Electrophoretic reflective display

Abstract

The invention discloses an electrophoretic reflective display which comprises an electrophoretic display layer and a color filter structure arranged above the electrophoretic display layer, the color filter structure comprises a plurality of color filter sub-pixels and non-filter areas located between the adjacent color filter sub-pixels, and the electrophoretic reflective display further comprises an anti-crosstalk light control structure, the anti-crosstalk light-operated structure is used for reducing light crosstalk between two adjacent color filtering sub-pixels and effectively guiding or blocking high-scattering light rays from an electrophoretic display layer, so that the light crosstalk between the two adjacent color filtering sub-pixels is obviously inhibited; on the premise of basically maintaining the characteristics of low power consumption, high scattering paper feeling and wide viewing angle of the reflective display, the problem of insufficient color purity is fundamentally solved, and the overall color saturation is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of electrophoretic display technology, and more particularly to an electrophoretic reflective display. Background Technology

[0002] Electrophoretic displays (EPDs) are a type of reflective display technology. Their main characteristic is the use of ambient or front-lit reflection for image formation. Compared to self-emissive or backlit display technologies, EPDs have high diffuse reflection characteristics, with reflected light distribution closely resembling Lambertian scattering. This allows the displayed image to maintain stable brightness and contrast at different viewing angles. This feature makes EPDs visually closer to traditional paper, reducing glare and visual strain caused by self-emissive or backlit structures, and lowering the visual burden on the human eye.

[0003] To achieve color display, existing technologies typically involve placing a color filter array (CFA) above the display panel. By selectively absorbing reflected light at specific wavelengths, different sub-pixels display corresponding colors. This architecture can achieve colorization while maintaining the display characteristics of existing electrophoretic displays and is compatible with existing monochrome electrophoretic displays, making it the mainstream approach for consumer-grade color electrophoretic displays today.

[0004] Existing electrophoretic reflective displays using color filters still have limitations in color saturation performance. The main reason is the high scattering characteristic of the electrophoretic display layer, which causes light to be distributed at multiple angles before passing through the color filter. Color filters form colors by absorbing light from non-target wavelengths, and their spectral selectivity design is suitable for light emitters with high directionality and energy density. Under highly scattered reflected light, a large amount of light energy is absorbed or lost in the color filter, significantly reducing the effective spectral energy for color formation, resulting in low color saturation and a grayish visual effect. Figure 1 or Figure 2 The existing electrophoretic display with color filter 01 shown has a high scattering characteristic. After reflection, the light passing through a single color filter sub-pixel 011 will be diffused, causing the light to mix with other color filter sub-pixels 011, resulting in a decrease in color saturation.

[0005] In addition, existing technologies often improve overall color saturation by increasing the absorption rate or color purity of color filters. Such approaches are often accompanied by more severe light energy loss, which limits the possibility of improving color saturation of reflective displays while maintaining a paper-like feel and low visual burden.

[0006] Therefore, how to improve color saturation by improving the architecture of color filters without compromising the reflective, high-scattering, and paper-like characteristics of electrophoretic displays remains an unsolved problem in current technology. Summary of the Invention

[0007] The purpose of this invention is to provide an electrophoretic reflective display.

[0008] The technical solution adopted in this invention is:

[0009] An electrophoretic reflective display includes an electrophoretic display layer and a color filter structure disposed above the electrophoretic display layer. The color filter structure includes a plurality of color filter sub-pixels and a non-filtered area located between adjacent color filter sub-pixels. It also includes an anti-crosstalk light control structure for reducing optical crosstalk between two adjacent color filter sub-pixels.

[0010] Furthermore, the anti-crosstalk light control structure includes a barrier wall disposed in the electrophoretic display layer and corresponding to each non-filtering area, the barrier wall being made of a highly reflective material or a highly absorbent material.

[0011] Furthermore, an optical adhesive layer is provided between the electrophoretic display layer and the color filter structure. A high-reflectivity layer or a high-absorption layer is filled on the optical adhesive layer at the positions corresponding to each non-filter area to form the anti-crosstalk light control structure.

[0012] Furthermore, the anti-crosstalk light control structure includes a high light-absorbing layer filling the non-filtering area, and a high light-absorbing protrusion structure or a high light-reflecting protrusion structure is combined below the high light-absorbing layer.

[0013] Furthermore, the thickness of the high light-absorbing layer is 0.01 micrometers to 5 micrometers, and the height of the high light-absorbing protrusion structure or the high light-reflecting protrusion structure is 0.5 micrometers to 40 micrometers.

[0014] Furthermore, the anti-crosstalk light control structure includes a high light absorption layer filled in the non-filtering area, a high reflective layer superimposed below the high light absorption layer, and a high light absorption protrusion structure or a high reflective light protrusion structure combined below the high reflective layer.

