Optical waveguide assembly, near-eye display device and optical device

Abstract

The utility model discloses an optical waveguide assembly, a near-to-eye display device and an optical device, the optical waveguide assembly comprises a composite layer, a grating and a reflecting layer, the composite layer comprises a plurality of dielectric layers, the dielectric layers comprise a first dielectric layer located on the surface layer, and a total reflection area is at least formed in the first dielectric layer; the gratings are arranged on the same side of the first dielectric layer, the coupling-in grating is used for coupling incoming light into the total reflection area to form total reflection propagation, and the coupling-out grating is used for coupling at least one part of the light in the total reflection area out of the composite layer; the reflecting layers are selectively arranged in a plurality of areas on the outer side surface of the first dielectric layer and used for reflecting light rays of the total reflection area so that the light rays can continue to be transmitted along a total reflection path, and the reflecting layers of at least one area are arranged at intervals. According to the optical waveguide assembly disclosed by the utility model, external light can be transmitted to the composite layer on the premise that light can be propagated in a total reflection manner through the reflecting layers arranged at intervals, so that the lighting effect and the contrast display effect are ensured.

Description

Technical Field

[0001] This utility model relates to the field of optical device technology, and in particular to optical waveguide components, near-eye display devices, and optical devices. Background Technology

[0002] Optical waveguides are widely used in near-eye display devices such as augmented reality and mixed reality due to their thinness, light weight, and good light transmittance.

[0003] In existing optical waveguide products, the light in the total internal reflection region of the waveguide structure is easily affected by changes in the surface condition during propagation, which can affect the light's ability to achieve total internal reflection along the normal path. For example, when the surface is contaminated, some light will be absorbed or scattered, preventing the light in the total internal reflection region from propagating along the predetermined path to the coupling grating and reaching the human eye. This results in reduced light efficiency and decreased display effects such as contrast in the optical waveguide structure, impacting the user experience. Utility Model Content

[0004] In view of this, the present invention proposes an optical waveguide component, a near-eye display device, and an optical device, aiming to achieve total reflection of light in the total reflection region of the optical waveguide component along a predetermined propagation path, thereby reducing or avoiding the impact of changes in the surface state of the optical waveguide component on light propagation.

[0005] The optical waveguide assembly of the first aspect of this utility model includes: a composite layer comprising multiple dielectric layers, the dielectric layers including a first dielectric layer located on the surface, and forming a total internal reflection region in at least the first dielectric layer; a grating disposed on the same side of the first dielectric layer, the grating including an input grating and an output grating, the input grating being used to couple light entering the composite layer into the total internal reflection region to form total internal reflection propagation, and the output grating being used to couple at least a portion of the light in the total internal reflection region out of the composite layer; and a reflective layer disposed on the outer surface of the first dielectric layer, and the reflective layer reflecting the light in the total internal reflection region so that the light continues to propagate along the total internal reflection path, the reflective layer being selectively disposed in multiple regions on the outer surface of the first dielectric layer, with the reflective layers in at least one region being spaced apart.

[0006] As can be seen from the above technical solution, the optical waveguide component proposed in the first aspect of this utility model, when light is incident into the composite layer, is coupled into the total reflection region by the coupling grating to form total reflection propagation. When the light passes through the first dielectric layer on the surface during the total reflection propagation, the reflective layer on the outer surface of the first dielectric layer reflects the light to the total reflection region, enabling the light to propagate along a preset total reflection path, reducing the impact of changes in the surface state of the outer surface of the first dielectric layer on the total reflection propagation of the light. The reflective layers spaced apart on the outer surface of the first dielectric layer can ensure that the light can achieve total reflection propagation without obstructing the transmission of external light to the composite layer, reducing or avoiding interference with the visible area of ​​the human eye, keeping the waveguide light efficiency of the entire optical waveguide component within a preset threshold, and ensuring the contrast display effect of the entire optical waveguide component, thereby improving the user experience.

[0007] In some possible embodiments of this utility model, the light passes through the coupling grating and is incident on the total internal reflection region of the first dielectric layer, the region on the outer surface of the first dielectric layer that the incident light reaches during the total internal reflection is a first region, and the reflective layer is disposed in a portion of the first region; and / or, the reflective layer is disposed in a second region of the first dielectric layer opposite to the coupling grating; and / or, the reflective layer is disposed in a third region of the first dielectric layer that is easily contaminated.

[0008] In some further embodiments of this utility model, the reflective layer is disposed in the first region, and the reflective layer is arranged in an array on the outer surface of the first medium layer in an extension direction parallel to the total reflection region; or, the light has a period when it propagates by total reflection in the total reflection region, the reflective layer is disposed in the first region, and a plurality of the reflective layers are evenly spaced on the first medium layer.

[0009] In some embodiments of this utility model, the same reflective layer is used to reflect light rays that pass through the outer surface of the first dielectric layer once during total reflection propagation in the total reflection region. The light rays are formed by total reflection of two light rays with the same incident angle and the greatest distance in the total reflection region. The reflective layer reflects the light rays back to the total reflection region. The minimum dimension of the reflective layer in the extension direction parallel to the total reflection region is greater than or equal to the displacement difference between the two light rays when they first propagate to the outer surface of the first dielectric layer.

[0010] In some embodiments of this utility model, the number of reflective layers disposed on the surface of the first dielectric layer closer to the coupling grating is greater than the number of reflective layers disposed on the surface closer to the coupling grating; or, the total area of ​​the cross-sections of the reflective layers disposed on the surface of the first dielectric layer closer to the coupling grating is greater than the total area of ​​the cross-sections of the reflective layers disposed on the surface closer to the coupling grating.

[0011] In some possible embodiments of this utility model, the displacement of the reflective layer on the outer surface of the first dielectric layer is positively correlated with the position of the incident point of the light in the total reflection region, positively correlated with the diffraction angle of the light in the total reflection region, positively correlated with the thickness of the total reflection region, and positively correlated with the number of times the light propagates in the total reflection region.

[0012] In some possible embodiments of this utility model, the reflective layer is disposed in the second region, the reflective layer is arranged in a ring on the outer surface of the first dielectric layer, or, with the geometric center of the coupling grating passing through the outer surface of the first dielectric layer as a reference, a plurality of reflective layers are arranged concentrically at intervals.

[0013] In some possible embodiments of this utility model, the dielectric layer further includes a second dielectric layer and a third dielectric layer, with opposite sides of the second dielectric layer respectively connected to the first dielectric layer and the third dielectric layer; when a total reflection region is formed only in the first dielectric layer, the reflective layer is disposed on the outer surface of the first dielectric layer away from the second dielectric layer; when total reflection regions are formed simultaneously in the first dielectric layer and the second dielectric layer, the reflective layer is disposed on the outer surface of the first dielectric layer away from the second dielectric layer; when total reflection regions are formed simultaneously in the first dielectric layer, the second dielectric layer, and the third dielectric layer, a portion of the reflective layer is disposed on the outer surface of the first dielectric layer away from the second dielectric layer; and a portion of the reflective layer is disposed on the surface of the third dielectric layer away from the second dielectric layer.

