Optical filter, display assembly, and electronic device

Abstract

This application provides a light filter, a display component, and an electronic device. The light filter includes a substrate and a filter stack located on one side of the substrate. The filter stack includes at least three stacked dielectric layer groups, each dielectric layer group consisting of one or more refractive dielectric layers. One of the refractive dielectric layers in at least one dielectric layer group includes a first refractive dielectric layer. The refractive index of the first refractive dielectric layer is greater than 1.1 and less than 1.35, or equal to 1.1, or equal to 1.35. The low refractive index of the first refractive dielectric layer can compensate for the transmittance and color purity of light incident at large angles. The dielectric layer groups in the filter stack constitute a Fabry-Perot cavity. Incident light of a specific wavelength band undergoes constructive interference in the Fabry-Perot cavity, increasing the transmittance of the incident light in that wavelength band. The filter provided by this application can increase the overall transmittance and color purity of incident light, thereby improving the brightness and color gamut of the electronic device and enhancing the display effect.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a filter, display component and electronic device. Background Technology

[0002] With the rapid development of display technology, users have increasingly higher requirements for the color display effect of display devices. In display devices, filters enable the display device to display colors by allowing light of a specific wavelength to pass through; therefore, the color display effect is closely related to the filter.

[0003] Currently, in related technologies, filters are usually made by mixing organic dyes with photoresist, which is low in cost and simple in process. However, such filters have poor wavelength selectivity, low transmittance and color purity, thus affecting the performance of display devices in terms of brightness and color gamut. Summary of the Invention

[0004] This application provides a filter, display component, and electronic device that can improve brightness and color gamut.

[0005] In a first aspect, this application provides a filter, including a substrate and a filter stack located on one side of the substrate. The filter stack includes at least three stacked dielectric layer groups, each of the dielectric layer groups consisting of one or more refractive dielectric layers. Specifically, at least one of the refractive dielectric layers in at least one of the dielectric layer groups includes a first refractive dielectric layer, the refractive index of which is greater than 1.1 and less than 1.35, or equal to 1.1, or equal to 1.35.

[0006] In this implementation, the filter stack is located on one side of the substrate along the thickness direction, and multiple dielectric layer groups in the filter stack are also stacked along the thickness direction. Light is incident from the side of the substrate away from the filter stack along the thickness direction, and then sequentially passes through the multiple dielectric layer groups in the filter stack. At least three dielectric layer groups in the filter stack constitute a Fabry-Perot cavity (hereinafter referred to as Fabry-Perot cavity). The incident light is reflected multiple times in the Fabry-Perot cavity, and the reflected light interferes. Light of a specific wavelength can undergo constructive interference in the Fabry-Perot cavity, allowing the filter to select the wavelength of the incident non-monochromatic light and improve monochromaticity. In particular, when multiple beams of light with a phase difference of 2π after multiple reflections in the Fabry-Perot cavity are superimposed, the intensity of the light emitted from the Fabry-Perot cavity increases, thereby improving the transmittance.

[0007] In this implementation, at least one of the refractive medium layers in the dielectric layer group includes a first refractive medium layer. The refractive index of the first refractive medium layer is greater than 1.1 and less than 1.35, or equal to 1.1, or equal to 1.35. The smaller refractive index of the first refractive medium layer can compensate for the transmittance and color purity of the incident light at a large angle to a certain extent, thereby improving the overall light output effect of the incident light in the filter.

[0008] Furthermore, while a higher refractive index in the first refractive medium layer might improve the extraction efficiency of light incident at large angles, it could simultaneously reduce the extraction efficiency of light incident at small angles, thus affecting the overall extraction efficiency. Moreover, replacing the first refractive medium layer with a high-refractive-index layer presents challenges in achieving precise adjustment. Because the high-refractive-index layer has a larger refractive index, maintaining the same phase difference as the lower-refractive-index first layer requires making it much thinner, increasing the manufacturing complexity.

[0009] In this application, by setting a filter: first, at least three dielectric layers in the filter form a Fabry-Perot cavity, which can filter light of a specific wavelength band, optimize the color purity of the emitted light, and thus improve the color gamut of the electronic device.

[0010] Secondly, by setting a first refractive medium layer with a low refractive index in the filter, the light extraction efficiency of light incident at large angles can be compensated, and the light extraction efficiency of light incident at small angles has minimal impact. Therefore, the overall light extraction efficiency reduction caused by angle changes can be reduced, thereby improving the brightness of electronic devices.

[0011] Third, setting a first refractive medium layer with a low refractive index in the filter can improve the adjustment accuracy of the filter and reduce the difficulty of the process.

[0012] In one implementation, the substrate can be a transparent substrate, preferably glass. This solution helps to reduce the loss of incident light in the substrate.

[0013] In one implementation, the at least three dielectric layer groups include four dielectric layer groups, the four dielectric layer groups including a first dielectric layer group, a second dielectric layer group, a third dielectric layer group and a fourth dielectric layer group stacked sequentially, the first dielectric layer group being closer to the substrate than the fourth dielectric layer group, and the fourth dielectric layer group including the first refractive dielectric layer.

[0014] In this implementation, the first dielectric layer group, the second dielectric layer group, the third dielectric layer group, and the fourth dielectric layer group together constitute a Fabry-Perot cavity. The first dielectric layer group is equivalent to one of the parallel plates of the Fabry-Perot cavity, the third dielectric layer group and the fourth dielectric layer group are equivalent to the other parallel plate of the Fabry-Perot cavity, and the second dielectric layer group is equivalent to the reflecting cavity of the Fabry-Perot cavity. The incident light undergoes multiple reflections in the reflecting cavity, and the light with a phase difference of 2π undergoes constructive interference, thereby comprehensively improving the overall light output efficiency of the filter.

[0015] In this implementation, the fourth dielectric layer group is located on the side of the third dielectric layer group away from the substrate along the thickness direction. That is, after incident light enters from the substrate, it sequentially passes through the first dielectric layer group, the second dielectric layer group, the third dielectric layer group, and the fourth dielectric layer group containing the first refractive dielectric layer. The fourth dielectric layer group serves as the optical output end of the filter stack. A first refractive dielectric layer is disposed at the optical output end. Because the refractive index of the first refractive dielectric layer is low, this solution also helps to improve the light extraction efficiency of large-angle light and reduces light reflectivity, thereby increasing light transmittance.

[0016] In one implementation, the fourth dielectric layer group includes a first refractive dielectric layer and at least one of a second refractive dielectric layer and a third refractive dielectric layer, wherein the refractive index of the second refractive dielectric layer is greater than that of the first refractive dielectric layer, and the refractive index of the third refractive dielectric layer is greater than that of the second refractive dielectric layer. By incorporating multiple refractive dielectric layers in the fourth dielectric layer group, the number of reflections within the group is increased, enhancing the proportion of constructive interference light and thus improving the overall light extraction performance of the filter.

[0017] In one implementation, the first dielectric layer group and the third dielectric layer group are identical and different from the second dielectric layer group. In this implementation, the first dielectric layer group and the third dielectric layer group are identical, and they have a symmetrical structure with respect to the second dielectric layer group. The symmetrical structure can make the light transmission more stable and accurate, which is beneficial to reducing light loss.

[0018] In one implementation, the first dielectric layer group includes at least two first dielectric layer subgroups, each of which includes at least one of a first refractive medium layer, a second refractive medium layer, and a third refractive medium layer, wherein the refractive index of the second refractive medium layer is greater than the refractive index of the first refractive medium layer, and the refractive index of the third refractive medium layer is greater than the refractive index of the second refractive medium layer.

[0019] In this implementation, the first dielectric layer group serves as the optical input end of the filter stack. A first refractive dielectric layer, a second refractive dielectric layer, and a third refractive dielectric layer with different refractive indices are disposed at the optical input end. This allows the filter to flexibly incorporate dielectric layers with different refractive indices according to different light output requirements, improving the filter's practicality. The number of first dielectric layer subgroups can be determined as needed. In one implementation, when the first dielectric layer group includes two or more first dielectric layer subgroups, each first dielectric layer subgroup has the same composition, and each subgroup is sequentially stacked to form the first dielectric layer group.

[0020] In this implementation, the first dielectric layer group and the third dielectric layer group form a symmetrical structure, and the first dielectric layer group and the third dielectric layer group have the same composition. When the first dielectric layer group includes multiple first dielectric layer subgroups and the third dielectric layer group includes multiple third dielectric layer subgroups, the number of reflections of incident light in the Fabry-Perot cavity is increased, the proportion of light with constructive interference is increased, and thus the overall light output effect of the filter is improved.

