Bistable display and method for driving bistable display

Abstract

A bistable display comprises a display panel and a drive apparatus, wherein the display panel comprises a plurality of pixels, a plurality of scan lines and a plurality of data lines; and the drive apparatus transmits scan signals and data signals to the scan lines and the data lines, respectively, and provides a common voltage to the pixels, such that the pixels are controlled to be in a bright state, a fully bright state, or a fully dark state, the pixels having a first reflectance in the bright state and a second reflectance in the fully bright state, respectively, and the first reflectance being less than the second reflectance.

Description

Bistable Display and Bistable Display Driving Method Technical Field

[0001] This disclosure relates to a display and a display driving method, and more particularly to a bistable display and a bistable display driving method. Background Technology

[0002] Existing cholesteric liquid crystal displays (ChLCDs) can only display static images and cannot display dynamic images. Furthermore, most existing cholesteric liquid crystal displays are passive displays, thus unable to achieve the goal of animation display. Moreover, cholesteric liquid crystals generally have high viscosity, resulting in high liquid crystal driving voltage, long liquid crystal driving time, and long liquid crystal response time.

[0003] Cholesterol liquid crystals can remain in a stable planar state or a focal conic state after being driven. For a display to support animation playback, a short drive time is necessary. However, insufficient drive time for cholesterol liquid crystals affects the brightness and contrast of the image, while the long response time of the liquid crystal cannot meet the requirements of animation display. Therefore, developers face a dilemma: pursuing short drive times while maintaining good brightness and contrast. Summary of the Invention

[0004] Therefore, the purpose of this disclosure is to provide a bistable display and a bistable display driving method, which controls the pixels to switch between a bright state, a fully bright state and a fully dark state through a driving device, and controls the pixels to remain in the bright state during the process of switching from the fully dark state to the fully bright state, using the first reflectivity in the bright state as the application of dynamic display, so as to achieve the goal of fast response and realize animation display.

[0005] According to one embodiment of this disclosure, a bistable display is provided, comprising a display panel and a driving device. The display panel includes a plurality of pixels, a plurality of scan lines, and a plurality of data lines. The driving device is coupled to the display panel. The driving device transmits a plurality of scan signals to the plurality of scan lines and a plurality of data signals to the plurality of data lines, and provides a common voltage to the plurality of pixels. The driving device controls the plurality of pixels to be in a bright state, a fully bright state, or a fully dark state according to the plurality of scan signals, the plurality of data signals, and the common voltage. When the common voltage has an opposite phase to one of the plurality of data signals, one of the plurality of pixels connected to that data signal is in a fully dark state. When the common voltage has the same phase as that data signal, that pixel is in a bright state or a fully bright state. The pixel in the bright state and the fully bright state respectively has a first reflectivity and a second reflectivity, and the first reflectivity is less than the second reflectivity.

[0006] Other embodiments of the foregoing implementation are as follows: The aforementioned driving device includes a gate driver, a source driver, and a common electrode driving unit. The gate driver is electrically connected to the plurality of scan lines and is used to generate the plurality of scan signals. The source driver is electrically connected to the plurality of data lines and is used to generate the plurality of data signals. The common electrode driving unit is electrically connected to the plurality of pixels and is used to generate a common voltage.

[0007] Other embodiments of the aforementioned implementation are as follows: the aforementioned first reflectivity is between 50% and 70% of the second reflectivity.

[0008] Other embodiments of the aforementioned implementation are as follows: The aforementioned driving device transmits one of the plurality of scan signals having a high level to scan the plurality of pixels, and transmits a common voltage with opposite phase and the plurality of data signals, so that the plurality of pixels switch from a completely bright state to a completely dark state after a first response time. The driving device transmits one of the plurality of scan signals having a high level to scan the plurality of pixels, and transmits a common voltage with the same phase and the plurality of data signals, so that the plurality of pixels switch from a completely dark state to a bright state after a second response time. The driving device transmits one of the plurality of scan signals having a high level to scan the plurality of pixels, and transmits a common voltage with the same phase and the plurality of data signals, so that the plurality of pixels switch from a completely dark state to a completely bright state after a third response time. The first response time is shorter than the second response time, and the second response time is shorter than the third response time.

[0009] Other embodiments of the aforementioned implementation are as follows: The aforementioned driving device executes a color mixing display program. The color mixing display program controls at least one of the plurality of pixels to be in a fully bright state and controls at least another of the plurality of pixels to be in a fully dark state according to a lookup table, so that the plurality of pixels present a grayscale image.

