Reflective display panel and reflective display device

Abstract

The application discloses a reflective display panel and a reflective display device. The reflective display panel comprises a first substrate, a second substrate and a cholesteric liquid crystal layer. The cholesteric liquid crystal layer reflects blue light in a reflective state. The reflective display panel has a plurality of pixel units. The first substrate is provided with a black matrix, a color resistance layer and a light excitation layer. The projection of the color resistance layer and the light excitation layer on the first substrate overlaps with each other. The color resistance layer is arranged on the side of the light excitation layer away from the cholesteric liquid crystal layer. The first substrate is provided with a light filtering area and a light transmitting area. The color resistance layer and the light excitation layer are stacked with each other in the light filtering area. The first substrate is in a transparent state in the light transmitting area. The cholesteric liquid crystal layer reflecting blue light is matched with the light excitation layer and the color resistance layer. The light filtering area and the light transmitting area are arranged on the first substrate. The reflected blue light can excite the light excitation layer to emit light of corresponding colors. Therefore, the single-layer cholesteric liquid crystal layer can realize the display of multiple colors.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a reflective display panel and a reflective display device. BACKGROUND

[0002] The display panel has the advantages of thinness, durability, low power consumption and environmental protection, but needs to be used with a backlight source, resulting in a thick module and high cost. Electronic paper display (reflective display) has become a display that meets the needs of the public. Electronic paper display can display images using external light source, unlike liquid crystal display which needs a backlight source. Therefore, in the outdoor environment with strong sunlight, the information on the electronic paper can still be clearly seen without the problem of viewing angle. In addition, electronic paper display has the advantages of power saving, high reflectivity and contrast ratio, and is now widely used in electronic readers (such as electronic books and electronic newspapers) or other electronic components (such as price tags).

[0003] The existing electronic paper display usually adopts E-Ink microcapsule technology (microcapsule electronic ink technology), SiPix microcup technology (microcup type electrophoretic display technology), Bridgestone electronic liquid powder technology, cholesteric liquid crystal display (CLCD) technology, micro-electro-mechanical system (MEMS) technology or electrowetting technology. However, the existing electronic paper display technology is not very mature compared with liquid crystal display technology, the production efficiency is low, the manufacturing cost is relatively high, and the existing electronic paper display cannot realize color display.

[0004] The electronic tag display device using cholesteric liquid crystal molecules in the prior art can only reflect one color and transmit light of other colors due to the requirement of the pitch of cholesteric liquid crystal molecules. It is difficult to set cholesteric liquid crystal molecules reflecting different colors in the same cholesteric liquid crystal cell, and the existing process level is almost impossible to achieve or the cost is relatively high. Figure 1 is a structural schematic diagram of an electronic tag display device using a three-layer cholesteric liquid crystal cell in the prior art, as shown in Figure 1 If white display or color display is needed, the electronic tag display device needs to use a three-layer cholesteric liquid crystal cell to reflect red / green / blue light, so as to realize white display and color display. However, the three-layer cholesteric liquid crystal cell not only has a large cell thickness, but also has a high cost. SUMMARY

[0005] In order to overcome the shortcomings and deficiencies in the prior art, the purpose of the present application is to provide a reflective display panel and a reflective display device to solve the problem of poor color reflection of the reflective display device using single-layer cholesteric liquid crystal molecules in the prior art.

[0006] The object of the present application is achieved by the following technical solutions:

[0007] The present application provides a reflective display panel, comprising a first substrate, a second substrate arranged opposite to the first substrate, and a cholesteric liquid crystal layer between the first substrate and the second substrate, all cholesteric liquid crystal molecules in the cholesteric liquid crystal layer reflect blue light in a reflective state, one of the first substrate and the second substrate is an array substrate and is provided with a pixel electrode, and the other is provided with a common electrode matched with the pixel electrode.

[0008] The reflective display panel has a plurality of pixel units arranged in an array, the first substrate is provided with a black matrix, a color resistance layer, and a light excitation layer, the black matrix separates the plurality of pixel units from each other, the light excitation layer can absorb blue light and excite light corresponding to the color of the light excitation layer, the color resistance layer and the light excitation layer are overlapped with each other in the projection of the first substrate, and the color resistance layer is arranged on the side of the light excitation layer away from the cholesteric liquid crystal layer.

[0009] The first substrate is provided with a light filtering area and a light transmitting area, the color resistance layer and the light excitation layer are stacked with each other in the light filtering area, and the first substrate is in a transparent state in the light transmitting area.

[0010] Further, the plurality of pixel units have a first pixel unit and a second pixel unit, the color resistance layer comprises a red color resistance layer and a green color resistance layer, the light excitation layer comprises a red light excitation layer and a green light excitation layer, the red color resistance layer and the red light excitation layer are stacked with each other in the first pixel unit, and the green color resistance layer and the green light excitation layer are stacked with each other in the second pixel unit.

[0011] Further, the light filtering area and the light transmitting area are arranged in each pixel unit.

[0012] Further, the light filtering area in each pixel unit is arranged on both sides of the light transmitting area.

[0013] Or, the light filtering area in each pixel unit is arranged on one side of the pixel unit, and the light transmitting area is arranged on the other side of the pixel unit.

[0014] Further, each pixel unit is provided with a light shielding barrier, and the light shielding barrier in each pixel unit is arranged between the light filtering area and the light transmitting area and used to separate the light filtering area and the light transmitting area from each other.

[0015] Further, the plurality of pixel units has a third pixel unit, the light filtering region corresponds to the first pixel unit and the second pixel unit, and the light transmitting region corresponds to the third pixel unit.

