Display panel and preparation method therefor, application of display panel, and ar near-eye display apparatus

Abstract

A display panel (10) and a preparation method therefor, application of the display panel (10), and an AR near-eye display apparatus (1). The display panel (10) comprises a substrate (100), a light-emitting pixel (200) and a metasurface structure layer (300), wherein the metasurface structure layer (300) is arranged on a light-emitting side of the light-emitting pixel (200), and the metasurface structure layer (300) is configured to perform phase modulation on a first beam, which is emitted from the light-emitting pixel (200) to the metasurface structure layer (300), such that a second beam emitted from the metasurface structure layer (300) has collimation and directionality. The light-emitting pixel (200) comprises sub-pixels (201, 202, 203) in three colors, so as to emit RGB light; the metasurface structure layer (300) comprises three metasurface units (301, 302, 303); the sub-pixels (201, 202, 203) are aligned with and bonded to the metasurface units (301, 302, 303) on a one-to-one basis; and each of the metasurface units (301, 302, 303) performs phase modulation on light in one of the three colors.

Description

Display panels and their manufacturing methods, applications of display panels, AR near-eye display devices

[0001] This application claims priority to Chinese Patent Application No. 2024115809120, filed with the State Intellectual Property Office of China on November 7, 2024, entitled "Display Panel and Method for Preparing the Same Thereof, Application of the Display Panel, AR Near-Eye Display Device", the entire contents of which are incorporated herein by reference.

[0002] Technical Field

[0003] This invention relates to the field of display technology, and in particular to a display panel and its manufacturing method, the application of the display panel, and an AR near-eye display device. Background Technology

[0004] Display pixels typically exhibit a Lambertian angle emission pattern, including standard light-emitting diode (LED) chips such as Micro LEDs, as well as Organic Light-Emitting Diodes (OLEDs) and silicon-based OLEDs, and this characteristic is wavelength-independent. For certain display applications, collimated and directional light emission may be beneficial or necessary. For example, light emitted from infrared (IR) LEDs for iris scanning requires collimation; OLEDs and quantum dot LEDs have low light extraction efficiency and also require microlenses for focusing to improve pixel brightness; naked-eye 3D light field displays require directional emission of light from each pixel to the human eye to form discrete viewpoints, which involves light collimation and directional emission.

[0005] For naked-eye light field 3D displays, cylindrical lens arrays or microlens arrays are typically used to achieve directional light emission. These lenses utilize the principles of geometric optics, generally require a large volume and thickness, and due to poor directionality, the display effect has significant aberrations and crosstalk. Summary of the Invention

[0006] The present invention provides a display panel, its manufacturing method and application, and an AR near-eye display device to solve the technical problems that for naked-eye light field 3D display, the optical engine generally requires a large volume and thickness, and the poor light output directionality of the optical engine leads to a large difference in display effect and crosstalk.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a display panel, comprising:

[0009] substrate;

[0010] Multiple light-emitting pixels are disposed on one side of the substrate, and the light-emitting pixels emit RGB three-color light;

[0011] A metasurface structure layer is disposed on the light-emitting side of the light-emitting pixel. The metasurface structure layer is configured to perform phase modulation on a first light beam emitted from the light-emitting pixel to the metasurface structure layer, so that a second light beam emitted from the metasurface structure layer has collimation and directionality.

[0012] The light-emitting pixel includes three colors of sub-pixels, and the metasurface structure layer includes multiple spaced arrays of metasurface units with three different phases. The three colors of sub-pixels are respectively paired with the metasurface units of the three phase structures, so that the metasurface unit corresponding to one phase structure modulates the phase of light of one color; the metasurface unit modulates the phase of the light emitted by the corresponding sub-pixel, satisfying the following formulas (1) to (3):

[0013]

[0014] In formula (1), For phase delay, For collimation delay phase; For phases deflected to different angles;

[0015] In formula (2), f is the focal length, ni is the refractive index of the medium through which the light rays incident on different metasurface units pass, and in formulas (2) and (3), λ represents the wavelength of the corresponding incident light rays, and x / y / z represents the spatial coordinates of the metasurface structure.

[0016] In formula (3), This represents the angle between the Z-axis and the projection of the deflected beam onto the XZ plane; The angle between the Z-axis and the projection of the deflected beam onto the YZ plane is represented; no represents the refractive index of the exit medium.

