Reflective display device and driving method

Abstract

The application discloses a reflective display device and a driving method. The reflective display device comprises a liquid crystal box and an electronic ink screen which are arranged in a laminated mode. The liquid crystal box comprises a first opposed substrate, a first array substrate and a dye liquid crystal layer. The first array substrate is provided with a Bragg reflection layer corresponding to at least one of a first sub-pixel, a second sub-pixel and a third sub-pixel. The electronic ink screen comprises a second opposed substrate, a second array substrate and ink capsules. All the ink capsules are provided with first color ink particles and second color ink particles with opposite polarities. Through the cooperation of the dye liquid crystal, the Bragg reflection layer and the electronic ink screen, the reflective display device can realize single-color picture display, full-color picture display and double-sided display. The double-box structure is adopted, and the thickness, driving power consumption and manufacturing cost are reduced compared with the three-box structure, and the product competitiveness is improved.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to a reflective display device and driving method. Background Technology

[0002] Display panels offer advantages such as thinness, durability, and low power consumption, which are energy-efficient and environmentally friendly. However, they require a backlight, resulting in a thicker module and higher cost. Electronic paper displays (reflective displays) have emerged as a solution to meet the needs of the general public. Unlike LCD displays, which require a backlight, electronic paper displays can use external light sources to display images. Therefore, even in strong sunlight, the information on the electronic paper remains clearly visible without viewing angle issues. Furthermore, due to their energy efficiency, high reflectivity, and high contrast ratio, electronic paper displays are now widely used in e-readers (such as e-books and e-newspapers) and other electronic components (such as price tags).

[0003] Existing electronic paper displays typically employ E-Ink microcapsule technology (microcapsule electronic ink technology), SiPix microcup technology (microcup electrophoretic display technology), Bridgestone electronic liquid powder technology, cholesteric liquid crystal display (CLCD) technology, microelectromechanical systems (MEMS) technology, or electrowetting technology. However, existing electronic paper display technologies are less mature than liquid crystal display technologies, have lower mass production efficiency, higher manufacturing costs, and can only achieve black and white or single-color displays.

[0004] Existing reflective display devices using cholesteric liquid crystals (CLCs) suffer from limitations due to the pitch requirements of CLCs. A single-pitch CLC can only reflect one color while transmitting other colors. Therefore, single-layer CLC reflective display devices typically display text in yellow on a black background, black on a yellow background, black on a red background, or red on a black background, unable to achieve white text on a black background or black text on a white background like in a book. This significantly limits their application. Furthermore, the color quality of the reflected light from CLCs is poor, affecting the display effect. To achieve white or color display, reflective display devices require a three-layer CLC cell, reflecting red, green, and blue light separately. However, three-layer CLC cells are not only thicker and consume more power, but also have a more complex manufacturing process and higher cost. Summary of the Invention

[0005] In order to overcome the shortcomings and deficiencies of the existing technology, the purpose of this invention is to provide a reflective display device and driving method to solve the problem that electronic paper displays in the prior art can only achieve a single color or have a relatively thick box thickness.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] The present invention provides a reflective display device, comprising a liquid crystal cell and an electronic ink screen stacked on top of each other, wherein the liquid crystal cell is close to a first surface of the reflective display device and the electronic ink screen is close to a second surface of the reflective display device;

[0008] The liquid crystal cell includes a first opposing substrate, a first array substrate disposed opposite to the first opposing substrate, and a dye liquid crystal layer located between the first opposing substrate and the first array substrate. The liquid crystal cell has a plurality of first pixel units arranged in an array. Each of the plurality of first pixel units has a first sub-pixel, a second sub-pixel, and a third sub-pixel. The first array substrate is provided with a first pixel electrode and a Bragg reflection layer. At least one of the first sub-pixel, the second sub-pixel, and the third sub-pixel corresponds to the Bragg reflection layer. The first opposing substrate is provided with a first common electrode that cooperates with the first pixel electrode.

[0009] The electronic ink screen includes a second opposing substrate, a second array substrate disposed opposite to the second opposing substrate, and an ink capsule located between the second opposing substrate and the second array substrate. All the ink capsules contain first color ink particles and second color ink particles of opposite polarity. The second array substrate is provided with a second pixel electrode, and the second opposing substrate is provided with a second common electrode that cooperates with the second pixel electrode.

[0010] Furthermore, the Bragg reflector layer includes a long-pass filter and a short-pass filter. The long-pass filter corresponds to the first sub-pixel, and the short-pass filter corresponds to the second sub-pixel and the third sub-pixel. The long-pass filter can transmit red and green light and reflect blue light, while the short-pass filter can transmit blue light and reflect red and green light.

[0011] Furthermore, the first color ink particle is one of black ink particles, white ink particles, red ink particles, green ink particles, and blue ink particles, and the second color ink particle is one of black ink particles, white ink particles, red ink particles, green ink particles, and blue ink particles, and the first color ink particle and the second color ink particle are ink particles of different colors.

[0012] Furthermore, the first opposing substrate has a blue light gap layer in the region corresponding to the first sub-pixel, and / or a green light gap layer in the region corresponding to the second sub-pixel, and / or a red light gap layer in the region corresponding to the third sub-pixel.

[0013] Furthermore, the electronic ink screen has a plurality of second pixel units arranged in an array, and the first pixel unit corresponds one-to-one with the second pixel unit.

[0014] Furthermore, the first opposing substrate and the first array substrate are both in a fully transparent state in the area corresponding to the first sub-pixel. One of the first color ink particles and the second color ink particles is a black ink particle, and the other is a blue ink particle. The Bragg reflection layer includes a short-pass filter, which corresponds to the second sub-pixel and the third sub-pixel. The short-pass filter can transmit blue light and reflect red and green light.

[0015] Alternatively, both the first opposing substrate and the first array substrate are fully transparent in the region corresponding to the second sub-pixel. One of the first color ink particles and the second color ink particles is a black ink particle, and the other is a green ink particle. The Bragg reflection layer includes a long-pass filter and a short-pass filter. The long-pass filter corresponds to the first sub-pixel, and the short-pass filter corresponds to the third sub-pixel. The long-pass filter can transmit red and green light and reflect blue light, and the short-pass filter can transmit blue light and reflect red and green light.

[0016] Alternatively, both the first opposing substrate and the first array substrate are fully transparent in the region corresponding to the third sub-pixel. One of the first color ink particles and the second color ink particles is a black ink particle, and the other is a red ink particle. The Bragg reflection layer includes a long-pass filter and a short-pass filter. The long-pass filter corresponds to the first sub-pixel, and the short-pass filter corresponds to the second sub-pixel. The long-pass filter can transmit red and green light and reflect blue light, and the short-pass filter can transmit blue light and reflect red and green light.

[0017] Furthermore, the first opposing substrate and the first array substrate are both fully transparent in the areas corresponding to the first sub-pixel and the second sub-pixel. One of the first color ink particles and the second color ink particles is a green ink particle, and the other is a blue ink particle. The Bragg reflection layer includes a short-pass filter, which corresponds to the third sub-pixel. The short-pass filter can transmit blue light and reflect red and green light.

[0018] Alternatively, the first opposing substrate and the first array substrate are both fully transparent in the areas corresponding to the first sub-pixel and the third sub-pixel, one of the first color ink particles and the second color ink particles is a red ink particle and the other is a blue ink particle, the Bragg reflection layer includes a short-pass filter, the short-pass filter corresponds to the second sub-pixel, and the short-pass filter can transmit blue light and reflect red and green light;

[0019] Alternatively, the first opposing substrate and the first array substrate are both in a fully transparent state in the areas corresponding to the second sub-pixel and the third sub-pixel, one of the first color ink particles and the second color ink particles is a red ink particle and the other is a green ink particle, the Bragg reflection layer includes a long-pass filter, the long-pass filter corresponds to the first sub-pixel, and the long-pass filter can transmit red and green light and reflect blue light.

[0020] This application also provides a driving method for a reflective display device, used to drive the reflective display device as described above, the driving method comprising:

[0021] When displaying a dual-color image on the second side alone, the control LCD cell is turned off and the e-ink screen is turned on, with the e-ink screen facing the second side to display the dual-color image;

[0022] When the first side displays a full-color image and the second side displays a dual-color image, both the liquid crystal display (LCD) and the e-ink display are turned on. The LCD displays a full-color image facing the first side, and the e-ink display displays a dual-color image facing the second side.

