Electrophoretic display driving method and device

Abstract

The invention discloses an electrophoretic display driving method and device, and can effectively solve the problem that in the prior art, due to the fact that the driving form is too complex, the data processing and storage efficiency is poor. The method comprises the following steps: acquiring a corresponding relationship between each pixel and a display unit of the display device; obtaining a first binary value corresponding to the gray scale of any pixel in the current frame image; acquiring a second binary value corresponding to the gray scale of the pixel in the next frame of image; calculating a difference value between the second binary value and the first binary value of the pixel; generating a first driving waveform lookup table according to the corresponding relation and the difference value; and driving each display unit according to the first driving waveform lookup table.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electronic paper display, in particular to a driving method and device of electrophoretic display. BACKGROUND

[0002] Electronic paper display technology is a new type of reflective display mode, compared with the traditional display mode, it has high reflectivity, low power consumption, high contrast, long-lasting and other advantages, it is a new type of electronic device that can replace paper for reading.

[0003] At present, the electronic paper display device based on electrophoresis technology is studied more, especially the electronic paper display device based on microcapsule electrophoresis technology. The electronic paper display device is generally formed by pasting the upper and lower substrates, and the electrophoretic particle film is filled therebetween. There is a common electrode on the upper substrate, and a pixel electrode on the lower substrate. The pixel electrodes are generally arranged in a matrix. Each pixel electrode corresponds to a pixel. For active electronic paper display, the thin film transistor (TFT) active substrate is commonly used for the lower substrate. The drain electrode in the TFT is connected to the pixel electrode through a via hole. The source electrode in the TFT is connected to the data line. The gate electrode in the TFT is connected to the gate bus. Based on the above structure, the gate bus controls the selection of each pixel. When the gate electrode is connected to the selection voltage, the drain electrode and the source electrode are turned on through the active layer. Then the pixel electrode is applied with a voltage by the data line. In combination with the common voltage on the common electrode, the electrophoretic particles are driven to move to different positions by the length of time of applying electric field between the pixel electrode and the common electrode of the upper substrate, thereby realizing black and white gray scale display.

[0004] Electronic paper driving is generally divided into reset phase and display phase. In the reset phase, one-way reset is performed, that is, only reset in the black or white direction. In the display phase, image display is performed according to the state after reset. In the traditional driving method, first, two synchronous dynamic random access memories (SDRAMs) store the image data of the previous frame and the next frame respectively. In driving, the corresponding waveform is read from the look-up table (LUT) of the flash according to the data at the same position in the SDRAM for driving. The form of the stored waveform is a sequence composed of -1, 1 and 0, wherein -1, 1 and 0 respectively represent the driving voltage of the data line as -15V, +15V and 0V. If the driving is divided into 64 sub-frame reset and 64 sub-frame display (here, “sub-frame” refers to the process of scanning from the first row to the last row of the gate electrode), the corresponding waveform is a sequence of 128 bits. The sequence data corresponding to the traditional waveform has many bits, which is relatively complex in data processing and storage.

[0005] For example, before driving each subframe, it is necessary to first find out from the waveform whether the subframe corresponds to -1, 1 or 0, so as to determine the level of the subframe. The whole process is very cumbersome. In addition, since all waveforms need to be stored in a large capacity flash memory, there are also certain requirements for the space capacity of the flash memory. Figure 1 This illustrates a schematic diagram of image data storage in the prior art, such as... Figure 1 As shown, SDRAM1 and SDRAM2 are used to store the image data of the previous frame and the next frame, respectively (the image data of the previous frame and the next frame can also be stored in the same SDRAM, and SDRAM1 and SDRAM2 are represented as two storage areas respectively). The image data of each pixel is stored separately, such as data1, data2, ... up to dataN. First, after powering on, the electronic paper needs to be initialized to provide a good reference value for subsequent image display. For example, after initialization, all data in SDRAM1 is set to 0, and the first frame image data is stored in SDRAM2. When displaying the first frame image, SDRAM2 is compared with SDRAM1, a lookup table is consulted, and the image is displayed. At the same time, the first frame image data (the first frame image, after being displayed, is the previous frame image relative to the second frame image to be displayed, and is also called the previous frame image data) is stored in SDRAM1. The second frame image data (the next frame image data) is stored in SDRAM2. When displaying the second frame image, SDRAM2 is compared with SDRAM1, a lookup table is consulted, and the image is displayed. SDRAM1 stores the current image. The next frame image data to be displayed is stored in SDRAM2, and so on. By repeating this process, the desired display image can be output.

[0006] Figure 2 This is a schematic diagram of the storage structure of a lookup table in existing technology. (See also...) Figure 2The horizontal axis, from "0" to "7", indicates the grayscale of the previous frame, and the vertical axis, from "0" to "7", indicates the grayscale of the next frame. This forms an 8x8 lookup table with 8 grayscale levels, where grayscale 0 represents white and grayscale 7 represents black. For example, if a pixel's grayscale data in the previous frame is 3 and its grayscale data in the next frame is 2, the lookup table can be consulted to find the data containing 3 and 2. The display output is then driven based on the data containing 3 and 2. Assuming the displayed image has 8 grayscale levels and the entire drive is divided into 64 subframes for reset and 64 subframes for display, totaling 128 subframes, the required flash memory capacity for the corresponding lookup table is at least 128 * 2 * (8 * 8) = 16384 bits (using -1, 1, and 0 to represent the driving voltage on the corresponding data lines, which needs to be represented by two binary bits). If the driving direction "01" represents 0V, "10" represents +15V, and "11" represents -15V, and assuming that in the 128 subframes of the entire drive, a pixel needs 32 subframes to reset from grayscale 3, 22 subframes to display at grayscale 2, and the rest are in the maintenance phase, then the representation of the driving data would be as follows:

[0007] 1111......1111 (32 groups of "11") 0101......0101 (32 groups of "01") 1010......1010 (22 groups of "10") 0101......0101 (42 groups of "01"), and the storage space required for this driving waveform is 32*2+32*2+22*2+42*2=256 bits (corresponding to Figure 2 (A cell in the lookup table shown). Summary of the Invention

[0008] The problem this invention aims to solve is that the existing technology suffers from poor efficiency in data processing and storage due to the overly complex driving mechanism.

