Display driver, display screen and driving method thereof, display screen module and terminal

Abstract

The embodiment of the invention provides a display driver, a display screen, a driving method of the display screen, a display screen module and a terminal, relates to the technical field of electronics, and is used for improving the fingerprint sampling effect of the display screen module without affecting the display effect of the display screen module. A pixel circuit in the display screen has a specific local light spot control mode in the light emitting stage, and when fingerprint recognition is needed, the local light spot control mode is switched. For example, within an image frame, a light emitting phase is entered, and a local spot control mode is switched. The display driver adjusts the frequency of the initial light-emitting control signal to the first frequency, the frequency of the light-emitting control signal received by the corresponding pixel circuit is also the first frequency, and the first frequency has no relation with the frequency of the light-emitting control signal in the previous frame of the terminal and is a specific frequency. Therefore, the light-emitting unit has specific light-emitting brightness in the local light spot control mode. The specific light emitting brightness is determined in combination with the use scene, so that the problem of cross grains during fingerprint sampling can be improved.

Description

Technical Field

[0001] The present application relates to the field of electronic technology, and in particular to a display driver, a display screen and a driving method thereof, a display screen module, and a terminal. Background Art

[0002] With the development of display technology, high frame rate terminals with fingerprint recognition function have gradually become a market development trend. Terminals with high frame rate usually have the function of switching different screen refresh rates according to different usage scenarios. When using medium and high screen refresh rates, the screen freezes can be reduced. When using medium and low screen refresh rates, power consumption can be reduced. When entering the fingerprint unlocking interface, the display mode of local spot control is used to sample the fingerprint.

[0003] However, in current terminals, the fingerprint sampling effect has not reached a satisfactory level, especially in high frame rate terminals, where the fingerprint sampling effect is even worse. Summary of the invention

[0004] Embodiments of the present application provide a display driver, a display screen and a driving method thereof, a display screen module, and a terminal, which are used to improve the effect of fingerprint sampling.

[0005] In order to achieve the above objectives, this application adopts the following technical solutions:

[0006] In a first aspect of an embodiment of the present application, a display driver is provided, which is applied to a terminal, and the terminal includes a display screen. The display driver includes a start light-emitting control signal generating circuit, which is used to send a start light-emitting control signal required for the display screen to emit light to the display screen. The start light-emitting control signal generating circuit receives a local light spot control indication signal, switches to a local light spot control mode, and adjusts the frequency of the start light-emitting control signal to a first frequency. The first frequency is M times the base frequency, where M is an integer greater than 1; the first frequency is a common multiple of the screen refresh frequency supported by the display screen; the local light spot control indication signal is used to indicate that the brightness of the local area of ​​the display screen is greater than that of other areas. The local light spot area is, for example, an area that provides light source scanning for fingerprint recognition. After entering the fingerprint recognition mode, the start light-emitting control signal has a frequency change.

[0007] In the embodiment of the present application, when the terminal needs to perform fingerprint recognition, no matter which mode the previous frame is in, the start light control signal generating circuit will enter a specific local light spot control mode and output a start light control signal unique to the local light spot control mode. That is, from the full-screen light mode to the local light spot control mode, the start light control signal no longer uses the frequency of the previous frame, but has a frequency modulation action to change the frequency of the start light control signal to the first frequency. Then, in the local light spot control mode, the pixel circuit emits light under the drive of the light control signal with a frequency of the first frequency. By selecting the first frequency as a suitable value, the horizontal stripe problem existing in fingerprint sampling can be significantly improved.

[0008] In one possible implementation, the start light control signal generating circuit receives a first brightness indication signal, switches to a first brightness mode, and adjusts the frequency of the start light control signal to a second frequency; the start light control signal generating circuit receives a second brightness indication signal, switches to a second brightness mode, and adjusts the frequency of the start light control signal to a third frequency; the second frequency is greater than the base frequency, and the third frequency is less than the second frequency; the second frequency and the third frequency are both common multiples of the screen refresh frequency supported by the terminal; wherein the first brightness indication signal is used to indicate that the display screen emits light at a first brightness in full screen, and the second brightness indication signal is used to indicate that the display screen emits light at a second brightness in full screen.

[0009] The display driver provided in the embodiment of the present application has the ability to output the starting light control signal of the first frequency in the local light spot control mode, so that the fingerprint can have a better fingerprint collection effect when unlocking. The display driver also has the ability to output the starting light control signal of the second frequency in the first brightness mode and the starting light control signal of the third frequency in the second brightness mode. The third frequency is less than the second frequency, which can make the terminal have different display brightness, so that the terminal can be applied to the scene of variable frequency refresh display. When used in medium and high refresh rates, variable frequency can reduce screen freezes, and when used in medium and low refresh rates, variable frequency can reduce power consumption. While improving the fingerprint recognition effect, it does not affect the display effect of the terminal. In addition, by making the second frequency greater than the base frequency, the terminal can have a uniform brightness display effect in the first brightness mode. Furthermore, the second frequency and the third frequency are both common multiples of the screen refresh frequency supported by the terminal, which can improve the flickering problem caused by the display brightness change caused by the screen refresh frequency switching and entering the local light spot control mode.

[0010] In a possible implementation, the base frequency is the maximum screen refresh frequency supported by the terminal. The base frequency can change with the change of the terminal screen refresh frequency, and the first frequency can also change synchronously with the change of the terminal screen refresh frequency, which is applicable to various terminals.

[0011] In a possible implementation, the base frequency is 120 Hz. When the base frequency is 120 Hz, the display driver can be applied to a variety of current mainstream terminals and has strong adaptability.

[0012] In a possible implementation, in the local spot control mode, within an image frame, the start light control signal includes N pulses, and the widths of at least two of the N pulses are different; N is an integer greater than 1. By setting the pulse widths of the N pulses of the start light control signal to be not completely equal or completely unequal, the widths of the N pulses can be freely matched when the duty cycle remains unchanged, and the degree of freedom of the start light control signal can be increased. Increasing the degree of freedom of the start light control signal is conducive to increasing the duty cycle of the start light control signal to further improve the display effect.

[0013] In a possible implementation, the widths of the second to Nth pulses are equal. The pulse widths from the second pulse to the Nth pulse do not change, which can reduce the brightness fluctuation of the pixel circuit and improve the display effect.

[0014] In a possible implementation, the width of the first pulse of the start light control signal is equal to the width of the pulse of the start light control signal in the previous frame. After the display driver is applied to the terminal, the flicker of the terminal can be reduced.

[0015] In a possible implementation, the width of the first pulse of the start light-emitting control signal is greater than 40H, where H is the duration of writing the data voltage to a pixel circuit in a row of the display screen. By setting the width of the first pulse of the start light-emitting control signal to be greater than 40H, other stages before the light-emitting stage can be driven smoothly, and the complete function of the pixel circuit can be better realized.

[0016] In a possible implementation, the pulse width of the start light control signal is 20H-200H, where H is the duration of writing the data voltage to a row of pixel circuits in the display screen. This can meet the light brightness requirements without excessively increasing the proportion of the light-emitting stage in an image frame.

[0017] In one possible implementation, the display driver also includes a starting anode reset control signal generating circuit; the starting anode reset control signal generating circuit is used to generate a starting anode reset control signal, the frequency of the starting anode reset control signal is greater than or equal to 240hz, and is a common multiple of the screen refresh frequency supported by the terminal. The frequency of the starting anode reset control signal is greater than or equal to 240hz, which is the current mainstream high screen refresh frequency terminal, and is also a terminal with a more obvious horizontal stripe effect. When the display driver provided in the embodiment of the present application is applied to a terminal with a high screen refresh frequency, the terminal can have a better fingerprint collection effect.

[0018] In the second aspect of the embodiment of the present application, a display screen is provided, comprising a light-emitting control signal generating circuit and a pixel circuit; the light-emitting control signal generating circuit is used to receive the starting light-emitting control signal sent by the display driver, and output the light-emitting control signal to the pixel circuit. The pixel circuit comprises a light-emitting control circuit and a light-emitting unit. The light-emitting control circuit is used to receive the light-emitting control signal, and output a driving current to the light-emitting unit under the control of the light-emitting control signal, so as to drive the light-emitting unit to emit light; wherein, in an image frame, when entering the light-emitting stage, in the local light spot control mode, the frequency of the received light-emitting control signal is a light-emitting control signal adjusted to a first frequency, the first frequency is M times the base frequency, and M is an integer greater than 1; the first frequency is a common multiple of the screen refresh frequency supported by the display screen; in the local light spot control mode, the light-emitting brightness of a local area of ​​the display screen is greater than that of other areas. The beneficial effects of the pixel circuit provided in the second aspect of the embodiment of the present application are the same as the beneficial effects of the display driver provided in the first aspect, and will not be repeated here.

[0019] In a possible implementation, within an image frame, when entering the light-emitting stage and switching to the first brightness mode, the frequency of the received light-emitting control signal is the light-emitting control signal adjusted to the second frequency; within an image frame, when entering the light-emitting stage and switching to the second brightness mode, the frequency of the received light-emitting control signal is the light-emitting control signal adjusted to the third frequency; the second frequency is greater than the base frequency, and the third frequency is less than the second frequency; the second frequency and the third frequency are both common multiples of the screen refresh frequency supported by the display screen; wherein, in the first brightness mode, the display screen emits light at the first brightness in full screen; and in the second brightness mode, the display screen emits light at the second brightness in full screen.

[0020] In a possible implementation, the base frequency is the maximum screen refresh frequency supported by the display screen.

[0021] In a possible implementation, in the local light spot control mode, within one image frame, the light control signal includes N pulses, at least two of the N pulses have different widths; and N is an integer greater than 1.

[0022] In a possible implementation, the widths of the 2nd to Nth pulses are equal.

[0023] In a possible implementation, the width of a first pulse of the light emitting control signal is equal to the width of a pulse of the light emitting control signal in a previous frame.

[0024] In a possible implementation, the width of the first pulse of the light emitting control signal is greater than 40H, where H is the duration for writing the data voltage into the pixel circuit.