[0010] Other embodiments of the aforementioned implementation are as follows: The aforementioned driving device divides the plurality of data signals within a scanning time into at least one part having an opposite phase to the common voltage and another at least one part having the same phase as the common voltage, thereby controlling the plurality of pixels to be in a grayscale state.

[0011] Other embodiments of the aforementioned implementation are as follows: The aforementioned display panel has a dynamic display area and a static display area. The driving device acquires dynamic image data corresponding to the dynamic display area, and transmits a portion of the plurality of scan signals having a high level to a portion of the plurality of scan lines corresponding to the dynamic display area according to the dynamic image data, so as to update a frame of image presented by a portion of the plurality of pixels located in the dynamic display area. The driving device acquires static image data corresponding to the static display area, and transmits another portion of the plurality of scan signals having a low level to another portion of the plurality of scan lines corresponding to the static display area according to the static image data, so as to maintain another frame of image presented by another portion of the plurality of pixels located in the static display area.

[0012] Other embodiments of the aforementioned implementation are as follows: The aforementioned display panel is a cholesterol liquid crystal display panel.

[0013] According to another embodiment of this disclosure, a bistable display driving method is provided for driving a bistable display. The bistable display includes a display panel and a driving device. The display panel includes a plurality of pixels, a plurality of scan lines, and a plurality of data lines. The bistable display driving method includes transmitting a plurality of scan signals to the plurality of scan lines via the driving device; transmitting a plurality of data signals to the plurality of data lines via the driving device and providing a common voltage to the plurality of pixels; and controlling the plurality of pixels to be in a bright state, a fully bright state, or a fully dark state via the driving device based on the plurality of scan signals, the plurality of data signals, and the common voltage. Wherein, when the common voltage has an opposite phase to one of the plurality of data signals, one of the plurality of pixels connected to that data signal is in a fully dark state. Wherein, when the common voltage has the same phase as that data signal, that pixel is in a bright state or a fully bright state. Wherein, the pixel in the bright state and the fully bright state has a first reflectivity and a second reflectivity, respectively, and the first reflectivity is less than the second reflectivity.

[0014] Other embodiments of the aforementioned implementation are as follows: the aforementioned first reflectivity is between 50% and 70% of the second reflectivity.

[0015] Other embodiments of the aforementioned implementation are as follows: The aforementioned step of controlling the plurality of pixels to be in a bright state, a fully bright state, or a fully dark state further includes: transmitting one of the plurality of scan signals having a high level through a driving device to scan the plurality of pixels, and transmitting a common voltage with opposite phase and the plurality of data signals, so that the plurality of pixels switch from a fully bright state to a fully dark state after a first response time; transmitting one of the plurality of scan signals having a high level through a driving device to scan the plurality of pixels, and transmitting a common voltage with the same phase and the plurality of data signals, so that the plurality of pixels switch from a fully dark state to a bright state after a second response time; and transmitting one of the plurality of scan signals having a high level through a driving device to scan the plurality of pixels, and transmitting a common voltage with the same phase and the plurality of data signals, so that the plurality of pixels switch from a fully dark state to a fully bright state after a third response time. The first response time is shorter than the second response time, and the second response time is shorter than the third response time.

[0016] Other embodiments of the foregoing implementation are as follows: The aforementioned step of controlling the plurality of pixels to be in a bright state, a fully bright state, or a fully dark state further includes executing a color mixing display program through a driving device. The color mixing display program controls at least one of the plurality of pixels to be in a fully bright state and controls at least another of the plurality of pixels to be in a fully dark state according to a lookup table, so that the plurality of pixels present a grayscale image.

[0017] Other embodiments of the aforementioned implementation are as follows: The aforementioned driving device divides the plurality of data signals within a scanning time into at least one part having an opposite phase to the common voltage and another at least one part having the same phase as the common voltage, thereby controlling the plurality of pixels to be in a grayscale state.

[0018] Other embodiments of the aforementioned implementation are as follows: The aforementioned display panel has a dynamic display area and a static display area. The driving method of the bistable display further includes obtaining dynamic image data corresponding to the dynamic display area through a driving device, and transmitting a portion of the plurality of scan signals having a high level to a portion of the plurality of scan lines corresponding to the dynamic display area according to the dynamic image data transmission, so as to update a frame of image presented by a portion of the plurality of pixels located in the dynamic display area; and obtaining static image data corresponding to the static display area through a driving device, and transmitting another portion of the plurality of scan signals having a low level to another portion of the plurality of scan lines corresponding to the static display area according to the static image data transmission, so as to maintain another frame of image presented by another portion of the plurality of pixels located in the static display area.