[0009] This invention provides an electrophoretic display driving method, comprising:

[0010] Obtain the correspondence between each pixel and its display unit on the display device;

[0011] Get the first binary value corresponding to the gray level of any pixel in the current frame image;

[0012] Obtain the second binary value corresponding to the grayscale of the pixel in the next frame image;

[0013] Calculate the difference between the second binary value and the first binary value of the pixel;

[0014] A first drive waveform lookup table is generated based on the correspondence and the difference;

[0015] Each display unit is driven according to the first drive waveform lookup table.

[0016] Optional,

[0017] The first drive waveform lookup table includes drive waveforms that correspond one-to-one with the differences;

[0018] The number of non-zero main pulses in the driving waveform is related to the difference, and the direction corresponds to the sign of the difference.

[0019] Optional,

[0020] The main pulse includes pulses used to drive the target grayscale error to a value of ±10 luminance units.

[0021] Optional,

[0022] Obtain temperature information:

[0023] A second drive waveform lookup table is generated based on the temperature information, the correspondence, and the difference.

[0024] Optional,

[0025] Calculate the pulse direction value based on the second binary value and the first binary value;

[0026] A third drive waveform lookup table is generated based on the pulse direction value, the corresponding relationship, and the difference.

[0027] Optional,

[0028] Groups are created for a predetermined number of adjacent pixels, and each group contains the same number of pixels;

[0029] Assign a group number to each pixel within the group;

[0030] Optional,

[0031] The step of creating groups for a predetermined number of adjacent pixels and assigning group numbers also includes:

[0032] Assign a group number to each group;

[0033] Store all groups according to the group number.

[0034] Optionally, each display unit is driven according to the fourth drive waveform lookup table; the remaining display units in the group are also driven according to the fourth drive waveform lookup table.

[0035] Another aspect of the present invention provides an electrophoretic display driving device that applies the electrophoretic display driving method described above, the device comprising:

[0036] The first acquisition unit is used to acquire the correspondence between each pixel and its display unit on the display device;

[0037] The second acquisition unit is used to acquire the first binary value corresponding to the gray level of any pixel in the current frame image;

[0038] The third acquisition unit is used to acquire the second binary value corresponding to the gray level of the pixel in the next frame image;

[0039] The first calculation unit is used to calculate the difference between the second binary value and the first binary value of the pixel;

[0040] The first generation unit is used to generate a first driving waveform lookup table based on the correspondence and the difference;

[0041] The first driving unit is used to drive each display unit according to the first driving waveform lookup table.

[0042] Optionally, the device includes:

[0043] A grouping unit is used to create groups of a predetermined number of adjacent pixels, wherein each group contains the same number of pixels;

[0044] The first allocation unit is used to assign a group number to each pixel within the group;

[0045] The second generation unit is used to generate a fourth driving waveform lookup table based on the group number, correspondence, and difference.

[0046] Optionally, the device includes:

[0047] The second allocation unit is used to assign a group number to each group;

[0048] A storage unit for storing all groups according to the group number.

[0049] Optionally, the device includes:

[0050] The second driving unit is used to drive each display unit according to the fourth driving waveform lookup table;

[0051] The third driving unit is used to drive the remaining display units in the group according to the fourth driving waveform lookup table.

[0052] Compared with the prior art, the present invention has the following advantages:

[0053] By optimizing the data processing methods, the data processing process is greatly simplified, thereby improving the efficiency of data processing. By changing the data storage format of the waveform, the storage space required by flash memory is reduced, thereby achieving the goal of reducing costs. Attached Figure Description

[0054] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0055] Figure 1 This is a schematic diagram of the existing SDRAM storage structure;

[0056] Figure 2 This refers to the existing SDRAM storage table;

[0057] Figure 3 A flowchart illustrating an embodiment of the electrophoretic display driving method provided by the present invention;

[0058] Figure 4 A flowchart of another embodiment of the electrophoretic display driving method provided by the present invention;

[0059] Figure 5 This is a schematic diagram of the structure of an embodiment of the electrophoretic display driving device provided by the present invention;

[0060] Figure 6 This is a schematic diagram of the pixel group structure of the present invention. Detailed Implementation

[0061] The technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0062] In this document, the term "comprising" is intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0063] In this embodiment, the electrophoretic display includes: an electronic paper film (EPD), an electrowetting display (EWD), a cholesterol liquid crystal display (CLCD), or other bistable display panels, but the present invention is not limited thereto.

[0064] In this embodiment, the core element of the electronic paper film is the electrophoretic pigment particles. Their particle size distribution, surface morphology, zeta potential, optical properties, and chemical properties all play a crucial role in the contrast, response time, clarity, and lifespan of the electronic paper. This electrophoretic display technology utilizes the electrophoresis principle from colloid chemistry to stably disperse charged pigment particles in a non-aqueous dispersion medium containing dyes. This creates a contrast between the dispersed phase and the dispersion medium. Under the influence of an electric field, charged pigment ions migrate to the electrode surface, thus displaying an image.

[0065] In this embodiment, one structure of the electrophoretic pigment particles includes a core and a shell. The core is a pigment particle, and the shell includes a polymer and a coupling agent that couples the polymer and the pigment particles. The pigment particles include positively charged pigment particles, negatively charged pigment particles, or neutral pigment particles, specifically one or a combination of two or more of the following: carbon black, copper chromium black, copper iron manganese black, iron black, titanium dioxide, zinc white, barium sulfate, iron oxide red, iron oxide yellow, ultramarine, chrome yellow, cadmium red, manganese violet, chrome green, iron blue, and cobalt blue. The coupling agent is one or a combination of two or more of the following: 3-aminopropyltriethoxysilane (KH550), γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH560), γ-(methacryloyloxy)propyltrimethoxysilane (KH570), γ-mercaptopropyltrimethoxysilane (KH580), N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane (KH792), vinylbenzylaminoethylaminopropyltrimethoxysilane (VAPMS), and isopropyltrioleoyloxytitanate. To ensure that the average particle size of the electrophoretic pigment particles meets the requirements, the applicant needs to perform micronization treatment on the electrophoretic pigment particles. In practical applications, methods such as grinding, pulverizing, ultrasonication, or solvent dispersion can be used to achieve this. Related equipment may include colloid mills, ball mills, cryogenic pulverizers, and ultrasonic machines.

