A multi-layer waveguide system and near-eye display device
By designing a multi-layer waveguide system and utilizing alternating stacked waveguide sheets and mirror structures, the problem of low optical energy utilization in single-layer array optical waveguides was solved, achieving efficient transmission and utilization of optical energy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- LINGXI-AR TECHNOLOGY CO LTD
- Filing Date
- 2025-04-03
- Publication Date
- 2026-06-12
AI Technical Summary
Traditional single-layer array optical waveguide structures suffer from low optical energy utilization.
A multi-layer waveguide system is used, which uses alternating layers of first and second waveguide sheets and low-refractive-index film layers between adjacent sheets, combined with the symmetrical arrangement of mirrors, to achieve multiple reflections and transmission of light within the waveguide.
It effectively improves the utilization rate of light energy, has a simple structure, is easy to manufacture, and significantly improves the utilization rate of light energy.
Smart Images
Figure CN224354604U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of augmented reality technology, and in particular to a multilayer waveguide system and a near-eye display device. Background Technology
[0002] Head-mounted displays for augmented reality use near-eye display technology, allowing people to view virtual images projected onto the real world they perceive while looking at their surroundings. This creates a more realistic experience and enhances user immersion.
[0003] Based on the coupling and elution methods of light, optical waveguide schemes can be divided into two main categories: arrayed waveguides and diffractive waveguides. Compared to diffractive waveguides, arrayed waveguides mainly rely on geometric optics principles, transmitting images through the reflection and refraction of light. Therefore, arrayed waveguides do not introduce additional dispersion into the image, and their light energy utilization is very high. However, in traditional single-layer arrayed waveguide structures, some light rays are coupled out through the coupling structure, while the remaining light rays are wasted, resulting in low light energy utilization. Utility Model Content
[0004] In view of the problems existing in the prior art, this utility model provides a multi-layer waveguide system and a near-eye display device, which improves the light energy utilization rate by combining the multi-layer waveguide structure with the setting of reflectors.
[0005] The technical solution of this utility model is as follows:
[0006] This application provides a multilayer waveguide system, including:
[0007] Multiple first waveguide sheets, including a first coupling end and a first coupling end, a first coupling structure is provided near the first coupling end, the first coupling structure includes multiple first beam splitting surfaces that are inclined along a first direction and arranged at equal intervals; a first reflector is provided near the first coupling end, and / or a first reflector is provided between the first coupling end and the first coupling structure;
[0008] Multiple second waveguide sheets, including a second coupling end and a second coupling end, a second coupling structure is provided near the second coupling end, the second coupling structure includes multiple second beam splitting surfaces that are inclined along a second direction and arranged at equal intervals; a second reflector is provided near the second coupling end, and / or a second reflector is provided between the second coupling end and the second coupling structure;
[0009] The first waveguide sheet and the second waveguide sheet are alternately stacked. The first reflector located near the first coupling end and the second reflector located near the second coupling end are symmetrically arranged, and / or the first reflector located between the first coupling end and the first coupling structure and the second reflector located between the second coupling end and the second coupling structure are symmetrically arranged. The first reflector is configured such that a portion of the light propagating in the first waveguide sheet is reflected by the first reflector into the next second light guide sheet. The second reflector is configured such that a portion of the light propagating in the second waveguide sheet is reflected by the second reflector into the next first light guide sheet. The first direction and the second direction are opposite.
[0010] A low-refractive-index film is disposed between adjacent first and second waveguide sheets.
[0011] As a preferred technical solution, it also includes a coupling prism, with the first waveguide sheet and the second waveguide sheet alternately stacked, and the first waveguide sheet located on the outermost layer, and the coupling prism located at the first coupling end.
[0012] As a preferred technical solution, the coupling prism is a right-angled triangular prism, and the inclined surface of the right-angled triangular prism forms an angle α with the first direction.
[0013] As a preferred technical solution, the first beam-splitting surface forms an angle with the first direction. The second beam-splitting surface forms an angle with the second direction. Among them, the included angle α and the included angle β are the same or different, and the interval between adjacent first beam-splitting surfaces is the same or different from the interval between adjacent second beam-splitting surfaces.
