Optical waveguide assembly and augmented reality display device

Abstract

The invention provides an optical waveguide assembly and an augmented reality display device. The optical waveguide assembly comprises a first cover plate, a first viscous layer and at least one optical waveguide layer, the first viscous layer adheres to the first cover plate and the optical waveguide layer, the optical waveguide layer comprises a waveguide sheet, a grating and a flat layer, the grating is located on the surface, close to the first cover plate, of the waveguide sheet, and the flat layer fills a space defined by the grating and the waveguide sheet. The height of the flat layer is larger than or equal to that of the grating, the refractive index of the grating is larger than that of the flat layer, and the difference between the refractive index of the grating and the refractive index of the flat layer is larger than or equal to 0.7. Therefore, the space defined by the optical waveguide layer and the grating is filled with the flat layer, and the problems of uneven air gaps, rainbow lines and the like can be relieved and even solved at least to a certain extent; the first cover plate and the optical waveguide layer are bonded through the first adhesive layer, so that the overall stability of the optical waveguide assembly is improved; the difference between the refractive index of the grating and the refractive index of the flat layer is large, and the display effect can be improved.

Description

Technical Field

[0001] The present invention relates to the field of display technologies, and more specifically, to a waveguide component and an augmented reality display device. Background Art

[0002] Currently, the waveguide of an AR (Augmented Reality) display device uses edge area coating of a sealing adhesive as the encapsulation method. This method generally has problems such as uneven air gaps and easy generation of rainbow patterns. At the same time, the waveguide substrate has poor drop resistance. In addition, the display effect of the augmented reality display device still needs to be improved.

[0003] Therefore, the current waveguide components and augmented reality display devices still need to be improved. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems in the related technologies to some extent.

[0005] In one aspect of the present invention, a waveguide component is proposed. In some embodiments of the present invention, the waveguide component includes a first cover plate, a first adhesive layer, and at least one waveguide layer. The first adhesive layer bonds the first cover plate and one of the waveguide layers. The waveguide layer includes a waveguide sheet, a grating, and a flat layer. The grating is located on the surface of the waveguide sheet close to the first cover plate. The grating includes an input grating and an output grating. The flat layer fills the space defined by the grating and the waveguide sheet. The height of the flat layer is greater than or equal to the height of the grating. The refractive index of the grating is greater than the refractive index of the flat layer, and the difference between the refractive index of the grating and the refractive index of the flat layer is ≥ 0.7. Thus, the space defined by the waveguide layer and the grating is filled by the flat layer, which can alleviate or even solve the problems such as uneven air gaps and generation of rainbow patterns to some extent; by bonding the first cover plate and the waveguide layer with the first adhesive layer, the first cover plate and the waveguide layer can be firmly combined, which is beneficial to improving the overall stability of the waveguide component; the large difference between the refractive index of the grating and the refractive index of the flat layer makes the waveguide component have better performance in adjusting the light transmission path, which is beneficial to improving the display effect.

[0006] In some embodiments of the present invention, the waveguide component includes at least two waveguide layers, and adjacent waveguide layers are bonded by a second adhesive layer. Bonding adjacent waveguide layers with a whole-layer second adhesive layer is beneficial to further improving the overall stability of the waveguide component. Moreover, the whole-layer second adhesive layer can serve as a stress point, which is beneficial to improving the drop resistance of the waveguide component.

[0007] In some embodiments of the present invention, the number of the optical waveguide layers is 1, 2 or 3. The optical waveguide layers with the above numbers can all adjust the propagation path of light, so that the light enters the observer's eyes through the optical waveguide layers.

[0008] In some embodiments of the present invention, the refractive index of the grating ≥ 2.3, and the refractive index of the flat layer is 1.1 - 1.3. Thus, the refractive index difference between the flat layer and the grating is larger, which is beneficial to further improving the display effect.

[0009] In some embodiments of the present invention, the material of the grating includes gallium nitride, the material of the waveguide sheet includes gallium nitride, and the material of the flat layer includes UV glue.

[0010] In some embodiments of the present invention, the grating satisfies at least one of the following conditions: the period of the grating is 200 nm - 500 nm; the height of the grating is 50 nm - 500 nm; the duty cycle of the grating is 0.2 - 0.8.

