Diopter correction waveguide structure and intelligent glasses
By introducing an off-axis mirror array and a parabolic freeform surface into the optical waveguide structure, the problem of nearsighted users needing to wear glasses is solved, enabling clear viewing of virtual images without glasses, thus improving user experience and comfort.
Patent Information
- Application Number
- CN202423185768.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-23
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2034-12-23
AI Technical Summary
Existing optical waveguide structures require nearsighted users to wear glasses to view virtual images clearly, affecting aesthetics and comfort, and reducing the viewing experience.
An off-axis mirror array is used instead of a traditional beam splitter array. The transmittance-to-reflection ratio and arrangement of the off-axis mirrors are reasonably set, and combined with a parabolic freeform surface and an optical beam splitter, a refractive power correction waveguide structure is formed.
This allows nearsighted users to clearly observe virtual images without wearing their glasses, improving the user experience and comfort.
Smart Images
Figure CN223501197U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of augmented reality technology, and in particular to a refractive correction waveguide structure and smart glasses. Background Technology
[0002] In recent years, Augmented Reality (AR) technology has developed rapidly, with a series of related commercial products being released, such as Google Glass, Epson's BT-40, Microsoft HoloLens 2, and AR glasses from Vivo and Xiaomi. This technology overlays virtual images onto the user's perceived real world, creating a realistic experience and showing great promise in military, security, industrial, and medical fields. To achieve the functions of augmented reality, researchers have proposed various solutions, such as Birdbath, prisms, freeform surfaces, and optical waveguides. Among the first three solutions, a good product form and superior display effect often present a trade-off, while optical waveguides can effectively solve these problems.
[0003] Optical waveguides can be classified into diffraction waveguides (DWGs) and reflective waveguides (RWGs) based on their coupling optics. Diffraction waveguides expand the exit pupil of incident light by using a grating structure etched on the waveguide surface, while reflective waveguides expand the exit pupil of incident light using a partial mirror array based on geometric optics principles.
[0004] Based on the dimension of exit pupil expansion, optical waveguides can be divided into one-dimensional optical waveguides (1D-WGSs) and two-dimensional optical waveguides (2D-WGSs). Compared to 1D-WGS, whose exit pupil expands only in the horizontal or vertical direction, 2D-WGS expands in both directions. Therefore, 2D-WGS can achieve better imaging results with a more compact volume.
[0005] Regardless of the type of optical waveguide, the waveguide itself can be equivalent to a parallel plate. In practical use, it is necessary to satisfy parallel light incidence, parallel light transmission, and parallel light coupling. Therefore, for users with nearsightedness or farsightedness, especially those with nearsightedness, they still need to wear nearsighted glasses when observing images at infinity coupled from the waveguide. In this case, it increases the inconvenience of wearing glasses, affects the overall aesthetics and comfort, and reduces the viewing experience. Utility Model Content
[0006] In view of the problems existing in the prior art, this utility model provides a refractive correction waveguide structure and smart glasses.
[0007] The technical solution of this utility model is as follows:
[0008] This application provides a refractive correction waveguide structure, including:
[0009] The waveguide body includes at least an input portion for receiving the light beam and an output pupil portion for emitting the light beam. The output pupil portion is an off-axis mirror array. The off-axis mirrors in the off-axis mirror array are arranged periodically. Each off-axis mirror is a rectangular cube. The off-axis mirror includes an off-axis freeform surface, which is parallel to the surface of the waveguide body. The off-axis freeform surface is provided with an optical beam splitter.
[0010] As a preferred technical solution, the off-axis freeform surface is a parabola, and the curvature curve of the parabola can be represented by a parabolic function.
[0011] As a preferred technical solution, the optical beam splitter is located at 1 / 2 of the height of the off-axis mirror.
[0012] As a preferred technical solution, the optical beam splitter is connected to the off-axis freeform surface by adhesive bonding or bonding.