[0014] In some embodiments of this invention, the refractive index of the first dielectric layer is greater than that of the second dielectric layer, and the refractive index of the first dielectric layer is greater than that of air, thus forming the total internal reflection region in the first dielectric layer; or, the materials of the first dielectric layer and the second dielectric layer are different and their refractive indices are approximately the same, the refractive indices of the first dielectric layer and the second dielectric layer are greater than that of the third dielectric layer, and the refractive indices of the first dielectric layer and the second dielectric layer are greater than that of air, thus forming the total internal reflection region in the first dielectric layer and the second dielectric layer; or, the materials of the first dielectric layer, the second dielectric layer, and the third dielectric layer are different and their refractive indices are approximately the same, the refractive indices of the first dielectric layer, the second dielectric layer, and the third dielectric layer are greater than that of air, thus forming the total internal reflection region in the first dielectric layer, the second dielectric layer, and the third dielectric layer.

[0015] In some embodiments of this utility model, when the second medium layer is an air layer, the composite layer further includes an adhesive layer, which is connected to the edge region between the third medium layer and the first medium layer, and the reflective layer is disposed on the outer surface of the first medium layer away from the second medium layer.

[0016] In some possible embodiments of this invention, the reflective layer includes a metal reflective film or a multilayer dielectric reflective film.

[0017] In some further embodiments of this utility model, the reflective layer is a metal reflective film with a thickness ranging from 200 nm to 400 nm; or, the reflective layer is a multilayer dielectric reflective film with a thickness ranging from 300 nm to 400 nm.

[0018] The near-eye display device according to the second aspect of this utility model includes: an optomechanism for emitting signal light; and the optical waveguide assembly described in the foregoing embodiments, wherein the optomechanism is configured corresponding to the coupling grating.

[0019] As can be seen from the above technical solution, in the near-eye display device proposed in the second aspect of this utility model, the optical engine emits light towards the coupling grating, and the coupling grating couples the light into the total internal reflection area to form total internal reflection propagation. When the light passes through the first dielectric layer on the surface during the total internal reflection propagation, the reflective layer provided on the first dielectric layer reflects the light to the total internal reflection area, so that the light can propagate along the preset total internal reflection path, reducing the influence of changes in the surface state of the outer surface of the first dielectric layer on the total internal reflection propagation of the light. The reflective layers arranged at intervals on the outer surface of the first dielectric layer can ensure that the light can achieve total internal reflection propagation without obstructing the transmission of external light to the composite layer, reducing or avoiding interference with the visible area of ​​the human eye, making the entire near-eye display device clear in imaging, and achieving effects such as virtual and real combination and enhanced display, ensuring the overall display effect.

[0020] The optical device proposed in the third aspect of this utility model includes the optical waveguide components of the foregoing embodiments.

[0021] As can be seen from the above technical solutions, the optical device proposed in the third aspect of this utility model can achieve total internal reflection of light along a predetermined path by using the aforementioned optical waveguide component, thereby reducing or avoiding the influence of changes in the surface state of the outer surface of the first dielectric layer on the total internal reflection propagation of light, resulting in good imaging effect and improved user experience.

[0022] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit the disclosure of the embodiments of this utility model. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of an optical waveguide component proposed in some embodiments of the present invention, wherein a total reflection region is formed only in the first dielectric layer, and the reflective layer is disposed on the first region of the first dielectric layer, and the grating is a reflective grating;

[0025] Figure 2 This is a schematic diagram of the structure of an optical waveguide component proposed in some embodiments of the present invention, wherein a total reflection region is formed only in the first dielectric layer, and the reflective layer is disposed on the second region of the first dielectric layer, and the grating is a reflective grating;

[0026] Figure 3This is a schematic diagram of the structure of an optical waveguide component proposed in some embodiments of the present invention, wherein a total reflection region is formed only in the first dielectric layer, and the reflective layer is disposed on the third region of the first dielectric layer, and the grating is a reflective grating;

[0027] Figure 4 This is a schematic diagram of the structure of an optical waveguide component proposed in some embodiments of the present invention, wherein a total reflection region is formed only in the first dielectric layer, and the reflective layer is disposed on the second region of the first dielectric layer, and the grating is a transmission grating;

[0028] Figure 5 This is a schematic diagram of the structure of an optical waveguide component proposed in some embodiments of the present invention, wherein a total reflection region is formed in the first dielectric layer and the second dielectric layer, and the reflective layer is disposed on the outer surface of the first dielectric layer, and the grating is a reflective grating;

[0029] Figure 6 This is a schematic diagram of the structure of an optical waveguide component proposed in some embodiments of the present invention, wherein a total reflection region is formed in the first dielectric layer and the second dielectric layer, and the reflective layer is disposed on the outer surface of the first dielectric layer, and the grating is a transmission grating;

[0030] Figure 7 This is a schematic diagram of the structure of an optical waveguide component proposed in some embodiments of the present invention, wherein a total reflection region is formed in the first dielectric layer, the second dielectric layer and the third dielectric layer, and a reflective layer is disposed on the outer surface of the first dielectric layer and the surface of the third dielectric layer, and the grating is a reflective grating;

[0031] Figure 8 This is a schematic diagram of the structure of an optical waveguide component proposed in some embodiments of the present invention, wherein a total reflection region is formed in the first dielectric layer, the second dielectric layer and the third dielectric layer, and the reflective layer is disposed on the outer surface of the first dielectric layer and the surface of the third dielectric layer, and the grating is a transmission grating;

[0032] Figure 9 This is a schematic diagram of the structure in which the reflective layer is arranged in a ring on the outer surface of the first dielectric layer, according to some embodiments of this utility model;

[0033] Figure 10 This is a schematic diagram of the structure of multiple reflective layers arranged concentrically at intervals on the outer surface of the first dielectric layer, as proposed in some embodiments of this utility model.

[0034] Figure 11 This is a schematic diagram of the structure of an optical waveguide component proposed in some embodiments of the present invention, wherein the second dielectric layer is an air layer;

[0035] Figure 12 This is a three-dimensional structural schematic diagram of a near-eye display device proposed in some embodiments of this utility model.

[0036] Explanation of reference numerals in the attached figures:

[0037] 1000. Near-eye display device; 200. Optical mechanism; 300. Lens; 400. Frame; 500. Temples;

[0038] 100. Optical waveguide components;

[0039] 10. Composite layer;

[0040] 11. First dielectric layer; 110. Outer surface;

[0041] 111. First area; 112. Second area; 113. Third area;

[0042] 12. Second dielectric layer; 13. Third dielectric layer; 14. Adhesive layer;

[0043] 20. Grating; 21. Coupled-in grating; 22. Coupled-out grating;

[0044] 30. Reflective layer. Detailed Implementation

[0045] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are all within the protection scope of the present utility model.

[0046] It should also be understood that the terminology used in this application specification is for the purpose of describing particular embodiments only and is not intended to limit the application. As used in this application 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.

[0047] It should also be further understood that the term "and / or" as used in this application specification and the appended claims refers to any combination of one or more of the associated listed items, and all possible combinations thereof. Without conflict, the following embodiments and features described herein can be combined with each other.

[0048] In existing optical waveguide products, the light in the total reflection area of ​​the optical waveguide structure is easily affected by changes in the surface state during propagation, which can affect the light from achieving total reflection propagation along the normal path. This results in reduced light efficiency and decreased display effects such as contrast in the optical waveguide structure, thus affecting the user experience.

[0049] In view of this, the present invention proposes an optical waveguide component 100, such as... Figure 1, Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 11 As shown, it includes: a composite layer 10, a grating 20, and a reflective layer 30.

