Diffraction optical waveguide device and augmented reality display equipment

Abstract

The invention provides a diffractive optical waveguide device and augmented reality display equipment. The device comprises a substrate, and a coupling-in grating, a first turning grating, a second turning grating and a coupling-out grating which are arranged on the substrate, the first turning grating and the second turning grating are arranged in the diffraction direction of the coupling-in grating, and the distance between the first turning grating and the coupling-in grating is smaller than the distance between the second turning grating and the coupling-in grating; the coupling-out grating is arranged in the first turning direction of the first turning grating and in the second turning direction of the second turning grating; the range of a first turning angle between the diffraction direction and the first turning direction is 45-80 degrees, and the range of a second turning angle between the diffraction direction and the second turning direction is 10-45 degrees. According to the technical scheme, the red light supplement of the diffraction optical waveguide is realized, and the chromatic aberration of an observation end image is reduced.

Description

Technical Field

[0001] This application relates to the field of display technology, and more particularly to a diffractive waveguide device and an augmented reality display device. Background Technology

[0002] Diffractive waveguide technology transmits light beams through a waveguide using total internal reflection, thereby superimposing virtual information onto the real world and providing users with an immersive visual experience.

[0003] Existing diffractive waveguide technology mainly uses the same folding grating to control the propagation direction and path of the input light. Furthermore, different transmission angles are used for the transmission and diffraction of red, green, and blue light when they pass through the same folding grating.

[0004] However, the red light element cannot be fully transmitted to the display device in the same grating, resulting in visual abnormalities such as color difference in the final displayed image. Summary of the Invention

[0005] This application provides a diffractive waveguide device and an augmented reality display device to solve the technical problem of color difference in images displayed by existing display devices.

[0006] In a first aspect, this application provides a diffractive optical waveguide device, comprising:

[0007] A substrate, and a coupling grating, a first transition grating, a second transition grating, and a coupling grating disposed on the substrate;

[0008] The first and second folding gratings are arranged in the diffraction direction of the coupling grating, and the distance between the first folding grating and the coupling grating is smaller than the distance between the second folding grating and the coupling grating.

[0009] The coupling grating is disposed in the first turning direction of the first turning grating and in the second turning direction of the second turning grating;

[0010] The first turning angle between the diffraction direction and the first turning direction is in the range of 45°-80°, and the second turning angle between the diffraction direction and the second turning direction is in the range of 10°-45°.

[0011] Optionally, the coupling grating is a two-dimensional array structure.

[0012] Optionally, the coupling gratings are arranged in an array along a first direction and a second direction, wherein the first direction and the second direction are perpendicular to each other.

[0013] Optionally, the sum of the first turning angle and the second turning angle is equal to 90°.

[0014] Optionally, the coupling grating can be a one-dimensional array structure.

[0015] Optionally, both the first and second folding gratings are one-dimensional array structures.

[0016] Optionally, there is a gap between the first folding grating and the second folding grating.

[0017] Optionally, the period of the first folding grating is different from that of the second folding grating, and the directions of the first folding grating and the second folding grating are also different.

[0018] Optionally, the groove shape of the coupling grating can be any one of rectangle, triangle, or tilt.

[0019] In a second aspect, this application provides an augmented reality display device, including any of the diffractive waveguide devices of the first aspect.

[0020] This application provides a diffractive waveguide device and an augmented reality display device. The diffractive waveguide device includes: a substrate, and a coupling grating, a first bend grating, a second bend grating, and a coupling out grating disposed on the substrate. The first bend grating and the second bend grating are disposed in the diffraction direction of the coupling grating, and the distance between the first bend grating and the coupling grating is less than the distance between the second bend grating and the coupling grating. The coupling out grating is disposed in the first bend direction of the first bend grating and is located in the second bend direction of the second bend grating. The first bend angle between the diffraction direction and the first bend direction is in the range of 45°-80°, and the second bend angle between the diffraction direction and the second bend direction is in the range of 10°-45°. In this technical solution, the coupling grating diffracts all red, green, and blue light elements into the first transition grating. The first transition grating diffracts a portion of the red light elements from the first transition direction to the coupling grating according to the light transmission angle. The other portion of the red light elements, due to the larger transmission angle, will continue to diffract to the second transition grating. Then, the second transition grating diffracts this portion of the red light elements from the second transition direction to the coupling grating, thereby ensuring that the coupling grating can couple both portions of the red light elements to the observation end, achieving compensation for the red light elements and reducing the color difference problem in the image at the observation end. Attached Figure Description

