Reflective display panel and display device

Abstract

The utility model discloses a reflective display panel and a display device. The reflective display panel comprises a backlight module, a first liquid crystal box, a second liquid crystal box and a third liquid crystal box, wherein the first liquid crystal box, the second liquid crystal box and the third liquid crystal box are sequentially stacked on the backlight module; the first liquid crystal box comprises a first array substrate, a first opposite substrate and a first cholesteric liquid crystal layer; the first cholesteric liquid crystal layer is used for reflecting light of a first color in a reflection state; the second liquid crystal box comprises a second array substrate, a second opposite substrate and a second cholesteric liquid crystal layer; the second cholesteric liquid crystal layer is used for reflecting light of a second color in a reflection state; the third liquid crystal box comprises a third array substrate, a third opposite substrate and a third cholesteric liquid crystal layer; the third cholesteric liquid crystal layer is used for reflecting light of a third color in a reflection state; the backlight module emits backlight from the backlight surface of the first liquid crystal box to the first liquid crystal box. The reflective display panel not only can display when ambient light is dark, but also does not have the problem of depth of field.

Description

Technical Field

[0001] The utility model relates to the field of display technology, and in particular to a reflective display panel and a display device. Background Art

[0002] With the development of display technology, the application of display panels is becoming more and more extensive, and correspondingly, the requirements for display panels are becoming higher and higher.

[0003] In the related art, cholesteric reflective display panels are widely used in electronic readers (such as e-books, e-newspapers, etc.) or other electronic components (such as price tags, etc.) due to their advantages such as low power consumption and no harm to eyes.

[0004] However, the cholesteric reflective display panel in the related art cannot display in a dark environment, and there is a depth of field problem after adding a front light source. Utility Model Content

[0005] The utility model provides a reflective display panel and a display device, so that the reflective display panel can display when the ambient light is dark and there is no depth of field problem.

[0006] According to one aspect of the present invention, a reflective display panel is provided, the reflective display panel comprising:

[0007] A backlight module and a first liquid crystal cell, a second liquid crystal cell and a third liquid crystal cell sequentially stacked on the backlight module;

[0008] The first liquid crystal box includes a first array substrate, a first opposing substrate opposite to the first array substrate, and a first cholesteric liquid crystal layer disposed between the first array substrate and the first opposing substrate; the first cholesteric liquid crystal layer is used to reflect light of a first color in a reflective state;

[0009] The second liquid crystal box includes a second array substrate, a second opposing substrate opposite to the second array substrate, and a second cholesteric liquid crystal layer disposed between the second array substrate and the second opposing substrate; the second cholesteric liquid crystal layer is used to reflect light of a second color in a reflective state;

[0010] The third liquid crystal box comprises a third array substrate, a third opposing substrate opposite to the third array substrate, and a third cholesteric liquid crystal layer disposed between the third array substrate and the third opposing substrate; the third cholesteric liquid crystal layer is used for reflecting light of a third color in a reflective state;

[0011] The backlight module emits backlight toward the first liquid crystal cell from the backlight surface of the first liquid crystal cell.

[0012] Optionally, the reflective display panel further includes a light absorbing layer, and the light absorbing layer is arranged on a side of the backlight module away from the first liquid crystal box.

[0013] Optionally, the reflective display panel further includes a light reflecting layer, and the light reflecting layer is arranged on a side of the backlight module away from the liquid crystal box.

[0014] Optionally, the backlight module includes:

[0015] Light source, light guide plate and dot assembly;

[0016] The light guide plate is arranged on the backlight surface of the first liquid crystal box, the light source is arranged on the light incident end of the light guide plate, and the grid dot assembly includes a plurality of grid dots arranged on a side of the light guide plate away from the first liquid crystal box.

[0017] Optionally, the first liquid crystal box includes a preset substrate; wherein the preset substrate is a substrate of the first array substrate and the first opposing substrate that is away from the display surface of the reflective display panel;

[0018] The backlight module includes a light source, a light guide plate and a mesh dot assembly, the light source is arranged at the light incident end of the light guide plate, and the mesh dot assembly includes a plurality of mesh dots arranged on a side of the light guide plate away from the display surface of the reflective display panel; the preset substrate reuses the light guide plate.

[0019] Optionally, the backlight module further includes a flexible circuit board, one end of the flexible circuit board is electrically connected to the light source, and the other end of the flexible circuit board is bound to the light guide plate.

[0020] Optionally, a plurality of first pixel electrodes are disposed on the first array substrate, and a first common electrode matched with the first pixel electrodes is disposed on the first opposing substrate;

[0021] A plurality of second pixel electrodes are disposed on the second array substrate, and a second common electrode matched with the second pixel electrodes is disposed on the second opposing substrate;

[0022] A plurality of third pixel electrodes are disposed on the third array substrate, and a third common electrode matched with the third pixel electrodes is disposed on the third opposing substrate.

