Optical waveguide, display apparatus, and near-eye display device

Abstract

An optical waveguide, comprising: a waveguide substrate; and an in-coupling region, an out-coupling region, and a metasurface structure which are disposed on the waveguide substrate, wherein the metasurface structure is disposed between an image source screen and the in-coupling region. The metasurface structure is configured to collimate incident light provided by the image source screen to obtain collimated incident light; the in-coupling region is configured to couple the collimated incident light into the waveguide substrate; and the out-coupling region is configured to couple the incident light propagating in the waveguide substrate out to human eyes.

Description

Optical waveguides, display devices and near-eye display equipment

[0001] This application claims priority to Chinese Patent Application No. 2024119131893, filed on December 23, 2024, entitled "Optical Waveguide, Display Device and Near-Eye Display Device", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of near-eye display technology, and more particularly to an optical waveguide, display device, and near-eye display equipment. Background Technology

[0003] In related technologies, the display device of a near-eye display generally includes an image source screen, a projection collimating lens, and a pupil-expanding waveguide. Because the projection collimating lens involves many optical components, its size is often relatively large. During the manufacturing of the near-eye display device, the projection collimating lens, image source screen, and pupil-expanding waveguide require precise assembly. A large projection collimating lens consequently increases the size of the near-eye display device, which can negatively impact its miniaturization. Summary of the Invention

[0004] The main objective of this application is to provide an optical waveguide, a display device, and a near-eye display device, aiming to solve the technical problem that the large size of the display device in the near-eye display device is due to the large size of the projection collimating lens, which in turn has an adverse effect on the miniaturization of the near-eye display device.

[0005] In a first aspect, this application provides an optical waveguide, comprising:

[0006] Waveguide substrate:

[0007] A coupling-in region, a coupling-out region, and a metasurface structure are disposed on the waveguide substrate; the metasurface structure is disposed between the image source screen and the coupling-in region.

[0008] The metasurface structure is used to collimate the incident light provided by the image source screen to obtain collimated incident light; the coupling region is used to couple the collimated incident light into the waveguide substrate; and the coupling region is used to couple the incident light propagating in the waveguide substrate out to the human eye.

[0009] Secondly, this application also provides a display device, comprising:

[0010] As mentioned above, optical waveguides;

[0011] An image source screen is positioned close to the metasurface structure of the optical waveguide relative to the coupling region of the optical waveguide; the image source screen is used to provide incident light to the optical waveguide.

[0012] Thirdly, this application also provides a near-eye display device, including: the display device as described above.

[0013] This application provides an optical waveguide, a display device, and a near-eye display device. The optical waveguide includes: a waveguide substrate; a coupling-in region, a coupling-out region, and a metasurface structure disposed on the waveguide substrate; the metasurface structure is disposed between an image source screen and the coupling-in region; wherein, the metasurface structure is used to collimate the incident light provided by the image source screen to obtain collimated incident light; the coupling-in region is used to couple the collimated incident light into the waveguide substrate; and the coupling-out region is used to couple the incident light propagating in the waveguide substrate out to the human eye.

[0014] When a metasurface structure is placed on the waveguide substrate of an optical waveguide, the metasurface structure can collimate the incident light from the image source screen, effectively giving the metasurface structure the light processing capabilities of a projection system, such as a projection collimating lens. Furthermore, the optical waveguide itself can possess its own waveguide system, such as a pupil-expanding waveguide sheet, allowing for the integrated placement of both the projection system and the waveguide system. Consequently, due to the smaller size of the metasurface structure, placing a metasurface structure with light processing capabilities corresponding to a projection system on the optical waveguide helps reduce the size of the integrated projection system and waveguide system, thus promoting miniaturization. Moreover, since the optical waveguide can be placed in both the display device and the near-eye display device, with the waveguide possessing the respective light processing capabilities of both the projection system and the waveguide system, there is no need to place a projection system within the display device or near-eye display device. This further reduces the size of both the display device and the near-eye display device, facilitating miniaturization of both. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 is a schematic diagram of the projection collimating lens involved in the related technology.

[0017] Figure 2 is a schematic diagram of an optical waveguide provided in an embodiment of this application;

[0018] Figure 3 is a schematic diagram of the structure of an optical waveguide according to an embodiment of this application;

[0019] Figure 4 is a schematic diagram of the structure of an optical waveguide according to another embodiment of this application;

[0020] Figure 5 is a schematic diagram of the structure of a display device provided in an embodiment of this application;

[0021] Figure 6 is a manufacturing process diagram of a display device according to an embodiment of this application;

[0022] Figure 7 is a manufacturing process diagram of the display device involved in the related technology;

[0023] Figure 8 is a structural schematic diagram of a near-eye display device provided in an embodiment of this application;

[0024] Figures 9a and 9b are schematic diagrams of the structure of a near-eye display device provided in an embodiment of this application.