[0021] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0022] Figure 1 This is a schematic diagram of the structure of the diffractive waveguide device provided in the embodiments of this application;

[0023] Figure 2 This is a schematic diagram of the structure of the first and second bend gratings in the diffractive waveguide device provided in the embodiments of this application;

[0024] Figure 3 A schematic diagram of the optical transmission path in the diffractive waveguide device provided in the embodiments of this application;

[0025] Figure 4 A schematic diagram of another optical transmission path in the diffractive waveguide device provided in the embodiments of this application;

[0026] Figure 5 A schematic diagram of each grating direction in the diffractive waveguide device provided in the embodiments of this application;

[0027] Figure 6 The image shows the ray tracing results of the diffractive waveguide device provided in the embodiments of this application.

[0028] Figure 7 Another ray tracing simulation result diagram of the diffractive waveguide device provided in the embodiments of this application.

[0029] Figure label:

[0030] 100 - Diffractive waveguide device; 101 - Substrate; 102 - Coupled-in grating; 103 - First transition grating; 104 - Second transition grating; 105 - Coupled-out grating; 1051 - First coupled-out grating; 1052 - Second coupled-out grating.

[0031] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0032] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0033] In existing technologies, the characteristics and design of gratings in diffractive waveguide devices may lead to non-uniform diffraction characteristics under incident light of different wavelengths and angles. This can result in red light loss when the diffractive waveguide device transmits red, green, and blue light. For example, the grating may be optimized for the wavelength range of green or blue light during manufacturing, but the transmission of red light may not be ideal, resulting in the loss or attenuation of red light. This can lead to visual abnormalities such as color difference in the final displayed image.

[0034] To address the problems of existing technologies, the inventors, during their research on the diffraction and propagation of light in diffractive waveguide devices, discovered that when red, green, and blue light elements are coupled into the diffractive waveguide device through a coupling grating, differences in their propagation angle and energy can cause some light energy to continue diffracting along the diffraction direction to the deflection grating, failing to be deflected and propagated to the output grating, resulting in a loss of some light energy. Therefore, after extensive research on the deflection angle of the deflection grating, the inventors discovered that two sets of deflection gratings with different deflection angles can be set. This allows red light elements that cannot be deflected through the first deflection grating to be deflected through the second deflection grating to the output grating at a second deflection angle. Based on this, this solution proposes a deflection grating with two sets of different deflection angles, achieving red light element compensation and reducing color difference problems in the displayed image at the observation end.

[0035] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0036] Figure 1 This is a schematic diagram of the structure of the diffractive waveguide device provided in an embodiment of this application. Figure 1 As shown, the diffractive waveguide device 100 includes:

[0037] Substrate 101, and coupling in grating 102, first transition grating 103, second transition grating 104, and coupling out grating 105 disposed on substrate 101;

[0038] The first folding grating 103 and the second folding grating 104 are disposed in the diffraction direction of the coupling grating 102, and the distance between the first folding grating 103 and the coupling grating 102 is less than the distance between the second folding grating 104 and the coupling grating 102.

[0039] The coupling grating 105 is disposed in the first turning direction of the first turning grating 103 and in the second turning direction of the second turning grating 104.

[0040] The first turning angle between the diffraction direction and the first turning direction is in the range of 45°-80°, and the second turning angle between the diffraction direction and the second turning direction is in the range of 10°-45°.

[0041] The substrate 101 provides a total internal reflection channel for each optical element such as grating in the diffraction waveguide device 100, ensuring that red, green and blue light rays can be transmitted without loss in the substrate 101. At the same time, the substrate 101 also has a mechanical support function, ensuring that the geometry and position of each grating remain stable, thereby ensuring that the performance of the diffraction waveguide device 100 is not affected by external vibration or deformation.