[0021] For example, in one implementation, when the first dielectric layer group includes two first dielectric layer subgroups, and each first dielectric layer subgroup includes a second refractive medium layer and a third refractive medium layer, the arrangement order of the refractive medium layers in the first dielectric layer group is second refractive medium layer, third refractive medium layer, second refractive medium layer, third refractive medium layer. In another implementation, the first dielectric layer group may include only one first dielectric layer subgroup, and when the first dielectric layer subgroup includes a second refractive medium layer and a third refractive medium layer, the arrangement order of the refractive medium layers in the first dielectric layer group is second refractive medium layer, third refractive medium layer.

[0022] In one implementation, the refractive index of the second refractive medium layer is greater than or equal to 1.38 and less than or equal to 1.9, and the refractive index of the third refractive medium layer is greater than or equal to 1.8 and less than or equal to 2.76. In this implementation, the refractive indices of the second and third refractive medium layers satisfy the above range, which helps to reduce the difficulty of setting up filters with high light output.

[0023] In one implementation, the first dielectric layer subgroup includes a second refractive dielectric layer and two third refractive dielectric layers, with the two third refractive dielectric layers located on opposite sides of the second refractive dielectric layer, and the sum of the thicknesses of the two third refractive dielectric layers equal to the thickness of the second refractive dielectric layer.

[0024] In this implementation, within the first dielectric layer subgroup, the thickness of one third refractive dielectric layer is half the thickness of the second refractive dielectric layer. Since the filter stack contains numerous refractive dielectric layers, adjusting the thickness of the third refractive dielectric layer to half that of the second effectively reduces the overall thickness of the filter stack, facilitating the thinner and lighter design of electronic devices. Furthermore, compared to using a single third refractive dielectric layer with the same thickness as the second refractive dielectric layer, setting two third refractive dielectric layers with a thickness half that of the second refractive dielectric layer increases the number of reflection interfaces, increases the number of reflections, and thus increases the amount of constructive interference light, improving the light extraction efficiency of large-angle light in the filter.

[0025] In this implementation, the thickness of each dielectric layer in the filter stack is equal, which helps to reduce design complexity. In some implementations, when the target light to be transmitted by the filter stack is different, the thickness of the dielectric layer corresponding to different filter stacks is set to different values ​​as needed to ensure the transmission effect of the target light.

[0026] In one implementation, the thickness of a first refractive medium layer in the fourth dielectric layer group is equal to the thickness of a third refractive medium layer in the first dielectric layer subgroup. In this implementation, since the filter stack has a large number of refractive medium layers, adjusting the thickness of the first and third refractive medium layers to half that of the second refractive medium layer can effectively reduce the overall thickness of the filter stack, which is beneficial for achieving a thinner and lighter design of electronic devices.

[0027] In one implementation, the second dielectric layer group is a single refractive dielectric layer, which is one of the first, second, and third refractive dielectric layers. In this implementation, the second dielectric layer group only includes one of the first, second, and third refractive dielectric layers, avoiding a combination of multiple refractive dielectric layers, which helps reduce the processing difficulty and cost of the second dielectric layer group. In another implementation, the second dielectric layer group is equivalent to the reflecting cavity of the Fabry-Perot cavity in the filter. Compared to the parallel flat plates on both sides of the Fabry-Perot cavity, it has little impact on the degree of light interference. Therefore, considering the overall thickness of the filter, in this implementation, it is preferable to set the second dielectric layer group as a single refractive dielectric layer.

[0028] In one implementation, the at least three dielectric layer groups include three dielectric layer groups, the three dielectric layer groups including a first dielectric layer group, a second dielectric layer group and a third dielectric layer group stacked sequentially, the first dielectric layer group being closer to the substrate than the third dielectric layer group, the first dielectric layer group being the same as the third dielectric layer group, the first dielectric layer group being different from the second dielectric layer group, and the first dielectric layer group including the first refractive dielectric layer.

[0029] In this implementation, the first dielectric layer group, the second dielectric layer group, and the third dielectric layer group constitute a Fabry-Perot cavity. The first and third dielectric layer groups are identical, forming a symmetrical structure. This symmetrical structure makes light transmission more stable and accurate, reducing light loss. In this implementation, the first and third dielectric layer groups are equivalent to two parallel plates of the Fabry-Perot cavity, and the second dielectric layer group is the reflecting cavity of the Fabry-Perot cavity.

[0030] In this implementation, the first dielectric layer group is the closest to the substrate among the three dielectric layer groups. That is, after incident light enters from the substrate, it passes through the first dielectric layer group, the second dielectric layer group, and the third dielectric layer group in sequence. The first dielectric layer group serves as the optical input end of the filter stack. A first refractive dielectric layer is provided at the optical input end to reduce the reflectivity of light in the first dielectric layer group and improve the display effect.

[0031] In one implementation, the first dielectric layer group includes at least one first dielectric layer subgroup, which includes at least one of a first refractive dielectric layer, a second refractive dielectric layer, and a third refractive dielectric layer. This solution allows the filter to flexibly incorporate dielectric layers with different refractive indices according to different light output requirements, improving the filter's practicality. In another implementation, the first dielectric layer group includes multiple first dielectric layer subgroups. These multiple subgroups can increase the reflective surface of the incident light, enhance the constructive interference effect, and thus improve the light output performance of the filter.

[0032] In one implementation, the second dielectric layer group includes one of a first refractive dielectric layer, a second refractive dielectric layer, and a third refractive dielectric layer. In this implementation, the second dielectric layer group only includes one of the first, second, and third refractive dielectric layers, and does not involve a combination of multiple refractive dielectric layers, which helps to reduce the processing difficulty and cost of the second dielectric layer group.

[0033] In one implementation, the at least three dielectric layer groups include four dielectric layer groups, the four dielectric layer groups including a fifth dielectric layer group, a first dielectric layer group, a second dielectric layer group and a third dielectric layer group stacked sequentially, the fifth dielectric layer group being located between the substrate and the first dielectric layer group, and the fifth dielectric layer group including the first refractive dielectric layer.

[0034] In this implementation, the fifth dielectric layer group, the first dielectric layer group, the second dielectric layer group, and the third dielectric layer group together constitute a Fabry-Perot cavity. The fifth dielectric layer group and the first dielectric layer group form one plate of the Fabry-Perot cavity in the filter stack, and the third dielectric layer group forms the other plate of the Fabry-Perot cavity in the filter stack. The second dielectric layer group is the reflecting cavity of the Fabry-Perot cavity in the filter stack. This scheme uses a Fabry-Perot cavity-type optical structure in the filter stack, which is beneficial to improving light extraction efficiency. The fifth dielectric layer group is the optical input end of the filter stack. A first refractive dielectric layer with a low refractive index is set in the fifth dielectric layer group to reduce the reflectivity of light in the fifth dielectric layer group and improve the display effect.

[0035] In one implementation, the fifth dielectric layer group includes at least one of a first refractive dielectric layer, a second refractive dielectric layer, and a third refractive dielectric layer, wherein the refractive index of the second refractive dielectric layer is greater than the refractive index of the first refractive dielectric layer, and the refractive index of the third refractive dielectric layer is greater than the refractive index of the second refractive dielectric layer.

[0036] In one implementation, the at least three dielectric layer groups are arranged in a planar manner. Alternatively, the at least three dielectric layer groups are curved, and the center of curvature of each of the at least three dielectric layer groups is disposed away from the substrate.

[0037] In this implementation, at least three dielectric layers are set as a plane, which can reduce the manufacturing difficulty and production cost of the filter stack. Moreover, the thickness of the planar dielectric layer group is thinner, which is conducive to realizing the thinner and lighter design of display components and electronic devices.

[0038] In this implementation, at least three dielectric layer groups are configured as curved surfaces with their curvature centers facing away from the substrate. This indicates that the dielectric layer group closest to the substrate only partially contacts the substrate, ensuring uniform absorption of light incident at different angles by the filter stack. This helps alleviate the problem of low light extraction efficiency for large-angle light. Furthermore, when the filter is applied to an e-ink screen, the incident light is scattered by the microcapsules within the screen. Therefore, the filter stack in this implementation can also function like a lens, focusing the light and further improving light transmittance and color purity.

[0039] In one implementation, the material of the first refractive medium layer is at least one selected from porous silica, porous lithium fluoride, porous polymethyl methacrylate, and porous polydimethylsiloxane. In this implementation, the material of the first refractive medium layer is always a porous material. Air is present in the tiny pores of the porous material. Since the refractive index of air is generally lower than that of solid materials, the overall refractive index of the porous material is relatively low. The low refractive index of the first refractive medium layer can alleviate the problem of low light extraction efficiency at large angles.

