Display panel, method for displaying image, and display apparatus

Abstract

The embodiment of the invention provides a display panel. The display panel comprises a plurality of pixel units. At least one pixel unit is composed of two sub-pixels, and the colors of the two sub-pixels of each pixel unit in the at least one pixel unit are in a complementary color relation. Each of the at least one pixel unit may be configured to generate a white point when the two sub-pixels are set together in a first state and generate a black point when the two sub-pixels are set together in a second state. The plurality of pixel units may include a plurality of first pixel units and a plurality of second pixel units arranged alternately. The two sub-pixels of each of the first pixel units may have a first pair of colors in a complementary color relationship, and the two sub-pixels of each of the second pixel units may have a second pair of colors in a complementary color relationship.

Description

Technical Field

[0001] The present application generally relates to a display device, and more particularly to a display panel, wherein each pixel unit includes a sub-pixel. Background Art

[0002] Electronic book products using reflective displays, such as electronic paper displays (EPD) or liquid crystal displays (LCD) are widely used. However, in general, the brightness and color gamut (or color reproducibility) of existing products are very poor compared to books printed on paper. Due to the display structure and mechanism, the characteristics of brightness and color gamut are in a trade-off relationship. For example, the image quality of monochrome or black-and-white (B / W) electronic book products is getting closer to newspapers, but is still lower than that of gravure-printed magazines using glossy paper.

[0003] Existing display devices traditionally use the RGB three primary colors additive color mixing theory to produce full color, that is, each pixel consists of red (R), green (G) and blue (B) sub-pixels. It should be noted that this can be applied not only to non-emissive displays (e.g., reflective or transmissive using backlight), such as EPD and LCD, but also to emissive displays, such as organic light emitting diode (OLED) displays and light emitting diode (LED) displays. The RGB colors in some displays (including reflective displays) are achieved through color filters, which can determine the achievable color gamut and reduce the brightness due to their limited transmittance.

[0004] A known solution to improve the trade-off between brightness and color gamut is to add a white (W) sub-pixel to each RGB pixel (i.e., a pixel with R, G, and B sub-pixels) to form an RGBW pixel. By adding a W sub-pixel without a color filter, the brightness can be increased, while the color gamut determined by the three primary colors of RGB is substantially the same. However, this known solution reduces the size of each sub-pixel by 3 / 4 times, thereby reducing the brightness of each color component. Therefore, it cannot increase the overall brightness to the expected extent. In addition, since a sub-pixel circuit including a thin film transistor (TFT) and a capacitor needs to be provided, there are limitations in reducing the size of the sub-pixel. Therefore, there are limitations in pixel size and resolution. For RGBW pixels, 200ppi (pixels per inch) may be the limit, while 300ppi may be the limit for RGB pixels. In addition, adding a W sub-pixel increases the number of signal channels required for each pixel by 4 / 3 times, thereby increasing the cost of the display driver integrated circuit (DDIC).

[0005] Therefore, another technical solution is needed to improve the trade-off between brightness and color gamut. Summary of the invention

[0006] The purpose of the embodiments of the present application is to provide a display panel with a pixel arrangement that can improve the trade-off between brightness and color gamut. The embodiments of the present application also provide a method for displaying an image using such a display panel, and provide a display device including such a display panel.

[0007] According to a first aspect, a display panel is provided. The display panel includes a plurality of pixel units, wherein at least one pixel unit is respectively composed of two sub-pixels, and the colors of the two sub-pixels of each pixel unit in the at least one pixel unit are in a complementary color relationship. For example, the two colors in a complementary color relationship can be selected from the group consisting of: red (R) and cyan (C); blue (B) and yellow (Y); and green (G) and magenta (M). Since each pixel unit in the at least one pixel unit includes only two sub-pixels, the number of circuit elements such as TFTs and capacitors in each pixel unit can be reduced. This may lead to compressed pixel units and improved resolution of the display panel.

[0008] In a possible implementation of the first aspect, each pixel unit in the at least one pixel unit can be used to generate a white dot when the two sub-pixels are set to a first state together, and to generate a black dot when the two sub-pixels are set to a second state together. As used herein, the "first state" of a sub-pixel refers to a state for enabling a color associated with the sub-pixel to appear, and the "second state" of a sub-pixel refers to a state for enabling a color associated with the sub-pixel to disappear. Based on two sub-pixels with complementary colors, the display panel can generate a B / W image.

[0009] In another possible implementation of the first aspect, each pixel unit in the at least one pixel unit may be configured to generate a color point associated with the one of the two sub-pixels when the one of the two sub-pixels is set to the first state and the other of the two sub-pixels is set to the second state. This may enable the ability to generate a color image.

[0010] In another possible implementation of the first aspect, each pixel unit can be driven independently. In this way, at least one pixel unit (each pixel unit includes only two sub-pixels) can be driven independently on a "pixel-by-pixel unit" basis to generate a high-resolution B / W image.

[0011] In another possible implementation of the first aspect, each pixel unit may have a centrally symmetrical shape. For example, each pixel unit may be a square or a circle. This may support retaining a traditional common pixel arrangement.

[0012] In another possible implementation of the first aspect, the area ratio of the two sub-pixels in each of the at least one pixel unit is in the range of 1:3 to 3:1, including end values. The sizes of the two sub-pixels in each of the at least one pixel unit may be the same or different. For example, the size of the sub-pixel may be determined based on reflectivity, transmittance, color filter spectrum, color particle spectrum, emission efficiency, power consumption and / or lifespan. Therefore, the size or area ratio of the two sub-pixels may be flexibly configured based on various factors, such as constraints on pixel design and / or properties of the corresponding sub-pixels.

