LIQUID CRYSTAL DRIVING APPARATUS AND METHOD FOR DRIVING LIQUID CRYSTAL

Abstract

 Embodiments of this application provide a liquid crystal drive apparatus and a method for driving a liquid crystal. The liquid crystal drive apparatus includes: a processor, configured to send a first drive control signal to a liquid crystal driver; and the liquid crystal driver, configured to convert the first drive control signal into a plurality of groups of first voltage signals. Each of the plurality of groups of first voltage signals includes a plurality of first voltages, and the plurality of first voltages are in a one-to-one correspondence with a plurality of pixels in a liquid crystal display; and output the plurality of groups of first voltage signals to a plurality of electrodes of the plurality of pixels in a time division manner within a first preset time period, to control grayscales of the plurality of pixels. Each group of first voltage signals is output in a period of time within the first preset time period, each of the plurality of first voltages is used to control a grayscale of a pixel corresponding to the first voltage, and at least two of the plurality of groups of first voltage signals are different, to implement a finer grayscale adjustment of the liquid crystal display.

Description

TECHNICAL FIELD

[0001] Embodiments of this application relate to the field of display technologies, and in particular, to a liquid crystal drive apparatus and a method for driving a liquid crystal.

BACKGROUND

[0002] With progress of electronic science and technology, performance of electronic devices is improved rapidly. An increasing quantity of users prefer to use electronic devices to shoot an image, watch a video, and the like. This imposes a higher requirement on image quality of a liquid crystal display. High dynamic range (high dynamic range, HDR) display technology is widely used to improve the image quality.

[0003] Currently, in an HDR display technology applied to the liquid crystal display, a plurality of frames of images with different brightness are usually generated within one time period, and the plurality of frames of images with different brightness are superimposed to generate a new image. However, this method is prone to image flickering. Therefore, the industry further proposes modifying a hardware structure of a liquid crystal driver circuit (for example, adding more stages of voltage divider resistors to a digital-to-analog conversion circuit), to implement a grayscale adjustment with finer accuracy. However, modifying the hardware structure of the liquid crystal driver circuit causes an excessively large layout area occupied by a chip and an increase in manufacturing costs of a liquid crystal driver module. In addition, it is usually difficult to adapt the modified hardware structure to another existing module (such as a communication module or a processing module) in the electronic device. Consequently, it is difficult to implement a solution of modifying the hardware structure of the liquid crystal driver circuit. In conclusion, improving image display effect of the liquid crystal display still becomes a problem that needs to be resolved.

SUMMARY

[0004] This application provides a liquid crystal drive apparatus and a method for driving a liquid crystal, to implement a finer grayscale adjustment of a liquid crystal display. This improves image display effect of the liquid crystal display. To achieve the foregoing objectives, the following technical solutions are used in this application.

[0005] According to a first aspect, an embodiment of this application provides a liquid crystal drive apparatus. The liquid crystal drive apparatus includes a processor and a liquid crystal driver. The processor is configured to send a first drive control signal to the liquid crystal driver. The liquid crystal driver is configured to convert the first drive control signal into a plurality of groups of first voltage signals, where each of the plurality of groups of first voltage signals includes a plurality of first voltages, and the plurality of first voltages are in a one-to-one correspondence with a plurality of pixels in a liquid crystal display; and output the plurality of groups of first voltage signals to a plurality of electrodes of the plurality of pixels in a time division manner within a first preset time period, to control grayscales of the plurality of pixels. Each group of first voltage signals is output in a period of time within the first preset time period, each of the plurality of first voltages is used to control a grayscale of a pixel corresponding to the first voltage, and at least two of the plurality of groups of first voltage signals are different.

[0006] Usually, due to inertia of liquid crystal molecules, voltages of different magnitudes are applied to pixel electrodes in the liquid crystal display within a time period. Impact of an electrostatic field generated by the voltages of different magnitudes on the liquid crystal molecules is the same as impact of an electrostatic field generated by effective values of the voltages in the time period on the liquid crystal molecules. The same impact may mean that deflection angles of the liquid crystal molecules are the same. Therefore, in the liquid crystal drive apparatus provided in this embodiment of this application, the processor sends a plurality of groups of drive control signals to the liquid crystal driver, so that the liquid crystal driver can convert the plurality of groups of drive control signals into a plurality of voltage values within a corresponding time period, so that effective values of the plurality of voltage values are preset voltage values. More voltage values can be further inserted based on an existing voltage, so that the liquid crystal molecules in the liquid crystal display can be controlled to implement more deflection angles. In this way, a finer grayscale adjustment of the liquid crystal display can be implemented, so that image quality of the liquid crystal display can be improved.

[0007] Based on the first aspect, in a possible implementation, the first preset time period is a display refresh period of the liquid crystal display.

[0008] The first preset period is set to the display refresh period of the liquid crystal display, so that the liquid crystal driver can supply variable voltages for the pixel electrodes in the liquid crystal display within the display refresh period of the liquid crystal display, and more voltage values can be further inserted based on the existing voltage. Compared with a conventional technology in which fixed voltages are provided for the pixel electrodes in the liquid crystal display within the display refresh period of the liquid crystal display, a finer grayscale adjustment of the liquid crystal display can be implemented, so that the image quality of the liquid crystal display can be improved.

[0009] Based on the first aspect, in a possible implementation, the first drive control signal includes a plurality of groups of first drive control signals, the liquid crystal driver includes a digital-to-analog conversion circuit, and the digital-to-analog conversion circuit is configured to convert each of the plurality of groups of first drive control signals into one group of voltage signals.

[0010] Based on the first aspect, in a possible implementation, the liquid crystal driver further includes a memory, and the processor is specifically configured to: store the plurality of groups of first drive control signals into the memory after the liquid crystal drive apparatus is powered on, when the liquid crystal display is lit up, during a video play process, or when a display image is switched.

[0011] Based on the first aspect, in a possible implementation, the liquid crystal driver further includes a time sequence controller, where the time sequence controller is configured to generate a clock signal, and the first preset time period includes a plurality of clock periods of the clock signal; and the liquid crystal driver is specifically configured to: based on the clock signal, read the plurality of groups of first drive control signals from the memory in the time division manner; and convert the plurality of groups of first drive control signals into the plurality of groups of first voltage signals.

