One-to-two binocular hetero-display AR glasses and image display method

Abstract

The application relates to the technical field of augmented reality display, in particular to a one-to-two binocular different display AR (Augmented Reality) glasses and an image display method, which comprises a light machine module; a light splitting module is arranged in the light emission direction of the light machine module and is used for splitting linearly polarized light image information light beams into first light beams and second light beams, the propagation direction of the first light beams is defined as a first light path, and the propagation direction of the second light beams is defined as a second light path; a first polarization state conversion element is arranged in the first light path; a second polarization state conversion element is arranged in the second light path, and the first polarization state conversion element and the second polarization state conversion element are respectively used for converting the first light beams and the second light beams into light beams with a first specific circular polarization state; a first waveguide lens is coupled with the end of the first light path; and a second waveguide lens is coupled with the end of the second light path. The application has the effect of improving the use experience of users.

Description

Technical Field

[0001] This application relates to the field of augmented reality display technology, and in particular to a dual-lens AR glasses with one-to-two display and an image display method. Background Technology

[0002] Currently, augmented reality (AR) technology is developing rapidly, demonstrating enormous application potential in multiple fields. AR glasses, as a crucial hardware platform for this technology, can provide users with information prompts such as outdoor cycling navigation, real-time translation, AI object recognition, and conference presentations, greatly enriching people's lives and work experiences. With technological advancements, people are placing higher demands on the performance, appearance, and user experience of AR glasses.

[0003] In related technologies, AR glasses often employ various technical solutions to achieve image display functionality. A common approach is based on the traditional surface-embossed grating waveguide design (SRG waveguide design). For example, the Even Realities G1 smart glasses use a one-to-one binocular simultaneous display structure for a 25° field of view (FOV) head-up display. This one-to-one binocular simultaneous display structure refers to using one optical engine module corresponding to one waveguide lens, with each eye equipped with an independent optical engine and waveguide lens system. Both systems simultaneously display the same image information.

[0004] Regarding the aforementioned technologies: the periodic microstructures in the SRG grating region strongly scatter ambient light, resulting in a significant visual presence of the grating region and compromising the overall integrity and concealment of the lens appearance; at the same time, zero-order diffraction leakage causes light to escape in non-target directions, which not only poses a privacy risk of leaking displayed content, but also creates stray light background inside the waveguide, thereby degrading the user experience. Summary of the Invention

[0005] To improve the user experience, this application provides a dual-lens AR glasses with one-to-two different display and an image display method.

[0006] Firstly, this application provides a dual-lens AR glasses system with one-to-two different display capabilities, which adopts the following technical solution:

[0007] A type of dual-lens AR glasses with different display modes, comprising:

[0008] Optomechanical module, used to output linearly polarized light image information beam;

[0009] A beam splitting module is disposed in the light output direction of the optomechanical module to split the linearly polarized light image information beam into a first beam and a second beam, defining the propagation direction of the first beam as the first optical path and the propagation direction of the second beam as the second optical path.

[0010] A first polarization state conversion element is disposed in the first optical path;

[0011] A second polarization state conversion element is disposed in the second optical path. The first polarization state conversion element and the second polarization state conversion element are respectively used to convert the first beam and the second beam into beams with a first specific circular polarization state.

[0012] The first waveguide lens is coupled to the end of the first optical path;

[0013] The second waveguide lens is coupled to the end of the second optical path;

[0014] Both the first waveguide lens and the second waveguide lens are polarization-selective waveguides. They have a first diffraction efficiency for a beam of light in the first specific circular polarization state and a second diffraction efficiency for a beam of light in the second specific circular polarization state with the opposite rotation direction to the first specific circular polarization state. The first diffraction efficiency is higher than the second diffraction efficiency.

[0015] By adopting the above technical solution, the optomechanical module outputs linearly polarized light image information, and the beam splitting module splits it into a first beam and a second beam. The first polarization state conversion element and the second polarization state conversion element convert the beam into a first specific circular polarization state, and then couple it into the first waveguide lens and the second waveguide lens respectively. By utilizing the different diffraction efficiencies of polarization-selective waveguides for beams of different polarization states, a one-to-two binocular display can be realized. This can better control the light propagation, improve the light efficiency, and reduce costs. In addition, polarization-selective waveguides can also make the grating area highly visually concealed, without light leakage or rainbow patterns, thus improving the appearance of AR glasses and the user experience.