[0025] In a possible implementation, the pulse width of the light emitting control signal is 20H-200H, where H is the duration of writing the data voltage into the pixel circuit.

[0026] In one possible implementation, the display screen also includes an anode reset control signal generating circuit; the pixel circuit also includes an anode reset circuit; the anode reset control signal generating circuit is used to generate an anode reset control signal; the anode reset circuit is used to receive the anode reset control signal, and output the anode reset signal to the anode of the light-emitting unit under the control of the anode reset control signal; the frequency of the anode reset control signal is greater than or equal to 240 Hz, and is a common multiple of the screen refresh frequency supported by the display screen.

[0027] The third aspect of the embodiment of the present application provides a method for driving a display screen, wherein the display screen includes a light-emitting control signal generating circuit and a pixel circuit; the pixel circuit includes a light-emitting control circuit and a light-emitting unit; the driving method includes: in an image frame, entering the light-emitting stage, switching to the local light spot control mode, the light-emitting control signal generating circuit outputs a light-emitting control signal, and the frequency of the light-emitting control signal is adjusted to a first frequency, the first frequency is M times the base frequency, and M is an integer greater than 1; the first frequency is a common multiple of the screen refresh frequency supported by the display screen; the light-emitting control circuit outputs a driving current to the light-emitting unit under the control of the light-emitting control signal to drive the light-emitting unit to emit light; wherein, in the local light spot control mode, the light brightness of the local area of ​​the display screen is greater than that of other areas. The beneficial effects of the driving method of the pixel circuit provided in the third aspect of the embodiment of the present application are the same as the beneficial effects of the display driver provided in the first aspect, and will not be repeated here.

[0028] In a possible implementation, the driving method also includes: within an image frame, entering the light-emitting stage, switching to the first brightness mode, and adjusting the frequency of the light-emitting control signal to the second frequency; within an image frame, entering the light-emitting stage, switching to the second brightness mode, and adjusting the frequency of the light-emitting control signal to the third frequency; the second frequency is greater than the base frequency, and the third frequency is less than the second frequency; the second frequency and the third frequency are both common multiples of the screen refresh frequency supported by the display screen; wherein, in the first brightness mode, the display screen emits light at the first brightness in full screen; and in the second brightness mode, the display screen emits light at the second brightness in full screen.

[0029] In a possible implementation, the base frequency is the maximum screen refresh frequency supported by the display screen.

[0030] In one possible implementation, the base frequency is 120 Hz.

[0031] In a possible implementation, in the local light spot control mode, within one image frame, the light control signal includes N pulses, at least two of the N pulses have different widths; and N is an integer greater than 1.

[0032] In a possible implementation, the light emitting control signal includes N pulses, and the widths of the 2nd to Nth pulses are equal.

[0033] In a possible implementation, the width of a first pulse of the light emitting control signal is equal to the width of a pulse of the light emitting control signal in a previous frame.

[0034] In a possible implementation, the width of the first pulse of the light emitting control signal is greater than 40H, where H is the duration for writing the data voltage into the pixel circuit.

[0035] In a possible implementation, the pulse width of the light emitting control signal is 20H-200H, where H is the duration of writing the data voltage into the pixel circuit.

[0036] In a possible implementation, the display screen also includes an anode reset control signal generating circuit; the pixel circuit also includes an anode reset circuit; the driving method also includes: within an image frame, before the light-emitting stage, entering the anode reset stage, the anode reset control signal generating circuit generates an anode reset control signal; the anode reset circuit outputs the anode reset signal to the anode of the light-emitting unit under the control of the anode reset control signal; the frequency of the anode reset control signal is greater than or equal to 240 Hz and is a common multiple of the screen refresh frequency supported by the display screen.

[0037] According to a fourth aspect of an embodiment of the present application, a display driver is provided, which is applied to a terminal, and the terminal includes a display screen; the display driver includes a start light-emitting control signal generating circuit, and the start light-emitting control signal generating circuit is used to send a start light-emitting control signal required for the display screen to emit light to the display screen; wherein the start light-emitting control signal generating circuit receives a local light spot control indication signal, switches to a local light spot control mode, and adjusts the duty cycle of the start light-emitting control signal to be greater than the duty cycle of the start light-emitting control signal under the base frequency; the local light spot control indication signal is used to indicate that the light brightness of a local area of ​​the display screen is greater than that of other areas.

[0038] The display driver provided in the embodiment of the present application, when the terminal needs to perform fingerprint recognition, no matter which mode the previous frame is, the start light control signal generating circuit will enter a specific local light spot control mode, and output a start light control signal unique to the local light spot control mode. That is, from normal full-screen light emission to local light spot light emission, the start light control signal no longer uses the duty cycle of the previous frame, but has an action to adjust the duty cycle, and adjusts the duty cycle of the start light control signal to be greater than the duty cycle of the start light control signal at the base frequency. Then, in the local light spot control mode, the pixel circuit emits light under the drive of the light control signal. By selecting the duty cycle as a suitable value, the light brightness of the pixel circuit can be increased, which can significantly improve the horizontal stripe problem in fingerprint sampling.

[0039] In the fifth aspect of the embodiments of the present application, a display screen is provided, including a light-emitting control signal generating circuit and a pixel circuit; the light-emitting control signal generating circuit is used to receive the starting light-emitting control signal sent by the display driver, and output the light-emitting control signal to the pixel circuit; the pixel circuit includes a light-emitting control circuit and a light-emitting unit; the light-emitting control circuit is used to receive the light-emitting control signal, and under the control of the light-emitting control signal, output a driving current to the light-emitting unit to drive the light-emitting unit to emit light; wherein, in an image frame, when entering the light-emitting stage, in the local light spot control mode, the duty cycle of the received light-emitting control signal is greater than the duty cycle of the light-emitting control signal under the base frequency; in the local light spot control mode, the light brightness of the local area of ​​the display screen is greater than that of other areas. The beneficial effects of the pixel circuit provided in the fifth aspect of the embodiments of the present application are the same as the beneficial effects of the display driver provided in the fourth aspect, and will not be repeated here.

[0040] In the sixth aspect of the embodiments of the present application, a method for driving a display screen is provided, wherein the display screen includes a light-emitting control signal generating circuit and a pixel circuit; the pixel circuit includes: a light-emitting control circuit and a light-emitting unit; the driving method includes: in an image frame, entering the light-emitting stage, switching to the local light spot control mode, the light-emitting control signal generating circuit outputs a light-emitting control signal, and the duty cycle of the light-emitting control signal is adjusted to be greater than the duty cycle of the light-emitting control signal under the base frequency; the light-emitting control circuit outputs a driving current to the light-emitting unit under the control of the light-emitting control signal to drive the light-emitting unit to emit light; wherein, in the local light spot control mode, the light brightness of the local area of ​​the display screen is greater than that of other areas. The beneficial effects of the driving method of the pixel circuit provided in the sixth aspect of the embodiments of the present application are the same as the beneficial effects of the display driver provided in the fourth aspect, and will not be repeated here.

[0041] In a seventh aspect of an embodiment of the present application, a display screen module is provided, comprising a display driver and a display screen; the display driver comprises the display driver of any one of the first aspect or the fourth aspect, and / or the display screen comprises the display screen of any one of the second aspect or the fifth aspect; the display screen is used to receive a start light emission control signal sent by the display driver.

[0042] According to an eighth aspect of the embodiments of the present application, a terminal is provided, comprising a housing and a display screen module, wherein the display screen module is arranged inside the housing; the display screen module comprises the display screen module of the seventh aspect.

[0043] According to a ninth aspect of an embodiment of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program. When the computer program runs on a terminal, the terminal executes a driving method as in any one of the third aspect or the sixth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1AA schematic diagram of the layout of a terminal provided in an embodiment of the present application;

[0045] Figure 1B A schematic diagram of the layout of another terminal provided in an embodiment of the present application;

[0046] Figure 2 A schematic diagram of a sub-pixel topological structure provided in an embodiment of the present application;

[0047] Figure 3 A driving timing diagram of a pixel circuit provided in an embodiment of the present application;

[0048] Figure 4 A timing diagram of a light-emitting control signal at a light-emitting control signal terminal in a light-emitting stage provided in an embodiment of the present application;

[0049] Figure 5 A schematic diagram of a fingerprint sampling result for an embodiment of the present application;

[0050] Fig. 6A and Figure 6B A timing diagram of three start light emission control signals output by a display driver provided in an embodiment of the present application;

[0051] Figure 7 Another schematic diagram of fingerprint sampling results provided in an embodiment of the present application;

[0052] Figure 8 A timing diagram of a start light emission control signal in a local light spot control mode provided in an embodiment of the present application;

[0053] Figure 9A-9C A brightness change diagram corresponding to the timing of a starting anode reset control signal provided in an embodiment of the present application. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0055] In the following, the terms "second", "first", etc. are used only for convenience of description and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "second", "first", etc. may explicitly or implicitly include one or more of the feature. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0056] In addition, in the embodiments of the present application, directional terms such as "up", "down", "left" and "right" may be defined including but not limited to the orientation relative to the schematic placement of the components in the drawings. It should be understood that these directional terms may be relative concepts, which are used for relative description and clarification, and may change accordingly according to changes in the orientation of the components in the drawings.

[0057] In the embodiments of the present application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. In addition, the term "coupled" can be a direct electrical connection or an indirect electrical connection through an intermediate medium. The term "contact" can be a direct contact or an indirect contact through an intermediate medium.

[0058] In the embodiments of the present application, "and / or" describes the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B may be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0059] The present application embodiment provides a terminal. The terminal is, for example, a consumer electronic product with a display function, a home electronic product, a car-mounted electronic product, or a financial terminal product. Consumer electronic products include mobile phones, tablet computers, laptop computers, e-readers, personal computers (PCs), personal digital assistants (PDAs), desktop displays, smart wearable products (e.g., smart watches, smart bracelets), virtual reality (VR) terminals, augmented reality (AR) terminals, drones, etc. Home electronic products include smart door locks, televisions, remote controls, refrigerators, rechargeable small household appliances (e.g., soybean milk machines, sweeping robots), etc. Car-mounted electronic products include car navigators, car-mounted high-density digital video discs (DVDs), etc. Financial terminal products include automated teller machines (ATMs), self-service terminals, etc. The present application embodiment does not impose any special restrictions on the specific form of the above-mentioned terminals.