[0013] In another possible implementation of the first aspect, the plurality of pixel units include at least two different types of pixel units, and the at least two different types of pixel units are different from each other at least in the colors of the corresponding sub-pixels. For example, the plurality of pixel units may include a plurality of first pixel units and a plurality of second pixel units alternately arranged at least in the horizontal direction, the two sub-pixels of each of the first pixel units have a first pair of colors in a complementary color relationship, and the two sub-pixels of each of the second pixel units have a second pair of colors in a complementary color relationship, and the second pair is different from the first pair. In this way, the display panel can form a pixel array in which four or more sub-pixels of different colors are distributed, and each pixel unit has only two sub-pixels of two complementary colors.

[0014] In another possible implementation manner of the first aspect, the plurality of first pixel units and the plurality of second pixel units may be arranged in a checkerboard pattern, which may make the sub-pixels of four different colors more evenly distributed.

[0015] In another possible implementation of the first aspect, the first pair and the second pair may be two of the following: R and C; B and Y; and G and M. Compared to, for example, a conventional RGB or RGBW system, two pairs of specific complementary colors may allow a larger color gamut to be represented. In addition, conventional R, G and / or B light emitting elements or filters may be used.

[0016] In another possible implementation of the first aspect, the first pair of colors and the second pair of colors both generate white points, each white point having CIE 1931 color coordinates (x, y), wherein x=0.30±0.15, y=0.33±0.10. As a preferred example, the first pair of colors and the second pair of colors can generate substantially the same white point. In this way, all pixel units can generate substantially the same white point, thereby generating a high-quality image.

[0017] In a possible implementation of the first aspect, the area ratio of the two sub-pixels in the first pixel unit is different from the area ratio of the two sub-pixels in the second pixel unit. This can support that the area ratios between the sub-pixels of four different colors can be flexibly configured according to various factors (such as emission characteristics of the corresponding sub-pixels).

[0018] In another possible implementation of the first aspect, the first pixel unit and the second pixel unit adjacent in the horizontal direction form a color pixel. This supports the generation of a color image by using color pixels, each color pixel consisting of two pixel units adjacent in the horizontal direction, while having the ability to generate a B / W image by independently driving each pixel unit. Such a color image may not result in a significant decrease in image quality for the human visual system, which will be described below.

[0019] According to a second aspect, a method for displaying an image is provided. The method comprises: converting an input image signal in a first format into an output image signal in a second format, wherein the output image signal in the second format comprises at least two pairs of color signals, each pair of color signals is in a complementary color relationship, and the at least two pairs of color signals comprise at least a first pair of color signals and a second pair of color signals, the first pair being different from the second pair. The method further comprises providing the output image signal to a display panel. The method of the second aspect supports displaying an image on a display panel according to the first aspect or any one of some possible implementations thereof using an input image signal in any preferred first format.

[0020] In a possible implementation manner of the second aspect, the first pair and the second pair may be two of the following: R and C; B and Y; and G and M. For example, an input RGB signal may be converted into an RCBY signal.

[0021] In another possible implementation of the second aspect, the display panel may include a plurality of first pixel units and a plurality of second pixel units alternately arranged at least in a horizontal direction, and providing the output image signal to the display panel includes: providing the first pair of color signals to the plurality of first pixel units; and providing the second pair of color signals to the plurality of second pixel units. For example, R and C signals may be provided to the first pixel unit, and B and Y signals may be provided to the second pixel unit.

[0022] According to a third aspect, a display device is provided, the display device comprising the display panel according to the first aspect or any possible implementation thereof. The display device further comprises a memory for storing a software program, and a processor for executing the software program and operating the display panel. For the technical advantages of the third aspect, reference may be made to the above description of the first aspect and its possible implementation.

[0023] In a possible implementation manner of the third aspect, the display device is any one of a reflective display, an emissive display or a transmissive display.

[0024] For example, the display device may be an electronic paper display (EPD). As another example, the display device may be an organic light emitting diode (OLED) display or a light emitting diode (LED) display. As yet another example, the display device may be a liquid crystal display (LCD). BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic top view showing the pixel arrangement of the display panel provided by an embodiment of the present application.

[0026] Figure 2 A diagram showing colors that are in a complementary color relationship.

[0027] Figure 3A and Figure 3B It is shown as Figure 1 Schematic top view of a variation of the pixel arrangement shown.

[0028] Figure 4A and Figure 4B It is shown as Figure 1 Schematic top views of other variations of pixel arrangements are shown.

[0029] Figure 5 It is a schematic top view showing the principle of generating a B / W image using a display panel provided by an embodiment of the present application.

[0030] Figure 6 It is a schematic top view showing the principle of generating a color image using the display panel provided by the embodiment of the present application.

[0031] Figure 7 is a schematic diagram for illustrating the YUV 4:2:2 format for reference.

[0032] Fig. 8A and Figure 8B The color gamut and color filter spectrum of the RCBY pixel provided by the embodiments of the present application are respectively shown.

[0033] Fig. 9A and Fig. 9B The color gamut and color filter spectrum of RGB pixels are shown respectively for comparison.

[0034] Fig.10 The color gamut comparison between the RCBY pixel provided by the embodiment of the present application and the RGBW pixel of the traditional solution is shown.

[0035] Figures 11 to 16is a schematic cross-sectional view showing the application of the display panel provided by the embodiment of the present application to various display technologies.

[0036] Fig.17 is a circuit diagram showing a pixel driving circuit of a display panel provided in an embodiment of the present application.

[0037] Fig.18 and Fig.19 It is a schematic diagram showing the display device architecture provided by an embodiment of the present application.

[0038] Fig. 20 is a flowchart illustrating a method for displaying an image provided by an embodiment of the present application.

[0039] Fig.21 It is a schematic diagram of a display device provided in an embodiment of the present application.