[0011] In some embodiments of the present invention, the grating satisfies one of the following conditions: the grating is a rectangular grating; the grating is an inclined grating, and the inclination angle of the grating is 30° - 80°; the grating is a blazed grating, and the inclination angle of the grating is 30° - 80°; the grating is a metasurface grating.

[0012] In some embodiments of the present invention, the optical waveguide assembly further includes a second cover plate, the second cover plate is located on the side of the optical waveguide layer farthest from the first cover plate away from the first cover plate, and the second cover plate is bonded to the optical waveguide layer farthest from the first cover plate through a third adhesive layer. Thus, both the second cover plate and the first cover plate can protect the optical waveguide layer, which is beneficial to further improving the stability of the optical waveguide assembly and prolonging the service life of the optical waveguide assembly.

[0013] In some embodiments of the present invention, the material of the first cover plate and the material of the second cover plate independently include glass, PET or PI.

[0014] On the other hand of the present invention, the present invention provides an augmented reality display device. In some embodiments of the present invention, the augmented reality display device includes a microdisplay, a collimating component, and the optical waveguide assembly described above. Thus, the augmented reality display device has all the features and advantages of the optical waveguide assembly described above, which will not be elaborated here. Generally speaking, the augmented reality display device has good display effect and overall stability. Description of the Drawings

[0015] Figure 1 Shows a schematic structural diagram of an optical waveguide assembly according to an embodiment of the present invention;

[0016] Figure 2 Shows a schematic structural diagram of an optical waveguide component according to another embodiment of the present invention;

[0017] Figure 3 Shows a schematic structural diagram of an optical waveguide component according to yet another embodiment of the present invention;

[0018] Figure 4 Shows a schematic structural diagram of an optical waveguide component according to yet another embodiment of the present invention;

[0019] Figure 5 Shows a schematic structural diagram of an optical waveguide component according to yet another embodiment of the present invention;

[0020] Figure 6 Shows a schematic structural diagram of an optical waveguide component according to yet another embodiment of the present invention;

[0021] Figure 7 Shows a schematic structural diagram of an optical waveguide component according to yet another embodiment of the present invention;

[0022] Figure 8 Shows a schematic structural diagram of an optical waveguide component in the related art;

[0023] Figure 9 Shows a partial schematic structural diagram of an optical waveguide component according to an embodiment of the present invention;

[0024] Figure 10 Shows a partial schematic structural diagram of an optical waveguide component according to another embodiment of the present invention;

[0025] Figure 11 Shows a flowchart for manufacturing an optical waveguide component according to an embodiment of the present invention;

[0026] Figure 12 Shows a flowchart for manufacturing an optical waveguide component according to another embodiment of the present invention;

[0027] Figure 13 Shows a schematic structural diagram of an augmented reality display device according to an embodiment of the present invention;

[0028] Figure 14 Shows a schematic structural diagram of an augmented reality display device according to another embodiment of the present invention;

[0029] Figure 15 Shows a schematic structural diagram of an augmented reality display device according to yet another embodiment of the present invention.

[0030] Description of reference numerals:

[0031] 100: First cover plate; 200: First adhesive layer; 300: Optical waveguide layer; 310: Waveguide sheet; 320: Grating; 321: Coupling-in grating; 322: Coupling-out grating; 330: Flattening layer; 400: Second adhesive layer; 500: Second cover plate; 600: Third adhesive layer; 2000: Microdisplay; 3000: Collimation component; 1: Cover plate; 2: Nanograting; 3: Waveguide substrate; 4: Frame adhesive. Detailed implementation manners

[0032] Embodiments of the present invention will be described in detail below. The embodiments described below are exemplary and are only used to explain the present invention and should not be construed as a limitation to the present invention. For those not specified in the embodiments regarding specific technologies or conditions, they shall be carried out according to the technologies or conditions described in the literature in this field or according to the product specifications.

[0033] In one aspect of the present invention, the present invention provides an optical waveguide assembly. In some embodiments of the present invention, with reference to Figures 1 to 7 , the optical waveguide assembly may include a first cover plate 100, a first adhesive layer 200, and at least one optical waveguide layer 300. The first adhesive layer 200 bonds the first cover plate 100 and one optical waveguide layer 300. With reference to Figures 1 to 7 , the optical waveguide layer 300 may include a waveguide sheet 310, a grating 320, and a flattening layer 330. The grating 320 is located on the surface of the waveguide sheet 310 close to the first cover plate 100. The grating 320 may include a coupling-in grating 321 and a coupling-out grating 322. The flattening layer 330 fills the space defined by the grating 320 and the waveguide sheet 310. The height of the flattening layer 330 may be greater than or equal to the height of the grating 320. The refractive index of the grating 320 is greater than that of the flattening layer 330, and the difference between the refractive index of the grating 320 and the refractive index of the flattening layer 330 ≥ 0.7. In some embodiments of the present invention, the difference between the refractive index of the grating 320 and the refractive index of the flattening layer 330 may be 0.7, 0.8, 0.9, 1, 1.1, 1.2, etc.

