example, the product of a frame frequency of the touch display substrate PNL and the number of sub-pixel rows.

[0157] Exemplarily, the clock signal CLK is a square wave signal with an amplitude of 30V.

[0158] In specific implementation, the pulse frequency can be adjusted to prevent its even-numbered multiple frequency from falling within the frequency range of the communication signal, for example, to prevent its even-numbered multiple frequency from being 847 kHz.

[0159] When the pulse frequency is changed, the duration of the picture holding period RT and the duty cycle of the clock signal CLK can be adjusted accordingly.

[0160] In some embodiments, the pulse frequency is greater than or equal to 10 KHz and less than or equal to 12 KHz.

[0161] For example, taking a full HD touch display substrate PNL with a frame frequency of 60 Hz as an example, the pulse frequency is 10 kHz and is less than or equal to 12 kHz.

[0162] In some embodiments, the frequency of the subcarrier in the communication signal is greater than or equal to 800 KHz.

[0163] Among them, the center frequency of the NFC coil operating frequency band is 13.56Mhz.

[0164] For example, the communication coil AW may be integrated into the touch display substrate PNL, or may be provided independently of the touch display substrate PNL, which is not limited in the present disclosure.

[0165] In the present disclosure, “a plurality of” means two or more, and “at least one” means one or more, unless otherwise clearly defined.

[0166] In the present disclosure, the orientation or positional relationship indicated by the terms "upper" and "lower" is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present disclosure and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it should not be understood as a limitation on the present disclosure.

[0167] As used herein, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, product, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the process, method, commodity, or apparatus that includes the element.

[0168] References herein to "one embodiment," "some embodiments," "exemplary embodiments," "one or more embodiments," "an example," "an example," "some examples," and the like are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of the present disclosure. Schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be included in any one or more embodiments or examples in any suitable manner.

[0169] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any actual relationship or order between these entities or operations.

[0170] When describing some embodiments, the expressions "coupled" and "connected" may be used. For example, when describing some embodiments, the term "connected" may be used to indicate that two or more components are in direct physical or electrical contact with each other. For another example, when describing some embodiments, the term "coupled" may be used to indicate that two or more components are in direct physical or electrical contact. However, the term "coupled" or "communicatively coupled" may also mean that two or more components are not in direct contact with each other, but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the contents of this document.

[0171] “At least one of A, B and C” has the same meaning as “at least one of A, B or C” and both include the following combinations of A, B and C: A only, B only, C only, the combination of A and B, the combination of A and C, the combination of B and C, and the combination of A, B and C.

[0172] “A and / or B” includes the following three combinations: A only, B only, and a combination of A and B.

[0173] As used herein, the term "if" is optionally interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined that" or "if [stated condition or event] is detected" are optionally interpreted to mean "upon determining" or "in response to determining" or "upon detecting [stated condition or event]" or "in response to detecting [stated condition or event]," depending on the context.

[0174] The use of "for" or "configured to" herein is intended to be open and inclusive language that does not exclude devices adapted or configured to perform additional tasks or steps.

[0175] The use of "based on" or "according to" in this document is intended to be open and inclusive. A process, step, calculation, or other action based on one or more stated conditions or values ​​may, in practice, be based on other conditions or values ​​beyond the stated values. A process, step, calculation, or other action based on one or more stated conditions or values ​​may, in practice, be based on other conditions or values ​​beyond the stated values.

[0176] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of deviation from the particular value as determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0177] As used herein, "parallel", "perpendicular", "equal", and "flush" include the situations described and situations similar to the situations described, the range of which is within an acceptable deviation range, wherein the acceptable deviation range is as determined by a person of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the specific quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein the acceptable deviation range of approximate parallelism can be, for example, a deviation within 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range of approximate perpendicularity can also be, for example, a deviation within 5°. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of approximate equality can be, for example, the difference between the two being equal is less than or equal to 5% of either one. "Flush" includes absolute equality and approximate flushness, wherein the acceptable deviation range of approximate flushness can be, for example, the distance between the two being flush is less than or equal to 5% of either one's size.

[0178] It will be understood that when a layer or element is referred to as being on another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may be present therebetween.

[0179] Exemplary embodiments are described herein with reference to cross-sectional and / or plan views that are idealized exemplary drawings. In the drawings, the thicknesses of layers and regions are exaggerated for clarity. Therefore, variations in shape relative to the drawings due to, for example, manufacturing techniques and / or tolerances are contemplated. Therefore, the exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but rather include deviations in shape due to, for example, manufacturing. For example, an etched region shown as a rectangle will typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to illustrate the actual shape of regions of the device and are not intended to limit the scope of the exemplary embodiments. Unless otherwise specified, the thickness of a film layer refers to the dimension of the film layer in the direction normal to it.

[0180] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present disclosure.

Claims

1. A driving circuit applied to a touch display substrate and a communication coil of the touch display substrate, the driving circuit comprising: A touch display module connected to the touch display substrate; a communication module, connected to the communication coil, and configured to provide a communication signal to the communication coil during a communication phase; as well as a processing module, connected to the touch display module and the communication module respectively, and configured to provide a synchronization signal to the touch display module; The touch display module is configured to: drive the touch display substrate to perform a first touch detection and a first screen display according to the synchronization signal, and the first touch detection phase does not overlap with the communication phase.

2. The driving circuit according to claim 1, wherein: The communication phase includes a monitoring phase, the communication signal includes a monitoring signal, and the communication module is specifically configured to: provide a monitoring signal to the communication coil during the monitoring phase; The synchronization signal includes a first synchronization signal, and the first synchronization signal is used to indicate the start of the monitoring phase; The touch display module is specifically configured to: after receiving the first synchronization signal for a first duration, drive the touch display substrate to perform a first touch detection and a first screen display, wherein the first duration is the duration of the monitoring phase.