[0050] The composite layer 10 includes multiple dielectric layers, including a first dielectric layer 11 located on the surface. At least one total internal reflection region is formed within the first dielectric layer 11. These multiple dielectric layers can be stacked, i.e., arranged sequentially in a certain order. There will be two dielectric layers on the surface, including the first dielectric layer 11. A total internal reflection region can be formed in the first dielectric layer 11, allowing light to propagate through total internal reflection after reaching this region.

[0051] refer to Figures 1 to 8 , Figure 11 As shown, the grating 20 is disposed on the same side of the first dielectric layer 11. The grating 20 includes an input grating 21 and an output grating 22. The input grating 21 is used to couple the light entering the composite layer 10 into the total internal reflection region to form total internal reflection propagation. The output grating 22 is used to couple at least a portion of the light from the total internal reflection region out of the composite layer 10 and into the user's eye. The grating 20 of this application can be any desired structure, such as a transmission grating, a reflection grating, a surface relief grating, or a volume holographic grating, etc., without limitation.

[0052] The reflective layer 30 is disposed on the outer surface 110 of the first dielectric layer 11, and the reflective layer 30 enables light rays entering the first dielectric layer 11 to propagate along a total internal reflection path. Here, the outer surface 110 mainly refers to the side surface of the first dielectric layer 11 that is away from other dielectric layers. When light propagates in the total internal reflection area of ​​the first dielectric layer 11, it will pass through the aforementioned outer surface 110 of the first dielectric layer 11. Moreover, a large area of ​​the outer surface 110 of the first dielectric layer 11 is exposed to the external environment, making it easy to accumulate dust, fingerprints, or other contaminants.

[0053] The reflective layer 30 can be selectively disposed in multiple regions on the outer surface 110 of the first dielectric layer 11, with the reflective layer 30 spaced apart in at least one region. These multiple regions can be physically separated regions, functionally separated regions, or regions with different degrees of contamination.

[0054] As can be seen from the above, the optical waveguide component 100 proposed in this utility model has a large area of ​​the outer surface 110 of the first dielectric layer 11 exposed to the external environment. Therefore, the outer surface 110 is prone to contamination with a lot of dust, fingerprints, oil and other pollutants. These pollutants will change the refractive index of the outer surface 110 of the first dielectric layer 11, thereby changing the propagation path of the light entering the area of ​​the contaminated outer surface 110 of the first dielectric layer 11. That is, it is impossible to achieve total internal reflection propagation in the first dielectric layer 11 according to the preset propagation path. Therefore, in this application, a reflective layer 30 is provided on the outer surface 110 of the first dielectric layer 11, so that when the incident light propagates to the outer surface 110 of the first dielectric layer 11, the reflective layer 30 can perform total internal reflection of the light. That is, the reflective layer 30 blocks the pollutants, fingerprints, glue and other substances outside the total internal reflection propagation path of the incident light, thereby avoiding the reduction in light efficiency caused by the change in the propagation path of the light entering the area of ​​the contaminated outer surface 110 of the first dielectric layer 11.

[0055] When light enters the composite layer 10, the grating 20 couples the light into the total internal reflection region, forming total internal reflection propagation. As the light passes through the first dielectric layer 11 during total internal reflection propagation, the reflective layer 30 on the outer surface 110 of the first dielectric layer 11 reflects the light back into the total internal reflection region, allowing the light to propagate along a predetermined total internal reflection path. This reduces the impact of changes in the surface state of the outer surface 110 of the first dielectric layer 11 on the total internal reflection propagation. Consequently, the optical waveguide assembly 100 consistently maintains good luminous efficiency and contrast, resulting in a stable and reliable display effect and significantly improving the user experience.

[0056] In this application, the reflective layers 30, which are spaced apart on the outer surface 110 of the first dielectric layer 11, can ensure that light can achieve total internal reflection propagation without obstructing the transmission of external light to the composite layer 10, and thus will not reduce the visible area of ​​the waveguide product.

[0057] Understandably, compared to the situation in related technologies where the surface of the total reflection area in optical waveguide products is contaminated, causing light to be absorbed or scattered by contaminants during total reflection, resulting in a decrease in waveguide luminous efficiency and contrast, the optical waveguide component 100 of this application selectively provides multiple reflective layers 30 on the outer surface 110 of the first dielectric layer 11. This isolates contaminants to the side of the reflective layer 30 away from the first dielectric layer 11, so that contaminants do not affect the surface state of the outer surface 110, and light can propagate through total reflection in the total reflection area according to a preset path.

[0058] In some possible embodiments of this invention, the reflective layer 30 is a metal reflective film or a multilayer dielectric reflective film. By using these reflective films, it is possible to both reflect light propagating onto the reflective layer 30 without absorbing it, and to isolate contaminants or other adhering materials on the back side of the reflective layer 30 away from the first dielectric layer 11.

[0059] Optionally, when the reflective layer 30 is a metal reflective film, a silver film or an aluminum film can be selected. The silver film has a high reflectivity, especially for visible light, and has excellent reflective performance. The aluminum film also has a high reflectivity, and aluminum oxide can be formed on the surface of the aluminum film, which can provide further protection for the reflective layer 30 near the dielectric layer.

[0060] In some further embodiments, when using a metal reflective film, the thickness is controlled within the range of 200nm to 400nm. This ensures that the metal reflective film maintains its reflectivity without affecting the overall thickness of the optical waveguide assembly 100, preventing light transmission. For example, the thickness of the metal reflective film can be 200nm, 230nm, 270nm, 300nm, 310nm, 320nm, 350nm, or 400nm. If the metal reflective film is too thin, light may be transmitted, and the reflectivity may not meet the requirements; if the metal reflective film is too thick, the optical waveguide assembly 100 will be too heavy.

[0061] Optionally, when the reflective layer 30 is a multilayer dielectric reflective film, alternating layers of non-metallic oxide reflective films and metallic oxide films can be used. For example, silicon dioxide thin films and titanium dioxide thin films can be alternately stacked. This ensures that the multilayer dielectric reflective film maintains its reflectivity without affecting the overall thickness of the optical waveguide component 100, preventing light from passing through. Silicon dioxide thin films are low-refractive-index materials, while titanium dioxide thin films are high-refractive-index materials. By alternating stacks of these two materials with different refractive indices, a periodic structure can be formed, resulting in higher light reflectivity.

[0062] In some further embodiments, when using a multilayer dielectric reflective film, the thickness is controlled within the range of 300nm to 400nm, for example, values ​​such as 300nm, 320nm, 330nm, 350nm, 370nm, 385nm, or 400nm. If the multilayer dielectric reflective film is too thin, light can easily pass through, resulting in decreased reflectivity; if the multilayer dielectric reflective film is too thick, the optical waveguide component 100 will be too heavy. Therefore, this application controls the thickness of the multilayer dielectric reflective film within the range of 300nm to 400nm, which can achieve a lightweight optical waveguide component 100 while ensuring good reflectivity.

[0063] In some further embodiments, when using a multilayer dielectric reflective film, the thickness is controlled within the range of 300nm to 400nm, for example, values ​​such as 300nm, 320nm, 330nm, 350nm, 370nm, 385nm, or 400nm. If the multilayer dielectric reflective film is too thin, light can easily pass through, resulting in decreased reflectivity; if the multilayer dielectric reflective film is too thick, the optical waveguide component 100 will be too heavy. Therefore, this application controls the thickness of the multilayer dielectric reflective film within the range of 300nm to 400nm, which can achieve a lightweight optical waveguide component 100 while ensuring good reflectivity.