[0013] As a preferred technical solution, the transmittance-to-reflection ratio of the optical beam splitter of each off-axis mirror is the same or different.
[0014] As a preferred technical solution, the reflectivity of the optical beam splitter is 5%-20%.
[0015] As a preferred technical solution, each off-axis mirror is arranged closely without any gaps, or adjacent off-axis mirrors are arranged with a gap of no more than 1 / 10 of the height of the off-axis mirror.
[0016] As a preferred technical solution, it also includes a turning pupil expansion section, which is a beam splitting film array. The beam splitting film array is disposed in the waveguide body and is adjacent to the coupling section, so that the light enters the turning pupil expansion section through the coupling section, turns, and then enters the coupling pupil expansion section.
[0017] As a preferred technical solution, the coupling part is a prism or a reflector, which is set on the waveguide body and near the turning pupil part to couple the incident light into the waveguide body.
[0018] This application also provides a smart glasses, including the aforementioned diopter-correcting waveguide structure.
[0019] The beneficial effects achieved by the technical solution adopted in this utility model are as follows: This application proposes a refractive correction waveguide structure and smart glasses. This structure introduces an off-axis reflector array to replace the traditional beam splitter array coupling structure. By reasonably setting the transmittance-to-reflection ratio and arrangement of the off-axis reflectors, the presence of the off-axis reflector array causes parallel light to no longer be parallel light after reflection, but to have a certain divergence angle. This structure not only has the advantages of a reflective waveguide, but also enables myopic users to clearly observe the virtual image displayed on the waveguide without wearing myopic glasses, greatly enhancing the user experience. Attached Figure Description
[0020] 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:
[0021] Figure 1 This is a schematic diagram of the refractive correction waveguide structure disclosed in this embodiment;
[0022] Figure 2 This is a schematic diagram of the refractive correction waveguide structure disclosed in this embodiment;
[0023] Figure 3 This is a schematic diagram of the refractive correction waveguide structure disclosed in this embodiment;
[0024] Figure 4 This is a schematic diagram of the refractive correction waveguide structure disclosed in this embodiment.
[0025] Explanation of reference numerals in the attached figures:
[0026] The coupling-out pupil dilator 10; the off-axis reflecting mirror 11; the folding pupil dilator 20; and the coupling-in portion 30. Detailed Implementation
[0027] 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.
[0028] 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.
[0029] 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.
[0030] 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.
[0031] Example
[0032] Due to the existing optical principle of arrayed waveguides, light must undergo a series of total internal reflections on the front and back surfaces of the waveguide before finally exiting the eye through the coupling structure as parallel light. This requires nearsighted people to wear corrective glasses, resulting in poor visual experience and inconvenience.
[0033] In view of this, according to Figure 2 This embodiment provides a waveguide structure for refractive power correction, comprising:
[0034] The waveguide body includes at least an input portion 30 for receiving the light beam and an output pupil portion 10 for emitting the light beam. The output pupil portion 10 is an array of off-axis mirrors 11. The off-axis mirrors 11 in the array of off-axis mirrors 11 are arranged periodically. Each off-axis mirror 11 is rectangular or cubic in shape. The off-axis mirror 11 includes an off-axis freeform surface. The off-axis freeform surface is parallel to the surface of the waveguide body and is provided with an optical beam splitter.
[0035] This embodiment mainly replaces the traditional beam splitter array coupling structure by introducing an off-axis reflector array 11. By reasonably setting the transmittance-to-reflection ratio and arrangement of the off-axis reflectors 11, it not only has the advantages of a reflective waveguide, but also allows nearsighted users to clearly observe the virtual image displayed on the waveguide without wearing their glasses, greatly enhancing the user experience.