[0040] Throughout the drawings, the same or similar elements are indicated by the same or similar reference numerals. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the purpose, features and advantages of the embodiments of the present application, the technical solutions in the preferred embodiments of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0042] In the present application, the terms "first", "second", "third", etc. are intended to distinguish similar objects, such as regions, elements or structures, but do not necessarily indicate a specific order or sequence. It should be understood that these terms can be interchanged where appropriate. The terms "including", "having" and any other variants are intended to cover non-exclusive inclusions, for example, a process, method, device or system including a list of steps or elements is not necessarily limited to those steps or elements, but may include other steps or elements that are not explicitly listed or inherent to such processes, methods, devices or systems. In addition, "one" and "an" used in the present application are intended to include one or more items and can be used interchangeably with "one or more".

[0043] Figure 1The pixel arrangement of at least a portion of the display panel 100 provided by an embodiment of the present application is shown. The display panel 100 includes an array of pixel units (110, 120), each pixel unit including two sub-pixels of two colors in a complementary color relationship (respectively 112 and 114, 122 and 124). Such colors in a complementary color relationship can be mixed to produce an achromatic color. Therefore, each pixel unit of the display panel 100 can produce white when its two sub-pixels are set to a first state together, and produce black when its two sub-pixels are set to a second state together. As described herein, the "first state" of a sub-pixel refers to a state for enabling a color associated with the sub-pixel to appear, and the "second state" of a sub-pixel refers to a state for enabling a color associated with the sub-pixel to disappear. The first state and the second state can be based on a specific display technology applied to the display panel 100 (e.g., see the following description Figures 11 to 16 ). For example, in the first state, a voltage of a predetermined first polarity (which may be positive or negative) may be provided to the sub-pixel or the sub-pixel may be turned on. In the second state, a voltage of a predetermined second polarity (which may be negative or positive) may be provided to the sub-pixel or the sub-pixel may be turned off.

[0044] refer to Figure 2 , the CIE 1931 chromaticity diagram is used to illustrate colors in a complementary color relationship. On this chromaticity diagram, colors in a complementary color relationship are opposite to each other, and the white point W is located between them. Taking RGB as a reference, the complementary colors of red R, green G, and blue B can be cyan C, magenta M, and yellow Y, respectively.

[0045] Reference again Figure 1 , the plurality of pixel units of the display panel 100 may include at least two different types of pixel units, and the at least two different types of pixel units are different from each other at least in the color of the corresponding sub-pixel. The at least two different types of pixel units may include a plurality of first pixel units 110 and a plurality of second pixel units 120. The first pixel units 110 and the second pixel units 120 are alternately arranged in at least one of the horizontal direction and the vertical direction. Preferably, they may be alternately arranged in the horizontal direction. More preferably, as Figure 1 As shown, they are arranged alternately both horizontally and vertically, i.e. in a checkerboard pattern.

[0046] The two sub-pixels 112, 114 of each first pixel unit 110 have a first pair of colors in a complementary color relationship, and the two sub-pixels 122, 124 of each second pixel unit 120 have a second pair of colors in a complementary color relationship. The first pair of colors is different from the second pair of colors. For example, the first pair and the second pair can be two of R+C, G+M and B+Y. In the example shown, the first pixel unit 110 has a C sub-pixel 112 and an R sub-pixel 114, and the second pixel unit 120 has a Y sub-pixel 122 and a B sub-pixel 124. This enables adjacent first pixel units 110 and second pixel units 120 (preferably, adjacent in the horizontal direction, as described in more detail below) to form a color space having four primary colors ( Figure 1 The color pixel 130 of CRYB in the example (hereinafter also referred to as "RCBY pixel").

[0047] It should be noted that although the adjacent first pixel unit 110 and second pixel unit 120 together form a color pixel 130, they can be driven independently of each other. That is, the first pixel unit 110 can be controlled to generate achromatic color independently of the second pixel unit 120, and vice versa.

[0048] As described above, the pixel units 110, 120 driven as individual B / W pixels may each have any centrally symmetrical shape, such as a square or a circle. Figure 1 In the example shown, the pixel elements 110, 120 may be generally square. Figure 1 , the two sub-pixels (112 and 114, 122 and 124) of each pixel unit have the same size, but the embodiments of the present application are not limited thereto. For example, a conventional RGB pixel arrangement with three equally divided sub-pixels can be used to provide two sub-pixels (112 and 114, 122 and 124) with an area ratio of 2:1 (or 1:2), such as Figure 3A or Figure 3B The area ratio of the two sub-pixels can be adjusted within the range of 1:3 to 3:1 (including the end values), so that a sufficient amount of light can be obtained from the two sub-pixels, and a white point can be generated when the two sub-pixels are set together to the first state as described above.

[0049] In some embodiments, the area ratio of the sub-pixels 112 and 114 in the first pixel unit 110 may be different from the area ratio of the sub-pixels 122 and 124 in the second pixel unit 120. Preferably, both the first pixel unit 110 and the second pixel unit 120 generate white points, each of which has CIE 1931 color coordinates (x, y), where x=0.30±0.15 and y=0.33±0.10. More preferably, the first pixel unit 110 and the second pixel unit 120 may generate the same white point. Therefore, in order to make their white points as close to each other as possible, the corresponding area ratios in the first pixel unit 110 and the second pixel unit 120 may be determined according to the transmission characteristics of the color filter to be used. Alternatively or additionally, the size and / or area ratio of the two sub-pixels may be determined according to different factors, such as reflectivity, transmittance, color filter spectrum, color particle spectrum, emission efficiency, power consumption and / or life when applicable.

[0050] In addition, the direction of sub-pixel division within each pixel unit 110, 120 is not limited to Figure 1 the direction shown, Figure 1 The directions shown will result in horizontally adjacent sub-pixels. The sub-pixels may be divided in any preferred manner, for example Figure 4A or Figure 4B As shown. Figure 4A In , vertically adjacent sub-pixels can be obtained. Figure 4B In the embodiment, each of the first pixel units 110 may include vertically adjacent sub-pixels 112 and 114 , and each of the second pixel units 120 may include horizontally adjacent sub-pixels 122 and 124 .