[0023] Optionally, the first color, the second color and the third color are all selected from red, green and blue, and the first color, the second color and the third color are different.

[0024] Optionally, the reflective display panel further includes a light sensor and a processor, the light sensor is used to collect the intensity of ambient light, the processor is electrically connected to the light sensor and the backlight module, and the processor is used to control the state of the backlight module according to the intensity of the ambient light.

[0025] According to another aspect of the present invention, a display device is provided, wherein the display device comprises the reflective display panel as described above.

[0026] The technical solution of the embodiment of the utility model adopts a reflective display panel comprising: a backlight module and a first liquid crystal box, a second liquid crystal box and a third liquid crystal box sequentially stacked on the backlight module; the first liquid crystal box comprises a first array substrate, a first opposing substrate opposite to the first array substrate and a first cholesteric liquid crystal layer arranged between the first array substrate and the first opposing substrate; the first cholesteric liquid crystal layer is used to reflect light of a first color in a reflective state; the second liquid crystal box comprises a second array substrate, a second opposing substrate opposite to the second array substrate and a second cholesteric liquid crystal layer arranged between the second array substrate and the second opposing substrate; the second cholesteric liquid crystal layer is used to reflect light of a second color in a reflective state; the third liquid crystal box comprises a third array substrate, a third opposing substrate opposite to the third array substrate and a third cholesteric liquid crystal layer arranged between the third array substrate and the third opposing substrate; the third cholesteric liquid crystal layer is used to reflect light of a third color in a reflective state; the backlight module emits backlight from the backlight surface of the first liquid crystal box to the first liquid crystal box. By setting a backlight module, when the ambient light is dark, the reflective display panel is provided with backlight, so that the reflective display panel can still display in a dark environment. In addition, the backlight module provides backlight to the liquid crystal box from the backlight surface of the liquid crystal box, which can also improve the depth of field problem and enhance the display effect.

[0027] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present utility model, nor are they intended to limit the scope of the present utility model. Other features of the present utility model will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 A schematic structural diagram of a reflective display panel provided by an embodiment of the utility model;

[0030] Figure 2A schematic diagram of pixel arrangement of a reflective display panel provided by an embodiment of the utility model;

[0031] Figure 3 for Figure 1 A schematic diagram of the circuit structure of the first liquid crystal box;

[0032] Figure 4 This is a schematic diagram showing the principle of the reflective display panel of the embodiment of the utility model displaying red when the ambient light is strong;

[0033] Figure 5 This is a schematic diagram showing the principle of the reflective display panel of the embodiment of the utility model displaying red when the ambient light is weak;

[0034] Figure 6 This is a schematic diagram of the principle of the reflective display panel of the embodiment of the utility model displaying green when the ambient light is strong;

[0035] Figure 7 This is a schematic diagram showing the principle of the reflective display panel of the embodiment of the utility model displaying red when the ambient light is weak;

[0036] Figure 8 This is a schematic diagram showing the principle of the reflective display panel of the embodiment of the utility model displaying blue when the ambient light is strong;

[0037] Fig. 9 This is a schematic diagram showing the principle of the reflective display panel of the embodiment of the utility model displaying blue when the ambient light is weak;

[0038] Fig.10 A schematic structural diagram of another reflective display panel provided in an embodiment of the utility model;

[0039] Fig.11 A schematic structural diagram of a display device provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0040] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0041] It should be noted that the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the utility model described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0042] Figure 1 A schematic diagram of a reflective display panel provided by an embodiment of the present invention, referring to Figure 1 The reflective display panel includes: a backlight module 2 and a first liquid crystal cell 11, a second liquid crystal cell 12 and a third liquid crystal cell 13 sequentially stacked on the backlight module 2; the first liquid crystal cell 11 includes a first array substrate 111, a first opposing substrate 115 opposite to the first array substrate 111 and a first cholesteric liquid crystal layer 113 arranged between the first array substrate 111 and the first opposing substrate 115; the first cholesteric liquid crystal layer 113 is used to reflect light of a first color in a reflective state; the second liquid crystal cell 12 includes a second array substrate 12 ... The backlight module 2 emits backlight from the backlight surface of the first liquid crystal cell 11 to the first liquid crystal cell 11. The backlight module 2 emits backlight from the backlight surface of the first liquid crystal cell 11 to the first liquid crystal cell 11.