[0060] Take the mobile phone as an example. Figure 1AAs shown, the terminal 1 includes a display screen 10, a display driver 20 and a system on chip (SOC). Figure 1A The terminal 1 is taken as a straight-screen mobile phone as an example for illustration, which is only an illustration in the embodiment of the present application.

[0061] In some embodiments, the display screen 10 may be an organic light emitting diode (OLED) display screen, which can realize self-luminescence. Alternatively, in other embodiments, the display screen 10 may be a liquid crystal display (LCD). In this case, the terminal further includes a backlight module for providing a light source to the display screen 10.

[0062] For any of the above display screens 10, the display screen 10 includes an active display area (AA) and a non-display area BB located around the active display area AA. The active display area AA is used to display images, and the active display area AA includes a plurality of sub pixels (SP), each of which is provided with a pixel circuit 11.

[0063] In the present application, the pixel circuits 11 are described by taking a matrix arrangement as an example. The pixel circuits 11 arranged in a row along the horizontal direction X are called pixel circuits 11 in the same row, and the pixel circuits 11 arranged in a row along the vertical direction Y are called pixel circuits 11 in the same column.

[0064] The display driver 20 is used to provide the display screen 10 with scanning signals and data signals required for emitting light. The signals sent by the display driver 20 will be described in detail below in conjunction with the structure of the pixel circuit 11 .

[0065] The display driver 20 may be coupled to the SOC via a mobile industry processor interface (MIPI) interface. Of course, the display driver 20 may also be coupled to the SOC via other serial / deserial (SerDes) high-speed interfaces.

[0066] As the screen refresh frequency changes, the display driver 20 sends a tearing effect (TE) signal to the SOC, and the SOC sends image data to the display driver 20 according to the frequency of the TE signal. The TE signal can make the frequency at which the SOC sends image data consistent with the frequency at which the display driver 20 needs to receive image data, so that the actual screen refresh frequency can respond to the image refresh frequency of the SOC (that is, the theoretical screen refresh frequency) in a timely manner.

[0067] In some embodiments, the terminal 1 further includes a fingerprint sensor 30, which may be, for example, an optical image sensor that uses the self-luminescence of the display screen 10 as a light source, and is used to enable the terminal 1 to have a fingerprint recognition function. The fingerprint sensor 30 may be provided separately from the display screen 10, which is called a separate under-screen optical fingerprint sensor. The fingerprint sensor 30 may also be integrated into the display screen 10, which is called an integrated in-screen optical fingerprint sensor.

[0068] Take the mobile phone as an example. Figure 1B As shown, the terminal 1 includes a display screen 10, a display driver 20 and a SOC. Figure 1B The terminal 1 is taken as an example of a folding screen mobile phone, which is only an illustration in the embodiment of the present application.

[0069] The display screen 10 includes two effective display areas AA, each of which is provided with a plurality of pixel circuits 11 arranged in an array. Figure 1B A pixel circuit 11 is taken as an example for illustration.

[0070] In some embodiments, the pixel circuit 11 generally includes a driving circuit composed of a plurality of transistors and a light-emitting unit. The driving circuit generates a driving current to drive the light-emitting unit to emit light, so as to realize the light-emitting of the pixel circuit 11 .

[0071] Oxide thin-film transistor (Oxide TFT) refers to a thin-film transistor whose semiconductor active layer material is oxide, which has the characteristic of low leakage current. Low-temperature polysilicon thin-film transistor (LTPS TFT) refers to a thin-film transistor whose semiconductor active layer material is low-temperature polysilicon, which has the characteristic of high mobility. The on-current of LTPS TFT is high, but the leakage current is also high. Therefore, it is suitable for working in high-frequency state. However, the power consumption of high-frequency working state is large, which makes it difficult to meet the demand of low power consumption of products. Compared with LTPS TFT, Oxide TFT has lower leakage current and moderate on-current, which can effectively save power consumption in low-frequency applications. Therefore, the combination of LTPS TFT and Oxide TFT as the driving circuit of the pixel circuit can simultaneously realize high refresh rate, low refresh rate and non-sensing switching between different refresh rates, meet the demand of dynamic frame change, and have broad application prospects in OLED display screens.

[0072] Figure 2 A schematic diagram of a sub-pixel topological structure provided in an embodiment of the present application.

[0073] In some embodiments, Figure 2As shown, the pixel circuit 11 includes an anode reset circuit 111 , a second node initialization circuit 112 , a first node initialization circuit 113 , a writing and threshold compensation circuit 114 , a light emitting control circuit 115 and a light emitting unit 116 . Figure 2 The pixel circuit 11 shown is only for illustration and is not intended to be limiting.

[0074] The anode reset circuit 111 is coupled to the first initialization voltage terminal Vinit1, the first control signal terminal S1 and the anode of the light-emitting unit 116, and is used to transmit the first initialization voltage of the first initialization voltage terminal Vinit1 to the anode of the light-emitting unit 116 under the control of the first control signal of the first control signal terminal S1, so as to initialize the anode of the light-emitting unit 116.

[0075] The second node initialization circuit 112 is coupled to the second initialization voltage terminal Vinit2, the first control signal terminal S1 and the second node N2, and is used to transmit the second initialization voltage of the second initialization voltage terminal Vinit2 to the second node N2 under the control of the first control signal of the first control signal terminal S1 to initialize the second node N2.

[0076] The second node initialization circuit 112 may not be coupled to the same control signal terminal as the anode reset circuit 111. The second node initialization circuit 112 is coupled to the fifth control signal terminal alone and is controlled by the fifth control signal of the fifth control signal terminal. Figure 2 The figure is for illustration only.

[0077] The first node initialization circuit 113 is coupled to the third initialization voltage terminal Vinit3, the second control signal terminal S2, the third control signal terminal S3, the first node N1 and the second node N2, and is used to transmit the third initialization voltage of the third initialization voltage terminal Vinit3 to the first node N1 and the second node N2 under the control of the second control signal of the second control signal terminal S2 and the third control signal of the third control signal terminal S3, so as to initialize the first node N1 and the second node N2.

[0078] The write and threshold compensation circuit 114 is coupled to the fourth control signal terminal S4, the third control signal terminal S3, the second node N2, the first power supply voltage terminal ELVDD and the data voltage terminal Vdata, and is used to transmit the data voltage of the data voltage terminal Vdata to the write and threshold compensation circuit 114 for data writing and threshold compensation under the control of the fourth control signal of the fourth control signal terminal S4 and the third control signal of the third control signal terminal S3.

[0079] The light emitting control circuit 115 is coupled to the light emitting control signal terminal EM, the first power supply voltage terminal ELVDD, the write and threshold compensation circuit 114 and the light emitting unit 116, and is used to provide a driving current to the light emitting unit 116 under the control of the light emitting control signal em provided by the light emitting control signal terminal EM.

[0080] The light emitting unit 116 is coupled to the second power supply voltage terminal ELVSS, and is configured to emit light under the driving of the driving current.

[0081] In the embodiment of the present application, the first power supply voltage terminal ELVDD is a high-level power supply voltage terminal, and the second power supply voltage terminal ELVSS is a low-level power supply voltage terminal for illustration, but this is not limiting.

[0082] In some embodiments, reference Figure 2 , the anode reset circuit 111 includes a seventh transistor T7, the second node initialization circuit 112 includes an eighth transistor T8, the first node initialization circuit 113 includes a fourth transistor T4 and a third transistor T3, the write and threshold compensation circuit 114 includes a second transistor T2, a first transistor T1, a third transistor T3, and a storage capacitor Cst, and the light control circuit 115 includes a fifth transistor T5 and a sixth transistor T6. The first transistor T1 is a driving transistor, and the remaining transistors are switch transistors. The first node initialization circuit 113 and the write and threshold compensation circuit 114 share the third transistor T3. The light emitting unit 116 is, for example, an OLED.

[0083] In the following description, the control electrode of the transistor may be, for example, the gate electrode of the transistor, and the first electrode of the transistor and the second electrode of the transistor may be the source electrode and the drain electrode of the transistor, respectively. This is explained here and will not be further explained below.

[0084] A control electrode of the fourth transistor T4 is coupled to the second control signal terminal S2 , a first electrode of the fourth transistor T4 is coupled to the third initialization voltage terminal Vinit3 , and a second electrode of the fourth transistor T4 is coupled to the fourth node N4 .

[0085] A control electrode of the third transistor T3 is coupled to the third control signal terminal S3 , a first electrode of the third transistor T3 is coupled to the fourth node N4 , and a second electrode of the third transistor T3 is coupled to the first node N1 .

[0086] A control electrode of the second transistor T2 is coupled to the fourth control signal terminal S4 , a first electrode of the second transistor T2 is coupled to the data voltage terminal Vdata, and a second electrode of the second transistor T2 is coupled to the third node N3 .

[0087] The control electrode of the first transistor T1 is coupled to the first node N1, the first electrode of the first transistor T1 is coupled to the third node N3, the second electrode of the first transistor T1 is coupled to the second node N2, and the second node N2 is also coupled to the fourth node N4.

[0088] One end of the storage capacitor Cst is coupled to the first node N1 , and the other end of the storage capacitor Cst is coupled to the first power voltage terminal ELVDD.

[0089] A control electrode of the fifth transistor T5 is coupled to the light emitting control signal terminal EM, a first electrode of the fifth transistor T5 is coupled to the first power supply voltage terminal ELVDD, and a second electrode of the fifth transistor T5 is coupled to the third node N3.

[0090] A control electrode of the sixth transistor T6 is coupled to the light emitting control signal terminal EM, a first electrode of the sixth transistor T6 is coupled to the second node N2 , and a second electrode of the sixth transistor T6 is coupled to the anode of the light emitting unit 116 .