[0016] Further, the third pixel unit is arranged between the first pixel unit and the second pixel unit.

[0017] Further, the second substrate is provided with a light absorbing layer, and the light absorbing layer is used for absorbing light passing through the cholesteric liquid crystal layer.

[0018] The application further provides a reflective display device comprising the reflective display panel.

[0019] Further, the reflective display device further comprises a side-in light source module, and the side-in light source module is arranged on a side of the first substrate away from the cholesteric liquid crystal layer and is used for providing a light source to a side of the cholesteric liquid crystal layer.

[0020] The application has the advantages that: the cholesteric liquid crystal layer reflecting blue light is combined with the light excitation layer, the light filtering region and the light transmitting region are arranged on the first substrate, the reflected blue light can make the light excitation layer excite light of corresponding colors, so that the single-layer cholesteric liquid crystal layer can realize display of multiple colors; the color resistance layer combined with the light excitation layer is arranged on a side of the light excitation layer away from the cholesteric liquid crystal layer, the blue light not used by the light excitation layer is absorbed by the color resistance layer, so that the color of the light emitted by the light filtering region is purer, in addition, when ambient light irradiates the light filtering region, the light of different colors from the color resistance layer in the ambient light is absorbed by the color resistance layer, so that the light excitation layer directly uses the ambient light to excite light, and the brightness of the pixel unit in the screen-off or black state is affected. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a structure diagram of a reflective display device adopting a three-layer cholesteric liquid crystal cell in the prior art;

[0022] Figure 2 is a structure diagram of the reflective display device in the initial state in the embodiment one of the application;

[0023] Figure 3 is a plane structure diagram of the first substrate in the embodiment one of the application;

[0024] Figure 4 is a plane structure diagram of the second substrate in the embodiment one of the application;

[0025] Figure 5 is a principle diagram of three state transformations of cholesteric liquid crystal molecules in the embodiment one of the application;

[0026] Figure 6 is the driving signal schematic diagram of three state transformations of the cholesteric liquid crystal molecules in embodiment one of the present application;

[0027] Figure 7 is the structural schematic diagram of the reflective display device displaying black and white picture by using ambient light in embodiment one of the present application;

[0028] Figure 8 is the structural schematic diagram of the reflective display device displaying purple black picture by using ambient light in embodiment one of the present application;

[0029] Figure 9 is the structural schematic diagram of the reflective display device displaying cyan black picture by using ambient light in embodiment one of the present application;

[0030] Figure 10 is the structural schematic diagram of the reflective display device displaying purple gray picture by using ambient light in embodiment one of the present application;

[0031] Figure 11 is the structural schematic diagram of the reflective display device displaying cyan gray picture by using ambient light in embodiment one of the present application;

[0032] Figure 12 is the structural schematic diagram of the reflective display device displaying black and white picture by using side-in light source in embodiment one of the present application;

[0033] Figure 13 is the structural schematic diagram of the reflective display device displaying purple black picture by using side-in light source in embodiment one of the present application;

[0034] Figure 14 is the structural schematic diagram of the reflective display device displaying cyan black picture by using side-in light source in embodiment one of the present application;

[0035] Figure 15 is the structural schematic diagram of the reflective display device displaying purple gray picture by using side-in light source in embodiment one of the present application;

[0036] Figure 16 is the structural schematic diagram of the reflective display device displaying cyan gray picture by using side-in light source in embodiment one of the present application;

[0037] Figure 17 is the incident light principle schematic diagram of the filter area of the reflective display device in embodiment one of the present application;

[0038] Figure 18 is the reflected light principle schematic diagram of the filter area of the reflective display device in embodiment one of the present application;

[0039] Figure 19 is the structural schematic diagram of the reflective display device in the initial state in embodiment two of the present application;

[0040] Figure 20 is a schematic diagram of a planar structure of the first substrate in Embodiment Two of the present application;

[0041] Figure 21 is a schematic diagram of a structure of the reflective display device in an initial state in Embodiment Three of the present application;

[0042] Figure 22 is a schematic diagram of a planar structure of the first substrate in Embodiment Three of the present application. DETAILED DESCRIPTION

[0043] To further illustrate the technical means and effects adopted by the present application to achieve the intended purposes, the specific embodiments, structures, features and effects of the reflective display panel and the reflective display device according to the present application are described in detail below in combination with the drawings and preferred embodiments:

[0044] [Embodiment One]

[0045] Figure 2 is a schematic diagram of a structure of the reflective display device in an initial state in Embodiment One of the present application. Figure 3 is a schematic diagram of a planar structure of the first substrate in Embodiment One of the present application. Figure 4 is a schematic diagram of a planar structure of the second substrate in Embodiment One of the present application.

[0046] As shown in Figures 2 to 4 Embodiment One of the present application provides a reflective display panel 10, which includes a first substrate 11, a second substrate 12 arranged opposite to the first substrate 11, and a cholesteric liquid crystal layer 13 located between the first substrate 11 and the second substrate 12. All cholesteric liquid crystal molecules in the cholesteric liquid crystal layer 13 reflect blue light in a reflective state. The first substrate 11 is located on a side of the reflective display panel 10 close to an external environment, and the second substrate 12 is located on a side of the reflective display panel 10 away from the external environment, i.e., ambient light enters the reflective display panel 10 from the first substrate 11. The reflective display panel 10 has a plurality of pixel units P arranged in an array. The first substrate 11 is provided with a black matrix 111, a color resistance layer 112, and a light excitation layer 113. The black matrix 111 separates the plurality of pixel units P from each other. The light excitation layer 113 can absorb blue light and excite light corresponding to the color of the light excitation layer 113. The color resistance layer 112 and the light excitation layer 113 overlap with each other in a projection on the first substrate 11. The color resistance layer 112 is arranged on a side of the light excitation layer 113 away from the cholesteric liquid crystal layer 13. The first substrate 11 is provided with a light filtering area F and a light transmitting area T. The color resistance layer 112 and the light excitation layer 113 are stacked on each other in the light filtering area F. The first substrate 11 is in a transparent state in the light transmitting area T, for example, the first substrate 11 in the light transmitting area T can be filled with a planar layer (OC material).

