Optical-mechanical module and near-eye display device
By introducing afocal optical element into the optomechanical module and adjusting the matching between the exit pupil position and the waveguide coupling region, the problem of increased beam diffraction caused by the increased size of the coupling region is solved, thus improving the imaging quality and meeting the miniaturization requirements.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHENGDU IDEALSEE TECH
- Filing Date
- 2025-09-15
- Publication Date
- 2026-07-07
AI Technical Summary
In waveguide design, increasing the size of the coupling region leads to more secondary diffraction of the beam entering the coupling region, and the exit pupil position of the lens is difficult to coincide with the center region of the galvanometer, affecting the imaging quality of the optomechanical module.
By setting a focal-free optical element between the scanning unit and the waveguide, the exit pupil position of the optomechanical module is adjusted to match the coupling region of the waveguide, including the objective lens group and the eyepiece lens group. The optical path is adjusted using a negative refractive index flat plate lens to ensure that the beam size of the entire field of view is minimized when the light spot enters the coupling region.
This improves the imaging quality of the optomechanical module and ensures that the beam size is minimized across the entire field of view when the light spot is in the coupling region, meeting the requirements of miniaturized applications.
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Figure CN224471904U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of scanning display technology, specifically to an optomechanical module and a near-eye display device. Background Technology
[0002] Scanning display imaging, as an emerging display technology, can be used in various application scenarios such as projection display and near-eye display.
[0003] In waveguide design, an increase in the size of the coupling region will lead to an increase in secondary diffraction of the light beam entering the coupling region. Therefore, the light spots incident on the waveguide coupling region need to overlap as much as possible, and the size of the coupling region should be small enough while ensuring assembly tolerance.
[0004] Based on this, this specification provides an optomechanical module that matches the exit pupil position of a hybrid scanning optomechanical module based on fiber scanning with the coupling region of the waveguide. Utility Model Content
[0005] The purpose of this application is to provide an optomechanical module, including a scanning unit, a waveguide, and a focalless optical element. The scanning unit includes a fiber scanner, a lens, and a galvanometer. The scanning fiber of the fiber scanner vibrates along a first vibration direction under the drive of a driving signal and forms a linear scanning trajectory. After passing through the lens, the light enters the reflecting surface of the galvanometer. The galvanometer vibrates along a second vibration direction, forming an image under the action of the galvanometer. The beam of the image enters the coupling region of the waveguide under the action of the focalless optical element. The entrance pupil and exit pupil of the focalless optical element are located at opposite ends of the focalless optical element. The distance between the entrance pupil of the focalless optical element and the center of the reflecting surface of the galvanometer is within 2 mm, and the distance between the exit pupil of the focalless optical element and the coupling region of the waveguide is within 2 mm.
[0006] Preferably, in some embodiments, the afocal optical element includes an objective lens group and an eyepiece lens group. The distance between the entrance pupil position of the objective lens group and the center position of the reflecting surface of the galvanometer is within 2 mm, and the distance between the exit pupil position of the eyepiece lens group and the coupling region of the waveguide is within 2 mm. The objective lens group receives the image light reflected by the galvanometer, and the eyepiece lens group receives the image light from the objective lens group and projects the image light onto the coupling region of the waveguide.
[0007] Preferably, in some embodiments, the relationship between the entrance pupil distance of the objective lens group and the focal length of the objective lens group and the focal length of the eyepiece lens group is as follows:
[0008]
[0009] Where f1 is the focal length of the objective lens group, f2 is the focal length of the eyepiece lens group, and l is the entrance pupil distance of the objective lens group.
[0010] Preferably, in some embodiments, an optical path deflector is provided between the objective lens group and the eyepiece lens group, the optical path deflector being located on the light output path of the objective lens group and the eyepiece lens group being located on the light reflection path of the optical path deflector.
[0011] Preferably, in some embodiments, the ratio of the change in exit pupil distance to the change in entrance pupil distance of the afocal optical element is less than 1.5, the change in entrance pupil distance is the distance between the exit pupil position of the lens and the entrance pupil position of the afocal optical element, and the change in entrance pupil distance is less than 0.5 mm.
[0012] Preferably, in some embodiments, the afocal optical element includes an equivalent negative refractive index or negative refractive index planar lens, which causes light to converge again to form an image.