[0034] It should be noted that the height of the flattening layer may be greater than or equal to the height of the grating, which means that in the same optical waveguide layer, the distance between the surface of the flattening layer away from the waveguide sheet and the surface of the waveguide sheet close to the first cover plate may be greater than or equal to the height of the grating. In some specific embodiments of the present invention, with reference to Figures 1 to 4 , the height of the flattening layer 330 is greater than the height of the grating 320. In some other specific embodiments of the present invention, with reference to Figures 5 to 7 , the height of the flattening layer 330 is equal to the height of the grating 320.

[0035] Figure 8The structural schematic diagram of an optical waveguide component in the related art is shown. The cover plate 1 and the waveguide substrate 3 of the optical waveguide component are bonded by a frame adhesive 4, and the frame adhesive 4 only bonds the edge regions of the cover plate 1 and the waveguide substrate 3. An air gap will be formed between the first cover plate 1, the grating 2, the waveguide substrate 3 and the frame adhesive 4, and moreover, the air gap is uneven, and rainbow patterns are likely to occur when displaying an image. In addition, since the frame adhesive 4 only bonds the edge regions of the cover plate 1 and the waveguide substrate 3, the overall stability of the optical waveguide component is poor. The frame adhesive 4 is not a whole-layer structure and has fewer stress points, resulting in poor drop resistance of the optical waveguide component.

[0036] Compared with Figure 8 the optical waveguide component shown in, the optical waveguide component proposed by the present invention has the following advantages: the refractive index difference between the grating and the flat layer in the optical waveguide component is relatively large, which can better adjust the propagation path of light. The optical waveguide component has excellent optical characteristics, which is beneficial to improving the display effect; the flat layer fills the space defined by the grating and the waveguide sheet, eliminating the air gap, and rainbow patterns are not likely to occur when displaying an image; by bonding the first cover plate and an optical waveguide layer with a whole-layer first adhesive layer, the overall stability and drop resistance of the optical waveguide component can be improved.

[0037] In some specific embodiments of the present invention, referring to Figure 1 and Figure 4 , in the optical waveguide component, the number of optical waveguide layers 300 can be 1.

[0038] In some embodiments of the present invention, referring to Figure 2 , Figure 3 , Figures 5 to 7 , the optical waveguide component can include at least two optical waveguide layers 300, and adjacent optical waveguide layers 300 can be bonded by a second adhesive layer 400. Multiple optical waveguide layers can all adjust the propagation path of the light incident into them, so that users can experience a sense of reality beyond reality; adjacent optical waveguide layers are bonded by a whole-layer second adhesive layer, which is beneficial to further improving the overall stability and drop resistance of the optical waveguide component.

[0039] In some specific embodiments of the present invention, referring to Figure 2 , in the optical waveguide component, the number of optical waveguide layers 300 can be 2. In some other specific embodiments of the present invention, referring to Figure 3 , Figures 5 to 7 , in the optical waveguide component, the number of optical waveguide layers 300 can be 3. In still some other specific embodiments of the present invention, in the optical waveguide component, the number of optical waveguide layers can be 4, 5 or more.

[0040] In some embodiments of the present invention, the refractive index of the grating 320 ≥ 2.3, and the refractive index of the flat layer can be 1.1 - 1.3. Thus, the difference in refractive index between the grating and the flat layer is relatively large, which is conducive to improving the display effect.

[0041] In some embodiments of the present invention, the material of the grating 320 may include gallium nitride, the material of the waveguide sheet 310 may include gallium nitride, the refractive index of gallium nitride is about 2.3, the material of the flat layer may include UV glue, and the refractive index of the flat layer 330 can be 1.1 - 1.3. For example, the refractive index of the flat layer can be 1.1, 1.2, or 1.3, etc. The relatively high refractive index of gallium nitride can make the difference in refractive index between the grating and the waveguide sheet and the flat layer ≥ 1, and the optical waveguide layer can better adjust the propagation path of light, which is conducive to further improving the display effect. In some specific embodiments of the present invention, the material of the grating 320 can be gallium nitride, and the material of the waveguide sheet 310 can also be gallium nitride.