[0091] A control electrode of the seventh transistor T7 is coupled to the first control signal terminal S1 , a first electrode of the seventh transistor T7 is coupled to the first initialization voltage terminal Vinit1 , and a second electrode of the seventh transistor T7 is coupled to the anode of the light emitting unit 116 .

[0092] A control electrode of the eighth transistor T8 is coupled to the first control signal terminal S1 , a first electrode of the eighth transistor T8 is coupled to the second initialization voltage terminal Vinit2 , and a second electrode of the eighth transistor T8 is coupled to the second node N2 .

[0093] For example, in the pixel circuit 11, the third transistor T3 and the fourth transistor T4 are oxide TFTs, which are N-type transistors and are turned on under the control of a high-level signal. The third transistor T3 and the fourth transistor T4 can also be other types of transistors, which are not limited in the embodiments of the present application. The first transistor T1, the second transistor T2, the fifth transistor T5, the sixth transistor T6, the seventh transistor T7 and the eighth transistor T8 are LTPS TFTs, which are P-type transistors and are turned on under the control of a low-level signal. The first transistor T1, the second transistor T2, the fifth transistor T5, the sixth transistor T6, the seventh transistor T7 and the eighth transistor T8 can also be other types of transistors, which are not limited in the embodiments of the present application.

[0094] Figure 3 A driving timing diagram of a pixel circuit provided in an embodiment of the present application.

[0095] Combination Figure 2 and Figure 3 As shown, the light emitting process of the pixel circuit 11 in one frame can be divided into an initialization phase t1, a threshold compensation phase t2, a light emitting phase t3, and an anode reset phase t4.

[0096] In the initialization phase t1:

[0097] The second control signal of the second control signal terminal S2 and the third control signal of the third control signal terminal S3 change from low level to high level and then from high level to low level. Thus, the fourth transistor T4 and the third transistor T3 change from off to on and then from on to off.

[0098] The first control signal of the first control signal terminal S1, the fourth control signal of the fourth control signal terminal S4 and the light control signal em of the light control signal terminal EM all maintain a high level, so the seventh transistor T7, the eighth transistor T8, the second transistor T2, the fifth transistor T5 and the sixth transistor T6 all remain in the off state.

[0099] In the initialization stage t1, the first transistor T1, the third transistor T3 and the fourth transistor T4 are turned on respectively, and the voltage control of the fourth node N4, the voltage control of the second node N2 and the voltage control of the first node N1 are realized. Since the third transistor T3 and the fourth transistor T4 are respectively used as switch tubes, the first node N1 is electrically connected to the control electrode of the first transistor T1, and the second node N2 is electrically connected to the fourth node N4, so in the initialization stage t1, the control electrode voltage control of the first transistor T1, the voltage control of the node N1, the voltage control of the second node N2 and the voltage control of the fourth node N4 are realized, so that the control electrode voltage of the first transistor T1, the voltage of the first node N1, the voltage of the second node N2 and the voltage of the fourth node N4 are respectively the third initialization voltage of the third initialization voltage terminal Vinit3, that is, the control electrode voltage of the first transistor T1, the voltage of the first node N1, the voltage of the second node N2 and the voltage of the fourth node N4 are reset.

[0100] In the threshold compensation phase t2:

[0101] The first control signal of the first control signal terminal S1 changes from high level to low level, and then changes from low level to high level. Thus, the second transistor T2 changes from off to on, and then changes from on to off. The third control signal of the third control signal terminal S3 changes from low level to high level, and then changes from high level to low level. Thus, the third transistor T3 changes from off to on, and then changes from on to off.

[0102] The first control signal of the first control signal terminal S1 and the light control signal em of the light control signal terminal EM both maintain a high level, and the second control signal of the second control signal terminal S2 maintains a low level. Therefore, the seventh transistor T7, the eighth transistor T8, the fifth transistor T5, the sixth transistor T6 and the fourth transistor T4 all maintain an off state.

[0103] In the threshold compensation stage t2, transistors T2, T3 and T1 are turned on respectively, so that the data voltage of the data voltage terminal Vdata is stored in the storage capacitor Cst, and the writing of the data voltage is completed. The threshold voltage of the first transistor T1 is compensated. The compensation process of the threshold voltage of the first transistor T1 can be considered as the process of the first transistor T1 changing from the on state to the off state.

[0104] In the light-emitting phase t3:

[0105] The light emitting control signal em changes from high level to low level, and then changes from low level to high level. Thus, the sixth transistor T6 and the fifth transistor T5 change from off to on, and then from on to off.

[0106] The second control signal of the second control signal terminal S2 and the third control signal of the third control signal terminal S3 respectively maintain a low level, and the fourth transistor T4 and the third transistor T3 both maintain an off state. The first control signal of the first control signal terminal S1 and the fourth control signal of the fourth control signal terminal S4 respectively maintain a high level, and the seventh transistor T7, the eighth transistor T8 and the second transistor T2 all maintain an off state.

[0107] In the light emitting stage t3 , the fifth transistor T5 , the first transistor T1 , and the sixth transistor T6 are turned on respectively to transmit the driving current to the light emitting unit 116 , and the light emitting unit 116 emits light under the driving current.

[0108] Anode reset phase t:

[0109] The first control signal of the first control signal terminal S1 changes from high level to low level, and then changes from low level to high level. Thus, the seventh transistor T7 and the eighth transistor T8 change from off to on, and then from on to off.

[0110] The second control signal of the second control signal terminal S2 and the third control signal of the third control signal terminal S3 always maintain a low level, and the fourth control signal of the fourth control signal terminal and the light-emitting control signal em of the light-emitting control signal terminal EM always maintain a high level. The third transistor T3, the fourth transistor T4, the second transistor T2, the fifth transistor T5 and the sixth transistor T6 all maintain an off state.

[0111] In the anode reset stage t, the seventh transistor T7 and the eighth transistor T8 are turned on, realizing the control of the voltage of the second node N2 and the control of the anode voltage of the light-emitting unit 116, so that the voltage of the second node N2 is the second initialization voltage of the second initialization voltage terminal Vinit2, and the voltage of the anode of the light-emitting unit 116 is the first initialization voltage of the first initialization voltage terminal Vinit1, realizing the resetting of the second node N2 and the anode voltage of the light-emitting unit 116.

[0112] In some embodiments, the terminal 1 does not have a threshold compensation phase t2 for each frame, and some terminals 1 have a threshold compensation phase t2 for one frame and a holding phase for one frame, and the holding phase holds the data signal of the previous frame. In the present application, the second initialization voltage of the second initialization voltage terminal Vinit2 can be dynamically adjusted to achieve different voltages in the light-emitting phase t3 and the holding phase.

[0113] In one image frame, an anode reset stage t can be performed before each of the initialization stage t1, the threshold compensation stage t2, and the light-emitting stage t3. An anode reset can also be performed before one or both of the initialization stage t1, the threshold compensation stage t2, and the light-emitting stage t3. Figure 3 The driving timing diagram shown is illustrated by taking an anode reset performed once before the initialization phase t1 , the threshold compensation phase t2 , and the light-emitting phase t3 as an example.

[0114] The following is a schematic description of the origins of the control signals received by the first control signal terminal S1 , the second control signal terminal S2 , the third control signal terminal S3 , the fourth control signal terminal S4 , and the light emitting control signal terminal EM in the pixel circuit 11 .

[0115] like Figure 1A and Figure 1B As shown, in some embodiments, the display screen 10 further includes an em generating circuit 12 , and the em generating circuit 12 is used to transmit a light emitting control signal em to the light emitting control signal terminals EM of the plurality of pixel circuits 11 in the display screen 10 .

[0116] In some embodiments, Figure 1A As shown, the em generation circuit 12 includes a plurality of cascaded EM array gate driver on array (GOA) units, and each EM GOA unit is used to provide a light emission control signal em for a row of pixel circuits 11. Two or more em generation circuits 12 may also be provided, and each em generation circuit 12 is used to provide a light emission control signal em for part of the pixel circuits 11 in a row.

[0117] The EM GOA unit of the first stage receives the start light control signal STV-em and outputs the light control signal em. Starting from the second stage, the EM GOA unit of each stage receives the light control signal em output by the EM GOA unit of the previous stage and outputs the light control signal em corresponding to the EM GOA unit of the current stage. Taking the effective display area AA including 10 rows of pixel circuits 11 as an example, the light control signal em generated by the em generation circuit 12 includes light control signals em1 to em10.

[0118] In some embodiments, the start light emission control signal STV-em is provided by the display driver 20. The em generation circuit 12 is used to receive the start light emission control signal STV-em sent by the display driver 20 and generate the light emission control signal em required by the pixel circuit 11.

[0119] like Figure 1A and Figure 1B As shown, in some embodiments, the display screen 10 further includes a first control signal generating circuit (or understood as an anode reset control signal generating circuit) 13. The first control signal generating circuit 13 has a similar structure to the em generating circuit 12 and is used to transmit a first control signal s1 to each row of pixel circuits 11. The first control signal s1 generated by the first control signal generating circuit 13 includes a first control signal s1(1) to a first control signal s1(n), where n is the number of rows of pixel circuits 11 in the effective display area AA. The starting first control signal STV-s1 required by the first control signal generating circuit 13 is provided by the display driver 20.

[0120] For example, Figure 1A As shown, the first control signal s1 required by a row of pixel circuits 11 is generated by a first control signal generating circuit 13 located at one side of the effective display area AA.

[0121] Or, for example, Figure 1B As shown, the first control signal s1 required by a row of pixel circuits 11 is generated by the first control signal generating circuits 13 located on both sides of the effective display area AA. Each first control signal generating circuit 13 provides the first control signal s1 for, for example, half a row of pixel circuits 11.

[0122] like Figure 1A and Figure 1B As shown, the display screen 10 further includes a second control signal generating circuit 14. The second control signal generating circuit 14 has a similar structure to the em generating circuit 12 and is used to transmit a second control signal s2 to each row of pixel circuits 11. The second control signal s2 generated by the second control signal generating circuit 14 includes a second control signal s2(1) to a second control signal s2(n), where n is the number of rows of pixel circuits 11 in the effective display area AA. The start second control signal STV-s2 required by the second control signal generating circuit 14 is provided by the display driver 20.