[0066] The main components of the electrophoretic solution include, but are not limited to, dispersants, thickeners, surface tension control agents, and charge control agents. Dispersants include various nonpolar and / or low-polar organic solvents and mixtures thereof. Low-polar dispersants include, but are not limited to, various aromatic hydrocarbons such as toluene, benzene, and xylene, as well as halogenated hydrocarbons such as, but not limited to, chloroform and tetrachloroethylene. Nonpolar dispersants include, but are not limited to, straight-chain, branched, and cyclic aliphatic hydrocarbons, such as n-hexane, nonane, decanane, synthetic isoparaffin (Isopar), synthetic paraffin (Norpar), synthetic cycloalkanes (Nappar), synthetic alkanes (Varsol / Naphtha), cyclohexane, and halogenated hydrocarbons such as carbon tetrachloride. Thickeners can be nonpolar polymers, including, but not limited to, polymethyl methacrylate. Methyl methacrylate, polyethylene, polypropylene, and rubbers such as polyisoprene and polyisobutylene are suitable materials, with polymethyl methacrylate, polyisoprene, and polyisobutylene being the best choices. Surface tension control agents can be one or a combination of two or more of the following: glyceryl monostearate, ethyl distearate-based hydroxyethyl methyl sulfate ammonium, ethyl tripearate-based hydroxyethyl methyl sulfate ammonium, Span20, Span40, Span60, Span80, Tween85, and alkyl tertiary amine salts. Charge control agents can be organic sulfates, sulfonates, metal soaps, organic amides, organophosphates, or phosphates, and can also be polymers and block or graft copolymers, as well as their monomers. Polyisobutylene succinimide, metal saponins, and lecithin polyisobutylene or organosilicon derivatives can be used as charge control agents.

[0067] The electrophoretic solution and the electrophoretic pigment particles dispersed in the electrophoretic solution are encapsulated within the display unit, thereby effectively inhibiting the aggregation of the electrophoretic pigment particles and improving the stability and lifespan of the electrophoretic display. In this embodiment, the display unit may include at least one of microcapsules and microcups. The microcapsule in this embodiment includes the aforementioned electrophoretic solution, electrophoretic pigment particles dispersed in the electrophoretic solution, and at least one capsule wall, wherein the capsule wall is formed by a complex coagulation method or an in-situ polymerization method. It should be noted that in-situ polymerization can also be called interfacial polymerization, using urea-formaldehyde resin or modified urea-formaldehyde resin as the microcapsule wall material; the complex coagulation method uses gelatin and gum arabic as the microcapsule wall material. The microcup in this embodiment includes an electrophoretic solution, electrophoretic pigment particles dispersed in the electrophoretic solution, and a microcup. The microcup can be a small, hollow, and sealed cylinder. The microcup is formed by microcup roller die casting and UV curing, and then the electrophoretic pigment particles in the electrophoretic solution are encapsulated in the microcup using a specific method.

[0068] The electrophoretic display structure in this embodiment includes, but is not limited to, a display layer containing a curing medium, an electrophoretic liquid distributed in the curing medium, and at least one electrophoretic pigment particle dispersed in the electrophoretic liquid; the display layer is connected to the transparent conductive layer by an adhesive.

[0069] One preparation method of the display layer in this embodiment is to mix a transparent adhesive, a display unit containing electrophoresis liquid such as microcapsules or microcups, and other solvents in a predetermined ratio, stir the obtained mixture evenly, and then coat it on a substrate. In the actual processing process, the mixture can be coated on the substrate by a slit extrusion coating process. The slit extrusion coating process can be that the coating material is pressurized by a metering pump, extruded from the extrusion outlet of the coating die head, and coated on the surface of the substrate. The thickness of the coating layer can be determined according to the coating extrusion amount of the coating die head and the running speed of the substrate. The applicant can preset the gap of the extrusion outlet and the distance between the extrusion outlet and the back roller, so as to control this process. Then it enters the curing process. It can be understood that the curing process can be achieved at room temperature. In order to accelerate the curing speed, rapid curing can be achieved by conventional curing means such as heating, air box drying or light curing. It is worth noting that coating methods such as knife coating, casting coating, brush coating, roll coating, spraying, powder coating, etc., as well as screen printing and inkjet printing processes can also be used to replace the slit extrusion coating process. The adhesives mentioned in this embodiment include aqueous polyurethane emulsion or solvent-based polyurethane emulsion, specifically including but not limited to one or more combinations of polyester diol, polyether diol, polyethylene glycol, small molecule chain extender and diisocyanate. The transparent conductive layer can be ITO (Indium Tin Oxides), also known as a semiconductor transparent conductive film, which is obtained by forming a transparent indium tin oxide (ITO) conductive thin film coating on a transparent organic thin film material such as PET (Polyethylene terephthalate), PE (polyethylene), PP (polypropylene), etc. and performing high-temperature annealing treatment. The preparation methods of ITO transparent conductive thin films include but are not limited to process methods such as evaporation, sputtering, reactive ion plating, chemical vapor deposition or pyrolytic spraying. In practical applications, ITO transparent conductive thin films can be replaced by conductive thin films such as graphene, silver powder or nanosilver wires. Since graphene has extremely high advantages in conductivity and hardness, it is suitable for making conductive films. The preparation methods of this graphene conductive film include but are not limited to chemical vapor deposition method and redox method. Chemical vapor deposition can obtain large-area single-layer graphene with good quality, and has performance advantages in light transmittance and sheet resistance, but has defects such as complex process route, high cost, low yield, and limited film area. The redox method adopts a solution process, which is convenient for large-area continuous preparation through a roll-to-roll process and has great advantages in cost. This silver powder conductive film uses silver conductor paste as the main material, in which silver powder is used as the conductive functional material, mainly utilizing the conductivity and thermal conductivity of silver powder. Silver powder can be divided into coarse silver powder and nanosilver wires according to the particle size. Among them, the average particle size <0.1μm is nanosilver wire; 0.1μm < Dav < 10.0μm is coarse silver powder.In addition to the excellent conductivity of silver, silver nanowires also possess superior light transmittance and flexibility due to their nanoscale size advantage, making them a preferred alternative to ITO. In this embodiment, the driving backplane can be a TFT glass substrate, FPC, or segment glass substrate. When using dot matrix display technology, a TFT glass substrate can be used.