[0042] In some specific embodiments of the present invention, the material of the grating 320 is gallium nitride, the material of the waveguide sheet 310 is gallium nitride, and the material of the flat layer is UV glue.

[0043] In some embodiments of the present invention, referring to Figures 1 to 4 , the grating 320 can be a rectangular grating, and the longitudinal section of the grating is rectangular. Herein, the longitudinal section of the grating refers to the section of the grating along the thickness direction of the optical waveguide component.

[0044] In some embodiments of the present invention, referring to Figures 1 to 4 and Figure 9 , the grating 320 is a rectangular grating, and the period b (the length from one refractive index change point to the adjacent refractive index change point) of the grating can be 200 nm - 500 nm. For example, the period of the rectangular grating can be 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm, etc.

[0045] In some embodiments of the present invention, referring to Figures 1 to 4 and Figure 9 , the height h of the rectangular grating can be 50 nm - 500 nm. For example, the height of the rectangular grating can be 80 nm, 100 nm, 200 nm, 300 nm, 400 nm, 450 nm, etc.

[0046] In some embodiments of the present invention, the duty cycle of the rectangular grating can be 0.2 - 0.8. For example, the duty cycle of the rectangular grating can be 0.3, 0.4, 0.5, 0.6, 0.7, etc. Referring to Figure 9 , the duty cycle of the grating refers to the ratio of the width a of the grating to the period b of the grating.

[0047] When the period, height, and / or duty cycle of the rectangular grating are within the above ranges, it is beneficial to adjust the propagation path of light, thereby facilitating the improvement of the display effect.

[0048] In some other embodiments of the present invention, referring to Figure 5 , the grating 320 can be an inclined grating. The longitudinal cross-section of the inclined grating can be a parallelogram, and the inclination angle of the grating 320 can be 30° to 80°. For example, the inclination angle of the grating 320 can be 40°, 50°, 60°, 70°, etc. It should be noted that the inclination angle of the grating refers to the acute angle formed between the side surface of the grating and the surface of the waveguide sheet close to the first cover plate, that is, the acute angle formed between the hypotenuse and the base of the parallelogram. Compared with the rectangular grating, the diffraction efficiency of the inclined grating is higher.

[0049] In some embodiments of the present invention, the period of the inclined grating can be 200 nm to 500 nm, the height can be 50 nm to 500 nm, and the duty cycle can be 0.2 to 0.8. When the period, height, and / or duty cycle of the inclined grating are within the above ranges, it is beneficial to adjust the light, thereby facilitating the improvement of the display effect.

[0050] In some embodiments of the present invention, the etching of the inclined grating can be achieved by IBE (abbreviation for Ion Beam Etching, ion beam etching) and / or RIBE (abbreviation for Reactive Ion Beam Etching, reactive ion beam etching).

[0051] In still some other embodiments of the present invention, referring to Figure 6 , the grating 320 can be a blazed grating. The longitudinal cross-section of the blazed grating can be a triangle, and the inclination angle of the grating 320 (the acute angle formed between the base of the triangle and the other two sides) can be 30° to 80°. For example, the inclination angle of the grating 320 can be 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, etc. In the blazed grating, the acute angles formed between the two side surfaces of the grating and the surface of the waveguide sheet close to the first cover plate can both be within the range of 30° to 80°. Compared with the rectangular grating, the diffraction efficiency of the blazed grating is higher, and the blazed grating can also be used as a reflective grating.

[0052] In some embodiments of the present invention, referring to Figure 6 and Figure 10 , the period b of the blazed grating can be 200 nm to 500 nm, the height h of the blazed grating can be 50 nm to 500 nm, and the duty cycle (a / b) of the blazed grating can be 0.2 to 0.8. When the period, height, and / or duty cycle of the blazed grating are within the above ranges, it is beneficial to adjust the propagation path of light, thereby facilitating the improvement of the display effect and the user experience.

[0053] In some embodiments of the present invention, the topography of the blazed grating can be achieved by grayscale exposure or IBE.