[0043] Specifically, the liquid crystal box in the reflective display panel can reflect light of a preset color in the ambient light in the reflective state, so that the user can see the content displayed on the liquid crystal box. More specifically, the liquid crystal box includes a cholesteric liquid crystal layer, wherein the cholesteric liquid crystal layer contains cholesteric liquid crystal, and the cholesteric liquid crystal is, for example, cholesterol liquid crystal. Cholesteric liquid crystal has two stable textures, P state (Planar, planar structure state) and FC state (Focal Conic, focal conic structure state), and both states do not require voltage to maintain. The reflection spectrum of the cholesteric liquid crystal in the P state is in the visible spectrum, and the cholesteric liquid crystal presents bright colors. When the cholesteric liquid crystal is in the FC state, the cholesteric liquid crystal no longer reflects the above-mentioned colored light, and the light is scattered and transmitted. And under the action of a certain electric field, the P state and FC state of the cholesteric liquid crystal can be converted to each other, and these two states can be maintained for a long time without voltage. For example, under zero voltage, when the cholesteric liquid crystal is in the P state in the initial state, it is in the reflective state, and the visible light spectra reflected by the cholesteric liquid crystals in different arrangement directions are different, and the spectra other than the reflective spectrum can pass through the cholesteric liquid crystal. In addition, the reflection spectrum band (Δλ) of the cholesteric liquid crystal is proportional to the helical pitch (Po) and birefringence (Δn=ne-no) of the cholesteric liquid crystal material: Δλ=Po*Δn. When a voltage is applied across the cholesteric liquid crystal and then the voltage is slowly reduced to zero, the cholesteric liquid crystal molecules rotate and stagnate in the FC state, which is a scattering state. When a voltage is applied across the cholesteric liquid crystal, the cholesteric liquid crystal is in the H (Homeotropic, vertical alignment) state, which is a transparent state. This state is unstable and requires voltage to maintain.

[0044] By controlling the state of the liquid crystal box, such as controlling the state of the cholesteric liquid crystal in different sub-pixels in the liquid crystal box, the reflected light or transmitted light of different sub-pixels in the liquid crystal box can be controlled, so that the user can view the corresponding image. The first color, the second color and the third color are different from each other. By controlling the states of different sub-pixels in the first liquid crystal box 11, the second liquid crystal box 12 and the third liquid crystal box 13, the reflective display panel realizes color display.

[0045] In this embodiment, the reflective display panel includes a display surface and a backlight surface, and the user views the reflective display panel from the display surface side of the reflective display panel. In other words, the display surface of the reflective display panel is the side of the reflective display panel that is closer to the external environment. Each liquid crystal box includes a light-emitting surface and a backlight surface, wherein the light-emitting surface and the backlight surface of the liquid crystal box are the side closer to the external environment relative to the user viewing the reflective display panel as the light-emitting surface, and the other side as the backlight surface. Figure 1 In the structure shown, the light-emitting surface of the liquid crystal cell is the side facing upward, and the backlight surface is the side facing downward.

[0046] In this embodiment, by setting the backlight module 2, the reflective display panel can display in the case of dark or bright ambient light. When the ambient light is bright, the light with sufficient intensity in the ambient light can be reflected into the user's eyes, and the backlight module 2 does not need to work. When the ambient light is dark, the light reflected into the user's eyes in the ambient light is weak, and the user may not be able to see the image. Therefore, at this time, the backlight module 2 can be controlled to work, and the backlight module 2 provides backlight from the backlight surface of the liquid crystal box, so that the light entering the user's eyes is strong, and the user can see the image.

[0047] In this embodiment, the backlight module 2 is arranged on the backlight surface of the liquid crystal box, which can improve the depth of field problem and further enhance the display effect compared to the case where the backlight module 2 is arranged on the light emitting surface of the liquid crystal box.

[0048] The technical solution of this embodiment adopts a reflective display panel including: a backlight module and a first liquid crystal box, a second liquid crystal box and a third liquid crystal box sequentially stacked on the backlight module; the first liquid crystal box includes a first array substrate, a first opposing substrate opposite to the first array substrate and a first cholesteric liquid crystal layer arranged between the first array substrate and the first opposing substrate; the first cholesteric liquid crystal layer is used to reflect light of a first color in a reflective state; the second liquid crystal box includes a second array substrate, a second opposing substrate opposite to the second array substrate and a second cholesteric liquid crystal layer arranged between the second array substrate and the second opposing substrate; the second cholesteric liquid crystal layer is used to reflect light of a second color in a reflective state; the third liquid crystal box includes a third array substrate, a third opposing substrate opposite to the third array substrate and a third cholesteric liquid crystal layer arranged between the third array substrate and the third opposing substrate; the third cholesteric liquid crystal layer is used to reflect light of a third color in a reflective state; the backlight module emits backlight from the backlight surface of the first liquid crystal box to the first liquid crystal box. By setting a backlight module, when the ambient light is dark, the reflective display panel is provided with backlight, so that the reflective display panel can still display in a dark environment. In addition, the backlight module provides backlight to the liquid crystal box from the backlight surface of the liquid crystal box, which can also improve the depth of field problem and enhance the display effect.