[0019] Other embodiments of the aforementioned implementation are as follows: The aforementioned display panel is a cholesterol liquid crystal display panel. Attached Figure Description

[0020] Figure 1 is a schematic diagram illustrating a bistable display according to a first embodiment of the present disclosure;

[0021] Figure 2 is a schematic diagram illustrating a bistable display driving method according to a second embodiment of the present disclosure;

[0022] Figure 3 is a timing diagram showing the scan signal, data signal and common voltage of the bistable display in Figure 1 at different pixel stages;

[0023] Figure 4 is a reflectance-time response diagram of a pixel in the bistable display of Figure 1;

[0024] Figure 5 is a schematic diagram showing the 2x2 grayscale display combination of the bistable display of Figure 1;

[0025] Figure 6 is another timing diagram showing the scan signal, data signal, and common voltage of the bistable display of Figure 1 at different pixel stages; and

[0026] Figure 7 is a schematic diagram showing the dynamic display area and static display area of ​​the bistable display in Figure 1.

[0027] Explanation of reference numerals in the attached figures: 100: Bistable display; 110: Display panel; 120: Driving device; 121: Gate driver; 122: Source driver; 123: Common electrode driving unit; 124: Timing controller; 200: Bistable display driving method; A1, A2, A3, A4, A5: Display area; DA: Dynamic display area; D1, D2, D5, D6, D7, D8, D9, D M-1 D M Data cables DS, DS1, DS2, DSM-1 DS M Data signals G1, G2, G4, G5, G6, G7, G8, G9, G N Scan lines GS, GS1, GS2, GS N Scan signal Ena: Enable signal Hsync: Horizontal synchronization signal P: Pixels PP1, PP2, PP3, PP4, PP5, PP6, PP7: Pixel duration RT1: First response time RT2: Second response time RT3: Third response time S01, S02, S03: Steps SA: Static display area SB: Bright state SEB: Fully bright state SED: Fully dark state T: Transistor Vcom: Common voltage Vdiff: Voltage difference Detailed Implementation

[0028] Several embodiments of this disclosure will be described below with reference to the accompanying drawings. For clarity, many practical details will be set forth in the following description. However, it should be understood that these practical details should not be used to limit the scope of this disclosure. That is, in some embodiments of this disclosure, these practical details are not essential. Furthermore, for the sake of simplicity in the drawings, some conventionally used structures and elements will be shown in a simple schematic manner; and repeated elements may be denoted by the same reference numerals.

[0029] Furthermore, in this document, when a component (or unit or module, etc.) is "connected / linked" to another component, it can mean that the component is directly connected / linked to the other component, or it can mean that the component is indirectly connected / linked to the other component, that is, there is another component between the component and the other component. Only when it is explicitly stated that a component is "directly connected / linked" to another component does it mean that there is no other component between the component and the other component. The terms "first," "second," and "third" are only used to describe different components and do not limit the components themselves; therefore, "first component" can also be referred to as "second component." Moreover, the combinations of components / units / circuits in this document are not combinations generally known, conventional, or existing in this field. Whether the component / unit / circuit itself is existing cannot be used to determine whether its combination relationship is easily accomplished by someone of ordinary skill in the art.

[0030] Please refer to FIG1, which is a schematic diagram illustrating a bistable display according to a first embodiment of the present disclosure. As shown in FIG1, the bistable display 100 includes a display panel 110 and a driving device 120.

[0031] The display panel 110 includes a pixel array composed of multiple pixels P and multiple scan lines G1 to G2. N and multiple data lines D1 to D M Scan lines G1 to GN The numbers from top to bottom in Figure 1 are G1, G2, ... G N Data cables D1~D M The numbers from left to right in Figure 1 are D1, D2, ... D M-1 D M The drive unit 120 is coupled to the display panel 110 and transmits multiple scan signals GS1 to GS1. N To the plurality of scan lines G1 to G N And transmits multiple data signals DS1 to DS2 M To the multiple data lines D1 to D M The driving device 120 provides a common voltage Vcom to the plurality of pixels P. The driving device 120 operates according to the plurality of scan signals GS1 to GS2. N The plurality of data signals DS1 to DS2 M The common voltage Vcom controls the multiple pixels P to be in a bright state, a fully bright state, or a fully dark state.