[0023] Furthermore, the Bragg reflector layer includes a long-pass filter and a short-pass filter. The long-pass filter corresponds to the first sub-pixel, and the short-pass filter corresponds to the second sub-pixel and the third sub-pixel. The long-pass filter can transmit red and green light and reflect blue light, and the short-pass filter can transmit blue light and reflect red and green light. One of the first color ink particles and the second color ink particles is a black ink particle. The driving method includes:

[0024] When displaying a full-color image on the first side alone, the liquid crystal cell is controlled to turn on and off the e-ink screen. All black ink particles in the ink capsules of the e-ink screen are oriented towards the liquid crystal cell, and the liquid crystal cell is oriented towards the first side to display a full-color image.

[0025] Furthermore, the Bragg reflector layer includes a long-pass filter and a short-pass filter. The long-pass filter corresponds to the first sub-pixel, and the short-pass filter corresponds to the second sub-pixel and the third sub-pixel. The long-pass filter can transmit red and green light and reflect blue light, and the short-pass filter can transmit blue light and reflect red and green light. The first opposing substrate has a blue light gap layer in the region corresponding to the first sub-pixel, a green light gap layer in the region corresponding to the second sub-pixel, and a red light gap layer in the region corresponding to the third sub-pixel. The driving method includes:

[0026] When displaying a full-color image on the first side alone, the LCD cell is controlled to turn on and off the e-ink screen, and the LCD cell faces the first side to display a full-color image.

[0027] The beneficial effects of this invention are as follows: through the cooperation of dye liquid crystal, Bragg reflective layer and electronic ink screen, the reflective display device can not only realize single color screen display, but also full color screen display and double-sided display. Moreover, it only requires a two-cell structure, which reduces thickness, driving power consumption and manufacturing cost compared with a three-cell structure, thereby enhancing product competitiveness. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the reflective display device in its initial state according to Embodiment 1 of the present invention;

[0029] Figure 2 This is a schematic diagram of the planar structure of the first array substrate in Embodiment 1 of the present invention;

[0030] Figure 3 This is a schematic diagram of the planar structure of the second array substrate in Embodiment 1 of the present invention;

[0031] Figure 4 This is a transmittance curve of the long-pass filter and short-pass filter for different light rays in Embodiment 1 of the present invention;

[0032] Figure 5 This is a graph showing the reflectance of the short-pass filter for light rays at different incident angles in Embodiment 1 of the present invention.

[0033] Figure 6 This is a graph showing the reflectivity of the long-pass filter for light rays at different incident angles in Embodiment 1 of the present invention.

[0034] Figure 7 This is a schematic diagram of the reflective display device in the black state according to Embodiment 1 of the present invention;

[0035] Figure 8 This is a schematic diagram of the structure of the reflective display device in Embodiment 1 of the present invention when displaying a black and white image on the second surface;

[0036] Figure 9 This is a schematic diagram of the structure of the reflective display device in Embodiment 1 of the present invention when the first surface displays a white state;

[0037] Figure 10 This is a schematic diagram of the optical path analysis of the reflective display device in Embodiment 1 of the present invention when the first surface displays a white state;

[0038] Figure 11 This is a schematic diagram of the structure of the reflective display device in Embodiment 1 of the present invention when displaying a full-color image on the first surface;

[0039] Figure 12 This is a schematic diagram of the optical path analysis when the reflective display device displays a full-color image on the first surface in Embodiment 1 of the present invention;

[0040] Figure 13 This is a schematic diagram of the structure of the reflective display device in Embodiment 2 of the present invention when the first side displays a full-color image and the second side displays a dual-color image;

[0041] Figure 14 This is a schematic diagram of the optical path analysis of the reflective display device in Embodiment 2 of the present invention when the first side displays a full-color image and the second side displays a dual-color image;

[0042] Figure 15 This is a schematic diagram of the structure of the reflective display device in Embodiment 3 of the present invention when the first side displays a full-color image and the second side displays a dual-color image;

[0043] Figure 16 This is a schematic diagram of the optical path analysis of the reflective display device in Embodiment 3 of the present invention when the first side displays a full-color image and the second side displays a dual-color image;

[0044] Figure 17 This is a schematic diagram of the structure of the reflective display device in Embodiment 4 of the present invention when the first side displays a full-color image and the second side displays a dual-color image;

[0045] Figure 18 This is a schematic diagram of the optical path analysis of the reflective display device in Embodiment 4 of the present invention when the first side displays a full-color image and the second side displays a dual-color image;

[0046] Figure 19 This is a schematic diagram of the structure of the reflective display device in Embodiment 5 of the present invention when the first side displays a full-color image and the second side displays a dual-color image;

[0047] Figure 20 This is a schematic diagram of the optical path analysis of the reflective display device in Embodiment 5 of the present invention when the first side displays a full-color image and the second side displays a dual-color image. Detailed Implementation

[0048] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following detailed description, in conjunction with the accompanying drawings and preferred embodiments, provides a detailed explanation of the specific implementation methods, structures, features, and effects of the reflective display device and driving method proposed according to the present invention:

[0049] [Example 1]

[0050] Figure 1 This is a schematic diagram of the reflective display device in its initial state according to Embodiment 1 of the present invention. Figure 2 This is a schematic diagram of the planar structure of the first array substrate in Embodiment 1 of the present invention. Figure 3 This is a schematic diagram of the planar structure of the second array substrate in Embodiment 1 of the present invention.

[0051] like Figures 1 to 3 As shown, a reflective display device provided in Embodiment 1 of the present invention includes a liquid crystal cell 10 and an electronic ink screen 20 stacked on top of each other. The liquid crystal cell 10 is close to the first side of the reflective display device, and the electronic ink screen 20 is close to the second side of the reflective display device. For example, the first side is the upper side of the reflective display device, and the second side is the lower side of the reflective display device.

[0052] The liquid crystal cell 10 includes a first opposing substrate 11, a first array substrate 12 disposed opposite to the first opposing substrate 11, and a dye-based liquid crystal layer 13 located between the first opposing substrate 11 and the first array substrate 12. The first opposing substrate 11 is close to a first surface of the liquid crystal cell 10, and the first array substrate 12 is close to a second surface of the liquid crystal cell 10. The liquid crystal cell 10 has a plurality of first pixel units P1 arranged in an array. The plurality of first pixel units P1 have a first sub-pixel SP1, a second sub-pixel SP2, and a third sub-pixel SP3. The first array substrate 12 is provided with a first pixel electrode 121 and a Bragg reflective layer. At least one of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 corresponds to the Bragg reflective layer. The first opposing substrate 11 is provided with a first common electrode 111 that cooperates with the first pixel electrode 121. The first common electrode 111 is a planar electrode that covers the entire surface of the first opposing substrate 11. The first pixel electrode 121 is a block electrode that corresponds one-to-one with the first pixel unit P1.

[0053] The dye-based liquid crystal layer 13 comprises mixed liquid crystal molecules 131 and dye molecules 132, meaning that the dye-based liquid crystal layer 13 is doped with dye molecules 132. The liquid crystal molecules 131 in the dye-based liquid crystal layer 13 are positive liquid crystal molecules (liquid crystal molecules with positive dielectric anisotropy), such as... Figure 1As shown, in the initial state, liquid crystal molecules 131 and dye molecules 132 are aligned parallel to the first opposing substrate 11 and the first array substrate 12. The alignment direction of the dye liquid crystal layer 13 near the first opposing substrate 11 is perpendicular to the alignment direction near the first array substrate 12. That is, the liquid crystal molecules 131 and dye molecules 132 in the dye liquid crystal layer 13 are twisted 90° from bottom to top to form a TN display mode. The light absorption capacity of the dye molecules 132 along their long axis is greater than that along their short axis. Dye molecules 132 have a strong ability to absorb light along their long axis and a very weak ability to absorb light along their short axis. Therefore, no additional polarizers are needed on both sides of the liquid crystal cell to control the grayscale brightness. Because the liquid crystal molecules 131 and dye molecules 132 in the dye liquid crystal layer 13 are twisted 90° from bottom to top, the liquid crystal cell in this embodiment is in a closed state, i.e., a dark state, in the initial state.