[0049] The following first describes the display principle of the reflective display panel. Each liquid crystal box includes a plurality of sub-pixels, and the sub-pixels include cholesteric liquid crystal molecules. The colors of the light reflected by the sub-pixels in different liquid crystal boxes are different in the reflective state. The reflective display panel may include a plurality of pixels, and each pixel includes at least one sub-pixel reflecting a first color (represented by a first sub-pixel), at least one sub-pixel reflecting a second color (represented by a second sub-pixel), and at least one sub-pixel reflecting a third color (represented by a third sub-pixel). The first sub-pixel, the second sub-pixel, and the third sub-pixel in the pixel are respectively located in the first liquid crystal box 11, the second liquid crystal box 12, and the third liquid crystal box 13. In some embodiments, along the thickness direction of the reflective display panel, the projections of the first sub-pixel, the second sub-pixel, and the third sub-pixel overlap, thereby improving the pixel resolution of the reflective display panel. It is also understood that each sub-pixel can adjust the intensity of the light reflected in the reflective state by adjusting the voltage applied to both sides of the cholesteric liquid crystal molecules.

[0050] When the ambient light is strong, the backlight module 2 does not work. If it is necessary to control the pixel to display a preset color, the sub-pixel that reflects the preset color in the reflective state is adjusted to the reflective state, and the other sub-pixels are adjusted to the scattering state or transparent state. Thus, when the ambient light irradiates the pixel, the preset color light is reflected to the user's eyes, and the other color light is transmitted to the inside of the liquid crystal box, and the pixel displays the preset color.

[0051] When the ambient light is weak, the backlight module 2 works. Since the light provided by the backlight module 2 is backlight, in contrast to when the ambient light is strong, if it is necessary to control the pixel to display a preset color, the sub-pixel in the pixel that reflects the preset color in the reflection state is adjusted to the scattering state or transparent state, and the light of the preset color in the backlight can pass through the liquid crystal box into the user's eyes. The other sub-pixels in the pixel are adjusted to the reflection state, and the light of other colors in the backlight will be reflected back into the liquid crystal box, so that the user only sees the light of the preset color, and the pixel displays the preset color.

[0052] It should be noted that the preset color can be the first color, the second color or the third color. Of course, since the intensity of the reflected light of the cholesteric liquid crystal in each liquid crystal cell is adjustable, the preset color can also be other colors in the visible light spectrum formed by the cooperation of multiple sub-pixels in the pixel.

[0053] Optionally, the first color, the second color and the third color are all selected from red, green and blue, and the first color, the second color and the third color are different. For example, the first color, the second color and the third color are red, green and blue respectively; or the first color, the second color and the third color are red, blue and green respectively; or the first color, the second color and the third color are green, red and blue respectively; or the first color, the second color and the third color are green, blue and red respectively; or the first color, the second color and the third color are blue, red and green respectively; or the first color, the second color and the third color are blue, green and red respectively.

[0054] Optionally, Figure 2 A schematic diagram of pixel arrangement of a reflective display panel provided in an embodiment of the utility model, Figure 3 for Figure 1 The circuit structure diagram of the first liquid crystal box in FIG. Figures 1 to 3 A plurality of first pixel electrodes 112 are disposed on the first array substrate 111, and a first common electrode 114 cooperating with the first pixel electrodes 112 is disposed on the first opposing substrate 115; a plurality of second pixel electrodes 122 are disposed on the second array substrate 121, and a second common electrode 124 cooperating with the second pixel electrodes 122 is disposed on the second opposing substrate 125; a plurality of third pixel electrodes 132 are disposed on the third array substrate 131, and a third common electrode 134 cooperating with the third pixel electrodes 132 is disposed on the third opposing substrate 135.