[0012] Based on the first aspect, in a possible implementation, the at least two groups of first voltage signals include a first group of first voltage signals and a second group of first voltage signals; and a first voltage for a pixel in the first group of first voltage signals is different from a first voltage for the pixel in the second group of first voltage signals.

[0013] Based on the first aspect, in a possible implementation, a first voltage for a pixel in any one of the at least two groups of first voltage signals is different from a first voltage for the pixel in any other one of the at least two groups of first voltage signals.

[0014] Based on the first aspect, in a possible implementation, within the first preset time period, the plurality of first voltages are positive voltage signals. The processor is further configured to send a second drive control signal to the liquid crystal driver. The liquid crystal driver is further configured to: convert the second drive control signal into a plurality of groups of second voltage signals, where each of the plurality of groups of second voltage signals includes a plurality of second voltages, and the plurality of second voltages are in a one-to-one correspondence with the plurality of pixels; and output the plurality of groups of second voltage signals to the plurality of electrodes in the time division manner within a second preset time period. Each group of second voltage signals is output in a period of time within the second preset time period, each of the plurality of second voltages is used to control a grayscale of a pixel corresponding to the second voltage, and at least two of the plurality of groups of second voltage signals are different. Within the second preset time period, the plurality of second voltages are negative voltage signals.

[0015] Based on the first aspect, in a possible implementation, the second preset time period is the display refresh period of the liquid crystal display.

[0016] Within the first preset time period, the plurality of first voltages are set to positive voltage signals, and within the second preset time period, the plurality of second voltages are set to negative voltage signals. This can avoid liquid crystal aging, and consequently improve a service life of a liquid crystal.

[0017] Based on the first aspect, in a possible implementation, the at least two groups of second voltage signals include a first group of second voltage signals and a second group of second voltage signals; and a second voltage for a pixel in the first group of second voltage signals is different from a second voltage for the pixel in the second group of second voltage signals.

[0018] Based on the first aspect, in a possible implementation, a second voltage for a pixel in any one of the at least two groups of second voltage signals is different from a first voltage for the pixel in any other one group of first voltage signals of the at least two groups of second voltage signals.

[0019] Based on the first aspect, in a possible implementation, the liquid crystal drive apparatus further includes the liquid crystal display.

[0020] According to a second aspect, an embodiment of this application provides a method for driving a liquid crystal. The method includes: A processor in a liquid crystal drive apparatus sends a first drive control signal to a liquid crystal driver. The liquid crystal driver in the liquid crystal drive apparatus converts the first drive control signal into a plurality of groups of first voltage signals, where each of the plurality of groups of first voltage signals includes a plurality of first voltages, and the plurality of first voltages are in a one-to-one correspondence with a plurality of pixels in a liquid crystal display; and outputs the plurality of groups of first voltage signals to a plurality of electrodes of the plurality of pixels in a time division manner within a first preset time period, to control grayscales of the plurality of pixels. Each group of first voltage signals is output in a period of time within the first preset time period, each of the plurality of first voltages is used to control a grayscale of a pixel corresponding to the first voltage, and at least two of the plurality of groups of first voltage signals are different.

[0021] Based on the second aspect, in a possible implementation, the at least two groups of first voltage signals include a first group of first voltage signals and a second group of first voltage signals; and a first voltage for a pixel in the first group of first voltage signals is different from a first voltage for the pixel in the second group of first voltage signals.

[0022] Based on the second aspect, in a possible implementation, a first voltage for a pixel in any one of the at least two groups of first voltage signals is different from a first voltage for the pixel in any other one of the at least two groups of first voltage signals.

[0023] Based on the second aspect, in a possible implementation, the first preset time period is a display refresh period of the liquid crystal display.

[0024] Based on the second aspect, in a possible implementation, the first drive control signal includes a plurality of groups of first drive control signals; and that the liquid crystal driver in the liquid crystal drive apparatus converts the first drive control signal into a plurality of groups of first voltage signals includes: The liquid crystal driver converts each of the plurality of groups of first drive control signals into one group of first voltage signals.

[0025] Based on the second aspect, in a possible implementation, that a processor in a liquid crystal drive apparatus sends a first drive control signal to a liquid crystal driver includes: storing the plurality of groups of first drive control signals into a memory of the liquid crystal driver after the liquid crystal drive apparatus is powered on, when the liquid crystal display is lit up, during a video play process, or when a display image is switched.

[0026] Based on the second aspect, in a possible implementation, that the liquid crystal driver in the liquid crystal drive apparatus converts the first drive control signal into a plurality of groups of first voltage signals includes: Based on a clock signal generated by a time sequence controller in the liquid crystal driver, the liquid crystal driver reads the plurality of groups of first drive control signals from the memory in a time division manner within the first preset time period, and converts the plurality of groups of first drive control signals into the plurality of groups of first voltage signals, where the first preset time period includes a plurality of clock periods of the clock signal.

[0027] Based on the second aspect, in a possible implementation, within the first preset time period, the plurality of first voltages are positive voltage signals; and the method further includes: The processor sends a second drive control signal to the liquid crystal driver. The liquid crystal driver converts the second drive control signal into a plurality of groups of second voltage signals, where each of the plurality of groups of second voltage signals includes a plurality of second voltages, and the plurality of second voltages are in a one-to-one correspondence with the plurality of pixels; and outputs the plurality of groups of second voltage signals to the plurality of electrodes in a time division manner in a second preset time period. Each group of second voltage signals is output in a period of time within the second preset time period, each of the plurality of second voltages is used to control a grayscale of a pixel corresponding to the second voltage, and at least two of the plurality of groups of second voltage signals are different. Within the second preset time period, the plurality of second voltages are negative voltage signals.

[0028] Based on the second aspect, in a possible implementation, the second preset time period is the display refresh period of the liquid crystal display.

[0029] Based on the second aspect, in a possible implementation, the at least two groups of second voltage signals include a first group of second voltage signals and a second group of second voltage signals; and a second voltage for a pixel in the first group of second voltage signals is different from a second voltage for the pixel in the second group of second voltage signals.

[0030] Based on the second aspect, in a possible implementation, a second voltage for a pixel in any one of the at least two groups of second voltage signals is different from a first voltage for the pixel in any other one group of first voltage signals of the at least two groups of second voltage signals.

[0031] It should be understood that technical solutions in the second aspect of this application are consistent with those in the first aspect of this application, and beneficial effects achieved by the aspects and the corresponding feasible implementations are similar. Details are not described again.