[0016] Optionally, the optical engine module is a liquid crystal silicon-coated optical engine, and the display chip area of ​​the liquid crystal silicon-coated optical engine is divided into a first display area and a second display area, which are used to generate different image information for the left eye and the right eye to view, respectively.

[0017] By adopting the above technical solution, the display chip area of ​​the liquid crystal silicon-coated optomechanism is divided into a first display area and a second display area for generating different image information for the left and right eyes, respectively, thus realizing the function of one-to-two binocular display. Compared with the traditional one-to-one binocular simultaneous display structure, this significantly reduces the cost of the optomechanism while meeting people's daily needs for different binocular displays.

[0018] Optionally, the first waveguide lens and the second waveguide lens are spaced apart and arranged in a figure-eight shape. The angle between the first waveguide lens and the second waveguide lens and the horizontal plane is 1-5°, and the angle between the first waveguide lens and the second waveguide lens and the vertical plane is 4-8°.

[0019] By adopting the above technical solution, the first and second waveguide lenses are spaced apart and arranged in a figure-eight shape, with angles of 1-5° to the horizontal plane and 4-8° to the vertical plane. This layout better adapts to the visual range and viewing angle characteristics of the human eye. Compared with conventional parallel or other layouts, this allows image information coupled from the waveguide lenses to enter the human eye more accurately, reducing light loss and deviation during propagation, thereby improving the clarity and comfort of the image received by the human eye. Simultaneously, this angle setting optimizes the light propagation path within the lens, fully utilizing the effective area of ​​the lens for beam diffraction and transmission, further enhancing the overall optical efficiency and display effect of the glasses.

[0020] Optionally, both the first polarization state conversion element and the second polarization state conversion element are quarter-wave plates.

[0021] By adopting the above technical solution, the linearly polarized light image information output by the optomechanical module is divided into a first beam and a second beam by the beam splitter. The first beam and the second beam pass through a quarter-wave plate, which serves as the first polarization state conversion element and the second polarization state conversion element, respectively. This converts the linearly polarized light into a beam with a first specific circular polarization state, so that the first waveguide lens and the second waveguide lens, two polarization-selective waveguides, can efficiently diffract and transmit the beam with the first specific circular polarization state, thereby realizing a one-to-two binocular differential display image.

[0022] Optionally, the first specific circular polarization state is a right-handed circular polarization state.

[0023] By adopting the above technical solution, using the first specific circular polarization state of right-hand circular polarization, combined with the high diffraction efficiency of a single-order polarization selective waveguide, it is possible to better control light propagation and achieve better uniformity.

[0024] Optionally, the polarization-selective waveguide is a polarization volume holographic grating waveguide, which is made of liquid crystal polymer material.

[0025] By adopting the above technical solution, using a polarizing holographic grating waveguide made of liquid crystal polymer material, the characteristics of volume Bragg diffraction and single-order high diffraction efficiency can be utilized to better control light propagation, achieving better uniformity than multi-order diffraction SRGs. At the same time, the grating area has high visual concealment, no light leakage, and no rainbow patterns, greatly improving the appearance of AR glasses and the user experience. Furthermore, by adapting this polarizing holographic grating waveguide to an optomechanical module that outputs a specific circular polarization state, the advantages of polarized light response characteristics can be greatly utilized, which can significantly improve the diffraction efficiency of the optical waveguide.

[0026] Optionally, the polarizing holographic grating waveguide includes an input grating, a bend grating, and an output grating, with the bend grating located below the output grating. The input grating, the bend grating, and the output grating are used to guide the propagation of the light beam in sequence.

[0027] By adopting the above technical solution, the polarizing holographic grating waveguide is equipped with an input grating, a deflection grating, and an output grating, with the deflection grating located below the output grating, guiding the beam propagation sequentially. This structure allows the beam to be transmitted in an orderly manner along a preset path. First, the input grating couples the beam into the waveguide, then the deflection grating changes the beam's propagation direction, and finally, the output grating couples the beam out to the human eye. Compared to traditional optical waveguide structures, this structure better utilizes the characteristics of the polarizing holographic grating waveguide, combined with its high diffraction efficiency only for specific polarized light states, ensuring high diffraction efficiency during beam propagation, reducing light loss, and thus improving the overall optical efficiency of the AR glasses. This results in a clearer and brighter display, enhancing the user experience. Simultaneously, this orderly beam guidance method also helps reduce stray light generation, minimizing interference with the displayed image and improving image contrast and quality.

