CN113031355A

CN113031355A - Reflection-type array substrate, preparation method thereof and display device

Info

Publication number: CN113031355A
Application number: CN202110221019.9A
Authority: CN
Inventors: 郭康; 谷新
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2021-02-26
Filing date: 2021-02-26
Publication date: 2021-06-25

Abstract

Embodiments of the present invention provide a reflective array substrate, a preparation method thereof, and a display device. The reflective array substrate includes a substrate substrate, an array structure layer and a structure color layer that are stacked in sequence, the structure color layer includes a structure layer, the structure layer includes a plurality of structure arrays, each structure array includes a plurality of sub-arrays, each Each sub-array corresponds to one sub-pixel, and each sub-array is composed of a plurality of nano-pillars with the same height, which are used to reflect light of one color. Compared with the scheme using the color filter layer, the display brightness can be improved.

Description

Reflection-type array substrate, preparation method thereof and display device

Technical Field

The embodiment of the disclosure relates to the technical field of display, in particular to a reflection-type array substrate, a preparation method thereof and a display device.

Background

Liquid Crystal Displays (LCDs) can be classified into transmissive type, reflective type and transflective type according to the manner of lighting. Among them, the reflective LCD displays by using reflection of ambient light (e.g., sunlight), and has advantages of high contrast, low power consumption, thin body, light weight, and the like, compared to the transmissive LCD having a backlight, because the reflective LCD does not have a backlight, and it is advantageous for visual protection by using natural light reflection display. Accordingly, the reflective type LCD is increasingly applied to portable electronic terminals such as cellular phones, notebook computers, digital cameras, personal digital assistants, and the like.

A conventional reflective LCD has a main structure including a Thin Film Transistor (TFT) substrate and a Color Filter (CF) substrate, and Liquid Crystal (LC) filled between the TFT substrate and the Color Filter substrate. When natural light is used as a light source, the CF layer is present, and the reflectance is low, which causes a problem of low luminance, and when a front light source is used as a light source, power consumption is large.

Disclosure of Invention

The technical problem to be solved by the embodiments of the present invention is to provide a reflective array substrate, a method for manufacturing the same, and a display device, so as to solve the technical problem of low brightness of the existing structure.

In order to solve the above technical problem, an embodiment of the present invention provides a reflection-type array substrate, including a substrate, an array structure layer, and a structure color layer stacked in sequence, where the structure color layer includes a structure layer, the structure layer includes a plurality of structure arrays, each structure array includes a plurality of sub-arrays, each sub-array corresponds to one sub-pixel, and each sub-array is composed of a plurality of nano-pillars with the same height, and is used to reflect light of one color.

Optionally, the structural layer is a super-surface structure.

Optionally, the period of the nano-pillars in the sub-array for reflecting red light is 160 to 300nm, the height of the nano-pillars is 80 to 150nm, and the structural width of the nano-pillars is 80 to 150 nm; the period of the nano-pillars in the sub-array for reflecting the green light is 240-450 nm, the height of the nano-pillars is 80-150 nm, and the structural width of the nano-pillars is 80-150 nm; the period of the nano-pillars in the subarray for reflecting blue light is 320-600 nm, the height of the nano-pillars is 80-150 nm, and the structural width of the nano-pillars is 80-150 nm.

Optionally, the period of the nano-pillars in the sub-array for reflecting red light is 150 to 200nm, the height of the nano-pillars is 80 to 150nm, and the structural width of the nano-pillars is 100 to 130 nm; the period of the nano-pillars in the sub-array for reflecting the green light is 150 to 200nm, the height of the nano-pillars is 80 to 150nm, and the structural width of the nano-pillars is 70 to 100 nm; the period of the nano-pillars in the subarray for reflecting blue light is 150 to 200nm, the height of the nano-pillars is 80 to 150nm, and the structural width of the nano-pillars is 40 to 70 nm.

Optionally, the structural color layer further comprises a protective layer on the structural layer.

Optionally, the array structure layer includes a gate electrode, a gate insulating layer, an active layer, a source drain electrode, a passivation layer, a pixel electrode, and a planarization layer, which are sequentially disposed on the substrate.

Optionally, the material of the super-surface structure comprises aluminum, silver, or an aluminum neodymium alloy.

Embodiments of the present invention also provide a display device, including a first substrate and a second substrate facing a cell, where the first substrate is a reflection type array substrate as described above, and the second substrate includes a substrate and an electrode layer.