[0017] In one embodiment, the display panel includes a microlens array layer stacked on the light-emitting surface of the substrate, and the microlens array layer is located between the light-emitting pixels and the metasurface structure layer.

[0018] In one embodiment, the display panel further includes a protective adhesive layer filled between the metasurface units; and / or, the display panel further includes encapsulation glass stacked on the side of the metasurface structure layer opposite to the substrate.

[0019] In one embodiment, each of the metasurface units has a columnar geometry or a ring geometry.

[0020] Secondly, the present invention provides a method for manufacturing a display panel, comprising the following steps:

[0021] Prepare a substrate, and form light-emitting pixels on one side of the substrate;

[0022] Design a metasurface structure layer based on the coupled-wave method and the finite-difference time-domain method, wherein the coupled-wave method is used for unit structure design and the finite-difference time-domain method is used for overall structure design and verification.

[0023] The metasurface structure layer is formed on the side of the light-emitting pixel facing away from the substrate. The metasurface structure layer is configured to perform phase modulation on a first light beam emitted from the light-emitting pixel to the metasurface structure layer, so that a second light beam emitted from the metasurface structure layer has collimation and directionality.

[0024] The light-emitting pixel includes sub-pixels of three colors, and the metasurface structure layer includes multiple spaced and arrayed metasurface units with three different phases. The sub-pixels of the three colors are respectively paired with the metasurface units of the three phase structures, so that the metasurface unit corresponding to one phase structure modulates the phase of light of one color; the metasurface unit modulates the phase of the light emitted by the corresponding sub-pixel, satisfying the following formulas (1) to (3):

[0025]

[0026] In formula (1), For phase delay, For collimation delay phase; For phases deflected to different angles;

[0027] In formula (2), f is the focal length, and n i λ is the refractive index of the medium through which the light incident on the metasurface structure layer passes. In formulas (2) and (3), λ represents different wavelengths, and x / y / z represents the spatial coordinates of the metasurface structure.

[0028] In formula (3), This represents the angle between the Z-axis and the projection of the deflected beam onto the XZ plane; This represents the angle between the Z-axis and the projection of the deflected beam onto the YZ plane; n o It represents the refractive index of the outgoing medium.

[0029] In one embodiment, designing the metasurface structure layer includes the following steps:

[0030] Based on the parameters of the luminescent pixel, a metasurface structure layer matching the luminescent pixel is constructed; the phase distribution information of the metasurface structure is extracted.

[0031] The phase distribution information is discretized based on the periodic size of the metasurface unit library to obtain the phase discretization result;

[0032] The metasurface unit structure library corresponds to the emission spectrum range of the light-emitting pixel and includes multiple metasurface unit structures. Each metasurface unit structure corresponds to a phase value in the range of 0 to 2π, and the phase values ​​corresponding to each metasurface unit structure are different.

[0033] The metasurface unit array is arranged according to the phase discretization results to construct the metasurface structure layer.

[0034] In one embodiment, forming the metasurface structure layer includes the following steps:

[0035] A metasurface film and a hard mask layer are sequentially deposited on the light-emitting surface of the substrate;

[0036] Patterning and etching are performed sequentially on the hard mask layer to transfer the pattern on the hard mask layer onto the metasurface film layer;

[0037] Remove the hard mask layer to form the metasurface structure layer;

[0038] The metasurface structure layer includes multiple metasurface units that match the wavelengths of the RGB primary color light.

[0039]

[0040] Thirdly, the present invention provides an application of a display panel, wherein the display panel described in any of the preceding embodiments or the display panel obtained by any of the method embodiments is applied to naked-eye 3D light field display.

[0041] Fourthly, the present invention provides an AR near-eye display device, comprising:

[0042] Optical waveguides have both coupling-in and coupling-out structures;

[0043] The display panel described in any of the preceding embodiments or the display panel prepared by any of the preceding methods, wherein the display panel serves as a light source device and is disposed on one side of the coupling structure of the optical waveguide, and the light emitted by the display panel enters the optical waveguide through the coupling structure and propagates to the coupling structure and exits.