[0054] like Figure 2 As shown, the first array substrate 12 is provided with multiple first scan lines 101, multiple first data lines 102, and multiple first thin-film transistors 103. The first array substrate 12 provides a first pixel electrode 121 and a first thin-film transistor 103 in the region corresponding to each first pixel unit P1. The first pixel electrode 121 is electrically connected to the first scan line 101 and the first data line 102 adjacent to the first thin-film transistor 103 through the first thin-film transistor 103. The first thin-film transistor 103 includes a first gate, a first active layer, a first drain, and a first source. The first gate and the first scan line 101 are located on the same layer and electrically connected. The first gate and the first active layer are isolated by an insulating layer. The first source is electrically connected to the first data line 102, and the first drain is electrically connected to the first pixel electrode 121 through a contact hole.

[0055] In this embodiment, the Bragg reflector layer includes a long-pass filter 141 and a short-pass filter 142. The long-pass filter 141 corresponds to the first sub-pixel SP1, and the short-pass filter 142 corresponds to the second sub-pixel SP2 and the third sub-pixel SP3. The long-pass filter 141 can transmit red and green light and reflect blue light, while the short-pass filter 142 can transmit blue light and reflect red and green light. That is, the first sub-pixel SP1 can reflect blue light alone, while the second sub-pixel SP2 and the third sub-pixel SP3 can both reflect red and green light (yellow light). Optionally, the area ratio of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 is 1:0.5:0.5, so that the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 can mix to produce white light.

[0056] Both the long-pass filter 141 (Short-pass filter, SPF) and the short-pass filter 142 (Long-pass filter, LPF) are distributed Bragg reflectors (DBRs). The short-pass filter 142 transmits blue light with wavelengths below 490 nm and reflects red and green light with wavelengths between 500 and 680 nm, while the long-pass filter 141 transmits red and green light with wavelengths between 500 and 680 nm and reflects blue light with wavelengths below 490 nm. Distributed Bragg reflectors (DBRs) are reflectors used in waveguides. The long-pass filter 141 and the short-pass filter 142 use SiO2 (silicon dioxide) and TiO2 (titanium dioxide) as alternating materials, achieving two different bandpasses through adjustment of the film thickness and logarithm. When light passes through different media, it is reflected at the interface. The reflectivity is related to the refractive indices of the media. Therefore, if we periodically stack thin films with different refractive indices, when light passes through these films, the reflected light from each layer undergoes constructive interference due to the change in phase angle, and then combines with each other to produce strongly reflected light. If the number of layers becomes very large, and the difference in refractive indices n1, n2, n3, etc., becomes very small, the light travels as if it were in a single medium, and the reflection coefficient becomes very small. The interference effect caused by the multiple interferences of light is very significant, making it very sensitive to wavelength selection. When using a grating-like structure, this periodic structure is called a distributed Bragg reflector.

[0057] Figure 4 This is a transmittance curve diagram of the long-pass filter and short-pass filter for different light rays in Embodiment 1 of the present invention, as shown below. Figure 4 As shown in the figure, curves R, G, and B represent the wavelengths of red, green, and blue light, respectively, and curves L and S represent the transmittance of long-pass filter 141 and short-pass filter 142 for different wavelengths of light, respectively. Figure 4 It can be seen that the long-pass filter 141 has a good transmission effect on blue light with wavelengths below 490nm, and the transmittance can reach more than 95%; while the short-pass filter 142 has a good transmission effect on red and green light with wavelengths between 500 and 680nm, and the transmittance can reach more than 95%.

[0058] Figure 5 This is a graph showing the reflectance of the short-pass filter for light rays at different incident angles in Embodiment 1 of the present invention. Figure 6 This is a reflection curve of the long-pass filter for light rays at different incident angles in Embodiment 1 of the present invention, as shown in the figure. Figure 5 and Figure 6As shown, curves S1, S2, S3, and S4 represent the reflectivity of short-pass filter 142 for white light with incident angles of 0°, 20°, 40°, and 60°, respectively, while curves L1, L2, L3, and L4 represent the reflectivity of long-pass filter 141 for white light with incident angles of 0°, 20°, 40°, and 60°, respectively. Figure 5 and Figure 6 It can be seen that when the incident light angle is less than 40°, the short-pass filter 142 has a reflectivity of up to 98% for red and green light in the range of 490-700nm, which helps to reflect and utilize red and green light. At the same time, the long-pass filter 141 also has a reflectivity of 94% for blue light in the range of 400-500nm, which reduces the emissivity of blue light and improves the reflection and utilization of blue light.

[0059] Furthermore, a black matrix 112 is also provided on the first opposing substrate 11. The black matrix 112 is used to separate the multiple first pixel units P1 from each other, thereby avoiding the problem of light leakage or color mixing between the multiple first pixel units P1. In this embodiment, the areas of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 of the first opposing substrate 11 are in a completely transparent state (that is, light can completely pass through the first opposing substrate 11, and there is basically no reflection or absorption of light). The areas of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 of the first opposing substrate 11 are covered by a planarization layer (OC material).

[0060] The e-ink screen 20 includes a second opposing substrate 21, a second array substrate 22 disposed opposite to the second opposing substrate 21, and ink capsules 23 located between the second opposing substrate 21 and the second array substrate 22. The second opposing substrate 21 is close to a first surface of the e-ink screen 20, and the second array substrate 22 is close to a second surface of the e-ink screen 20. Each ink capsule 23 contains first-color ink particles 231 and second-color ink particles 232 of opposite polarities and different colors. The e-ink screen 20 has a plurality of second pixel units P2 arranged in an array, and each second pixel unit P2 contains an ink capsule 23. By providing electric fields in different directions to the ink capsules 23, the first-color ink particles 231 and second-color ink particles 232 can move in corresponding directions. In this embodiment, the first-color ink particles 231 are negatively charged, and the second-color ink particles 232 are positively charged, causing the second-color ink particles 232 to move in the direction of the electric field, and the first-color ink particles 231 to move in the opposite direction of the electric field. If an upward-facing electric field is provided, the second-color ink particle 232 moves upward, and the first-color ink particle 231 moves downward; if a downward-facing electric field is provided, the second-color ink particle 232 moves downward, and the first-color ink particle 231 moves upward. Alternatively, in other embodiments, the first-color ink particle 231 may be positively charged, and the second-color ink particle 232 negatively charged, causing the first-color ink particle 231 to move in the direction of the electric field, and the second-color ink particle 232 to move in the opposite direction of the electric field. If an upward-facing electric field is provided, the second-color ink particle 232 moves downward, and the first-color ink particle 231 moves upward; if a downward-facing electric field is provided, the second-color ink particle 232 moves upward, and the first-color ink particle 231 moves downward.

[0061] The second array substrate 22 is provided with a second pixel electrode 221, which corresponds one-to-one with the second pixel unit P2. The second opposing substrate 21 is provided with a second common electrode 211 that cooperates with the second pixel electrode 221. The second pixel electrode 221 is a block electrode corresponding to the second pixel unit P2, and the second common electrode 211 is a planar electrode that covers the entire surface of the second opposing substrate 21. The direction of the electric field between the second pixel electrode 221 and the second common electrode 211 is controlled by controlling the voltage polarity on the second pixel electrode 221. For example, if a negative voltage (e.g., -10 to -20V) is applied to the second common electrode 211, and a positive voltage (e.g., +10 to +20V) is applied to the second pixel electrode 221, the electric field between the second pixel electrode 221 and the second common electrode 211 is directed upwards, and the first color ink particles 231 move toward the second pixel electrode 221, while the second color ink particles 232 move toward the second common electrode 211. If a positive voltage (e.g., +10 to +20V) is applied to the second common electrode 211, and a negative voltage (e.g., -10 to -20V) is applied to the second pixel electrode 221, the electric field between the second pixel electrode 221 and the second common electrode 211 is directed downwards, and the first color ink particles 231 move toward the second common electrode 211, while the second color ink particles 232 move toward the second pixel electrode 221.