[0055] Specifically, the first array substrate 111, the first opposing substrate 115, the second array substrate 121, the second opposing substrate 125, the third array substrate 131 and the third opposing substrate 135 may include materials such as glass, acrylic or polycarbonate. The first pixel electrode 112, the first common electrode 114, the second pixel electrode 122, the second common electrode 124, the third pixel electrode 131 and the third common electrode 134 may include materials such as indium tin oxide or indium zinc oxide. Each pixel electrode corresponds to a sub-pixel SPx, that is, each first pixel electrode 112 corresponds to a first sub-pixel R, each second pixel electrode 122 corresponds to a second sub-pixel G, and each third pixel electrode 132 corresponds to a third sub-pixel B. In the reflective display panel, in the same pixel Px, the first sub-pixel R, the second sub-pixel G and the third sub-pixel B are aligned with each other, that is, the projections along the thickness direction of the reflective display panel coincide. Taking the first liquid crystal box as an example, as Figure 3As shown, each array substrate includes a plurality of data lines DL and a plurality of scan lines GL that are staggered horizontally and vertically, and the data lines DL and the scan lines GL are insulated and crossed to define the area of ​​the corresponding sub-pixel. Each sub-pixel includes a control switch T1, a pixel electrode, a cholesteric liquid crystal and a common electrode, wherein the first end of the control switch T1 is electrically connected to the pixel electrode, the second end is electrically connected to the data line DL, and the control end is electrically connected to the scan line DL. When it is necessary to control the state of the sub-pixel SPx, when there is a signal on the scan line GL corresponding to the sub-pixel, the signal can be transmitted to the pixel electrode through the corresponding data line DL, thereby controlling the voltage at both ends of the cholesteric liquid crystal layer in the sub-pixel, so that the state of the cholesteric liquid crystal changes. For example, if it is necessary to make the sub-pixel in a reflective state, a 0V voltage is applied to the common electrode corresponding to the sub-pixel, and no voltage is applied to the pixel electrode. When it is necessary to make the sub-pixel in a scattered state, a 0V voltage is applied to the common electrode corresponding to the sub-pixel, and a grayscale voltage is applied to the pixel electrode, and the grayscale voltage is gradually adjusted to 0V, so that the sub-pixel is in a scattered state.

[0056] Exemplarily, the first cholesteric liquid crystal layer 113 reflects blue light in the reflective state, the second cholesteric liquid crystal layer 123 reflects green light in the reflective state, and the third cholesteric liquid crystal layer 133 reflects red light in the reflective state. Figure 4 As shown, Figure 4 The schematic diagram of the principle of the reflective display panel of the embodiment of the utility model showing red when the ambient light is strong. When the ambient light is strong, the backlight module 2 does not work. At this time, a grayscale voltage is applied to the first pixel electrode 112 and the second pixel electrode 122, and the grayscale voltage is gradually reduced to zero, and a 0V voltage is applied to the first common electrode 114 and the second common electrode 124, so that the first cholesteric liquid crystal layer 113 and the second cholesteric liquid crystal layer 123 are in a scattering state. No voltage is applied to the third pixel electrode 132, and a 0V voltage is applied to the third common electrode, so that the third cholesteric liquid crystal layer 133 is in a reflective state. When the visible light Lw (at this time, ambient light) is incident on the third cholesteric liquid crystal layer 133, the red light Lr is reflected, and other color lights are transmitted, so that the reflective display panel appears red.

[0057] like Figure 5 As shown, Figure 5The schematic diagram of the principle of the reflective display panel of the embodiment of the utility model showing red when the ambient light is weak. When the ambient light is weak, the backlight module 2 works. At this time, no voltage is applied to the first pixel electrode 112 and the second pixel electrode 122, and a 0V voltage is applied to the first common electrode 114 and the second common electrode 124, so that the first cholesteric liquid crystal layer 113 and the second cholesteric liquid crystal layer 123 are in a reflective state. A grayscale voltage is applied to the third pixel electrode 132, and the grayscale voltage is gradually reduced to 0V, and a 0V voltage is applied to the third common electrode, so that the third cholesteric liquid crystal layer 133 is in a scattering state. When the visible light Lw (backlight at this time) is incident on the first cholesteric liquid crystal layer 113, the blue light Lb is reflected, and when the remaining light is incident on the second cholesteric liquid crystal layer 123, the green light Lg is reflected, and other color lights (red light Lr) are transmitted, so that the reflective display panel appears red.

[0058] like Figure 6 As shown, Figure 6 The schematic diagram of the principle of the reflective display panel of the embodiment of the utility model showing green when the ambient light is strong. When the ambient light is strong, the backlight module 2 does not work. At this time, a grayscale voltage is applied to the first pixel electrode 112 and the third pixel electrode 132, and the grayscale voltage is gradually reduced to zero, and a 0V voltage is applied to the first common electrode 114 and the third common electrode 134, so that the first cholesteric liquid crystal layer 113 and the third cholesteric liquid crystal layer 133 are in a scattering state. No voltage is applied to the second pixel electrode 122, and a 0V voltage is applied to the second common electrode, so that the second cholesteric liquid crystal layer 123 is in a reflective state. When the visible light Lw (at this time, ambient light) is incident on the second cholesteric liquid crystal layer 123, the green light Lg is reflected, and other color lights are transmitted, so that the reflective display panel appears green.