[0123] like Figure 1B As shown, the second control signals s2 in different effective display areas AA in the display screen 10 can be provided by the same second control signal generating circuit 14. The second control signals s2 in different effective display areas AA in the display screen 10 can also be provided by different second control signal generating circuits 14.

[0124] like Figure 1A and Figure 1BAs shown, the display screen 10 further includes a third control signal generating circuit 15. The third control signal generating circuit 15 has a similar structure to the em generating circuit 12 and is used to transmit a third control signal s3 to each row of pixel circuits 11. The third control signal s3 generated by the third control signal generating circuit 15 includes a third control signal s3(1) to a third control signal s3(n), where n is the number of rows of pixel circuits 11 in the effective display area AA. The starting third control signal STV-s3 required by the third control signal generating circuit 15 is provided by the display driver 20.

[0125] The display screen 10 further includes a fourth control signal generating circuit 16. The fourth control signal generating circuit 16 has a structure similar to that of the em generating circuit 12 and is used to transmit a fourth control signal s4 to each row of pixel circuits 11. The fourth control signal s4 generated by the fourth control signal generating circuit 16 includes a fourth control signal s4(1) to a fourth control signal s4(n), where n is the number of rows of pixel circuits 11 in the effective display area AA. The start fourth control signal STV-s4 required by the fourth control signal generating circuit 16 is provided by the display driver 20.

[0126] Figure 1A and Figure 1B The structures of the em generating circuit 12, the first control signal generating circuit 13, the second control signal generating circuit 14, the third control signal generating circuit 15 and the fourth control signal generating circuit 16 shown in the figure and their setting positions in the display screen 10 are only for illustration and are not limited in any way.

[0127] At present, high frame rate terminals with fingerprint recognition function usually include low brightness mode and high brightness mode when emitting light. In low brightness mode, the whole screen of terminal 1 emits light with the same brightness, and the brightness of the light emission is lower than or equal to the preset brightness. In high brightness mode, the whole screen of terminal 1 emits light with the same brightness, and the brightness of the light emission is higher than the preset brightness. The preset brightness can be, for example, 90nit, and the preset brightness can also be other values, 90nit is only an illustration.

[0128] Figure 4 A timing diagram of a light-emitting control signal at a light-emitting control signal end in a light-emitting stage provided in an embodiment of the present application.

[0129] like Figure 4 As shown, the light control signal em of the light control signal terminal EM includes a second frequency f2 corresponding to the low brightness mode and a third frequency f3 corresponding to the high brightness mode. During fingerprint recognition, the light control signal em has no corresponding frequency and uses the frequency of the light control signal em of the previous frame.

[0130] For example, in the low brightness mode, the second frequency f2 of the light emitting control signal em of the light emitting control signal terminal EM is greater than or equal to 1440 Hz, and the number of pulses is greater than or equal to 12. Figure 4 The second frequency f2 of the light emitting control signal em is equal to 1440 Hz.

[0131] In the high brightness mode, the third frequency f3 of the light emitting control signal em of the light emitting control signal terminal EM is less than or equal to 360 Hz, and the number of pulses is less than or equal to 3. Figure 4 The third frequency f3 of the light emitting control signal em is equal to 360 Hz.

[0132] The start light emitting control signal STV-em provided by the display driver 20 to the em generating circuit 12 only includes the start light emitting control signal STV-em in the high brightness mode and the start light emitting control signal STV-em in the low brightness mode.

[0133] When fingerprint recognition is required, the light control signal em uses the frequency of the previous frame. For example, from low brightness mode to fingerprint recognition mode, the frequency of the light control signal em in the previous frame is 1440hz, and the frequency of the light control signal em during fingerprint recognition is still 1440hz. From high brightness mode to fingerprint recognition mode, the frequency of the light control signal em in the previous frame is 360hz, and the frequency of the light control signal em during fingerprint recognition is still 360hz.

[0134] However, since the pulse of the light control signal em has a fixed periodic intensity drop, the light brightness has an inherent periodic drop. This causes that when the fingerprint signal needs to be collected by exposure, some exposure positions will encounter a drop in brightness, which will cause Figure 5 The horizontal stripes pointed by the arrow in the middle affect the fingerprint collection performance. Especially when entering the fingerprint recognition mode from the high brightness mode, the interference of the horizontal stripes is more obvious. Figure 5 A schematic diagram of a fingerprint sampling result illustrating an embodiment of the present application.

[0135] The embodiment of the present application innovates the EM driving solution, thereby improving the problem of horizontal stripe interference in fingerprint sampling without affecting the display effect and enhancing the fingerprint sampling effect.

[0136] The embodiment of the present application provides a display driver 20, which is applied to the above-mentioned terminal 1. The display driver 20 includes a start light emission control signal (STV-em) generating circuit, and the STV-em generating circuit is used to generate the start light emission control signal STV-em required for the terminal 1 to emit light. The em generating circuit 12 receives the start light emission control signal STV-em and outputs the light emission control signal em to the pixel circuit 11 row by row.

[0137] Fig. 6A and Figure 6B A timing diagram of three start light emission control signals STV-em output by a display driver 20 provided in an embodiment of the present application.

[0138] like Fig. 6A and Figure 6B As shown, after receiving the local light spot control indication signal, the STV-em generating circuit switches to the local light spot control mode. Regardless of the frequency of the start light control signal STV-em of the previous frame, the frequency of the start light control signal STV-em is adjusted to the first frequency f1.

[0139] In the embodiment of the present application, when the terminal 1 needs to perform fingerprint recognition, no matter which mode the previous frame is, the STV-em generation circuit will enter a specific local light spot control mode and output a start light control signal STV-em unique to the local light spot control mode. That is, from full-screen normal light emission to local light spot light emission, the start light control signal STV-em no longer uses the frequency of the previous frame, but has a frequency modulation action to change the frequency of the start light control signal STV-em to the first frequency f1.

[0140] The local light spot control indication signal is used to indicate that the local area in the display area AA of the display screen 10 emits light at a brightness greater than that of other areas. The position of the local light spot area in the display area AA can be set in combination with the actual use scenario of the terminal 1. The local light spot area matches the setting position of the fingerprint sensor 30, and is used to provide a light source scan for the fingerprint sensor 30.

[0141] The embodiment of the present application does not limit the origin of the local light spot control indication signal. The local light spot control indication signal can be triggered by a touch layer notification, or the fingerprint sensor 30 and the display screen 10 can have a communication interface, which can identify the timing of screen light emission in advance and send out a local light spot control indication signal.

[0142] Figure 7 A schematic diagram of a fingerprint sampling result provided in an embodiment of the present application.

[0143] By selecting the first frequency f1 as a suitable value, such as Figure 7 As shown, the horizontal stripe problem in fingerprint sampling can be significantly improved.

[0144] In some embodiments, the first frequency f1 is a common multiple of screen refresh frequencies supported by the terminal 1 .

[0145] Give the definitions of common multiples and least common multiples: Common multiples refer to two or more natural numbers that have the same multiples. The smallest common multiple is called the least common multiple of these integers.

[0146] For example, the screen refresh frequencies supported by terminal 1 include 10 Hz, 20 Hz, 30 Hz, 60 Hz, 90 Hz, and 120 Hz, the lowest common multiple of the screen refresh frequencies supported by terminal 1 is 360 Hz, and the first frequency f1 of the start light control signal STV-em is an integer multiple of 360 Hz.

[0147] In some embodiments, the first frequency f1 is M times the base frequency, where M is an integer greater than 1. For example, the value of M is 2, 3, 4, 5, 6, etc. The base frequency can be selected in combination with the driving adjustment capability of the terminal 1 .

[0148] For example, the base frequency is the maximum screen refresh frequency supported by the terminal 1. The first frequency f1 is more than twice the maximum screen refresh frequency supported by the terminal 1.

[0149] The first frequency f1 can be divided by each screen refresh frequency. A pulse unit of the start light emitting control signal STV-em is used as the minimum repeating unit of the start light emitting control signal STV-em. When the screen refresh frequency of the terminal 1 changes, only the number of pulse units changes, but the average brightness obtained by dividing the total brightness by the number of pulse units remains unchanged. Therefore, no matter how the screen refresh frequency changes, the light emitting brightness of the pixel circuit 11 is always the same, so as to improve the display effect.

[0150] Optionally, the screen refresh frequencies supported by the terminal 1 include 10 Hz, 20 Hz, 30 Hz, 60 Hz, 90 Hz, and 120 Hz, and the base frequency is 120 Hz. For example, the base frequency is 120 Hz, the first frequency f1 is 120*M hz, and the first frequency f1 can be 360 ​​Hz, 720 Hz, 1080 Hz, 1440 Hz, and the like. Fig. 6A In the example, the base frequency is 120 Hz, including 3 pulses, and the first frequency f1 is 1440 Hz, including 12 pulses. Figure 6B Here, the base frequency is 120 Hz, including 3 pulses, and the first frequency f1 is 2880 Hz, including 24 pulses.

[0151] Alternatively, the screen refresh frequencies supported by the terminal 1 include 10 Hz, 20 Hz, 30 Hz, 60 Hz, 80 Hz, and 120 Hz, and the base frequency is an integer multiple of 240 Hz. For example, the base frequency is 240 Hz, the first frequency f1 is 240*M hz, and the first frequency f1 can be 480 Hz, 720 Hz, and the like.

[0152] Alternatively, the screen refresh frequencies supported by the terminal 1 include 10 Hz, 20 Hz, 30 Hz, 60 Hz, 120 Hz, and 144 Hz, and the base frequency is 144 Hz. For example, the base frequency is 144 Hz, the first frequency f1 is 144*M hz, and the first frequency f1 can be 288 Hz, 432 Hz, and the like.

[0153] In some embodiments, reference Fig. 6A The STV-em generating circuit receives the first brightness indication signal, switches to the first brightness mode, and adjusts the frequency of the start light emitting control signal STV-em to the second frequency f2.

[0154] The STV-em generating circuit receives the second brightness indication signal, switches to the second brightness mode, and adjusts the frequency of the start light emitting control signal STV-em to the third frequency f3.