[0051] Figure 5 The principle of generating a B / W image using the display panel 100 is shown. Figure 3B The pixel arrangements shown are used herein as examples only.

[0052] exist Figure 5 On the left side of FIG. 1 , the C and R sub-pixels 112, 114 of all first pixel units 110 are set to the second state, and the Y and B sub-pixels 122, 124 of all second pixel units 120 are set to the first state. The second pixel units 120 set to the first state can produce white through complementary colors Y and B, while the first pixel units 110 set to the second state can produce black. Figure 5, the opposite situation is shown, wherein all first pixel units 110 (both C and R sub-pixels 112, 114) are set to the first state, and all second pixel units 120 (both Y and B sub-pixels 122, 124) are set to the second state. The first pixel units 110 set to the first state can produce white through complementary colors C and R, while the second pixel units 110 set to the second state can produce black. Of course, in order to display a given B / W image, multiple first pixel units 110 can be driven independently of each other, and multiple second pixel units 120 can be driven independently of each other.

[0053] Therefore, by driving the pixel units 110, 120 as individual B / W pixels, the display panel 100 can display a B / W image on a "pixel unit by pixel unit" basis. Figure 5 It is shown that an array of 4×4 pixel units can display a B / W image having 4×4 sampling points. In this way, if the display panel 100 has an array of m×n pixel units, the display panel 100 can generate and display a B / W image having m×n sampling points.

[0054] The display panel 100 may also generate a color image within a color gamut determined by four colors of the four sub-pixels 112 , 114 , 122 , and 124 included in each color pixel 130 .

[0055] Figure 6 The principle of generating a color image using the display panel 100 is shown. Figure 3B The pixel arrangement shown is also used herein only as an example.

[0056] Figure 6 It is shown how to generate the following six colors: red, green, blue, cyan, magenta and yellow. Since there are R, B, C and Y sub-pixels in this example, red, blue, cyan and yellow can be generated by turning on only R, B, C and Y sub-pixels, respectively. In addition, green can be generated by turning on C and Y sub-pixels at the same time, and magenta can be generated by turning on R and B sub-pixels at the same time. As a result, color pixels 130 (each composed of two adjacent pixel units 110 and 120) can represent any color within the specific color gamut as described above.

[0057] Therefore, color images are displayed on a "color pixel by color pixel" basis rather than a "pixel unit by pixel" basis. Figure 6An array of 4×4 pixel units is shown to display a color image having 2×4 sampling points by driving two horizontally adjacent pixel units 110 and 120 as monochrome pixels 130. In this way, if the display panel 100 has an array of m×n pixel units, the display panel 100 can generate and display a color image having m / 2×n sampling points.

[0058] Those skilled in the art will appreciate that this has no significant impact on the overall image quality perceived by the user, because the human visual system has a higher resolution capability for B / W images and a lower resolution capability for color images. In addition, the human eye has a lower resolution in the horizontal direction than in the vertical direction. In fact, this characteristic of the human visual system is widely used in chroma subsampling techniques for image compression. Specifically, Figure 7 As shown, compared with the high-quality YUV 4:4:4 format, the YUV (or YCbCr) 4:2:2 format well known to those skilled in the art reduces the chroma sampling points by 1 / 2 in the horizontal direction while maintaining the luma sampling points. The relationship between the m / 2×n sampling points in the color image and the m×n sampling points in the B / W image as described above is equivalent to the relationship between YUV 4:2:2 and YUV 4:4:4. Therefore, the color image generated by the display panel 100 does not cause a significant decrease in image quality for the human visual system.

[0059] Therefore, it is preferred to form the color pixel 130 with two adjacent pixel units 110 and 120 in the horizontal direction rather than in the vertical direction.

[0060] Next, the display panel (for example, it may be) provided in the embodiment of the present application is described below. Figure 1 The display panel 100 shown improves the trade-off between brightness and color gamut (or color reproducibility).

[0061] Taking the above RCBY pixel as an example again, Fig. 8A The color points of these four primary colors R, C, B, and Y, and the white point W on the CIE 1931 chromaticity diagram are shown. Figure 8B The transmission spectral range of a typical color filter (CF) corresponding to these primary colors R, C, B and Y is shown. For comparison, Fig. 9A and Fig. 9B The three primary colors RGB correspond to Fig. 8A and Figure 8B .

[0062] The display panel 100 provided by the embodiment of the present application can support the use of 4 primary colors ( Fig. 8A ) instead of 3 primary colors ( Fig. 9A) to cover a wider color gamut. In addition, the commonly used R, G and B color filters have a relatively large overlap in their absorption ranges ( Fig. 9B ), and may reduce the brightness of white light obtained from RGB pixels. In contrast, a combination of R and C color filters and a combination of B and Y color filters (which are in a complementary color relationship, respectively) can reduce such overlap in their absorption ranges ( Figure 8B ). Therefore, the first pixel unit 110 including the R and C sub-pixels and the second pixel unit 120 including the B and Y sub-pixels can respectively increase the brightness of white light. Therefore, the display panel 100 can improve the trade-off between brightness and color gamut.

[0063] This can be better understood when comparing in the CIE L*a*b* (CIELAB) color space. The CIELAB color space model is closer to the characteristics of the human visual system than the CIE 1931 color space.

[0064] For example, Fig.10 The color gamut comparison between the RCBY pixel provided by the embodiment of the present application and the RGBW pixel of the existing solution is shown. As an example of industrial standards, Fig.10 Also shown is the color gamut required by the Specifications for Newsprint Advertising Production (SNAP), which is commonly used in the printing industry using the CMYK color ink system.