3. The driving circuit according to claim 2, wherein: The first touch detection phase, the first picture display phase and the monitoring phase are three different phases within one frame period.

4. The driving circuit according to claim 3, wherein: The first touch detection phase is located between the first picture display phase and the monitoring phase.

5. The driving circuit according to claim 1, wherein: The communication phase includes a read-write phase, the communication signal includes a read-write signal, and the communication module is specifically configured to: provide a read-write signal to the communication coil during the read-write phase; The synchronization signal includes a second synchronization signal and a third synchronization signal, wherein the second synchronization signal is used to indicate the start of the read / write phase, and the third synchronization signal is used to indicate the end of the read / write phase. The processing module is specifically configured to: sequentially provide the second synchronization signal and the third synchronization signal to the touch display module; The touch display module is configured to: after receiving the second synchronization signal and before receiving the third synchronization signal, drive the touch display substrate to display the first picture and stop the first touch detection.

6. The driving circuit according to claim 5, wherein: The touch display module is further configured to: drive the touch display substrate to display the first picture and stop the first touch detection within N frame periods after receiving the third synchronization signal, where N is a positive integer.

7. The driving circuit according to claim 6, wherein: The N is greater than or equal to 1 and less than or equal to 3.

8. The driving circuit according to claim 2, wherein: The processing module is further configured to: Acquiring the power of the monitoring signal; If the power is greater than or equal to a first threshold, the first synchronization signal is provided to the touch display module.

9. The driving circuit according to claim 7, wherein: The processing module is further configured to: provide an indication signal to the touch display module if the power is less than or equal to a second threshold, the second threshold being less than or equal to the first threshold; The touch display module is further configured to: drive the touch display substrate to perform a second touch detection and a second screen display according to the indication signal, wherein the second touch detection phase and / or the second screen display phase overlaps with the monitoring phase.

10. The driving circuit according to any one of claims 1 to 9, wherein: The processing module is connected to the touch display module via a two-wire serial bus or a flexible printed circuit board.

11. A touch display substrate, comprising a display area and a non-display area, wherein the display area comprises a communication area and a non-communication area, and the touch display substrate comprises: A touch electrode, located in the display area, configured to transmit a touch signal during a touch detection phase; An effective communication line, located in the communication area, configured to transmit a communication signal during a communication phase; a virtual communication line, located in the non-communication area, configured to transmit the touch signal during the touch detection phase; A plurality of scanning signal lines are located in the display area; as well as A gate drive circuit is located in the non-display area, the gate drive circuit includes a plurality of shift registers cascaded to each other, the output end of the shift register is connected to the scan signal line, the shift register includes: a signal generating circuit, and a filter circuit connected to the output end of the signal generating circuit, the signal generating circuit is configured to generate a scan signal, and the filter circuit is configured to filter out high-frequency harmonics in the scan signal, the frequency of the high-frequency harmonics includes the frequency of the subcarrier in the communication signal.

12. The touch display substrate according to claim 11, wherein: The touch display substrate further includes: The common signal line is located in the non-display area, connected to the virtual communication line, and configured to provide the touch signal to the virtual communication line during a touch detection phase.

13. The touch display substrate according to claim 11, wherein: The touch display substrate further includes: A connecting line is connected between the touch electrode and the virtual communication line, and is configured to transmit the signal on the touch electrode to the virtual communication line.

14. The touch display substrate according to any one of claims 11 to 13, wherein: The filter circuit includes an RC filter circuit.

15. A display device, comprising: A touch display substrate, a communication coil, and a driving circuit as described in any one of claims 1 to 10, wherein the driving circuit is respectively connected to the touch display substrate and the communication coil, and is configured to provide display signals and touch signals to the touch display substrate, and provide communication signals to the communication coil.

16. A display device, comprising: The touch display substrate according to any one of claims 11 to 14; as well as A driving circuit is connected to the touch display substrate and is configured to provide a display signal, a communication signal and a touch signal to the touch display substrate.

17. A method for driving a touch display substrate, the touch display substrate comprising a plurality of sub-pixels arranged in an array, the touch display substrate supporting a first frame frequency and a second frame frequency, the second frame frequency being greater than the first frame frequency, the period corresponding to the first frame frequency being a first frame period, and within a first frame period, the driving method comprising: In the picture refresh phase, each row of sub-pixels in the touch display substrate is charged row by row, and the charging time of a single row of sub-pixels is the charging time of a single row of sub-pixels at the second frame frequency; During the image holding stage, the touch display substrate is driven to perform touch detection.

18. The driving method according to claim 17, wherein: The ratio of the duration of the picture holding phase to the first frame period is greater than or equal to 0.3 and less than or equal to 0.

5.

19. The driving method according to claim 17 or 18, wherein: The communication coil of the touch display substrate is used to transmit communication signals, and the step of charging each row of sub-pixels in the touch display substrate row by row includes: In response to the triggering of multiple valid pulses in the clock signal, each row of sub-pixels in the touch display substrate is charged row by row. The clock signal is a periodic pulse signal, and the frequency of the periodic pulse signal is the pulse frequency. The even multiple of the pulse frequency is different from the frequency of the communication signal.

20. The driving method according to claim 19, wherein: The pulse frequency is greater than or equal to 10KHz and less than or equal to 12KHz; and / or The frequency of the subcarrier in the communication signal is greater than or equal to 800 KHz.

Images