[0014] As a preferred technical solution, the angle between the first reflecting mirror and the second direction is... The angle between the second reflecting mirror and the first direction is
[0015] As a preferred technical solution, both the first and second reflecting mirrors are total reflection mirrors.
[0016] As a preferred technical solution, the reflectivity of both the first and second beam-splitting surfaces is 5%-10%.
[0017] As a preferred technical solution, the reflectivity of the first beam-splitting surface and the second beam-splitting surface may be the same or different.
[0018] As a preferred technical solution, the low refractive index film layer has a thickness of 100nm-1um.
[0019] This application also provides a near-eye display device, including the aforementioned multilayer waveguide system.
[0020] The beneficial effects achieved by the technical solution adopted in this utility model are as follows:
[0021] This application provides a multilayer waveguide system and a near-eye display device. The system includes multiple first waveguide sheets and multiple second waveguide sheets stacked alternately. A low-refractive-index film layer is located between adjacent first and second waveguide sheets. The first coupling end of the first waveguide sheet corresponds to the second coupling end of the second waveguide sheet, and the first coupling structure corresponds to the second coupling structure. A first reflector located near the first coupling end and a second reflector located near the second coupling end are symmetrically arranged, and / or the first reflector located between the first coupling end and the first coupling structure is symmetrically arranged with the second reflector located between the second coupling end and the second coupling structure. This system is used to transmit the remaining light transmitted in the waveguide to the next waveguide. The system has a simple structure, is easy to manufacture, and effectively improves the light energy utilization rate. Attached Figure Description
[0022] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below, forming part of this utility model. The illustrative embodiments of this utility model and their descriptions explain this utility model and do not constitute an improper limitation of this utility model. In the accompanying drawings:
[0023] Figure 1 This is a schematic diagram of the multilayer waveguide system structure disclosed in this embodiment;
[0024] Figure 2 This is a schematic diagram of the multilayer waveguide system structure disclosed in this embodiment;
[0025] Figure 3 This is a schematic diagram of the multilayer waveguide system structure disclosed in this embodiment.
[0026] Explanation of reference numerals in the attached figures:
[0027] Coupled-in prism 10; first waveguide 20; first coupling-out structure 21; first reflector 22; second waveguide 30; second coupling-out structure 31; second reflector 32; low refractive index film 40. Detailed Implementation
[0028] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. In the description of this utility model, it should be noted that the term "or" is generally used to include the meaning of "and / or," unless otherwise expressly stated otherwise.
[0029] In the description of this utility model, it should be understood that terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, terms such as "connected" and "linked" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through a medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0030] Furthermore, those skilled in the art should understand that in the disclosure of this utility model, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limitations on this utility model.
[0031] Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0032] Example
[0033] Given the low optical energy utilization of traditional single-layer arrayed optical waveguides, based on Figures 1-3 This embodiment provides a multilayer waveguide system, including:
[0034] Multiple first waveguide sheets 20, including a first coupling end and a first coupling end, a first coupling structure 21 is provided near the first coupling end, the first coupling structure 21 includes multiple first beam splitting surfaces that are inclined along a first direction and arranged at equal intervals; a first reflector 22 is provided near the first coupling end, and / or a first reflector 22 is provided between the first coupling end and the first coupling structure 21.
[0035] Multiple second waveguide sheets 30, including a second coupling end and a second coupling end, a second coupling structure 31 is provided near the second coupling end, the second coupling structure 31 includes multiple second beam splitting surfaces that are inclined along the second direction and arranged at equal intervals; a second reflector 32 is provided near the second coupling end, and / or a second reflector 32 is provided between the second coupling end and the second coupling structure 31.
[0036] The first waveguide sheet 20 and the second waveguide sheet 30 are alternately stacked. The first reflector 22 near the first coupling end and the second reflector 32 near the second coupling end are symmetrically arranged, and / or the first reflector 22 between the first coupling end and the first coupling structure 21 and the second reflector 32 between the second coupling end and the second coupling structure 31 are symmetrically arranged. The first reflector 22 is configured such that a portion of the light propagating in the first waveguide sheet 20 is reflected by the first reflector 22 into the next second light guide sheet. The second reflector 32 is configured such that a portion of the light propagating in the second waveguide sheet 30 is reflected by the second reflector 32 into the next first light guide sheet. The first direction and the second direction are opposite.