[0065] It can be clearly seen that RCBY pixels have a larger color gamut than RGBW pixels. Especially in the yellow region, the color gamut of RCBY pixels may be significantly expanded, close to the SNAP requirement. This means that the display panel provided by the embodiment of the present application also has significant advantages in color e-book type products.

[0066] The reflective EPD panels currently used for e-books have very low reflectivity (resulting in low brightness) and very poor color gamut. For example, when using traditional RGB pixels, the maximum achievable reflectivity and color gamut can be approximately 25% and 15% NTSC ratio, respectively, and when using RGBW pixels of the existing solution, they are approximately 30% and 15% NTSC ratio, respectively. On the other hand, the display panel provided by the embodiments of the present application can support the realization of performance indicators such as 35% reflectivity and a color gamut greater than 20% NTSC ratio.

[0067] In addition, each pixel unit of the display panel provided by the embodiment of the present application includes only two sub-pixels, while the RGB pixel includes three sub-pixels and the RGBW pixel includes four sub-pixels. In other words, each pixel unit may include only two TFTs and two storage capacitors. This can support compression of each pixel unit to improve the resolution of the display panel. For example, although RGB pixels and RGBW pixels have resolution limits of approximately 300ppi and 200ppi, respectively, the display panel provided by the embodiment of the present application supports a resolution higher than 300ppi.

[0068] Furthermore, such a reduction in the number of sub-pixels supports a reduction in the number of signal channels per pixel unit, thereby reducing the cost of a display driver integrated circuit (DDIC).

[0069] Reference now Figures 11 to 16 , various structures of the display panel provided by the embodiments of the present application will be described. Figures 11 to 16 are schematic cross-sectional views showing the application of the display panel provided by the embodiment to various display technologies. These cross-sectional views correspond to Figure 1 The portions of two adjacent pixel units 110 and 120 (i.e., portions of a color pixel 130) are shown. Figures 11 to 16 , again taking RCBY pixels as an example.

[0070] Fig.11 An exemplary application of an electrophoretic display is shown. Such an electrophoretic display is generally used in an electronic paper display (EPD), which may also be referred to as an "EPD". The EPD panel 1100 includes the above-mentioned pixel arrangement as a color filter layer 1110. The EPD panel 1100 also includes a lower substrate 1120, an upper substrate 1130, and a microcapsule 1140 disposed between the lower substrate 1120 and the upper substrate 1130. The lower substrate 1120 includes a pixel driving circuit (not shown herein), and a plurality of sub-pixel electrodes 1150 are disposed on the upper surface facing the microcapsule 1140. Each sub-pixel electrode in the sub-pixel electrode 1150 corresponds to a sub-pixel. Therefore, each sub-pixel electrode in the sub-pixel electrode 1150 is aligned with a corresponding one of the R, B, C, and Y color filters of the color filter layer 1110. The upper substrate 1130 is a transparent substrate, and a transparent common electrode 1160 for a plurality of sub-pixels is disposed on its lower surface.

[0071] It should be understood that Fig.11One microcapsule 1140 per sub-pixel is shown, but in practice, for example, tens of microcapsules 1140 may be provided within each sub-pixel. Each microcapsule 1140 encapsulates a dispersion containing black (BLK) particles 1142 and white (W) particles 1144, and the BLK particles 1142 and the W particles 1144 carry charges of opposite polarities. Thus, the EPD panel 1100 may be configured as a combination of Figure 5 and Figure 6 In the manner described, a given B / W image or color image is displayed by controlling the voltage applied to the subpixel electrode 1150 to move the particles 1142 and 1144 in the microcapsule 1140. For example, in the case where the BLK particles 1142 are positively charged and the W particles 1144 are negatively charged, a negative voltage applied to the subpixel causes the W particles 1144 to move upward, making the W particles 1144 visible to a user or viewer of the EPD panel 1100. For the EPD panel 1100, applying a voltage to the subpixel to make the W particles 1144 visible may correspond to setting the subpixel to a first state.

[0072] Fig.12 Another exemplary application of an electrophoretic display is shown. The EPD panel 1200 includes Fig.11 The components in the illustrated EPD panel 1100 are identical or similar components. These components are indicated by identical or similar reference numerals and are not described again herein.

[0073] EPD Panel 1200 not included Fig.11 Instead of the color filter layer 1110 shown in FIG. 1 , the microcapsules 1240 include color particles 1244. Specifically, the microcapsules 1240 in the C, R, Y, and B sub-pixels include C, R, Y, and B particles 1244, respectively, and BLK particles 1142. Fig.11 EPD panel 1100 is shown, and EPD panel 1200 can display a given B / W image or color image by controlling the voltage applied to subpixel electrode 1150 to move particles 1142 and 1244 in microcapsule 1240. For EPD panel 1200, applying a voltage to a subpixel to make color particle 1244 visible can correspond to setting the subpixel to a first state.

[0074] Fig.13 FIG. 1 shows an exemplary application of a liquid crystal display (LCD). The LCD panel 1300 includes Fig.11 The components in the illustrated EPD panel 1100 are identical or similar components. These components are indicated by identical or similar reference numerals and are not described again herein.

[0075] The LCD panel 1300 does not include a microcapsule, but includes a liquid crystal layer 1340. In an embodiment of the present application, the liquid crystal layer 1340 may include any of various types known to those skilled in the art. The LCD panel 1300 may display a given B / W image or color image by controlling the voltage applied to the sub-pixel electrode 1150 to change the light transmission through the liquid crystal layer 1340. For the LCD panel 1300, applying a voltage to the sub-pixel so that the liquid crystal layer 1340 can transmit light may correspond to setting the sub-pixel to a first state.

[0076] Fig.14 FIG. 14 shows an exemplary application of an organic light emitting diode (OLED) display. The OLED display panel 1400 includes Fig.11 The components in the illustrated EPD panel 1100 are identical or similar components. These components are indicated by identical or similar reference numerals and are not described again herein.