[0013] Preferably, in some embodiments, the first display direction and the second display direction are spatially perpendicular, corresponding to the horizontal and vertical axes of the displayed image.
[0014] This specification also provides a near-eye display device, including an eyeglass body and the aforementioned optomechanical module, wherein the eyeglass body includes a frame and temples, the waveguide is located in the frame, and the fiber optic scanner, the lens, and the galvanometer are disposed on the temples or the frame.
[0015] The technical solution adopted in this application embodiment can achieve the following technical effects: by setting a focal-free optical element between the galvanometer and the waveguide, the exit pupil position of the optomechanical module can be adjusted so that the light convergence point of the limiting scanning unit in the first display direction is close to the coupling region of the waveguide and the light convergence point in the second display direction is located at the galvanometer. This makes the light spot at the exit pupil position of the optomechanical module match the coupling region of the waveguide, thereby ensuring that the beam size of the entire field of view is minimized when the light spot enters the coupling region, and improving the imaging quality of the optomechanical module.
[0016] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the technical solutions of this application. The objectives and other advantages of this application may be realized and obtained by means of the structures and / or processes particularly pointed out in the description, claims and drawings. Attached Figure Description
[0017] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:
[0018] Figure 1 This is a schematic diagram of the optical-mechanical module provided in the embodiments of this application;
[0019] Figure 2 This is a schematic diagram of the structure of the near-eye display device provided in the embodiments of this application;
[0020] Figure 3A This is a schematic diagram of the structure of an optomechanical module provided in an embodiment of this application;
[0021] Figure 3B This is a schematic diagram of the structure of an optomechanical module provided in an embodiment of this application;
[0022] Figure 4 This is a schematic diagram of the waveguide structure provided in an embodiment of this application;
[0023] Figure 5 This is a schematic diagram of a focal-free optical element applied to an optomechanical module according to an embodiment of this application;
[0024] Figure 6 This is a schematic diagram of another afocalless optical element provided in this application embodiment applied to an optomechanical module;
[0025] Figure 7 This is a schematic diagram of another afocalless optical element provided in the embodiments of this application. Detailed Implementation
[0026] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.
[0027] Figure 1 This is a schematic diagram of the optical-mechanical module provided in an embodiment of this application. Please refer to it. Figure 1 The optomechanical module 100 may include a scanning unit and a waveguide 14. The scanning unit includes a fiber optic scanner 11, a lens 12, and a galvanometer 13. The fiber optic scanner 13 mainly includes a fiber optic actuator 111 and a scanning fiber 112.
[0028] The fiber optic actuator 111 can be a piezoelectric actuator and can be placed inside a base. Typically, the scanning fiber 112 can be cantilevered and mounted on the surface of the fiber optic actuator 111. That is, the emitting end of the scanning fiber 112 is suspended outside the fiber optic actuator 111, while the input end can be coupled to the laser emitter to receive the laser beam. The driving circuit of the fiber optic actuator 111 provides the driving signal, enabling the fiber optic actuator 111 to vibrate at a set operating frequency, further driving the scanning fiber 112 in a plane (e.g., ...). Figure 1Vibration scanning within the XZ plane (as shown).
[0029] The scanning fiber 112, serving as a flexible transmission and mode-controlled laser transmission medium, typically employs a cantilever structure. One end of the scanning fiber 112 is fixed to the fiber actuator 111, while the other end serves as the light-emitting end for scanning. Its scanning mode can be achieved by controlling the vibration frequency and phase of the fiber actuator 111.
[0030] The laser beam projected by the scanning fiber 112 can always be monochromatic, achieving a monochromatic projected image. Alternatively, it can use time-division multiplexing to change the intensity and color of the laser beam projected by the scanning fiber at different times, based on the image information to be displayed, so that the laser beam projected by the scanning fiber 112 matches the laser color and intensity at a specific projection point at a certain moment. Another method for color projection is to use an RGB single-mode fiber, directly projecting the mixed beam at the RGB light source input for each pixel. However, after the beam exits at the output end of the scanning fiber 112, interference and divergence are inevitable, affecting image quality.