[0064] In some embodiments of this utility model, such as Figure 1 , Figures 4 to 8 As shown, light passes through the grating 20 and is incident on the total internal reflection region of the first dielectric layer 11. The area on the outer surface 110 of the first dielectric layer 11 that the incident light reaches during the total internal reflection is the first region 111. The reflective layer 30 is disposed in a portion of the first region 111. In other words, this invention has multiple first regions 111, and the reflective layer 30 is only selectively disposed in a portion of the first regions 111, so that the reflective layer 30 will not block external light from entering the human eye, nor will it block light from propagating to the user's eye.

[0065] In some further embodiments of this utility model, the reflective layer 30 is disposed in the first region 111, and the reflective layer 30 is disposed corresponding to the total reflection region, and is arranged in an array on the outer surface 110 of the first dielectric layer 11. The array here can be a regular array, such as multiple reflective layers 30 arranged in a rectangular array; or, for example, the line connecting the geometric centers of multiple reflective layers 30 forms an arc, so that multiple reflective layers 30 form an arc array; or, for example, multiple reflective layers 30 arranged in a circular array, etc.

[0066] In some further embodiments of this utility model, the light propagates periodically during total internal reflection within the total internal reflection region. A reflective layer 30 is disposed in the first region 111, and multiple reflective layers 30 are evenly spaced on the first dielectric layer 11. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0067] Taking a parallel incident beam as an example, the angle between the parallel beam and the normal (dashed line) is the angle of incidence α; the incident points are x1 and x2, as shown below. Figure 4As shown, when a total reflection region is formed only in the first dielectric layer 11, the thickness of the first dielectric layer 11 is D1 (nm), the grating period is d (unit nm), the refractive index of the first dielectric layer 11 is n, the diffraction order is m (which can be 0, ±1, ±2, etc., positive integers or negative integers), the diffraction angle is β, and the wavelength λ of the incident light (unit nm) is determined by the diffraction formula: nmλ=d(sinα+sinβ), then the diffraction angle β=arcsin(nmλ / d-sinα). When the incident angle α of the incident light is determined, the light source is determined, the diffraction order is determined, the refractive index n and thickness D1 of the first dielectric layer 11 in the total reflection region through which the light passes are determined, and the incident point of the incident light is determined; then, the setting position of the reflective layer 30 can be confirmed according to the following formulas: x1'=x1+D1tanβ, x2'=x2+D1tanβ. In the non-grating region, the total internal reflection period is 2D1tanβ. Therefore, the first region 111 of the selectable reflective layer 30 is determined by the following formulas: x1' = x1 + kD1tanβ, x2' = x2 + kD1tanβ, where k is a positive integer. By considering the positions of multiple x1's and x2's, the periodically distributed first regions 111 on which the reflective layer 30 can be set can be identified. In a specific embodiment, some reflective layers 30 can be continuously disposed on multiple first regions 111 spaced at intervals of 2D1tanβ on the outer surface 110. These first regions 111 are closer to the incident light point, ensuring that the incident light, after entering the first dielectric layer 11, is unaffected by contaminants during total internal reflection propagation. The concentrated reflective layers 30 in these locations also do not block light from the external environment from entering the human eye. For example, when k takes values ​​of 1, 3, and 5, the reflective layers 30 are disposed on the first region 111. The positions can be (x1+D1tanβ) to (x2+D1tanβ), (x1+3D1tanβ) to (x2+3D1tanβ) and (x1+5D1tanβ) to (x2+5D1tanβ). The width of each of these first regions 111 is x2-x1. The distance between two adjacent first regions 111 is 2D1tanβ. After the reflective layer 30 is placed in these first regions 111, three reflective layers 30 can be evenly spaced in the three first regions 111.

[0068] In some embodiments of this utility model, the same reflective layer 30 is used to reflect the light rays that pass through the outer surface 110 of the first dielectric layer 11 once during total reflection propagation in the total reflection region. The light rays are formed by the total reflection of the light rays at the edge of the beam with the same incident angle and the farthest distance in the total reflection region. The reflective layer 30 reflects the light rays back to the total reflection region. The minimum size of the reflective layer 30 is greater than or equal to the displacement difference of the light rays at the edge of the beam when they first propagate to the outer surface 110 of the first dielectric layer 11. That is, the arrangement width of the reflective layer 30 should cover the first region 111, that is, the minimum width of the reflective layer 30 should be x2-x1, so that when all the parallel light rays of the beam are incident into the composite layer 10, they can be completely reflected by the reflective layer 30 on the first region 111, so that the light rays at the edge of the beam that are the farthest distance can also be completely reflected back to the total reflection region by the reflective layer 30 when they reach the outer surface 110 of the first dielectric layer 11.

[0069] Continuing with the specific embodiments described above, when k takes values ​​of 1, 3, and 5, and a reflective layer 30 is provided in each of the three corresponding first regions 111, the reflective layer 30 is disposed within the three first regions 111, so that light rays within a distance between the edge of the beam (i.e., all parallel light rays of the incident beam) can be totally reflected by a reflective layer 30. This ensures that a beam of light within a preset distance range can be reflected by the reflective layer 30 when it reaches the first dielectric layer 11 for the first, second, and third times. Furthermore, the maximum length of the reflective layer 30 should not exceed x2-x1+2D1tanβ, so that adjacent reflective layers 30 can form a gap, thus preventing external light from being blocked from entering the human eye.

[0070] In some embodiments, the minimum deployment area of ​​a single reflective layer 30 is limited to the maximum edge of the outer surface 110 of the first dielectric layer 11, covering the light rays at different incident angles in the beam that first propagate to the outermost edge of the first dielectric layer 11, so that the reflective layer 30 can effectively achieve total internal reflection of the light rays in the entire beam. Therefore, the deployment position and deployable area of ​​the reflective layer 30 in this application can be calculated based on the area size when the beam hits the grating 20, the different incident angles of the light rays when the beam enters the composite layer 10 and forms total internal reflection, and the aforementioned formula.

[0071] In some embodiments of this utility model, the displacement of the reflective layer 30 on the outer surface 110 of the first dielectric layer 11 can be determined according to the position of the first region 111, as shown by the aforementioned formulas x1'=x1+kD1tanβ, x2'=x2+kD1tanβ. These displacements are positively correlated with the position of the incident point of the light in the total reflection region (e.g., x1, x2), the diffraction angle β of the light in the total reflection region, the thickness of the total reflection region, and the number of times the light propagates in the total reflection region, respectively.

[0072] Depending on the structure and parameters of the grating 20, for optical waveguide components 100 where the total internal reflection propagation times are high (i.e., the value of k is large, such as k being greater than 100), reflective layers 30 can be arranged in multiple first regions 111 corresponding to positions with smaller k values; when the k value is large, reflective layers 30 are arranged in a portion of the corresponding first regions 111; when the k value is in the middle of the threshold range, reflective layers 30 are arranged in a portion of the corresponding first regions 111. Therefore, in these embodiments, the optical waveguide components 100 experience a high number of total internal reflection propagations, and the light undergoes more total internal reflections in the first few reflections. When the light is at a smaller value, the reflective layer 30 is placed on more of the first regions 111 of the outer surface 110 of the first dielectric layer 11. When the k value is larger or in the middle, the reflective layer 30 is placed on fewer of the first regions 111 of the outer surface 110 of the first dielectric layer 11. This allows the light to undergo total internal reflection efficiently during the initial propagation process, reduces the amount of external light blocked by the reflective layer 30, and does not obstruct the view of the human eye.