[0044] In one embodiment, the coupling structure includes a geometric coupling device, wherein the metasurface structure layer is spaced apart from the geometric coupling device or the metasurface structure layer is attached to the mirror surface of the geometric coupling device.

[0045] As can be seen from the above technical solutions, the embodiments of the present invention have at least the following advantages and positive effects:

[0046] This invention relates to a display panel, its fabrication method and application, and an AR near-eye display device. The display panel includes a substrate, light-emitting pixels, and a metasurface structure layer stacked sequentially. The metasurface structure layer is disposed on the light-emitting side of the light-emitting pixels and is configured to phase-modulate a first light beam emitted from the light-emitting pixels to the metasurface structure layer, thereby enabling a second light beam emitted from the metasurface structure layer to possess collimation and directionality. Specifically, the light-emitting pixels include sub-pixels of three colors to emit RGB light, and the metasurface structure layer includes three metasurface units. Each color sub-pixel is respectively paired with a different metasurface unit, so that each metasurface unit phase-modulates one color of light. On the one hand, the metasurface structure layer enables the collimation and directionality of light emitted from the display panel, thereby improving luminous efficiency and brightness and reducing light crosstalk. These advantages enable the display panel of this application to achieve better naked-eye 3D light field display. On the other hand, the metasurface structure layer is composed of metasurface unit structure groups with a scale smaller than the wavelength of incident light arranged according to a certain arrangement rule. The thickness is small at the micro-nano level, which is conducive to achieving the thinness of the display panel.

[0047] Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0049] Figure 1 shows a schematic diagram of the existing LED display optical path (a) and a schematic diagram of the LED divergence angle distribution (b).

[0050] Figure 2 is a schematic diagram of the display optical path (a) and a schematic diagram of the divergence angle distribution of the LED integrated with the microlens array shown in Figure 1 (b).

[0051] Figure 3 is a schematic diagram of the optical path of a display panel according to an embodiment of this application (a) and a schematic diagram of the divergence angle distribution of the light-emitting pixels (b).

[0052] Figure 4 is a schematic diagram of the display panel shown in Figure 3;

[0053] Figure 5 is a schematic diagram of the optical path and structure of a display panel according to another embodiment of this application;

[0054] Figure 6 is a flowchart of a method for preparing a display panel according to an embodiment of this application;

[0055] Figure 7 shows the step-by-step flow of the metasurface structure layer design in the preparation process shown in Figure 6;

[0056] Figure 8 shows the steps involved in the formation of the metasurface structure in the preparation process shown in Figure 6.

[0057] Figure 9 is a schematic diagram of the optical path and structure of a display panel applied to naked-eye 3D light field display according to an embodiment of this application;

[0058] Figure 10 is a schematic diagram of the optical path and structure of an AR near-eye display device according to an embodiment of this application;

[0059] Figure 11 is a schematic diagram of the optical path and structure of an AR near-eye display device according to another embodiment of this application.

[0060] The annotations in the attached figures are explained as follows:

[0061] 1. AR near-eye display device; 12. Light source device;

[0062] 10. Display panel; 100. Substrate; 200. Light-emitting pixel; 201. Red sub-pixel; 202. Green sub-pixel; 203. Blue sub-pixel; 300. Metasurface structure layer; 301. Red metasurface unit; 302. Green metasurface unit; 303. Blue metasurface unit; 400. Microlens structure layer; 500. Protective adhesive layer; 600. Encapsulation glass;

[0063] 20. Optical waveguide; 21. Coupled structure; 211. Mirror; 212. Prism. Detailed Implementation

[0064] Typical embodiments embodying the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various variations in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations herein are for illustrative purposes only and not intended to limit the present invention.

[0065] Furthermore, the terms "first" and "second" 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0066] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "setup," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0067] Display pixels typically have a Lambertian angle emission pattern, including standard light-emitting diode (LED) chips such as microLEDs, as well as organic light-emitting diodes (OLEDs) and silicon-based OLEDs, and this characteristic is independent of wavelength. In some display applications, the light emitted by the light-emitting pixel 200 is required to have collimation and directionality. It should be noted that the collimation of light means that the beam of light is modulated from divergent light into a parallel beam, and the directionality of light means that the beam of light is modulated to be emitted at a preset angle. Figure 1 illustrates that current LED pixels typically have a Lambertian angle emission pattern, and their luminous energy distribution is Lambertian, with the emitted light having neither collimation nor directionality. Figure 2(a) illustrates that integrating a microlens array above the light-emitting pixel increases the collimation of the light emission. After adding the microlens array, the collimation is improved, the emission angle range is reduced, and the brightness of the emitted light is increased. However, this method has crosstalk between adjacent pixels and increases the thickness of the display device or the display optical engine itself.