[0047] When the cholesteric liquid crystal molecules in the cholesteric liquid crystal layer 13 are in the reflection state, all the cholesteric liquid crystal molecules in the cholesteric liquid crystal layer 13 present a flat posture, the cholesteric liquid crystal layer 13 reflects blue light, and part of the reflected blue light can excite light corresponding to the color of the light excitation layer 113 after passing through the light excitation layer 113, and then pass through the color resistance layer 112 to filter light, so that the chroma is better; another part of the reflected blue light can be directly emitted from the light transmission area T, and the blue light emitted from the light transmission area T and the colored light excited by the light excitation layer 113 are mixed with each other, so that light of multiple colors can be presented. When the cholesteric liquid crystal molecules in the cholesteric liquid crystal layer 13 are in the transparent state, the incident light directly passes through the cholesteric liquid crystal layer 13, so that black is presented; and the color resistance layer 112 can prevent ambient light from directly irradiating the light excitation layer 113, so as to avoid that the light excitation layer 113 directly excites light by using ambient light, thereby affecting the brightness of the pixel unit P in the screen-off or black state.

[0048] Further, one of the first substrate 11 and the second substrate 12 is an array substrate and is provided with a pixel electrode 121, and the other is provided with a common electrode 114 matched with the pixel electrode 121. In the embodiment, the second substrate 12 is the array substrate and is provided with the pixel electrode 121, and the first substrate 11 is provided with the common electrode 114 matched with the pixel electrode 121, the pixel electrode 121 is a block electrode corresponding to the pixel unit P, and the common electrode 114 is a planar electrode covering the first substrate 11.

[0049] The cholesteric liquid crystal molecules in the cholesteric liquid crystal layer 13 have three stable textures of P state (Planar, planar texture state, reflection state), FC state (Focal Conic, focal conic state, fog state) and H state (transparent state). When the cholesteric liquid crystal molecules are in the P state, the reflection spectrum of the cholesteric liquid crystal molecules is in the visible spectrum, the cholesteric liquid crystal molecules reflect bright colored light, and the specific reflected color can be set according to the pitch of the cholesteric liquid crystal molecules; when the cholesteric liquid crystal molecules are in the FC state, the cholesteric liquid crystal molecules no longer reflect the above-mentioned colored light, and the light can be scattered and transmitted through the cholesteric liquid crystal molecules; when the cholesteric liquid crystal molecules are in the H state, the cholesteric liquid crystal molecules no longer reflect the above-mentioned colored light, and the light can directly pass through the cholesteric liquid crystal molecules and has no scattering effect on the light. Under the action of a certain electric field, the three states can be converted into each other.

[0050] Figure 5 is a schematic diagram of the principle of the transformation of the three states of the cholesteric liquid crystal molecules in the embodiment one of the present application, Figure 6 is a schematic diagram of the driving signal of the transformation of the three states of the cholesteric liquid crystal molecules in the embodiment one of the present application. As Figure 5 and Figure 6As shown, the common voltage signal Vcom is applied to the common electrode 114, the first electric signal V1 is continuously applied to the pixel electrode 121, and the common voltage signal Vcom has a voltage difference (about 20V) with the first electric signal V1, so that a strong vertical electric field is formed between the common electrode 114 and the pixel electrode 121, and the cholesteric liquid crystal molecules in the cholesteric liquid crystal layer 13 rotate and stop at the H state (transparent state). The common voltage signal Vcom is applied to the common electrode 114, and the second electric signal V2 is applied to the pixel electrode 121, the second electric signal V2 has a voltage difference (for example, 20V) with the common voltage signal Vcom, and the second electric signal V2 gradually becomes the same as the common voltage signal Vcom within a first preset time, that is, the second electric signal V2 first has a large voltage difference with the common voltage signal Vcom, and then slowly decreases and becomes the same as the common voltage signal Vcom; therefore, a strong vertical electric field is first formed between the common electrode 114 and the pixel electrode 121, and then the vertical electric field slowly disappears, so that the cholesteric liquid crystal molecules in the cholesteric liquid crystal layer 13 rotate and stop at the FC state, which is a scattering state and has a scattering effect. The common voltage signal Vcom is applied to the common electrode 114, and the third electric signal V3 is applied to the pixel electrode 121, the third electric signal V3 has a voltage difference (for example, 30V) with the common voltage signal Vcom, and the third electric signal V3 directly becomes the same as the common voltage signal Vcom within a second preset time, and the second preset time is less than the first preset time, that is, the third electric signal V3 first has a large voltage difference with the common voltage signal Vcom, and then quickly decreases and becomes the same as the common voltage signal Vcom; therefore, a strong vertical electric field is first formed between the common electrode 114 and the pixel electrode 121, and then the vertical electric field quickly disappears, so that the cholesteric liquid crystal molecules in the cholesteric liquid crystal layer 13 rotate and stop at the P state, which is a reflection state. The arrangement direction of the cholesteric liquid crystal molecules is different, the reflected visible light spectrum is different, and the remaining spectrum is transmitted, and the P state and the FC state do not need voltage to be maintained.