[0015] Furthermore, the thickness of the high light-absorbing layer and the high light-reflecting layer is 0.01 micrometers to 5 micrometers, and the height of the high light-absorbing protrusion structure or the high light-reflecting protrusion structure is 0.5 micrometers to 40 micrometers.

[0016] Furthermore, the high light absorption protrusion structure and the high light reflection protrusion structure are circular columnar, square columnar, trapezoidal columnar, or pyramidal.

[0017] Furthermore, the color filter sub-pixels are arranged in a striped, triangular, or staggered pattern.

[0018] Furthermore, the projected area of ​​the anti-crosstalk optical control structure on the plane where the color filter structure is located accounts for 1% to 45% of the total area of ​​all color filter sub-pixels.

[0019] The present invention adopts the above technical solution and has the following beneficial technical effects: By setting an anti-crosstalk light control structure in the non-filtering area of ​​the color filter, the present invention effectively guides or blocks the highly scattered light from the electrophoretic display layer, thereby significantly suppressing the light crosstalk between two adjacent color filter sub-pixels. While basically maintaining the low power consumption, high scattering paper feel and wide viewing angle characteristics of the reflective display, the present invention fundamentally solves the problem of insufficient color purity and achieves a significant improvement in overall color saturation. Attached Figure Description

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments;

[0021] Figure 1 This is a schematic diagram of an electrophoretic display with a baffle in the prior art;

[0022] Figure 2 This is a schematic diagram of an electrophoretic display with an optical adhesive layer in the prior art;

[0023] Figure 3 This is a schematic diagram of Embodiment 1 of the present invention;

[0024] Figure 4 This is a schematic diagram of Embodiment 2 of the present invention;

[0025] Figure 5 This is a schematic diagram of Embodiment 3 of the present invention;

[0026] Figure 6 This is a schematic diagram of Embodiment 4 of the present invention;

[0027] Figure 7 This is a schematic diagram of Embodiment 5 of the present invention;

[0028] Figure 8 This is a schematic diagram showing that the color filter subpixels are arranged in a stripe pattern.

[0029] Figure 9 This is a schematic diagram showing the triangular arrangement of color filter sub-pixels;

[0030] Figure 10 This is a schematic diagram showing the staggered arrangement of color filter subpixels. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0032] like Figure 3-7 As shown, the present invention discloses an electrophoretic reflective display, including an electrophoretic display layer 2 and a color filter structure 1 disposed above the electrophoretic display layer 2. The color filter structure 1 includes a plurality of color filter sub-pixels 11 and a non-filtering region 12 located between adjacent color filter sub-pixels 11. It also includes an anti-crosstalk light control structure, which is used to reduce light crosstalk between two adjacent color filter sub-pixels 11.

[0033] Example 1, Figure 3 As shown, the anti-crosstalk light control structure in this embodiment is a barrier 3 disposed in the electrophoretic display layer 2 and corresponding to each non-filter area 12. The barrier 3 is made of a highly reflective material or a highly absorbent material. By setting the barrier 3, the light crosstalk between adjacent color filter sub-pixels 11 can be reduced to a certain extent, thereby improving color saturation.

[0034] Example 2, Figure 4 As shown, an optical adhesive layer is provided between the electrophoretic display layer 2 and the color filter structure 1. During the process of attaching the OCA or OCR optical adhesive layer 7, a high reflective layer or a high light-absorbing layer 8 is filled on the optical adhesive layer 7 at the positions corresponding to each non-filter area 12 to form an anti-crosstalk light control structure. This can also reduce light crosstalk between two adjacent color filter sub-pixels 11 to a certain extent, thereby improving color saturation.

[0035] In Embodiments 1 and 2 above, when a high-reflectivity material is used in the anti-crosstalk light control structure, the light reflected from the electrophoretic display layer 2 is guided and re-enters the corresponding color filter sub-pixels 11 to ensure brightness. When the brightness is sufficient, a high-absorption material can be used in the anti-crosstalk light control structure to absorb and block the light reflected from the electrophoretic display layer 2. Since the non-filtering area 12 of the color filter structure 1 is a blank structure or filled with a high-transmittance material, a small portion of reflected light will still enter adjacent color filter sub-pixels 11, causing optical crosstalk. To avoid optical crosstalk caused by a small portion of reflected light, the following embodiments provide further optimization.

[0036] Example 3, as Figure 5 As shown, a black high-absorption layer 4 is filled in the non-filtering area 12 of the color filter structure 1. This absorbs reflected light passing through the non-filtering area 12, thereby improving overall color saturation. Although this design may reduce overall brightness, it can effectively improve color saturation. Furthermore, a barrier 3 disposed in the electrophoretic display layer 2 can be further integrated below the high-absorption layer 4. The barrier 3 can be made of a high-reflectivity material or a high-absorption material. The function of the barrier 3 is the same as in Embodiment 1.