[0031] When the light beam is emitted from the output end of the scanning fiber 112, it is inevitably subject to interference. Therefore, in order to improve the imaging quality, an optical component, such as a lens 12, can be set in the optical path so that the light beam emitted from the output end of the scanning fiber 112 can be adjusted. At the same time, it is necessary to minimize the volume and size of the entire laser scanning device as much as possible without affecting the imaging quality, so as to meet the miniaturization requirements of the application products.
[0032] The galvanometer 13, as a key actuator for beam deflection, achieves two-dimensional spatial deflection of the laser beam by changing the angle of the reflecting mirror surface. It is classified into two types: single-axis (line scanning) and dual-axis (area scanning). When the beam emitted from the light-emitting surface of the lens 12 is reflected by the galvanometer, the optical path can be adjusted to form an image on the desired imaging surface. Specifically, based on the working principle of the galvanometer, it can be classified as a piezoelectric galvanometer, electromagnetic galvanometer, etc. The galvanometer includes a reflecting mirror; under external drive, the reflecting mirror can rotate around an axis, which is related to... Figure 1 The X-direction shown is parallel and vibrates back and forth at a set frequency. The mirror can be connected to the rotating shaft in different ways, for example, it can be placed in a frame with a rotating shaft and rotatably fitted onto a rotating shaft. The galvanometer and the fiber optic actuator 111 can share a unified external circuit, which provides different driving signals so that the two have different operating frequencies.
[0033] Continue to refer to Figure 1 The scanning fiber 112 of the fiber optic scanner 11 is driven by a driving signal along a first vibration direction (e.g., Figure 1The X-axis (as shown) vibrates and forms a linear scanning trajectory, which, after passing through lens 12, enters the reflecting surface of galvanometer 13. Galvanometer 13 vibrates along the second vibration direction (e.g., Figure 1 The vibration (shown on the Y-axis) forms an image under the action of the galvanometer 13 and enters the coupling region 141 of the waveguide 14.
[0034] It should be noted that in the embodiments of this specification, the first vibration direction and the second vibration direction are not consistent with the display direction of a conventional scanning display system. (Refer to...) Figure 1 Ideally, a three-dimensional XYZ coordinate system is established with any point of the fiber optic scanner or lens in the optomechanical module as the origin. One side of the galvanometer is parallel to the X-axis, so its vibration direction is consistent with the Y-axis. The scanning unit only needs to vibrate parallel to the X-axis. In this case, the direction perpendicular to the paper can be regarded as the first vibration direction (e.g., ...). Figure 1 The X-axis shown in the figure, the height direction of the fiber optic scanner and lens can be regarded as the second vibration direction (e.g., the X-axis). Figure 1 The Y-axis is shown in the diagram, and the optical axis of the fiber optic scanner and lens is the Z-axis. To more clearly illustrate the relationship between the first vibration direction, the second vibration direction, the first display direction, and the second display direction, a three-dimensional xyz coordinate system is established with any point on the waveguide as the origin. Specifically, the length direction of the waveguide (perpendicular to the paper) is the x-axis, the height direction of the waveguide is the y-axis, and the thickness direction of the waveguide is the z-axis. (Continue referring to...) Figure 1 Here, the first display direction is the same as the first vibration direction, and the second display direction is the same as the second vibration direction. However, in the design of near-eye display devices, to ensure wearing comfort, the lenses and temples are usually vertically aligned. The specific structure of the eyeglass frame is referenced... Figure 2 Furthermore, to ensure that the light output direction of the near-eye display device can be controlled in the central field of view, the fiber optic scanner of the optomechanical module rotates according to the reflected light path of the lens. Since there may be a deflection in the light path between the scanning unit and the galvanometer, the optical axis will rotate. When the vibration direction (e.g., the first vibration direction) rotates along one axis of the spatial coordinate system XYZ, it will cause the display direction (e.g., the first display direction) to rotate along the other axis. This results in the first vibration direction and the first display direction not being parallel in space. In practical applications, the rotation is performed in space according to the reflected light path of the lens, and the specific rotation angle is determined based on the angle between the temple and the lens. Further, the first display direction and the second display direction remain perpendicular in space, corresponding to the horizontal and vertical axes of the displayed image, respectively.