[0051] The reflection spectrum band (Δλ) of the cholesteric liquid crystal molecules is proportional to the helical moment (Po) and the birefringence (Δn) of the cholesteric liquid crystal molecules, and the formula is: Δλ=PoΔn; the reflection spectrum wavelength (λ) of the cholesteric liquid crystal molecules is proportional to the helical moment (Po) and the average birefringence (n) of the cholesteric liquid crystal molecules, and the formula is: λ=nPo. Therefore, the cholesteric liquid crystal molecules with different pitches can reflect different colors of light in the reflection state. The cholesteric liquid crystal molecules reflect blue light in the reflection state, for example, can reflect high-band blue light, and the wavelength range of the reflected light is 450-500 nm. Since the blue light band in the ambient light is mainly in the 450-500 nm interval, the light excitation layer 113 excited by the blue light in this band interval can effectively utilize the ambient light excitation; moreover, the 450-500 nm band is beneficial blue light, harmless to the human eye, while the 400-450 nm band is harmful to the retina and damages the photoreceptor tissue, therefore, the cholesteric liquid crystal molecules with a wavelength range of 450-500 nm of reflected light can have a better eye protection effect.

[0052] Further, the light ray excitation layer 113 adopts quantum dot material, quantum dot (QD for short), which is usually a kind of nanoparticle composed of II-VI or III-V elements, with a size less than or close to the exciton Bohr radius (generally not more than 10 nm in diameter), and has obvious quantum effect. It is generally believed that it is a quasi-zero-dimensional material, which binds the conduction band electrons, valence band holes and excitons in three spatial directions. When the particle size of the nanomaterial decreases to a certain value (generally below 10 nm), the energy level near the metal Fermi level changes from quasi-continuous to discrete energy level, the energy gap of the discontinuous highest occupied molecular orbital and the lowest unoccupied molecular orbital of the nanometer semiconductor microparticle is widened, thereby causing the blue shift of the absorption and fluorescence spectrum peak, which is called quantum size effect. Quantum size effect makes the photoelectric properties of semiconductor quantum dots change greatly. When the size of semiconductor quantum dot particles is less than the Bohr radius of the exciton, the quantum size effect changes the energy level structure of the semiconductor material, which changes from a continuous energy band structure to a discrete energy level structure with molecular properties. Using this phenomenon, different particle sizes of semiconductor quantum dots can be prepared in the same reaction, producing light emission of different frequencies, so that a variety of light colors can be conveniently controlled. The energy of the solid absorbed photon (absorption) will be greater than that of the radiated photon (emission), so the emission spectrum will shift to the lower energy direction (red shift) compared with the absorption spectrum. The difference between the two photon energies is called Stokes shift. Because the quantum dot emission spectrum is narrow and the light emission efficiency is high, and has quantum size effect and Stokes shift effect, the corresponding quantum dots in each color sub-pixel can absorb the light emitted by the backlight source with energy greater than the color energy of the sub-pixel unit, and efficiently convert the absorbed part of the light into monochromatic light of the sub-pixel unit color and emit it out, so that the corresponding color of the color sub-pixel is more pure, with higher saturation, and the transmittance of the light source can be improved. Without reducing the quantum yield of quantum dots, SiO2-coated CH3NH3PbBr3 quantum dots (MAPB-QDs / SiO2) are prepared, and the light stability test shows that the photoluminescence rate (PL) of the MAPB-QD / SiO2 powder maintains 94.10% after 7h of LED irradiation at a wavelength of about 470nm.

[0053] Of course, the light excitation layer 113 can also use fluorescent material, the principle of light emission of fluorescent material is mainly achieved through fluorescence effect. When the fluorescent powder is irradiated by ultraviolet or blue light, the internal atoms or molecules will absorb the energy of photons, and the electrons will jump to the excited state to form excited state electrons. The excited state electrons are not stable and will de-excite in a very short time and return to the ground state. In this process, the electrons release energy, which is released in the form of photons to form visible light. White light is produced by exciting red, green, or yellow fluorescent powder with blue light. pc-wLEDs prepared using a 460 nm blue In-GaN LED chip and cerium ion (III) doped yttrium aluminum garnet (Y3Al5O12: Ce3+, abbreviated as YAG: Ce3+) fluorescent powder have been commercialized.

[0054] As shown in Figure 4 The second substrate 12 is provided with a plurality of scanning lines and a plurality of data lines, and the plurality of scanning lines and the plurality of data lines are insulated and crossed to define a plurality of pixel units P. The second substrate 12 is provided with a thin film transistor and a pixel electrode 121 in each pixel unit P, and the pixel electrode 121 is electrically connected to the adjacent scanning line and data line through the thin film transistor. The thin film transistor includes a gate, an active layer, a drain and a source. The gate is located in the same layer as the scanning line and is electrically connected. The gate is insulated from the active layer by an insulating layer. The source is electrically connected to the data line. The drain is electrically connected to the pixel electrode 121 through a contact hole.

[0055] Further, the color resistance layer 112 and the light excitation layer 113 that overlap each other have the same color. In the embodiment, the plurality of pixel units P include a first pixel unit P1 and a second pixel unit P2, and the first pixel unit P1 and the second pixel unit P2 are arranged alternately in the row direction. The color resistance layer 112 includes a red color resistance layer 112r and a green color resistance layer 112g, and the light excitation layer 113 includes a red light excitation layer 113r and a green light excitation layer 113g. The red color resistance layer 112r and the red light excitation layer 113r are stacked in the first pixel unit P1, and the green color resistance layer 112g and the green light excitation layer 113g are stacked in the second pixel unit P2. That is, the projections of the red color resistance layer 112r and the red light excitation layer 113r on the first substrate 11 overlap each other, and the projections of the green color resistance layer 112g and the green light excitation layer 113g on the first substrate 11 overlap each other.