[0025] Explanation of reference numerals in the attached figures: 10, near-eye display device; 100, display device; 110, optical waveguide; 111, waveguide substrate; 112, coupling region; 113, coupling out region; 114, metasurface structure; 120, image source screen; 200, device bracket. Detailed Implementation

[0026] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] The flowchart shown in the attached diagram is for illustrative purposes only and does not necessarily include all content and operations / steps, nor does it necessarily have to be performed in the order described. For example, some operations / steps can be broken down, combined, or partially merged, so the actual execution order may change depending on the actual situation.

[0028] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0029] In related technologies, the display device of a near-eye display device may include an image source screen, a projection collimating lens, and a pupil-expanding waveguide. The projection collimating lens is equivalent to the projection system in the near-eye display device and / or the display device of the near-eye display device, and the pupil-expanding waveguide is equivalent to the optical waveguide system in the near-eye display device and / or the display device of the near-eye display device. For example, incident light from the image source screen is collimated by the projection collimating lens, coupled into the pupil-expanding waveguide, and then transmitted through the pupil-expanding waveguide before entering the human eye. As shown in Figure 1, the projection collimating lens is generally obtained by precisely assembling multiple lenses, which tends to result in a large size. For example, the projection collimating lens is manufactured by performing glass cold processing, molding glass, or injection molding of multiple lenses. With a large projection collimating lens, the display device is correspondingly larger, which is detrimental to improving the manufacturing convenience of miniaturized near-eye display devices.

[0030] Please refer to Figure 2, which is a schematic diagram of the structure of an optical waveguide 110 provided in an embodiment of this application. The optical waveguide 110 can be disposed in a display device 100, and the display device 100 can be disposed in a near-eye display device 10 to realize the display capabilities of the display device 100 and the near-eye display device 10. The near-eye display device 10 may include augmented reality (AR) glasses, virtual reality (VR) glasses, mixed reality (MR) glasses, AR helmets, VR helmets, MR helmets, etc., and is not limited thereto.

[0031] As shown in Figure 2, the optical waveguide 110 includes a waveguide substrate 111; a coupling region 112, a coupling region 113, and a metasurface structure 114 disposed on the waveguide substrate 111; the metasurface structure 114 is disposed between the image source screen 120 and the coupling region 112; wherein, the metasurface structure 114 is used to collimate the incident light provided by the image source screen 120 to obtain collimated incident light; the coupling region 112 is used to couple the collimated incident light into the waveguide substrate 111; the coupling region 113 is used to couple the incident light propagating in the waveguide substrate 111 out to the human eye.

[0032] The image source screen 120 can provide incident light to the optical waveguide 110. The incident light can illuminate the metasurface structure 114 disposed on the waveguide substrate 111 of the optical waveguide 110. The metasurface structure 114 can collimate the incident light to obtain collimated incident light. Since the metasurface structure 114 is disposed close to the coupling region 112, the collimated incident light can illuminate the coupling region 112 and be coupled into the waveguide substrate 111 after being acted upon by the coupling region 112. Under the condition that the collimated incident light meets the preset total internal reflection propagation conditions, the collimated incident light can propagate through total internal reflection inside the waveguide substrate 111 to the coupling region 113, and then be coupled out to the human eye through the coupling region 113. Accordingly, since the incident light provided by the image source screen 120 can correspond to the image provided by the image source screen 120, when the incident light transmitted from the waveguide substrate 111 is coupled out to the human eye in the coupling region 113 of the optical waveguide 110, the user can view the image provided by the image source screen 120. Based on this, the optical waveguide 110 can have display capabilities. Accordingly, the optical waveguide 110 can have the light processing capabilities corresponding to the optical waveguide system included in the near-eye display device and / or display device in the related art, and the metasurface structure 114 provided on the optical waveguide 110 can have the processing capabilities corresponding to the projection system included in the near-eye display device and / or display device in the related art. Therefore, the setting of the optical waveguide 110 can realize the integrated setting of the projection system and the optical waveguide system.

[0033] For example, metasurface structure 114 can be used to indicate a two-dimensional planar lens structure. Metasurface structure 114 can include periodic or quasi-periodic subwavelength unit structures. The unit structures included in metasurface structure 114 can have micrometer or nanometer dimensions, thus the size of metasurface structure 114 is correspondingly small. Metasurface structure 114 can be used to manipulate properties of light such as polarization, phase, and amplitude.