[0040] In one embodiment, the material of the second refractive medium layer is at least one selected from silicon dioxide, lithium fluoride, polymethyl methacrylate, and aluminum oxide. Specifically, silicon dioxide has a refractive index greater than or equal to 1.4 and less than or equal to 1.7, lithium fluoride has a refractive index greater than or equal to 1.38 and less than or equal to 1.5, polymethyl methacrylate has a refractive index greater than or equal to 1.4 and less than or equal to 1.8, and aluminum oxide has a refractive index greater than or equal to 1.6 and less than or equal to 1.9. In this implementation, using the above-mentioned materials for the second refractive medium layer helps to reduce the difficulty of setting up filters with high light output.

[0041] In one embodiment, the material of the third refractive medium layer is at least one selected from titanium dioxide, zirconium dioxide, molybdenum trioxide, niobium pentoxide, tellurium dioxide, and silicon nitride. Specifically, titanium dioxide has a refractive index greater than or equal to 2.55 and less than or equal to 2.76; zirconium dioxide has a refractive index greater than or equal to 2.3 and less than or equal to 2.5; molybdenum trioxide has a refractive index greater than or equal to 2.0 and less than or equal to 2.5; niobium pentoxide has a refractive index greater than or equal to 2.0 and less than or equal to 2.5; tellurium dioxide has a refractive index greater than or equal to 2.0 and less than or equal to 2.3; and silicon nitride has a refractive index greater than or equal to 1.8 and less than or equal to 2.2. In this implementation, using the above-mentioned materials for the third refractive medium layer helps to reduce the difficulty of setting up filters with high light output.

[0042] Secondly, this application provides a display component, the display component including a light-emitting functional layer and a filter as described in any implementation of the first aspect, the filter having a plurality of filter stacks located between the light-emitting functional layer and the substrate, the plurality of filter stacks being arranged in an array, the filter stacks being used to transmit target light in incident light and reflect light of other wavelengths, the target light being one of red light, green light or blue light.

[0043] Thirdly, this application provides an electronic device, the electronic device including a housing and a display component as described in the second aspect, fixed to the housing. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments of this application will be described below.

[0045] Figure 1 This is a schematic diagram of the structure of a display component provided in an embodiment of this application;

[0046] Figure 2 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application;

[0047] Figure 3 This is a cross-sectional view of a filter provided in an embodiment of this application;

[0048] Figure 4 This is an embodiment of the present application providing an optical path diagram of light at different incident angles in a filter;

[0049] Figure 5 This is an embodiment of the present application providing an optical path diagram of light at different incident angles in a filter;

[0050] Figure 6 This is a cross-sectional view of a filter provided in an embodiment of this application;

[0051] Figure 7 This is a cross-sectional view of a filter provided in an embodiment of this application;

[0052] Figure 8 This is a cross-sectional view of a filter provided in an embodiment of this application;

[0053] Figure 9 This is a cross-sectional view of a filter provided in an embodiment of this application;

[0054] Figure 10 This is a cross-sectional view of a filter provided in an embodiment of this application;

[0055] Figure 11 This is a cross-sectional view of a filter provided in an embodiment of this application;

[0056] Figure 12 This is a cross-sectional view of a filter provided in an embodiment of this application;

[0057] Figure 13 This is a cross-sectional view of a filter provided in an embodiment of this application;

[0058] Figure 14 This is a cross-sectional view of a filter provided in an embodiment of this application;

[0059] Figure 15 This is a cross-sectional view of a filter provided in an embodiment of this application;

[0060] Figure 16 This is a cross-sectional view of a filter provided in an embodiment of this application. Detailed Implementation

[0061] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0062] In this document, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "multiple" means two or more.

[0063] Furthermore, in this article, directional terms such as "upper" and "lower" are defined relative to the orientation of the structure as shown in the attached drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and can change accordingly depending on the orientation of the structure.

[0064] For ease of understanding, the relevant technical terms involved in the embodiments of this application will be explained and described below.

[0065] Fabry-Perot cavity: Abbreviated as Fabry-Perot cavity, it is an optical application device based on multi-beam interference. It is an optical reflecting cavity composed of two parallel plates (partially transmissive). Light is reflected multiple times in the Fabry-Perot cavity, and light of a specific wavelength will undergo constructive interference in the Fabry-Perot cavity.

[0066] This application provides a filter, including a substrate and a filter stack located on one side of the substrate. The filter stack includes at least three stacked dielectric layer groups, each dielectric layer group consisting of one or more refractive dielectric layers. In at least one dielectric layer group, one refractive dielectric layer includes a first refractive dielectric layer. The refractive index of the first refractive dielectric layer is greater than 1.1 and less than 1.35, or equal to 1.1, or equal to 1.35. The dielectric layer groups in the filter stack form a Fabry-Perot cavity. Incident light of a specific wavelength band undergoes constructive interference in the Fabry-Perot cavity, increasing the transmittance of the incident light in that wavelength band. The first refractive dielectric layer has a very low refractive index, which can compensate for the transmittance and color purity of large-angle incident light to a certain extent. The filter provided by this application can increase the overall transmittance and color purity of incident light, thereby improving the brightness and color gamut of electronic devices and enhancing display performance.

[0067] The filters provided in this application embodiment can be applied to display components, and display components containing the filters of this application can be applied to electronic devices.

[0068] Please see Figure 1 , Figure 1This is a schematic diagram of the structure of a display component 10 provided in an embodiment of this application. In one embodiment, the display component 10 includes a light-emitting functional layer 12 and a filter 11. The filter 11 includes a plurality of filter stacks 100 and a substrate 200. The filter stacks 100 are located between the light-emitting functional layer 12 and the substrate 200 of the filter 11. The plurality of filter stacks 100 are arranged in an array. The filter stacks 100 are used to transmit target light in the incident light and reflect light of other wavelengths. The target light is one of red light, green light and blue light.

[0069] In one embodiment, the light-emitting functional layer 12 can be any one of an electronic ink layer, an OLED (Organic Light-Emitting Diode), and a Micro-OLED. The electronic ink layer is a passive light-emitting device, while the OLED and Micro-OLED are active light-emitting devices. The OLED is a white light-emitting OLED, and the Micro-OLED is a white light-emitting Micro-OLED.

[0070] like Figure 1 As shown, in Figure 1 In the embodiment shown, the display component 10 is an e-ink display component, the light-emitting functional layer 12 is an electronic ink layer, and the electronic ink layer includes a plurality of capsules 101. The plurality of capsules 101 are arranged in a plane parallel to the substrate 200. For example, the plurality of capsules 101 are arranged in an array to form the electronic ink layer, and the arrangement direction of the plurality of capsules 101 is perpendicular to the main light-emitting direction of the display component 10.

[0071] Electrodes 102 are disposed around the periphery of the capsule body 101. Electrodes 102 are transparent and parallel to the substrate 200, located between the electronic ink layer and the substrate 200. Electrodes 102 are used to change the distribution direction of the ink particles 1011 in the capsule body 101. For example, the transparent electrode is made of indium tin oxide. Electrodes 102 are bonded to the electronic ink layer and to the filter 11 using adhesive.

[0072] The capsule 101 contains ink particles 1011. The ink particles 1011 may include a plurality of first color particles and a plurality of second color particles, one of which is a black particle and the other is a white particle. The electrical properties of the first color particles are opposite to those of the second color particles. The white particles are used to reflect incident light, and the black particles are used to absorb incident light.

[0073] When a voltage is applied to electrode 102, an electric field is formed between the cathode and anode of electrode 102. Under the influence of this electric field, electrophoresis occurs, causing some ink particles 1011 to be distributed along electrode 102. Specifically, one of the multiple black particles and multiple white particles will move towards the cathode of electrode 102, and the other will move towards the anode of electrode 102. For example, multiple black particles will move towards the cathode of electrode 102, and white particles will move towards the anode of electrode 102. This results in multiple black particles and multiple white particles being sequentially arranged along the main light-emitting direction of display component 10. The filter stack 100 in the filter 11 of this application is used to transmit the target light in the incident light and reflect light of other wavelengths, such as red, green, and blue light. Figure 1 As shown, the filter stack 100 includes a red filter stack 100a, a green filter stack 100b, and a blue filter stack 100c. The red filter stack 100a is used to pass red light, the green filter stack 100b is used to pass green light, and the blue filter stack 100c is used to pass blue light. A pixel includes the red filter stack 100a, the green filter stack 100b, and the blue filter stack 100c. When a pixel needs to display red light, the white particles in the ink particles 1011 below the red filter stack 100a face upwards and the black particles face downwards, so that the red light transmitted from the red filter stack 100a is reflected by the white particles and then emitted to display red light. The white particles in the ink particles 1011 below the green filter stack 100b and the blue filter stack 100c face downwards and the black particles face upwards. The black particles absorb the light transmitted from the green filter stack 100b and the blue filter stack 100c, so that the pixel as a whole displays red.