BRIEF DESCRIPTION OF DRAWINGS

[0032] To describe technical solutions in embodiments of this application more clearly, the following briefly describes the accompanying drawings for describing embodiments of this application. It is clear that the accompanying drawings in the following descriptions show merely some embodiments of this application, and a person of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.

FIG. 1 is a schematic diagram of an application scenario according to an embodiment of this application;

FIG. 2 is a schematic diagram of a voltage used to drive a liquid crystal to deflect according to an embodiment of this application;

FIG. 3 is a schematic diagram of a structure of a liquid crystal drive apparatus according to an embodiment of this application;

FIG. 4 is a schematic diagram of a structure of an electrode plate 20 according to an embodiment of this application;

FIG. 5 is a schematic diagram of a structure of a liquid crystal driver according to an embodiment of this application;

FIG. 6 is a schematic diagram of a structure of a digital-to-analog converter according to an embodiment of this application; and

FIG. 7 is a schematic diagram of a structure of a method for driving a liquid crystal according to an embodiment of this application.

DESCRIPTION OF EMBODIMENTS

[0033] The following clearly and completely describes the technical solutions in embodiments of this application with reference to the accompanying drawings in embodiments of this application. It is clear that the described embodiments are some but not all of embodiments of this application. All other embodiments obtained by a person of ordinary skill in the art based on embodiments of this application without creative efforts shall fall within the protection scope of this application.

[0034] Terms such as "first", "second", or the like mentioned in this specification do not indicate any order, quantity, or importance, but are used only for distinguishing between different components. Likewise, terms such as "a/an", "one", or the like do not indicate a quantity limitation, but mean at least one. Terms such as "coupled" or the like are not limited to a direct physical or mechanical connection, but may include an electrical connection, regardless of a direct or indirect connection, equivalent to a connection in a broad sense.

[0035] In embodiments of this application, words such as "example" or "for example" represent giving an example, an illustration, or a description. Any embodiment or design described by "example" or "for example" in embodiments of this application should not be construed as being more preferred or advantageous than another embodiment or design. To be precise, words such as "example" or "for example" are intended to present a related concept in a specific manner. In the description of embodiments of this application, unless otherwise specified, "a plurality of" means two or more. For example, a plurality of data signal output ends means two or more data signal output ends.

[0036] A liquid crystal drive apparatus provided in embodiments of this application may include an electronic device or a module, a chip, a chip set, a circuit board, or a component integrated in an electronic device. The electronic device may be user equipment (User Equipment, UE), for example, various types of portable devices such as a mobile phone, a tablet computer, or a wearable device (such as a smartwatch). The electronic device may be installed with a liquid crystal display 200 shown in FIG. 1, and a liquid crystal drive apparatus 100 may drive the liquid crystal display 200 to display an image. When the liquid crystal drive apparatus 100 is a chip or a chip set or a circuit board carrying a chip or a chip set, the chip or the chip set or the circuit board carrying a chip or a chip set may work under software driving. This embodiment of this application is described by using an example in which the liquid crystal drive apparatus 100 and the liquid crystal display 200 are separately disposed, but is not intended to limit the solution.

[0037] FIG. 1 is a schematic diagram of an application scenario of a liquid crystal drive apparatus 100 according to an embodiment of this application. In the application scenario shown in FIG. 1, the liquid crystal drive apparatus 100 and a liquid crystal display 200 are shown. First, a structure and a display principle of the liquid crystal display 200 are described. The liquid crystal display 200 usually includes a plurality of components, for example, an electrode plate 20, an electrode plate 21, a liquid crystal layer 23, a backlight panel 24, a polarizer 25, a color filter 26, and a polarizer 27 shown in FIG. 1. The liquid crystal display 200 may further include more components. Details are not described again. The liquid crystal layer 23 is disposed between the electrode plate 20 and the electrode plate 21. After the liquid crystal display 200 is powered on, light is emitted from a side of the backlight panel 24, and passes through the polarizer 25, the electrode plate 20, the liquid crystal layer 23, the electrode plate 21, the color filter 26, and the polarizer 27, to present an image on the screen. The liquid crystal drive apparatus 100 is connected to the electrode plate 20 and the electrode plate 21. After the liquid crystal drive apparatus 100 is powered on, the liquid crystal drive apparatus 100 applies a voltage to the electrode plate 20 and the electrode plate 21 (for example, applies a positive and negative alternating voltage to the electrode plate 20, and applies a common voltage to the electrode plate 21). Therefore, an electrostatic field is formed between the electrode plate 20 and the electrode plate 21. Liquid crystal molecules in the liquid crystal layer 23 deflect under an action of the electrostatic field, that is, an arrangement direction of the liquid crystal molecules changes. Different magnitudes of voltages applied lead to different deflection angles of the liquid crystal molecules, and different arrangement directions of the liquid crystal molecules. Because light has a characteristic of propagating in a crystal extension direction of the liquid crystal molecules, the arrangement direction of the liquid crystal molecules may be controlled by controlling a magnitude of the voltage applied to the electrode plate 20, to control a grayscale of the liquid crystal display 200.

[0038] Based on the foregoing display principle of the liquid crystal display 200, higher accuracy of the voltage applied to the electrode plate 20 and the electrode plate 21 indicates a larger quantity of digits of a grayscale value and higher image quality of the liquid crystal display. In a conventional technology, voltage accuracy is implemented by using a plurality of voltage divider resistors disposed in a liquid crystal drive apparatus. A larger quantity of voltage divider resistors indicates finer voltage division. Certainly, a larger quantity of voltage divider resistors indicates a larger quantity of signal transmission lines that are led out from the voltage divider resistors. However, excessive signal transmission lines cause a larger parasitic capacitance to be generated in a signal transmission line area, and an excessively large parasitic capacitance severely reduces a signal transmission rate. Consequently, display effect of the liquid crystal display 200 is affected. Therefore, in the liquid crystal display technology, it is difficult to further improve the image quality of the liquid crystal display by disposing more voltage divider resistors to implement refined voltage division.