[0034] In one exemplary embodiment, the metasurface structure 114 is constructed from a planar two-dimensional (2D) metamaterial having a subwavelength thickness. Metamaterials are used to indicate materials with special physical properties. Metamaterials possess properties superior to conventional materials, and the transmission and reflection characteristics of light can be modulated by designing the microstructure of the metamaterial. For example, when designing the metasurface structure 114, the metamaterial can be fabricated into a two-dimensional planar structure with extremely small thickness to form the metasurface structure 114.

[0035] Since the metasurface structure 114 has the ability to control the polarization, phase, amplitude and other properties of light, the metasurface structure 114 of the optical waveguide 110 has the ability to collimate the incident light provided by the image source screen 120.

[0036] For example, the phase distribution of the metasurface structure 114 can be designed so that the optical waveguide 110 can use the metasurface structure 114 to collimate the incident light provided by the image source screen 120.

[0037] In some embodiments, the phase distribution of the metasurface structure 114 satisfies:

[0038]

[0039] Wherein, λ is used to indicate the wavelength of the incident light illuminating the metasurface structure 114, f is used to indicate the focal length of the metasurface structure 114, and x and y are used to indicate the spatial coordinates of the center point of the metasurface structure 114.

[0040] The phase distribution of metasurface structure 114 satisfies In this case, the optical waveguide 110 can use the metasurface structure 114 to perform phase modulation on the incident light provided by the image source screen 120, so as to focus the incident light by changing the shape of the wavefront of the incident light, thereby achieving collimation processing of the incident light.

[0041] In some embodiments, the metasurface structure 114 includes a metasurface or a metalens.

[0042] For example, metasurfaces can be used to indicate an artificial layered material with a thickness less than the wavelength. Metasurfaces enable flexible and effective control over the polarization, amplitude, phase, polarization, and propagation mode of electromagnetic waves. Based on their internal structure, metasurfaces can be categorized into microstructures with transverse subwavelengths and uniform films. Based on the type of wave being controlled, metasurfaces can be classified as optical metasurfaces, acoustic metasurfaces, and mechanical metasurfaces. Taking optical metasurfaces as an example, they can control the polarization, phase, amplitude, and frequency of electromagnetic waves through subwavelength microstructures, such as adjusting the polarization, phase, and amplitude of incident light provided by the image source screen 120.

[0043] For example, a superlens, also known as a meta-lens, is a planar lens with focusing capabilities. A superlens can be made from an optical element that focuses light using a metasurface, possessing focusing capabilities exceeding the diffraction limit and the ability to capture light signals. Superlenses utilize metasurfaces to focus light, with the metasurface being a key component. Superlenses offer advantages such as thinner size, lighter weight, lower cost, better imaging, and easier integration, providing a potential solution for compact, integrated metasurface structures 114. Furthermore, the polarization, phase, and amplitude of light can be controlled by adjusting parameters such as the structure's shape, rotation direction, and height, for example, controlling the polarization, phase, and amplitude of the incident light provided by the image source screen 120. Superlenses can be used to overcome the diffraction limit limitation of ordinary lenses, focusing light into a tiny point.

[0044] When the optical waveguide 110 is provided with a metasurface structure 114, the optical waveguide 110 can utilize the ability of the metasurface structure 114, such as a metasurface or a metalens, to control the polarization, phase, amplitude, and other properties of light, thereby achieving collimation processing of the incident light provided by the image source screen 120. Correspondingly, since the size of the metasurface structure 114, such as a metasurface or a metalens, is relatively small, it is beneficial to reduce the volume of the optical waveguide 110, thereby promoting the miniaturization of the optical waveguide 110.

[0045] Thus, based on the metasurface structure 114 in the optical waveguide 110, the optical waveguide 110 can collimate the incident light provided by the image source screen 120, obtaining collimated incident light. The collimated incident light can be coupled out to the human eye through the coupling region 112 and the coupling region 113 in sequence, thus enabling the optical waveguide 110 to display the image provided by the image source screen 120. Based on this, the optical waveguide 110 can achieve an integrated setup of the projection system and the optical waveguide system. With a small volume of metasurface structure 114, it is beneficial to reduce the volume of the optical waveguide 110, thereby facilitating the miniaturization of the optical waveguide 110.

[0046] For example, when a coupling region 112, a coupling region 113, and a metasurface structure 114 are provided on the waveguide substrate 111 of the optical waveguide 110, the placement positions of the coupling region 112, the coupling region 113, and the metasurface structure 114 on the waveguide substrate 111 can be designed.