[0037] A low-refractive-index film layer 40 is disposed between adjacent first waveguide sheet 20 and second waveguide sheet 30.
[0038] The multilayer waveguide system provided in this embodiment includes multiple first waveguide sheets 20 and multiple second waveguide sheets 30 alternately stacked. A low-refractive-index film layer 40 is located between the first waveguide sheets 20 and the second waveguide sheets 30. The first coupling end of the first waveguide sheet 20 is correspondingly arranged with the second coupling end of the second waveguide sheet 30. The first coupling structure 21 is correspondingly arranged with the second coupling structure 31. The first reflector 22 located near the first coupling end is symmetrically arranged with the second reflector 32 located near the second coupling end. And / or the first reflector 22 located between the first coupling end and the first coupling structure 21 is symmetrically arranged with the second reflector 32 located between the second coupling end and the second coupling structure 31. This system is used to transmit the remaining light transmitted in the waveguide to the next waveguide. The structure is simple, easy to manufacture, and effectively improves the light energy utilization rate.
[0039] Specifically, a multilayer waveguide system refers to a system with at least two or more waveguide sheets stacked together. This can be understood as follows: for example, a first waveguide sheet 20 and a second waveguide sheet 30 are stacked together to form a two-layer waveguide system; or two first waveguide sheets 20 and a second waveguide sheet 30 are stacked together, with the second waveguide sheet 30 located between the two first waveguide sheets 20, forming a three-layer waveguide system. Similarly, multiple first waveguide sheets 20 and multiple second waveguide sheets 30 are stacked together to form a multilayer waveguide system. Regardless of the number of layers, the first waveguide sheet 20 is located on the outermost layer and is used to place the coupling prism 10 at its coupling end, facilitating the coupling of light into the waveguide system. This embodiment uses a two-layer waveguide system as an example for description.
[0040] according to Figures 1-2The dual-layer waveguide system includes a first waveguide sheet 20 and a second waveguide sheet 30. A low-refractive-index film layer 40 is disposed between the first waveguide sheet 20 and the second waveguide sheet 30. Both the first waveguide sheet 20 and the second waveguide sheet 30 include an upper substrate and a lower substrate that are parallel to each other. In this embodiment, at least a coupling structure and a reflector are disposed between the upper substrate and the lower substrate. The upper substrate, the lower substrate, the first beam splitter, and the second beam splitter are preferably made of glass, which helps to stabilize light transmission. The first waveguide sheet 20 includes a first coupling end and a first coupling end, and the second waveguide sheet 30 includes a second coupling end and a second coupling end. Preferably, it also includes a coupling prism 10. The first waveguide sheet 20 and the second waveguide sheet 30 are stacked, with the first waveguide sheet 20 located on the outermost layer. A low-refractive-index film layer 40 is disposed between the first waveguide sheet 20 and the second waveguide sheet 30. The coupling prism 10 is disposed at the first coupling end to couple the virtual image into the first waveguide for total internal reflection transmission. In a preferred embodiment, the coupling prism 10 is a right-angled triangular prism, and the inclined surface of the right-angled triangular prism forms an angle α with the first direction, so that the incident light can be completely coupled into the first waveguide plate 20, thereby improving the light utilization rate.
[0041] Furthermore, the first waveguide 20 includes at least a first coupling structure 21 disposed near the first coupling end. The first coupling structure 21 includes a first beam-splitting array, which includes a plurality of parallel and equally spaced first beam-splitting surfaces. The plurality of first beam-splitting surfaces are arranged along a first direction and at an angle. The second waveguide 30 is configured to include at least a second coupling structure 31 near the second coupling end. The second coupling structure 31 includes a second beam-splitting array, which comprises multiple parallel and equally spaced second beam-splitting surfaces. These multiple second beam-splitting surfaces are arranged along a second direction and at an angle. The first coupling structure 21 and the second coupling structure 31 are both used to couple virtual image light to the human eye. The included angle α and included angle β may be the same or different, which can be understood as the tilt angle α and tilt angle β being the same or different. The interval between adjacent first beam splitters and adjacent second beam splitters may be the same or different, which can be understood as the interval between adjacent first beam splitters and adjacent second beam splitters being the same or different. The number of first beam splitters and the number of second beam splitters may be the same or different, which can be understood as the number of first beam splitters and the number of second beam splitters being the same, for example, both being 7; or the number of first beam splitters and the number of second beam splitters being different, for example, the number of first beam splitters being 7 and the number of second beam splitters being 6, or the number of first beam splitters being 5 and the number of second beam splitters being 7. The specific number is selected according to actual needs and is not specifically limited here. Preferably, both tilt angle α and tilt angle β are 60°, the interval between adjacent first beam splitting surfaces is the same as the interval between adjacent second beam splitting surfaces, and the number of first beam splitting surfaces is the same as the number of second beam splitting surfaces, which can effectively improve the uniformity of the coupled light.