[0042] A grating is an optical element composed of periodically arranged protrusions or depressions. It can diffract incident light of different wavelengths into a reflecting or transmitting medium at a certain angle and with a certain efficiency through the principle of diffraction. For example, in the embodiments of this application, the first folding grating 103 and the second folding grating 104 can be used to change the direction of light propagation, thereby ensuring that all light rays can be diffracted to the coupling grating 105.

[0043] First, the coupling grating 102 is located at the entrance end of the diffractive waveguide device 100, used to couple an external light source to the substrate 101 and diffract the external light source along the diffraction direction into the corresponding transmission path, that is, to the first turning grating 103. In addition, the position of the coupling grating 102 in the diffractive waveguide device 100 will affect the light coupling efficiency, that is, to ensure that the incident light can be effectively coupled to the substrate 101 of the diffractive waveguide device 100. Therefore, when designing the position of the coupling grating 102, it is necessary to consider what specific grating positions or functions the current application scenario of the diffractive waveguide device 100 may require. For example, the diffractive waveguide device 100 may need to achieve efficient coupling at the device entrance, or perform complex light transmission path control and adjustment inside the diffractive waveguide device 100.

[0044] Secondly, in the diffractive waveguide device 100, light usually needs to be transmitted and processed along a complex optical path, while the deflection grating can realize the function of changing the transmission direction of light. That is, the deflection grating can introduce diffracted light at a specific position, so that the light can be deflected inside the diffractive waveguide device 100, thereby enabling the light to be transmitted between different grating channels.

[0045] Specifically, in this embodiment, two sets of folding gratings are provided, namely a first folding grating 103 and a second folding grating 104. By setting the first folding grating 103 in the diffraction direction of the coupling grating 102, it can be ensured that all light rays in the coupling substrate 101 of the coupling grating 102 can be diffracted and transmitted to the first folding grating 103 along its diffraction direction. This ensures that the light rays in the coupling substrate 101 of the coupling grating 102 can be smoothly transmitted to the first folding grating 103, reducing light loss and reflection, and improving light transmission efficiency. In addition, the second folding grating 104 is also set in the diffraction direction of the coupling grating 102, and the first folding grating 104 is also set in the diffraction direction of the coupling grating 102. The distance between the refractive grating 103 and the coupling grating 102 is less than the distance between the second bend grating 104 and the coupling grating 102. The purpose is that the first bend grating 103 and the second bend grating 104 can cooperate to achieve effective splitting of optical signals, so that light can be transmitted and processed according to a preset optical path. In one possible implementation, the first bend grating 103 and the second bend grating 104 can be located in the lower region of the substrate 101, while the coupling grating 105 is located in the upper region of the first bend grating 103 and the second bend grating 104, and is spaced at the same distance from the first bend grating 103 and the second bend grating 104.

[0046] In one feasible approach, the light diffracted from the coupling grating 102 first passes through the first deflection grating 103. The first deflection grating 103 performs a diffraction judgment on the light, that is, it determines whether the incident angle and wavelength of the light meet the diffraction conditions of the first deflection grating 103. When the incident angle and wavelength of the light meet the diffraction angle, the first deflection grating 103 will diffract the light according to the first deflection angle to the coupling grating 105. When the incident angle and wavelength of the light do not meet the diffraction angle, the light will continue along the original coupling grating. The light continues to diffract in the diffraction direction of 102 and enters the second turning grating 104. The second turning grating 104 will adjust its transmission direction again according to the wavelength of the light and the incident angle, and diffract the light into the coupling grating 105 according to the second turning angle. In this embodiment, the first turning angle is set in the range of 45°-80° and the second turning angle is set in the range of 10°-45°, which can ensure that the light diffracted from the first turning angle and the light diffracted from the second turning angle can be coupled into the coupling grating 105 together.

[0047] Optionally, the coupling grating 105 is a two-dimensional array structure.

[0048] Optionally, the coupling grating 105 is arranged in an array along a first direction and a second direction, wherein the first direction and the second direction are perpendicular to each other.