[0047] In some embodiments, the waveguide substrate 111 includes opposing first and second sides; the first and second sides are used to provide at least one of coupling in region 112, coupling out region 113, and metasurface structure 114.

[0048] For example, when the coupling region 112, the coupling region 113, and the metasurface structure 114 all have certain dimensions, in order to ensure that the first and second sides of the waveguide substrate 111 can be used to set at least one of the coupling region 112, the coupling region 113, and the metasurface structure 114, and to ensure the display capability of the optical waveguide 110, the first and second sides of the waveguide substrate 111 can be the two longer sides of the waveguide substrate 111. Correspondingly, the other sides of the waveguide substrate 111 besides the first and second sides can be the shorter sides of the waveguide substrate 111.

[0049] In one exemplary embodiment, one side of the waveguide substrate 111 can be designated as the first side, and the side of the waveguide substrate 111 opposite to the first side can be designated as the second side. Referring to FIG2, when the first side of the waveguide substrate 111 is located on the upper side of the waveguide substrate 111, the second side of the waveguide substrate 111 can be located on the lower side of the waveguide substrate 111. However, this is not a limitation; when the first side of the waveguide substrate 111 is located on the lower side of the waveguide substrate 111, the second side of the waveguide substrate 111 can be located on the upper side of the waveguide substrate 111. The first and second sides of the waveguide substrate 111 can be pre-defined or user-defined, and are not limited here.

[0050] When a coupling region 112, a coupling region 113, and a metasurface structure 114 are provided on a waveguide substrate 111, the coupling region 112, the coupling region 113, and the metasurface structure 114 can be provided on at least one of the first side surface and the second side surface.

[0051] In some embodiments, the metasurface structure 114 is disposed on one of the first side surface and the second side surface, the coupling-in region 112 and the coupling-out region 113 are disposed on the other of the first side surface and the second side surface, and the coupling-in region 112 is a first reflective optical structure.

[0052] As shown in Figure 3, the metasurface structure 114 can be located on different sides of the waveguide substrate 111, along with the coupling-in region 112 and the coupling-out region 113. For example, the metasurface structure 114 can be disposed on one of the first side and the second side, while the coupling-in region 112 and the coupling-out region 113 can be disposed on the other of the first side and the second side. The coupling-in region 112 is a first reflective optical structure. When the metasurface structure 114 is disposed between the image source screen 120 and the coupling-in region 112, the metasurface structure 114 can collimate the incident light provided by the image source screen 120 before propagating it to the coupling-in region 112. Correspondingly, the coupling-in region 112 can use the light reflection capability of the first reflective optical structure to couple the collimated incident light into the waveguide substrate 111, thereby propagating it through the waveguide substrate 111 to the coupling-out region 113, which is located on a different side from the metasurface structure 114.

[0053] In some embodiments, the metasurface structure 114 and the coupling region 113 are disposed on one of the first side surface and the second side surface, and the coupling region 112 is disposed on the other of the first side surface and the second side surface, and the coupling region 112 is a first reflective optical structure.

[0054] As shown in Figure 2, the metasurface structure 114 can be located on the same side of the waveguide substrate 111 as the coupling-out region 113, and on a different side of the waveguide substrate 111 as the coupling-in region 112. The metasurface structure 114 and the coupling-out region 113 can be disposed on one of the first side or the second side, and the coupling-in region 112 can be disposed on the other of the first side or the second side. The coupling-in region 112 is a first reflective optical structure. When the metasurface structure 114 is disposed between the image source screen 120 and the coupling-in region 112, the metasurface structure 114 can collimate the incident light provided by the image source screen 120 before propagating it to the coupling-in region 112. Correspondingly, the coupling-in region 112, through the light reflection capability of the first reflective optical structure, couples the collimated incident light into the waveguide substrate 111, thereby propagating through the waveguide substrate 111 to the coupling-out region 113 located on the same side as the metasurface structure 114.

[0055] In one exemplary embodiment, when the metasurface structure 114 and the coupling region 112 are disposed on different sides, the coupling region 112 may be a first reflective optical structure. The first reflective optical structure may include a reflective grating, but is not limited thereto, and is not restricted herein.

[0056] In some embodiments, the metasurface structure 114 is disposed on one of the first side surface and the second side surface, the coupling-in region 112 and the coupling-out region 113 are disposed between the first side surface and the second side surface, and the setting direction of the coupling-in region 112 is different from that of the coupling-out region 113, and the coupling-in region 112 is a second reflective optical structure.