The embodiment of the invention also provides a preparation method of the reflection-type array substrate, which comprises the following steps:

preparing an array structure layer on one side of a substrate;

preparing a structural color layer on one side of the array structural layer, which deviates from the substrate base plate, wherein the structural color layer comprises a structural layer, the structural layer comprises a plurality of structural arrays, each structural array comprises a plurality of sub-arrays, each sub-array corresponds to one sub-pixel, and each sub-array consists of a plurality of nano-columns with the same height and is used for reflecting color light.

Optionally, the period of the nano-pillars in the sub-array for reflecting red light is 160 to 300nm, the height of the nano-pillars is 80 to 150nm, and the structural width of the nano-pillars is 80 to 150 nm; the period of the nano-pillars in the sub-array for reflecting the green light is 240-450 nm, the height of the nano-pillars is 80-150 nm, and the structural width of the nano-pillars is 80-150 nm; the period of the nano-pillars in the subarray for reflecting blue light is 320-600 nm, the height of the nano-pillars is 80-150 nm, and the structural width of the nano-pillars is 80-150 nm; or

The period of the nano-pillars in the subarray for reflecting red light is 150-200 nm, the height of the nano-pillars is 80-150 nm, and the structural width of the nano-pillars is 100-130 nm; the period of the nano-pillars in the sub-array for reflecting the green light is 150 to 200nm, the height of the nano-pillars is 80 to 150nm, and the structural width of the nano-pillars is 70 to 100 nm; the period of the nano-pillars in the subarray for reflecting blue light is 150 to 200nm, the height of the nano-pillars is 80 to 150nm, and the structural width of the nano-pillars is 40 to 70 nm.

According to the reflection-type array substrate, the preparation method thereof and the display device, the color layer for realizing the color display structure is arranged on the side, away from the substrate, of the array structure layer, and the color film substrate is not needed, so that the reflectivity is improved, and the power consumption is reduced.

Of course, not all of the advantages described above need to be achieved at the same time in the practice of any one product or method of the invention. Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the embodiments of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the example serve to explain the principles of the invention and not to limit the invention. The shapes and sizes of the various elements in the drawings are not to scale and are merely intended to illustrate the invention.

FIG. 1 is a schematic view of a reflective LCD;

FIG. 2 is a schematic structural diagram of a reflective display apparatus according to an embodiment of the disclosure;

fig. 3 is a schematic structural diagram of a reflective array substrate according to an embodiment of the disclosure;

FIG. 4 is a schematic diagram of the principle of F-B interference;

FIG. 5 is a schematic view of a reflective display device according to an embodiment of the disclosure;

FIG. 6 is a schematic diagram of an array of structures according to an embodiment of the present disclosure;

FIG. 7 is a cross-sectional view of a sub-array corresponding to red light in an embodiment of the present disclosure;

FIG. 8 is a cross-sectional view of a subarray corresponding to green light in an embodiment of the present disclosure;

fig. 9 is a cross-sectional view of a sub-array corresponding to blue light in an embodiment of the present disclosure.

Description of reference numerals:

1 — a first substrate; 2 — a second substrate; 3-liquid crystal;

10-a substrate base plate; 11-an array structure layer; 12-a structural color layer;

111-a gate electrode; 112-a gate insulating layer; 113-an active layer;

114-source drain electrodes; 115-a passivation layer; 116-pixel electrodes;

117 — a planarization layer; 121-structural layer; 122 — a protective layer;

20-a substrate base plate; 21-electrode layer.

Detailed Description

The following detailed description of embodiments of the invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

Fig. 1 is a schematic view of a structure of a reflective type LCD. The structure of the liquid crystal display device comprises a circular polarizer with a compensation Film, a CF (Color Filter) substrate, a liquid crystal layer, a TFT (Thin Film transistor) substrate and a reflective metal layer (not shown in the figure). Under the voltage opening state, the liquid crystal is twisted by 90 degrees, and natural light is reflected back to display a bright state; in the voltage-off state, the liquid crystal is twisted and aligned, and natural light cannot be reflected to show a dark state. However, the reflective display has a low reflectivity due to the introduction of CF, and has a problem of low brightness when natural light is used as a light source, and if a front light source is used as a light source, the power consumption is relatively high.

To solve the technical problem of low brightness of the existing reflective LCD, the embodiment of the present disclosure provides a reflective array substrate, which includes a substrate, an array structure layer and a structure color layer stacked in sequence, wherein the structure color layer includes a structure layer, the structure layer includes a plurality of structure arrays, each structure array includes a plurality of sub-arrays, each sub-array corresponds to one sub-pixel, each sub-array is composed of a plurality of nano-pillars with the same height, and each sub-array is used for reflecting one color light.