[0070] In this embodiment, the electrophoretic solution includes n types of electrophoretic pigment particles C1, ..., Ck, ..., Cn, where n is a natural number of 2 or greater, and k = n-1. When n = 2, Ck is omitted. The charged particles C1, ..., Ck, ..., Cn have different colors and different threshold voltages for initiating electrophoresis. Each charged particle C1, ..., Ck, ..., Cn satisfies the following relationship: threshold voltage of charged particle C1 > ... > threshold voltage of charged particle Ck > ... > threshold voltage of charged particle Cn. Where k = n-1, and when n = 2, the kth voltage application period is omitted.

[0071] The voltage application unit is configured, during screen updates, for each specified voltage drive waveform to be applied, to cause the corresponding charged particles to electrophoretically migrate along the thickness direction of the electrophoretic layer at a predetermined distance less than or equal to the thickness "L" in response to the updated relative color density for each type of charged particle, in the order of charged particles C1→...→Ck→...→Cn, and ultimately update the screen to the next screen with multiple gray levels having more than or equal to three gray levels, wherein, if the order is not reversed, a given type or multiple types of charged particles can simultaneously transition to an intermediate transition state or a final display state.

[0072] Please see Figure 3 The electrophoretic display driving method provided by the present invention includes:

[0073] 101. Obtain the correspondence between each pixel and its display unit on the display device;

[0074] In this embodiment, the processor executes a matching program to obtain the correspondence between each pixel and its display unit on the display device.

[0075] It should be noted that the TFT interlacing, with each intersection point being the display unit, also known in the industry as a pixel. Because this is easily confused with pixels in an image, it is represented by display units in this invention. The image needs to be displayed on the display interface of the electrophoretic display device; therefore, there is a one-to-one correspondence between image pixels and image units. The corresponding image pixels can be recorded in the memory using the coordinates of the display units, or other marking methods, which will not be elaborated upon here.

[0076] 102. Obtain the first binary value corresponding to the grayscale of any pixel in the current frame image;

[0077] 103. Obtain the second binary value corresponding to the grayscale of the pixel in the next frame image;

[0078] In this embodiment, please refer to Figure 1 This illustrates a schematic diagram of image data storage in the prior art, such as... Figure 1 As shown, SDRAM1 and SDRAM2 are used to store the image data of the previous frame and the next frame, respectively (the image data of the previous frame and the next frame can also be stored in the same SDRAM, and SDRAM1 and SDRAM2 are represented as two storage areas respectively). The image data of each pixel is stored separately, such as data1, data2, ... up to dataN. First, after powering on, the electronic paper needs to be initialized to provide a good reference value for subsequent image display. For example, after initialization, all data in SDRAM1 is set to 0, and the first frame image data is stored in SDRAM2. When displaying the first frame image, SDRAM2 is compared with SDRAM1, a lookup table is consulted, and the image is displayed. At the same time, the first frame image data (the first frame image, after being displayed, is the previous frame image relative to the second frame image to be displayed, and is also called the previous frame image data) is stored in SDRAM1. The second frame image data (the next frame image data) is stored in SDRAM2. When displaying the second frame image, SDRAM2 is compared with SDRAM1, a lookup table is consulted, and the image is displayed. SDRAM1 stores the current image. The next frame image data to be displayed is stored in SDRAM2, and so on. By repeating this process, the desired display image can be output.

[0079] In this embodiment, we first take the electrophoretic display combining microcapsules and RGB filters as an example. Color particle electrophoretic display applications can also be applied to this method embodiment. In addition to displaying black and white, the microcapsules also support grayscale display modes, such as GC4, GC8, or GC16. Here, GC represents grayscale clear refresh, and 4, 8, and 16 represent the maximum number of gray levels supported by different modes. Currently, e-ink screens can support up to 16 grayscale levels. Taking GC16 mode as an example, this mode provides 16 grayscale display effects from 0 to 15. Level 0 corresponds to white, level 15 corresponds to black, and levels 1 to 14 correspond to different gray effects that deepen sequentially from white to black. Of course, in practical applications, there are solutions that define level 0 as black and level 15 as white; this application embodiment does not limit this. When displaying various grayscale levels between black and white, the black and white ink particles are no longer driven to the top or bottom of the microcapsule, but instead move and float at a certain position within the microcapsule to correspond to the grayscale display requirements of different grayscale levels.

[0080] When displaying an image frame, the RGB image is first converted to grayscale, transforming the RGB value of each pixel into 16 grayscale levels. Then, the timing controller circuit performs a lookup table (LUT) to obtain the driving waveform for each pixel. This waveform contains information such as the current / voltage, pulse duration, and pulse period required for displaying the current frame. After receiving the driving waveforms corresponding to all pixels in the current frame, the e-paper controller drives the microcapsules corresponding to each pixel in the e-ink screen according to the driving parameters carried by the waveforms. This controls the black and white ink particles in the microcapsules to move from the current position to the next position, thereby refreshing the e-ink screen to display the next image frame.

[0081] The LUT (Low-Unit Underlying Table) is an e-ink display driver mapping table obtained and recorded by the e-ink display supplier based on screen hardware testing. This table records the driving waveform used for each pixel under different display requirements / conditions. The dependent variables typically affecting the mapping table include: the grayscale value of the pixel in the next frame, the grayscale value of the pixel in the previous frame, and the current screen temperature. The grayscale value of the pixel in the next frame determines the position the ink particles should move to, while the grayscale value of the pixel in the previous frame corresponds to the current position of the ink particles. Screen temperature needs to be considered because the viscosity of the filling liquid in the microcapsules varies under different temperature conditions. Under the same driving waveform conditions, increased filling liquid viscosity increases the resistance to ink particle movement, resulting in insufficient movement distance and causing the screen display to be too dark or too light, affecting the display effect. Therefore, the driving waveform needs to be adjusted according to the current screen temperature to ensure that ink particles can move sufficiently to the designated position at different temperatures, achieving sufficient and accurate grayscale representation. Generally, the viscosity of the filling liquid is negatively correlated with temperature; that is, the lower the temperature, the higher the viscosity of the filling liquid.