[0057] As shown in Figure 4, the metasurface structure 114 can be disposed on one of the first side surface and the second side surface. The coupling-in region 112 and the coupling-out region 113 can be disposed between the first side surface and the second side surface, and the orientation of the coupling-in region 112 is different from that of the coupling-out region 113. The coupling-in region 112 is a second reflective optical structure. When the metasurface structure 114 is disposed between the image source screen 120 and the coupling-in region 112, the metasurface structure 114 can collimate the incident light provided by the image source screen 120 before propagating it to the coupling-in region 112. Correspondingly, the coupling-in region 112 can use the light reflection capability of the second reflective optical structure to couple the collimated incident light into the waveguide substrate 111, thereby propagating through the waveguide substrate 111 to the coupling-out region 113 located between the first side surface and the second side surface.

[0058] In an exemplary embodiment, where the coupling-in region 112 and the coupling-out region 113 are disposed between the first and second sides of the waveguide substrate 111, the optical waveguide 110 may include a geometrical waveguide 110, and the coupling-in region 112 may be a second reflective optical structure. The second reflective optical structure may include a coupling-in reflective surface. Correspondingly, the coupling-out region 113 may include at least one selectively coupling-out reflective surface. The incident light provided by the image source screen 120, after being collimated by the metasurface structure 114, can illuminate the coupling-in reflective surface. After being coupled into the interior of the waveguide substrate 111 via the coupling-in reflective surface and propagated through total internal reflection to at least one selectively coupling-out reflective surface, it is coupled out of the waveguide substrate 111 via at least one selectively coupling-out reflective surface, and then coupled out to the human eye. Of course, this is not a limitation and is not intended to restrict the application of this method.

[0059] Based on this, when setting the coupling region 112, the coupling region 113, and the metasurface structure 114 on the waveguide substrate 111, different methods can be used, which is beneficial to improving the design flexibility of the optical waveguide 110.

[0060] For example, the metasurface structure 114, the coupling region 112, and the coupling region 113 are disposed on the waveguide substrate 111 using a preset processing technology.

[0061] For example, in the process of setting the metasurface structure 114, the coupling region 112 and the coupling region 113 on the waveguide substrate 111 of the optical waveguide 110, the same preset processing technology can be used to process the metasurface structure 114, the coupling region 112 and the coupling region 113 to simplify the processing flow of the optical waveguide 110 and thus improve the manufacturing efficiency of the optical waveguide 110.

[0062] In some embodiments, the preset processing technology includes at least one of double-sided etching, double-sided imprinting, and single-sided etching and single-sided imprinting.

[0063] Since the metasurface structure 114 is small in size, and the coupling region 112 and the coupling region 113 are also small in size, when the metasurface structure 114, the coupling region 112 and the coupling region 113 are disposed on the waveguide substrate 111, at least one of the following processes can be used: double-sided etching process, double-sided imprinting process, and single-sided etching and single-sided imprinting process.

[0064] For example, at least one of the following can be used: double-sided etching process, double-sided imprinting process, and single-sided etching and single-sided imprinting process, to form at least one of the following on the first and second sides of the waveguide substrate 111: coupling region 112, coupling region 113, and metasurface structure 114. Of course, the preset processing technology is not limited to this, and is not restricted here.

[0065] Thus, by pre-setting the processing technology, the metasurface structure 114, the coupling region 112 and the coupling region 113 can be set on the waveguide substrate 111 of the optical waveguide 110, which helps to simplify the manufacturing process of the optical waveguide 110 and improve the manufacturing efficiency of the optical waveguide 110.

[0066] The optical waveguide 110 provided in this embodiment includes: a waveguide substrate 111; a coupling region 112, a coupling region 113, and a metasurface structure 114 disposed on the waveguide substrate 111; the metasurface structure 114 is disposed between the image source screen 120 and the coupling region 112; wherein, the metasurface structure 114 is used to collimate the incident light provided by the image source screen 120 to obtain collimated incident light; the coupling region 112 is used to couple the collimated incident light into the waveguide substrate 111; the coupling region 113 is used to couple the incident light propagating in the waveguide substrate 111 out to the human eye.