[0068] Therefore, in order to achieve collimation and directionality of light emission from LED pixels, and at the same time meet the requirements for thinner and lighter display devices or display optical engines, this application provides a display panel 10.

[0069] Referring to Figures 3 and 4, the display panel 10 includes a substrate 100, light-emitting pixels 200, and a metasurface structure layer 300. Multiple light-emitting pixels 200 are disposed on one side of the substrate 100. The light-emitting pixels 200 include, but are not limited to, light-emitting elements such as LEDs, OLEDs, and quantum dots. The metasurface structure layer 300 is disposed on the light-emitting side of the light-emitting pixels 200. The metasurface structure layer 300 is configured to phase-modulate the first beam of light emitted from the light-emitting pixels 200 to the metasurface structure layer 300, so that the second beam of light emitted from the metasurface structure layer 300 has extremely high collimation and directionality (as shown in Figure 3(a)). The metasurface structure layer 300 is composed of metasurface unit structures with a scale smaller than the wavelength of the incident light arranged according to a certain arrangement rule. The metasurface structure layer 300 is typically a micro / nano structure (GaN, TiO, SiN, etc.) constructed on a substrate material (SiO2, AO3, etc.). The metasurface structure layer 300, with its micro-nano structure optical modulation characteristics, can accurately modulate the phase of incident light, thereby achieving precise control of the incident light. It features strong design flexibility, small structural size, and precise light control.

[0070] Specifically, in Figure 4, the luminescent pixel 200 includes three color sub-pixels: red sub-pixel 201, green sub-pixel 202, and blue sub-pixel 203. The metasurface structure layer 300 is composed of multiple metasurface unit arrays, including three different metasurface unit structures: red metasurface unit 301, green metasurface unit 302, and blue metasurface unit 303. The red metasurface unit 301 is aligned and bonded to the red sub-pixel 201, and the red metasurface unit 301 performs phase modulation on the red light emitted by the red sub-pixel 201; the green metasurface unit 302 is aligned and bonded to the green sub-pixel 202, and the green metasurface unit 302 performs phase modulation on the green light emitted by the green sub-pixel 202; the blue metasurface unit 303 is aligned and bonded to the blue sub-pixel 203, and the blue metasurface unit 303 performs phase modulation on the blue light emitted by the blue sub-pixel 203. That is, each metasurface unit of each structure performs phase modulation on light of one color, and each metasurface unit performs phase modulation on the light emitted by the corresponding sub-pixel, satisfying the following formulas (1) to (3):

[0071]

[0072] In formula (1), For phase delay, For collimation delay phase; For phases deflected to different angles;

[0073] In formula (2), f is the focal length, and n iλ represents the refractive index of the medium through which the light rays incident on different metasurface units pass. In formulas (2) and (3), λ represents the wavelength of the corresponding incident light ray, and x / y / z represents the spatial coordinates of the metasurface structure.

[0074] In formula (3), This represents the angle between the Z-axis and the projection of the deflected beam onto the XZ plane; This represents the angle between the Z-axis and the projection of the deflected beam onto the YZ plane; n o It represents the refractive index of the outgoing medium.

[0075] Referring to Figure 7, the specific steps for designing the metasurface structure layer during the fabrication of the display panel 10 are as follows:

[0076] S21, Collimation and deflection phase design: Based on the parameters of the light-emitting pixel, construct a metasurface structure layer that matches the light-emitting pixel, and extract the phase distribution information of the metasurface structure;

[0077] S22, Phase discretization: The phase distribution information is discretized based on the periodic size of the metasurface unit library to obtain the phase discretization result;

[0078] S23, Construct a metasurface unit structure library. The metasurface unit structure library corresponds to the emission spectrum range of the luminescent pixel and includes multiple metasurface unit structures. Each metasurface unit structure corresponds to a phase value in the range of 0 to 2π. The phase values ​​corresponding to each metasurface unit structure are different.