[0059] like Figure 7 As shown, Figure 7 The schematic diagram of the principle of the reflective display panel of the embodiment of the utility model showing red when the ambient light is weak. When the ambient light is weak, the backlight module 2 works. At this time, no voltage is applied to the first pixel electrode 112 and the third pixel electrode 132, and a 0V voltage is applied to the first common electrode 114 and the third common electrode 134, so that the first cholesteric liquid crystal layer 113 and the third cholesteric liquid crystal layer 133 are in a reflective state. A grayscale voltage is applied to the second pixel electrode 122, and the grayscale voltage is gradually reduced to 0V, and a 0V voltage is applied to the second common electrode, so that the second cholesteric liquid crystal layer 123 is in a scattering state. When the visible light Lw (backlight at this time) is incident on the first cholesteric liquid crystal layer 113, the blue light Lb is reflected, and when the remaining light is incident on the third cholesteric liquid crystal layer 133, the red light Lr is reflected, and other color lights (green light Lg) are transmitted, so that the reflective display panel appears green.

[0060] like Figure 8As shown, Figure 8 The schematic diagram of the principle of the reflective display panel of the embodiment of the utility model showing blue when the ambient light is strong. When the ambient light is strong, the backlight module 2 does not work. At this time, a grayscale voltage is applied to the second pixel electrode 122 and the third pixel electrode 132, and the grayscale voltage is gradually reduced to zero, and a 0V voltage is applied to the second common electrode 124 and the third common electrode 134, so that the second cholesteric liquid crystal layer 123 and the third cholesteric liquid crystal layer 133 are in a scattering state. No voltage is applied to the first pixel electrode 112, and a 0V voltage is applied to the first common electrode, so that the first cholesteric liquid crystal layer 113 is in a reflective state. When the visible light Lw (at this time, ambient light) is incident on the first cholesteric liquid crystal layer 113, the blue light Lb is reflected, and other color lights are transmitted, so that the reflective display panel appears blue.

[0061] like Fig. 9 As shown, Fig. 9 The schematic diagram of the principle of the reflective display panel of the embodiment of the utility model showing blue when the ambient light is weak. When the ambient light is weak, the backlight module 2 works. At this time, no voltage is applied to the second pixel electrode 122 and the third pixel electrode 132, and a 0V voltage is applied to the second common electrode 124 and the third common electrode 134, so that the second cholesteric liquid crystal layer 123 and the third cholesteric liquid crystal layer 133 are in a reflective state. A grayscale voltage is applied to the first pixel electrode 112, and the grayscale voltage is gradually reduced to 0V, and a 0V voltage is applied to the first common electrode, so that the first cholesteric liquid crystal layer 113 is in a scattering state. Visible light Lw (backlight at this time) passes through the first cholesteric liquid crystal layer 113, and when it is incident on the second cholesteric liquid crystal layer 123, the green light Lg is reflected, and when the remaining light is incident on the third cholesteric liquid crystal layer 133, the red light Lr is reflected, and other color lights (blue light Lb) are transmitted, so that the reflective display panel appears blue.

[0062] Optionally, refer to Figures 1 to 9 The reflective display panel further includes a light absorbing layer 3 , which is disposed on a side of the backlight module 2 away from the first liquid crystal cell 11 .

[0063] Specifically, the backlight emitted by the backlight module 2 is reflected by the liquid crystal box, and the ambient light is not reflected by the liquid crystal box. The light will be transmitted to the backlight surface of the first liquid crystal box. By setting the light absorption layer 3, this part of the light is absorbed to prevent this part of the light from affecting the display of the reflective display panel. By setting the light absorption layer 3, it is possible to prevent this part of the light from being reflected back into the user's eyes, thereby making the contrast of the reflective display panel higher and the display effect better. In addition, compared with setting a reflective layer to reflect this part of the light, the cost of the light absorption layer 3 is lower. The light absorption layer 3 can be made of black material, such as titanium dioxide.

[0064] Optionally, in some other embodiments, the reflective display panel further includes a light reflecting layer (not shown), which is disposed on a side of the backlight module 2 away from the first liquid crystal box. By providing the light reflecting layer, it is possible to prevent light from being emitted from the back of the reflective display panel. In addition, even if part of the light is reflected by the light reflecting layer to the light emitting surface of the reflective display panel, the intensity of the light is relatively small due to the attenuation of the light passing through the multi-layer array substrate, the cholesteric liquid crystal and the opposing substrate, and the user still mainly observes the light reflected by the corresponding liquid crystal box.