[0056] The red quantum dots have a size of 7 nm, the green quantum dots have a size of 3 nm, and the blue quantum dots have a size of 2 nm. Utilizing the size effect and Stokes spectral shift effect of quantum dots, the red quantum dots can absorb light emitted from a light source with energy greater than red light energy, convert it into monochromatic red light, and then emit it, resulting in a purer red color. Similarly, the green quantum dots can absorb light emitted from a light source with energy greater than green light energy, convert it into monochromatic green light, and then emit it, resulting in a purer green color. The blue quantum dots can absorb light emitted from a light source with energy greater than blue light energy (e.g., ultraviolet light), convert it into monochromatic blue light, and then emit it. Because the blue quantum dots are small, they are very fragile and difficult to process. This application uses cholesteric liquid crystal molecules that reflect blue light in their reflective state, which not only allows the red and green quantum dots to excite light of the corresponding colors but also avoids the use of blue quantum dots, thus reducing the complexity of the manufacturing process.

[0057] In this embodiment, as Figure 3 As shown, each pixel unit P has a filter area F and a light-transmitting area T. Optionally, the filter area F in each pixel unit P is located on both sides of the light-transmitting area T. For example, each pixel unit P has two filter areas F and one light-transmitting area T, with the two filter areas F located on the left and right sides of the light-transmitting area T, respectively. Within each pixel unit P, the ratio of filter area F:light-transmitting area T:filter area F = 0.5:1:0.5 (the width ratio can be adjusted according to the required contrast ratio / NTSC, etc.).

[0058] In this embodiment, a light-absorbing layer 14 is provided on the second substrate 12. The light-absorbing layer 14 is used to absorb light passing through the cholesteric liquid crystal layer 13, thereby making the pixel unit P have lower brightness in the black state. The light-absorbing layer 14 is disposed on the side of the second substrate 12 away from the cholesteric liquid crystal layer 13.

[0059] This application also provides a reflective display device, including the reflective display panel 10 as described above.

[0060] Furthermore, the reflective display device also includes a side-lit light source module 20, which is disposed on the side of the first substrate 11 away from the cholesteric liquid crystal layer 13 and is used to provide a light source toward the cholesteric liquid crystal layer 13. The side-lit light source module 20 includes a light source 21 and a light guide plate 22. The light source 21 is disposed on the side of the light guide plate 22, which has multiple light-guiding dots for reflecting the light emitted by the light source 21 into the reflective display panel 10. Optionally, the light source 21 provides a white light source, preferably with a blue light wavelength of 450–500 nm, and the light-guiding dots are disposed on the surface of the light guide plate 22 away from the reflective display panel 10.

[0061] Figure 7is a structural schematic diagram of the reflective display device in the embodiment one of the present application when displaying black and white picture by using ambient light. As shown in Figure 7 When the reflective display device displays black and white picture by using ambient light, the side-in light source module 20 is closed, the cholesteric liquid crystal molecules in the corresponding area of the first pixel unit P1 and the second pixel unit P2 in the white picture area are controlled to be in the reflective state, the first pixel unit P1 can reflect blue light and red light, the second pixel unit P2 can reflect blue light and green light, and the red light, the green light and the blue light are mixed to white light; the cholesteric liquid crystal molecules in the corresponding area of the first pixel unit P1 and the second pixel unit P2 in the black picture area are controlled to be in the transmissive state (for example, the fog state, the FC state; or the transparent state, the H state), and the light is absorbed by the light absorbing layer 14 after passing through the cholesteric liquid crystal layer 13, so as to present black state.

[0062] Figure 8 is a structural schematic diagram of the reflective display device in the embodiment one of the present application when displaying purple black picture by using ambient light. As shown in Figure 8 When the reflective display device displays purple black picture by using ambient light, the side-in light source module 20 is closed, the cholesteric liquid crystal molecules in the corresponding area of the first pixel unit P1 in the purple picture area are controlled to be in the reflective state, the first pixel unit P1 can reflect blue light and red light, and the red light and the blue light are mixed to purple light (magenta light, also known as fuchsia light, i.e. lighter purple red); the cholesteric liquid crystal molecules in the corresponding area of the first pixel unit P1 and the second pixel unit P2 in the black picture area are controlled to be in the transmissive state (for example, the fog state, the FC state; or the transparent state, the H state), and the light is absorbed by the light absorbing layer 14 after passing through the cholesteric liquid crystal layer 13, so as to present black state.

[0063] Figure 9 is a structural schematic diagram of the reflective display device in the embodiment one of the present application when displaying cyan black picture by using ambient light. As shown in Figure 9 When the reflective display device displays cyan black picture by using ambient light, the side-in light source module 20 is closed, the cholesteric liquid crystal molecules in the corresponding area of the second pixel unit P2 in the cyan picture area are controlled to be in the reflective state, the second pixel unit P2 can reflect blue light and green light, and the green light and the blue light are mixed to cyan light; the cholesteric liquid crystal molecules in the corresponding area of the first pixel unit P1 and the second pixel unit P2 in the black picture area are controlled to be in the transmissive state (for example, the fog state, the FC state; or the transparent state, the H state), and the light is absorbed by the light absorbing layer 14 after passing through the cholesteric liquid crystal layer 13, so as to present black state.