Each sub-array corresponds to one sub-pixel, that is, each sub-array corresponds to a pixel electrode of the array structure layer, and the projection of the sub-array on the substrate may be greater than or equal to the projection of the pixel electrode on the substrate.

In an exemplary embodiment, the structural color layer may further include a protective layer on the structural layer.

In an exemplary embodiment, the structural layer is implemented using a super-surface structure.

In an exemplary embodiment, each sub-array has the same size, and in order to enable different sub-arrays in the same structural array to emit light of different colors, the specifications of the nano-pillars in each sub-array need to be adjusted, that is, the nano-pillars in a plurality of sub-arrays in one structural array are all different in design, in one design manner, for any two sub-arrays in one structural array, the nano-pillars in the two sub-arrays have the same size (the height and the diameter of the nano-pillars are the same), but the arrangement periods are different (that is, the inter-pillar intervals are different), that is, the number of the nano-pillars in each sub-array in one structural array is different. In another design, for any two sub-arrays in a structural array, the nano-pillars of the two sub-arrays have different sizes (e.g., the heights are the same, and the diameters of the nano-pillars are different), the arrangement period may be the same, and the number of the nano-pillars in each sub-array is also different.

For example, the period of the nano-pillars in the sub-array for reflecting red light is 160 to 300nm, the height of the nano-pillars is 80 to 150nm, and the structural width of the nano-pillars is 80 to 150 nm; the period of the nano-pillars in the sub-array for reflecting the green light is 240-450 nm, the height of the nano-pillars is 80-150 nm, and the structural width of the nano-pillars is 80-150 nm; the period of the nano-pillars in the subarray for reflecting blue light is 320-600 nm, the height of the nano-pillars is 80-150 nm, and the structural width of the nano-pillars is 80-150 nm; or

Fig. 2 is a schematic structural view of a reflective LCD according to an embodiment of the present disclosure, and as shown in fig. 2, a main structure of the reflective LCD according to an embodiment of the present disclosure includes a first substrate 1 and a second substrate 2 facing each other, a liquid crystal 3 is filled between the first substrate 1 and the second substrate 2, and the second substrate 2 includes a base substrate 20 and an electrode layer 21 (e.g., a common electrode layer) formed on the base substrate 20. The first substrate 1 is an array substrate and comprises a substrate 10, an array structure layer 11 and a structure color layer 12, wherein the array structure layer 11 is arranged on one surface of the substrate 10 facing the second substrate 2, and the structure color layer 12 is arranged on one side of the array structure layer 11 departing from the substrate 10. In the present embodiment, the reflective LCD is backlit by ambient light, the structural color layer 12 is used to reflect the ambient light and convert the ambient light into light of different colors, and the reflective LCD is backlit by the ambient light, so as to realize the display of color images. According to the embodiment of the disclosure, the structural color layer is adopted to replace the color film layer, so that the reflectivity and the display brightness can be improved, the process flow is reduced, and the cost is saved compared with the scheme of using the color film layer. Because the ambient light is used as the backlight, the efficiency can be reduced compared with the scheme of using a front light source as a light source.

The LCD may be classified into a Twisted Nematic (TN) display mode, an In Plane Switching (IPS) display mode, a Fringe Field Switching (FFS) display mode, and an Advanced Super Dimension Switching (ADS) display mode, etc., according to the display mode. The technical solution of the embodiment of the present invention is described below by taking a TN display mode reflective LCD as an example, but the application of the embodiment of the present disclosure is not limited thereto, and the present disclosure may be applied to reflective LCDs of other display modes.

Fig. 3 is a schematic structural diagram of a reflective array substrate according to an embodiment of the disclosure. As shown in fig. 3, the reflective array substrate of the present embodiment includes a substrate 10, an array structure layer 11 disposed on a front surface of the substrate 10, and a structure color layer 12 disposed on a surface of the array structure layer 11 facing away from the substrate. In this embodiment, "front" refers to the surface of the reflective LCD that faces the viewer when in use, from which ambient light is incident, and "back" refers to the surface that faces away from the viewer. The structural color layer 12 includes a structural layer 121 and a protective layer 122. The structure layer 121 is disposed on the front surface of the array structure layer 11, and the protective layer 122 is disposed on the structure layer 121 for protecting the structure layer. The array structure layer 11 includes a gate electrode 111, a gate insulating layer 112, an active layer 113, a source/drain electrode 114, a passivation layer 115, a pixel electrode 116, and a planarization layer 117, which are sequentially disposed on the substrate 10, and the pixel electrode is connected to the source electrode or the drain electrode through a via hole formed in the passivation layer. Wherein the gate electrode, the active layer and the source and drain electrodes form a thin film transistor. Through the switch of the thin film transistor, data signal voltages with different sizes are respectively input to each pixel, and the rotation states of liquid crystal molecules under different voltages are different, so that different emergent light brightness is realized. A voltage is applied across the liquid crystal molecules via the pixel electrode 116 and the electrode layer 21.