[0036] The waveguide body typically has a waveguide substrate, specifically an upper substrate and a lower substrate that are parallel to each other. The waveguide substrate material can be glass, resin, etc., with glass being preferred due to its low cost, ease of processing, and good optical properties. At least a coupling pupil portion 10 is included between the upper and lower substrates, such as in a common two-dimensional array waveguide. Figure 2 The waveguide substrate also includes a turning pupil expansion section 20, which is responsible for expanding the pupil in one dimension and then propagating the light to the coupling out pupil expansion section 10. The coupling out pupil expansion section 10 is responsible for expanding the pupil in another dimension and coupling out the light. The coupling in section 30, usually a prism, is set on the waveguide body and is used to couple the light emitted from the optical engine into the waveguide body.
[0037] Furthermore, the coupling pupil expansion section 10 employs an array of off-axis mirrors 11, with the off-axis mirrors 11 embedded within the waveguide body. The arrangement of the off-axis mirrors 11 is shown in Figure 1-. Figure 2 As shown, the reflectivity is between 5% and 20%, mainly used to couple the image light to the human eye and to enlarge the pupil in one dimension before coupling it to the human eye. At the same time, depending on the user's degree of myopia, the curvature of the off-axis mirror 11 can be set to achieve myopia correction according to actual needs.
[0038] Preferably, the optical beam-splitting film is connected to the off-axis freeform surface by adhesive bonding or bonding.
[0039] Specifically, according to Figure 3 It can be understood that each off-axis reflector 11 includes two parts, namely an upper part and a lower part, which are spliced together by gluing or bonding. The splicing surface is an off-axis surface, and the off-axis surface is a free-form surface. An optical beam splitting film is provided on the off-axis free-form surface. The free-form surface is approximately parallel to the upper substrate and / or lower substrate of the waveguide body.
[0040] Preferably, the optical beam splitter is located at 1 / 2 of the height of the off-axis mirror 11, which provides the best vision correction effect and effectively improves the user's image viewing experience. It can be understood that the common surface at the splicing point will divide the entire off-axis mirror 11 into two parts. In actual operation, the optical beam splitter is fixed to the off-axis freeform surface between the upper and lower parts by gluing or bonding, which has good light transmission efficiency.
[0041] Furthermore, the off-axis freeform surface can be a parabola, a hemisphere, etc., to restrict the direction of light propagation, and the selection is made according to actual needs. The shape of the optical beam splitter is preferably consistent with the off-axis freeform surface, so that the optical beam splitter and the off-axis reflector 11 can be integrated into one body and play a mutual cooperation role. It is also easy to process. Preferably, the reflectivity of the optical beam splitter is 5%-20%, which has the best vision correction effect. The specific transmittance-to-reflectance ratio can be set according to actual needs. Preferably, the off-axis freeform surface is a parabola. The arc curve of the parabola can be represented by a parabolic function, which can restrict the direction of light propagation, thereby reducing aberrations and focusing the image on one point, making it easier for the human eye to see a clear image.
[0042] Preferably, the optical beam splitter of each off-axis mirror 11 has the same or different transmittance-to-reflection ratios, which provides better imaging performance and can adapt to the different refractive power requirements of users.
[0043] Furthermore, see Figure 3 Each off-axis reflector 11 in the off-axis reflector array is preferably a rectangular cube. The rectangular cube method is simple, efficient, easy to implement, easy to operate, and has a wide range of applications. Preferably, each off-axis reflector 11 can be arranged closely without gaps, or adjacent off-axis reflectors can be arranged with a gap of no more than 1 / 10 of the height of the off-axis reflector. Both are arranged in a periodic matrix manner, which can reflect the image light from infinity and play a certain divergence role. Then the image light from infinity will be well focused on the retina, and the user can observe the image information more clearly.