[0079] S24. Construct a metasurface structure layer by arranging the metasurface unit array according to the phase discretization result.

[0080] In one embodiment, the phase distribution information is discretized according to the periodic size of the metasurface unit structure library, including: using the period of the metasurface unit structure as the smallest division scale to divide the phase distribution information, so that the phase distribution information is discretized into phase values ​​in the range of 0 to 2π.

[0081] Referring to Figure 8, the specific steps for forming the metasurface structure layer 300 during the fabrication of the display panel 10 are as follows:

[0082] S31, deposit two thin films: on the light-emitting pixel 200 material layer (the light-emitting surface of the substrate 100), a metasurface material thin film (which can be SiNx, nanoimprint stencil, etc.) and a hard mask thin film (aluminum Al, titanium Ti, chromium Cr, etc.) are deposited sequentially;

[0083] S32, Patterning process: The hard mask film is patterned to form a pattern of metasurface structure and thus form a hard mask layer.

[0084] S33, Etching: Using the hard mask layer as a mask, the metasurface material film is etched to transfer the pattern of the hard mask layer onto the metasurface material film.

[0085] S34, clean and then remove the hard mask layer to form a metasurface structure layer;

[0086] The metasurface structure layer 300 includes multiple metasurface unit structures that match the wavelengths of the RGB primary color light.

[0087] Preferably, in this embodiment, the one-to-one alignment of the metasurface unit and the sub-pixel can be achieved using a high-precision alignment bonding technique, which aligns and bonds the metasurface structure layer with the light-emitting pixel. Alignment marks are simultaneously fabricated during the fabrication of the light-emitting unit, and these marks are referenced during subsequent processing of the metasurface structure to achieve pixel alignment.

[0088] Thirdly, 3D display is a technology capable of displaying scenes and objects with a sense of depth, allowing observers to directly observe 3D images with physical depth. Currently, 3D display technologies mainly include glasses-free and device-assisted displays. Among them, glasses-free 3D display technology has attracted much attention due to its advantages of not requiring glasses or other auxiliary devices and its convenience and flexibility. Glasses-free 3D display technology is a light field display technology. It projects coded light field information onto different locations in space through light field modulation devices, forming a true 3D light field with continuous parallax at different locations in space, simultaneously providing stereoscopic parallax in multiple directions such as horizontal and vertical. Traditional glasses-free 3D display devices are mostly based on lens arrays and other devices. Limited by lens processing technology and refraction modulation models, their 3D viewing angle, 3D resolution, and display depth are constrained, resulting in large size and crosstalk leading to poor 3D display effects.

[0089] Therefore, referring to Figure 9, the present invention applies the display panel 10 provided in the previous embodiments or the display panel 10 prepared by the preparation method to a naked-eye 3D light field display. The substrate 100 and the light-emitting pixels 200 constitute a light source device 12, and the intensity angular spectrum of the light emitted by the light source device 12 follows a Lambertian distribution. The metasurface structure layer 300 is used to collimate and directionally emit the emitted light from each light-emitting pixel 200, and the emission direction is determined by the light field modulation rules of the light field display to reproduce a naked-eye visible 3D light field. The metasurface structure layer 300 is prepared based on superatoms and a phase template through electron beam exposure and reactive ion etching; wherein, the light source device 12 and the metasurface structure layer 300 are arranged sequentially in the optical path of the emitted light. The present invention has the advantages of small size, light weight, and low crosstalk, achieving a better naked-eye 3D light field display effect.

[0090] Fourthly, referring to Figures 10 or 11, this application also provides an AR near-eye display device 1, including an optical waveguide 20 and a display panel 10 as described in the previous embodiments or a display panel 10 prepared by the same method. The optical waveguide 20 has an insertion structure 21 and an output structure. The display panel 10 serves as a light-emitting device and is disposed on one side of the insertion structure 21 of the optical waveguide 20. Light emitted from the display panel 10 enters the optical waveguide 20 through the insertion structure 21 and propagates within it. The intensity angular spectrum of the light emitted from the display panel 10 follows a Lambertian distribution. The metasurface structure layer 300 collimates and directs the emitted light from each pixel before it propagates within the optical waveguide 20 and exits through the output structure. Therefore, the AR near-eye display device 1 of this application does not require a lens collimation system and can achieve higher-efficiency coupling with the optical waveguide. It should be noted that in this application, the output structure is not limited; it only needs to satisfy the requirement of coupling the light from the optical waveguide 20.