[0032] When the common voltage Vcom is related to the plurality of data signals DS1~DS M When one of them has an opposite phase, the multiple data signals DS1 to DS2 are connected. M One of the plurality of pixels P is in a completely dark state. When the common voltage Vcom is equal to the plurality of data signals DS1 to DS2... M When these pixels have the same phase, these pixels P are either in a bright state or a fully bright state. These pixels P have a first reflectivity and a second reflectivity in the bright and fully bright states, respectively, with the first reflectivity being less than the second reflectivity. Therefore, the bistable display 100 of this disclosure can control the pixels P in the display panel 110 to switch between a bright state, a fully bright state, and a fully dark state via the driving device 120. Specifically, during the transition from a fully dark state to a fully bright state, the driving device 120 controls pixel P to remain in the bright state, and uses the first reflectivity of pixel P in the bright state for dynamic display, enabling the bistable display 100 to achieve a fast response and realize animated display while maintaining the brightness and darkness of the image.

[0033] In some embodiments, the bistable display 100 may be, but is not limited to, an active-matrix cholesteric liquid crystal display (ChLCD), and the display panel 110 may be, but is not limited to, a cholesteric liquid crystal display panel. Each pixel P in the pixel array contains cholesteric liquid crystal, and it can be simplified to a circuit composed of a transistor T, a storage capacitor, and a liquid crystal capacitor. The transistor T may be a switching element, such as a thin-film transistor (TFT).

[0034] In some embodiments, the driving device 120 may include a gate driver 121, a source driver 122, and a common electrode driving unit 123. The gate driver 121 is electrically connected to scan lines G1 to G2. N And used to generate scan signals GS1~GS N Source driver 122 is electrically connected to data lines D1 to D2. M And used to generate data signals DS1 to DS2 M The common electrode driving unit 123 is electrically connected to the pixel P in the display panel 110 and is used to generate a common voltage Vcom.

[0035] In some embodiments, the driving device 120 may further include a timing controller 124. The timing controller 124 is electrically connected to the gate driver 121, the source driver 122, and the common electrode driving unit 123. The timing controller 124 transmits an enable signal Ena to the gate driver 121, thereby controlling the gate driver 121 to generate scan signals GS1 to GS1. N The timing controller 124 transmits a horizontal synchronization signal Hsync to the source driver 122, thereby controlling the source driver 122 to generate data signals DS1 to DS22. M The common electrode driving unit 123 generates a common voltage Vcom based on the pixel driving information obtained by the timing controller 124, and provides the common voltage Vcom to the common electrode of the display panel 110.

[0036] Please refer to Figures 1, 2, 3, and 4 together. Figure 2 is a schematic diagram illustrating a bistable display driving method according to a second embodiment of this disclosure. Figure 3 is a timing diagram showing the scan signal, data signal, and common voltage of the bistable display of Figure 1 at different pixel stages. Figure 4 is a reflectivity-time response diagram of the pixels in the bistable display of Figure 1. As shown in Figure 2, the bistable display driving method 200 is used to drive the bistable display 100 to display a screen and includes the following steps S01, S02, and S03.

[0037] Step S01 involves transmitting multiple scan signals GS1 to GS1 through the gate driver 121 of the driving device 120. N Up to multiple scan lines G1~G N .

[0038] Step S02 involves transmitting multiple data signals DS1 to DS2 through the source driver 122 of the drive device 120. M To multiple data lines D1~D M It also provides a common voltage Vcom to multiple pixels P.

[0039] Step S03 involves using the driving device 120 to scan the plurality of scanning signals GS1 to GS1. N The plurality of data signals DS1 to DS2 M The common voltage Vcom controls the multiple pixels P to be in a bright state SB, a fully bright state SEB, or a fully dark state SED. The bright state SB can be a transient state in cholesteric liquid crystal, while the fully bright state SEB and the fully dark state SED can be bistable states in cholesteric liquid crystal. In other words, the bright state SB is the homeotropic state in cholesteric liquid crystal, while the fully bright state SEB and the fully dark state SED are the planar state and focal conic state, respectively, in cholesteric liquid crystal.