[0077] The OLED display panel 1400 is of an emissive type and does not require a color filter layer, as in Fig.11 and Fig.13 The color filter layer 1110 is shown. The C, R, Y, and B sub-pixels include an OLED layer 1440 that emits light of C, R, Y, and B colors, respectively, between the sub-pixel electrode 1150 and the transparent common electrode 1160. The OLED display panel 1400 can display a given B / W image or a color image by controlling the voltage applied to the sub-pixel electrode 1150 and thereby controlling the light emission from the corresponding OLED layer 1440. For the OLED display panel 1400, turning on the OLED layer 1440 in the sub-pixel to emit light can correspond to setting the sub-pixel to a first state.

[0078] It should be noted that Fig.14 The structure of the OLED display panel 1400 shown is also applicable to an emission-type quantum dot (QD) display.

[0079] Fig.15 FIG. 15 shows an exemplary application of a light emitting diode (LED) display. The LED display panel 1500 includes Fig.11 The components in the illustrated EPD panel 1100 are identical or similar components. These components are indicated by identical or similar reference numerals and are not described again herein.

[0080] LED display panel 1500 is also of the emission type and does not require a color filter layer, as in Fig.11 and Fig.13The color filter layer 1110 is shown. The C, R, Y, and B sub-pixels include LED dies 1540 that emit light of C, R, Y, and B colors, respectively. Fig.15 In the example shown, the LED die 1540 is a flip chip die, and the lower substrate 1120 in each sub-pixel is provided with at least two electrodes 1520 connected to the anode and cathode of the corresponding LED die. The LED display panel 1500 can display a given B / W image or color image by controlling the voltage applied to the electrodes 1520 in the sub-pixel and thus controlling the light emission from the corresponding LED die 1540. For the LED display panel 1500, turning on the LED die 1540 in the sub-pixel to emit light can correspond to setting the sub-pixel to a first state.

[0081] Fig.16 Another exemplary application of LED display is shown. The LED display panel 1600 includes Fig.15 The components in the LED display panel 1500 shown are the same or similar components. These components are indicated by the same or similar reference numerals and are not described again here.

[0082] The LED display panel 1600 includes a blue LED die 1640 in each sub-pixel. The LED display panel 1600 also includes a color conversion layer 1645 of a different color above the blue LED die 1640. The color conversion layer 1645 may be supported by a transparent upper substrate, such as Fig.11 The upper substrate 1130 shown. The color conversion layer 1645 in the C, R and Y sub-pixels can convert the blue light from the underlying blue LED tube core 1640 into cyan, red and yellow, respectively. The color conversion layer 1645 in the B sub-pixel can be transparent to the blue light from the underlying blue LED tube core 1640. Therefore, this can omit or not include any color conversion material. The LED display panel 1600 can display a given B / W image or color image by controlling the voltage applied to the electrode 1520 in the sub-pixel and thereby controlling the light emission from the corresponding blue LED tube core 1640 under the color conversion layer 1645. For the LED display panel 1600, turning on the blue LED tube core 1640 in the sub-pixel to emit light can correspond to setting the sub-pixel to a first state.

[0083] Fig.17 1 is a circuit diagram showing a pixel driving circuit of a display panel 1700 provided in an embodiment of the present application. The display panel 1700 may be, for example, Figures 11 to 16 The circuit diagram shows any one of the display panels 1100 to 1600. Figure 1In other words, since each pixel cell includes two sub-pixels, the circuit diagram corresponds to a pixel cell (e.g., Figure 1 When two horizontally adjacent pixel cells form a color pixel, this may also correspond to a color pixel (e.g., Figure 1 Part of a 1×3 array of color pixels 130).

[0084] The driving circuit in each sub-pixel may include a TFT 1710, a storage capacitor 1720, a sub-pixel electrode 1730, and a common electrode 1740. The drain of the TFT 1710 is connected to a corresponding one of the data lines (e.g., Data1, Data 2, Data3, Data 4, etc.), and the source of the TFT 1710 is connected to a corresponding one of the storage capacitor 1720 and the sub-pixel electrode 1730. The gate of the TFT 1710 is connected to a corresponding one of the gate lines (e.g., Gate1, Gate2, Gate3, Gate4, etc.). The common electrode 1740 may be connected to a corresponding one of the common voltage (VCOM) lines, and the other electrode of the storage capacitor 1720 may be connected to a corresponding one of the storage capacitor (CS) lines. It should be noted that the other electrode of the storage capacitor 1720 may be connected to the VCOM line as the common electrode 1740, and in this case the CS line may be omitted.

[0085] According to an embodiment of the present application, two sub-pixels in each pixel unit are used to receive data voltages of two colors in a complementary color relationship, as described above. In addition, two adjacent pixel units are used to receive data voltages of different pairs of complementary colors. Therefore, when a given gate line (e.g., Gate1) is driven, data lines Data1 and Data2 can provide data voltages of two colors in a complementary color relationship (e.g., R and C), and data lines Data3 and Data4 can provide data voltages of two other colors in a complementary color relationship (e.g., B and Y). Therefore, 4 primary color (e.g., RCBY) signals will be provided to the display panel 1700.

[0086] Reference now Fig.18 and Fig.19 , describes an exemplary display device architecture for generating such a four-primary color (e.g., RCBY) signal.

[0087] Fig.18 The display device 1800 provided by an embodiment of the present application is schematically shown. The display device 1800 includes a panel, which may be a reference Fig.17The display panel 1700 described above. The display device 1800 may further include a printed circuit board (PCB) 1810 and a flexible printed circuit board (FPC) 1820 that connects the display panel 1700 to the PCB 1810. The FPC 1820 may support the display panel 1700 and the PCB 1810 to be placed back to back in the housing ( Fig.18 Not shown).