[0062] In this embodiment, the first pixel unit P1 and the second pixel unit P2 correspond one-to-one, thereby facilitating control of the display screen in a dual-sided display (i.e., one side displays a dual-color image, and the other side displays a full-color image). Of course, in other embodiments, one first pixel unit P1 can correspond to multiple second pixel units P2, or multiple first pixel units P1 can correspond to one second pixel unit P.

[0063] like Figure 3 As shown, the second array substrate 22 is provided with multiple second scan lines 201, multiple second data lines 202, and multiple second thin-film transistors 203. The second array substrate 22 provides a second pixel electrode 221 and a second thin-film transistor 203 in the region corresponding to each second pixel unit P2. The second pixel electrode 221 is electrically connected to the second scan line 201 and the second data line 202 adjacent to the second thin-film transistor 203 through the second thin-film transistor 203. The second thin-film transistor 203 includes a second gate, a second active layer, a second drain, and a second source. The second gate and the second scan line 201 are located on the same layer and electrically connected. The second gate and the second active layer are isolated by an insulating layer. The second source is electrically connected to the second data line 202, and the second drain is electrically connected to the second pixel electrode 221 through a contact hole.

[0064] The first opposing substrate 11, the first array substrate 12, the second opposing substrate 21, and the second array substrate 22 can be made of transparent substrates such as glass, acrylic, and polycarbonate. The first common electrode 111, the first pixel electrode 121, the second common electrode 221, and the second pixel electrode 221 can be made of transparent electrodes such as indium tin oxide (ITO) or indium zinc oxide (IZO). Alternatively, in other embodiments, the second array substrate 22 can be made of a non-transparent substrate or coated with black ink, so that the reflective display device can only display a full-color image on the first side, and not display an image on the second side, which will be pure black.

[0065] Furthermore, the first color ink particle 231 is one of black ink particles, white ink particles, red ink particles, green ink particles, and blue ink particles, and the second color ink particle 232 is one of black ink particles, white ink particles, red ink particles, green ink particles, and blue ink particles. The first color ink particle 231 and the second color ink particle 232 are ink particles of different colors. In this embodiment, the first color ink particle 231 is a black ink particle, and the second color ink particle 232 is a white ink particle. Using white ink particles allows a single first pixel unit P1 to achieve white reflection, while using black ink particles results in purer colors when displaying a full-color image. Of course, in other embodiments, the first color ink particle 231 can also be one of red ink particles, green ink particles, and blue ink particles, and the second color ink particle 232 can also be one of red ink particles, green ink particles, and blue ink particles, thereby selecting the colors of the first color ink particle 231 and the second color ink particle 232 according to the color requirements of displaying a full-color image on the first side and displaying a dual-color image on the second side.

[0066] This embodiment also provides a driving method for driving the reflective display panel described above. The following description uses an example where the first color ink particles 231 are negatively charged and the second color ink particles 232 are positively charged. The driving method includes:

[0067] Figure 7 This is a schematic diagram of the reflective display device in the black state according to Embodiment 1 of the present invention. Figure 7 As shown, both the liquid crystal cell 10 and the electronic ink screen 20 are controlled to be in the off state. For example, the first color ink particle 231 (black ink particle) can be controlled to approach the second array substrate 22 and then the electronic ink screen 20 can be turned off, so that the reflective display device is in a pure black state on both the first and second surfaces.

[0068] Figure 8This is a schematic diagram of the structure of the reflective display device in Embodiment 1 of the present invention when displaying a black and white image on the second surface. Figure 8 As shown, when displaying a dual-color image on the second side alone, the control LCD cell 10 is turned off and the e-ink screen 20 is turned on, with the e-ink screen 20 facing the second side to display the dual-color image. For the second pixel unit P2 of the e-ink screen 20 displaying the first color (black) on the second side, a negative voltage (e.g., -10 to -20V) is applied to the second common electrode 211, and a positive voltage (e.g., +10 to +20V) is applied to the second pixel electrode 221. The electric field direction between the second pixel electrode 221 and the second common electrode 211 is upward. The first color ink particles 231 move downward and concentrate near the second pixel electrode 221, while the second color ink particles 232 move upward and concentrate near the second common electrode 211. The black ink particles absorb the light incident from the second side, thus displaying black. For the second pixel unit P2 of the e-ink screen 20 that displays the second color (white) facing the second surface, a positive voltage (e.g., +10 to +20V) is applied to the second common electrode 211, and a negative voltage (e.g., -10 to -20V) is applied to the second pixel electrode 221. The electric field between the second pixel electrode 221 and the second common electrode 211 is directed downwards. Consequently, the second-color ink particles 232 move downwards and concentrate near the second pixel electrode 221, while the first-color ink particles 231 move upwards and concentrate near the second common electrode 211. The white ink particles reflect the light incident from the second surface, thus displaying white. The combination of the black and white second pixel units P2 enables the reflective display device to display a dual-color image (black and white image) facing the second surface.

[0069] Figure 9 This is a schematic diagram of the structure of the reflective display device in Embodiment 1 of the present invention when the first surface displays a white state. Figure 10 This is a schematic diagram of the optical path analysis of the reflective display device in Embodiment 1 of the present invention when the first surface displays a white state. Figure 9 and Figure 10 As shown, when the first surface displays a white state, the liquid crystal cell 10 is controlled to turn the e-ink screen 20 on and off. For example, the first color ink particles 231 (black ink particles) can be controlled to approach the second array substrate 22 before the e-ink screen 20 is turned off, thus making the reflective display device a pure black state on the second surface. Light incident on the first surface passes through the long-pass filter 141, transmitting red and green light and reflecting blue light, while the red and green light is reflected back by the white ink particles; while light incident on the first surface passes through the short-pass filter 14, transmitting blue light and reflecting red and green light, while the blue light is reflected back by the white ink particles, thus allowing a single first pixel unit P1 to display white.

[0070] Figure 11 This is a schematic diagram of the structure of the reflective display device in Embodiment 1 of the present invention when displaying a full-color image on the first surface. Figure 12 This is a schematic diagram of the optical path analysis when the reflective display device displays a full-color image on the first surface in Embodiment 1 of the present invention. Figure 11 and Figure 12 As shown, when the first surface displays a full-color image, the control unit 10 turns the e-ink screen 20 on and off, with the liquid crystal cell 10 facing the first surface to display the full-color image. All black ink particles in the ink capsules 23 of the e-ink screen 20 face the liquid crystal cell 10. For example, the first color ink particles 231 (black ink particles) can be controlled to approach the second opposing substrate 21 before the e-ink screen 20 is turned off, thus making the reflective display device pure white on the second surface. Light incident on the first surface passes through the long-pass filter 141, transmitting red and green light and reflecting blue light. The red and green light is absorbed by the black ink particles, causing the first sub-pixel SP1 to display blue. Light incident on the first surface passes through the short-pass filter 14, transmitting blue light and reflecting red and green light. The blue light is absorbed by the black ink particles, causing the second sub-pixel SP2 and the third sub-pixel SP3 to display red and green (yellow). By controlling the grayscale brightness of the first sub-pixel SP1 (displaying blue) and the grayscale brightness of the second sub-pixel SP2 and the third sub-pixel SP3 (displaying red and green) through the dye liquid crystal layer 13, the first surface of the reflective display device can display a full-color image.

[0071] When the first side displays a full-color image and the second side displays a dual-color image, both the control LCD box 10 and the e-ink screen 20 are turned on. The LCD box 10 faces the first side to display the full-color image, and the e-ink screen 20 faces the second side to display the dual-color image. With the cooperation of the e-ink screen 20, the LCD box 10 can achieve a wider color gamut for the full-color image displayed on the first side, but the patterns of the full-color image on the first side and the dual-color image on the second side will interfere with each other.