[0039] Based on the foregoing display principle of the liquid crystal display 200, further, due to inertia of the liquid crystal molecules, the voltages of different magnitudes are applied to the electrode plate 20 and the electrode plate 21 in a specific time. Impact of an electrostatic field generated by the voltages of different magnitudes on the liquid crystal molecules is the same as impact of an electrostatic field generated by effective values of the voltages in the specific time on the liquid crystal molecules. The same impact may mean that deflection angles of the liquid crystal molecules are the same. Using FIG. 2 as an example, the following describes the principle in more detail. (a) in FIG. 2 shows a case of a voltage applied to the liquid crystal molecules within each period when the liquid crystal display 200 displays a same frame of image. (b) in FIG. 2 shows an effective voltage value of the voltage in each period in (a) in FIG. 2. As shown in (a) in FIG. 2, a period T1 is divided into four identical time periods t1 to t4, and a period T2 is divided into four identical time periods t5 to t8, where the period T1 and the period T2 can separately be a period of one refresh of the liquid crystal display (for example, a time when the liquid crystal molecules rotate in response to the electrostatic field). Within the period T1, a forward ("+") voltage is applied to the liquid crystal molecules. Within the period T2, a negative ("-") voltage is applied to the liquid crystal molecules. It should be noted that a forward direction and a negative direction of the voltage in embodiments of this application only represent voltage polarities, and are not used to limit a magnitude of the voltage. As shown in (a) in FIG. 2, a 2 V voltage is applied to the electrode plate 20 and the electrode plate 21 in the time period 11, a 4 V voltage is applied to the electrode plate 20 and the electrode plate 21 in the time period t2, a 3 V voltage is applied to the electrode plate 20 and the electrode plate 21 in the time period t3, and a 2 V voltage is applied to the electrode plate 20 and the electrode plate 21 in the time period t4. An effective value of the voltage applied to the electrode plate 20 and the electrode plate 21 within the period T1 is [(2² + 4² + 3² + 2²)/4]^½ = 2. 87V, as shown in (b) in FIG. 2. Consequently, electrostatic fields generated by the voltages in the four time periods t1 to t4 have the same impact on a liquid crystal as an electrostatic field generated by the 2.87 V voltage does. Similarly, a -2 V voltage is applied to the electrode plate 20 and the electrode plate 21 in the time period t5, a -4 V voltage is applied to the electrode plate 20 and the electrode plate 21 in the time period t6, a -3 V voltage is applied to the electrode plate 20 and the electrode plate 21 in the time period t3, and a -2 V voltage is applied to the electrode plate 20 and the electrode plate 21 in the time period t2. An effective value of the negative voltage applied to the electrode plate 20 and the electrode plate 21 within the period T2 is -2. 87 V, as shown in (b) in FIG. 2. Consequently, electrostatic fields generated by the voltages in the four time periods t5 to t8 have the same impact on the liquid crystal as an electrostatic field generated by the 2.87 V voltage does. Consequently, a voltage Vrms of an electrostatic field applied to the liquid crystal molecules within one period T may be represented by the following formula (1). V1 is the voltage in the time period t1, and Vn is a voltage of a time period tn. It is assumed that time periods t1 to tn are all identical time periods.

[0040] It can be learned from the foregoing working principle of the liquid crystal display 200 and the foregoing formula (1) that, in the liquid crystal drive apparatus provided in this embodiment of this application, different voltages are applied to the electrode plate 20 and the electrode plate 21 within a time period, so that an effective value of a voltage in the time period is a preset voltage value, and more voltage values can be further set based on voltages divided by a voltage divider resistor, to control the liquid crystal molecules in the liquid crystal display 200 to implement more deflection angles. In this way, a finer grayscale adjustment of the liquid crystal display 200 can be implemented, so that image quality of the liquid crystal display 200 can be improved. The following describes, in more detail by using embodiments shown in FIG. 3 to FIG. 7, the liquid crystal drive apparatus 100 provided in embodiments of this application.

[0041] FIG. 3 is a schematic diagram of a structure of a liquid crystal drive apparatus 100 according to an embodiment of this application. A specific product form of the liquid crystal drive apparatus 100 is described above. Details are not described again. The liquid crystal drive apparatus 100 includes a liquid crystal driver 10 and one or more processors. For example, the one or more processors include a processor 11 shown in FIG. 3. The processor 11 may be a central processing unit (CPU, central processing unit), or may alternatively be a microcontroller (MCU, microcontroller unit). Optionally, the one or more processors may be integrated in one or more chips, and the one or more chips may be considered as one chip set. In a specific example, the processor 11 may be integrated in a system on chip (SOC, System on Chip). An apparatus or component such as a cache may also be integrated in the SOC. The liquid crystal driver 10 may be disposed outside the SOC. In addition, the electronic apparatus 100 includes one or more other necessary components, such as a storage device 12 and a power management integrated circuit (power management integrated circuit, PMIC) 13. Software programs or software plugins such as operating system software and application software may be run in the processor 11. The storage device 12 may store a software program or software plugin required for operation of the processor 11. The power management integrated circuit 13 is used to obtain electric energy from a power supply (for example, a battery or a household power grid), and output the electric energy to the processor 11 and the liquid crystal driver 10, to supply power to the processor 11 and the liquid crystal driver 10. The processor 11 may send a drive control signal to the liquid crystal driver 10 after power-on, when the liquid crystal display 200 is lit up, during a video play process, or when a display image is switched. The liquid crystal driver 10 converts the drive control signal into a plurality of groups of voltage signals, and transmits a plurality of voltages of different voltage values to an electrode plate 20 on the liquid crystal display 200 within a time period T. The time period T is a display refresh period of the liquid crystal display 200.