[0091] Preferably, in this embodiment, the coupling structure 21 is a geometric coupling device, such as a mirror 211 (as shown in FIG. 10) and a prism 212 (as shown in FIG. 11) used as the coupled geometric optical element. Since the metasurface structure layer 300 is composed of subwavelength nano-atoms, its volume is extremely small, and the emitted light from the metasurface structure layer 300 is pixelated and collimated, thus eliminating the need for a traditional lens collimation system and significantly reducing the overall system volume of the AR near-eye display device 1. Furthermore, the geometric coupling device, such as the mirror 211, can couple the incident light into the optical waveguide without loss, thereby solving the problem of low overall light energy utilization. It should be noted that when the geometric coupling device is a prism 212, the metasurface structure layer 300 can be attached to the mirror surface of the prism 212 or spaced apart from it. It should be understood that in other embodiments of this application, the coupling structure 21 can also be a coupling structure such as a diffraction grating.

[0092] The present invention provides a display panel 10, its fabrication method and application, and an AR near-eye display device 1. The display panel 10 includes a substrate 100, light-emitting pixels 200, and a metasurface structure layer 300 stacked sequentially. The metasurface structure layer 300 is disposed on the light-emitting side of the light-emitting pixels 200 and is configured to phase-modulate a first light beam emitted from the light-emitting pixels 200 to the metasurface structure layer 300, so that a second light beam emitted from the metasurface structure layer 300 has collimation and directionality. Specifically, the light-emitting pixels 200 include sub-pixels of three colors to emit RGB three-color light, and the metasurface structure layer 300 includes three metasurface units. Each color sub-pixel is respectively aligned and bonded to a different metasurface unit, so that each metasurface unit performs phase modulation on one color of light. On the one hand, the metasurface structure layer 300 achieves collimation and directionality of light emitted from the display panel 10, thereby improving luminous efficiency and brightness and reducing light crosstalk. These advantages enable the display panel 10 of this application to achieve better naked-eye 3D light field display, so the display panel 10 is applied to naked-eye 3D light field display. On the other hand, the metasurface structure layer 300 is composed of metasurface unit structure groups with a scale smaller than the wavelength of incident light arranged according to a certain arrangement rule. The thickness is small, at the micro-nano level, which is conducive to achieving the thinness of the display panel 10.

[0093] Although the invention has been described with reference to several typical embodiments, it should be understood that the terminology used is illustrative and exemplary, and not restrictive. Since the invention can be embodied in many forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims. Therefore, all variations and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. A display panel, characterized in that, include: substrate; Multiple light-emitting pixels are disposed on one side of the substrate, and the light-emitting pixels emit RGB three-color light; A metasurface structure layer is disposed on the light-emitting side of the light-emitting pixel. The metasurface structure layer is configured to perform phase modulation on a first light beam emitted from the light-emitting pixel to the metasurface structure layer, so that a second light beam emitted from the metasurface structure layer has collimation and directionality. The light-emitting pixel includes three colors of sub-pixels, and the metasurface structure layer includes multiple spaced arrays of metasurface units with three different phase structures. The three colors of sub-pixels are respectively paired with the three phase structures of the metasurface units, so that the metasurface unit corresponding to one phase structure modulates the phase of one color of light. The metasurface unit modulates the phase of the light emitted by the corresponding sub-pixel, satisfying the following formulas (1) to (3): In formula (1), For phase delay, For collimation delay phase; For phases deflected to different angles; In formula (2), f is the focal length, ni is the refractive index of the medium through which the light rays incident on different metasurface units pass, and in formulas (2) and (3), λ represents the wavelength of the corresponding incident light rays, and x / y / z represents the spatial coordinates of the metasurface structure. In formula (3), This represents the angle between the Z-axis and the projection of the deflected beam onto the XZ plane; The angle between the Z-axis and the projection of the deflected beam onto the YZ plane is represented; no represents the refractive index of the exit medium.