[0073] In some embodiments of this utility model, such as Figure 1 and Figure 4 As shown, the number of reflective layers 30 disposed on the surface of the first dielectric layer 11 closer to the coupling grating 21 is greater than the number of reflective layers 30 disposed closer to the coupling grating 22. Since the coupling grating 22 is closer to the visible area of ​​the human eye, fewer reflective layers 30 are disposed on the outer surface 110 of the corresponding first dielectric layer 11 near the coupling grating 22, which can effectively prevent the reflective layers 30 from blocking light from entering the human eye; while more reflective layers 30 are disposed on the outer surface 110 of the corresponding first dielectric layer 11 near the coupling grating 21, which makes it less likely to block light from propagating to the human eye, and also allows the light to propagate efficiently through total internal reflection during the initial propagation process, and is less likely to be affected by changes in the state of the outer surface 110.

[0074] In other words, the total cross-sectional area of ​​the reflective layers 30 disposed on the surface of the first dielectric layer 11 closer to the coupling grating 21 is greater than the total cross-sectional area of ​​the reflective layers 30 disposed closer to the coupling grating 22, so that the reflective layers 30 will not block the light near the coupling grating 22 from being transmitted to the human eye.

[0075] In some embodiments of this invention, the coupling grating 21 and the coupling grating 22 are disposed on the inner surface of the first dielectric layer 11, that is, on the side of the first dielectric layer 11 facing the second dielectric layer 12. In a specific embodiment, both the coupling grating 21 and the coupling grating 22 are formed using nanoimprint lithography, and the adhesive layer surrounding the coupling grating 21 and the coupling grating 22 serves as the second dielectric layer 12.

[0076] In some embodiments of this utility model, such as Figure 2 As shown, the reflective layer 30 is disposed in a second region 112 on the side of the first dielectric layer 11 away from the coupling grating 21. Typically, as... Figure 2 and Figure 12 As shown, the optical engine 200 needs to be set with a corresponding coupling grating 21 so that the light emitted by the optical engine 200 is incident into the coupling grating 21 at a certain angle. The coupling grating 21 then further transmits the incident light to the total internal reflection region and propagates along the total internal reflection path. When fixing the optical engine 200, adhesive is usually used. If adhesive is applied directly to the outer surface 110 of the first dielectric layer 11, the refractive index of the adhesive will be different from that of the first dielectric layer 11, which will change the state of the outer surface 110 of the first dielectric layer 11. If the light in the total internal reflection region passes through these adhesive layers during the total internal reflection process, the adhesive layers will cause part of the incident light beam to be refracted through the first dielectric layer 11 instead of being totally internally reflected in the first dielectric layer 11, thus affecting the total internal reflection transmission of the incident light beam. Therefore, by defining the area where the fixed optical engine 200 needs to be fixed as the second area 112, and setting the reflective layer 30 in the second area 112 where the adhesive needs to be applied and at the position where the light needs to pass through in the total internal reflection path, the reflective layer 30 can reflect the light in the total internal reflection path, so that the light can propagate along the preset total internal reflection path.

[0077] In some further embodiments of this utility model, such as Figure 9 As shown, the reflective layer 30 is disposed in the second region 112. The reflective layer 30 is arranged in a ring on the outer surface 110 of the first dielectric layer 11. In this case, adhesive can be applied to the surface of the reflective layer 30 away from the first dielectric layer 11 for connecting the optical engine 200. In these embodiments, the ring-shaped reflective layer 30 can be a complete ring or spaced out in the ring area. The optical engine 200 is usually located at a certain distance from the area visible to the human eye. Therefore, the arrangement of the reflective layer 30 in the second region 112 can be flexibly adjusted.

[0078] In some further embodiments of this utility model, such as Figure 10As shown, taking the perpendicular line from the geometric center of the coupled grating 21 through the outer surface 110 of the first dielectric layer 11 as a reference, multiple reflective layers 30 are arranged concentrically at intervals. At this time, the surface of the reflective layer 30 away from the first dielectric layer 11 can be coated with adhesive to connect the optical engine 200, making the fixation of the optical engine 200 more reliable. The multiple reflective layers 30 arranged concentrically at intervals can save the number and area of ​​reflective layers 30, thereby reducing the impact of the large number of reflective layers 30 arranged in the second region 112 on light transmission while ensuring that the adhesive on the reflective layer 30 can reliably fix the optical engine 200.

[0079] In other embodiments, such as Figure 12 As shown, when assembling the lens 300 with the optical waveguide assembly 100 and the frame 400, if the optical waveguide assembly 100 needs to be glued to the frame 400, a reflective layer 30 can be first placed at the glue application point before applying the glue. This eliminates the problem that glue adhering to the surface of the optical waveguide assembly 100 can affect the propagation path of the totally internally reflected light in the optical waveguide assembly 100 when the optical waveguide assembly 100 and the frame 400 are fixed together with glue. In these embodiments, the area where the reflective layer 30 is placed can also be defined as the second region 112.

[0080] In some embodiments of this utility model, such as Figure 3 As shown, the reflective layer 30 is disposed in a third region 113 of the first dielectric layer 11 that is susceptible to contamination. For example, as... Figure 12 As shown, when the optical waveguide assembly 100 is used in the near-eye display device 1000, the areas near the edge of the frame 400, near the temple 500, and near the nose pad are prone to dust accumulation or fingerprints and oil stains when the user operates the assembly, causing changes in the surface condition of the optical waveguide assembly 100. Therefore, by providing a reflective layer 30 in these third regions 113, contaminants such as dust, oil stains, and fingerprints can be isolated on the side of the reflective layer 30 away from the first dielectric layer 11, ensuring that the propagation of light from the total reflection area to the outer surface 110 of the first dielectric layer 11 can propagate along a preset total reflection path without being affected by contaminants such as dust and fingerprints. Furthermore, there can be multiple reflective layers 30 in the third region 113, with intervals between them. For example, the third region 113 located near the nose pad is usually closer to the visible area of ​​the human eye. Therefore, the intervals between the multiple reflective layers 30 can prevent the reflective layers 30 from blocking the human eye's line of sight. By setting the intervals between the reflective layers 30, it is possible to ensure total internal reflection of light and allow more light from the environment to be transmitted to the human eye, thereby improving the display contrast effect. It can also block dust, fingerprints, and oil stains from the outside of the first dielectric layer 11 to improve the reliability and stability of the optical waveguide assembly 100.

[0081] In other embodiments, the side of the optical waveguide assembly 100 away from the human body is more likely to come into contact with the hand during the wearing of glasses. A portion of the optical waveguide assembly 100 located on this side is more susceptible to scratches. Therefore, this portion of the area can also be defined as the third region 113, and the reflective layer 30 can also be located in the easily scratched third region 113.