[0028] Optionally, the first diffraction efficiency is higher than 90%, and the second diffraction efficiency is lower than 1%.

[0029] By adopting the above technical solution, the polarization-selective waveguide has a high diffraction efficiency of over 90% for a beam of light in the first specific circular polarization state and a low diffraction efficiency of less than 1% for a beam of light in the second specific circular polarization state with opposite rotation direction. This allows for better control of light propagation, achieving better uniformity, and avoiding stray light generated by diffraction, which can reduce contrast and create ghosting. It can also reduce the visual presence of the grating area, light leakage, rainbow patterns, and other phenomena, improving the appearance of AR glasses and the user experience. At the same time, it also helps to improve the system optical efficiency of AR glasses.

[0030] Optionally, the system optical efficiency of AR glasses is defined as the ratio of the light flux emitted from the first waveguide lens and the second waveguide lens and received by the human eye to the light flux emitted from the optomechanical module, and is higher than 5000 nit / lm.

[0031] By adopting the above technical solution, the ratio of the light flux received by the human eye from the waveguide lens to the light flux emitted from the optomechanical module is higher than 5000 nit / lm, which improves the light efficiency of AR glasses.

[0032] Secondly, the image display method for dual-lens AR glasses provided in this application adopts the following technical solution:

[0033] A method for displaying images in a dual-lens AR glasses system includes the following steps:

[0034] Generation: A linearly polarized light image information beam is generated by an optomechanical module;

[0035] Beam splitting: The linearly polarized light image information beam is split into a first beam and a second beam;

[0036] Conversion: Converting the polarization states of the first beam and the second beam from linear polarization to a first specific circular polarization state;

[0037] Coupling and diffraction: The first beam and the second beam, after polarization state conversion, are coupled into the first waveguide lens and the second waveguide lens, respectively. The first waveguide lens and the second waveguide lens diffract and transmit the beam of the first specific circular polarization state and finally couple it out to the human eye.

[0038] In summary, this application includes at least one of the following beneficial technical effects:

[0039] 1. After the linearly polarized light output from the optomechanical module is split and polarization state converted, it is transmitted by a polarization-selective waveguide with high diffraction efficiency for the first specific circularly polarized beam. This greatly improves the diffraction efficiency of the waveguide, making the optical efficiency of the AR glasses system higher than 5000 nit / lm, thus improving the light efficiency utilization. In addition, the polarization-selective waveguide also makes the grating area highly visually concealed, with no light leakage and no rainbow pattern, improving the appearance of the AR glasses and the user experience.

[0040] 2. It adopts a one-to-two dual-lens display structure, which greatly reduces the cost of optical engines and power consumption compared with the dual-optical-engine structure while ensuring that the display brightness can meet the needs of daily use. Attached Figure Description

[0041] Figure 1 This is a top view of a dual-lens AR glasses with one-to-two display according to an embodiment of this application.

[0042] Figure 2 This is a side view of a dual-lens AR glasses with one-to-two display according to an embodiment of this application.

[0043] Figure 3 This is a schematic diagram of the structure of the polarizing holographic grating waveguide in the embodiment of this application.

[0044] Figure 4 This is a spectral diagram of the optomechanical module in the embodiments of this application.

[0045] Figure 5 This is the spectral response bandwidth diagram of the coupled grating in the embodiments of this application.

[0046] Explanation of reference numerals in the attached figures:

[0047] 1. Optomechanical module; 2. Beam splitting module; 3. First polarization state conversion element; 4. Second polarization state conversion element; 5. First waveguide mirror; 6. Second waveguide mirror; 7. Coupled-in grating; 8. Turning grating; 9. Coupled-out grating. Detailed Implementation

[0048] The following is in conjunction with the appendix Figure 1-5 This application will be described in further detail.

[0049] This application discloses a dual-lens AR glasses with one-to-two display.