[0037] Example 4, as Figure 6As shown, a thin, black, high-absorption layer 4 is filled at the top of the non-filtering area 12 of the color filter structure 1, and a high-reflection layer 5 is provided below the high-absorption layer 4. A protrusion structure 6 can be fabricated below this high-reflection layer 5 using a manufacturing process. The protrusion structure 6 extends into the electrophoretic display layer 2. This protrusion structure 6 can be a high-absorption protrusion structure or a high-reflection protrusion structure, serving to block light or reflect and reuse light. In this embodiment, the high-absorption layer 4 avoids light crosstalk and improves color saturation, while the high-reflection layer 5 guides reflected light to re-incidentally reach the corresponding sub-pixel area, ensuring brightness.

[0038] Example 5, as Figure 7 As shown, a thin black high-absorption layer 4 is filled at the top of the non-filtering area 12 of the color filter structure 1. The thickness of the high-absorption layer 4 is the same as or similar to the thickness of the color filter structure 1. A protrusion structure 6 is attached below the high-absorption layer 4. The protrusion structure 6 is located in the electrophoretic display layer 2. The protrusion structure 6 can be a high-absorption protrusion structure or a high-reflection protrusion structure, which serves to block light or reflect and reuse light.

[0039] In Examples 4 and 5, the specific shape of the high-absorption or high-reflection protrusion structure is not limited; it can be a circular column, a square column, a trapezoidal column, or a pyramidal shape, etc. The height of the high-absorption layer 4, the high-reflection layer 5, and the high-absorption or high-reflection protrusion structure depends on the thickness of the electrophoretic display layer and the size of the electrophoretic particles, and is generally 0.5 micrometers to 40 micrometers.

[0040] In the above embodiments, the materials of the high-absorption layer, the high-absorption protrusion structure, and the high-absorption material can be dark-colored chromium oxide or dark-colored resin. The materials of the high-reflection layer, the high-emission protrusion structure, and the high-reflection material can be one or a mixture of two or more of the following: silicon dioxide, titanium dioxide, barium oxide, barium sulfate, aluminum oxide, aluminum hydroxide, zirconium oxide, calcium oxide, calcium carbonate, calcium phosphate, calcium hydroxide, magnesium hydroxide, magnesium oxide, zinc oxide, zinc sulfide, germanium oxide, and antimony oxide; or any element or alloy of gold, silver, copper, chromium, aluminum, germanium, antimony, magnesium, zinc, and molybdenum.

[0041] In this invention, the color filter structure can adopt different sub-pixel arrangements according to display requirements, such as striped, triangular, and staggered arrangements. Since different arrangements have different periodicity and symmetry in the spatial direction, this invention further designs the anti-crosstalk light control structure (including high-reflection layer, black high-absorption layer, etc.) in the non-filter area and the light emission direction of the front light guide plate according to each arrangement, so as to improve the effective utilization rate of reflected light.

[0042] In one embodiment, the color filter sub-pixels are arranged in a stripe pattern, with each sub-pixel having a continuously extending structure in a first direction (horizontal or vertical) and a periodic boundary in a second direction. In this arrangement, it is necessary to prevent the diffusion of reflected light from the electrophoretic display layer or the front light guide plate. Therefore, in this embodiment, an anti-crosstalk light control structure can be selected in the non-filtering area of ​​the second direction, while the configuration of the anti-crosstalk light control structure is reduced or omitted in the non-filtering area corresponding to the stripe extension direction. This method avoids unnecessary shading or light loss, and allows reflected light to be more effectively redirected to adjacent color filter sub-pixels of the same color, thereby improving the color saturation of this arrangement.

[0043] Figure 8 As shown, each color filter sub-pixel is arranged in a stripe pattern (left). The anti-crosstalk light control structure (replaced only by a black high absorption layer) can be selected to be set only in the non-filter area of ​​the second direction (right). In the non-filter area of ​​the first direction corresponding to the stripe extension direction, the filter material can be directly patterned or left blank.

[0044] In another embodiment, the color filter subpixels are arranged in a triangular pattern, with each subpixel forming slanted boundaries in multiple directions and lacking a single main extension direction. In this case, the reflected light and the light output direction of the front light guide plate may be distributed in multiple directions. In this invention, an anti-crosstalk light control structure can be configured in the non-filtering areas of multiple adjacent boundaries of each subpixel, and its width or reflection characteristics can be adjusted according to the geometry of the subpixel to redirect highly scattered reflected light in multiple directions.