The reflective array substrate of the embodiment further comprises a plurality of gate lines and a plurality of data lines formed on the substrate, wherein each row of gate lines is vertically intersected with each column of data lines, a plurality of pixel regions arranged in an array are formed on the substrate, each region of pixels is provided with a thin film transistor and a pixel electrode, the gate lines are used for providing scanning signals for the corresponding thin film transistors, and the thin film transistors are conducted in response to the scanning signals of the gate lines, so that voltages from the data lines are applied to the pixel electrodes.

The embodiment of the disclosure is realized based on the F-B interference principle, and determines the color of the reflected light by using the interference effect, that is, when a certain color light is interfered and is constructive, other color lights are destructive to interfere, and the formula for constructive and destructive interference is as follows:

where Δ L is an optical path difference, e is a thickness of the incident layer, n' is a refractive index of the air layer, n is a refractive index of the incident layer, λ is a wavelength of light, i is an incident angle, and K is an interference order.

The coherent light wave intensity (I) can be expressed as:

wherein I₁And I₂The light intensities of two lines of light waves respectively,

is the phase difference between the phase difference and the phase difference,

referred to as the interference factor.

Fig. 4 is a schematic diagram of the principle of interference, where the distance between the first surface and the second surface is D, the refractive index of the medium 1 between the first surface and the second surface is n1, the refractive index of the medium 2 above the second surface is n2, the light ray a emitted to the second surface reflects the light ray D at the second surface, and the light ray a refracts the light ray C emitted from the second surface through the medium 1 at the second surface, and with reference to equation 1, when the optical path between the light ray C and the light ray D is an integer multiple of the wavelength of the light ray, the light ray interference is constructive, and when the optical path is an integer multiple of the wavelength of the light ray 1/2, the light ray interference cancellation occurs.

In the disclosed embodiment, structure layer 121 may be implemented using a super surface. Based on the principle that the super-surface structure can change the refractive index, color display with high uniformity can be realized. According to the refractive index difference of the super-surface with different structures, based on the formula 1, only light with fixed wavelength (such as red light, green light or blue light) can be reflected by the super-surface (i.e. interference constructive) by adopting the super-surface structure with different refractive indexes.

Fig. 5 is a schematic diagram of a reflective display structure provided in the embodiment of the present disclosure, in which super surface structures of different specifications are fabricated on the array structure layer 11, and based on the F-B principle, RGB display with different colors can be implemented, so as to replace a conventional CF layer in an original structure, avoid brightness loss, and have the advantages of high reflectivity and high brightness.

Fig. 6 is a schematic top view of a super-surface structure corresponding to one pixel (including three sub-pixels RGB), and fig. 6 shows a structure array including a plurality of sub-arrays (shown as R sub-array, G sub-array, and B sub-array), each sub-array corresponding to one sub-pixel, for implementing reflection of light of one color. In this embodiment, each subarray may be composed of a different number of nano-pillars, the nano-pillars may be on the order of half a wavelength (e.g., hundreds of nanometers), and the height of the nano-pillars in each subarray is the same. The nanopillars may be cylindrical. The cross-section of the nano-pillars may be square or may be rectangular. The super surface material can be a material with high reflectivity, such as silver (Ag), and can also function as a reflective metal layer.

Fig. 7 to 9 are examples of structural layers for implementing different color displays in the embodiment of the present disclosure, where fig. 7 is a cross-sectional example of a sub-array reflecting red light (R), and specifications of nano-pillars in a super-surface structure corresponding to the reflecting red light are as follows: the period of the nanopillars is 160 to 300nm, the period being used to define a space between adjacent two nanopillars, the height of the nanopillars (i.e., the nanopillar height) is 80 to 150nm, and the structural width of the nanopillars (i.e., the diameter of the nanopillars) is 80 to 150 nm. Fig. 8 is a cross-sectional example of a sub-array reflecting green light (G), and the specifications of the nano-pillars in the super-surface structure corresponding to the green light reflection are: the period is 240-450 nm, the height is 80-150 nm, and the structure width is 80-150 nm; fig. 9 is a cross-sectional view of a subarray reflecting blue light (B), where the specifications of the nano-pillars in the super-surface structure corresponding to the reflected blue light are: the period is 320-600 nm, the height is 80-150 nm, and the structure width is 80-150 nm.