[0074] Please see Figure 2 , Figure 2 This is a schematic diagram of the structure of an electronic device 1 provided in one embodiment of the present application. In one embodiment, the electronic device 1 includes a display component 10 and a housing 20, with the display component 10 installed in the housing 20. The electronic device 1 includes, but is not limited to, e-reader tablets, mobile phones, computers, in-vehicle displays, and televisions.

[0075] In the current filter 11, if the filter 11 uses organic dye, the wavelength selectivity of the filter 11 is not strong, and the transmittance and color purity are not high, which affects the performance of the electronic device 1 in terms of brightness and color gamut.

[0076] In this embodiment of the application, by improving the filter 11, the overall transmittance and color purity of the incident light can be increased, thereby improving the display effect.

[0077] The filter 11 provided in the embodiments of this application will be described in detail below.

[0078] Please see Figure 3 , Figure 3 This is a cross-sectional view of a filter 11 provided in one embodiment of the present application. In one embodiment, the filter 11 includes a substrate 200 and a filter stack 100 located on one side of the substrate 200. The filter stack 100 includes at least three stacked dielectric layer groups 110, each dielectric layer group 110 consisting of one or more refractive dielectric layers. In one of the refractive dielectric layers in at least one dielectric layer group 110, a first refractive dielectric layer 111 is included. The refractive index of the first refractive dielectric layer 111 is greater than 1.1 and less than 1.35, or equal to 1.1, or equal to 1.35.

[0079] In this embodiment, the filter stack 100 is located on one side of the substrate 200 along the thickness direction A, wherein a plurality of dielectric layer groups 110 in the filter stack 100 are also stacked along the thickness direction A. Light is incident from the side of the substrate 200 away from the filter stack 100 along the thickness direction A, and then sequentially passes through the plurality of dielectric layer groups 110 in the filter stack 100. At least three dielectric layer groups 110 in the filter stack 100 constitute a Fabry-Perot cavity (hereinafter referred to as Fabry-Perot cavity). The incident light is reflected multiple times in the Fabry-Perot cavity, and the reflected light interferes. Light of a specific wavelength band can undergo constructive interference in the Fabry-Perot cavity, so that the filter 11 can select the wavelength of the incident non-monochromatic light and improve monochromaticity. In particular, when multiple beams of light with a phase difference of 2π after multiple reflections in the Fabry-Perot cavity are superimposed, the intensity of the light emitted from the Fabry-Perot cavity increases, thereby improving the transmittance. In this embodiment, at least one of the refractive medium layers in the dielectric layer group 110 includes a first refractive medium layer 111. The refractive index n1 of the first refractive medium layer 111 satisfies 1.1 < n1 < 1.35, or n1 = 1.1, or n1 = 1.35. The smaller n1 can compensate for the transmittance and color purity of the incident light at a large angle to a certain extent, thereby improving the overall light output effect of the incident light in the filter 11.

[0080] The following explanation uses incident angles of 0° and 45° as examples to illustrate the function of setting the first refractive medium layer 111 in the filter 11 of this application.

[0081] Please see Figure 4 , Figure 4This embodiment of the application provides an optical path diagram of light with different incident angles in filter 11. When the first refractive medium layer 111 is not provided in filter 11, it is assumed that the incident light at 0° satisfies the condition of constructive interference in filter 11, that is, the phase difference is 2π. At this time, the light extraction efficiency of the incident light at 0° reaches 100%. However, the phase difference of the incident light at 45° in filter 11 is 0.75π. At this time, the difference between the phase difference of the incident light at 45° and the incident light at 0° is relatively large. That is to say, the difference angle between the phase difference of the incident light at 45° in filter 11 and the phase difference that can produce constructive interference is relatively large. The difference between 0.75π and 2π is relatively large. It is assumed that the light extraction efficiency of the incident light at 45° is only 80%. Overall, the light extraction efficiency of the incident light in filter 11 is poor.

[0082] Please see Figure 5 , Figure 5 The optical path diagram of light with different incident angles in filter 11 provided in an embodiment of this application is shown below. When a first refractive medium layer 111 is added to filter 11, the optical paths of the incident light at 0° and the incident light at 45° in the first refractive medium layer 111 are denoted as L1 and R1, respectively. Then the phase difference of the incident light at 0° after exiting the first refractive medium layer 111 is n1*L1*2π / λ+2π. Since the phase difference increases by n1*L1*2π / λ, it has a difference from 2π, which makes the light extraction rate of the light with constructive interference after exiting the first refractive medium layer 111 only reach 99%, where λ is the wavelength of the light that satisfies constructive interference.

[0083] Please continue reading. Figure 5 The phase difference of the incident light at 45° exiting the first refractive medium layer 111 is n1*R1*2π / λ+0.75π. Since R1 is the optical path of the incident light at 45° incident at an angle into the first refractive medium layer 111, and L1 is the optical path of the incident light at 0° incident perpendicularly into the first refractive medium layer 111, that is, R1 is greater than L1, which makes n1*R1*2π / λ greater than n1*L1*2π / λ. As a result, the difference between the phase difference n1*R1*2π / λ+0.75π and the phase difference 2π after the incident light at 45° exiting the first refractive medium layer 111 decreases, thereby improving the constructive interference effect and achieving a light extraction efficiency of 90%. Although the difference between the phase difference n1*L1*2π / λ+2π and the phase difference 2π after the incident light at 0° exits from the first refractive medium layer 111 increases, the low refractive index of the first refractive medium layer 111 (i.e., a small value of n1) makes the difference between the phase difference of the incident light at 0° and 2π small, thus reducing the impact on the light extraction efficiency of the incident light at 0°. This results in an increase in the overall light extraction efficiency from the filter 11 compared to when the first refractive medium layer 111 is not present.

[0084] In summary, compared to not having the first refractive medium layer 111, the light extraction efficiency of incident light at 0° is slightly reduced, but the light extraction efficiency of incident light at 45° is significantly improved, thus increasing the overall light extraction efficiency of the filter 11. Furthermore, while a higher refractive index of the first refractive medium layer 111 might improve the light extraction efficiency of incident light at large angles, it could simultaneously reduce the light extraction efficiency of incident light at small angles, thus affecting the overall light extraction efficiency. Moreover, replacing the first refractive medium layer 111 with a high-refractive-index refractive medium layer also presents the problem of poor adjustment precision. Because the high-refractive-index refractive medium layer has a higher refractive index, achieving the same phase difference as the lower-refractive-index first refractive medium layer 111 requires making the high-refractive-index refractive medium layer much thinner, increasing the processing difficulty.

[0085] It should be noted that the above-mentioned light extraction efficiency values ​​only schematically illustrate the effect of the first refractive medium layer 111 on the light extraction efficiency, and do not represent the actual light extraction efficiency of the incident light in the filter 11. Furthermore, 0° and 45° incident light represent small-angle and large-angle incident light, respectively; in other embodiments, the incident angles of small-angle and large-angle incident light can also be other values. It should also be noted that in... Figure 5 In some embodiments, the first refractive medium layer 111 is disposed on the outermost layer away from the substrate 200. In other embodiments, the first refractive medium layer 111 may also be located in the middle layer of the filter 11.

[0086] In this application, by setting a filter 11: First, at least three dielectric layer groups 110 in the filter 11 together form a Fabry-Perot cavity, which can filter light of a specific wavelength band, optimize the color purity of the emitted light, and thereby improve the color gamut of the electronic device 1.

[0087] Second, by setting a first refractive medium layer 111 with a low refractive index in the filter 11, the light extraction efficiency of light incident at large angles can be compensated, and the light extraction efficiency of light incident at small angles has minimal impact. Therefore, the overall light extraction efficiency reduction caused by angle changes can be reduced, thereby improving the brightness of the electronic device 1.

[0088] Third, by setting a first refractive medium layer 111 with a low refractive index in the filter 11, the adjustment accuracy of the filter 11 can be improved and the manufacturing process can be reduced.

[0089] In one embodiment, the substrate 200 may be a transparent substrate, preferably glass. This design helps to reduce the loss of incident light in the substrate 200.

[0090] Please see Figure 6 , Figure 6This is a cross-sectional view of a filter 11 provided in one embodiment of the present application. In one implementation, at least three dielectric layer groups 110 include four dielectric layer groups 110. The four dielectric layer groups 110 include a first dielectric layer group 120, a second dielectric layer group 130, a third dielectric layer group 140, and a fourth dielectric layer group 150 stacked sequentially. The first dielectric layer group 120 is closer to the substrate 200 than the fourth dielectric layer group 150. The fourth dielectric layer group 150 includes a first refractive dielectric layer 111. The first dielectric layer group 120 and the third dielectric layer group 140 are identical, but different from the second dielectric layer group 130.