[0035] In waveguide design, a larger coupling region size leads to increased secondary diffraction of the beam entering the coupling region. Therefore, the incident light spots on the waveguide coupling region need to overlap as much as possible, and the coupling region size needs to be sufficiently small while ensuring assembly tolerances. Furthermore, the tolerances of lenses in the optical module and the influence of system assembly precision make it difficult for the exit pupil position of the lens to coincide with the center region of the galvanometer in practical applications. To address these issues, this specification provides an optomechanical module with a focalless optical element. The focalless optical element can adjust the exit pupil position of the optomechanical module so that the exit pupil position is located near the coupling region of the waveguide.
[0036] Figure 3A and Figure 3B This is a schematic diagram of the structure of an optomechanical module provided in an embodiment of this application. For example... Figure 3A and Figure 3B As shown, the optomechanical module includes a scanning unit, a focal-afocal optical element 16, and a waveguide 14. The scanning unit includes a fiber optic scanner, a lens, and a galvanometer 13. Figure 3A and 3B The shaded area represents the fiber optic scanner and lens, which are arranged coaxially. The galvanometer 13 is located on the light exit path of the lens and near the exit pupil of the lens. The scanning fiber of the fiber optic scanner is along the first vibration direction. Figure 3A and Figure 3B The vibration (in the X-axis direction shown) forms a linear scanning trajectory, which is emitted through the lens and projected onto the reflecting surface of the galvanometer. The galvanometer moves along the second vibration direction (…). Figure 3A and Figure 3B Vibration along the Y-axis (as shown) forms a two-dimensional image through a linear scanning trajectory under the action of a galvanometer. Further, a focalless optical element 16 is located on the light exit path of the galvanometer's reflective surface. This focalless optical element 16 controls the light path's deflection and adjusts the exit pupil position of the optical module, ensuring the exit pupil position is near the coupling region 141 of the waveguide 14. The entrance pupil and exit pupil positions of the focalless optical element 16 are located at its two ends, with the entrance pupil position near the center of the galvanometer 13's reflective surface and the exit pupil position near the coupling region 141 of the waveguide 14. It should be noted that "nearby" here can be understood as within a specific range (e.g., no greater than 2mm or no greater than 1mm). For example, the distance between the exit pupil of the optical module and the coupling region of the waveguide is no greater than 2mm; the distance between the entrance pupil of the afocal optical element and the center of the galvanometer reflector is no greater than 2mm; and the distance between the exit pupil of the afocal optical element and the coupling region of the waveguide is no greater than 2mm. Furthermore, such as... Figure 4As shown, this application adjusts the exit pupil position of the optomechanical module by setting a focalless optical element between the waveguide and the galvanometer. The shape of the coupling region 141 of the waveguide 14 can be circular, so that the size of the coupling region can be designed to be small, while ensuring that the beam size of the entire field of view is minimized when the light spot enters the coupling region, thereby improving the imaging quality of the optomechanical module.
[0037] To provide a clearer description of afocal optical elements, the present application provides the following embodiments for illustration.
[0038] Figure 5 This is a schematic diagram of a focal-free optical element applied to an optomechanical module according to an embodiment of this application specification. Figure 5 As shown, the optical axes of the fiber optic scanner and lens are approximately parallel to the waveguide, and the reflecting surface of the galvanometer is located on the light-emitting path of the lens. Further, the afocal optical element 16 may include an objective lens group and an eyepiece lens group, which are arranged along the same optical axis. The objective lens group and eyepiece lens group are located on the light-emitting path of the galvanometer's reflecting surface. The incident surface of the objective lens group is opposite to the reflecting surface of the galvanometer, and the emitting surface of the eyepiece lens group is opposite to the coupling region 141 of the waveguide 14. The image light reflected by the galvanometer 13 passes sequentially through the objective lens group and the eyepiece lens group into the coupling region of the waveguide. It should be noted that the approximately parallel arrangement of the optical axes of the fiber optic scanner and lens to the waveguide can be understood as meaning that the optical axes of the fiber optic scanner and lens can be parallel to the waveguide, or they can have a certain angle between them. For example, the angle between the optical axes of the fiber optic scanner and lens and the surface of the waveguide is no greater than 15 degrees.