[0067] When a metasurface structure 114 is provided on the waveguide substrate 111 of the optical waveguide 110, the metasurface structure 114 can collimate the incident light provided by the image source screen 120. This is equivalent to the metasurface structure 114 possessing the light processing capabilities of a projection system, such as a projection collimating lens. Furthermore, the optical waveguide 110 itself can possess the light processing capabilities of an optical waveguide system, such as a pupil-expanding optical waveguide sheet. Therefore, a projection system and an optical waveguide system can be integrated on the optical waveguide 110. Correspondingly, since the metasurface structure 114 is relatively small, providing a metasurface structure 114 with light processing capabilities corresponding to a projection system on the optical waveguide 110 helps reduce the volume of the integrated projection system and optical waveguide system, thereby promoting the miniaturization of the integrated projection system and optical waveguide system. Furthermore, the optical waveguide 110 can be disposed on the display device 100 and the near-eye display device 10. When the optical waveguide 110 has the light processing capabilities corresponding to the projection system and the optical waveguide system, there is no need to set up a projection system in the display device 100 and the near-eye display device 10. This is beneficial to reduce the size of the display device 100 and the near-eye display device 10, thereby promoting the miniaturization of the display device 100 and the near-eye display device 10.

[0068] Please refer to Figure 5, which is a schematic diagram of the structure of a display device 100 provided in an embodiment of this application.

[0069] As shown in FIG5, the display device 100 includes the aforementioned optical waveguide 110; an image source screen 120, which is disposed close to the metasurface structure 114 of the optical waveguide 110 relative to the coupling region 112 of the optical waveguide 110; the image source screen 120 is used to provide incident light to the optical waveguide 110.

[0070] When the image source screen 120 of the display device 100 provides incident light to the optical waveguide 110 of the display device 100, since the image source screen 120 is located closer to the metasurface structure 114 of the optical waveguide 110 than the coupling region 112 of the optical waveguide 110, the incident light can preferentially illuminate the metasurface structure 114. When incident light illuminates the metasurface structure 114 of the optical waveguide 110, the metasurface structure 114 can collimate the incident light to obtain collimated incident light. Accordingly, the collimated incident light can propagate to the coupling region 112 of the optical waveguide 110, and after being coupled into the waveguide substrate 111 through the coupling region 112, it propagates inside the waveguide substrate 111 to the coupling region 113 and then exits to the human eye. Since the incident light provided by the image source screen 120 corresponds to the image provided by the image source screen 120, when the corresponding incident light is coupled out to the human eye by the coupling region 113, the user can view the image corresponding to the incident light, thus realizing the display capability of the display device 100. Based on the setting of the metasurface structure 114 in the optical waveguide 110, the optical waveguide 110 can have the light processing capabilities corresponding to both the projection system and the optical waveguide system. When the optical waveguide 110 is set in the display device 100, the projection system and the optical waveguide system can be integrated into the display device 100, which is conducive to promoting the miniaturization of the integrated projection system and the optical waveguide system. Furthermore, since the coupling region 112, the coupling region 113, and the metasurface structure 114 set on the waveguide substrate 111 of the optical waveguide 110 are all small in size, it is beneficial to reduce the volume of the optical waveguide 110, thereby reducing the volume of the display device 100, which in turn improves the ease of manufacturing the miniaturized display device 100. The specific principle and implementation of the optical waveguide 110 can be referred to the optical waveguide 110 in the aforementioned embodiment, and will not be repeated here.

[0071] In some embodiments, as shown in FIG6, the manufacturing process of the display device 100 may include the manufacturing process of the optical waveguide 110 and the assembly process between the optical waveguide 110 and the image display screen. The manufacturing process of the optical waveguide 110 may include optical waveguide 110 design, template processing corresponding to the optical waveguide 110, optical waveguide 110 production, and optical waveguide 110 performance testing. Specifically, the optical waveguide 110 design includes, for example, designing at least one of the positions, quantities, and component types of the coupling region 112, coupling region 113, and metasurface structure 114 disposed on the waveguide substrate 111. Template processing corresponding to the optical waveguide 110 includes, for example, producing molds required for processing the optical waveguide 110 according to a preset processing technology, for subsequent mass production of the same type of optical waveguide 110. Optical waveguide 110 production includes, for example, producing the optical waveguide 110 according to the molds corresponding to the optical waveguide 110. During the production of the optical waveguide 110, at least one of the following preset processing techniques can be used: double-sided etching, double-sided imprinting, or single-sided etching and single-sided imprinting. No limitation is imposed here. Performance testing of the optical waveguide 110 includes, for example, testing whether the optical waveguide 110 possesses collimation capability, coupling capability, and coupling capability for incident light, to determine whether the optical waveguide 110 has display capability. If it is determined that the optical waveguide 110 has display capability, the optical waveguide 110 and the image source screen 120 can be assembled to obtain the corresponding display device 100. The display device 100 also correspondingly possesses the capability to display the image provided by the image source screen 120.