[0091] In this embodiment, the first dielectric layer group 120, the second dielectric layer group 130, the third dielectric layer group 140 and the fourth dielectric layer group 150 constitute a Fabry-Perot cavity. The first dielectric layer group 120 and the third dielectric layer group 140 are identical and are symmetrical about the second dielectric layer group 130. The symmetrical structure can make the transmission of light more stable and accurate, which is beneficial to reducing light loss.

[0092] In this embodiment, the first dielectric layer group 120 is equivalent to one of the parallel plates of the Fabry-Perot cavity, the third dielectric layer group 140 and the fourth dielectric layer group 150 are equivalent to the other parallel plate of the Fabry-Perot cavity, and the second dielectric layer group 130 is equivalent to the reflecting cavity of the Fabry-Perot cavity. The incident light undergoes multiple reflections in the reflecting cavity, and the light with a phase difference of 2π undergoes constructive interference, thereby comprehensively improving the overall light output efficiency of the filter 11.

[0093] In this embodiment, the fourth dielectric layer group 150 is located on the side of the third dielectric layer group 140 away from the substrate 200 along the thickness direction A. That is, after incident light enters from the substrate 200, it sequentially passes through the first dielectric layer group 120, the second dielectric layer group 130, the third dielectric layer group 140, and the fourth dielectric layer group 150, which includes the first refractive dielectric layer 111. The fourth dielectric layer group 150 is the optical output end of the filter stack 100. The first refractive dielectric layer 111 is provided at the optical output end. Since the refractive index of the first refractive dielectric layer 111 is low, this solution is also beneficial to improve the light extraction efficiency of large-angle light, while reducing the light reflectivity, thereby improving the light transmittance.

[0094] In one embodiment, the fourth dielectric layer group 150 may include only the first refractive dielectric layer 111.

[0095] In one embodiment, the fourth dielectric layer group 150 includes at least one of a first refractive dielectric layer 111 and a second refractive dielectric layer 112 and a third refractive dielectric layer 113, wherein the refractive index of the second refractive dielectric layer 112 is greater than the refractive index of the first refractive dielectric layer 111, and the refractive index of the third refractive dielectric layer 113 is greater than the refractive index of the second refractive dielectric layer 112. By providing multiple refractive dielectric layers in the fourth dielectric layer group 150, the number of reflections in the fourth dielectric layer group 150 is increased, the proportion of constructive interference light is enhanced, and thus the overall light output effect of the filter 11 is improved.

[0096] Please see Figure 7 , Figure 7 This is a cross-sectional view of a filter 11 provided in an embodiment of this application. In one embodiment, the first dielectric layer group 120 includes at least two first dielectric layer subgroups 121. Each first dielectric layer subgroup 121 includes at least one of a first refractive dielectric layer 111, a second refractive dielectric layer 112, and a third refractive dielectric layer 113, wherein the refractive index of the second refractive dielectric layer 112 is greater than the refractive index of the first refractive dielectric layer 111, and the refractive index of the third refractive dielectric layer 113 is greater than the refractive index of the second refractive dielectric layer 112.

[0097] In this embodiment, the first dielectric layer group 120 serves as the optical input end of the filter stack 100. A first refractive dielectric layer 111, a second refractive dielectric layer 112, and a third refractive dielectric layer 113 with different refractive indices are disposed at the optical input end. This allows the filter 11 to be flexibly configured with dielectric layers of different refractive indices according to different light output requirements, improving the practicality of the filter 11. The number of the first dielectric layer subgroup 121 can be determined as needed. Figure 7 In the filter 11 shown, the first dielectric layer group 120 includes a first dielectric layer subgroup 121, which includes a first refractive dielectric layer 111, a second refractive dielectric layer 112, and a third refractive dielectric layer 113. In one embodiment, when the first dielectric layer group 120 includes two or more first dielectric layer subgroups 121, each first dielectric layer subgroup 121 in the first dielectric layer group 120 has the same composition, and each dielectric layer subgroup is stacked sequentially to form the first dielectric layer group 120.

[0098] In this embodiment, the first dielectric layer group 120 and the third dielectric layer group 140 form a symmetrical structure, and the first dielectric layer group 120 and the third dielectric layer group 140 have the same composition. When the first dielectric layer group 120 includes multiple first dielectric layer subgroups 121 and the third dielectric layer group 140 includes multiple third dielectric layer subgroups, the number of reflections of incident light in the Fabry-Perot cavity is increased, the proportion of constructive interference light is increased, and thus the overall light output effect of the filter 11 is improved. It should be noted that when the first dielectric layer group 120 includes three or more first dielectric layer subgroups 121, any three refractive dielectric layers of the first dielectric layer group 120 may form a Fabry-Perot cavity that causes constructive interference for some light. However, the Fabry-Perot cavity in the first dielectric layer group 120 is smaller than the Fabry-Perot cavity of the filter stack 100 as a whole. In this embodiment, the light output effect of the filter 11 should be described with reference to the Fabry-Perot cavity of the filter stack 100 as a whole.

[0099] For example, in one implementation, when the first dielectric layer group 120 includes two first dielectric layer subgroups 121, and each first dielectric layer subgroup 121 includes a second refractive medium layer 112 and a third refractive medium layer 113, the arrangement order of the refractive medium layers in the first dielectric layer group 120 is second refractive medium layer 112, third refractive medium layer 113, second refractive medium layer 112, third refractive medium layer 113. In another implementation, the first dielectric layer group 120 may include only one first dielectric layer subgroup 121, and when the first dielectric layer subgroup 121 includes a second refractive medium layer 112 and a third refractive medium layer 113, the arrangement order of the refractive medium layers in the first dielectric layer group 120 is second refractive medium layer 112, third refractive medium layer 113.

[0100] In one embodiment, the refractive index n2 of the second refractive medium layer 112 satisfies 1.38 ≤ n2 ≤ 1.9, and the refractive index n3 of the third refractive medium layer 113 satisfies 1.8 ≤ n3 ≤ 2.76. It should be noted that although there is no clear boundary between the values ​​of n2 and n3, and they partially overlap, in specific application scenarios, n3 > n2 must be satisfied. In this embodiment, the refractive indices of the second refractive medium layer 112 and the third refractive medium layer 113 satisfy the above range, which helps to reduce the difficulty of setting up a high-output filter 11.

[0101] Please see Figure 8 , Figure 8 This is a cross-sectional view of a filter 11 provided in an embodiment of this application. In one embodiment, the first dielectric layer subgroup 121 includes a second refractive dielectric layer 112 and two third refractive dielectric layers 113. The two third refractive dielectric layers 113 are respectively located on both sides of the second refractive dielectric layer 112, and the sum of the thicknesses of the two third refractive dielectric layers 113 is equal to the thickness of the second refractive dielectric layer 112.

[0102] In this embodiment, in the first dielectric layer subgroup 121, the thickness D1 of one third refractive dielectric layer 113 is half the thickness D2 of the second refractive dielectric layer 112. Since the filter stack 100 has a large number of refractive dielectric layers, adjusting the thickness of the third refractive dielectric layer 113 to half the thickness of the second refractive dielectric layer 112 can effectively reduce the overall thickness of the filter stack 100, which is beneficial to achieving a thinner and lighter design for the electronic device 1. Furthermore, compared to using one third refractive dielectric layer 113 with the same thickness as the second refractive dielectric layer 112, setting two third refractive dielectric layers 113 with a thickness half that of the second refractive dielectric layer 112 increases the number of reflection interfaces and the number of reflections while maintaining the same thickness. This increases the amount of light undergoing constructive interference and improves the light extraction efficiency of large-angle light in the filter 11.

[0103] In this embodiment, the thickness of each dielectric layer group 110 in the filter stack 100 is equal, which helps to reduce design difficulty. In some embodiments, when the target light to be transmitted by the filter stack 100 is different, the thickness of the respective dielectric layer group 110 corresponding to the different filter stacks 100 is set to different values ​​as needed to ensure the transmission effect of the target light.

[0104] Please see Figure 9 , Figure 9 This is a cross-sectional view of a filter 11 provided in one embodiment of this application. In other embodiments, the thicknesses of the first dielectric layer group 120 and the third dielectric layer group 140 in the filter stack 100 are not equal. This embodiment is applicable to the case where the refractive indices of the first dielectric layer group 120 and the third dielectric layer group 140 are not equal. By adjusting the thicknesses of the first dielectric layer group 120 and the third dielectric layer group 140, the first dielectric layer group 120 and the third dielectric layer group 140 can be made to have the same light extraction efficiency.