[0082] The LUT table provides all possible combinations of the three parameters: "next frame grayscale value", "previous frame grayscale value", and "current screen temperature". Each combination is mapped to a corresponding driving waveform parameter, forming the mapping table mentioned above.

[0083] During the lookup process, the timing controller circuit retrieves the grayscale image of the next frame from the system-on-chip (SOC) and obtains the grayscale value of each pixel. Then, it retrieves the grayscale image of the previous frame from the buffer, similarly obtaining the grayscale value of each pixel in the previous frame. Next, the timing controller circuit queries the SOC for temperature data around the e-ink screen. This data is monitored and transmitted to the SOC by a temperature sensor located inside the terminal and close to the back panel of the e-ink screen. After obtaining the above data, the timing controller circuit uses these three data items as dependent variables and looks up the corresponding drive waveform in the LUT table. Once the drive waveform corresponding to each pixel in a frame of image is obtained, the lookup process is complete.

[0084] 104. Calculate the difference between the second binary value and the first binary value of the pixel;

[0085] 105. Generate a first drive waveform lookup table based on the correspondence and difference;

[0086] 106. Drive each display unit according to the first drive waveform lookup table.

[0087] In this embodiment, when the processor looks up the driving waveform corresponding to each pixel from the driving waveform lookup table, compared to the prior art where the driving waveform corresponding to each pixel is a string of binary data with 10 bits of new and old grayscale information, as shown in the table below:

[0088]

[0089] Table 1 is a prior art LUT table.

[0090] The first two columns from the left contain grayscale information from both the old and new images. N0-N4 represent 5-bit grayscale information from the new image, and O0-O4 represent 5-bit grayscale information from the old image. Compared to existing technologies, this method performs interpolation on the old and new grayscale information to obtain a 5-bit grayscale difference value. When processing each pixel, only the 5-bit grayscale difference value needs to be extracted and processed, significantly saving storage space and reducing processing speed.

[0091] In this embodiment, the correspondence between each pixel and its display unit on the display device is obtained; the first binary value corresponding to the grayscale of any pixel in the current frame image is obtained; and the second binary value corresponding to the grayscale of the pixel in the next frame image is obtained without any order limitation; then the difference between the second binary value and the first binary value of the pixel is calculated; then a first driving waveform lookup table is generated according to the correspondence and the difference; finally, each display unit is driven according to the first driving waveform lookup table. By optimizing the data processing method, the data processing process is greatly simplified to improve the efficiency of data processing. By changing the data storage format of the waveform, the storage space required by the flash memory is reduced, thereby achieving the purpose of reducing costs.

[0092] It should be noted that the first drive waveform lookup table includes drive waveforms that correspond one-to-one with the differences; the number of non-zero main pulses in the drive waveform is related to the differences, and furthermore, if the absolute values ​​of the differences are the same, the number of non-zero main pulses is also the same, and the direction of the main pulses is consistent with the sign of the differences. The aforementioned main pulses are configured to drive pulses with a target grayscale error of ±10 luminance units.

[0093] In this embodiment, the number of main pulses determines the magnitude of the difference between one gray level and another. The larger the gray level difference, the more main pulses are required. The same number of main pulses correspond to the same gray level difference. Driving based solely on the gray level difference to correspond to the main pulse is more efficient than existing technologies. After traversing to the main pulse based on the difference, driving can be performed according to the number of main pulses, or the main pulses can be converted into driving waveforms and stored, and then called when driving is needed. In specific embodiments, how to drive based on the main pulses also needs to be determined based on factors such as the pulse spacing and pulse width.

[0094] The present invention also provides an electrophoretic display driving method, which differs from the aforementioned embodiments in that it further includes acquiring temperature information and generating a second driving waveform lookup table based on the temperature information, the correspondence, and the difference.

[0095] In this embodiment, screen temperature needs to be considered because the viscosity of the filling liquid in the microcapsules varies under different temperature conditions. Under the same driving waveform, increased filling liquid viscosity increases the resistance to ink particle movement, resulting in insufficient movement distance of the ink particles. This can lead to the screen display being too dark or too light, affecting the display effect. Therefore, the driving waveform needs to be adjusted according to the current screen temperature to ensure that ink particles can move sufficiently to the designated position at different temperatures, achieving sufficient and accurate grayscale representation. Generally, the viscosity of the filling liquid is negatively correlated with temperature; that is, the lower the temperature, the higher the viscosity of the filling liquid.

[0096] The present invention also provides an electrophoretic display driving method, which differs from the aforementioned embodiments in that it further includes calculating a pulse direction value based on the second binary value and the first binary value; and generating a third driving waveform lookup table based on the pulse direction value, the correspondence, and the difference.

[0097] Please refer to the table below. Column P represents the pulse direction value. The reason for taking the pulse direction into account is to make it easier to know whether the drive is from white to black or from black to white, thereby further improving the driving efficiency.

[0098]

[0099] Table 2 is a LUT table based on RGB mode.

[0100] The present invention also provides an electrophoretic display driving method, which differs from the foregoing embodiments in that it further includes:

[0101] It should be noted that this embodiment addresses the main difficulties currently faced by electrophoretic displays, including but not limited to: ghosting, edge diffusion, and full refresh rate. During frontline research and development, the developers of this invention discovered that most problems with electrophoretic displays stem from the failure to properly handle the relationships between adjacent pixels on the display screen. Traditional driving methods are single-point driven and do not consider the mutual influence between electronic paper pixel particles. Because the mutual influence of neighboring particles can cause previously unchanged pixels to change, resulting in ghosting. For example, for RGBW and RGB color e-ink screens, since multiple pixels represent a single color value, the traditional method treats RGBW pixels as independent pixels, which is not the most efficient approach. This embodiment combines N*M pixels into a matrix. Based on the color value represented by the matrix and the potential mutual influence relationships between the matrix pixels, a driving waveform is generated to drive the e-ink screen. Because this model uses a matrix waveform approach, it considers the mutual influence between pixel particles, thus improving ghosting caused by pixel particle interactions; and it unifies the meaning represented by multiple pixel particles, making it more suitable for color e-ink screen driving.