[0042] In a preferred embodiment, to ensure that the central ray of the virtual image enters the human eye perpendicularly, the tilt angle of the first beam-splitting surface is equal to the tilt angle of the first reflecting mirror 22. The spacing between the first beam splitter planes is The tilt angle of the second beam-splitting surface is equal to the tilt angle of the second reflecting mirror 32. The spacing between adjacent second beam-splitting surfaces is Wherein, d1 is the thickness of the first waveguide plate 20, and d2 is the thickness of the second waveguide plate 30.
[0043] Furthermore, since a coupling prism 10 is provided at the first coupling end of the first waveguide 20, and it is a double-layer waveguide system, preferably, for the first waveguide 20, a first reflector 22 is provided between the first coupling end and the first coupling structure 21, and for the second waveguide 30, a second reflector 32 is provided between the second coupling end and the second coupling structure 31, with the first reflector 22 and the second reflector 32 arranged symmetrically; according to Figure 3If it is a three-layer waveguide system, since a coupling prism 10 is set at the first coupling end of the first waveguide sheet 20, and it is a three-layer waveguide system, for the first waveguide sheet 20, a first reflector 22 is set between the first coupling end and the first coupling structure 21. For the second waveguide sheet 30, a second reflector 32 is set between the second coupling end and the second coupling structure 31, and a second reflector 32 is set near the second coupling end. For the third layer, i.e., the first waveguide sheet 20, it can be understood that the next layer is also a first waveguide sheet 20, and a first reflector 22 is set between the first coupling end and the first coupling structure 21. For the entire three-layer waveguide system, the first reflector 22 in the first waveguide sheet 20 and the second reflector 32 in the second waveguide sheet 30 at the coupling end of the system are symmetrically arranged. The symmetrical arrangement of the second reflector 32 in the second waveguide sheet 30 is symmetrical with the symmetrical arrangement of the first reflector 22 in the first waveguide sheet 20 of the next layer. Preferably, the angle between the first reflector 22 and the second direction is . The angle between the second reflecting mirror 32 and the first direction is Furthermore, both the first reflecting mirror 22 and the second reflecting mirror 32 are total reflection mirrors, which result in more uniform light output and a significant improvement in light energy utilization.
[0044] Preferably, the reflectivity of both the first beam-splitting surface and the second beam-splitting surface is 5%-10%. The reflectivity of the first beam-splitting surface and the second beam-splitting surface can be the same or different to ensure the uniformity of light output. In a preferred embodiment, the reflectivity of the first beam-splitting surface and the second beam-splitting surface is the same, resulting in better overall uniformity of light output.
[0045] Furthermore, a low-refractive-index film layer 40 is disposed between the first waveguide 20 and the second waveguide 30 to separate the first waveguide 20 and the second waveguide 30, and to restrict light to transmit independently by total internal reflection within the first waveguide 20 and the second waveguide 30 without crosstalk. In actual processing, the low-refractive-index film layer 40 is prepared on the bonding surface of the first waveguide 20 by optical coating, and then bonded to the bonding surface of the second waveguide 30 by bonding. Alternatively, the bonding can be achieved by optical coating. The surface is prepared on the bonding surface of the second waveguide sheet 30, and then bonded to the bonding surface of the first waveguide sheet 20 by bonding method, or by other glue-free process to bond the first waveguide sheet and the second waveguide sheet together. Preferably, the low refractive index film 40 is a magnesium fluoride film or a silicon dioxide film, and the thickness of the low refractive index film 40 is 100nm-1um. The specific material and thickness of the low refractive index film 40 and other requirements can be set by those skilled in the art according to the actual needs of this solution, and are not specifically limited here.