[0050] It should be noted that, in the description of this invention, the terms "center," "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 invention 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, they should not be construed as limitations on this invention.

[0051] Reference Figure 1 The dual-lens AR glasses include an optical engine module 1, a beam splitter module 2, a first polarization state conversion element 3, a second polarization state conversion element 4, a first waveguide lens 5, and a second waveguide lens 6. The beam splitter module 2 is positioned in the light-emitting direction of the optical engine module 1. The first polarization state conversion element 3 is located in the first optical path, and the second polarization state conversion element 4 is located in the second optical path. The first waveguide lens 5 is coupled to the end of the first optical path, and the second waveguide lens 6 is coupled to the end of the second optical path.

[0052] Specifically, the optical engine module 1 is used to output a linearly polarized light image information beam. In this embodiment, the optical engine module 1 is a liquid crystal on silicon (LCOS) optical engine, which features small size and low power consumption. Furthermore, the display chip area of ​​the LCOS optical engine is divided into a first display area and a second display area, used to generate different image information for the left and right eyes, respectively. The display chip can be a high-resolution LCOS chip to ensure clear image display.

[0053] In other embodiments, in some special application scenarios, other similar display chips can be used to replace the LCOS chip, as long as they can meet the requirements for outputting linearly polarized light image information.

[0054] It should be noted that, in order to achieve the ideal display effect and meet the requirements of head-up display, the horizontal incident angle of the LCOS optical engine is 3° and the vertical incident angle is 16°. Furthermore, the eyebox is designed to be 12mm x 10mm in size.

[0055] The beam splitter 2 is used to split the linearly polarized light image information beam into a first beam and a second beam, defining the propagation direction of the first beam as the first optical path and the propagation direction of the second beam as the second optical path.

[0056] The beam splitter module 2 can employ a BS beam splitter, which can split the incident light into two beams at a certain ratio. The BS beam splitter has advantages such as high splitting efficiency and stable splitting ratio. In other embodiments, other types of beam splitting devices, such as polarizing beam splitters, can also be used, as long as they can achieve the function of splitting linearly polarized light into two beams.

[0057] The first polarization state conversion element 3 is disposed on the first waveguide lens 5, and the second polarization state conversion element 4 is disposed on the second waveguide lens 6. The first polarization state conversion element 3 and the second polarization state conversion element 4 are respectively used to convert the first beam and the second beam into beams of a first specific circular polarization state, and couple the beams of the first specific circular polarization state into the first waveguide lens 5 and the second waveguide lens 6.

[0058] The first specific circular polarization state is a right-handed circular polarization state. Both the first polarization state conversion element 3 and the second polarization state conversion element 4 are quarter-wave plates, so as to facilitate the conversion of linearly polarized light into circularly polarized light using quarter-wave plates.

[0059] In this embodiment, the quarter-wave plate is typically made of a material with birefringence properties, such as a quartz crystal. In other embodiments, other optical elements capable of polarization state conversion can be used instead of the quarter-wave plate, such as certain specially designed polarization conversion films.

[0060] The first waveguide lens 5 and the second waveguide lens 6 are symmetrically arranged along the optomechanical module 1 in a figure-eight pattern, and the first waveguide lens 5 and the second waveguide lens 6 are spaced apart, so that the light beams in the first waveguide lens 5 and the second waveguide lens 6 are not easily interfered with each other, ensuring the independence and clarity of the left and right eye images, improving the effect of binocular display and the user experience.

[0061] Reference Figure 1 and Figure 2 The first waveguide lens 5 and the second waveguide lens 6 both have angles θ1 of 1-5° with the horizontal plane, and angles θ2 of 4-8° with the vertical plane. This arrangement conforms to the visual habits of the human eye and provides a better viewing experience. In this embodiment, the first waveguide lens 5 and the second waveguide lens 6 both have angles θ1 of 3° with the horizontal plane, and angles θ2 of 6° with the vertical plane.

[0062] Both the first waveguide lens 5 and the second waveguide lens 6 are polarization-selective waveguides. Specifically, the polarization-selective waveguide is a polarization volume holographic grating waveguide, which is made of liquid crystal polymer material. Liquid crystal polymer material has good optical properties and processability.