[0155] The first brightness indication signal is used to indicate that the display screen 10 emits light at a first brightness in full screen, and the second brightness indication signal is used to indicate that the display screen 10 emits light at a second brightness in full screen. For example, the first brightness is lower than or equal to the preset brightness, and the first brightness indication signal can be understood as a low brightness indication signal. The second brightness is higher than the preset brightness, and the second brightness indication signal can be understood as a high brightness indication signal. The low brightness in the embodiment of the present application is relative to the high brightness, and the preset brightness of the watershed between low brightness and high brightness is not specifically limited, and can be set in combination with the application scenario. The first brightness indication signal and the second brightness indication signal can, for example, be sent via a system on chip (SOC).

[0156] In the display driver 20 provided in the embodiment of the present application, the start light control signal STV-em sent by the STV-em generation circuit includes three modes. In the local spot control mode, the frequency of the start light control signal STV-em is the first frequency f1. In the first brightness mode, the frequency of the start light control signal STV-em is the second frequency f2. In the second brightness mode, the frequency of the start light control signal STV-em is the third frequency f3.

[0157] The first frequency f1 is M times the base frequency, the second frequency f2 is greater than the base frequency, and the third frequency f3 is less than the second frequency f2. For example, the first frequency f1 is greater than the third frequency f3, and there is no limitation on the magnitude relationship between the first frequency f1 and the second frequency f2. The second frequency f2 and the third frequency f3 are both common multiples of the screen refresh frequency supported by the terminal 1.

[0158] For example, the base frequency is 120 Hz, including 1 pulse. Fig. 6A As shown, the first frequency f1 is 1440 Hz, including 12 pulses. The second frequency f2 is 1440 Hz, including 12 pulses. The third frequency f3 is 360 Hz, including 3 pulses.

[0159] Or, if Figure 6B As shown, the first frequency f1 is 2880 Hz, including 24 pulses, the second frequency f2 is 1440 Hz, including 12 pulses, and the third frequency f3 is 720 Hz, including 6 pulses.

[0160] The display driver 20 provided in the embodiment of the present application has the ability to output the starting light control signal STV-em of the first frequency f1 in the local light spot control mode, so that a better fingerprint collection effect can be achieved when the fingerprint is unlocked. The display driver 20 also has the ability to output the starting light control signal STV-em of the second frequency f2 in the first brightness mode and the starting light control signal STV-em of the third frequency f3 in the second brightness mode, and can be applied to the scene of variable frequency refresh display. When used in medium and high refresh rates, variable frequency can reduce screen freezes, and when used in medium and low refresh rates, variable frequency can reduce power consumption. While improving the fingerprint recognition effect, it does not affect the display effect of the terminal 1. The second frequency f2 and the third frequency f3 are both common multiples of the screen refresh frequency supported by the terminal 1, which can improve the display flickering problem caused by switching the screen refresh frequency and entering the local light spot control mode.

[0161] In some embodiments, Fig. 6A As shown, in the local light spot control mode, within one image frame, the pulse widths of the start light emission control signals STV-em are equal.

[0162] The pulse width in the embodiment of the present application refers to the width of the effective pulse. For example, if the start light control signal STV-em is high level effective, the pulse width is the width of the high level pulse of the start light control signal STV-em. If the start light control signal STV-em is low level effective, the pulse width is the width of the low level pulse of the start light control signal STV-em.

[0163] For example, the pulse width of the start light emitting control signal STV-em is 20H-200H.

[0164] H is the duration of writing the data voltage to a pixel circuit 11 in a row of the display screen 10, that is, the duration of the effective pulse of the fourth control signal at the fourth control signal terminal S4 in an image frame. Figure 3 The duration corresponding to one H is indicated in FIG.

[0165] For example, the pulse width of the start light emitting control signal STV-em may be 30H, 50H, 70H, 100H, 130H, 150H, 180H, etc.

[0166] This can meet the luminous brightness requirements without excessively increasing the proportion of the luminous stage in an image frame.

[0167] Figure 8 A timing diagram of a start light emission control signal STV-em in a local light spot control mode provided by an embodiment of the present application.

[0168] In other embodiments, Figure 8 As shown, in the local spot control mode, within one image frame, the start light control signal STV-em includes N pulses, and the widths of at least two pulses in the N pulses are not equal. N is an integer greater than 1, for example, N is 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0169] By setting the pulse widths of the N pulses of the start light emitting control signal STV-em to be not completely equal or completely unequal, the widths of the N pulses can be freely matched under the condition that the duty cycle remains unchanged, and the degree of freedom of the start light emitting control signal STV-em can be increased. After the degree of freedom of the start light emitting control signal STV-em is increased, it is beneficial to increase the duty cycle of the start light emitting control signal STV-em, so as to further improve the display effect.

[0170] For example, the widths of the N pulses included in the start light emitting control signal STV-em are all different.

[0171] Or, for example, among the N pulses included in the start light emitting control signal STV-em, some pulses have the same width.

[0172] For example, the widths of the 2nd to Nth pulses are equal and not equal to the width of the first pulse.

[0173] The pulse width from the 2nd pulse to the Nth pulse does not change, which can reduce the brightness fluctuation of the pixel circuit 11 and improve the display effect.

[0174] In some embodiments, Figure 8As shown, the width of the first pulse of the start light emitting control signal STV-em is equal to the width of the pulse of the start light emitting control signal STV-em in the previous frame, so as to reduce the brightness flicker.

[0175] In some other embodiments, the width of the first pulse of the start light emitting control signal STV-em is not equal to the width of the pulse of the start light emitting control signal STV-em in the previous frame.

[0176] In some embodiments, the width of the first pulse of the start light emitting control signal STV-em is greater than the widths of the 2nd to Nth pulses.

[0177] For example, the width of the first pulse of the start light emitting control signal STV-em is 40H-200H, and the width of the second to Nth pulses is 20H-40H.

[0178] By setting the width of the first pulse of the start light emitting control signal STV-em to be greater than 40H, other stages before the light emitting stage t3 can be driven smoothly, and the complete function of the pixel circuit 11 can be better realized.

[0179] In some embodiments, the display driver 20 further includes a start anode reset control signal generating circuit.

[0180] The starting anode reset control signal generating circuit is used to generate a starting anode reset control signal STV-s1. The starting anode reset control signal STV-s1 is transmitted to the first control signal generating circuit 13 in the display screen 10. The first control signal generating circuit 13 outputs the first control signal s1 (that is, the anode reset control signal) to the first control signal terminal S1 of the plurality of pixel circuits 11 row by row.

[0181] Figure 9A-9C A brightness variation diagram corresponding to the timing of a starting anode reset control signal STV-s1 provided in an embodiment of the present application.

[0182] In some embodiments, the frequency of the start anode reset control signal STV-s1 is a fourth frequency f4, and the fourth frequency f4 is a common multiple of the screen refresh frequency supported by the terminal 1.

[0183] For example, Fig. 9A As shown, the fourth frequency f4 of the start anode reset control signal STV-s1 is 120 Hz. The screen refresh frequencies supported by the terminal 1 may include 10 Hz, 20 Hz, 30 Hz, 60 Hz, and 120 Hz. Fig. 9A The corresponding diagram of luminous brightness under various screen refresh frequencies is shown in the figure.

[0184] Or, illustratively, the fourth frequency f4 of the starting anode reset control signal STV-s1 is greater than or equal to 240 Hz.

[0185] For example, Fig. 9B As shown, the fourth frequency f4 of the start anode reset control signal STV-s1 is 240 Hz. The screen refresh frequencies supported by the terminal 1 may include 10 Hz, 20 Hz, 30 Hz, 60 Hz, 80 Hz, and 120 Hz. Fig. 9B The corresponding diagram of luminous brightness under various screen refresh frequencies is shown in the figure.

[0186] Or, for example, Fig. 9C As shown, the fourth frequency f4 of the start anode reset control signal STV-s1 is 360 Hz. The screen refresh frequencies supported by the terminal 1 may include 10 Hz, 20 Hz, 30 Hz, 60 Hz, 90 Hz, and 120 Hz. Fig. 9C The corresponding diagram of luminous brightness under various screen refresh frequencies is shown in the figure.

[0187] When the display driver 20 provided in the embodiment of the present application is applied to a terminal 1 with a high screen refresh rate, the terminal 1 can have a better fingerprint collection effect, and is suitable for the current mainstream terminals 1.

[0188] In some embodiments, Figure 1A As shown, the display driver 20 is also used to provide a starting second control signal STV-s2, which is transmitted to the second control signal generating circuit 14 in the display screen 10, and the second control signal generating circuit 14 outputs the second control signal s2 to the second control signal terminal S2 of multiple pixel circuits 11 row by row.

[0189] The display driver 20 is also used to provide a starting third control signal STV-s3, which is transmitted to the third control signal generating circuit 15 in the display screen 10. The third control signal generating circuit 15 outputs the third control signal s3 to the third control signal terminal S3 of the plurality of pixel circuits 11 row by row.

[0190] The display driver 20 is also used to provide a starting fourth control signal STV-s4, which is transmitted to the fourth control signal generating circuit 16 in the display screen 10. The fourth control signal generating circuit 16 outputs the fourth control signal s4 to the fourth control signal terminal S4 of the plurality of pixel circuits 11 row by row.

[0191] Based on the above display driver 20, reference Figure 1A The embodiment of the present application further provides a display screen 10, and the display screen 10 is coupled to any one of the above-mentioned display drivers 20.

[0192] The display screen 10 includes an em generating circuit 12 , a first control signal generating circuit 13 , a second control signal generating circuit 14 , a third control signal generating circuit 15 , a fourth control signal generating circuit 16 and a plurality of pixel circuits 11 .

[0193] The first control signal generating circuit 13 is coupled to the display driver 20 and the first control signal terminal S1 of the pixel circuit 11. The first control signal generating circuit 13 is used to receive the above-mentioned initial anode reset control signal STV-s1 output by the display driver 20 in the anode reset phase t, and output the first control signal s1 to the first control signal terminal S1 according to the initial anode reset control signal STV-s1. The timing of the first control signal s1 is the same as the timing of the initial anode reset control signal STV-s1.