2. The display panel according to claim 1, characterized in that, The display panel includes a microlens array layer, which is stacked on the light-emitting surface of the substrate and located between the light-emitting pixels and the metasurface structure layer.

3. The display panel according to claim 1, characterized in that, The display panel further includes a protective adhesive layer filled between the metasurface units; and / or, the display panel further includes encapsulation glass stacked on the side of the metasurface structure layer opposite to the substrate.

4. The display panel according to claim 1, characterized in that, Each of the metasurface units has a columnar or annular geometry.

5. A method for manufacturing a display panel, characterized in that, Includes the following steps: Prepare a substrate, and form light-emitting pixels on one side of the substrate; Design a metasurface structure layer based on the coupled-wave method and the finite-difference time-domain method, wherein the coupled-wave method is used for unit structure design and the finite-difference time-domain method is used for overall structure design and verification. The metasurface structure layer is formed on the side of the light-emitting pixel facing away from the substrate. The metasurface structure layer is configured to perform phase modulation on a first light beam emitted from the light-emitting pixel to the metasurface structure layer, so that a second light beam emitted from the metasurface structure layer has collimation and directionality. The light-emitting pixel includes three colors of sub-pixels, and the metasurface structure layer includes multiple spaced and arrayed metasurface units with three different phase structures. The three colors of sub-pixels are respectively paired with the three phase structures of the metasurface units, so that the metasurface unit corresponding to one phase structure modulates the phase of one color of light. The metasurface unit modulates the phase of the light emitted by the corresponding sub-pixel, satisfying the following formulas (1) to (3): In formula (1), For phase delay, For collimation delay phase; For phases deflected to different angles; In formula (2), f is the focal length, ni is the refractive index of the medium through which the light incident on the metasurface structure layer passes, and in formulas (2) and (3), λ represents different wavelengths, and x / y / z represents the spatial coordinates of the metasurface structure. In formula (3), This represents the angle between the Z-axis and the projection of the deflected beam onto the XZ plane; The angle between the Z-axis and the projection of the deflected beam onto the YZ plane is represented; no represents the refractive index of the exit medium.

6. The method for manufacturing a display panel according to claim 5, characterized in that, Designing metasurface structural layers involves the following steps: Based on the parameters of the luminescent pixel, a metasurface structure layer matching the luminescent pixel is constructed; the phase distribution information of the metasurface structure is extracted. The phase distribution information is discretized based on the periodic size of the metasurface unit library to obtain the phase discretization result; The metasurface unit structure library corresponds to the emission spectrum range of the light-emitting pixel and includes multiple metasurface unit structures. Each metasurface unit structure corresponds to a phase value in the range of 0 to 2π, and the phase values ​​corresponding to each metasurface unit structure are different. The metasurface unit array is arranged according to the phase discretization results to construct the metasurface structure layer.

7. The method for manufacturing a display panel according to claim 5, characterized in that, The formation of the metasurface structure layer includes the following steps: A metasurface film and a hard mask layer are sequentially deposited on the light-emitting surface of the substrate; Patterning and etching are performed sequentially on the hard mask layer to transfer the pattern on the hard mask layer onto the metasurface film layer; Remove the hard mask layer to form the metasurface structure layer; The metasurface structure layer includes multiple metasurface units that match the wavelengths of the RGB primary color light.

8. An application of a display panel, characterized in that, The display panel described in any one of claims 1-4 is applied to naked-eye 3D light field display; or, the display panel prepared by any one of the preparation methods in claims 5-7 is applied to naked-eye 3D light field display.

9. An AR near-eye display device, characterized in that, include: Optical waveguides have both coupling-in and coupling-out structures; The display panel as described in any one of claims 1 to 4 or the display panel prepared by any one of claims 5 to 7, wherein the display panel serves as a light source device and is disposed on one side of the coupling structure of the optical waveguide, and the light emitted by the display panel enters the optical waveguide through the coupling structure and propagates to the coupling structure and exits.

10. The AR near-eye display device according to claim 9, characterized in that, The coupling structure includes a geometric coupling device, wherein the metasurface structure layer is spaced apart from the geometric coupling device or the metasurface structure layer is attached to the mirror surface of the geometric coupling device.

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