[0105] Please continue reading. Figure 8 In one embodiment, the thickness D3 of a first refractive medium layer 111 in the fourth dielectric layer group 150 is equal to the thickness D1 of a third refractive medium layer 113 in the first dielectric layer subgroup 121. In this embodiment, since the filter stack 100 has a large number of refractive medium layers, adjusting the thickness of the first refractive medium layer 111 and the third refractive medium layer 113 to half that of the second refractive medium layer 112 can effectively reduce the overall thickness of the filter stack 100, which is beneficial for achieving a thinner and lighter design of the electronic device 1.

[0106] Please see Figure 10 , Figure 10This is a cross-sectional view of a filter 11 provided in one embodiment of this application. In one embodiment, the second dielectric layer group 130 is a refractive dielectric layer, which is one of a first refractive dielectric layer 111, a second refractive dielectric layer 112, and a third refractive dielectric layer 113. In this embodiment, the second dielectric layer group 130 only includes one of the first refractive dielectric layer 111, the second refractive dielectric layer 112, and the third refractive dielectric layer 113, and does not involve a combination of multiple refractive dielectric layers, which is beneficial to reducing the processing difficulty and cost of the second dielectric layer group 130. In one embodiment, the second dielectric layer group 130 is equivalent to the reflecting cavity of the Fabry-Perot cavity in the filter 11. Compared with the parallel flat plate layers on both sides of the Fabry-Perot cavity, it has little impact on the degree of light interference. Therefore, in this embodiment, considering the overall thickness of the filter 11, it is preferable that the second dielectric layer group 130 is provided as a single refractive dielectric layer.

[0107] Please see Figure 11 , Figure 11 This is a cross-sectional view of a filter 11 provided in an embodiment of this application. Figure 11 The diagram illustrates the stacking distribution of the filter stack 100, which includes a first dielectric layer group 120, a second dielectric layer group 130, a third dielectric layer group 140, and a fourth dielectric layer group 150. The first dielectric layer group 120 is defined as "(112+113)*n", where "(112+113)*n" indicates that the first dielectric layer group 120 contains n dielectric layer subgroups, each containing a second refractive dielectric layer 112 and a third refractive dielectric layer 113, where n is a positive integer. The third dielectric layer group 140 is the same as the first dielectric layer group 120. The second dielectric layer group 130 is defined as "111 / 112 / 113", where "111 / 112 / 113" indicates that the second dielectric layer group 130 can be any one of the first refractive dielectric layer 111, the second refractive dielectric layer 112, and the third refractive dielectric layer 113.

[0108] In one embodiment, the number n of the dielectric layer subgroups in the third dielectric layer group 140 and the first dielectric layer group 120 is an integer greater than or equal to 1 and less than or equal to 20. In another embodiment, the number n of the dielectric layer subgroups in the third dielectric layer group 140 and the first dielectric layer group 120 is an integer greater than or equal to 1 and less than or equal to 10.

[0109] It should be noted that, Figure 11 The distribution of the refractive medium layer in each of the four dielectric layer groups 110 in the filter stack 100 is not exhaustively listed. The possible implementation methods of the refractive medium layer in the filter in this embodiment described above are applicable to the scheme described in this embodiment.

[0110] Please see Figure 12 , Figure 12This is a cross-sectional view of a filter 11 provided in an embodiment of this application. In one embodiment, at least three dielectric layer groups 110 include three dielectric layer groups 110. The three dielectric layer groups 110 include a first dielectric layer group 120, a second dielectric layer group 130 and a third dielectric layer group 140 stacked sequentially. The first dielectric layer group 120 is closer to the substrate 200 than the third dielectric layer group 140. The first dielectric layer group 120 and the third dielectric layer group 140 are the same. The first dielectric layer group 120 is different from the second dielectric layer group 130. The first dielectric layer group 120 includes a first refractive dielectric layer 111.

[0111] In this embodiment, the first dielectric layer group 120, the second dielectric layer group 130, and the third dielectric layer group 140 constitute a Fabry-Perot cavity. The first dielectric layer group 120 and the third dielectric layer group 140 are identical, forming a symmetrical structure. This symmetrical structure makes light transmission more stable and accurate, reducing light loss. In this embodiment, the first dielectric layer group 120 and the third dielectric layer group 140 are equivalent to two parallel plates of the Fabry-Perot cavity, and the second dielectric layer group 130 is the reflecting cavity of the Fabry-Perot cavity.

[0112] In this embodiment, the first dielectric layer group 120 is the closest to the substrate 200 among the three dielectric layer groups 110. That is, after incident light enters from the substrate 200, it passes through the first dielectric layer group 120, the second dielectric layer group 130, and the third dielectric layer group 140 in sequence. The first dielectric layer group 120 is the optical input end of the filter stack 100. A first refractive dielectric layer 111 is provided at the optical input end to reduce the reflectivity of light in the first dielectric layer group 120 and improve the display effect.

[0113] In one embodiment, the first dielectric layer group 120 includes at least one first dielectric layer subgroup 121, which includes at least one of a first refractive dielectric layer 111, a second refractive dielectric layer 112, and a third refractive dielectric layer 113. This design allows the filter 11 to be flexibly configured with dielectric layers of different refractive indices according to different light emission requirements, thereby improving the practicality of the filter 11. In another embodiment, the first dielectric layer group 120 includes multiple first dielectric layer subgroups 121. Multiple first dielectric layer subgroups 121 can increase the reflective surface of the incident light, improve the constructive interference effect, and thus improve the light emission effect of the filter 11.

[0114] In one embodiment, the second dielectric layer group 130 includes one of a first refractive dielectric layer 111, a second refractive dielectric layer 112, and a third refractive dielectric layer 113. In this embodiment, the second dielectric layer group 130 only includes one of the first refractive dielectric layer 111, the second refractive dielectric layer 112, and the third refractive dielectric layer 113, and does not involve a combination of multiple refractive dielectric layers, which helps to reduce the processing difficulty and cost of the second dielectric layer group 130.

[0115] Please see Figure 13 , Figure 13 This is a cross-sectional view of a filter 11 provided in an embodiment of this application. Figure 11 The diagram schematically illustrates the stacked distribution of the filter stack 100, comprising a first dielectric layer group 120, a second dielectric layer group 130, and a third dielectric layer group 140. The first dielectric layer group 120 is defined as "(111+113)*n", where "(111+113)*n" indicates that the first dielectric layer group comprises n first dielectric layer subgroups, each of which includes a first refractive dielectric layer 111 and a third refractive dielectric layer 113. In one embodiment, the number n of the third dielectric layer group 140 and the number of dielectric layer subgroups in the first dielectric layer group 120 is an integer greater than or equal to 1 and less than or equal to 20. In another embodiment, the number n of the third dielectric layer group 140 and the number of dielectric layer subgroups in the first dielectric layer group 120 is an integer greater than or equal to 1 and less than or equal to 10.

[0116] It should be noted that, Figure 13 The distribution of the refractive medium layer in each of the three dielectric layer groups 110 in the filter stack 100 is not exhaustive. The possible implementation methods of the refractive medium layer in the filter in this embodiment described above are applicable to the scheme described in this embodiment.

[0117] Please see Figure 14 , Figure 14 This is a cross-sectional view of a filter 11 provided in an embodiment of this application. In one embodiment, at least three dielectric layer groups 110 include four dielectric layer groups 110. The four dielectric layer groups 110 include a fifth dielectric layer group 160, a first dielectric layer group 120, a second dielectric layer group 130 and a third dielectric layer group 140 stacked sequentially. The fifth dielectric layer group 160 is located between the substrate 200 and the first dielectric layer group 120. The fifth dielectric layer group 160 includes a first refractive dielectric layer 111.

[0118] In this implementation, the fifth dielectric layer group 160, the first dielectric layer group 120, the second dielectric layer group 130, and the third dielectric layer group 140 constitute a Fabry-Perot cavity. The fifth dielectric layer group 160 and the first dielectric layer group 120 form one plate of the Fabry-Perot cavity in the filter stack 100, and the third dielectric layer group 140 forms the other plate of the Fabry-Perot cavity in the filter stack 100. The second dielectric layer group 130 is the reflecting cavity of the Fabry-Perot cavity in the filter stack 100. This scheme sets a Fabry-Perot cavity optical structure in the filter stack 100, which is beneficial to improving the light extraction efficiency. The fifth dielectric layer group 160 is the optical input end of the filter stack 100. A first refractive dielectric layer 111 with a low refractive index is set in the fifth dielectric layer group 160 to reduce the reflectivity of light in the fifth dielectric layer group 160 and improve the display effect.