[0039] It should be noted that, Figure 5 The arrangement of the fiber optic scanner and lens relative to the waveguide shown is merely an example. When applied to near-eye display devices, the fiber optic scanner and lens can be placed within the frame, but their placement relative to the waveguide is not limited to the above. Figure 5In other alternative embodiments, the placement of the fiber optic scanner and lens relative to the waveguide can be adjusted according to the actual application. For example, when considering mounting the fiber optic scanner and lens on the temple, they are approximately perpendicular to the waveguide, and the structural composition of the afocal optical element will be changed accordingly. Specifically, in some embodiments, the afocal optical element may include an objective lens group, an eyepiece lens group, and an optical path deflector. The optical path deflector is used to control the reversal of the optical path. Specifically, the optical path deflector is located between the objective lens group and the eyepiece lens group. The image light reflected by the galvanometer passes through the objective lens group and is projected onto the reflecting surface of the mirror for reflection. The reflected image light then enters the eyepiece lens group. In some embodiments, the optical path deflector can be a plane mirror or a prism. This specification uses a plane mirror as an example for the optical path deflector; see reference for details. Figure 6 And its related descriptions.
[0040] Figure 6 This is a schematic diagram of another afocalless optical element applied to an optomechanical module according to an embodiment of this application. (Refer to...) Figure 6 The afocal optical element 16 may include an objective lens group 161, an eyepiece lens group 162, and a reflecting mirror 163, with the reflecting mirror 163 located between the objective lens group 161 and the eyepiece lens group 162. Figure 3A , Figure 3B and Figure 6 The incident surface of the objective lens group 161 is on the exit light path of the galvanometer reflecting surface. The image light reflected by the galvanometer passes through the objective lens group 161 and is projected onto the reflecting surface of the mirror 163 for reflection. The reflected image light enters the eyepiece lens group 162. The coupling region 141 of the waveguide 14 is located on the exit light path of the exit surface of the eyepiece lens group 162. The image light exiting from the exit surface of the eyepiece lens group 163 is incident on the coupling region 141 of the waveguide 14. It should be noted that... Figure 6 The example shown, where both the eyepiece and objective lens groups have only one lens, is for illustrative purposes only. In actual applications, both groups can have multiple lenses, which can be adjusted according to specific application scenarios and needs. Furthermore, the number of lenses in the eyepiece and objective lens groups can be the same or different.
[0041] Considering the influence of lens tolerances and system assembly precision, the focal length distribution of the objective lens group and eyepiece lens group and the entrance pupil position in afocal optical element need to meet certain conditions, which will be explained in detail below.
[0042] Assuming the focal length of the objective lens group in an afocal optical element is f1, the focal length of the eyepiece lens group is f2, and the entrance pupil distance of the objective lens group is l, then the exit pupil distance of the eyepiece lens group is l′. Therefore, the exit pupil distance of the eyepiece lens group is:
[0043]
[0044] Taking the derivative with respect to l, we get:
[0045]
[0046] To ensure that the difference between the first and second display directions of the entire optomechanical module system is small, generally From this, the relationship between l and focal length can be deduced:
[0047] To ensure a small overall size for the optomechanical module, f1 and f2 are generally greater than 0, from which we can deduce:
[0048] when hour,
[0049]
[0050] when hour,
[0051] or
[0052]
[0053] Since l is less than 0 and cannot be too close to the lens, the relationship between l and the focal lengths f1 and f2 is:
[0054]
[0055] The entrance pupil position of an afocal optical element is related to the exit pupil position of its preceding optical elements (e.g., lenses and galvanometers). During the assembly of the optomechanical module, tolerances can cause misalignment between the entrance pupil position of the afocal optical element and its preceding optical elements. In this embodiment, this misalignment is defined as the change in entrance pupil distance. Similarly, the exit pupil distance of the afocal optical element also changes. To ensure compatibility between the afocal optical element and the lens, the ratio of the change in exit pupil distance to the change in entrance pupil distance is less than 1.5. The change in entrance pupil distance is the distance between the exit pupil position of the lens and the entrance pupil position of the afocal optical element, and this change is less than 0.5 mm.