[0102] The above method is illustrated below with a practical application example;

[0103] 201. Obtain the correspondence between each pixel and its display unit on the display device;

[0104] 202. Obtain the first binary value corresponding to the grayscale of any pixel in the current frame image;

[0105] 203. Obtain the second binary value corresponding to the grayscale of the pixel in the next frame image;

[0106] 204. Calculate the difference between the second binary value and the first binary value of the pixel;

[0107] Steps 201-204 are basically the same as steps 101-104, and will not be described in detail.

[0108] 205. Establish groups for a predetermined number of adjacent pixels, wherein each group contains the same number of pixels;

[0109] 206. Assign a group number to each pixel within the group;

[0110] 207. Generate a fourth drive waveform lookup table based on the group number, correspondence, and difference.

[0111] Please refer to Figure 5 In this embodiment, the M*N matrix units are prefixed with detailed information, with an encoding length of log2N bits. For example, (the RGBW sorted color e-ink screen is encoded into a 2*2 matrix, with the R component prefixed as b:00, the G component prefix as b:01, the B component prefix as b:02, and the W component prefix as b:03). The group number can be defined as binary, including: R component prefix as b:00, G component prefix as b:01, B component prefix as b:10, and W component prefix as b:11.

[0112] It should be noted that the purpose of setting the group numbers above is to ensure that the group corresponds to the filter, and the pixel corresponds to the color resistance of the filter.

[0113] In this embodiment, the application is not limited to microcapsule filters. The color particle microcapsules, microcuplets, and plasma structures are locally defined. For example, RGB can also be applied to CMYH, i.e., cyan, magenta, yellow, and white. For example, the C component is prefixed with b:00, the M component with b:01, the K component with b:10, and the W component with b:11.

[0114] For a screen that can represent n bits, i.e. 2n, a corresponding driving pulse sequence (P0, P1P2P3...Pn) is generated based on the characteristics of each component of the matrix unit to represent the old gray level to the new gray level.

[0115] The component encoding prefix is ​​superimposed on the beginning of each pulse, and the encoding is stored as an e-ink screen driver encoding table.

[0116] When refreshing the e-ink screen, the pixel component encoding of the image matrix is ​​taken. For example, for an RGB color e-ink screen, the encoding is b:00-b:11. Together with the pixel values ​​of the previous and next images, they are combined to form the waveform table index of the corresponding e-ink screen pixel.

[0117] The corresponding drive pulse is located according to the waveform table index to refresh the e-ink screen.

[0118] 208. Drive each display unit according to the fourth drive waveform lookup table;

[0119] 209. Drive the remaining display units in the group according to the fourth drive waveform lookup table.

[0120] In this embodiment, in addition to possessing the technical effects of the first embodiment, four pixels form a group, and driving any one pixel within the group also drives the other pixels in the group. When a group is processed as a color display unit, the influence between adjacent pixels is considered an internal issue within the display unit; from the perspective of each color display unit, there is no influence between display units. This effectively solves problems such as ghosting and edge blurring caused by the mutual influence of adjacent pixels.

[0121] On a 32-bit machine, it processes 4 pixels (a group) at a time, which is more than 5 times faster than existing technologies that process one pixel at a time.

[0122]

[0123] Table 4 compares the processing speed of the old and new methods.

[0124] It should be noted that the processor can traverse to the corresponding pixel's group number based on the display unit's group number, and then determine the group number. Each group is pre-assigned a group number, and all groups are stored based on these group numbers.

[0125] Please see Figure 5 In another aspect, the present invention provides an embodiment of an electrophoretic display driving device.

[0126] include:

[0127] The first acquisition unit 301 is used to acquire the correspondence between each pixel and its display unit on the display device;

[0128] The second acquisition unit 302 is used to acquire the first binary value corresponding to the gray level of any pixel in the current frame image;

[0129] The third acquisition unit 303 is used to acquire the second binary value corresponding to the gray level of the pixel in the next frame image;

[0130] In this embodiment, the first acquisition unit 301 acquires the correspondence between each pixel and its display unit on the display device; the second acquisition unit 302 acquires the first binary value corresponding to the grayscale of any pixel in the current frame image; the third acquisition unit 303 acquires the second binary value corresponding to the grayscale of the pixel in the next frame image; the three acquisition actions are not limited in order. The function of the acquisition results will be explained in subsequent embodiments.

[0131] The first calculation unit 304 is used to calculate the difference between the second binary value and the first binary value of the pixel;

[0132] In this embodiment, the first acquisition unit 301 acquires the correspondence between each pixel and its display unit on the display device;

[0133] In this embodiment, the processor executes a matching program to obtain the correspondence between each pixel and its display unit on the display device.

[0134] It should be noted that the TFT interlacing, with each intersection point being the display unit, also known in the industry as a pixel. Because this is easily confused with pixels in an image, it is represented by display units in this invention. The image needs to be displayed on the display interface of the electrophoretic display device; therefore, there is a one-to-one correspondence between image pixels and image units. The corresponding image pixels can be recorded in the memory using the coordinates of the display units, or other marking methods, which will not be elaborated upon here.

[0135] The second acquisition unit 302 acquires the first binary value corresponding to the gray level of any pixel in the current frame image;

[0136] The third acquisition unit 303 acquires the second binary value corresponding to the gray level of the pixel in the next frame image;

[0137] In this embodiment, please refer to Figure 1 This illustrates a schematic diagram of image data storage in the prior art, such as... Figure 1 As shown, SDRAM1 and SDRAM2 are used to store the image data of the previous frame and the next frame, respectively (the image data of the previous frame and the next frame can also be stored in the same SDRAM, and SDRAM1 and SDRAM2 are represented as two storage areas respectively). The image data of each pixel is stored separately, such as data1, data2, ... up to dataN. First, after powering on, the electronic paper needs to be initialized to provide a good reference value for subsequent image display. For example, after initialization, all data in SDRAM1 is set to 0, and the first frame image data is stored in SDRAM2. When displaying the first frame image, SDRAM2 is compared with SDRAM1, a lookup table is consulted, and the image is displayed. At the same time, the first frame image data (the first frame image, after being displayed, is the previous frame image relative to the second frame image to be displayed, and is also called the previous frame image data) is stored in SDRAM1. The second frame image data (the next frame image data) is stored in SDRAM2. When displaying the second frame image, SDRAM2 is compared with SDRAM1, a lookup table is consulted, and the image is displayed. SDRAM1 stores the current image. The next frame image data to be displayed is stored in SDRAM2, and so on. By repeating this process, the desired display image can be output.