[0064] Figure 10 is a structural schematic diagram of the reflective display device in the embodiment one of the present application when displaying purple gray picture by using ambient light. As shown in Figure 10As shown, when the reflective display device displays a purple gray picture by using ambient light, the edge-lit light source module 20 is turned off, the cholesteric phase liquid crystal molecules in the area corresponding to the first pixel unit P1 in the purple picture area are controlled to be in the reflective state, the first pixel unit P1 can reflect blue light and red light, and the red light and the blue light are mixed to be purple light (magenta light, also known as fuchsia light, i.e. lighter purple red); the cholesteric phase liquid crystal molecules in the area corresponding to the first pixel unit P1 and part of the second pixel unit P2 in the gray picture area are controlled to be in the reflective state, the first pixel unit P1 can reflect blue light and red light, the second pixel unit P2 can reflect blue light and green light, the red light, the green light and the blue light are mixed to be white light, and the cholesteric phase liquid crystal molecules in the area corresponding to another part of the second pixel unit P2 in the gray picture area are controlled to be in the transmissive state (for example, in the FC state or in the H state), the light passes through the cholesteric phase liquid crystal layer 13 and is absorbed by the light absorbing layer 14, so as to present a black state, and the white light and the black state are mixed to be gray or gray black in the gray picture area.

[0065] Figure 11 FIG. 6 is a structure schematic diagram of the reflective display device in the embodiment one of the present application when the reflective display device displays a cyan gray picture by using ambient light. As shown in the figure, Figure 11 As shown, when the reflective display device displays a cyan gray picture by using ambient light, the edge-lit light source module 20 is turned off, the cholesteric phase liquid crystal molecules in the area corresponding to the second pixel unit P2 in the cyan picture area are controlled to be in the reflective state, the second pixel unit P2 can reflect blue light and green light, and the green light and the blue light are mixed to be cyan light; the cholesteric phase liquid crystal molecules in the area corresponding to part of the first pixel unit P1 and the second pixel unit P2 in the gray picture area are controlled to be in the reflective state, the first pixel unit P1 can reflect blue light and red light, the second pixel unit P2 can reflect blue light and green light, the red light, the green light and the blue light are mixed to be white light, and the cholesteric phase liquid crystal molecules in the area corresponding to another part of the first pixel unit P1 in the gray picture area are controlled to be in the transmissive state (for example, in the FC state or in the H state), the light passes through the cholesteric phase liquid crystal layer 13 and is absorbed by the light absorbing layer 14, so as to present a black state, and the white light and the black state are mixed to be gray or gray black in the gray picture area.

[0066] Figure 12 FIG. 7 is a structure schematic diagram of the reflective display device in the embodiment one of the present application when the reflective display device displays a black and white picture by using the edge-lit light source. As shown in the figure, Figure 12As shown, when the reflective display device displays a black and white picture using the edge-lit light source, the edge-lit light source module 20 is turned on, the cholesteric liquid crystal molecules in the corresponding region of the first pixel unit P1 and the second pixel unit P2 in the white picture region are controlled to be in the reflective state, the first pixel unit P1 can reflect blue light and red light, the second pixel unit P2 can reflect blue light and green light, and white light is obtained by mixing the red light, the green light and the blue light; the cholesteric liquid crystal molecules in the corresponding region of the first pixel unit P1 and the second pixel unit P2 in the black picture region are controlled to be in the transmissive state (for example, the FC state or the H state), and the light is absorbed by the light absorbing layer 14 after passing through the cholesteric liquid crystal layer 13, so as to present a black state.

[0067] Figure 13 FIG. 3 is a structural schematic diagram of the reflective display device in the embodiment one of the present application when displaying a purple and black picture using the edge-lit light source. Figure 13 As shown, when the reflective display device displays a purple and black picture using the edge-lit light source, the edge-lit light source module 20 is turned on, the cholesteric liquid crystal molecules in the corresponding region of the first pixel unit P1 in the purple picture region are controlled to be in the reflective state, the first pixel unit P1 can reflect blue light and red light, and purple light (magenta light, also known as fuchsia light, i.e., lighter purple red) is obtained by mixing the red light and the blue light; the cholesteric liquid crystal molecules in the corresponding region of the first pixel unit P1 and the second pixel unit P2 in the black picture region are controlled to be in the transmissive state (for example, the FC state or the H state), and the light is absorbed by the light absorbing layer 14 after passing through the cholesteric liquid crystal layer 13, so as to present a black state.

[0068] Figure 14 FIG. 4 is a structural schematic diagram of the reflective display device in the embodiment one of the present application when displaying a cyan and black picture using the edge-lit light source. Figure 14 As shown, when the reflective display device displays a cyan and black picture using the edge-lit light source, the edge-lit light source module 20 is turned on, the cholesteric liquid crystal molecules in the corresponding region of the second pixel unit P2 in the cyan picture region are controlled to be in the reflective state, the second pixel unit P2 can reflect blue light and green light, and cyan light is obtained by mixing the green light and the blue light; the cholesteric liquid crystal molecules in the corresponding region of the first pixel unit P1 and the second pixel unit P2 in the black picture region are controlled to be in the transmissive state (for example, the FC state or the H state), and the light is absorbed by the light absorbing layer 14 after passing through the cholesteric liquid crystal layer 13, so as to present a black state.