[0042] In this embodiment of this application, by row scanning or column scanning, the liquid crystal driver 10 may light up the liquid crystal display 200 row by row or column by column. Row scanning is used as an example for description in this embodiment of this application. Usually, pixel electrodes arranged in an array are disposed on the electrode plate 20 on the liquid crystal display 200. FIG. 4 is a schematic diagram of a structure of an electrode plate 20 according to an embodiment of this application. The liquid crystal driver 10 includes a plurality of data signal output ends. The plurality of data signal output ends are respectively correspondingly coupled to a plurality of rows of pixel electrodes shown in FIG. 4. That is, one of the plurality of data signal output ends is coupled to one of the plurality of rows of pixel electrodes. A quantity of data signal output ends in the liquid crystal driver 10 is the same as a quantity of pixel electrodes in each row on the electrode plate 20. FIG. 3 shows an example of the liquid crystal driver 10 including 320 data signal output ends s1 to s320. FIG. 4 shows an example of each row of the electrode plate 20 including 320 pixel electrodes p1 to p320. It should be noted that the quantity of data signal output ends included in the liquid crystal driver 10 is not specifically limited in this embodiment of this application. The quantity of data signal output ends included in the liquid crystal driver 10 is determined based on a quantity of pixel electrodes in each row of a liquid crystal display. In addition, the liquid crystal driver 10 also includes a plurality of scan signal output ends (not shown in the figure) for selecting a specific row of pixels. A quantity of scan signal output ends may be the same as the quantity of pixel electrodes in each row of the liquid crystal display. The data signal output ends s1 to s320 in the liquid crystal driver 10 are respectively connected to the pixel electrodes on the electrode plate 20 through corresponding data signal lines. The liquid crystal driver 10 supplies voltages to each row of pixel electrodes through the data signal output ends s1 to s320 based on the drive control signal transmitted by the processor 11, to control liquid crystal molecules to deflect, thereby displaying different grayscales. Different voltages are applied to the pixel electrodes, and the liquid crystal display presents different grayscales. Specifically, the liquid crystal driver 10 converts the drive control signal into the plurality of groups of voltage signals. At least two of the plurality of groups of voltage signals are different. Each of the plurality of groups of voltage signals includes a plurality of voltages. The plurality of voltages are in a one-to-one correspondence with pixels in the liquid crystal display 200. In addition, the liquid crystal driver 10 is further configured to output the plurality of groups of voltage signals to pixel electrodes 20 in a time division manner within the time period T, to control a grayscale of a pixel corresponding to each pixel electrode 20. The time period T is a display refresh period of the liquid crystal display. Each group of voltage signals is output within a period of time of the time period T. For a plurality of voltages in each group of voltage signals, each of the plurality of voltages is respectively used to control a grayscale of a pixel corresponding to the voltage. For example, the liquid crystal driver 10 converts the drive signal sent by the processor 11 into three groups of voltage signals: a group of voltage signals N1, a group of voltage signals N2 and a group of voltage signals N3. Further, each group of voltage signals may further include 320 times 240 = 76,800 (it is assumed that each row of the electrode plate 20 shown in FIG. 4 includes 320 pixel electrodes, and each column includes 240 pixel electrodes) voltages. Consequently, 76,800 voltages included in the voltage signals N1 may be separately supplied to each pixel electrode on the electrode plate 20 shown in FIG. 4 within a time period t1 of the time period T. 76,800 voltages included in the voltage signals N2 may be separately provided to each pixel electrode on the electrode plate 20 shown in FIG. 4 within a time period t2 of the time period T. 76,800 voltages included in the voltage signals N3 may be separately provided to each pixel electrode on the electrode plate 20 shown in FIG. 4 within a time period t3 of the time period T. In this way, the group of voltage signals N1, the group of voltage signals N2, and the group of voltage signals N3 separately apply voltages to each pixel electrode within different time periods of the time period T, to control a grayscale of a pixel corresponding to each pixel electrode. In a possible implementation, a voltage for a pixel A in the voltage signals N1 may be the same as a voltage for the pixel A in the voltage signals N2. The voltage for the pixel A in the voltage signals N1 may be different from a voltage for the pixel A in the voltage signals N3. In another possible implementation, a voltage for a pixel A in the voltage signals N1, a voltage for the pixel A in the voltage signals N2 and a voltage for the pixel A in the voltage signals N3 differ in pairs. It should be noted that in this embodiment of this application, a quantity of voltages applied to each pixel electrode and a quantity of gray levels presented on the liquid crystal display are determined by a quantity of digits of the drive control signal output by the processor 11 and a quantity of different voltage values within the time period T.

[0043] Based on a user's trigger, the processor 11 may send a plurality of groups of drive control signals to the liquid crystal driver 10 in a plurality of scenarios such as after power-on, when the liquid crystal display 200 is lit up, during the video play process, or when the display image is switched. For example, the processor 11 may send the plurality of groups of drive control signals to the liquid crystal driver 10 when the user triggers the liquid crystal display 200 to light up, and may send the plurality of groups of drive control signals to the liquid crystal driver 10 again when the processor 11 receives an instruction to switch the display image. For another example, the processor 11 may send the plurality of groups of drive control signals to the liquid crystal driver 10 based on a preset frame rate during a video play process by the user. For example, a frame rate is 1/60s, and the processor 11 sends the plurality of groups of drive control signals to the liquid crystal driver 10 at an interval of 1/60s. The plurality of groups of drive control signals can control the voltages output by the data signal output ends of the liquid crystal driver 10 in time periods within the time period T, to control grayscales of each row of pixel electrodes on the electrode plate 20 shown in FIG. 4. The time period T is the display refresh period of the liquid crystal display. It is assumed that the processor 11 sends four groups of drive control signals to the liquid crystal driver 10. A first group of drive control signals controls voltages output by the data signal output ends of the liquid crystal driver 10 in the time period t1 within the time period T. A second group of drive control signals controls voltages output by the data signal output ends of the liquid crystal driver 10 in the time period t2 within the time period T. A third group of drive control signals controls voltages output by the data signal output ends of the liquid crystal driver 10 in the time period t3 within the time period T. A fourth group of drive control signals controls voltages output by the data signal output ends of the liquid crystal driver 10 in a time period t4 within the time period T. At least two of the plurality of groups of drive control signals sent each time by the processor 11 are different. For example, the processor 11 sends two groups of drive control signals: drive control signals A and drive control signals B to the liquid crystal driver 10 at one time, and the two groups of drive control signals are different. In addition, each group of drive control signals may be divided into a plurality of control groups. A quantity of control groups divided by the drive control signals is the same as the quantity of data signal transmission ends of the liquid crystal driver 10 (that is, the same as a quantity of one row of pixel electrodes on the electrode plate 20). One of the plurality of control groups is used to control voltages output by one of the data signal output ends (that is, control a grayscale of one of the pixel electrodes). For example, the electrode plate 20 shown in FIG. 3 is provided with the 320 data signal output ends s1 to s320, and one group of drive control signals may be divided into 320 control groups. Further, each control group may include a multi-bit signal. The multi-bit signal is used to control each data signal output end to output a specific voltage value. It is assumed that each control group includes a 6-bit signal, and each control group can control each data signal output end of the liquid crystal driver 10, to output voltages of 64 different voltage values. For example, "000000" represents an output voltage of 0 V, and "000001" represents an output voltage of 0.1 V In this way, the processor 11 sends different drive control signals to the liquid crystal driver 10, so that the liquid crystal driver 10 can apply voltages of different magnitudes to pixels on the electrode plate 20 within the time period T. Consequently, the liquid crystal molecules deflect based on an effective voltage of the time period T, to generate more grayscale values. For example, it is assumed that each control group includes the 6-bit signal. When the processor 11 sends a group of drive control signals to drive the liquid crystal molecules to deflect within one time period T, a 64-bit grayscale value may be generated. When the processor 11 sends two groups of different drive control signals to drive the liquid crystal molecules to deflect within one time period T, a grayscale value of 64×2-1=127 bits may be generated. It is equivalent to a drive signal with an increase of one bit accuracy within one time period T compared with the 6-bit signal. When the processor 11 sends four groups of different drive control signals to drive the liquid crystal molecules to deflect within one time period T, a grayscale value of 64×4-1=255 bits. It is equivalent to a drive signal with an increase of two-bit accuracy within one time period T compared with the 6-bit signal. It should be noted that in this embodiment of this application, a quantity of groups of drive control signals sent by the processor 11 can be set based on a display requirement of the liquid crystal display, to drive the liquid crystal molecules to deflect within each time period T. This is not specifically limited in this embodiment of this application. When the display image needs to be finer, more groups of different drive control signals can be sent within one time period T.