[0138] In this embodiment, we first take the electrophoretic display combining microcapsules and RGB filters as an example. Color particle electrophoretic display applications can also be applied to this method embodiment. In addition to displaying black and white, the microcapsules also support grayscale display modes, such as GC4, GC8, or GC16. Here, GC represents grayscale clear refresh, and 4, 8, and 16 represent the maximum number of gray levels supported by different modes. Currently, e-ink screens can support up to 16 grayscale levels. Taking GC16 mode as an example, this mode provides 16 grayscale display effects from 0 to 15. Level 0 corresponds to white, level 15 corresponds to black, and levels 1 to 14 correspond to different gray effects that deepen sequentially from white to black. Of course, in practical applications, there are solutions that define level 0 as black and level 15 as white; this application embodiment does not limit this. When displaying various grayscale levels between black and white, the black and white ink particles are no longer driven to the top or bottom of the microcapsule, but instead move and float at a certain position within the microcapsule to correspond to the grayscale display requirements of different grayscale levels.

[0139] When displaying an image frame, the RGB image is first converted to grayscale, transforming the RGB value of each pixel into 16 grayscale levels. Then, the timing controller circuit performs a lookup table (LUT) to obtain the driving waveform for each pixel. This waveform contains information such as the current / voltage, pulse duration, and pulse period required for displaying the current frame. After receiving the driving waveforms corresponding to all pixels in the current frame, the e-paper controller drives the microcapsules corresponding to each pixel in the e-ink screen according to the driving parameters carried by the waveforms. This controls the black and white ink particles in the microcapsules to move from the current position to the next position, thereby refreshing the e-ink screen to display the next image frame.

[0140] The LUT (Low-Unit Underlying Table) is an e-ink display driver mapping table obtained and recorded by the e-ink display supplier based on screen hardware testing. This table records the driving waveform used for each pixel under different display requirements / conditions. The dependent variables typically affecting the mapping table include: the grayscale value of the pixel in the next frame, the grayscale value of the pixel in the previous frame, and the current screen temperature. The grayscale value of the pixel in the next frame determines the position the ink particles should move to, while the grayscale value of the pixel in the previous frame corresponds to the current position of the ink particles. Screen temperature needs to be considered because the viscosity of the filling liquid in the microcapsules varies under different temperature conditions. Under the same driving waveform conditions, increased filling liquid viscosity increases the resistance to ink particle movement, resulting in insufficient movement distance and causing the screen display to be too dark or too light, affecting the display effect. Therefore, the driving waveform needs to be adjusted according to the current screen temperature to ensure that ink particles can move sufficiently to the designated position at different temperatures, achieving sufficient and accurate grayscale representation. Generally, the viscosity of the filling liquid is negatively correlated with temperature; that is, the lower the temperature, the higher the viscosity of the filling liquid.

[0141] The LUT table provides all possible combinations of the three parameters: "next frame grayscale value", "previous frame grayscale value", and "current screen temperature". Each combination is mapped to a corresponding driving waveform parameter, forming the mapping table mentioned above.

[0142] During the lookup process, the timing controller circuit retrieves the grayscale image of the next frame from the system-on-chip (SOC) and obtains the grayscale value of each pixel. Then, it retrieves the grayscale image of the previous frame from the buffer, similarly obtaining the grayscale value of each pixel in the previous frame. Next, the timing controller circuit queries the SOC for temperature data around the e-ink screen. This data is monitored and transmitted to the SOC by a temperature sensor located inside the terminal and close to the back panel of the e-ink screen. After obtaining the above data, the timing controller circuit uses these three data items as dependent variables and looks up the corresponding drive waveform in the LUT table. Once the drive waveform corresponding to each pixel in a frame of image is obtained, the lookup process is complete.

[0143] The first calculation unit 304 calculates the difference between the second binary value and the first binary value of the pixel;

[0144] The establishment unit 305 is used to establish groups for a predetermined number of adjacent pixels, and each group contains the same number of pixels;

[0145] The first allocation unit 306 is used to assign a group number to each pixel within the group;

[0146] The second generation unit 307 is used to generate a fourth driving waveform lookup table based on the group number, correspondence, and difference.

[0147] The second driving unit 308 is used to drive each display unit according to the fourth driving waveform lookup table;

[0148] The third driving unit 309 is used to drive the remaining display units in the group according to the fourth driving waveform lookup table.

[0149] In this embodiment, the establishment unit 305 establishes groups for a predetermined number of adjacent pixels, and each group contains the same number of pixels;

[0150] The first allocation unit 306 assigns a group number to each pixel within the group;

[0151] The second generation unit 307 generates a fourth drive waveform lookup table based on the group number, correspondence, and difference.

[0152] Please refer to Figure 6In this embodiment, the M*N matrix units are prefixed with detailed information, with an encoding length of log2N bits. For example, (the RGBW sorted color e-ink screen is encoded into a 2*2 matrix, with the R component prefixed as b:00, the G component prefix as b:01, the B component prefix as b:02, and the W component prefix as b:03). The group number can be defined as binary, including: R component prefix as b:00, G component prefix as b:01, B component prefix as b:10, and W component prefix as b:11.

[0153] It should be noted that the purpose of setting the group numbers above is to ensure that the group corresponds to the filter, and the pixel corresponds to the color resistance of the filter.

[0154] In this embodiment, the application is not limited to microcapsule filters. The color particle microcapsules, microcuplets, and plasma structures are locally defined. For example, RGB can also be applied to CMYH, i.e., cyan, magenta, yellow, and white. For example, the C component is prefixed with b:00, the M component with b:01, the K component with b:10, and the W component with b:11.

[0155] The second driving unit 310 drives each display unit according to the fourth driving waveform lookup table;

[0156] The third driving unit 311 drives the remaining display units in the group according to the fourth driving waveform lookup table.