[0119] Please continue reading. Figure 14 In one embodiment, the fifth dielectric layer group 160 may include at least one of the first refractive dielectric layer 111, the second refractive dielectric layer 112, and the third refractive dielectric layer 113. In this embodiment, the fifth dielectric layer group 160 and the first dielectric layer group 120 constitute one plate in the Fabry-Perot cavity of the filter stack 100, the third dielectric layer group 140 constitutes the other plate in the Fabry-Perot cavity of the filter stack 100, and the second dielectric layer group 130 is the reflecting cavity of the Fabry-Perot cavity of the filter stack 100.

[0120] In another embodiment, the fifth dielectric layer group 160 includes a plurality of fifth dielectric layer subgroups 161, each fifth dielectric layer subgroup 161 including at least one of a first refractive dielectric layer 111, a second refractive dielectric layer 112 and a third refractive dielectric layer 113.

[0121] Please continue reading. Figure 14 In one embodiment, at least three dielectric layer groups 110 are arranged in a planar manner. In this embodiment, by arranging at least three dielectric layer groups 110 in a planar manner, compared with arranging them in a spherical manner, this solution can reduce the manufacturing difficulty and production cost of the filter stack 100, and the planar dielectric layer group 110 is thinner, which is beneficial to realizing the thinner and lighter design of the display component 10 and the electronic device 1.

[0122] Please see Figure 15 , Figure 15 This is a cross-sectional view of a filter 11 provided in an embodiment of this application. In one embodiment, at least three dielectric layer groups 110 are curved, and the curvature center of each of the at least three dielectric layer groups 110 is disposed away from the substrate 200.

[0123] In this embodiment, at least three dielectric layer groups 110 are configured as curved surfaces, with the center of curvature facing away from the substrate 200. This indicates that the dielectric layer group 110 closest to the substrate 200 only partially contacts the substrate 200, making the absorption of light incident at different angles uniform by the filter stack 100, which helps to alleviate the problem of low light extraction efficiency of large-angle light.

[0124] Please see Figure 15Taking a 45° incident light incident on the substrate 200 as an example, on the incident surface of the substrate 200, the incident angle of the 45° incident light is 45°. When the incident light is incident on the filter stack 100, since the dielectric layer group 110 is curved, when the 45° incident light is incident on the surface of the dielectric layer group 110, the normal of the 45° incident light on the surface of the dielectric layer group 110 deviates from the normal of the substrate 200, so that the actual incident angle α of the 45° incident light on the surface of the dielectric layer group 110 becomes smaller. This is equivalent to changing the large-angle incident light into a small-angle incident light that is incident on the dielectric layer group 110 of the filter stack 100, thereby improving the light extraction rate and improving the display effect.

[0125] Furthermore, when the filter 11 is applied to an e-ink screen, the incident light will be scattered by the microcapsules in the e-ink screen. Therefore, the filter stack 100 in this embodiment can also act as a lens, which is beneficial to focus the light and further improve the light transmittance and color purity.

[0126] In one embodiment, the material of the first refractive medium layer 111 is at least one of porous silica, porous lithium fluoride, porous polymethyl methacrylate, and porous polydimethylsiloxane.

[0127] In this embodiment, the material of the first refractive medium layer 111 is a porous material. Air is present in the tiny pores of the porous material. Since the refractive index of air is usually less than that of solid materials, the overall refractive index of the porous material is relatively small.

[0128] In one embodiment, the material of the second refractive medium layer 112 is at least one selected from silicon dioxide, lithium fluoride, polymethyl methacrylate, and aluminum oxide. Specifically, silicon dioxide has a refractive index greater than or equal to 1.4 and less than or equal to 1.7, lithium fluoride has a refractive index greater than or equal to 1.38 and less than or equal to 1.5, polymethyl methacrylate has a refractive index greater than or equal to 1.4 and less than or equal to 1.8, and aluminum oxide has a refractive index greater than or equal to 1.6 and less than or equal to 1.9.

[0129] In one embodiment, the material of the third refractive medium layer 113 is at least one selected from titanium dioxide, zirconium dioxide, molybdenum trioxide, niobium pentoxide, tellurium dioxide, and silicon nitride. Specifically, titanium dioxide has a refractive index greater than or equal to 2.55 and less than or equal to 2.76; zirconium dioxide has a refractive index greater than or equal to 2.3 and less than or equal to 2.5; molybdenum trioxide has a refractive index greater than or equal to 2.0 and less than or equal to 2.5; niobium pentoxide has a refractive index greater than or equal to 2.0 and less than or equal to 2.5; tellurium dioxide has a refractive index greater than or equal to 2.0 and less than or equal to 2.3; and silicon nitride has a refractive index greater than or equal to 1.8 and less than or equal to 2.2.

[0130] In one embodiment, the thicknesses of the first refractive medium layer 111, the second refractive medium layer 112, and the third refractive medium layer 113 may be the same or different in the filter stack 100 of different colors, and can be set according to the refractive index and the number of layers.

[0131] In one embodiment, when the material of the first refractive medium layer 111 is porous silica or porous polymethyl methacrylate, in the blue light filter stack, the thickness of the first refractive medium layer 111 is greater than or equal to 45 nanometers and less than or equal to 135 nanometers. In the green light filter stack, the thickness of the first refractive medium layer 111 is greater than or equal to 50 nanometers and less than or equal to 150 nanometers. In the red light filter stack, the thickness of the first refractive medium layer 111 is greater than or equal to 60 nanometers and less than or equal to 180 nanometers.

[0132] In one embodiment, when the material of the second refractive medium layer 112 is silicon dioxide or polymethyl methacrylate, in the blue light filter stack, the thickness of the second refractive medium layer 112 is greater than or equal to 30 nanometers and less than or equal to 100 nanometers. In the green light filter stack, the thickness of the second refractive medium layer 112 is greater than or equal to 40 nanometers and less than or equal to 115 nanometers. In the red light filter stack, the thickness of the second refractive medium layer 112 is greater than or equal to 45 nanometers and less than or equal to 130 nanometers.

[0133] In one embodiment, when the material of the second refractive medium layer 112 is lithium fluoride, in the blue light filter stack, the thickness of the second refractive medium layer 112 is greater than or equal to 40 nanometers and less than or equal to 110 nanometers. In the green light filter stack, the thickness of the second refractive medium layer 112 is greater than or equal to 45 nanometers and less than or equal to 130 nanometers. In the red light filter stack, the thickness of the second refractive medium layer 112 is greater than or equal to 50 nanometers and less than or equal to 150 nanometers.

[0134] In one embodiment, when the material of the third refractive medium layer 113 is titanium dioxide, in the blue light filter stack, the thickness of the third refractive medium layer 113 is greater than or equal to 15 nanometers and less than or equal to 60 nanometers. In the green light filter stack, the thickness of the third refractive medium layer 113 is greater than or equal to 20 nanometers and less than or equal to 75 nanometers. In the red light filter stack, the thickness of the third refractive medium layer 113 is greater than or equal to 25 nanometers and less than or equal to 100 nanometers.

[0135] In one embodiment, when the material of the third refractive medium layer 113 is zirconium dioxide, molybdenum trioxide, or niobium pentoxide, in the blue light filter stack, the thickness of the third refractive medium layer 113 is greater than or equal to 15 nanometers and less than or equal to 75 nanometers. In the green light filter stack, the thickness of the third refractive medium layer 113 is greater than or equal to 20 nanometers and less than or equal to 90 nanometers. In the red light filter stack, the thickness of the third refractive medium layer 113 is greater than or equal to 25 nanometers and less than or equal to 120 nanometers.

[0136] The following describes the preparation process of the filter 11 provided in an embodiment of this application, including steps S100, S200, S300, S400, S500, and S600, in conjunction with... Figure 16 , Figure 16 This is a cross-sectional view of a filter 11 provided in an embodiment of this application.

[0137] In step S100, the substrate 200 is first cleaned, and then a filter stack 100 for transmitting red light is deposited onto the substrate 200. The method for forming the red light filter stack 100 includes magnetron sputtering, evaporation, and atomic layer deposition. In this embodiment, the refractive medium layer in the filter stack 100 includes an inorganic material, and the inorganic material deposition is preferably performed using methods such as magnetron sputtering, evaporation, or atomic layer deposition. In one embodiment, when the refractive medium layer is made of an organic material, it can be formed using inkjet printing.

[0138] In step S200, photoresist is coated on the filter stack 100, and then pre-baking, exposure, development (using KOH or Na2CO3), and post-baking are performed to complete the patterning of the photoresist.