[0040] As shown in Figures 3 and 4, the scanning signal GS consists of each scanning signal GS1 to GS2. N The collective term for data signals DS, which refers to the various data signals DS1 to DS2. M The voltage difference Vdiff is the voltage difference between the data signal DS and the common voltage Vcom. The transistor T in pixel P is turned on by the corresponding scan signal GS to perform a decision scan. During the determining phase, pixel P is driven by the corresponding data signal DS and the common voltage Vcom according to the image to be displayed by the user, thereby being in the bright state SB, the fully bright state SEB, or the fully dark state SED, so that the pixel array displays the image.

[0041] In detail, these three states can be switched by the electric field (i.e., voltage difference Vdiff) applied to pixel P. For example, when pixel P is in the fully bright state SEB (planar state) displaying a white image, if a smaller electric field is applied, pixel P can switch from the fully bright state SEB to the fully dark state SED (focal cone state) and display a black image; if a higher electric field is applied and maintained, pixel P switches to the bright state SB (vertical state). In particular, when pixel P is in the bright state SB, if the electric field is quickly removed, pixel P returns to the fully bright state SEB; if the electric field is slowly removed, pixel P returns to the fully dark state SED. Therefore, the state of cholesteric liquid crystal can be changed by the speed of electric field removal.

[0042] In some embodiments, the gate driver 121 of the driving device 120 transmits a scan signal GS with a high level (V+) during pixel period PP1 to scan pixel P. The common electrode driving unit 123 and the source driver 122 of the driving device 120 transmit a common voltage Vcom and a data signal DS with opposite phases, respectively. The common voltage Vcom is high level (V+), and the data signal DS is low level (V-), so that pixel P can switch from the fully bright state SEB to the fully dark state SED after a first response time RT1, which is equivalent to a dark positive frame.

[0043] In some embodiments, the gate driver 121 of the driving device 120 transmits a high-level (V+) scan signal GS during pixel period PP2, and transmits a common voltage Vcom and a data signal DS with opposite phases, respectively. Unlike pixel period PP1, the common voltage Vcom in pixel period PP2 is low-level (V-), the data signal DS is high-level (V+), and pixel P also switches from the fully bright state SEB to the fully dark state SED after a first response time RT1, which is equivalent to a dark negative frame.

[0044] In some embodiments, the gate driver 121 of the driving device 120 transmits a high-level scan signal GS during pixel period PP3 to scan pixel P. The common electrode driving unit 123 and the source driver 122 of the driving device 120 transmit a common voltage Vcom and a data signal DS with the same phase, respectively. Both the common voltage Vcom and the data signal DS are high (V+), so that pixel P can switch from the completely dark state SED to the bright state SB after a second response time RT2, which is equivalent to a bright positive frame.

[0045] In some embodiments, the gate driver 121 of the driving device 120 transmits a high-level scan signal GS during pixel period PP4 to scan pixel P. The common electrode driving unit 123 and the source driver 122 of the driving device 120 transmit a common voltage Vcom and a data signal DS with the same phase, respectively. Unlike pixel period PP3, both the common voltage Vcom and the data signal DS are low-level (V-) during pixel period PP4, and pixel P needs to switch from the completely dark state SED to the completely bright state SEB after a third response time RT3, which is equivalent to a bright negative frame.

[0046] Specifically, the first response time RT1 is shorter than the second response time RT2, and the second response time RT2 is shorter than the third response time RT3. To achieve fast response in the bistable display 100 of this disclosure, the first reflectivity of pixel P in the bright state SB is between 50% and 70% of the second reflectivity of pixel P in the fully bright state SEB. It should be noted that the fast response time mainly utilizes the non-steady-state characteristics of cholesteric liquid crystal. Applying a large voltage causes the cholesteric liquid crystal to be in a vertical state, at which point the cholesteric liquid crystal reflects a focal conic state. If the large voltage is released, the cholesteric liquid crystal switches back to a planar state. However, a complete switch back to a planar state takes a long time.

[0047] Therefore, the second reflectivity of pixel P controlled by the driving device 120 in the fully bright state SEB (50%–70%) can be applied to the screen display. Since the screen update is performed in the vertical state, no additional high voltage is required for screen reset before the screen is displayed. At this time, pixel P is in the bright state SB, and the driving device 120 then closes the scan line and starts the next scan line. The first response time RT1 for switching from the fully bright state SEB to the fully dark state SED is less than 5 milliseconds (ms), and the second response time RT2 for switching from the fully dark state SED to the bright state SB is less than 10 ms, which fully meets the requirements for animation display (i.e., the human eye's visual requirement is less than 17 ms).