[0082] In summary, in specific embodiments of this utility model, the reflective layer 30 may be disposed in only a portion of the first region 111, or the reflective layer 30 may be disposed in any two of the first region 111, the second region 112, and the third region 113 simultaneously, or the reflective layer 30 may be disposed in all three regions simultaneously. Meanwhile, the reflective layer 30 may be disposed directly above or below the grating 20; the reflective layer 30 may also be disposed on the outer surface 110 of the first dielectric layer 11 or the surface of the third dielectric layer 13 corresponding to the middle region between the coupling-in grating 21 and the coupling-out grating 22.

[0083] In some embodiments of this utility model, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 11 As shown, the dielectric layer also includes a second dielectric layer 12 and a third dielectric layer 13, with the opposite sides of the second dielectric layer 12 connected to the first dielectric layer 11 and the third dielectric layer 13, respectively; the grating 20 is connected to the first dielectric layer 11.

[0084] like Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 11 As shown, when a total reflection region is formed only in the first dielectric layer 11, the reflective layer 30 is disposed on the outer surface 110 of the first dielectric layer 11 on the side away from the second dielectric layer 12. In this case, the refractive index of the first dielectric layer 11 in these embodiments is greater than the refractive index of the second dielectric layer 12, and the refractive index of the first dielectric layer 11 is greater than the refractive index of air, so when the light beam is incident, a total reflection region can be formed only in the first dielectric layer 11.

[0085] like Figure 5 and Figure 6As shown, when total internal reflection regions are simultaneously formed in the first dielectric layer 11 and the second dielectric layer 12, the reflective layer 30 is disposed on the outer surface 110 of the first dielectric layer 11 away from the second dielectric layer 12. In these embodiments, the first dielectric layer 11 and the second dielectric layer 12 are made of different materials but have approximately the same refractive index. The refractive index of the first dielectric layer 11 and the second dielectric layer 12 is greater than that of the third dielectric layer 13, and the refractive index of the first dielectric layer 11 and the second dielectric layer 12 is greater than that of air. Therefore, when a light beam is incident, a total internal reflection region can be formed in the first dielectric layer 11 and the second dielectric layer 12. In these embodiments, the second dielectric layer 12 is located in the intermediate layer, and the surface state of the second dielectric layer 12 does not change. Therefore, in these embodiments, it is only necessary to provide the reflective layer 30 on the outer surface 110 of the first dielectric layer 11 away from the second dielectric layer 12 to reduce the impact of changes in the surface state of the first dielectric layer 11 on the total internal reflection propagation of light in the total internal reflection regions of the first dielectric layer 11 and the second dielectric layer 12.

[0086] In some embodiments, if the second dielectric layer 12 is an adhesive layer, then when fabricating the optical waveguide component 100, the adhesive needs to be applied to the first dielectric layer 11 by spin coating / scraping or other methods; alternatively, the adhesive can be applied to the third dielectric layer 13 by spin coating / scraping or other methods. The intermediate adhesive layer can be cured or not cured depending on the material of each dielectric layer.

[0087] like Figure 6 As shown, total internal reflection regions are simultaneously formed in the first dielectric layer 11 and the second dielectric layer 12. The thickness of the second dielectric layer 12 is D2 (nm). When light undergoes its first total internal reflection within the first dielectric layer 11, the positions where the first total internal reflection occurs on the outer surface 110 of the first dielectric layer 11 are: x1' = x1 + D1tanβ, x2' = x2 + D1tanβ. When light undergoes total internal reflection from the surface of the second dielectric layer 12 back to the outer surface 110 of the first dielectric layer 11, the positions where the second total internal reflection occurs on the outer surface 110 of the first dielectric layer 11 are calculated. X1" and X2" can be calculated using the following formulas:

[0088] X1”=X1'+(p-1)K(D1+D2)tanβ, where K is a positive integer, p is the number of total internal reflections when light propagates in the total internal reflection region, and p is greater than or equal to 3, and p takes an odd number;

[0089] X2”=X2'+(p-1)K(D1+D2)tanβ, where K is a positive integer, p is the number of total reflections when light propagates through the total reflection region, and p is greater than or equal to 3, and p takes an odd number.

[0090] Since the second dielectric layer 12 is located between the first dielectric layer 11 and the third dielectric layer 13, the surface state of the second dielectric layer 12 will not change, and there is no need to add a reflective layer 30 to the surface of the second dielectric layer 12.

[0091] like Figure 7 and Figure 8 As shown, when total internal reflection regions are simultaneously formed in the first dielectric layer 11, the second dielectric layer 12, and the third dielectric layer 13, a partial reflective layer 30 is disposed on the outer surface 110 of the first dielectric layer 11 away from the second dielectric layer 12; a partial reflective layer 30 is disposed on the outer surface 110 of the third dielectric layer 13 away from the second dielectric layer 12. In this case, the first dielectric layer 11, the second dielectric layer 12, and the third dielectric layer 13 in these embodiments are made of different materials and have approximately the same refractive index. The refractive index of the first dielectric layer 11, the second dielectric layer 12, and the third dielectric layer 13 is greater than the refractive index of air, thus forming total internal reflection regions in the first dielectric layer 11, the second dielectric layer 12, and the third dielectric layer 13. In these embodiments, both the first dielectric layer 11 and the third dielectric layer 13 are located on the surface and have a side that is easy to change in surface state. These are the outer surface 110 of the first dielectric layer 11 away from the second dielectric layer 12 and the surface of the third dielectric layer 13 away from the second dielectric layer 12, respectively. Therefore, it is necessary to set a reflective layer 30 at appropriate positions in both the first dielectric layer 11 and the third dielectric layer 13 so that light can propagate along a predetermined total internal reflection propagation path in the total internal reflection area formed by the first dielectric layer 11, the second dielectric layer 12 and the third dielectric layer 13. This can effectively prevent the phenomenon of decreased waveguide light efficiency, contrast and other display effects caused by changes in the surface state of the optical waveguide component 100.

[0092] In one embodiment of this application, as Figure 8 As shown, total internal reflection regions are simultaneously formed in the first dielectric layer 11, the second dielectric layer 12, and the third dielectric layer 13. The thickness of the second dielectric layer 12 is D2 (nm), and the thickness of the third dielectric layer 13 is D3 (nm). When light undergoes its first total internal reflection within the first dielectric layer 11, the positions where the first total internal reflection occurs on the outer surface 110 of the first dielectric layer 11 are: x1' = x1 + D1tanβ, x2' = x2 + D1tanβ. The positions X1" and X2" of the reflective layer 30 on the surface of the third dielectric layer 13 can be calculated using the following formula:

[0093] X1”=X1'+(p-1)K(D1+D2+D3)tanβ, where K is a positive integer, p is the number of total internal reflections when light propagates in the total internal reflection region, and p is greater than or equal to 2, and p takes an even number;

[0094] X2”=X2'+(p-1)K(D1+D2+D3)tanβ, where K is a positive integer, p is the number of total reflections when light propagates through the total reflection region, and p is greater than or equal to 2, and p takes an even number.

[0095] Furthermore, when the light is totally reflected back from the surface of the third dielectric layer 13 to the outer surface 110 of the first dielectric layer 11, the positions X1”' and X2”' of the outer surface 110 of the first dielectric layer 11 can be calculated using the following formula:

[0096] X1”'=X1'+(p-1)K(D1+D2+D3)tanβ, where K is a positive integer, p is the number of total internal reflections when light propagates in the total internal reflection region, and p is greater than or equal to 3, and p takes an odd number;

[0097] X2”'=X2'+(p-1)K(D1+D2+D3)tanβ, where K is a positive integer, p is the number of total reflections when light propagates in the total reflection region, and p is greater than or equal to 3, and p takes an odd number.