[0056] Figure 7 This is a schematic diagram of another afocal optical element provided according to an embodiment of this application. (Refer to...) Figure 7 Afocal optical elements are equivalent to or have a negative refractive index, such as flat plate lenses. Please refer to... Figure 3A , Figure 3B as well as Figure 7The negative refractive index flat plate lens is located on the light output path of the reflector surface of the galvanometer 13. One side of the negative refractive index flat plate lens receives the image light emitted from the reflector surface of the galvanometer, and the negative refractive index flat plate lens causes the image light to converge and form an image on the other side. By adjusting the tilt angle of the negative refractive index flat plate lens, the exit pupil position of the lens can be adjusted, thereby making the exit pupil position of the optomechanical module located near the coupling region 141 of the waveguide 14.
[0057] In another possible implementation, this application also provides a near-eye display device, referring to... Figure 2 The near-eye display device includes a glasses body and the aforementioned optomechanical module. The glasses body includes a frame and temples, with a waveguide located in the frame and a fiber optic scanner, lens, and galvanometer mounted on the temples or frame.
[0058] The above description is merely a preferred embodiment of this application. Each embodiment is only used to illustrate the technical solution of this application and is not intended to limit this application. Any technical solution that can be obtained by those skilled in the art through logical analysis, reasoning or effective experimentation based on the concept of this application should be within the scope of this application.
[0059] The various embodiments in this application are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.
[0060] The terms "first," "second," "first," or "second" as used in the various embodiments of this disclosure may modify various components regardless of their order and / or importance, but these terms do not limit the corresponding components. The above terms are configured only for the purpose of distinguishing one component from another.
Claims
1. An optomechanical module, characterized in that, It includes a scanning unit, a waveguide, and a focal-free optical element, wherein the scanning unit includes a fiber optic scanner, a lens, and a galvanometer. The scanning fiber of the fiber scanner vibrates along the first vibration direction under the drive signal and forms a linear scanning trajectory. After passing through the lens, it enters the reflecting surface of the galvanometer. The galvanometer vibrates along the second vibration direction and forms an image under the action of the galvanometer. The beam of the image enters the coupling region of the waveguide under the action of the afocal optical element. The entrance pupil and exit pupil of the afocal optical element are located at opposite ends of the afocal optical element. The distance between the entrance pupil of the afocal optical element and the center of the reflecting surface of the galvanometer is within 2 mm, and the distance between the exit pupil of the afocal optical element and the coupling region of the waveguide is within 2 mm.
2. The optomechanical module according to claim 1, characterized in that, The afocal optical element includes an objective lens group and an eyepiece lens group. The distance between the entrance pupil position of the objective lens group and the center position of the reflecting surface of the galvanometer is within 2 mm. The distance between the exit pupil position of the eyepiece lens group and the coupling region of the waveguide is within 2 mm. The objective lens group receives the image light reflected by the galvanometer, and the eyepiece lens group receives the image light from the objective lens group and projects the image light onto the coupling region of the waveguide.
3. The optomechanical module according to claim 2, characterized in that, The relationship between the entrance pupil distance of the objective lens group and the focal length of the objective lens group and the focal length of the eyepiece lens group is as follows: Where f1 is the focal length of the objective lens group. ， f2 is the focal length of the eyepiece assembly. ， l is the entrance pupil distance of the objective lens group.
4. The optomechanical module according to claim 2 or 3, characterized in that, An optical path deflector is provided between the objective lens group and the eyepiece lens group. The optical path deflector is located on the light output path of the objective lens group, and the eyepiece lens group is located on the light reflection path of the optical path deflector.
5. The optomechanical module according to claim 1, characterized in that, The ratio of the change in exit pupil distance to the change in entrance pupil distance of the afocal optical element is less than 1.
5. The change in entrance pupil distance is the distance between the exit pupil position of the lens and the entrance pupil position of the afocal optical element, and the change in entrance pupil distance is less than 0.5 mm.
6. The optomechanical module according to claim 1, characterized in that, The afocal optical element includes an equivalent negative refractive index or negative refractive index flat plate lens, which allows light to converge again to form an image.
7. The optomechanical module according to claim 1, characterized in that, The first display direction and the second display direction are spatially perpendicular, corresponding to the horizontal and vertical axes of the displayed image.
8. A near-eye display device, characterized in that, The glasses include a main body and an optomechanical module as described in claims 1-7, wherein the main body includes a frame and temples, the waveguide is located in the frame, and the fiber optic scanner, the lens, and the galvanometer are disposed on the temples or the frame.