[0139] In step S300, the filter stack material in the non-patterned area is etched away using ICP-plasma dry etching (using inert gases such as CF4 / SF6), and then the photoresist is removed using acetone to obtain the red light pattern (R).

[0140] In step S400, the photomask of the lithography machine is moved to the position corresponding to the green light pattern and the blue light pattern, and the above operation steps S100 to S300 are repeated (wherein the filter stack in S100 is replaced by a filter stack for transmitting green light and a filter stack for transmitting blue light, respectively), so as to obtain the green light pattern (R) and the blue light pattern (B), and finally the RGB pixel arrangement can be realized.

[0141] In step S500, the planarization layer 103 material is deposited onto the filter stack 100 by scraping to achieve planarization. The planarization layer 103 can be formed by UV curing or thermal curing. For example, the planarization layer 103 material can be a UV-curable adhesive or a thermally curable adhesive.

[0142] In step S600, the electrode 102 material is finally sputtered onto the planarization layer 103 material to form a layer as shown in the figure. Figure 16 The layered distribution is shown. Electrode 102 is made of indium tin oxide.

[0143] To better illustrate the technical solution of this application, several different examples are provided below. To simplify the description of the filter stack distribution, the distribution of the first refractive medium layer, the second refractive medium layer, and the third refractive medium layer is denoted as UL, L, and H, and the substrate is denoted as Substrate.

[0144] In Example 1, the distribution of the filter stack is UL / LH / UL / LHUL / Substrate, where the left and right sides of the " / " are different dielectric layer groups. The total number of all refractive dielectric layers is 7, and each layer has the same thickness. The pixel arrangement is RGBW. For specific effects, please refer to Example 1 in Table 1.

[0145] In Example 2, the distribution of the filter stack is the same as in the example above. The difference is that the pixel arrangement in this embodiment is RGB. For the specific effect, please refer to Example 2 in Table 1.

[0146] In Example 3, the distribution of the filter stack is UL / (LH)*2 / UL / (LHUL)*3 / Substrate, where “ / (LH)*2 / ” indicates that this dielectric layer group includes two dielectric layer subgroups. Each dielectric layer subgroup includes a third refractive dielectric layer H and a second refractive dielectric layer L. The total number of all refractive dielectric layers is 15, and the pixel arrangement is RGBW. For the specific effect, please refer to Example 3 in Table 1.

[0147] In Example 4, the distribution of the filter stack is the same as in the example above. The difference is that the pixel arrangement in this example is RGB. For the specific effect, please refer to Example 4 in Table 1.

[0148] In Example 5, the distribution of the filter stack is (ULH)*6 / L / (ULH)*6 / Substrate, the total number of all refractive medium layers is 25, and the pixel arrangement is RGBW. For the specific effect, please refer to Example 5 in Table 1.

[0149] In Example 6, the distribution of the filter stack is the same as in the example above. The difference is that the pixel arrangement in this example is RGB. For the specific effect, please refer to Example 6 in Table 1.

[0150] In Example 7, the distribution of the filter stack is (ULH)*3 / H / (ULH)*3 / Substrate, the total number of all refractive medium layers is 13, and the pixel arrangement is RGBW. For the specific effect, please refer to Example 7 in Table 1.

[0151] In Example 8, the distribution of the filter stack is the same as in the example above. The difference is that the pixel arrangement in this example is RGB. For the specific effect, please refer to Example 8 in Table 1.

[0152] In Example 9, the filter is made by mixing organic dye with photoresist, which is a commonly used filter in the prior art. It does not involve the superposition of multiple dielectric layers with different refractive indices. The pixel arrangement in this example is RGBW. For the specific effect, please refer to Example 9 in Table 1.

[0153] In Example 10, the difference from the examples above is that the pixel arrangement in this example is RGB.

[0154] Please refer to Table 1 below for details. Table 1 shows the structural parameters of the filters in Examples 1 to 10, as well as performance parameters such as reflectivity and color gamut. Examples 1 to 8 are eight embodiments provided in this application, and Examples 9 to 10 are prior art solutions used for comparison. In Table 1, the pixel arrangement "RGB" represents red, green, and blue; the pixel arrangement "RGBW" represents red, green, blue, and white; "Total number of refractive medium layers" represents the total number of refractive medium layers in the filter stack; and "R / G / B filter stack thickness" represents the thickness of the red light filter stack, the thickness of the green light filter stack, and the thickness of the blue light filter stack, respectively. The reflectivity and color gamut in Table 1 are percentage increases compared to when no filter is used.

[0155] Table 1

[0156]

[0157] As can be seen from Table 1 above, in Examples 1 to 8, except for Example 2, the reflectivity of the filters in the other examples is higher than that of the filters in Examples 9 and 10. The color gamut of the filters in Examples 1 to 8 is higher than that of the filters in Examples 9 and 10. For some ultra-narrow spectra (Examples 7 and 8 in Table 1), using the filters in the embodiments of this application can increase the reflectivity to 51% and the color gamut to 43%. This shows that using the filters provided in the embodiments of this application is beneficial to improving the light extraction efficiency of incident light in the filter. When the filters are applied to electronic devices, the display effect of the electronic devices in terms of brightness and color gamut can be improved.

[0158] The filters, display components, and electronic devices provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and embodiments of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in specific embodiments and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An optical filter, characterized by, The filter stack includes a substrate and a filter layer located on one side of the substrate. The filter stack includes at least three stacked dielectric layer groups, which constitute a Fabry-Perot cavity. Each dielectric layer group consists of one or more refractive dielectric layers. At least one of the refractive dielectric layers in at least one dielectric layer group includes a first refractive dielectric layer, the refractive index of which is greater than 1.1 and less than 1.35, or equal to 1.1, or equal to 1.

35. The at least three dielectric layer groups include four dielectric layer groups, each comprising a first dielectric layer group, a second dielectric layer group, a third dielectric layer group, and a fourth dielectric layer group stacked sequentially. The first dielectric layer group is closer to the substrate than the fourth dielectric layer group, and the fourth dielectric layer group includes the first refractive dielectric layer; or The at least three dielectric layer groups include three dielectric layer groups, each comprising a first dielectric layer group, a second dielectric layer group, and a third dielectric layer group stacked sequentially. The first dielectric layer group is closer to the substrate than the third dielectric layer group. The first dielectric layer group and the third dielectric layer group are identical, while the first dielectric layer group differs from the second dielectric layer group. The first dielectric layer group includes the first refractive dielectric layer; or The at least three dielectric layer groups include four dielectric layer groups, the four dielectric layer groups including a fifth dielectric layer group, a first dielectric layer group, a second dielectric layer group and a third dielectric layer group stacked sequentially, the fifth dielectric layer group being located between the substrate and the first dielectric layer group, and the fifth dielectric layer group including the first refractive dielectric layer.

2. The filter according to claim 1, characterized in that The first dielectric layer group is the same as the third dielectric layer group, and the first dielectric layer group is different from the second dielectric layer group.

3. The filter of claim 1, wherein, The first dielectric layer group includes at least two first dielectric layer subgroups, each of which includes at least one of a first refractive medium layer, a second refractive medium layer, and a third refractive medium layer, wherein the refractive index of the second refractive medium layer is greater than the refractive index of the first refractive medium layer, and the refractive index of the third refractive medium layer is greater than the refractive index of the second refractive medium layer.

4. The filter according to claim 3, characterized in that The first dielectric layer subgroup includes one second refractive dielectric layer and two third refractive dielectric layers, with the two third refractive dielectric layers located on both sides of the second refractive dielectric layer, and the sum of the thicknesses of the two third refractive dielectric layers equal to the thickness of one second refractive dielectric layer.

5. The filter of claim 3, wherein, The second dielectric layer group is a refractive dielectric layer, which is one of the first refractive dielectric layer, the second refractive dielectric layer and the third refractive dielectric layer.

6. The filter according to any one of claims 1 to 5, characterized in that The at least three dielectric layers are arranged in a planar configuration; or The at least three dielectric layer groups are curved, and the center of curvature of each of the at least three dielectric layer groups is disposed away from the substrate.

7. The filter according to any one of claims 1-5, characterized in that, The material of the first refractive medium layer is at least one of porous silica, porous lithium fluoride, porous polymethyl methacrylate, and porous polydimethylsiloxane.

8. A display component, characterized in that, The display component includes a light-emitting functional layer and a filter as described in any one of claims 1-7. The filter has a plurality of filter stacks located between the light-emitting functional layer and the substrate. The plurality of filter stacks are arranged in an array. The filter stacks are used to transmit target light in the incident light and reflect light of other wavelengths. The target light is one of red light, green light, or blue light.

9. An electronic device, characterized in that, The electronic device includes a housing and a display component as described in claim 8, which is fixed to the housing.

Images