[0098] It is understood that the selective provision of the reflective layer 30 on the surface of the third dielectric layer 13 in this application is similar to the principle that the reflective layer 30 on the surface of the first dielectric layer 11 is provided in part of the first region 111, in the second region 112, and in the third region 113, and will not be elaborated here.

[0099] In this utility model, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first," "second," and "third" may explicitly or implicitly include one or more of the stated features.

[0100] In some embodiments of this utility model, such as Figure 11As shown, when the second dielectric layer 12 is an air layer, the composite layer 10 further includes an adhesive layer 14. The adhesive layer 14 is connected to the edge region between the third dielectric layer 13 and the first dielectric layer 11. The reflective layer 30 is disposed on the outer surface 110 of the first dielectric layer 11 on the side away from the second dielectric layer 12. In these embodiments, the outer surface 110 of the first dielectric layer 11 is in contact with air, and the inner surface of the first dielectric layer 11 is also in contact with air. When an air layer is used as the second dielectric layer 12, light is coupled into the first dielectric layer 11 under the action of the grating 20 and undergoes total internal reflection. At this time, a total internal reflection region is formed only in the first dielectric layer 11. The adhesive layer 14 disposed at the edge can connect the first dielectric layer 11 and the third dielectric layer 13 into a whole and seal the space between the two dielectric layers, so that the encapsulated optical waveguide component 100 has good airtightness, the physical and chemical state of the second dielectric layer 12 remains stable, and the reliability of light propagating during total internal reflection in the first dielectric layer 11 is good. The adhesive layer 14 can be a solid adhesive or a liquid adhesive.

[0101] In some embodiments of this invention, when a reflective layer 30 is provided on a selected area of ​​the first dielectric layer 11 and / or the third dielectric layer 13, physical methods such as evaporation deposition and sputtering deposition can be used for deposition, as can chemical methods. Alternatively, an adhesive can be used to attach the reflective layer 30 to the corresponding position. When using adhesive on the first dielectric layer 11, the refractive index of the adhesive should be the same as or close to the refractive index of the first dielectric layer 11; when using adhesive on the third dielectric layer 13, the refractive index of the adhesive should be the same as or close to the refractive index of the third dielectric layer 13.

[0102] In some embodiments of this utility model, the first dielectric layer 11 serves as a base layer, and the material is one or more selected from glass, sapphire, polycarbonate, acrylic, cyclic olefin copolymer plastics, or cyclic olefin polymers; the third dielectric layer 13 serves as a protective layer, and the material is one or more selected from glass, polycarbonate, acrylic, cyclic olefin copolymer plastics, or cyclic olefin polymers. The first dielectric layer 11 and the third dielectric layer 13, using the above-mentioned materials, have good transparency, are lightweight, possess certain mechanical strength and toughness, and are not easily broken by external forces, which is beneficial for supporting and encapsulating the grating 20, and can also effectively protect the grating 20. For example, when glass is used, it is easy to process, colorless and transparent, and has good support. When polycarbonate (PC) is used, it is colorless and transparent, heat-resistant, impact-resistant, inexpensive, and readily available. When acrylic (PMMA, polymethyl methacrylate) is used, it has high transmittance, good toughness, high hardness, is not easily broken, and is easy to bond. When cyclic olefin copolymer plastics (COC plastics) are used, they exhibit high transparency, excellent low-temperature impact resistance, and elasticity. When cyclic olefin polymers (COP) are used, they possess high transparency, high gloss, high water vapor barrier properties, high rigidity, high strength, and excellent chemical resistance. Of course, the materials chosen for the first dielectric layer 11 and the third dielectric layer 13 of this invention are not limited to the aforementioned material types and can also be other polymeric materials with similar properties.

[0103] The material of the second dielectric layer 12 in this application can be similar to the materials selected for the first dielectric layer 11 and the third dielectric layer 13, or it can be air. In the same optical waveguide assembly 100, the materials specifically selected for the second dielectric layer 12 should be different from those selected for the first dielectric layer 11 and the third dielectric layer 13. The specific types of materials required for the first dielectric layer 11, the second dielectric layer 12 and the third dielectric layer 13 can be determined as needed.

[0104] In some embodiments of this application, the grating 20 is disposed on the same side of the first dielectric layer 11, for example, the side facing the second dielectric layer 12. The grating 20 is encapsulated in the composite layer 10 to form a whole. The first dielectric layer 11 can provide a certain support for the grating 20, and the third dielectric layer 13 can provide a certain protection for the grating 20. The position of the grating 20 is stable, enabling incident light within a preset angle range to be coupled into the total internal reflection region, and to couple the light in the total internal reflection region into the human eye. In optional embodiments, the grating 20 is fabricated on the surface of the first dielectric layer 11 using processes such as nanoimprinting or etching to form a micro / nano grating structure.

[0105] The near-eye display device 1000 proposed in this application is described below.

[0106] According to the near-eye display device 1000 proposed in this utility model, combined with Figure 2 and Figure 12 As shown, it includes: an optomechanical system 200 and an optical waveguide assembly 100 of the aforementioned embodiments. The optomechanical system 200 is used to emit signal light, and the optomechanical system 200 is configured to be coupled into the grating 21.

[0107] As can be seen from the above technical solution, the near-eye display device 1000 proposed by this utility model emits light from the optical engine 200 toward the coupling grating 21. The coupling grating 21 couples the light into the total internal reflection area and propagates it through total internal reflection within the total emission area. When the light passes through the first dielectric layer 11 on the surface during the total internal reflection propagation, the reflective layer 30 provided on the first dielectric layer 11 reflects the light back to the total internal reflection area, enabling the light to propagate along the preset total internal reflection path. This avoids the change in the surface state of the outer surface 110 of the first dielectric layer 11 from affecting the total internal reflection propagation of the light. The reflective layers 30, which are spaced apart on the outer surface 110 of the first dielectric layer 11, can ensure that the light can achieve total internal reflection propagation without obstructing the transmission of external light to the composite layer 10. Therefore, they will not interfere with the visible area of ​​the human eye, making the entire near-eye display device 1000 image clear. It can achieve virtual and real combination and enhanced display effects, and the overall display effect is guaranteed.

[0108] In other embodiments, when light passes through the total internal reflection area formed by the first dielectric layer 11, the second dielectric layer 12, and the third dielectric layer 13 simultaneously, multiple reflective layers 30 can be selectively disposed on the surface of the third dielectric layer 13. This allows the light to continue its total internal reflection propagation along a predetermined path when it reaches the surface of the third dielectric layer 13, without being affected by changes in the surface state of the third dielectric layer 13. The selectively disposed reflective layers 30 on a portion of the surface of the third dielectric layer 13 also ensure that light can achieve total internal reflection propagation without obstructing external light transmission to the composite layer 10. Therefore, it does not interfere with the visible area of ​​the human eye, resulting in clear imaging of the entire near-eye display device 1000. It can achieve effects such as virtual-real image combination and enhanced display, ensuring overall display quality.