[0063] Both the first waveguide lens 5 and the second waveguide lens 6 have a first diffraction efficiency for a beam of light in a first specific circular polarization state, and a second diffraction efficiency for a beam of light in a second specific circular polarization state with the opposite rotation direction to the first specific circular polarization state. The first diffraction efficiency is higher than the second diffraction efficiency.

[0064] In this embodiment, the first diffraction efficiency is higher than 90%, and the second diffraction efficiency is lower than 1%. This ensures that only light conforming to the first specific circular polarization state can be transmitted efficiently, effectively reducing interference from stray light.

[0065] The system optical efficiency of AR glasses is defined as the ratio of the light flux received by the human eye from the first waveguide lens 5 and the second waveguide lens 6 to the light flux emitted from the optomechanical module 1, and it is higher than 5000 nit / lm, thereby greatly improving the light efficiency utilization.

[0066] Reference Figure 3 The polarizing holographic grating waveguide includes an input grating 7, a deflection grating 8, and an output grating 9. The deflection grating 8 is located below the output grating 9. The input grating 7 is responsible for coupling the light beam into the waveguide lens. The deflection grating 8 can change the propagation direction of the light beam to transmit the light beam to the output grating 9, thereby facilitating the output grating 9 to couple the light beam out to the human eye.

[0067] In this embodiment, the grating uses a liquid crystal material that responds to right-hand circularly polarized light beams, and the material has an average refractive index of 1.7, a minimum modulated refractive index of 1.5, and a refractive index modulation amplitude of 0.2. The waveguide substrate is a glass substrate made of H-K9L material with a refractive index of 1.52 and a thickness of 0.5 mm.

[0068] Furthermore, the structures and parameters of the coupling grating 7, the transition grating 8, and the coupling grating 9 were optimized to achieve high diffraction efficiency and good uniformity. For example, the grating k-space vector, grating layout, grating period, and grating thickness were optimized by using Matlab, Lumerical, and Zemax in conjunction with these technologies. Specific periodic structure parameters are shown in the table below.

[0069] Reference Figure 3 and Figure 4The coupling grating 7 achieves a diffraction efficiency of over 90% for right-handed circularly polarized beams in the 500nm-560nm range, while its diffraction efficiency for left-handed circularly polarized beams is only 0.2%, with a polarization suppression ratio of 27dB. Comparison shows good spectral range compatibility with the LCOS optical engine (see reference). Figure 5 ).

[0070] The implementation principle of this embodiment is as follows: The dual-lens AR glasses of this embodiment output linearly polarized light through the optomechanical module 1. After being split by the beam splitting module 2, the linearly polarized light is converted into right-hand circularly polarized light by the first polarization state conversion element 3 and the second polarization state conversion element 4, and then efficiently transmitted by the polarizing holographic grating waveguide. This structure avoids many problems of traditional SRG optical waveguides, such as low light efficiency, light leakage, and rainbow patterns. At the same time, the dual-lens structure reduces cost and energy consumption, improves the overall performance of the AR glasses, and provides users with a better user experience, representing a significant improvement and enhancement compared to existing technologies.

[0071] This application also discloses an image display method for dual-lens AR glasses with different display modes, including the following steps:

[0072] Generation: A beam of linearly polarized light image information is generated by an optomechanical module 1. The optomechanical module 1 can be the liquid crystal silicon-coated optomechanical system described in the above embodiments, with its display chip area divided into a first display area and a second display area, generating different image information for the left and right eyes respectively. When generating the linearly polarized light image information, it is necessary to ensure that parameters such as image resolution and color reproduction meet the display requirements of AR glasses. High-quality image generation can be achieved by optimizing the driving circuit and control algorithm of the optomechanical module 1.

[0073] Beam splitting: The linearly polarized light image information beam is split into a first beam and a second beam. A beam splitting module 2, such as a BS beam splitter or a polarizing beam splitter prism, can be used to split the linearly polarized light output from the optomechanical module 1 into two beams at a certain ratio, used for display in the left and right eyes respectively. During beam splitting, it is necessary to ensure the stability and accuracy of the splitting process to avoid problems such as uneven light intensity or deviation in the beam splitting ratio.