[0194] The second control signal generating circuit 14 is coupled to the display driver 20 and the second control signal terminal S2 of the pixel circuit 11. The second control signal generating circuit 14 is used to receive the initial second control signal STV-s2 output by the display driver 20 in the initialization phase t1, and output the second control signal s2 to the second control signal terminal S2 according to the initial second control signal STV-s2. The timing of the second control signal s2 is the same as the timing of the initial second control signal STV-s2.

[0195] The third control signal generating circuit 15 is coupled to the display driver 20 and the third control signal terminal S3 of the pixel circuit 11. The third control signal generating circuit 15 is used to receive the initial third control signal STV-s3 output by the display driver 20 in the initialization phase t1, and output the third control signal s3 to the third control signal terminal S3 according to the initial third control signal STV-s3. The timing of the third control signal s3 is the same as the timing of the initial third control signal STV-s3.

[0196] The fourth control signal generating circuit 16 is coupled to the display driver 20 and the fourth control signal terminal S4 of the pixel circuit 11. The fourth control signal generating circuit 16 is used to receive the starting fourth control signal STV-s4 output by the display driver 20 in the threshold compensation phase t2, and output the fourth control signal s4 to the fourth control signal terminal S4 according to the starting fourth control signal STV-s4. The timing of the fourth control signal s4 is the same as the timing of the starting fourth control signal STV-s4.

[0197] The em generating circuit 12 is coupled to the display driver 20 and the light emitting control signal terminal EM of the pixel circuit 11. The em generating circuit 12 is used to receive the above-mentioned start light emitting control signal STV-em output by the display driver 20 in the light emitting stage t3, and output the light emitting control signal em to the light emitting control signal terminal EM according to the start light emitting control signal STV-em. The timing of the light emitting control signal em is the same as the timing of the start light emitting control signal STV-em.

[0198] The pixel circuit 11 in the display screen 10 provided in the embodiment of the present application at least includes a light-emitting control circuit 115 and a light-emitting unit 116. The light-emitting control circuit 115 is used to receive the above-mentioned light-emitting control signal em, and output a driving current to the light-emitting unit 116 under the control of the light-emitting control signal em, so as to drive the light-emitting unit 116 to emit light.

[0199] It can be understood that when the terminal 1 enters the local light spot control mode, the display driver 20 sends a start light control signal STV-em with a frequency of the first frequency f1 in the local light spot control mode. During the driving process of the display screen 10, after entering the light-emitting stage t3, it switches to the local light spot control mode, and the em generation circuit 12 outputs the light-emitting control signal em, and adjusts the frequency of the light-emitting control signal em to the first frequency f1. In an image frame, after the display screen 10 enters the light-emitting stage t3, in the local light spot control mode, the em generation circuit 12 outputs the light-emitting control signal em, and the pixel circuit 11 receives the light-emitting control signal em with a frequency adjusted to the first frequency f1, and drives the light-emitting unit 116 to emit light.

[0200] When the terminal 1 enters the first brightness mode, the display driver 20 sends a start light control signal STV-em with a frequency of the second frequency f2 in the first brightness mode. During the driving process of the display screen 10, after entering the light-emitting stage t3, it switches to the first brightness mode, and the em generation circuit 12 outputs the light-emitting control signal em, and adjusts the frequency of the light-emitting control signal em to the second frequency f2. Within an image frame, after entering the light-emitting stage t3, the display screen 10 also switches to the first brightness mode, and the em generation circuit 12 outputs the light-emitting control signal em. The pixel circuit 11 receives the light-emitting control signal em with a frequency adjusted to the second frequency f2, and drives the light-emitting unit 116 to emit light.

[0201] When the terminal 1 enters the second brightness mode, the display driver 20 sends a start light control signal STV-em with a frequency of the third frequency f3 in the second brightness mode. During the driving process of the display screen 10, after entering the light-emitting stage t3, it switches to the second brightness mode, and the em generation circuit 12 outputs the light-emitting control signal em, and adjusts the frequency of the light-emitting control signal em to the third frequency f3. Within an image frame, after entering the light-emitting stage t3, the display screen 10 also switches to the second brightness mode, and the em generation circuit 12 outputs the light-emitting control signal em. The pixel circuit 11 receives the light-emitting control signal em with a frequency adjusted to the third frequency f3, and drives the light-emitting unit 116 to emit light.

[0202] The frequency of the light emitting control signal em received by the light emitting control signal terminal EM of the pixel circuit 11 is switched synchronously with the frequency of the start light emitting control signal STV-em sent by the display driver 20 .

[0203] In some embodiments, the pixel circuit 11 also includes an anode reset circuit 111, which receives the above-mentioned anode reset control signal (for example, the above-mentioned first control signal s1), and under the control of the anode reset control signal, outputs an anode reset signal (for example, the first initialization voltage Vinit1 of the above-mentioned first initialization voltage terminal) to the anode of the light-emitting unit 116.

[0204] In one image frame, the display driver 20 sends out the above-mentioned starting anode reset control signal STV-s1. During the driving process of the display screen 10, after entering the anode reset stage t, the anode reset control signal generating circuit (first control signal generating circuit 13) generates an anode reset control signal (first control signal s1); the pixel circuit 11 is controlled by the anode reset signal with a frequency of the fourth frequency f4. In one image frame, after the display screen 10 enters the anode reset stage t, the anode reset control signal generating circuit generates an anode reset control signal; the pixel circuit 11 receives the anode reset signal with a frequency of the fourth frequency f4 to reset the anode of the light-emitting unit 116.

[0205] The pixel circuit 11 provided in the embodiment of the present application may also include other circuit modules. The embodiment of the present application does not limit the specific structure of the pixel circuit 11, nor does it limit the specific structure of the light emitting control circuit 115 and the anode reset circuit 111. Figure 2 The pixel circuit 11 shown in FIG. 1 is only a schematic diagram.

[0206] The embodiment of the present application further provides a display screen module, including the display screen 10 and the display driver 20 , wherein the display driver 20 is bonded to the display screen 10 .

[0207] The display screen module provided in the embodiment of the present application can be applied to the above-mentioned terminal 1 provided in the embodiment of the present application. The terminal 1 includes not only the display screen module but also a shell, and the display screen module is placed in the shell.

[0208] The embodiment of the present application further provides a display driver 20 , which includes a start light emission control signal STV-em generating circuit, which is used to send the start light emission control signal STV-em required for the display screen 10 to emit light to the display screen 10 .

[0209] The STV-em generating circuit receives the local spot control indication signal, switches to the local spot control mode, and adjusts the duty cycle of the start light control signal STV-em to be greater than the duty cycle of the start light control signal STV-em at the base frequency.

[0210] Correspondingly, the display screen 10 provided in the embodiment of the present application, during the driving process of the display screen 10, enters the light-emitting stage t3, switches to the local light spot control mode, and the em generation circuit 12 outputs the light-emitting control signal em, and adjusts the duty cycle of the light-emitting control signal em to be greater than the duty cycle of the light-emitting control signal em under the base frequency. The pixel circuit 11 enters the light-emitting stage t3 within an image frame, and in the local light spot control mode, the duty cycle of the received light-emitting control signal em is greater than the duty cycle of the light-emitting control signal em under the base frequency.

[0211] The display driver 20 provided in the embodiment of the present application, when the terminal 1 needs to perform fingerprint recognition, no matter which mode the previous frame is, the STV-em generation circuit will enter a specific local light spot control mode, and output a start light control signal STV-em that is unique to the local light spot control mode. That is, from normal full-screen light emission to local light spot light emission, the start light emission control signal STV-em no longer uses the duty cycle of the previous frame, but has an action to adjust the duty cycle, and adjusts the duty cycle of the start light emission control signal STV-em to be greater than the duty cycle of the start light emission control signal STV-em at the base frequency. Then, in the local light spot control mode, the pixel circuit 11 emits light under the drive of the light emission control signal em. By selecting the duty cycle as a suitable value, the light emission brightness of the pixel circuit 11 can be increased, and the horizontal stripe problem existing in fingerprint sampling can be significantly improved.

[0212] The display driver 20 and the display screen 10 provided in the embodiment of the present application can be applied to the terminal 1 provided in the embodiment of the present application.

[0213] The computer program corresponding to the display screen driving method provided in the embodiment of the present application may be stored in the hardware abstraction layer (HAL) of the terminal 1 , or may be stored in the kernel of the terminal 1 .

[0214] The embodiment of the present application also provides a computer readable medium storing a computer program. When the computer program is executed by a processor, the driving method of the pixel circuit described above is implemented. The embodiment of the present application provides a computer program product containing instructions. When the computer program product is run on a terminal, the terminal executes the driving method of the pixel circuit described above.

[0215] The computer readable medium may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory may exist independently and be connected to the processor via a communication bus. The memory may also be integrated with the processor.

[0216] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using a software program, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer execution instruction is loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instruction can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium.

[0217] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application shall be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A display driver, characterized in that: Applied to a terminal, the terminal comprising a display screen; The display driver comprises: A start light emission control signal generating circuit, used for sending a start light emission control signal required for emitting light to the display screen; The start light control signal generating circuit receives a local light spot control indication signal, switches to a local light spot control mode, and adjusts the frequency of the start light control signal to a first frequency, wherein the first frequency is M times the base frequency, and M is an integer greater than 1; the first frequency is a common multiple of the screen refresh frequency supported by the terminal; The local light spot control indication signal is used to indicate that the light brightness of a local area of ​​the display screen is greater than that of other areas.

2. The display driver according to claim 1, characterized in that: The start light emitting control signal generating circuit receives the first brightness indication signal, switches to the first brightness mode, and adjusts the frequency of the start light emitting control signal to the second frequency; The start light emitting control signal generating circuit receives the second brightness indication signal, switches to the second brightness mode, and adjusts the frequency of the start light emitting control signal to a third frequency; The second frequency is greater than the base frequency, and the third frequency is less than the second frequency; the second frequency and the third frequency are both common multiples of a screen refresh frequency supported by the terminal; The first brightness indication signal is used to instruct the display screen to emit light at a first brightness in full screen, and the second brightness indication signal is used to instruct the display screen to emit light at a second brightness in full screen.