[0109] In some specific embodiments, such as Figure 12 As shown, two lenses 300 with optical waveguide assemblies 100 are connected at an interval in the frame 400. A temple 500 is connected to each end of the frame 400. The optical engine 200 is connected to the frame 400 and the lenses 300 via a corresponding coupling grating 21 (not shown). In these embodiments, corresponding to the location where the optical engine 200 is connected, multiple spaced reflective layers 30 are provided on the second region 112 of the optical waveguide assembly 100. Adhesive is applied to the side of the reflective layer 30 away from the first dielectric layer 11 to connect the corresponding structure of the optical engine 200.

[0110] In a more specific embodiment, the support of the optomechanism 200 is connected in the second region 112 of the outer surface 110 of the first dielectric layer 11, thereby enabling the optomechanism 200 to be configured to correspond to the coupling grating 21.

[0111] The optical device proposed in this application is described below.

[0112] The optical device proposed according to this utility model includes the optical waveguide assembly 100 of the foregoing embodiments. The optical device includes, but is not limited to, head-up display (HUD), augmented reality (AR) device, virtual reality (VR) device, etc.

[0113] As can be seen from the above technical solution, the optical device proposed by this utility model can achieve total internal reflection of light along a predetermined path by using the aforementioned optical waveguide component 100, thereby reducing or avoiding the influence of changes in the surface state of the outer surface 110 of the first dielectric layer 11 on the total internal reflection propagation of light. The optical device has good imaging effect and improves user experience.

[0114] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model 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 utility model, and these modifications or substitutions should all be covered within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. An optical waveguide component, characterized in that, include: A composite layer comprising multiple dielectric layers, the dielectric layers including a first dielectric layer located on the surface, wherein at least a total reflection region is formed in the first dielectric layer; A grating is disposed on the same side of the first dielectric layer. The grating includes an input grating and an output grating. The input grating is used to couple light entering the composite layer into the total internal reflection region to form total internal reflection propagation. The output grating is used to couple at least a portion of the light in the total internal reflection region out of the composite layer. A reflective layer is disposed on the outer surface of the first dielectric layer, and the reflective layer reflects the light from the total reflection region so that the light continues to propagate along the total reflection path. The reflective layer may be selectively disposed in multiple regions on the outer surface of the first dielectric layer, and the reflective layer in at least one region is spaced apart.

2. The optical waveguide assembly as described in claim 1, characterized in that, The light rays pass through the coupling grating and are incident on the total internal reflection region of the first dielectric layer. The region on the outer surface of the first dielectric layer reached by the light rays during total internal reflection is the first region. The reflective layer is disposed in a portion of the first region; and / or... The reflective layer is disposed in the second region of the first dielectric layer opposite to the coupling grating; and / or The reflective layer is located in a third region of the first dielectric layer that is susceptible to contamination.

3. The optical waveguide assembly as described in claim 2, characterized in that, The reflective layer is disposed in the first region, and the reflective layer is arranged in an array on the outer surface of the first dielectric layer in an extension direction parallel to the total reflection region; or... The light has a period when it is totally reflected in the total reflection region. The reflective layer is disposed in the first region, and a plurality of the reflective layers are evenly spaced on the first dielectric layer.

4. The optical waveguide assembly as described in claim 3, characterized in that, The same reflective layer is used to reflect light rays that pass through the outer surface of the first dielectric layer once during total reflection propagation in the total reflection region. The light rays are formed by total reflection of the beam edge rays with the same incident angle and the farthest distance in the total reflection region. The reflective layer reflects the light rays back to the total reflection region. The minimum size of the reflective layer is greater than or equal to the displacement difference of the beam edge rays when they first propagate to the outer surface of the first dielectric layer.

5. The optical waveguide assembly as described in claim 3, characterized in that, The number of reflective layers disposed on the surface of the first dielectric layer closer to the coupling grating is greater than the number of reflective layers disposed on the surface closer to the coupling grating; or, the total cross-sectional area of ​​the reflective layers disposed on the surface of the first dielectric layer closer to the coupling grating is greater than the total cross-sectional area of ​​the reflective layers disposed on the surface closer to the coupling grating.

6. The optical waveguide assembly as described in claim 3, characterized in that, The displacement of the reflective layer on the outer surface of the first dielectric layer is positively correlated with the position of the incident point of the light in the total reflection region, the diffraction angle of the light in the total reflection region, the thickness of the total reflection region, and the number of times the light propagates in the total reflection region.

7. The optical waveguide assembly as described in claim 2, characterized in that, The reflective layer is disposed in the second region. The reflective layer is arranged in a ring on the outer surface of the first dielectric layer. Alternatively, multiple reflective layers are arranged concentrically at intervals, with the geometric center of the coupled grating passing through the outer surface of the first dielectric layer as a reference.

8. The optical waveguide assembly as described in any one of claims 1 to 7, characterized in that, The dielectric layer further includes a second dielectric layer and a third dielectric layer, with the first dielectric layer and the third dielectric layer respectively connected to opposite sides of the second dielectric layer; If a total reflection region is formed only in the first dielectric layer, the reflective layer is disposed on the outer surface of the first dielectric layer away from the second dielectric layer; When total reflection regions are formed simultaneously in the first dielectric layer and the second dielectric layer, the reflective layer is disposed on the outer surface of the first dielectric layer away from the second dielectric layer; When total reflection regions are simultaneously formed in the first dielectric layer, the second dielectric layer, and the third dielectric layer, a portion of the reflective layer is disposed on the outer surface of the first dielectric layer away from the second dielectric layer; a portion of the reflective layer is disposed on the surface of the third dielectric layer away from the second dielectric layer.

9. The optical waveguide assembly as described in claim 8, characterized in that, If the refractive index of the first dielectric layer is greater than that of the second dielectric layer, and the refractive index of the first dielectric layer is greater than that of air, then the total internal reflection region is formed in the first dielectric layer; or... The first and second dielectric layers are made of different materials and have approximately the same refractive index. The refractive index of the first and second dielectric layers is greater than that of the third dielectric layer. The refractive index of the first and second dielectric layers is greater than that of air. Thus, the total internal reflection region is formed in the first and second dielectric layers. or, The first, second, and third dielectric layers are made of different materials and have approximately the same refractive index. The refractive index of the first, second, and third dielectric layers is greater than that of air, thus forming the total internal reflection region in the first, second, and third dielectric layers.

10. The optical waveguide assembly as described in claim 8, characterized in that, When the second medium layer is an air layer, the composite layer further includes an adhesive layer, which is connected to the edge region between the third medium layer and the first medium layer, and the reflective layer is disposed on the outer surface of the first medium layer away from the second medium layer.

11. The optical waveguide assembly as described in any one of claims 1 to 7, characterized in that, The reflective layer includes a metal reflective film or a multilayer dielectric reflective film.

12. The optical waveguide assembly as described in claim 11, characterized in that, The reflective layer is a metal reflective film with a thickness ranging from 200 nm to 400 nm; or, the reflective layer is a multilayer dielectric reflective film with a thickness ranging from 300 nm to 400 nm.

13. A near-eye display device, characterized in that, include: Optical engines are used to transmit signal light; The optical waveguide assembly as described in any one of claims 1 to 12, wherein the optomechanical system is configured corresponding to the coupling grating.

14. An optical device, characterized in that, Includes the optical waveguide component as described in any one of claims 1 to 12.

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