[0069] Figure 15 FIG. 5 is a structural schematic diagram of the reflective display device in the embodiment one of the present application when displaying a purple and gray picture using the edge-lit light source. Figure 15As shown, when the reflective display device displays a purple gray picture by using the edge-lit light source, the edge-lit light source module 20 is turned on, the cholesteric liquid crystal molecules in the area corresponding to the first pixel unit P1 in the purple picture area are controlled to be in the reflective state, the first pixel unit P1 can reflect blue light and red light, and the red light and the blue light are mixed to be purple light (magenta light, also known as fuchsia light, i.e. lighter purple red); the cholesteric liquid crystal molecules in the area corresponding to the first pixel unit P1 and part of the second pixel unit P2 in the gray picture area are controlled to be in the reflective state, the first pixel unit P1 can reflect blue light and red light, the second pixel unit P2 can reflect blue light and green light, the red light, the green light and the blue light are mixed to be white light, and the cholesteric liquid crystal molecules in the area corresponding to another part of the second pixel unit P2 in the gray picture area are controlled to be in the transmissive state (for example, the FC state or the H state), the light passes through the cholesteric liquid crystal layer 13 from the second pixel unit P2 and is absorbed by the light absorbing layer 14, so as to present a black state, and the white light and the black state are mixed to be gray or gray black in the gray picture area.

[0070] Figure 16 FIG. 2 is a structure schematic diagram when the reflective display device displays a cyan gray picture by using the edge-lit light source in the embodiment one of the present application. As shown, Figure 16 As shown, when the reflective display device displays a cyan gray picture by using the edge-lit light source, the edge-lit light source module 20 is turned on, the cholesteric liquid crystal molecules in the area corresponding to the second pixel unit P2 in the cyan picture area are controlled to be in the reflective state, the second pixel unit P2 can reflect blue light and green light, and the green light and the blue light are mixed to be cyan light; the cholesteric liquid crystal molecules in the area corresponding to part of the first pixel unit P1 and the second pixel unit P2 in the gray picture area are controlled to be in the reflective state, the first pixel unit P1 can reflect blue light and red light, the second pixel unit P2 can reflect blue light and green light, the red light, the green light and the blue light are mixed to be white light, and the cholesteric liquid crystal molecules in the area corresponding to another part of the first pixel unit P1 in the gray picture area are controlled to be in the transmissive state (for example, the FC state or the H state), the light passes through the cholesteric liquid crystal layer 13 from the first pixel unit P1 and is absorbed by the light absorbing layer 14, so as to present a black state, and the white light and the black state are mixed to be gray or gray black in the gray picture area.

[0071] Figure 17 FIG. 3 is an incident light principle schematic diagram of the filter area in the embodiment one of the present application. As shown, Figure 17As shown, when the pixel unit P is in the screen-off or black state, the incident light first passes through the color resistance layer 112 and is filtered, the filtered light cannot make the light excitation layer 113 excite light, and then passes through the light excitation layer 113 and the cholesteric liquid crystal layer 13 and is absorbed by the light absorption layer 14, thereby presenting black color, so as to reduce the brightness of the pixel unit P in the screen-off or black state. Since the incident light is mixed with blue light, if the color resistance layer 112 is not provided, the incident light will make the light excitation layer 113 excite light after being incident on the light excitation layer 113, which has a certain brightness, and will affect the brightness of the pixel unit P in the screen-off or black state, and affect the contrast.

[0072] Figure 18 is a schematic diagram of the principle of reflected light of the light filtering area of the reflective display device in the embodiment one of the present application. For the light filtering area F, as shown, since the utilization rate of the blue light by the light excitation layer 113 cannot reach 100%, there are still some blue light not utilized mixed in the light emitted from the light excitation layer 113; by setting the color resistance layer 112, the blue light not utilized by the light excitation layer 113 can also be filtered out, so as to improve the color purity of the light. Figure 18

[0073] [Embodiment two]

[0074] Figure 19 is a schematic diagram of the structure of the reflective display device in the initial state in the embodiment two of the present application. Figure 20 is a schematic diagram of the planar structure of the first substrate in the embodiment two of the present application. As shown in Figure 19 and Figure 20 , the reflective display panel and the reflective display device provided in the embodiment two of the present application are basically the same as those in the embodiment one of the present application, and the difference lies in that, in the present embodiment: Figures 2 to 18

[0075] The light filtering area F and the light transmission area T are arranged in each pixel unit P. Optionally, the light filtering area F in each pixel unit P is arranged at one side of the pixel unit P, and the light transmission area T is arranged at the other side of the pixel unit P, for example, one light filtering area F and one light transmission area T are arranged in each pixel unit P, the light filtering area F is arranged in the right half region of the pixel unit P, and the light transmission area T is arranged in the left half region of the pixel unit P. For each pixel unit P, the light filtering area F:light transmission area T=1.5:1 (the width ratio can be adjusted according to the required contrast / NTSC, etc.).

[0076] ​​In this embodiment, each pixel unit P is provided with a light-shielding barrier 115. The light-shielding barrier 115 in each pixel unit P is located between the light-filtering area F and the light-transmitting area T and is used to separate the light-filtering area F and the light-transmitting area T from each other. The light-shielding barrier 115 can be made of the same material and using the same manufacturing process as the black matrix 111.

[0077] 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.