[0072] [Example 2]

[0073] Figure 13 This is a schematic diagram of the structure of the reflective display device in Embodiment 2 of the present invention, showing a full-color image on the first side and a dual-color image on the second side. Figure 14 This is a schematic diagram of the optical path analysis of the reflective display device in Embodiment 2 of the present invention when displaying a full-color image on the first surface and a dual-color image on the second surface. For example... Figure 13 and Figure 14 As shown, the reflective display device and driving method provided in Embodiment 2 of the present invention are the same as those in Embodiment 1. Figures 1 to 12 The reflective display device and driving method in this embodiment are basically the same, except that in this embodiment:

[0074] The first opposing substrate 11 and the first array substrate 12 are both in a fully transparent state in the region corresponding to one of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3. At least one of the first color ink particles 231 and the second color ink particles 232 is an ink particle of the color corresponding to the fully transparent sub-pixel. In this embodiment, the first opposing substrate 11 and the first array substrate 12 are both in a fully transparent state in the region corresponding to the third sub-pixel SP3 (i.e., light can completely pass through the first opposing substrate 11 and the first array substrate 12, with virtually no reflection or absorption of light). The first opposing substrate 11 and the first array substrate 12 do not have Bragg reflectors or filter gap layers in the region corresponding to the third sub-pixel SP3. One of the first color ink particles 231 and the second color ink particles 232 is a black ink particle, and the other is a red ink particle. In this embodiment, the first color ink particle 231 is a black ink particle, and the second color ink particle 232 is a red ink particle. The red ink particle can reflect red light and absorb other colors of light. This allows the red light reflected by the red ink particles to provide reflected light for the third sub-pixel SP3 on the first surface, enabling the third sub-pixel SP3 to display red independently. Furthermore, the red ink particles reflect red light with better color saturation, which can improve the display quality.

[0075] The Bragg reflector layer includes a long-pass filter 141 and a short-pass filter 142. The long-pass filter 141 corresponds to the first sub-pixel SP1, and the short-pass filter 142 corresponds to the second sub-pixel SP2. The long-pass filter 141 transmits red and green light and reflects blue light, while the short-pass filter 142 transmits blue light and reflects red and green light. In the projection direction of the first array substrate 12, the short-pass filter 142 and the third sub-pixel SP3 have no overlapping area.

[0076] Furthermore, the first opposing substrate 11 has a green light gap layer 113g in the area corresponding to the second sub-pixel SP2. The green light gap layer 113g has multiple gaps with a width of 500-570nm. The green light gap layer 113g can transmit green light and absorb red and blue light. That is, when the green light gap layer 113g passes through the first opposing substrate 11, the red and blue light is absorbed, and the incident light on the first surface cannot reach the e-ink screen 20, reducing the impact of the e-ink screen 20 on the full-color display of the first surface. The short-pass filter 142 is only used to reflect green light, thereby providing reflected green light for the display of the second sub-pixel SP2 on the first surface, so that the second sub-pixel SP2 can display green independently. Of course, in other embodiments, the first opposing substrate 11 may also have a blue light gap layer 113b in the area corresponding to the first sub-pixel SP1. The blue light gap layer 113b has multiple gaps with a width of 630 to 780 nm. The blue light gap layer 113b can transmit blue light and absorb red and green light. That is, when the blue light gap layer 113b passes through the first opposing substrate 11, the red and green light is absorbed, and the incident light on the first surface cannot illuminate the electronic ink screen 20.

[0077] The light filtering gap layers (blue light gap layer 113b and green light gap layer 113g) are based on the principle of light interference. By setting light filtering gap layers with different thicknesses and gap widths on the first opposing substrate 11, the light filtering gap layers can be formed by etching using nanoimprint lithography or photolithography. This allows for the filtering of different colors of light, achieving the technical effect of light filtering. The structure is simple and the cost is low.

[0078] like Figure 13 and Figure 14 As shown, when the first side displays a full-color image and the second side displays a dual-color image, both the control LCD cell 10 and the e-ink screen 20 are turned on. The LCD cell 10 faces the first side to display the full-color image, and the e-ink screen 20 faces the second side to display the dual-color image (red and black). In this embodiment, the second sub-pixel SP2 can display green independently, and the third sub-pixel SP3 can display red independently. Compared to Embodiment 1, the color gamut of the first side displaying the full-color image is wider. Moreover, the color displayed by the second sub-pixel SP2 is not affected by the e-ink screen 20, reducing the mutual interference between the patterns of the first side displaying the full-color image and the second side displaying the dual-color image.

[0079] Specifically, for the e-ink screen 20, when a negative voltage (e.g., -10 to -20V) is applied to the second common electrode 211 in the corresponding second pixel unit P2, and a positive voltage (e.g., +10 to +20V) is applied to the second pixel electrode 221, the electric field direction between the second pixel electrode 221 and the second common electrode 211 is upward. As a result, the first color ink particles 231 move downward and concentrate near the second pixel electrode 221, and the second color ink particles 232 move upward and concentrate near the second common electrode 211. If a positive voltage (e.g., +10 to +20V) is applied to the second common electrode 211 in the corresponding second pixel unit P2, and a negative voltage (e.g., -10 to -20V) is applied to the second pixel electrode 221, the electric field between the second pixel electrode 221 and the second common electrode 211 will be directed downwards. Consequently, the second color ink particles 232 will move downwards and concentrate near the second pixel electrode 221, while the first color ink particles 231 will move upwards and concentrate near the second common electrode 211. In other words, the driving method of the electronic ink screen 20 is basically the same as in Embodiment 1, except that the colors selected by the first color ink particles 231 and the second color ink particles 232 are different, i.e., the colors of the reflected light are different.

[0080] Those skilled in the art should understand that the remaining structures and working principles of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0081] [Example 3]

[0082] Figure 15 This is a schematic diagram of the structure of the reflective display device in Embodiment 3 of the present invention, showing a full-color image on the first side and a dual-color image on the second side. Figure 16 This is a schematic diagram of the optical path analysis of the reflective display device in Embodiment 3 of the present invention when displaying a full-color image on the first surface and a dual-color image on the second surface. Figure 15 and Figure 16 As shown, the reflective display device and driving method provided in Embodiment 2 of the present invention are the same as those in Embodiment 1. Figures 1 to 12 The reflective display device and driving method in this embodiment are basically the same, except that in this embodiment:

[0083] The first opposing substrate 11 and the first array substrate 12 are both in a fully transparent state in the region corresponding to one of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3. At least one of the first color ink particle 231 and the second color ink particle 232 is an ink particle of the color corresponding to the fully transparent sub-pixel. In this embodiment, the first opposing substrate 11 and the first array substrate 12 are both in a fully transparent state in the region corresponding to the second sub-pixel SP2 (i.e., light can completely pass through the first opposing substrate 11 and the first array substrate 12, with virtually no reflection or absorption of light). The first opposing substrate 11 and the first array substrate 12 do not have Bragg reflectors or filter gap layers in the region corresponding to the second sub-pixel SP2. One of the first color ink particle 231 and the second color ink particle 232 is a black ink particle, and the other is a green ink particle. In this embodiment, the first color ink particle 231 is a black ink particle, and the second color ink particle 232 is a green ink particle. The green ink particle can reflect green light and absorb light of other colors. This allows the green light reflected by the green ink particles to provide reflected light for the second sub-pixel SP2 on the first surface, enabling the second sub-pixel SP2 to display green independently. Furthermore, the green light reflected by the green ink particles has better color saturation, which can increase the display quality.

[0084] The Bragg reflector layer includes a long-pass filter 141 and a short-pass filter 142. The long-pass filter 141 corresponds to the first sub-pixel SP1, and the short-pass filter 142 corresponds to the third sub-pixel SP3. The long-pass filter 141 transmits red and green light and reflects blue light, while the short-pass filter 142 transmits blue light and reflects red and green light. In the projection direction of the first array substrate 12, the short-pass filter 142 and the second sub-pixel SP2 have no overlapping area.

[0085] Furthermore, the first opposing substrate 11 has a blue light gap layer 113b in the area corresponding to the first sub-pixel SP1 and a red light gap layer 113r in the area corresponding to the third sub-pixel SP3. The blue light gap layer 113b has multiple slits with a width of 630-780nm, allowing blue light to pass through while absorbing red and green light, thus enabling the first sub-pixel SP1 to display blue independently. The red light gap layer 113r has multiple slits with a width of 420-470nm, allowing red light to pass through while absorbing blue and green light, thus enabling the third sub-pixel SP3 to display red independently. In other words, the blue light gap layer 113b and the red light gap layer 113r absorb the red and green light and the blue and green light in the first opposing substrate 11, preventing the incident light from reaching the e-ink screen 20 and reducing the impact of the e-ink screen 20 on the full-color display of the first surface.