[0065] It should be noted that in the above embodiments, the array substrate in each liquid crystal cell is close to the backlight module 2. In other embodiments, the opposing substrate in the liquid crystal cell may be close to the backlight module 2, and the array substrate may be far away from the backlight module 2.

[0066] Optionally, in some embodiments, the first liquid crystal cell 11 and the second liquid crystal cell 12 are bonded together by optical glue. Optionally, the second liquid crystal cell 12 and the third liquid crystal cell 13 are bonded together by optical glue.

[0067] Optionally, the first liquid crystal cell 11 and the second liquid crystal cell 12 may share a substrate, that is, the first liquid crystal cell 11 and the second liquid crystal cell 12 may share adjacent substrates (array substrates or opposing substrates).

[0068] Optionally, the second liquid crystal cell 12 and the third liquid crystal cell 13 may share a substrate, that is, the second liquid crystal cell 12 and the third liquid crystal cell 13 may share adjacent substrates (array substrates or opposing substrates).

[0069] Optionally, refer to Figure 1 The backlight module 2 includes: a light source 21, a light guide plate 24 and a dot assembly 23; the light guide plate 24 is arranged on the backlight surface of the first liquid crystal box 11, the light source 21 is arranged at the light incident end of the light guide plate 24, and the dot assembly 23 includes a plurality of dots arranged on a side of the light guide plate 24 away from the first liquid crystal box 11.

[0070] Specifically, the light source 21 is, for example, an LED (Light Emitting Diode), and the light emitted by the light source 21 is incident from the side (i.e., the light incident end) of the light guide plate 24. The dot assembly 23 provided on the light guide plate 24 totally reflects the light incident into the light guide plate 24, and emits the light from the side of the light guide plate 24 close to the first liquid crystal cell 11. Thus, the light guide plate 24 and the dot assembly 23 cooperate to convert the light emitted by the light source 21 into a surface light source incident from the backlight surface of the first liquid crystal cell 11, i.e., backlight.

[0071] Optionally, refer to Figure 1The backlight module 2 further includes a flexible circuit board 22, one end of which is electrically connected to the light source 21, and the other end of which is bound to the light guide plate 23. The flexible circuit board 22 is used to provide a driving signal for the light source 21. In this embodiment, since there are no or fewer signal lines on the side of the light guide plate 23 close to the first liquid crystal cell 11 or the side away from the first liquid crystal cell 11, the flexible circuit board 22 can be bound to the side of the light guide plate 22 close to the first liquid crystal cell 11 or the side of the light guide plate 22 away from the first liquid crystal cell 11.

[0072] Optionally, Fig.10 A schematic diagram of a reflective display panel according to an embodiment of the present invention is provided. Fig.10 The first liquid crystal box 11 includes a preset substrate; wherein the preset substrate is a substrate of the first array substrate 11 and the first opposing substrate 15 that is away from the display surface of the reflective display panel. The backlight module 2 includes a light source 22, a light guide plate and a mesh dot assembly 23, wherein the light source 22 is arranged at the light incident end of the light guide plate, and the mesh dot assembly 23 includes a plurality of mesh dots 231 arranged on a side of the light guide plate that is away from the display surface of the reflective display panel; the preset substrate is reused as the light guide plate.

[0073] Specifically, Figure 1 The difference between the embodiments shown is that the preset substrate in this embodiment is reused as a light guide plate, so that the backlight emitted by the light guide plate can pass through one less film layer (ie Figure 1 The light guide plate in the reflective display panel can be used to reduce the loss of light by one layer of film, thereby saving the power consumption of the reflective display panel.

[0074] Optionally, continue to refer to Fig.10 In this embodiment, the preset substrate is a first array substrate 111. A signal line for driving sub-pixels is provided on a side of the first array substrate 111 close to the display surface of the reflective display panel, and there is less remaining space. Therefore, a flexible circuit board 22 can be set to be bound to a side of the light guide plate (i.e., the preset substrate) away from the backlight surface of the reflective display panel.

[0075] It should be noted that, when the first array substrate 111 is multiplexed as a light guide plate, the thickness of the first array substrate 111 may be the same as or different from the thickness when the first array substrate 111 is not multiplexed as a light guide plate.

[0076] In addition, the display principle of the reflective display panel in this embodiment when the ambient light is strong or dark can refer to the display principle of the reflective display panel described above, which will not be repeated here.

[0077] Optionally, the reflective display panel further includes a light sensor and a processor, the light sensor is used to collect the intensity of ambient light, the processor is electrically connected to the light sensor and the backlight module, and the processor is used to control the state of the backlight module according to the intensity of the ambient light.