[0044] Based on the processor 11 and the working principle of the liquid crystal driver 10, a specific structure of the liquid crystal driver 10 is shown in FIG. 5. In FIG. 5, the liquid crystal driver 10 includes a digital-to-analog converter 101, a memory 102, a time sequence controller 103, and an interface 104. For example, the interface 104 may be a serial peripheral interface (serial peripheral interface, SPI). The liquid crystal driver 10 is coupled to the processor 11 by using the interface 104 for signal transmission. The memory 102 is separately coupled to the interface 104 and the digital-to-analog converter 101. Similarly, the time sequence controller 103 is also coupled to the digital-to-analog converter 101. The processor 11 writes the plurality of groups of drive control signals to the memory 102 by using the interface 104. The digital-to-analog converter 101 reads a drive control signal from the memory 102 based on a clock signal generated by the time sequence controller 103, converts the read drive control signal into an analog voltage signal, and transmits the voltage signal to the pixel electrodes on the electrode plate 20 by controlling the signal output ends s1 to s320. During specific implementation, based on accuracy of a grayscale to be generated by the liquid crystal display 200 and a display refresh period T of the liquid crystal display 200, a clock period of the time sequence controller 103 is set in advance. For example, each control group includes the 6-bit signal. If a 127-bit grayscale value needs to be generated, the clock period of the time sequence controller 103 may be 2/T. If a 255-bit grayscale value needs to be generated, the clock period of the time sequence controller 103 may be 4/T. Consequently, the digital-to-analog converter 101 reads a drive control signal from the memory 102 at a start moment of each clock period, and converts the read drive control signal 102 into a voltage signal. In addition, a manner for controlling voltage polarity reversal may be set in advance in the time sequence controller 103. In this embodiment of this application, a manner of reversing a voltage polarity can be set by various different methods such as a point-driven manner (that is, voltages of different polarities are applied to adjacent pixel electrodes within a same time period T), a column-driven manner (that is, the voltages of different polarities are applied to pixel electrodes in an adjacent column within the same time period T), a row-driven manner (that is, the voltages of different polarities are applied to pixel electrodes in an adjacent row within the same time period T) or a frame-driven manner (that is, a positive voltage is applied to all pixel electrodes within the first time period T, and a negative voltage is applied to all pixel electrodes within the second time period T). The following uses the frame-driven method as an example for description. It is assumed that a clock in the liquid crystal display 200 keeps presenting an image of a frame f1. The processor 11 stores two groups of drive control signals for presenting the image of the frame f1 in advance into the memory 102 by using the interface 104. The liquid crystal driver 10 converts the two groups of drive control signals into positive voltage signals within the first time period T based on a time sequence provided by the time sequence controller 103, provides the two groups of drive control signals to the pixel electrodes on the electrode plate 20, converts the two groups of drive control signals into negative voltage signals within the second time period T, and reciprocates in sequence until a screen goes out or the next time when the drive control signals arrive. It is assumed that a video is currently playing in the liquid crystal display 200. Based on a preset frame rate, the processor 11 may store two groups of drive control signals for presenting each frame into the memory 102 by using the interface 104. The liquid crystal driver 10 reads a group of drive control signals at a first T/2 within the first time period T based on a clock signal provided by the time sequence controller 103, converts the group of drive control signals into positive voltage signals, and provides the group of drive control signals to the pixel electrodes; reads a group of drive control signals at a later T/2 within the first time period T, converts the group of drive control signals into positive voltage signals, and provides the group of drive control signals to the pixel electrodes; reads a group of drive control signals at a first T/2 of the second time period T, converts the group of drive control signals into negative voltage signals, and provides the group of drive control signals to the pixel electrodes; reads a group of drive control signals at a latter T/2 of the second time period T, converts the group of drive control signals into negative voltage signals, and provides the group of drive control signals to the pixel electrode; and reciprocates in sequence until completion of video play. In addition, the liquid crystal driver 10 may further include more components. For example, the liquid crystal driver 10 further includes a direct current-direct current converter 105 that is connected to the power management integrated circuit 13 on the liquid crystal drive apparatus 100. The direct current-direct current converter 105 includes but is not limited to a buck converter, a boost converter, a buck-boost converter, or the like. The direct current-direct current converter 105 is configured to convert a direct current supplied by the power management integrated circuit 13 into a voltage and a current suitable for operation of the digital-to-analog converter 101, to supply power to the digital-to-analog converter 101.