[0086] The light filtering gap layers (blue light gap layer 113b and red light gap layer 113r) are based on the principle of light interference. By setting light filtering gap layers with different thicknesses and gap widths on the first opposing substrate 11, the light filtering gap layers can be formed by etching using nanoimprint lithography or photolithography. This allows for the filtering of different colors of light, achieving the technical effect of light filtering. The structure is simple and the cost is low.

[0087] like Figure 15 and Figure 16 As shown, when the first side displays a full-color image and the second side displays a dual-color image, both the control LCD cell 10 and the e-ink screen 20 are turned on. The LCD cell 10 faces the first side to display the full-color image, and the e-ink screen 20 faces the second side to display the dual-color image (green and black). In this embodiment, the second sub-pixel SP2 can display green independently, and the third sub-pixel SP3 can display red independently. Compared to Embodiment 1, the color gamut of the full-color image displayed on the first side is wider. Moreover, the colors displayed by the first sub-pixel SP1 and the third sub-pixel SP3 are not affected by the e-ink screen 20, reducing the mutual interference between the patterns of the full-color image displayed on the first side and the dual-color image displayed on the second side.

[0088] Specifically, for the e-ink screen 20, when a negative voltage (e.g., -10 to -20V) is applied to the second common electrode 211 in the corresponding second pixel unit P2, and a positive voltage (e.g., +10 to +20V) is applied to the second pixel electrode 221, the electric field direction between the second pixel electrode 221 and the second common electrode 211 is upward. As a result, the first color ink particles 231 move downward and concentrate near the second pixel electrode 221, and the second color ink particles 232 move upward and concentrate near the second common electrode 211. If a positive voltage (e.g., +10 to +20V) is applied to the second common electrode 211 in the corresponding second pixel unit P2, and a negative voltage (e.g., -10 to -20V) is applied to the second pixel electrode 221, the electric field between the second pixel electrode 221 and the second common electrode 211 will be directed downwards. Consequently, the second color ink particles 232 will move downwards and concentrate near the second pixel electrode 221, while the first color ink particles 231 will move upwards and concentrate near the second common electrode 211. In other words, the driving method of the electronic ink screen 20 is basically the same as in Embodiment 1, except that the colors selected by the first color ink particles 231 and the second color ink particles 232 are different, i.e., the colors of the reflected light are different.

[0089] In another embodiment, the areas of the first opposing substrate 11 and the first array substrate 12 corresponding to the first sub-pixel SP1 can also be completely transparent (i.e., light can completely pass through the first opposing substrate 11 and the first array substrate 12, with virtually no reflection or absorption of light). Neither the first opposing substrate 11 nor the first array substrate 12 has a Bragg reflector or a filter gap layer in the area corresponding to the first sub-pixel SP1. One of the first color ink particles 231 and the second color ink particles 232 is a black ink particle, and the other is a blue ink particle. The Bragg reflector layer includes a short-pass filter 142, which corresponds to the second sub-pixel SP2 and the third sub-pixel SP3. The short-pass filter 142 can transmit blue light and reflect red and green light. Since the first sub-pixel SP1 achieves color display through the blue light reflected by the blue ink particles, the area corresponding to the first sub-pixel SP1 does not need to have a long-pass filter 141.

[0090] Those skilled in the art should understand that the remaining structures and working principles of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0091] [Example 4]

[0092] Figure 17 This is a schematic diagram of the structure of the reflective display device in Embodiment 4 of the present invention, showing a full-color image on the first side and a dual-color image on the second side. Figure 18 This is a schematic diagram of the optical path analysis of the reflective display device in Embodiment 4 of the present invention when displaying a full-color image on the first side and a dual-color image on the second side. Figure 17 and Figure 18 As shown, the reflective display device and driving method provided in Embodiment 4 of the present invention are the same as those in Embodiment 1. Figures 1 to 12 The reflective display device and driving method in this embodiment are basically the same, except that in this embodiment:

[0093] The first opposing substrate 11 and the first array substrate 12 are both fully transparent in the regions corresponding to two of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3. At least one of the first color ink particle 231 and the second color ink particle 232 is an ink particle of the color corresponding to the fully transparent sub-pixel. In this embodiment, the first opposing substrate 11 and the first array substrate 12 are both fully transparent in the regions corresponding to the second sub-pixel SP2 and the third sub-pixel SP3 (i.e., light can completely pass through the first opposing substrate 11 and the first array substrate 12, with virtually no reflection or absorption of light). Neither the first opposing substrate 11 nor the first array substrate 12 has a Bragg reflector or a filter gap layer in the regions corresponding to the second sub-pixel SP2 and the third sub-pixel SP3. One of the first color ink particle 231 and the second color ink particle 232 is a red ink particle, and the other is a green ink particle. In this embodiment, the first color ink particle 231 is a red ink particle, which can reflect red light and absorb other colors of light; the second color ink particle 232 is a green ink particle, which can reflect green light and absorb other colors of light. Thus, the red light reflected by the red ink particles provides reflected light for the third sub-pixel SP3 on the first surface, allowing the third sub-pixel SP3 to display red independently; and the green light reflected by the green ink particles provides reflected light for the second sub-pixel SP2 on the first surface, allowing the second sub-pixel SP2 to display green independently. Furthermore, the red ink particles reflect red light, and the green ink particles reflect green light with better color saturation, improving display quality.

[0094] The Bragg reflector layer includes a long-pass filter 141, which corresponds to the first sub-pixel SP1. The long-pass filter 141 can transmit red and green light and reflect blue light. Since the second sub-pixel SP2 and the third sub-pixel SP3 achieve color display through green light reflected by green ink particles and red light reflected by red ink particles, respectively, the areas corresponding to the second sub-pixel SP2 and the third sub-pixel SP3 do not need to be equipped with short-pass filters 142.

[0095] Furthermore, the first opposing substrate 11 has a blue light gap layer 113b in the area corresponding to the first sub-pixel SP1 and a red light gap layer 113r in the area corresponding to the third sub-pixel SP3. The blue light gap layer 113b has multiple gaps with a width of 630-780nm. The blue light gap layer 113b can transmit blue light and absorb red and green light, thereby allowing the first sub-pixel SP1 to display blue independently. That is, the blue light gap layer 113b absorbs the red and green light when it is placed on the first opposing substrate 11, and the incident light on the first surface cannot reach the e-ink screen 20, reducing the impact of the e-ink screen 20 on the full-color display of the first surface.

[0096] The light-filtering gap layer (red light gap layer 113r) is based on the principle of light interference. It is formed by setting light-filtering gap layers of different thicknesses and gap widths on the first opposing substrate 11. These gap layers can be etched using nanoimprint lithography or photolithography. This allows for the filtering of different colors of light, achieving the desired light-filtering effect. The structure is simple and the cost is low.

[0097] like Figure 17 and Figure 18 As shown, when the first side displays a full-color image and the second side displays a dual-color image, both the control LCD cell 10 and the e-ink screen 20 are turned on. The LCD cell 10 faces the first side to display the full-color image, and the e-ink screen 20 faces the second side to display the dual-color image (red-green image). In this embodiment, the first sub-pixel SP1 can display blue independently, the second sub-pixel SP2 can display green independently, and the third sub-pixel SP3 can display red independently. Compared to Embodiment 1, the color gamut of the full-color image displayed on the first side is wider. Moreover, the color displayed by the first sub-pixel SP1 is not affected by the e-ink screen 20, reducing the mutual interference between the patterns of the full-color image displayed on the first side and the dual-color image displayed on the second side.

[0098] Specifically, for the e-ink screen 20, when a negative voltage (e.g., -10 to -20V) is applied to the second common electrode 211 in the corresponding second pixel unit P2, and a positive voltage (e.g., +10 to +20V) is applied to the second pixel electrode 221, the electric field direction between the second pixel electrode 221 and the second common electrode 211 is upward. As a result, the first color ink particles 231 move downward and concentrate near the second pixel electrode 221, and the second color ink particles 232 move upward and concentrate near the second common electrode 211. If a positive voltage (e.g., +10 to +20V) is applied to the second common electrode 211 in the corresponding second pixel unit P2, and a negative voltage (e.g., -10 to -20V) is applied to the second pixel electrode 221, the electric field between the second pixel electrode 221 and the second common electrode 211 will be directed downwards. Consequently, the second color ink particles 232 will move downwards and concentrate near the second pixel electrode 221, while the first color ink particles 231 will move upwards and concentrate near the second common electrode 211. In other words, the driving method of the electronic ink screen 20 is basically the same as in Embodiment 1, except that the colors selected by the first color ink particles 231 and the second color ink particles 232 are different, i.e., the colors of the reflected light are different.