[0072] In related technologies, a display device may include an image source screen, a projection collimating lens, and a pupil-expanding waveguide. As shown in Figure 7, the manufacturing process of the display device involved in the related technologies includes the lens manufacturing process, the lens-image source screen corresponding projection optical engine assembly process, the waveguide manufacturing process, and the optical engine-waveguide corresponding display device assembly process. The lens manufacturing process includes lens design, multi-lens structure design, lens mold design, lens assembly, and lens testing. The waveguide manufacturing process includes waveguide design, waveguide template processing, waveguide production, and waveguide testing. Accordingly, after manufacturing the projection collimating lens, it needs to be assembled with the image source screen into a projection optical engine using precision machining processes, such as high-precision AA (Advanced Aspect Ratio) technology. Furthermore, the projection optical engine needs to be precisely assembled with the pupil-expanding waveguide to obtain the corresponding display device, enabling the display device to have display capabilities. The manufacturing process of the display device designed in the related technologies is complex and time-consuming, and the large size of the projection collimating lens easily leads to a correspondingly large display device size.

[0073] Compared to the manufacturing process of display devices in related technologies, this application simplifies the projection collimating lens into a metasurface structure 114 disposed on the waveguide substrate 111 of the optical waveguide 110. This allows for the integrated placement of the projection system and the optical waveguide system on the optical waveguide 110, thus simplifying the manufacturing process of the optical waveguide 110 and reducing its size. Correspondingly, this also simplifies the manufacturing process of the display device 100 and reduces its size. Therefore, the display device 100 of this application can be subsequently used to manufacture a near-eye display device 10, which simplifies the manufacturing process of the near-eye display device 10 and reduces its size.

[0074] The display device 100 provided in this application embodiment includes: the aforementioned optical waveguide 110; an image source screen 120, which is disposed close to the metasurface structure 114 of the optical waveguide 110 relative to the coupling region 112 of the optical waveguide 110; the image source screen 120 is used to provide incident light to the optical waveguide 110.

[0075] Since the image source screen 120 of the display device 100 is positioned close to the metasurface structure 114 of the optical waveguide 110 in the display device 100, when the image source screen 120 provides incident light to the optical waveguide 110, it can also provide incident light to the metasurface structure 114. Accordingly, the metasurface structure 114 can collimate the incident light and then propagate it to the coupling region 112 of the optical waveguide 110. After being coupled into the waveguide substrate 111 of the optical waveguide 110 through the coupling region 112, it propagates to the coupling region 113 of the optical waveguide 110 and is then coupled out to the human eye through the coupling region 113. Thus, the user can view the image corresponding to the incident light provided by the image source screen 120, thereby enabling the display device 100 to have display capabilities. Furthermore, the display device 100 can achieve integrated setup of the projection system and the optical waveguide system through the optical waveguide 110. Correspondingly, with a smaller size of the metasurface structure 114, it is advantageous to reduce the volume of the optical waveguide 110, thereby reducing the volume of the display device 100, which in turn facilitates the miniaturization of the display device 100.

[0076] Please refer to Figure 8, which is a structural schematic diagram of a near-eye display device 10 provided in an embodiment of this application.

[0077] As shown in Figure 8, the near-eye display device 10 includes the display device 100 as described above.

[0078] Since the display device 100 has display capabilities, when the display device 100 is provided in the near-eye display device 10, the near-eye display device 10 can also have display capabilities. Furthermore, the near-eye display device 10 can achieve integrated setup of the projection system and the optical waveguide system through the optical waveguide 110 in the display device 100. The specific principles and implementation methods of the display device 100 can be referred to in the aforementioned embodiment of the display device 100, and will not be repeated here.

[0079] In some embodiments, the display device 100 of the near-eye display device 10 can provide incident light to the optical waveguide 110 through the image source screen 120. The metasurface structure 114 provided on the waveguide substrate 111 of the optical waveguide 110 can collimate the incident light to obtain collimated incident light. The collimated incident light can illuminate the coupling region 112 on the waveguide substrate 111, and be coupled into the interior of the waveguide substrate 111 through the coupling region 112. After propagating inside the waveguide substrate 111 to the coupling region 113, it is coupled out through the coupling region 113 to the eye of the user wearing the near-eye display device 10. Since the incident light provided by the image source screen 120 corresponds to the image provided by the image source screen 120, when the corresponding incident light is coupled out through the coupling region 113 to the eye, the near-eye display device 10 can have near-eye display capability.

[0080] The near-eye display device 10 may include more devices besides the display device 100, such as eye-tracking devices, gesture recognition devices, voice recognition devices, etc., without limitation.