[0074] Conversion: The polarization state of the first and second beams is converted from linear polarization to a specific circular polarization state. This conversion can be achieved using polarization state conversion elements such as quarter-wave plates or novel polarization conversion films. During the conversion process, it is crucial to ensure the accuracy of the polarization state conversion to guarantee that subsequent waveguide mirrors can efficiently diffract and transmit light with the specific polarization state.

[0075] Coupling and Diffraction: The first and second beams, after polarization state conversion, are coupled into the first waveguide mirror 5 and the second waveguide mirror 6, respectively. The first waveguide mirror 5 and the second waveguide mirror 6 diffract and propagate the beams of the first specific circularly polarized state, and finally couple them out to the human eye. The coupling grating 7, the deflection grating 8, and the coupling grating 9 in the waveguide mirrors work together to guide the propagation path of the beams. During the coupling and diffraction process, it is necessary to ensure efficient beam transmission and accurate coupling out to avoid problems such as light loss and image distortion.

[0076] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A pair of binocular AR glasses with dual-lens display, characterized in that, include: Optical engine module (1) is used to output linearly polarized light image information. The optical engine module (1) is a liquid crystal silicon-coated optical engine. The display chip area of ​​the liquid crystal silicon-coated optical engine is divided into a first display area and a second display area, which are used to generate different image information for the left eye and the right eye to view, respectively. The beam splitting module (2) is set in the light output direction of the optomechanical module (1) and is used to split the linearly polarized light image information beam into a first beam and a second beam. The propagation direction of the first beam is defined as the first optical path and the propagation direction of the second beam is defined as the second optical path. The first polarization state conversion element (3) is disposed in the first optical path; The second polarization state conversion element (4) is disposed in the second optical path. The first polarization state conversion element (3) and the second polarization state conversion element (4) are respectively used to convert the first beam and the second beam into beams of a first specific circular polarization state. The first waveguide lens (5) is coupled to the end of the first optical path; The second waveguide lens (6) is coupled to the end of the second optical path; The first waveguide lens (5) and the second waveguide lens (6) are spaced apart and arranged in a figure-eight shape. The angles between the first waveguide lens (5) and the second waveguide lens (6) and the horizontal plane are 1-5° respectively, and the angles between the first waveguide lens (5) and the second waveguide lens (6) and the vertical plane are 4-8° respectively. Both the first waveguide lens (5) and the second waveguide lens (6) are polarization-selective waveguides. The polarization-selective waveguide is a polarization volume holographic grating waveguide. The polarization volume holographic grating waveguide is made of liquid crystal polymer material. It has a first diffraction efficiency for the beam of the first specific circular polarization state and a second diffraction efficiency for the beam of the second specific circular polarization state with the opposite rotation direction to the first specific circular polarization state. The first diffraction efficiency is higher than 90%, and the second diffraction efficiency is lower than 1%. The polarizer holographic grating waveguide includes an input grating (7), a bend grating (8), and an output grating (9). The bend grating (8) is located below the output grating (9). The input grating (7), the bend grating (8), and the output grating (9) are used to guide the propagation of the light beam in sequence. The waveguide substrate of the polarizing holographic grating waveguide is a glass substrate with a refractive index of 1.52 and a thickness of 0.5 mm. The system optical efficiency of AR glasses is defined as the ratio of the light flux received by the human eye emitted from the first waveguide lens (5) and the second waveguide lens (6) to the light flux emitted from the optomechanical module (1), and is higher than 5000 nit / lm.

2. The binocular AR glasses with dual-lens display according to claim 1, characterized in that: Both the first polarization state conversion element (3) and the second polarization state conversion element (4) are quarter-wave plates.

3. The dual-lens AR glasses according to claim 1, characterized in that: The first specific circular polarization state is a right-handed circular polarization state.

4. An image display method for binocular AR glasses as described in claim 1, characterized in that, Includes the following steps: Generation: Linearly polarized light image information is generated by an optomechanical module (1); Beam splitting: The linearly polarized light image information beam is split into a first beam and a second beam; Conversion: Converting the polarization states of the first beam and the second beam from linear polarization to a first specific circular polarization state; Coupling and diffraction: The first beam and the second beam after polarization state conversion are coupled into the first waveguide lens (5) and the second waveguide lens (6) respectively. The first waveguide lens (5) and the second waveguide lens (6) diffract and transmit the first beam with a specific circular polarization state and finally couple it out to the human eye.

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