[0099] In another embodiment, the first opposing substrate 11 and the first array substrate 12 may also be in a fully transparent state in the areas corresponding to the first sub-pixel SP1 and the second sub-pixel SP2 (i.e., light can completely pass through the first opposing substrate 11 and the first array substrate 12, with virtually no reflection or absorption of light). The first opposing substrate 11 and the first array substrate 12 do not have Bragg reflectors or filter gap layers in the areas corresponding to the first sub-pixel SP1 and the second sub-pixel SP2. One of the first color ink particles 231 and the second color ink particles 232 is a green ink particle, and the other is a blue ink particle. The Bragg reflector layer includes a short-pass filter 142, which corresponds to the third sub-pixel SP3. The short-pass filter 142 can transmit blue light and reflect red and green light. Alternatively, the first opposing substrate 11 and the first array substrate 12 may be completely transparent in the areas corresponding to the first sub-pixel SP1 and the third sub-pixel SP3 (i.e., light can completely pass through the first opposing substrate 11 and the first array substrate 12, with virtually no reflection or absorption of light). The first opposing substrate 11 and the first array substrate 12 do not have Bragg reflectors or filter gap layers in the areas corresponding to the first sub-pixel SP1 and the third sub-pixel SP3. One of the first color ink particles 231 and the second color ink particles 232 is a red ink particle, and the other is a blue ink particle. The Bragg reflector layer includes a short-pass filter 142, which corresponds to the second sub-pixel SP2 and is capable of transmitting blue light and reflecting red and green light.

[0100] Those skilled in the art should understand that the remaining structures and working principles of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0101] [Example 5]

[0102] Figure 19 This is a schematic diagram of the structure of the reflective display device in Embodiment 5 of the present invention, showing a full-color image on the first side and a dual-color image on the second side. Figure 20 This is a schematic diagram of the optical path analysis of the reflective display device in Embodiment 5 of the present invention when displaying a full-color image on the first surface and a dual-color image on the second surface. Figure 19 and Figure 20 As shown, the reflective display device and driving method provided in Embodiment 5 of the present invention are the same as those in Embodiment 1. Figures 1 to 12 The reflective display device and driving method in this embodiment are basically the same, except that in this embodiment:

[0103] The first opposing substrate 11 has a blue light gap layer 113b in the region corresponding to the first sub-pixel SP1, and / or a green light gap layer 113g in the region corresponding to the second sub-pixel SP2, and / or a red light gap layer 113r in the region corresponding to the third sub-pixel SP3. In this embodiment, the first opposing substrate 11 has a blue light gap layer 113b in the region corresponding to the first sub-pixel SP1, a green light gap layer 113g in the region corresponding to the second sub-pixel SP2, and a red light gap layer 113r in the region corresponding to the third sub-pixel SP3. The blue light gap layer 113b has multiple slits with a width of 630-780nm. The blue light gap layer 113b can transmit blue light and absorb red and green light, thereby allowing the first sub-pixel SP1 to display blue light alone. The green light gap layer 113g has multiple slits with a width of 500-570nm. The green light gap layer 113g can transmit green light and absorb red and blue light, thereby allowing the first sub-pixel SP1 to display green light alone. The red light gap layer 113r has multiple gaps with a width of 420-470nm. The red light gap layer 113r can transmit red light and absorb blue and green light, so that the third sub-pixel SP3 can display red independently. That is, the red and green light, red and blue light, and blue and green light are absorbed by the blue light gap layer 113b, green light gap layer 113g, and red light gap layer 113r respectively when the first opposing substrate 11 is in place. The incident light on the first surface cannot reach the e-ink screen 20, and the influence of the e-ink screen 20 on the full-color display of the first surface can be completely avoided. Therefore, the first pixel unit P1 and the second pixel unit P2 do not need to correspond to each other.

[0104] The light-filtering gap layers (blue light gap layer 113b, green light gap layer 113g, and red light gap layer 113r) are based on the principle of light interference. By setting light-filtering gap layers of different thicknesses and gap widths on the first opposing substrate 11, these gap layers can be formed using nanoimprint lithography or photolithography. This allows for the filtering of different colors of light, achieving the desired light-filtering effect. The structure is simple and the cost is low.

[0105] like Figure 19 and Figure 20As shown, when the first side displays a full-color image and the second side displays a dual-color image, both the control LCD cell 10 and the e-ink screen 20 are turned on. The LCD cell 10 faces the first side to display the full-color image, and the e-ink screen 20 faces the second side to display the dual-color image (black and white image). In this embodiment, the first sub-pixel SP1 can display blue independently, the second sub-pixel SP2 can display green independently, and the third sub-pixel SP3 can display red independently. Compared with Embodiment 1, the color gamut of the full-color image displayed on the first side is wider. Moreover, the colors displayed by the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 are not affected by the e-ink screen 20, completely avoiding the mutual influence between the patterns of the full-color image displayed on the first side and the dual-color image displayed on the second side. That is, the LCD cell 10 facing the first side to display the full-color image and the e-ink screen 20 facing the second side to display the dual-color image are independent of each other and do not affect each other; moreover, the colors of the first color ink particles 231 and the second color ink particles 232 do not affect the full-color image displayed on the first side, but only affect the colors of the dual-color image displayed on the second side. Therefore, when the second side displays a full-color image, the control unit 10 turns the e-ink screen 20 on and off; or when the second side displays a dual-color image, the control unit 10 turns the e-ink screen 20 off and on.

[0106] Specifically, for the e-ink screen 20, when a negative voltage (e.g., -10 to -20V) is applied to the second common electrode 211 in the corresponding second pixel unit P2, and a positive voltage (e.g., +10 to +20V) is applied to the second pixel electrode 221, the electric field direction between the second pixel electrode 221 and the second common electrode 211 is upward. As a result, the first color ink particles 231 move downward and concentrate near the second pixel electrode 221, and the second color ink particles 232 move upward and concentrate near the second common electrode 211. If a positive voltage (e.g., +10 to +20V) is applied to the second common electrode 211 in the corresponding second pixel unit P2, and a negative voltage (e.g., -10 to -20V) is applied to the second pixel electrode 221, the electric field between the second pixel electrode 221 and the second common electrode 211 will be directed downwards. Consequently, the second color ink particles 232 will move downwards and concentrate near the second pixel electrode 221, while the first color ink particles 231 will move upwards and concentrate near the second common electrode 211. In other words, the driving method of the electronic ink screen 20 is basically the same as in Embodiment 1, except that the colors selected by the first color ink particles 231 and the second color ink particles 232 are different, i.e., the colors of the reflected light are different.

[0107] Those skilled in the art should understand that the remaining structures and working principles of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0108] In this document, the directional terms such as up, down, left, right, front, and back are defined according to the position of the structures in the accompanying drawings and the relative positions of the structures, and are only used for clarity and convenience in expressing the technical solution. It should be understood that the use of these directional terms should not limit the scope of protection claimed in this application. It should also be understood that the terms "first" and "second," etc., used herein are only used for distinction in name and are not used to limit the number or order.

[0109] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content without departing from the scope of the technical solution of the present invention, which are equivalent embodiments with equivalent changes. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the technical solution of the present invention shall still fall within the protection scope of the technical solution of the present invention.