3. The display driver according to claim 1 or 2, characterized in that: The base frequency is the maximum screen refresh frequency supported by the terminal.

4. The display driver according to any one of claims 1 to 3, characterized in that: The base frequency is 120 Hz.

5. The display driver according to any one of claims 1 to 4, characterized in that: In the local light spot control mode, within one image frame, the start light emission control signal includes N pulses, at least two of the N pulses have different widths; and N is an integer greater than 1.

6. The display driver according to claim 5, characterized in that: The widths of the 2nd to Nth pulses are equal.

7. The display driver according to claim 5 or 6, characterized in that: The width of the first pulse of the start light emitting control signal is equal to the width of the pulse of the start light emitting control signal in the previous frame.

8. The display driver according to any one of claims 5 to 7, characterized in that: The width of the first pulse of the start light emitting control signal is greater than 40H, where H is the duration of writing the data voltage to a pixel circuit of a row in the display screen.

9. The display driver according to any one of claims 1 to 8, characterized in that: The pulse width of the start light emitting control signal is in the range of 20H-200H, where H is the duration of writing the data voltage to a pixel circuit of a row in the display screen.

10. The display driver according to any one of claims 1 to 9, characterized in that: The display driver further comprises a start anode reset control signal generating circuit; The initial anode reset control signal generating circuit is used to generate an initial anode reset control signal, the frequency of the initial anode reset control signal is greater than or equal to 240 Hz and is a common multiple of the screen refresh frequency supported by the terminal.

11. A display screen, characterized in that: It includes a light emitting control signal generating circuit and a pixel circuit; The light emitting control signal generating circuit is used to receive the start light emitting control signal sent by the display driver and output the light emitting control signal; The pixel circuit comprises: a light emitting control circuit and a light emitting unit; The light emitting control circuit is used to receive the light emitting control signal, and output a driving current to the light emitting unit under the control of the light emitting control signal, so as to drive the light emitting unit to emit light; Wherein, in an image frame, entering the light-emitting stage, in the local light spot control mode, the frequency of the received light-emitting control signal is the light-emitting control signal adjusted to a first frequency, the first frequency is M times the base frequency, M is an integer greater than 1; the first frequency is a common multiple of the screen refresh frequency supported by the display screen; In the local light spot control mode, the local area of ​​the display screen emits light at a brightness greater than other areas.

12. The display screen according to claim 11, characterized in that: In an image frame, when entering the light-emitting stage and switching to the first brightness mode, the frequency of the received light-emitting control signal is the light-emitting control signal adjusted to the second frequency; In an image frame, when entering the light-emitting stage and switching to the second brightness mode, the frequency of the received light-emitting control signal is the light-emitting control signal adjusted to the third frequency; The second frequency is greater than the base frequency, and the third frequency is less than the second frequency; the second frequency and the third frequency are both common multiples of the screen refresh frequency supported by the display screen; Wherein, in the first brightness mode, the entire display screen emits light at a first brightness; in the second brightness mode, the entire display screen emits light at a second brightness.

13. The display screen according to claim 11 or 12, characterized in that: The base frequency is the maximum screen refresh frequency supported by the display screen.

14. The display screen according to any one of claims 11 to 13, characterized in that: In the local light spot control mode, within one image frame, the light control signal includes N pulses, at least two of the N pulses have different widths; and N is an integer greater than 1.

15. The display screen according to claim 14, characterized in that: The widths of the 2nd to Nth pulses are equal.

16. The display screen according to claim 14 or 15, characterized in that: The width of the first pulse of the light emitting control signal is equal to the width of the pulse of the light emitting control signal in the previous frame.

17. The display screen according to any one of claims 14 to 16, characterized in that: The width of the first pulse of the light emitting control signal is greater than 40H, where H is the duration of writing the data voltage to the pixel circuit.

18. The display screen according to any one of claims 11 to 17, characterized in that: The pulse width of the light emitting control signal is in the range of 20H-200H, where H is the duration of writing the data voltage to the pixel circuit.

19. The display screen according to any one of claims 11 to 18, characterized in that: The display screen further includes an anode reset control signal generating circuit; the pixel circuit further includes an anode reset circuit; The anode reset control signal generating circuit is used to generate an anode reset control signal; The anode reset circuit is used to receive the anode reset control signal, and output an anode reset signal to the anode of the light emitting unit under the control of the anode reset control signal; The frequency of the anode reset control signal is greater than or equal to 240 Hz and is a common multiple of the screen refresh frequency supported by the display screen.

20. A method for driving a display screen, characterized in that: The display screen includes a light emitting control signal generating circuit and a pixel circuit; The pixel circuit comprises: a light emitting control circuit and a light emitting unit; The driving method comprises: In an image frame, the light-emitting stage is entered and the local light spot control mode is switched. The light-emitting control signal generating circuit outputs a light-emitting control signal, and the frequency of the light-emitting control signal is adjusted to a first frequency, where the first frequency is M times the base frequency, and M is an integer greater than 1; the first frequency is a common multiple of the screen refresh frequency supported by the display screen; The light emitting control circuit outputs a driving current to the light emitting unit under the control of the light emitting control signal, so as to drive the light emitting unit to emit light; Wherein, in the local light spot control mode, the local area of ​​the display screen has a greater light brightness than other areas.

21. The driving method according to claim 20, characterized in that: The driving method further comprises: In one image frame, entering the light-emitting stage, switching to the first brightness mode, and adjusting the frequency of the light-emitting control signal to the second frequency; In one image frame, entering the light-emitting stage, switching to the second brightness mode, and adjusting the frequency of the light-emitting control signal to a third frequency; The second frequency is greater than the base frequency, and the third frequency is less than the second frequency; the second frequency and the third frequency are both common multiples of the screen refresh frequency supported by the display screen; Wherein, in the first brightness mode, the entire display screen emits light at a first brightness; in the second brightness mode, the entire display screen emits light at a second brightness.

22. The driving method according to claim 20 or 21, characterized in that: The base frequency is the maximum screen refresh frequency supported by the display screen.

23. The driving method according to any one of claims 20 to 22, characterized in that: The base frequency is 120 Hz.

24. The driving method according to any one of claims 20 to 23, characterized in that: In the local light spot control mode, within one image frame, the light control signal includes N pulses, at least two of the N pulses have different widths; and N is an integer greater than 1.

25. The driving method according to claim 24, characterized in that: The widths of the 2nd to Nth pulses are equal.

26. The driving method according to claim 24 or 25, characterized in that: The width of the first pulse of the light emitting control signal is equal to the width of the pulse of the light emitting control signal in the previous frame.

27. The driving method according to any one of claims 24 to 26, characterized in that: The width of the first pulse of the light emitting control signal is greater than 40H, where H is the duration of writing the data voltage to the pixel circuit.

28. The driving method according to any one of claims 20 to 27, characterized in that: The pulse width of the light emitting control signal is in the range of 20H-200H, where H is the duration of writing the data voltage to the pixel circuit.

29. The driving method according to any one of claims 20 to 28, characterized in that: The display screen further includes an anode reset control signal generating circuit; the pixel circuit further includes an anode reset circuit; The driving method further comprises: In an image frame, before the light emitting stage, an anode reset stage is entered, and the anode reset control signal generating circuit generates an anode reset control signal; the anode reset circuit outputs an anode reset signal to the anode of the light emitting unit under the control of the anode reset control signal; The frequency of the anode reset control signal is greater than or equal to 240 Hz and is a common multiple of the screen refresh frequency supported by the display screen.

30. A display driver, characterized in that: Applied to a terminal, the terminal includes a display screen; the display driver includes: A start light emission control signal generating circuit, used for sending a start light emission control signal required for emitting light to the display screen; The start light control signal generating circuit receives a local light spot control indication signal, switches to a local light spot control mode, and adjusts the duty cycle of the start light control signal to be greater than the duty cycle of the start light control signal at the base frequency; The local light spot control indication signal is used to indicate that the light brightness of a local area of ​​the display screen is greater than that of other areas.

31. A display screen, characterized in that: It includes a light emitting control signal generating circuit and a pixel circuit; The light emitting control signal generating circuit is used to receive the start light emitting control signal sent by the display driver and output the light emitting control signal; The pixel circuit comprises: a light emitting control circuit and a light emitting unit; The light emitting control circuit is used to receive the light emitting control signal, and output a driving current to the light emitting unit under the control of the light emitting control signal, so as to drive the light emitting unit to emit light; Wherein, in an image frame, entering the light-emitting stage, in the local light spot control mode, the duty cycle of the received light-emitting control signal is greater than the duty cycle of the light-emitting control signal under the base frequency; In the local light spot control mode, the local area of ​​the display screen emits light at a brightness greater than other areas.

32. A method for driving a display screen, characterized in that: The display screen includes a light emitting control signal generating circuit and a pixel circuit; The pixel circuit comprises: a light emitting control circuit and a light emitting unit; The driving method comprises: In one image frame, the light-emitting stage is entered, and the local light spot control mode is switched, and the light-emitting control signal generating circuit outputs the light-emitting control signal, and the duty cycle of the light-emitting control signal is adjusted to be greater than the duty cycle of the light-emitting control signal under the base frequency; The light emitting control circuit outputs a driving current to the light emitting unit under the control of the light emitting control signal, so as to drive the light emitting unit to emit light; Wherein, in the local light spot control mode, the local area of ​​the display screen has a greater light brightness than other areas.

33. A display screen module, characterized in that: Including display driver and display screen; The display driver includes the display driver described in any one of claims 1-10 or 30, and / or the display screen includes the display screen described in any one of claims 11-19 or 31; the display screen is used to receive the start light emission control signal sent by the display driver.

34. A terminal, characterized in that: It comprises a shell and a display screen module, wherein the display screen module is arranged in the shell; the display screen module comprises the display screen module described in claim 33.

35. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program runs on the terminal, the terminal executes the driving method according to any one of claims 20 to 29 or 32.

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