[0054] In still other embodiments of the present invention, referring to Figure 7 , the grating 320 can be a metasurface grating, the period of the metasurface grating can be gradually changed, and the duty cycle can also be gradually changed. By using a metasurface grating for the grating in the optical waveguide component, purposes such as improving uniformity and enhancing optical efficiency can be achieved.

[0055] In an embodiment of the present invention, referring to Figure 7 , the period of the metasurface grating can be 200 nm to 500 nm, the height can be 50 nm to 500 nm, and the gradually changing duty cycle of the metasurface grating can be 0.2 to 0.8. When the period, height, and / or duty cycle of the metasurface grating are within the above ranges, it is beneficial to adjust the propagation path of light.

[0056] In some embodiments of the present invention, the metasurface grating can be a transmissive structure or a geometric structure, or a composite structure of both the transmissive structure and the geometric structure.

[0057] In some embodiments of the present invention, referring to Figures 2 to 7 , the optical waveguide component may further include a second cover plate 500. The second cover plate 500 is located on the side of the optical waveguide layer 300 farthest from the first cover plate 100 and away from the first cover plate 100. The second cover plate 500 and the optical waveguide layer 300 farthest from the first cover plate 100 are bonded through a third adhesive layer 600. The second cover plate can play a role in protecting the optical waveguide layer. By using an entire layer of the third adhesive layer to bond the second cover plate and the optical waveguide layer adjacent to the second cover plate, the third adhesive layer can also serve as a stress point, thereby further improving the drop resistance of the optical waveguide component.

[0058] In some embodiments of the present invention, the material of the first cover plate and the material of the second cover plate can independently include glass, PET (polyethylene terephthalate), or PI (polyimide). The above materials have certain support performance and can provide a certain support for the film layers thereon. Moreover, the above materials all have good light transmittance, which is beneficial to improving the display effect.

[0059] In some embodiments of the present invention, the material of the first cover plate and the material of the second cover plate can be the same. For example, the materials of the first cover plate and the second cover plate can both be glass, PET, or PI.

[0060] In some embodiments of the present invention, the materials of the first cover plate and the second cover plate may be different. For example, the materials of the first cover plate and the second cover plate may be glass and PET respectively, or the materials of the first cover plate and the second cover plate may be PET and glass respectively, or the materials of the first cover plate and the second cover plate may be PET and PI respectively, or the materials of the first cover plate and the second cover plate may be PI and glass respectively.

[0061] In some embodiments of the present invention, the materials of the first adhesive layer, the second adhesive layer, and the third adhesive layer and the flat layer may be the same or different. In some specific embodiments of the present invention, the materials of the first adhesive layer, the second adhesive layer, and the third adhesive layer are the same as the material of the flat layer, and may all be UV glue.

[0062] In some embodiments of the present invention, referring to Figure 11 and Figure 12 , a grating 320 (nano-grating layer) can be formed on the waveguide sheet 310 by using nanoimprint technology first, and then, a flat layer 330 is formed. In some embodiments of the present invention, the flat layer 330 can be formed by coating and curing UV glue on one side surface of the waveguide sheet 310 provided with the grating 320 to obtain the optical waveguide layer 300. Regarding the specific conditions for curing the UV glue, no special limitation is made in the present invention, and those skilled in the art can set them according to the actual situation.

[0063] In some specific embodiments of the present invention, referring to Figure 11 , after the flat layer 330 is formed, the optical waveguide layer 300 is bonded to the first cover plate 100 through the first adhesive layer 200 to obtain an optical waveguide assembly having one optical waveguide layer 300.

[0064] In some other specific embodiments of the present invention, referring to Figure 12 , after the flat layer 330 is formed, multiple optical waveguide layers 300 can be bonded through the second adhesive layer 400. Figure 12 Among the three optical waveguide layers 300 in

[0065] In another aspect of the present invention, the present invention provides an augmented reality display device. In some embodiments of the present invention, with reference to Figures 13 to 15 , the augmented reality display device may include a micro display 2000, a collimation component 3000, and the aforementioned optical waveguide component. Thus, the augmented reality display device has all the features and advantages of the aforementioned optical waveguide component. Generally speaking, the augmented reality display device has good overall stability, good drop resistance, and excellent display effects.

[0066] In some embodiments of the present invention, the collimation component 3000 may be a collimation lens. In other embodiments of the present invention, the collimation component 3000 may be a collimation lens group, which may include multiple collimation lenses.