[0045] Based on the structure of the liquid crystal driver 10 shown in FIG. 5, a specific structure of the digital-to-analog converter 101 in the liquid crystal driver 10 may be shown in FIG. 6. In FIG. 6, the digital-to-analog converter 101 includes a plurality of voltage divider resistors and a plurality of signal output channels that are connected in series between a power supply end Vdd and a common ground Gnd. Anode is disposed between every two of the plurality of voltage divider resistors to perform voltage division. A quantity of voltage divider resistors is determined based on a quantity of bits included in one control group in the drive control signal. FIG. 6 shows an example that 65 voltage divider resistors (five voltage divider resistors r1, r2, r3, r64, and r65 are shown in FIG. 6) are connected in series between the power supply end Vdd and the common ground Gnd. That is, a 64-bit voltage may be obtained through division, and a control group in a corresponding drive control signal includes a 6-bit signal. A quantity of signal output channels is the same as the quantity of pixels in each row on the electrode plate 20, and the plurality of signal output channels output a specific voltage to the pixels on the electrode plate 20 by using corresponding data signal output ends. For example, the liquid crystal driver 10 shown in FIG. 3 includes 320 data signal output ends, and the liquid crystal driver 10 may include 320 signal output channels. Each of the plurality of signal output channels includes a multiplexer M and a buffer F. Each multiplexer M includes a plurality of input ends. A quantity of the plurality of input ends is the same as a quantity of bits of a voltage that can be divided by the voltage divider resistor. Each multiplexer M shown in FIG. 6 may be a 64-to-1 selector, and the plurality of input ends of the multiplexer M are separately coupled to a voltage divider node. An output end of the multiplexer M is coupled to the data signal output end of the liquid crystal driver 10 by using the buffer F. In addition, an output end of the direct current-direct current converter shown in FIG. 4 is coupled to the power supply end Vdd, to supply power to Vdd. The buffer F may be a follower, the output end of the multiplexer M is coupled to an in-phase input end of the buffer F, and an inverting input end of the buffer F is coupled to an output end of the buffer F. In the digital-to-analog converter 101 shown in FIG. 5, each multiplexer M further includes a control end co, and the control end co is configured to input the drive control signal. Consequently, the multiplexer M selects an input end from the plurality of input ends to connect to the output end of the buffer F, that is, selects a voltage value. A control end co of each multiplexer is coupled to the memory 102 shown in FIG. 5 by using a bus, to obtain the drive control signal from the memory 102.

[0046] Based on the foregoing structure of the liquid crystal drive apparatus 100, an embodiment of this application further provides a liquid crystal driving method 700. The liquid crystal driving method 700 is applied to the liquid crystal drive apparatus 100 shown in FIG. 3. The liquid crystal driving method 700 specifically includes the following steps: Step 701: A processor 11 sends a first drive control signal to a liquid crystal driver 10. Step 702: The liquid crystal driver 10 converts the first drive control signal into a plurality of groups of first voltage signals, where each of the plurality of groups of first voltage signals includes a plurality of first voltages, and the plurality of first voltages are in a one-to-one correspondence with a plurality of pixels in a liquid crystal display; and outputs the plurality of groups of first voltage signals to a plurality of electrodes of the plurality of pixels in a time division manner within a first preset time period, to control grayscales of the plurality of pixels. Each group of first voltage signals is output in a period of time within the first preset time period, each of the plurality of first voltages is used to control a grayscale of a pixel corresponding to the first voltage, and at least two of the plurality of groups of first voltage signals are different.

[0047] In a possible implementation, the first drive control signal includes a plurality of groups of first drive control signals; and that the liquid crystal driver 10 converts the first drive control signal into a plurality of groups of first voltage signals includes: The liquid crystal driver 10 converts each of the plurality of groups of first drive control signals into one group of first voltage signals.

[0048] In a possible implementation, that a processor 11 sends a first drive control signal to a liquid crystal driver 10 includes: storing the plurality of groups of first drive control signals into a memory 102 in the liquid crystal driver 10 when the liquid crystal drive apparatus 100 is powered on, when the liquid crystal display 200 is lit up, during a video play process, or when a display image is switched.

[0049] In a possible implementation, that the liquid crystal driver 10 converts the first drive control signal into a plurality of groups of first voltage signals includes: Based on a clock signal generated by a time sequence controller 103 in the liquid crystal driver 10, the liquid crystal driver 10 reads the plurality of groups of first drive control signals from the memory 102 in a time division manner within the first preset time period, and converts the plurality of groups of first drive control signals into the plurality of groups of first voltage signals, where the first preset time period includes a plurality of clock periods of the clock signal.

[0050] In a possible implementation, within the first preset time period, the plurality of first voltages are positive voltage signals; and the method further includes: The processor 11 sends a second drive control signal to the liquid crystal driver 10. The liquid crystal driver 10 converts the second drive control signal into a plurality of groups of second voltage signals, where each of the plurality of groups of second voltage signals includes a plurality of second voltages, and the plurality of second voltages are in a one-to-one correspondence with the plurality of pixels; and outputs the plurality of groups of second voltage signals to the plurality of electrodes in a time division manner within a second preset time period. Each group of second voltage signals is output in a period of time within the second preset time period, each of the plurality of second voltages is used to control a grayscale of a pixel corresponding to the second voltage, and at least two of the plurality of groups of second voltage signals are different. Within the second preset time period, the plurality of second voltages are negative voltage signals.

[0051] In a possible implementation, the at least two groups of first voltage signals include a first group of first voltage signals and a second group of first voltage signals; and a first voltage for a pixel in the first group of first voltage signals is different from a first voltage for the pixel in the second group of first voltage signals.

[0052] In a possible implementation, a first voltage for a pixel in any one of the at least two groups of first voltage signals is different from a first voltage for the pixel in any other one of the at least two groups of first voltage signals.

[0053] In a possible implementation, the first preset time period is a display refresh period of the liquid crystal display.

[0054] Finally, it should be noted that the foregoing embodiments are merely intended for describing the technical solutions of this application, but not for limiting this application. Although this application is described in detail with reference to the foregoing embodiments, a person of ordinary skill in the art should understand that modifications may still be made to the technical solutions described in the foregoing embodiments or equivalent replacements may be made to some or all technical features thereof, without departing from the scope of the technical solutions of embodiments of this application.

Claims

1. A liquid crystal drive apparatus, comprising a processor and a liquid crystal driver, wherein

the processor is configured to send a first drive control signal to the liquid crystal driver; and

the liquid crystal driver is configured to: convert the first drive control signal into a plurality of groups of first voltage signals, wherein each of the plurality of groups of first voltage signals comprises a plurality of first voltages, and the plurality of first voltages are in a one-to-one correspondence with a plurality of pixels in a liquid crystal display; and output the plurality of groups of first voltage signals to a plurality of electrodes of the plurality of pixels in a time division manner within a first preset time period, to control grayscales of the plurality of pixels, wherein

each group of first voltage signals is output in a period of time within the first preset time period, each of the plurality of first voltages is used to control a grayscale of a pixel corresponding to the first voltage, and at least two of the plurality of groups of first voltage signals are different.