[0045] like Figure 9 As shown, the color filter sub-pixels are arranged in a triangular pattern (left), and anti-crosstalk light control structures can be configured in the non-filtered areas of multiple adjacent boundaries of each sub-pixel (right).

[0046] In another embodiment, the color filter subpixels are arranged in an interleaved manner, with the subpixels exhibiting a periodic interleaved distribution in both the horizontal and vertical directions. With this arrangement, a high-reflectivity layer can be placed at the horizontal and vertical adjacent boundaries of each subpixel, along with a black high-absorption layer to define the subpixel edges. Compared to a striped arrangement, in this embodiment, the reflective layer and the black high-absorption layer can be simultaneously configured in multiple directions to regulate and redirect reflected light from different directions.

[0047] Figure 10 As shown, the color filter subpixels are arranged in an interleaved manner (left). A reflective layer or a black high-absorption layer can be set at the horizontal and vertical adjacent boundaries of each subpixel to define the subpixel edge (right).

[0048] By designing the non-filtering area according to the arrangement of different color filter structures, this invention allows the configuration of the anti-crosstalk light control structure to be neither fixed nor uniform, but rather directional and regional, based on the optical behavior of the display architecture. This design reduces unnecessary light energy loss, increases the proportion of reflected light entering the effective color filter sub-pixels, and improves color saturation without compromising the paper-like characteristics of the electrophoretic reflective display.

[0049] In the above embodiments, the projection area of ​​the anti-crosstalk light control structure on the plane where the color filter structure is located accounts for 1% to 45% of the total area of ​​all color filter sub-pixels, which is adjusted according to factors such as pixel size, color filter structure thickness, and light emission angle of the front light guide plate.

[0050] Obviously, the described embodiments are only a portion, not all, of the embodiments of this application. Without conflict, the embodiments and features described and illustrated herein can be combined with each other. The components of the embodiments of this application generally described and illustrated in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the detailed description of the embodiments of this application is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

Claims

1. An electrophoretic reflective display, comprising an electrophoretic display layer and a color filter structure disposed above the electrophoretic display layer, the color filter structure comprising a plurality of color filter sub-pixels and non-filtering regions located between adjacent color filter sub-pixels, characterized in that: It also includes an anti-crosstalk optical control structure, which is used to reduce optical crosstalk between two adjacent color filter sub-pixels.

2. The electrophoretic reflective display according to claim 1, characterized in that: The anti-crosstalk light control structure includes a barrier wall disposed in the electrophoretic display layer and corresponding to each non-filtering area. The barrier wall is made of a high-reflectivity material or a high-absorption material.

3. The electrophoretic reflective display according to claim 1, characterized in that: An optical adhesive layer is provided between the electrophoretic display layer and the color filter structure. A high-reflection layer or a high-absorption layer is filled on the optical adhesive layer at the positions corresponding to each non-filter area to form the anti-crosstalk light control structure.

4. The electrophoretic reflective display according to claim 1, characterized in that: The anti-crosstalk light control structure includes a high light-absorbing layer filled in the non-filtering area, and a high light-absorbing protrusion structure or a high light-reflecting protrusion structure combined below the high light-absorbing layer.

5. An electrophoretic reflective display according to claim 4, characterized in that: The thickness of the high light-absorbing layer is 0.01 micrometers to 5 micrometers, and the height of the high light-absorbing protrusion structure or the high light-reflecting protrusion structure is 0.5 micrometers to 40 micrometers.

6. The electrophoretic reflective display according to claim 1, characterized in that: The anti-crosstalk light control structure includes a high light-absorbing layer filling the non-filtering area, a high-reflection layer superimposed below the high light-absorbing layer, and a high light-absorbing protrusion structure or a high light-reflection protrusion structure combined below the high-reflection layer.

7. An electrophoretic reflective display according to claim 6, characterized in that: The thickness of the high light-absorbing layer and the high light-reflecting layer is 0.01 micrometers to 5 micrometers, and the height of the high light-absorbing protrusion structure or the high light-reflecting protrusion structure is 0.5 micrometers to 40 micrometers.

8. An electrophoretic reflective display according to claim 4 or 5, characterized in that: The high light-absorbing protrusion structure and the high light-reflecting protrusion structure are circular columnar, square columnar, trapezoidal columnar, or pyramidal.

9. An electrophoretic reflective display according to claim 1, characterized in that: The color filter sub-pixels are arranged in a striped, triangular, or staggered pattern.

10. An electrophoretic reflective display according to claim 1, characterized in that: The projection area of ​​the anti-crosstalk optical control structure on the plane where the color filter structure is located accounts for 1% to 45% of the total area of ​​all color filter sub-pixels.

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