The arrangement of fig. 6 to 9 is merely an example. Besides the above, under the condition of a certain height, the reflection of different colors can be realized by changing the specification of the nano-pillar structures in different sub-pixels. The period of the nano-pillar structure is unchanged, the larger the diameter of the nano-pillar corresponding to different colors is, the half-peak width red shift is, that is, the wider the nano-pillar reflecting red light is compared with the nano-pillar reflecting green light. For example, when the period of the nanopillar is 150 to 200nm, the structure width of the nanopillar reflecting red light is 100 to 130nm, the structure width of the nanopillar reflecting green light is 70 to 100nm, and the structure width of the nanopillar reflecting blue light is 40 to 70 nm. The heights of the nano-columns reflecting the three colors are the same and are all 80 to 150 nm. The above is merely an example, and in practical application, the range may be adjusted based on factors such as the structure of each film layer, the material, and the period of the nano structure, so as to ensure the reflection effect.

The technical solution of this embodiment is described below through the array substrate preparation process.

The preparation method of the array substrate comprises the following steps:

s10, preparing an array structure layer on one side of the substrate;

s20, preparing a structural color layer on one side of the array structural layer, which is far away from the substrate base plate, wherein the structural color layer comprises a structural layer, the structural layer comprises a plurality of structural arrays, each structural array comprises a plurality of sub-arrays, each sub-array corresponds to one sub-pixel, and each sub-array comprises a plurality of nano-columns with the same height and is used for reflecting one color light.

In this embodiment, an array structure layer is first prepared on one side surface of a substrate base by a patterning process, and after the preparation of the array structure layer is completed, a structure color layer is prepared on the array structure layer. The "patterning process" referred to in this embodiment includes processes of depositing a film layer, coating a photoresist, mask exposure, development, etching, stripping a photoresist, and the like. The preparation of the array structure layer includes forming a thin film transistor, a gate line and a data line, a gate insulating layer, a passivation layer and a pixel electrode on a substrate, and may further include other film layers, such as a planarization layer, etc., which are known to those skilled in the art based on the common general knowledge and the prior art, and are not limited herein.

In this embodiment, after the array structure layer is prepared on one side of the substrate, the structure color layer is prepared on one side of the array structure layer away from the substrate. Depositing a metal film, such as a silver metal film, with a thickness of 150-500 nm on the side of the array structure layer away from the substrate, imprinting the nanostructure made of the imprinting adhesive material by a nanoimprint process, and performing pattern transfer of the nanostructure by an etching process to form a silver nanorod structure array, i.e. a structure layer, with a height of 80-150 nm. The structural layer comprises a plurality of structural arrays, each structural array comprises a plurality of sub-arrays, each sub-array corresponds to one sub-pixel, and the orthographic projection of each sub-array on the substrate can be larger than or equal to the orthographic projection of one pixel electrode in the array structural layer on the substrate. And coating a layer of organic material with the thickness of 0.5-10 μm on the formed structural layer to form a protective layer covering the structural layer, wherein the protective layer simultaneously serves as a flat layer, so that the front surface of the first substrate is flattened. The metal thin film may be made of a metal material having a high reflectance, and may be made of metal Al (aluminum) or aluminum neodymium alloy (AlNd) in addition to the silver (Ag). The protective layer may be made of a transparent polymer such as epoxy resin or acrylic resin. The deposition may be performed by magnetron sputtering, evaporation, and the like, and the coating and imprinting may be performed by known coating and imprinting processes, which are not specifically limited herein.

According to the reflection-type array substrate provided by the embodiment, the structural color layer is arranged on the array structural layer, and the light reflection layer is formed after the process of forming the array structural layer, so that the existing preparation process is not required to be greatly changed, the difficulty of the preparation process of the reflection-type LCD is reduced, and the light reflection effect can be effectively ensured.

Based on the same inventive concept, embodiments of the present disclosure also provide a reflective LCD, which includes the reflective array substrate of any one of the foregoing embodiments, and a second substrate aligned with the reflective array substrate. The reflective LCD may be: products or components with display functions such as mobile phones, notebook computers, digital cameras, navigators, personal digital assistants and the like are not repeated.