2. The liquid crystal drive apparatus according to claim 1, wherein the first drive control signal comprises a plurality of groups of first drive control signals, and the liquid crystal driver comprises a digital-to-analog conversion circuit; and
the digital-to-analog conversion circuit is configured to convert each of the plurality of groups of first drive control signals into one group of first voltage signals.

3. The liquid crystal drive apparatus according to claim 2, wherein the liquid crystal driver further comprises a memory, and the processor is specifically configured to:
store the plurality of groups of first drive control signals into the memory after the liquid crystal drive apparatus is powered on, when the liquid crystal display is lit up, during a video play process, or when a display image is switched.

4. The liquid crystal drive apparatus according to claim 3, wherein the liquid crystal driver further comprises a time sequence controller, the time sequence controller is configured to generate a clock signal, and the first preset time period comprises a plurality of clock periods of the clock signal; and
the liquid crystal driver is specifically configured to: based on the clock signal, read the plurality of groups of first drive control signals from the memory in the time division manner within the first preset time period; and convert the plurality of groups of first drive control signals into the plurality of groups of first voltage signals.

5. The liquid crystal drive apparatus according to claim 3 or 4, wherein

within the first preset time period, the plurality of first voltages are positive voltage signals;

the processor is further configured to send a second drive control signal to the liquid crystal driver;

the liquid crystal driver is further configured to: convert the second drive control signal into a plurality of groups of second voltage signals, wherein each of the plurality of groups of second voltage signals comprises a plurality of second voltages, and the plurality of second voltages are in a one-to-one correspondence with the plurality of pixels; and output the plurality of groups of second voltage signals to the plurality of electrodes in the time division manner within a second preset time period, wherein each group of second voltage signals is output in a period of time within the second preset time period, each of the plurality of second voltages is used to control a grayscale of a pixel corresponding to the second voltage, and at least two of the plurality of groups of second voltage signals are different; and

within the second preset time period, the plurality of second voltages are negative voltage signals.

6. The liquid crystal drive apparatus according to any one of claims 1 to 5, wherein the at least two groups of first voltage signals comprise a first group of first voltage signals and a second group of first voltage signals; and
a first voltage for a pixel in the first group of first voltage signals is different from a first voltage for the pixel in the second group of first voltage signals.

7. The liquid crystal drive apparatus according to any one of claims 1 to 6, wherein a first voltage for a pixel in any one of the at least two groups of first voltage signals is different from a first voltage for the pixel in any other one of the at least two groups of first voltage signals.

8. The liquid crystal drive apparatus according to any one of claims 1 to 7, wherein the liquid crystal drive apparatus further comprises the liquid crystal display.

9. The liquid crystal drive apparatus according to any one of claims 1 to 8, wherein the first preset time period is a display refresh period of the liquid crystal display.

10. A method for driving a liquid crystal, wherein the method comprises:

sending, by a processor in a liquid crystal drive apparatus, a first drive control signal to a liquid crystal driver; and

converting, by the liquid crystal driver in the liquid crystal drive apparatus, the first drive control signal into a plurality of groups of first voltage signals, wherein each of the plurality of groups of first voltage signals comprises a plurality of first voltages, and the plurality of first voltages are in a one-to-one correspondence with a plurality of pixels in a liquid crystal display; and outputting the plurality of groups of first voltage signals to a plurality of electrodes of the plurality of pixels in a time division manner within a first preset time period, to control grayscales of the plurality of pixels, wherein

each group of first voltage signals is output in a period of time within the first preset time period, each of the plurality of first voltages is used to control a grayscale of a pixel corresponding to the first voltage, and at least two of the plurality of groups of first voltage signals are different.

11. The method according to claim 10, wherein the first drive control signal comprises a plurality of groups of first drive control signals; and the converting, by the liquid crystal driver in the liquid crystal drive apparatus, the first drive control signal into a plurality of groups of first voltage signals comprises:
converting, by the liquid crystal driver, each of the plurality of groups of first drive control signals into one group of first voltage signals.

12. The method according to claim 11, wherein the sending, by a processor in a liquid crystal drive apparatus, a first drive control signal to a liquid crystal driver comprises:
storing the plurality of groups of first drive control signals into a memory in the liquid crystal driver after the liquid crystal drive apparatus is powered on, when the liquid crystal display is lit up, during a video play process, or when a display image is switched.

13. The method according to claim 12, wherein the converting, by the liquid crystal driver in the liquid crystal drive apparatus, the first drive control signal into a plurality of groups of first voltage signals comprises:

reading, by the liquid crystal driver based on a clock signal generated by a time sequence controller in the liquid crystal driver, the plurality of groups of first drive control signals from the memory in the time division manner within the first preset time period, and converting the plurality of groups of first drive control signals into the plurality of groups of first voltage signals, wherein

the first preset time period comprises a plurality of clock periods of the clock signal.

14. The method according to claim 12 or 13, wherein within the first preset time period, the plurality of first voltages are positive voltage signals; and the method further comprises:

sending, by the processor, a second drive control signal to the liquid crystal driver; and

converting, by the liquid crystal driver, the second drive control signal into a plurality of groups of second voltage signals, wherein each of the plurality of groups of second voltage signals comprises a plurality of second voltages, and the plurality of second voltages are in a one-to-one correspondence with the plurality of pixels; and outputting the plurality of groups of second voltage signals to the plurality of electrodes in the time division manner within a second preset time period, wherein each group of second voltage signals is output in a period of time within the second preset time period, each of the plurality of second voltages is used to control a grayscale of a pixel corresponding to the second voltage, and at least two of the plurality of groups of second voltage signals are different; and

within the second preset time period, the plurality of second voltages are negative voltage signals.

15. The method according to any one of claims 10 to 14, wherein the at least two groups of first voltage signals comprise a first group of first voltage signals and a second group of first voltage signals; and
a first voltage for a pixel in the first group of first voltage signals is different from a first voltage for the pixel in the second group of first voltage signals.

16. The method according to any one of claims 10 to 15, wherein a first voltage for a pixel in any one of the at least two groups of first voltage signals is different from a first voltage for the pixel in any other one of the at least two groups of first voltage signals.

17. The method according to any one of claims 10 to 16, wherein the first preset time period is a display refresh period of the liquid crystal display.

Drawing