[0048] Please refer to Figure 5, which is a schematic diagram showing the 2x2 grayscale display combination of the bistable display of Figure 1. As shown in Figure 5, the driving device 120 can execute a color mixing display program. The color mixing display program controls at least one pixel P to be in a fully bright state (SEB) and controls at least another pixel P to be in a fully dark state (SED) according to a lookup table, so that the aforementioned at least one pixel P and the other at least one pixel P display a grayscale image. The lookup table can be pre-stored in the timing controller 124 of the driving device 120, or provided via an external controller (not shown), and the lookup table can list the image control information corresponding to each pixel P.

[0049] The pixel array of the display panel 110 can be divided into multiple display areas A1, A2, A3, A4, and A5. Display areas A1, A2, A3, A4, and A5 can be composed of multiple pixels P (2x2 pixels) from different areas of the pixel array. The driving device 120 executes a color mixing display program, controlling display area A1 to display a white image using a checkerboard color mixing method (Dithering), controlling display areas A2, A3, and A4 to display grayscale images with different grayscale values, and controlling display area A5 to display a black image. While general monitors can only display eight colors (WKRGBCMY) for animation, the display panel 110 disclosed herein can be constructed from three layers of R / G / B cholesteric liquid crystal stacked together. The checkerboard color mixing method exceeds the spatial visual resolution limit of the human eye; therefore, the driving device 120 can control the display panel 110 to display full grayscale color animation using the color mixing display program.

[0050] Please refer to Figure 6, which is another timing diagram showing the scan signal, data signal and common voltage of the bistable display of Figure 1 at different pixel stages.

[0051] As shown in Figure 6, in some embodiments, the driving device 120 can divide the data signal DS during the scanning time into four equal parts with the same phase as the common voltage Vcom during the pixel period PP5, thereby controlling the pixel P to be in a fully bright state SEB. In some embodiments, the driving device 120 can divide the data signal DS during the scanning time into two equal parts with the same phase as the common voltage Vcom and another two equal parts with the opposite phase to the common voltage Vcom during the pixel period PP6, thereby controlling the pixel P to be in a grayscale state. In detail, the input of different waveforms when the gate of transistor T is turned on can determine the change in the brightness of pixel P. In other words, when a signal that is not completely black or not completely white is input in the grayscale state, the human eye can perceive the change in black and white grayscale based on the effect of visual persistence, thereby achieving the goal of full-color display. In some embodiments, the driving device 120 can divide the data signal DS during the scanning time into four equal parts with the opposite phase to the common voltage Vcom during the pixel period PP7, thereby controlling the pixel P to be in a fully dark state SED.

[0052] Therefore, the bistable display 100 disclosed herein can achieve full grayscale color display not only by using a color mixing display program, but also by dividing the data signal DS into multiple equal parts and adjusting the input duration or the high and low level voltages corresponding to different parts, thus achieving the function of full grayscale display.

[0053] Please refer to Figure 7, which is a schematic diagram showing the dynamic display area and static display area of ​​the bistable display of Figure 1. As shown in Figure 7, the display panel 110 may have a dynamic display area DA and a static display area SA. The driving device 120 obtains dynamic image data corresponding to the dynamic display area DA and static image data corresponding to the static display area SA from an external controller.

[0054] In some embodiments, the driving device 120 can transmit high-level scan signals GS4 to GS9 to scan lines G4 to G9 corresponding to the dynamic display area DA according to the dynamic image data, so as to turn on the corresponding transistors T one by one and update the frame image presented by the pixel P located in the dynamic display area DA. Furthermore, the driving device 120 can transmit low-level scan signals (scan signals other than scan signals GS4 to GS9) to scan lines (scan lines other than scan lines G4 to G9) corresponding to the static display area SA according to the static image data, so as to maintain another frame image presented by the pixel P located in the static display area SA. Specifically, the driving device 120 can select any area on the display panel 110 to dynamically display an image or maintain the previously displayed image according to the dynamic image data and the static image data. For example, the dynamic display area DA can be configured to dynamically display an image, and the static display area SA can be configured to maintain the previously displayed image.