[0081] In some embodiments, the near-eye display device 10 further includes a device bracket 200, which is positioned close to the image source screen 120 of the display device 100 relative to the optical waveguide 110 in the display device 100.

[0082] For example, since users need to wear the near-eye display device 10 in front of their eyes, the near-eye display device 10 needs to be wearable. Based on this, the near-eye display device 10 can be provided with a device bracket 200, so that the near-eye display device 10 can be worn in front of the user's eyes through the support function of the device bracket 200.

[0083] As shown in Figures 9a and 9b, the image source screen 120 can be disposed between the device bracket 200 and the optical waveguide 110, so that the device bracket 200 can enable the near-eye display device 10 to be wearable without blocking the incident light provided by the image source screen 120 to the optical waveguide 110 of the display device 100. Accordingly, when the image source screen 120 is disposed between the device bracket 200 and the optical waveguide 110, the device bracket 200 and the display device 100 can also be compactly arranged. If the device bracket 200, the image source screen 120, and the optical waveguide 110 can be compactly arranged, it is beneficial to reduce the size of the near-eye display device 10, thereby promoting the miniaturization of the near-eye display device 10.

[0084] The near-eye display device 10 provided in this application embodiment includes the aforementioned display device 100.

[0085] Since the display device 100 has display capabilities, the near-eye display device 10, when equipped with the display device 100, can also have display capabilities. Furthermore, the near-eye display device 10 can achieve integrated setup of the projection system and the optical waveguide system through the optical waveguide 110 within the display device 100. Correspondingly, with a smaller display device 100, it is advantageous to reduce the size of the near-eye display device 10, thereby facilitating the miniaturization process of the near-eye display device 10.

[0086] It should be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0087] It should also be understood that the term "and / or" as used in this specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations. It should be noted that, herein, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0088] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. The above descriptions are merely specific implementations of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An optical waveguide, comprising: Waveguide substrate: A coupling-in region, a coupling-out region, and a metasurface structure are disposed on the waveguide substrate; the metasurface structure is disposed between the image source screen and the coupling-in region. The metasurface structure is used to collimate the incident light provided by the image source screen to obtain collimated incident light; the coupling region is used to couple the collimated incident light into the waveguide substrate; and the coupling region is used to couple the incident light propagating in the waveguide substrate out to the human eye.

2. The optical waveguide of claim 1, wherein, The waveguide substrate includes a first side surface and a second side surface opposite to each other; The first side and the second side are used to provide at least one of the coupling-in region, the coupling-out region, and the metasurface structure.

3. The optical waveguide of claim 2, wherein, The metasurface structure is disposed on one of the first side surface and the second side surface, and the coupling-in region and the coupling-out region are disposed on the other of the first side surface and the second side surface, wherein the coupling-in region is a first reflective optical structure; and / or, The metasurface structure and the coupling-out region are disposed on one of the first side surface and the second side surface, and the coupling-in region is disposed on the other of the first side surface and the second side surface, wherein the coupling-in region is a first reflective optical structure; and / or, The metasurface structure is disposed on one of the first side surface and the second side surface. The coupling-in region and the coupling-out region are disposed between the first side surface and the second side surface. The setting direction of the coupling-in region is different from that of the coupling-out region, and the coupling-in region is a second reflective optical structure.

4. The optical waveguide of claim 1, wherein, The phase distribution of the metasurface structure satisfies: Wherein, λ is used to indicate the wavelength of the incident light illuminating the metasurface structure, f is used to indicate the focal length of the metasurface structure, and x and y are used to indicate the spatial coordinates of the center point of the metasurface structure.

5. The optical waveguide of claim 1, wherein, The metasurface structure includes a metasurface or a metalens.

6. The optical waveguide of claim 1, wherein, The metasurface structure, the coupling region, and the coupling-out region are fabricated on the waveguide substrate using a pre-defined processing technique.

7. The optical waveguide of claim 6, wherein, The preset processing technology includes at least one of double-sided etching, double-sided imprinting, and single-sided etching and single-sided imprinting.

8. A display device, comprising: Optical waveguide as described in any one of claims 1 to 7; An image source screen is positioned close to the metasurface structure of the optical waveguide relative to the coupling region of the optical waveguide; the image source screen is used to provide incident light to the optical waveguide.

9. A near-eye display device, comprising the display device as described in claim 8.

10. The near-eye display device of claim 9, wherein, The near-eye display device also includes a device bracket, which is positioned close to the image source screen of the display device relative to the optical waveguide in the display device.

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