[0078] [Example 3]

[0079] Figure 21 This is a schematic diagram of the reflective display device in its initial state according to Embodiment 3 of the present invention. Figure 22 This is a schematic diagram of the planar structure of the first substrate in Embodiment 3 of the present invention. Figure 21 and Figure 22 As shown, the reflective display panel and reflective display device provided in Embodiment 3 of the present invention are similar to those in Embodiment 1. Figures 2 to 18 The reflective display panel and reflective display device in this embodiment are basically the same, except that in this embodiment:

[0080] Multiple pixel units P include a first pixel unit P1, a second pixel unit P2, and a third pixel unit P3. A filter area F corresponds to the first pixel unit P1 and the second pixel unit P2, and a light-transmitting area T corresponds to the third pixel unit P3. That is, the first pixel unit P1 is entirely the filter area F, the second pixel unit P2 is entirely the filter area F, and the third pixel unit P3 is entirely the light-transmitting area T. The color resist layer 112 includes a red resist layer 112r and a green color resist layer 112g, and the light excitation layer 113 includes a red light excitation layer 113r and a green light excitation layer 113g. A red resist layer 112r and a red light excitation layer 113r are stacked within the first pixel unit P1, and a green resist layer 112g and a green light excitation layer 113g are stacked within the second pixel unit P2. That is, the projections of the red resist layer 112r and the red light excitation layer 113r onto the first substrate 11 overlap, and the projections of the green resist layer 112g and the green light excitation layer 113g onto the first substrate 11 also overlap. In this embodiment, the first pixel unit P1 is a red pixel unit that reflects red light, the second pixel unit P2 is a green pixel unit that reflects green light, and the third pixel unit P3 is a blue pixel unit that reflects blue light. This allows the reflection of red, green, and blue light to be controlled individually, mixing more colors of light to enhance the color of the displayed image.

[0081] Further, the third pixel unit P3 is arranged between the first pixel unit P1 and the second pixel unit P2.

[0082] Those skilled in the art should understand that the remaining structure and working principle of the embodiment are the same as those of the first embodiment, and will not be repeated here.

[0083] In this document, the terms of up, down, left, right, front, back and the like are defined according to the position of the structure in the drawing and the position of the structure relative to each other, only to express the technical solution clearly and conveniently. It should be understood that the use of the terms should not limit the scope of the application. It should also be understood that the terms "first" and "second" used herein are only used for name distinction, and do not limit the quantity and order.

[0084] The above is only the preferred embodiment of the present application, not any form of limitation on the present application, although the present application has been disclosed as above, however, not to limit the present application, any skilled in the art, without departing from the scope of the present application, can make some changes or modifications to the above disclosed technical content, for equivalent embodiments of equivalent changes, but as long as it does not deviate from the technical solution of the present application, according to the technical essence of the present application, any simple modification, equivalent change and modification of the above embodiment, all still belong to the protection scope of the present application technical solution.

Claims

1. A reflective display panel, characterized by The display panel comprises a first substrate (11), a second substrate (12) arranged opposite to the first substrate (11), and a cholesteric liquid crystal layer (13) between the first substrate (11) and the second substrate (12), all cholesteric liquid crystal molecules in the cholesteric liquid crystal layer (13) reflect blue light in a reflection state, one of the first substrate (11) and the second substrate (12) is an array substrate and is provided with a pixel electrode (121), and the other is provided with a common electrode (114) matched with the pixel electrode (121). The reflective display panel has a plurality of pixel units (P) arranged in an array, the first substrate (11) is provided with a black matrix (111), a color resistance layer (112), and a light excitation layer (113), the black matrix (111) separates the plurality of pixel units (P) from each other, the light excitation layer (113) can absorb blue light and excite light corresponding to the color of the light excitation layer (113), the projection of the color resistance layer (112) and the light excitation layer (113) on the first substrate (11) overlaps each other, and the color resistance layer (112) is arranged on the side of the light excitation layer (113) away from the cholesteric liquid crystal layer (13). The first substrate (11) is provided with a light filtering area (F) and a light transmission area (T), the color resistance layer (112) and the light excitation layer (113) are stacked with each other in the light filtering area (F), and the first substrate (11) is in a transparent state in the light transmission area (T). Each of the pixel units (P) is provided with the light filtering area (F) and the light transmission area (T).

2. The reflective display panel of claim 1, wherein, The plurality of pixel units (P) comprises a first pixel unit (P1) and a second pixel unit (P2), the color resistance layer (112) comprises a red color resistance layer (112r) and a green color resistance layer (112g), the light excitation layer (113) comprises a red light excitation layer (113r) and a green light excitation layer (113g), the red color resistance layer (112r) and the red light excitation layer (113r) are stacked with each other in the first pixel unit (P1), and the green color resistance layer (112g) and the green light excitation layer (113g) are stacked with each other in the second pixel unit (P2).

3. The reflective display panel of claim 1, wherein, The light filtering area (F) in each of the pixel units (P) is arranged on both sides of the light transmission area (T). Alternatively, the light filtering area (F) in each of the pixel units (P) is arranged on one side of the pixel unit (P), and the light transmission area (T) is arranged on the other side of the pixel unit (P).

4. The reflective display panel of claim 1, wherein, Each of the pixel units (P) is provided with a light shielding barrier (115), and the light shielding barrier (115) in each of the pixel units (P) is arranged between the light filtering area (F) and the light transmission area (T) and used to separate the light filtering area (F) and the light transmission area (T) from each other.

5. The reflective display panel according to any of claims 1-4, characterized in that, The second substrate (12) is provided with an absorbing layer (14), and the absorbing layer (14) is used to absorb light passing through the cholesteric liquid crystal layer (13).

6. A reflective display device, characterized by The reflective display panel (10) comprises a reflective display panel (10) according to any one of claims 1-5.

7. The reflective display device of claim 6, wherein The reflective display device further comprises a side-in light source module (20) arranged on a side of the first substrate (11) away from the cholesteric liquid crystal layer (13) and configured to provide a light source toward a side of the cholesteric liquid crystal layer (13).

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