[0157] For a screen that can represent n bits, i.e. 2n, a corresponding driving pulse sequence (P0, P1P2P3...Pn) is generated based on the characteristics of each component of the matrix unit to represent the old gray level to the new gray level.

[0158] The component encoding prefix is ​​superimposed on the beginning of each pulse, and the encoding is stored as an e-ink screen driver encoding table.

[0159] During e-ink screen refresh, the pixel component encoding of the image matrix is ​​retrieved. For example, for an RGB color e-ink screen, the encoding is b:00-b:11. This, along with the pixel values ​​of the preceding and following images, is combined to form the waveform table index of the corresponding e-ink screen pixel. The driving pulse for the corresponding component is then located based on the waveform table index to refresh the e-ink screen.

[0160] In this embodiment, in addition to possessing the technical effects of the first embodiment, four pixels form a group, and driving any one pixel within the group also drives the other pixels in the group. When a group is processed as a color display unit, the influence between adjacent pixels is considered an internal issue within the display unit; from the perspective of each color display unit, there is no influence between display units. This effectively solves problems such as ghosting and edge blurring caused by the mutual influence of adjacent pixels.

[0161] On a 32-bit machine, it processes 4 pixels (a group) at a time, which is more than 5 times faster than existing technologies that process one pixel at a time.

[0162] The above-described device embodiments also include:

[0163] The second allocation unit is used to assign a group number to each group;

[0164] A storage unit for storing all groups according to the group number.

[0165] It should be noted that the processor can traverse to the corresponding pixel's group number based on the display unit's group number, and then determine the number within the group. The second allocation unit pre-assigns a group number to each group and stores all groups in the storage unit based on the group number.

[0166] By optimizing data processing methods, the data processing process is greatly simplified, thereby improving data processing efficiency. By changing the data storage format of waveforms, the storage space required by flash memory is reduced, thus achieving the goal of cost reduction.

[0167] In the embodiments provided in this application, it should be understood that the embodiments described herein can be implemented in hardware, software, firmware, middleware, code, or any suitable combination thereof. For hardware implementation, the processor may be implemented in one or more of the following: application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, other electronic units designed to implement the functions described herein, or combinations thereof. For software implementation, some or all of the processes of the embodiments may be performed by a computer program instructing the associated hardware. During implementation, the program may be stored in a computer-readable storage medium or transmitted as one or more instructions or code on a computer-readable storage medium. Computer-readable storage media include computer storage media and communication media, wherein communication media include any medium that facilitates the transmission of a computer program from one place to another. Storage media may be any available medium accessible to a computer. Computer-readable storage media may include, but are not limited to, RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage media or other magnetic storage devices, or any other medium capable of carrying or storing desired program code having the form of instructions or data structures and accessible to a computer.

[0168] Finally, it should be noted that the above description is only a preferred embodiment of this application and is not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for driving electrophoretic display, characterized in that, include: Obtain the correspondence between each pixel and its display unit on the display device; Get the first binary value corresponding to the gray level of any pixel in the current frame image; Obtain the second binary value corresponding to the grayscale of the pixel in the next frame image; Calculate the difference between the second binary value and the first binary value of the pixel; A first drive waveform lookup table is generated based on the correspondence and the difference; Each display unit is driven according to the first drive waveform lookup table.

2. The electrophoretic display driving method according to claim 1, characterized in that: The first drive waveform lookup table includes drive waveforms that correspond one-to-one with the differences; The number of non-zero main pulses in the driving waveform is related to the difference, and the direction corresponds to the sign of the difference.

3. The electrophoretic display driving method according to claim 2, characterized in that: The main pulse includes pulses used to drive the target grayscale error to a value of ±10 luminance units.

4. The electrophoretic display driving method according to claim 1, characterized in that: Obtain temperature information: A second drive waveform lookup table is generated based on the temperature information, the correspondence, and the difference.

5. The electrophoretic display driving method according to claim 1, characterized in that, The method includes: Calculate the pulse direction value based on the second binary value and the first binary value; A third drive waveform lookup table is generated based on the pulse direction value, the corresponding relationship, and the difference.

6. The electrophoretic display driving method according to claim 1, characterized in that, The method includes: Groups are created for a predetermined number of adjacent pixels, and each group contains the same number of pixels; Assign a group number to each pixel within the group; A fourth drive waveform lookup table is generated based on the group number, correspondence, and difference.

7. The electrophoretic display driving method according to claim 6, characterized in that, The step of creating groups for a predetermined number of adjacent pixels and assigning group numbers also includes: Assign a group number to each group; Store all groups according to the group number.

8. The electrophoretic display driving method according to claim 6, characterized in that, include: Drive each display unit according to the fourth drive waveform lookup table; The remaining display units in the group are driven according to the fourth drive waveform lookup table.

9. An electrophoretic display driving device, characterized in that, The apparatus for using the electrophoretic display driving method as described in any one of claims 1-6 comprises: The first acquisition unit is used to acquire the correspondence between each pixel and its display unit on the display device; The second acquisition unit is used to acquire the first binary value corresponding to the gray level of any pixel in the current frame image; The third acquisition unit is used to acquire the second binary value corresponding to the gray level of the pixel in the next frame image; The first calculation unit is used to calculate the difference between the second binary value and the first binary value of the pixel; The first generation unit is used to generate a first drive waveform lookup table based on the correspondence and the difference; The first driving unit is used to drive each display unit according to the first driving waveform lookup table.

10. The electrophoretic display driving device according to claim 9, characterized in that, The device includes: A grouping unit is used to create groups of a predetermined number of adjacent pixels, wherein each group contains the same number of pixels; The first allocation unit is used to assign a group number to each pixel within the group; The second generation unit is used to generate a fourth driving waveform lookup table based on the group number, correspondence, and difference.

11. The electrophoretic display driving method according to claim 9, characterized in that, The device includes: The second allocation unit is used to assign a group number to each group; A storage unit for storing all groups according to the group number.

12. The electrophoretic display driving method according to claim 9, characterized in that, include: The second driving unit is used to drive each display unit according to the fourth driving waveform lookup table; The third driving unit is used to drive the remaining display units in the group according to the fourth driving waveform lookup table.

Images