[0046] according to Figure 2An optical path diagram for improving the light energy utilization of a two-layer waveguide system is provided. Initially, the coupled light is coupled into the first waveguide plate 20 by the coupling prism 10 for total internal reflection. Part of the light is coupled out of the first waveguide plate 20 by the first coupling structure 21. The remaining light continues to propagate forward within the first waveguide plate 20 and is then reflected by the first reflecting mirror 22 into the second waveguide plate 30. Further, part of the remaining light is coupled out of the waveguide system again by the second coupling structure 31. Finally, the remaining light is absorbed by the sidewall of the second waveguide plate 30. Similarly, the scheme of this application is also applicable to multi-layer waveguide systems such as three-layer and four-layer waveguide systems.
[0047] This embodiment also provides a near-eye display device, including the above-mentioned multilayer waveguide system, which has a simple structure and effectively improves light energy utilization.
[0048] The foregoing has provided a detailed description of a multilayer waveguide system and a near-eye display device according to embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A multilayer waveguide system, characterized in that, include: Multiple first waveguide sheets, including a first coupling end and a first coupling end, are provided with a first coupling structure near the first coupling end. The first coupling structure includes multiple first beam-splitting surfaces that are inclined along a first direction and arranged at equal intervals. A first reflector is provided near the first coupling end, and / or a first reflector is provided between the first coupling end and the first coupling structure; Multiple second waveguide sheets, including a second coupling end and a second coupling end, are provided with a second coupling structure near the second coupling end. The second coupling structure includes multiple second beam-splitting surfaces that are inclined along a second direction and arranged at equal intervals. A second reflector is provided near the second coupling in end, and / or a second reflector is provided between the second coupling out end and the second coupling out structure; The first waveguide sheet and the second waveguide sheet are alternately stacked. The first reflector located near the first coupling end and the second reflector located near the second coupling end are symmetrically arranged, and / or the first reflector located between the first coupling end and the first coupling structure and the second reflector located between the second coupling end and the second coupling structure are symmetrically arranged. The first reflector is configured such that a portion of the light propagating in the first waveguide sheet is reflected by the first reflector into the next second waveguide sheet. The second reflector is configured such that a portion of the light propagating in the second waveguide sheet is reflected by the second reflector into the next first waveguide sheet. The first direction and the second direction are opposite. A low-refractive-index film is disposed between adjacent first waveguide sheets and second waveguide sheets.
2. The multilayer waveguide system according to claim 1, characterized in that, It also includes a coupling prism, wherein the first waveguide sheet and the second waveguide sheet are alternately stacked, and the first waveguide sheet is located on the outermost layer, and the coupling prism is located at the first coupling end.
3. The multilayer waveguide system according to claim 2, characterized in that, The coupling prism is a right-angled triangular prism, and the inclined face of the right-angled triangular prism forms an angle with the first direction. α。 4. The multilayer waveguide system according to claim 3, characterized in that, The first beam-splitting surface forms an angle with the first direction. The second beam-splitting surface forms an angle with the second direction. ， Wherein, the included angle α With the included angle β The spacing between adjacent first beam-splitting surfaces may be the same or different from the spacing between adjacent second beam-splitting surfaces.
5. The multilayer waveguide system according to claim 4, characterized in that, The angle between the first reflector and the second direction is The angle between the second reflector and the first direction is... .
6. The multilayer waveguide system according to claim 5, characterized in that, Both the first and second reflectors are total reflection mirrors.
7. The multilayer waveguide system according to claim 6, characterized in that, The reflectivity of both the first and second beam-splitting surfaces is 5%-10%.
8. The multilayer waveguide system according to claim 7, characterized in that, The reflectivity of the first beam-splitting surface and the second beam-splitting surface may be the same or different.
9. The multilayer waveguide system according to any one of claims 1-8, characterized in that, The low refractive index film is a magnesium fluoride film or a silicon dioxide film, and the thickness of the low refractive index film is 100 nm-1 μm.
10. A near-eye display device, characterized in that, Includes the multilayer waveguide system as described in any one of claims 1-9.