[0067] In an embodiment of the present invention, with reference to Figures 13 to 15 , each optical waveguide layer 300 has a plurality of coupling gratings 321 and a plurality of output gratings 322. The basic principle of the augmented reality display device is that the micro display 2000 outputs the required virtual image information, and the collimation component 3000 collimates this image information, converting the light rays at each field of view angle into parallel light. The light rays enter the optical waveguide layer 300 through the coupling grating 321 of the optical waveguide layer 300, changing the light propagation direction. The parallel light at each field of view angle satisfies the total reflection condition in the optical waveguide layer, and the light rays propagate horizontally along the waveguide and reach the output grating 322. The output grating 322 also changes the light propagation direction, so that the light rays no longer satisfy the total internal reflection condition in the waveguide, exit from the waveguide, the light beam expands along the propagation direction, and enters the observer's eyes after being coupled out from the waveguide sheet 310, achieving the purpose of exit pupil expansion.

[0068] According to the embodiments of the present invention, there are no special requirements for the specific type of the above-mentioned augmented reality display device, and those skilled in the art can flexibly select according to actual needs. For example, it can be an augmented reality display device such as an AR glasses or an AR display helmet. Those skilled in the art can understand that in addition to the aforementioned optical waveguide component, micro display, and collimation component, the augmented reality display device may also have the structures and components necessary for a conventional display device (for example, a housing, etc.).

[0069] The terms "first", "second", and "third" in the text are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", and "third" may explicitly or implicitly include one or more of such features. In the description of the present invention, the meaning of "a plurality" is two or more, unless otherwise specifically defined.

[0070] In the description of this specification, the descriptions referring to terms such as "one embodiment", "another embodiment", "some embodiments", "some specific embodiments" or "some other specific embodiments" etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0071] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An optical waveguide component, characterized in that, Comprising a first cover plate, a first adhesive layer, and at least one optical waveguide layer, wherein the first adhesive layer bonds the first cover plate and one of the optical waveguide layers. The optical waveguide layer comprises a waveguide sheet, a grating, and a flat layer. The grating is located on the surface of the waveguide sheet close to the first cover plate. The grating comprises an input grating and an output grating. The flat layer fills the space defined by the grating and the waveguide sheet. The height of the flat layer is greater than or equal to the height of the grating. The refractive index of the grating is greater than the refractive index of the flat layer, and the difference between the refractive index of the grating and the refractive index of the flat layer is ≥ 0.

7.

2. The optical waveguide component according to claim 1, characterized in that, Comprising at least two optical waveguide layers, and adjacent optical waveguide layers are bonded by a second adhesive layer.

3. The optical waveguide component according to claim 1, wherein The number of the optical waveguide layers is 1, 2, or 3.

4. The optical waveguide component according to any one of claims 1 to 3, characterized in that The refractive index of the grating is ≥ 2.3, and the refractive index of the flat layer is 1.1 - 1.

3.

5. The optical waveguide component according to any one of claims 1 to 3, characterized in that The material of the grating comprises gallium nitride, the material of the waveguide sheet comprises gallium nitride, and the material of the flat layer comprises UV glue.

6. The optical waveguide component according to any one of claims 1 to 3, characterized in that, The grating satisfies at least one of the following conditions: The period of the grating is 200 nm - 500 nm; The height of the grating is 50 nm - 500 nm; The duty cycle of the grating is 0.2 - 0.

8.

7. The optical waveguide component according to any one of claims 1 to 3, characterized in that, The grating satisfies one of the following conditions: The grating is a rectangular grating; The grating is an inclined grating, and the inclination angle of the grating is 30° - 80°; The grating is a blazed grating, and the inclination angle of the grating is 30° - 80°; The grating is a metasurface grating.

8. The optical waveguide component according to any one of claims 1 to 3, characterized in that, Further comprising a second cover plate, which is located on the side of the optical waveguide layer farthest from the first cover plate and away from the first cover plate. The second cover plate is bonded to the optical waveguide layer farthest from the first cover plate by a third adhesive layer.

9. The optical waveguide component according to claim 8, wherein The material of the first cover plate and the material of the second cover plate independently comprise glass, PET, or PI.

10. An augmented reality display device, characterized in that, Comprising a microdisplay, a collimating component, and the optical waveguide component according to any one of claims 1 - 9.

Images