[0088] The display device 1800 may further include a DDIC 1830, a timing controller (TCON) 1840, and a power supply circuit 1850. The DDIC 1830 may be mounted near the display panel 1700, for example, as shown in the figure, mounted on the FPC 1820. Alternatively, the DDIC 1830 may be mounted or formed on a substrate of the display panel 1700 itself. The TCON 1840 may be mounted on the PCB 1810 and provide various signals to the DDIC 1830 and, optionally, to the display panel 1700. The power supply circuit 1850 may be provided on the PCB 1810 and provide one or more power supply voltages and a ground voltage to the DDIC 1830 and the display panel 1700. For example, the power supply circuit 1850 may supply a ground voltage as a common voltage directly to a common voltage (VCOM) line ( Fig.17 ).

[0089] refer to Fig.19 , the four primary color (e.g., RCBY) signals provided to the display panel 1700 may be generated by a processing circuit 1900 in the DDIC 1830 or the TCON 1840, such as an intellectual property (IP) circuit. The IP circuit 1900 may include an interface (I / F) 1910 for receiving an input image signal from a host side, a gamma (γ) circuit 1920, a conversion circuit 1930, and an inverse gamma (γ) circuit. –1 ) circuit 1940. For example, the input image signal may be an RGB signal, and the 4 primary color signals provided to the display panel 1700 may be RCBY signals. At this time, the conversion circuit 1930 is used to perform RGB-RCBY conversion. The γ circuit 1920 and the γ –1 Circuit 1940 performs gamma correction, which is well known to those skilled in the art and will not be described in detail here.

[0090] The IP circuit 1900 may provide the generated RCBY signal to the display panel 1700. More specifically, the IP circuit 1900 may provide the generated RCBY signal to the first pixel unit (eg, Figure 1 The first pixel unit 110 in the display panel 1700 provides a first pair of R and C signals in a complementary color relationship, and provides a second pixel unit (eg, Figure 1 The display panel 1700 may then display an image based on the RCBY signal received from the IP circuit 1900.

[0091] Fig. 20 2 is a flow chart showing a method 2000 for displaying an image provided by an embodiment of the present application. The method 2000 may be executed by a processing circuit, for example Fig.19 IP circuit 1900 is shown.

[0092] In step 2010, method 2000 includes converting an input image signal in a first format into an output image signal in a second format. The image signal in the second format includes a first pair of color signals in a complementary color relationship and a second pair of color signals in a complementary color relationship. The first pair of color signals is different from the second pair of color signals. That is, the first pair of color signals and the second pair of color signals together provide a 4-primary color signal.

[0093] For example, the first pair of color signals and the second pair of color signals are two of the following: red (R) and cyan (C) signals; blue (B) and yellow (Y) signals; and green (G) and magenta (M) signals. In a specific example, the input image signal is an RGB signal, the first pair of color signals are R and C signals, and the second pair of color signals are B and Y signals.

[0094] In step 2020, the method 2000 includes providing an output image signal to a display panel. A first pair of color signals in a complementary color relationship may be provided to a plurality of first pixel units (eg, Figure 1 The first pixel unit 110 in the embodiment of the present invention can provide a second pair of color signals in a complementary color relationship to a plurality of second pixel units (eg, Figure 1 The second pixel unit 120 in the display panel is alternately arranged with the first pixel units. It should be noted that if the display panel supports three or more pairs of color signals, other embodiments of the present application can provide three or more pairs of color signals as image signals in the second format.

[0095] Reference now Fig.21, a schematic diagram of a display device 2100 provided by an embodiment of the present application is shown. In some embodiments, the display device 2100 may be a battery-powered mobile device, such as an e-book reader, a smart phone, a smart watch, a tablet computer, a laptop computer, etc. In other embodiments, the display device 2100 may be a device that is typically connected to a public power source, such as a television or a monitor, or a device that is typically connected to an external battery, such as a car display. In addition, the display device 2100 may be any other device, such as a digital signage device, regardless of the type of power source.

[0096] exist Fig.21 In the example shown, the display device 2100 includes a processor 2110, a memory 2120, a battery 2130, and a display panel 2140. The display panel 2140 can be assembled with the housing of the display device 2100 in such a way that a user of the display device 2100 can see the front surface of the display panel 2140, such as Fig.21 The processor 2110, the memory 2120 and the battery 2130 may be contained in the housing, as shown in the solid line in FIG. Fig.21 The processor 2110, the memory 2120, the battery 2130, and the display panel 2140 may be electrically connected to each other.

[0097] Although not shown, the display device 2100 may optionally include a radio frequency (RF) circuit, a speaker, a microphone, an input device, a sensor, a camera, an antenna, a near field communication module, and the like.

[0098] The processor 2110 can be used to call the software program and data stored in the memory 2120 and execute the software program to perform various functions and / or data processing of the display device 2100. The processor 2110 may include any suitable dedicated or general processing device or unit. In addition, the processor 2110 may include any suitable number of processors. For example, the processor 2110 may include a microprocessor, a microcontroller, an application processor, a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), etc. One or more. In one example, the processor 2110 may include Fig.18One or more processors in DDIC 1830 and one or more processors in TCON 1840 are shown, and execute Fig. 20 Method 2000 is shown.

[0099] The memory 2120 can be used to store software programs and data, and can include any suitable medium that can be accessed by the processor 2110. In addition, the memory 2120 can include any suitable number of memories. The memory 2120 may include volatile memory and / or non-volatile memory, and may include, for example, random access memory (RAM), read-only memory (ROM) and / or flash memory. It should be noted that the term "memory" as used herein may refer to a large-capacity memory capable of storing a large amount of data (including content to be displayed on the display panel 2140). Therefore, the memory 2120 may also include, for example, a hard disk drive (HDD), a solid state drive (SDD), an optical drive, etc.