[0044] Specifically, if each off-axis mirror 11 in the coupling pupil expansion section 10 is identical, including its shape (all freeform surfaces are parabolic) and the reflectivity of the optical beam splitter is the same, then each off-axis mirror 11 will have the same effect on light rays at infinity. Figure 4 The dashed line depicts the optical path when a nearsighted user views a traditional waveguide display image. It shows that, due to the degree of nearsightedness, the light rays from the image at infinity cannot converge onto the retina, but instead focus on the nearsighted image point in front of the retina, resulting in a blurred image. The solid line depicts the optical path when a nearsighted user views the waveguide display image proposed in this paper. It shows that, due to the presence of the off-axis mirror array 11, parallel light, after being reflected, is no longer parallel but has a certain divergence angle. That is, the image at infinity is imaged to a finite distance. Therefore, the light rays after passing through the off-axis mirror 11 converge onto the retina after passing through the human eye, allowing the user to clearly observe the real image. In this process, the off-axis mirror 11 acts similarly to nearsighted glasses.
[0045] In the above process, the upper and lower parts of the off-axis reflector 11 are preferably made of the same material and the same material as the waveguide body, such as glass. It is preferable that multiple off-axis reflectors 11 are closely arranged and attached together to form an off-axis reflector 11 array. This will not change the propagation direction of the parallel light in the waveguide until it encounters the next off-axis reflector 11 and is reflected out of the waveguide and enters the human eye.
[0046] Furthermore, see Figure 2 The waveguide body also includes a coupling section 30 and a turning pupil expansion section 20. The turning pupil expansion section 20 is specifically a beam splitter array, with multiple beam splitters arranged at equal intervals along the second dimension and at an angle, so that light rays enter through the coupling section 30, turn at the turning pupil expansion section 20, and then exit through the coupling pupil expansion section 10. The coupling section 30 is a prism or a mirror, preferably a right-angled triangular prism, which is placed on the waveguide body and adjacent to the turning pupil expansion section 20 to couple light rays into the waveguide body.
[0047] This embodiment also provides a smart glasses, including the waveguide structure described above, which is easy to wear, improves the viewing experience, and can meet the needs of users with different refractive errors.
[0048] The foregoing has provided a detailed description of a refractive correction waveguide structure and smart glasses 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 embodiments above 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 refractive power correction waveguide structure, characterized in that, include: The waveguide body includes at least an input portion for receiving the light beam and an output pupil portion for emitting the light beam. The output pupil portion is an off-axis mirror array. The off-axis mirrors in the off-axis mirror array are arranged periodically. Each off-axis mirror is rectangular or cubic in shape. Each off-axis mirror includes an off-axis freeform surface. The off-axis freeform surface is parallel to the surface of the waveguide body and is provided with an optical beam splitter.
2. The waveguide structure according to claim 1, characterized in that, The off-axis freeform surface is a parabola, and the arc curve of the parabola can be represented by a parabolic function.
3. The waveguide structure according to claim 2, characterized in that, The optical beam splitter is located at 1 / 2 of the height of the off-axis mirror.
4. The waveguide structure according to claim 3, characterized in that, The optical beam-splitting film is connected to the off-axis freeform surface by adhesive bonding or bonding.
5. The waveguide structure according to claim 4, characterized in that, The optical beam splitter of each of the off-axis mirrors may have the same or different transmittance-to-reflection ratios.
6. The waveguide structure according to claim 5, characterized in that, The reflectivity of the optical beam splitter is 5%-20%.
7. The waveguide structure according to claim 6, characterized in that, Each of the off-axis mirrors is arranged closely together without any gaps, or adjacent off-axis mirrors are arranged with a gap of no more than 1 / 10 of the height of the off-axis mirror.
8. The waveguide structure according to any one of claims 1-7, characterized in that, It also includes a deflection pupil expansion section, which is a beam splitter array disposed in the waveguide body and adjacent to the coupling section, so that light enters the deflection pupil expansion section through the coupling section, is deflected, and then incident on the coupling pupil expansion section.
9. The waveguide structure according to claim 8, characterized in that, The coupling portion is a prism or a reflector, which is disposed on the waveguide body and adjacent to the dilation pupil portion, to couple incident light into the waveguide body.
10. A type of smart glasses, characterized in that, Includes the waveguide structure described in any one of claims 1-9.