[0055] Furthermore, the dynamic / static switching display can be divided into full-screen switching and area-screen switching. In full-screen switching, the driving device 120 only needs to increase the scanning cycle and scanning time to improve contrast and reflectivity, and switch the dynamic image to a static image. Conversely, to switch from a static image to a dynamic image, it is only necessary to switch to the second reflectivity under the full brightness state SEB of approximately 50% to 70% to apply it to the dynamic image display. In area-screen switching, the full screen can consist of a static state and an animated state. The driving device 120 only needs to independently drive the scan lines G4 to G9 and data lines D5 to D9 corresponding to the dynamic display area DA. The remaining static image (i.e., the static display area SA) remains static because it is not driven.

[0056] In summary, the bistable display and its driving method disclosed herein have the following advantages: First, by switching approximately 50% to 70% of the reflectivity in the planar state, the problem of rapid response can be solved, achieving the goal of animated display and thus meeting the application needs of different products. Second, by utilizing color mixing or signal segmentation methods, the display panel can have the function of displaying full grayscale color animation. Third, by independently driving the scan lines and data lines corresponding to the dynamic display area, the display panel can have the function of switching between dynamic and static images.

[0057] Although the present disclosure has been described above with reference to embodiments, it is not intended to limit the present disclosure. Any person skilled in the art may make various changes and modifications without departing from the concept and scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be determined by the claims.

Claims

1. A bistable display, characterized by The display panel comprises: a plurality of pixels; a plurality of scan lines connected to the plurality of pixels; and a plurality of data lines connected to the plurality of pixels; and a driving device coupled to the display panel, the driving device transmitting a plurality of scan signals to the plurality of scan lines and a plurality of data signals to the plurality of data lines, and providing a common voltage to the plurality of pixels, wherein the driving device controls the plurality of pixels to be in a bright state, a full bright state or a full dark state according to the plurality of scan signals, the plurality of data signals and the common voltage; wherein one of the plurality of pixels connected to the one of the plurality of data signals is in the full dark state when the common voltage and the one of the plurality of data signals have opposite phases; wherein the one of the plurality of pixels is in the bright state or the full bright state when the common voltage and the one of the plurality of data signals have the same phase; wherein the one of the plurality of pixels has a first reflectivity and a second reflectivity in the bright state and the full bright state respectively, and the first reflectivity is less than the second reflectivity. The driving device comprises:

2. The bistable display of claim 1, wherein, a gate driver electrically connected to the plurality of scan lines and configured to generate the plurality of scan signals; a source driver electrically connected to the plurality of data lines and configured to generate the plurality of data signals; and a common electrode driving unit electrically connected to the plurality of pixels and configured to generate the common voltage. The first reflectivity is between 50% and 70% of the second reflectivity.

4. The bistable display of claim 1, wherein:

3. The bi-stable display of claim 1, wherein, the driving device transmits the one of the plurality of scan signals having a high level to scan the one of the plurality of pixels, and transmits the common voltage and the one of the plurality of data signals having opposite phases to switch the one of the plurality of pixels from the full bright state to the full dark state through a first response time; the driving device transmits the one of the plurality of scan signals having the high level to scan the one of the plurality of pixels, and transmits the common voltage and the one of the plurality of data signals having the same phase to switch the one of the plurality of pixels from the full dark state to the bright state through a second response time; and the driving device transmits the one of the plurality of scan signals having the high level to scan the one of the plurality of pixels, and transmits the common voltage and the one of the plurality of data signals having the same phase to switch the one of the plurality of pixels from the full dark state to the full bright state through a third response time; wherein the first response time is less than the second response time, and the second response time is less than the third response time. The driving device performs a color mixing display procedure, the color mixing display procedure controls at least one of the plurality of pixels to be in the full bright state and another at least one of the plurality of pixels to be in the full dark state according to a lookup table, so that the plurality of pixels presents a gray scale picture. ​ ​ 5. The bi-stable display of claim 1, wherein, ​ 6. The bi-stable display of claim 1, wherein, The driving device divides the one of the plurality of data signals in a scanning time into at least one portion having opposite phase with the common voltage and another at least one portion having same phase with the common voltage, thereby controlling the one of the plurality of pixels to be in a gray scale state.