[0078] Specifically, the backlight intensity of the reflective display panel in this embodiment can be automatically adjusted. When the ambient light intensity is weak, the processor controls the state of the backlight module according to the signal collected by the light sensor, for example, the light source in the backlight module can be turned on, and the intensity of the light emitted by the light source in the backlight module can be controlled to be greater when the ambient light is weaker. When the ambient light is strong, the processor controls the state of the backlight module according to the signal collected by the light sensor, for example, the intensity of the light emitted by the light source in the backlight module can be reduced, or the light source in the backlight module can be turned off. Optionally, the processor can be a driver chip, etc.

[0079] The present utility model also provides a display device, such as Fig.11 As shown, Fig.11 A schematic diagram of the structure of a display device provided in an embodiment of the utility model. The display device includes the reflective display panel provided in any embodiment of the utility model. The display device can be a mobile phone, a tablet computer, an MP3, an MP4, a videophone, a personal digital assistant, a smart watch, a smart helmet or other wearable devices. Because it includes the reflective display panel provided in any embodiment of the utility model, it also has the same beneficial effects, which will not be described in detail here.

[0080] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0081] The above specific implementations do not constitute a limitation on the protection scope of the present utility model. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A reflective display panel, characterized in that: The reflective display panel comprises: A backlight module and a first liquid crystal cell, a second liquid crystal cell and a third liquid crystal cell sequentially stacked on the backlight module; The first liquid crystal box includes a first array substrate, a first opposing substrate opposite to the first array substrate, and a first cholesteric liquid crystal layer disposed between the first array substrate and the first opposing substrate; the first cholesteric liquid crystal layer is used to reflect light of a first color in a reflective state; The second liquid crystal box includes a second array substrate, a second opposing substrate opposite to the second array substrate, and a second cholesteric liquid crystal layer disposed between the second array substrate and the second opposing substrate; the second cholesteric liquid crystal layer is used to reflect light of a second color in a reflective state; The third liquid crystal box comprises a third array substrate, a third opposing substrate opposite to the third array substrate, and a third cholesteric liquid crystal layer disposed between the third array substrate and the third opposing substrate; the third cholesteric liquid crystal layer is used for reflecting light of a third color in a reflective state; The backlight module emits backlight toward the first liquid crystal cell from the backlight surface of the first liquid crystal cell.

2. The reflective display panel according to claim 1, characterized in that: The reflective display panel further includes a light absorbing layer, and the light absorbing layer is arranged on a side of the backlight module away from the first liquid crystal box.

3. The reflective display panel according to claim 1, characterized in that: The reflective display panel further comprises a light reflecting layer, and the light reflecting layer is arranged on a side of the backlight module away from the liquid crystal box.

4. The reflective display panel according to claim 1, wherein: The backlight module comprises: Light source, light guide plate and dot assembly; The light guide plate is arranged on the backlight surface of the first liquid crystal box, the light source is arranged on the light incident end of the light guide plate, and the grid dot assembly includes a plurality of grid dots arranged on a side of the light guide plate away from the first liquid crystal box.

5. The reflective display panel according to claim 1, characterized in that: The first liquid crystal box includes a preset substrate; wherein the preset substrate is a substrate of the first array substrate and the first opposing substrate that is away from the display surface of the reflective display panel; The backlight module includes a light source, a light guide plate and a mesh dot assembly, the light source is arranged at the light incident end of the light guide plate, and the mesh dot assembly includes a plurality of mesh dots arranged on a side of the light guide plate away from the display surface of the reflective display panel; the preset substrate reuses the light guide plate.

6. The reflective display panel according to claim 4 or 5, characterized in that: The backlight module further comprises a flexible circuit board, one end of which is electrically connected to the light source, and the other end of which is bound to the light guide plate.

7. The reflective display panel according to claim 1, characterized in that: A plurality of first pixel electrodes are disposed on the first array substrate, and a first common electrode matched with the first pixel electrodes is disposed on the first opposing substrate; A plurality of second pixel electrodes are disposed on the second array substrate, and a second common electrode matched with the second pixel electrodes is disposed on the second opposing substrate; A plurality of third pixel electrodes are disposed on the third array substrate, and a third common electrode matched with the third pixel electrodes is disposed on the third opposing substrate.

8. The reflective display panel according to claim 1, wherein: The first color, the second color and the third color are all selected from red, green and blue, and the first color, the second color and the third color are different from each other.

9. The reflective display panel according to claim 1, characterized in that: The reflective display panel further includes a light sensor and a processor, wherein the light sensor is used to collect the intensity of ambient light, the processor is electrically connected to the light sensor and the backlight module, and the processor is used to control the state of the backlight module according to the intensity of the ambient light.

10. A display device, characterized in that: The display device comprises the reflective display panel according to any one of claims 1 to 9.

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