In the description of the embodiments of the present invention, it should be understood that the terms "middle", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the embodiments of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Although the embodiments of the present invention have been described above, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A reflective array substrate, comprising a substrate substrate, an array structural layer and a structural color layer stacked in sequence, the structural color layer comprising a structural layer, the structural layer comprising a plurality of structural arrays, each structural array comprising A plurality of sub-arrays, each sub-array corresponds to a sub-pixel, and each sub-array is composed of a plurality of nano-pillars with the same height for reflecting light of one color.

2 . The reflective array substrate according to claim 1 , wherein the structure layer is a metasurface structure. 3 .

3. The reflective array substrate according to claim 2, wherein,

The period of the nano-pillars in the sub-array for reflecting red light is 160 to 300 nm, the height of the nano-pillars is 80 to 150 nm, and the structure width of the nano-pillars is 80 to 150 nm;

The period of the nano-pillars in the sub-array for reflecting green light is 240 to 450 nm, the height of the nano-pillars is 80 to 150 nm, and the structure width of the nano-pillars is 80 to 150 nm;

The period of the nanopillars in the subarray for reflecting blue light is 320 to 600 nm, the height of the nanopillars is 80 to 150 nm, and the structure width of the nanopillars is 80 to 150 nm.

4. The reflective array substrate according to claim 2, wherein,

The period of the nano-pillars in the sub-array for reflecting red light is 150 to 200 nm, the height of the nano-pillars is 80 to 150 nm, and the structure width of the nano-pillars is 100 to 130 nm;

The period of the nano-pillars in the sub-array for reflecting green light is 150 to 200 nm, the height of the nano-pillars is 80 to 150 nm, and the structure width of the nano-pillars is 70 to 100 nm;

The period of the nanopillars in the subarray for reflecting blue light is 150 to 200 nm, the height of the nanopillars is 80 to 150 nm, and the structure width of the nanopillars is 40 to 70 nm.

5 . The reflective array substrate according to claim 1 , wherein the structural color layer further comprises a protective layer on the structural layer. 6 .

6. The reflective array substrate according to any one of claims 1-4, wherein,

The array structure layer includes a gate electrode, a gate insulating layer, an active layer, a source-drain electrode, a passivation layer, a pixel electrode and a planarization layer that are sequentially arranged on the base substrate.

7. The reflective array substrate according to claim 2, wherein the material of the metasurface structure comprises aluminum, silver or aluminum-neodymium alloy.

8. A display device, characterized in that it comprises a cell-aligned first substrate and a second substrate, the first substrate is the reflective array substrate according to any one of claims 1-7, the second substrate is The substrate includes a base substrate and an electrode layer.

9. A method for preparing a reflective array substrate, comprising:

An array structure layer is prepared on one side of the base substrate;

A structural color layer is prepared on the side of the array structure layer facing away from the base substrate. The structural color layer includes a structure layer, and the structure layer includes a plurality of structure arrays, each structure array includes a plurality of sub-arrays, and each sub-array corresponds to a sub-array Pixels, each sub-array consisting of multiple nanopillars of the same height, are used to reflect light of one color.

10. preparation method according to claim 9, is characterized in that,

The period of the nanopillars in the subarray for reflecting red light is 160 to 300 nm, the height of the nanopillars is 80 to 150 nm, and the structural width of the nanopillars is 80 to 150 nm; the period of the nanopillars in the subarray for reflecting green light is 240 to 450 nm, the height of the nano-pillars is 80 to 150 nm, and the structural width of the nano-pillars is 80 to 150 nm; the period of the nano-pillars in the sub-array for reflecting blue light is 320 to 600 nm, the height of the nano-pillars is 80 to 150 nm, and the nano-pillars are The structure width of 80 to 150nm; or

The period of the nanopillars in the subarray for reflecting red light is 150 to 200 nm, the height of the nanopillars is 80 to 150 nm, and the structure width of the nanopillars is 100 to 130 nm; the period of the nanopillars in the subarray for reflecting green light is is 150 to 200 nm, the height of the nanopillars is 80 to 150 nm, and the structural width of the nanopillars is 70 to 100 nm; the period of the nanopillars in the sub-array for reflecting blue light is 150 to 200 nm, and the height of the nanopillars is 80 to 150 nm, The structure width of the nanopillars is 40 to 70 nm.