7. The bistable display of claim 1, wherein, The display panel has a dynamic display area and a static display area; The driving device obtains a dynamic picture data corresponding to the dynamic display area, and transmits a portion of the plurality of scanning signals having a high level to a portion of the plurality of scanning lines corresponding to the dynamic display area according to the dynamic picture data, so as to update a frame of picture presented by a portion of the plurality of pixels located in the dynamic display area; and The driving device obtains a static picture data corresponding to the static display area, and transmits another portion of the plurality of scanning signals having a low level to another portion of the plurality of scanning lines corresponding to the static display area according to the static picture data, so as to maintain another frame of picture presented by another portion of the plurality of pixels located in the static display area.

8. The bi-stable display of claim 1, wherein, The display panel is a cholesteric liquid crystal display panel.

9. A method for driving a bistable display, the bistable display comprising a display panel and a driving device, the display panel comprising a plurality of pixels, a plurality of scan lines and a plurality of data lines, the method comprising: The driving method of the bistable display comprises: transmitting, by the driving device, a plurality of scanning signals to the plurality of scanning lines; transmitting, by the driving device, a plurality of data signals to the plurality of data lines, and providing a common voltage to the plurality of pixels; and controlling, by the driving device, the plurality of pixels to be in a bright state, a full bright state or a full dark state according to the plurality of scanning signals, the plurality of data signals and the common voltage; wherein, when the common voltage has opposite phase with one of the plurality of data signals, one of the plurality of pixels connected to the one of the plurality of data signals is in the full dark state; wherein, when the common voltage has same phase with the one of the plurality of data signals, the one of the plurality of pixels is in the bright state or the full bright state; wherein, the one of the plurality of pixels has a first reflectivity and a second reflectivity in the bright state and the full bright state respectively, and the first reflectivity is less than the second reflectivity.

10. The method of claim 9, wherein the display is a bistable display. The first reflectivity is between 50% and 70% of the second reflectivity.

11. The method of claim 9, wherein the method further comprises: determining whether the display is in the first or second state; and applying the first or second voltage to the display based on the determination. 5 The step of controlling the plurality of pixels to be in the bright state, the full bright state or the full dark state further comprises: transmitting, by the driving device, one of the plurality of scanning signals having a high level to scan the one of the plurality of pixels, and transmitting the common voltage having opposite phase and the one of the plurality of data signals to make the one of the plurality of pixels switch from the full bright state to the full dark state through a first response time; transmitting, by the driving device, the one of the plurality of scanning signals having the high level to scan the one of the plurality of pixels, and transmitting the common voltage having same phase and the one of the plurality of data signals to make the one of the plurality of pixels switch from the full dark state to the bright state through a second response time; and and The driving device transmits the one of the plurality of scanning signals having the high level to scan the one of the plurality of pixels, and transmits the common voltage having the same phase and the one of the plurality of data signals to switch the one of the plurality of pixels from the fully dark state to the fully bright state through a third response time. The first response time is less than the second response time, and the second response time is less than the third response time.

12. The method of claim 9, wherein the display is a bistable display. The step of controlling the plurality of pixels to be in the bright state, the fully bright state or the fully dark state further comprises: The driving device performs a color mixing display procedure according to a look-up table to control at least one of the plurality of pixels to be in the fully bright state and another at least one of the plurality of pixels to be in the fully dark state, so that the plurality of pixels presents a gray scale picture.

13. The method of claim 9, wherein the method further comprises: determining a first display state of the bistable display; and determining a second display state of the bistable display. The driving device divides the one of the plurality of data signals in a scanning time into at least one portion having opposite phase with the common voltage and another at least one portion having the same phase with the common voltage, thereby controlling the one of the plurality of pixels to be in a gray scale state.

14. The method of claim 9, wherein the method further comprises: determining a first display state of the bistable display; and determining a second display state of the bistable display. The display panel has a dynamic display area and a static display area, and the driving method of the bistable display further comprises: The driving device obtains a dynamic picture data corresponding to the dynamic display area, and transmits a part of the plurality of scanning signals having a high level to a part of the plurality of scanning lines corresponding to the dynamic display area according to the dynamic picture data, so as to update a frame picture presented by a part of the plurality of pixels located in the dynamic display area; and The driving device obtains a static picture data corresponding to the static display area, and transmits another part of the plurality of scanning signals having a low level to another part of the plurality of scanning lines corresponding to the static display area according to the static picture data, so as to maintain another frame picture presented by another part of the plurality of pixels located in the static display area.

15. The method of claim 9, wherein the method further comprises: determining whether the display is in the first or second state; and applying a voltage to the display to change the state of the display. 15 The display panel is a cholesteric liquid crystal display panel.

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