Claims

1. A reflective double-sided display device, characterized in that, It includes a liquid crystal cell (10) and an electronic ink screen (20) stacked on top of each other, wherein the liquid crystal cell (10) is close to the first side of the reflective double-sided display device, and the electronic ink screen (20) is close to the second side of the reflective double-sided display device; The liquid crystal cell (10) includes a first opposing substrate (11), a first array substrate (12) disposed opposite to the first opposing substrate (11), and a dye liquid crystal layer (13) located between the first opposing substrate (11) and the first array substrate (12). The first opposing substrate (11) is close to a first surface of the liquid crystal cell (10), and the first array substrate (12) is close to a second surface of the liquid crystal cell (10). The liquid crystal cell (10) has a plurality of first pixel units (P1) arranged in an array. The plurality of first pixel units (P1) have a first sub-pixel (SP1), a second sub-pixel (SP2), and a third sub-pixel (SP3). The first array substrate (12) is provided with a first pixel electrode (121) and a Bragg reflective layer. At least one of the first sub-pixel (SP1), the second sub-pixel (SP2), and the third sub-pixel (SP3) corresponds to the Bragg reflective layer. The first opposing substrate (11) is provided with a first common electrode (111) that cooperates with the first pixel electrode (121). The first opposing substrate (11) has a blue light gap layer (113b) in the region corresponding to the first sub-pixel (SP1). The blue light gap layer (113b) has multiple slits with a width of 630~780nm and can transmit blue light and absorb red and green light. And / or a green light gap layer (113g) is provided in the region corresponding to the second sub-pixel (SP2). The green light gap layer (113g) has multiple slits with a width of 500~570nm and can transmit green light and absorb red and blue light. And / or a red light gap layer (113r) is provided in the region corresponding to the third sub-pixel (SP3). The red light gap layer (113r) has multiple slits with a width of 420~470nm and can transmit red light and absorb blue and green light. The electronic ink screen (20) includes a second opposing substrate (21), a second array substrate (22) disposed opposite to the second opposing substrate (21), and ink capsules (23) located between the second opposing substrate (21) and the second array substrate (22). All the ink capsules (23) are provided with first color ink particles (231) and second color ink particles (232) of opposite polarity. The second array substrate (22) is provided with a second pixel electrode (221), and the second opposing substrate (21) is provided with a second common electrode (211) that cooperates with the second pixel electrode (221).

2. The reflective double-sided display device according to claim 1, characterized in that, The Bragg reflector layer includes a long-pass filter (141) and a short-pass filter (142). The long-pass filter (141) corresponds to the first sub-pixel (SP1), and the short-pass filter (142) corresponds to the second sub-pixel (SP2) and the third sub-pixel (SP3). The long-pass filter (141) can transmit red and green light and reflect blue light, and the short-pass filter (142) can transmit blue light and reflect red and green light.

3. The reflective double-sided display device according to claim 2, characterized in that, The first color ink particle (231) is one of black ink particles, white ink particles, red ink particles, green ink particles and blue ink particles, and the second color ink particle (232) is one of black ink particles, white ink particles, red ink particles, green ink particles and blue ink particles. The first color ink particle (231) and the second color ink particle (232) are ink particles of different colors.

4. The reflective double-sided display device according to claim 1, characterized in that, The electronic ink screen (20) has a plurality of second pixel units (P2) arranged in an array, and the first pixel unit (P1) corresponds one-to-one with the second pixel unit (P2).

5. The reflective double-sided display device according to claim 4, characterized in that, The first opposing substrate (11) and the first array substrate (12) are both fully transparent in the area corresponding to the first sub-pixel (SP1). One of the first color ink particles (231) and the second color ink particles (232) is a black ink particle, and the other is a blue ink particle. The Bragg reflection layer includes a short-pass filter (142), which corresponds to the second sub-pixel (SP2) and the third sub-pixel (SP3). The short-pass filter (142) can transmit blue light and reflect red and green light. Alternatively, the first opposing substrate (11) and the first array substrate (12) are both in a fully transparent state in the area corresponding to the second sub-pixel (SP2). One of the first color ink particles (231) and the second color ink particles (232) is a black ink particle, and the other is a green ink particle. The Bragg reflection layer includes a long-pass filter (141) and a short-pass filter (142). The long-pass filter (141) corresponds to the first sub-pixel (SP1), and the short-pass filter (142) corresponds to the third sub-pixel (SP3). The long-pass filter (141) can transmit red and green light and reflect blue light, and the short-pass filter (142) can transmit blue light and reflect red and green light. Alternatively, the first opposing substrate (11) and the first array substrate (12) are both in a fully transparent state in the area corresponding to the third sub-pixel (SP3). One of the first color ink particles (231) and the second color ink particles (232) is a black ink particle, and the other is a red ink particle. The Bragg reflection layer includes a long-pass filter (141) and a short-pass filter (142). The long-pass filter (141) corresponds to the first sub-pixel (SP1), and the short-pass filter (142) corresponds to the second sub-pixel (SP2). The long-pass filter (141) can transmit red and green light and reflect blue light, and the short-pass filter (142) can transmit blue light and reflect red and green light.

6. The reflective double-sided display device according to claim 4, characterized in that, The first opposing substrate (11) and the first array substrate (12) are both fully transparent in the areas corresponding to the first sub-pixel (SP1) and the second sub-pixel (SP2). One of the first color ink particles (231) and the second color ink particles (232) is a green ink particle, and the other is a blue ink particle. The Bragg reflection layer includes a short-pass filter (142), which corresponds to the third sub-pixel (SP3). The short-pass filter (142) can transmit blue light and reflect red and green light. Alternatively, the first opposing substrate (11) and the first array substrate (12) are both fully transparent in the areas corresponding to the first sub-pixel (SP1) and the third sub-pixel (SP3), one of the first color ink particles (231) and the second color ink particles (232) is a red ink particle and the other is a blue ink particle, the Bragg reflection layer includes a short-pass filter (142), the short-pass filter (142) corresponds to the second sub-pixel (SP2), the short-pass filter (142) can transmit blue light and reflect red and green light; Alternatively, the first opposing substrate (11) and the first array substrate (12) are both in a fully transparent state in the areas corresponding to the second sub-pixel (SP2) and the third sub-pixel (SP3). One of the first color ink particles (231) and the second color ink particles (232) is a red ink particle, and the other is a green ink particle. The Bragg reflection layer includes a long-pass filter (141), which corresponds to the first sub-pixel (SP1). The long-pass filter (141) can transmit red and green light and reflect blue light.

7. A driving method for a reflective double-sided display device, characterized in that, The driving method for driving the reflective double-sided display device as described in any one of claims 1-6 includes: When displaying a dual-color image on the second side alone, the control LCD box (10) is turned off and the electronic ink screen (20) is turned on, with the electronic ink screen (20) facing the second side to display the dual-color image; When the first side displays a full-color image and the second side displays a dual-color image, both the liquid crystal cell (10) and the electronic ink screen (20) are turned on. The liquid crystal cell (10) faces the first side to display a full-color image, and the electronic ink screen (20) faces the second side to display a dual-color image.

8. The driving method for the reflective double-sided display device according to claim 7, characterized in that, The Bragg reflector layer includes a long-pass filter (141) and a short-pass filter (142). The long-pass filter (141) corresponds to the first sub-pixel (SP1), and the short-pass filter (142) corresponds to the second sub-pixel (SP2) and the third sub-pixel (SP3). The long-pass filter (141) can transmit red and green light and reflect blue light, and the short-pass filter (142) can transmit blue light and reflect red and green light. One of the first color ink particles (231) and the second color ink particles (232) is a black ink particle. The driving method includes: When displaying a full-color image on the first side alone, the liquid crystal cell (10) is controlled to turn on and off the electronic ink screen (20). All black ink particles in the ink capsules (23) of the electronic ink screen (20) are facing the liquid crystal cell (10), and the liquid crystal cell (10) displays a full-color image facing the first side.

9. The driving method for the reflective double-sided display device according to claim 7, characterized in that, The Bragg reflector layer includes a long-pass filter (141) and a short-pass filter (142). The long-pass filter (141) corresponds to the first sub-pixel (SP1), and the short-pass filter (142) corresponds to the second sub-pixel (SP2) and the third sub-pixel (SP3). The long-pass filter (141) can transmit red and green light and reflect blue light, and the short-pass filter (142) can transmit blue light and reflect red and green light. The first opposing substrate (11) has a blue light gap layer (113b) in the area corresponding to the first sub-pixel (SP1), a green light gap layer (113g) in the area corresponding to the second sub-pixel (SP2), and a red light gap layer (113r) in the area corresponding to the third sub-pixel (SP3). The driving method includes: When displaying a full-color image on the first side alone, the liquid crystal cell (10) is controlled to turn on and off the electronic ink screen (20), and the liquid crystal cell (10) displays a full-color image facing the first side.

Images