[0100] The battery 2130 may be used to power various components of the display device 2100 (e.g., the processor 2110, the memory 2120, the display panel 2140, etc.). The processor 2110 may run a power management program or module stored in the memory 2120 to control the power consumption of one or more components and the charging and discharging of the battery 2130. In addition to or in place of the battery 2130, the display device 2100 may have a power connector, an adapter, etc. connected to an external power source (e.g., a utility power source).

[0101] The display panel 2140 may be used to display various information and content, including information input by a user and information provided to the user. The display panel 2140 may include a user input device, such as a touch screen, on at least a portion of a surface exposed from the housing.

[0102] The display panel 2140 may be, for example, Figure 1 The display panel 100 is shown. Therefore, each pixel unit of the display panel 2140 may have two sub-pixels of two colors in a complementary color relationship, thereby improving the trade-off between brightness and color gamut.

[0103] Although some preferred embodiments of the present application have been described, those skilled in the art may change and modify these embodiments without departing from the scope of the present disclosure. Therefore, the appended claims are intended to be interpreted as covering all changes and modifications that fall within the scope of the present disclosure. It should also be noted that errors in values ​​and ranges due to engineering implementation are also within the scope of the present disclosure.

Claims

1. A display panel, It is characterized in that It comprises a plurality of pixel units, wherein at least one pixel unit is composed of two sub-pixels, and the colors of the two sub-pixels of each pixel unit in the at least one pixel unit are in a complementary color relationship.

2. The display panel according to claim 1, It is characterized in that Each pixel unit of the at least one pixel unit is configured to generate a white point when the two sub-pixels are together set to a first state.

3. The display panel according to claim 2, It is characterized in that Each pixel unit of the at least one pixel unit is configured to generate a black dot when the two sub-pixels are set together to a second state.

4. The display panel according to claim 3, It is characterized in that Each pixel cell of the at least one pixel cell is configured to generate a color point associated with the one of the two sub-pixels when the one of the two sub-pixels is set to the first state and the other of the two sub-pixels is set to the second state.

5. The display panel according to any one of claims 1 to 4, It is characterized in that Each pixel unit is driven independently.

6. The display panel according to any one of claims 1 to 5, It is characterized in that Each pixel unit has a centrally symmetrical shape.

7. The display panel according to claim 6, It is characterized in that Each pixel unit is square or circular.

8. The display panel according to any one of claims 1 to 7, It is characterized in that An area ratio of the two sub-pixels in each of the at least one pixel unit is in a range of 1:3 to 3:1, inclusive.

9. The display panel according to claim 8, It is characterized in that The area ratio of the two sub-pixels is determined according to reflectivity, transmittance, color filter spectrum, color particle spectrum, emission efficiency, power consumption and / or lifespan.

10. The display panel according to any one of claims 1 to 9, It is characterized in that The plurality of pixel units include at least two different types of pixel units, and the at least two different types of pixel units are different from each other at least in colors of corresponding sub-pixels.

11. The display panel according to claim 10, It is characterized in that The multiple pixel units include a plurality of first pixel units and a plurality of second pixel units alternately arranged at least in a horizontal direction, wherein the two sub-pixels of each of the first pixel units have a first pair of colors in a complementary color relationship, and the two sub-pixels of each of the second pixel units have a second pair of colors in a complementary color relationship, and the second pair of colors is different from the first pair of colors.

12. The display panel according to claim 11, It is characterized in that The plurality of first pixel units and the plurality of second pixel units are arranged in a checkerboard pattern.

13. The display panel according to claim 11 or 12, It is characterized in that The first pair of colors and the second pair of colors are two of the following: red and cyan; blue and yellow; green and magenta.

14. The display panel according to any one of claims 11 to 13, It is characterized in that The first pair of colors and the second pair of colors both produce white points, each white point having CIE 1931 color coordinates (x, y), where x=0.30±0.15, y=0.33±0.

10.

15. The display panel according to any one of claims 11 to 14, It is characterized in that The first pair of colors and the second pair of colors produce the same white point.

16. The display panel according to any one of claims 11 to 15, It is characterized in that An area ratio of the two sub-pixels in the first pixel unit is different from an area ratio of the two sub-pixels in the second pixel unit.

17. The display panel according to any one of claims 11 to 16, It is characterized in that The first pixel unit and the second pixel unit adjacent to each other in the horizontal direction form a color pixel.

18. A method for displaying an image, It is characterized in that The method comprises: Converting an input image signal in a first format into an output image signal in a second format, wherein the output image signal in the second format includes at least two pairs of color signals, each pair of color signals is in a complementary color relationship, the at least two pairs of color signals include at least a first pair of color signals and a second pair of color signals, the first pair of color signals being different from the second pair of color signals; The output image signal is provided to a display panel.

19. The method according to claim 18, It is characterized in that The first pair of color signals and the second pair of color signals are two of the following: red and cyan signals; blue and yellow signals; green and magenta signals.

20. The method according to claim 18 or 19, It is characterized in that The display panel includes a plurality of first pixel units and a plurality of second pixel units alternately arranged at least in a horizontal direction, wherein providing the output image signal to the display panel includes: providing the first pair of color signals to the plurality of first pixel units; The second pair of color signals is provided to the plurality of second pixel units.

21. A display device, It is characterized in that include: The display panel according to any one of claims 1 to 17; Memory for storing software programs; A processor is used to execute the software program and operate the display panel.

22. The display device according to claim 21, It is characterized in that The display device is an electronic paper display (EPD).

23. The display device according to claim 21, It is characterized in that The display device is an organic light emitting diode (OLED) display or a light emitting diode (LED) display.

24. The display device according to claim 21, It is characterized in that The display device is a liquid crystal display LCD.

Images