[0049] The two-dimensional array structure enables the coupling grating 105 to achieve more output ports in a limited space. This arrangement utilizes a two-way planar arrangement. Furthermore, the vertical array arrangement in the first and second directions ensures that the two-dimensional array of the coupling grating 105 can be in the first and second turning directions, thereby ensuring that all the coupled light rays can be coupled out in the coupling grating 105, realizing the light supplementation function and reducing the color difference problem of the final coupled light rays.

[0050] Optionally, the sum of the first turning angle and the second turning angle is equal to 90°.

[0051] In this process, after the light rays are diffracted along the diffraction direction to the first turning grating, part of the light rays are turned along the first turning angle to the gratings arranged in the first direction in the coupling grating, while the other part of the light rays continue to diffract to the second turning grating and are turned along the second turning angle to the gratings arranged in the second direction in the coupling grating. This ensures that the diffraction direction, the first turning direction and the second turning direction can form a triangle, ensuring the accuracy and stability of the light propagation path. This makes the angle adjustment of the light rays during the turning and diffraction process more controllable and precise, and minimizes the possibility of optical errors.

[0052] Optionally, the coupling grating 102 is a one-dimensional array structure.

[0053] The one-dimensional array structure allows multiple light waves to be coupled in a relatively small space, and the angle and direction of the incident light can be precisely controlled, thereby ensuring that the light can be effectively coupled into the diffractive waveguide device 100.

[0054] Optionally, the groove shape of the coupling grating 102 can be any one of rectangle, triangle, or tilt.

[0055] In one feasible approach, the slot shape of the coupling grating 102 in the one-dimensional array structure can be rectangular, characterized by its straight sidewalls, which can maintain the shape of the input light and is beneficial for maintaining the light transmission efficiency and directionality; or the slot shape can be triangular, the angle of the triangular slot shape can reduce the reflection and scattering of light on the grating surface, which helps to improve the coupling efficiency and light transmission quality. In addition, for different modes of light, the triangular slot shape can provide more flexible coupling angle selection, thereby adapting to a variety of optical application scenarios; the slot shape of the coupling grating 102 can also be tilted, the tilted slot shape can increase the range of incident angles and reduce losses caused by reflection, thereby improving the light transmission efficiency and stability.

[0056] Optionally, both the first folding grating 103 and the second folding grating 104 are one-dimensional array structures.

[0057] Optionally, the period of the first folding grating 103 is different from that of the second folding grating 104, and the directions of the first folding grating 103 and the second folding grating 104 are also different.

[0058] Since light of different wavelengths has different diffraction effects on gratings of different periods, and the different directions of each grating can lead to different transmission paths and beam separation in the diffractive waveguide device 100, it is very important to design gratings of different periods and directions for the diffractive waveguide device 100 that can process multiple optical signals or frequencies simultaneously.

[0059] In one feasible approach, red, green, and blue light, which have different transmission patterns, have different transmission angles in the diffraction waveguide device 100. Therefore, setting transition gratings with different periods will result in different diffraction angles of different wavelengths of incident light on the grating surface. For red light, transition gratings with different periods can make the red light wavelength have a larger diffraction angle, thereby ensuring that the spectral components of red light can be separated and captured more effectively. In addition, different directions of the grating will also affect the diffraction effect of the incident light. Gratings with different directions can be used to process light signals of different wavelengths separately. For example, the second transition grating 104 can be used specifically to capture information of red light elements, while the first transition grating 103 can be used to process red, green, and blue light elements, thereby improving the capture efficiency of light of different wavelengths and achieving higher precision and more efficient optical signal processing.

[0060] In one feasible approach, the substrate 101 can be a lens. Since the lens has a very high optical surface quality, it can effectively reduce light scattering and reflection, which is beneficial to maintaining the transmission efficiency and stability of the optical waveguide system.

[0061] In another possible implementation, the substrate 101 can be a spectrometer that can use the coupling grating, the first transition grating, the second transition grating, and the coupling grating in the diffraction waveguide device 100 to perform wavelength analysis and measurement on the input optical signal, thereby analyzing the spectral characteristics of the corresponding device.

[0062] The diffractive waveguide device 100 provided in this application embodiment couples incident light into the diffractive waveguide device 100 through a coupling grating 102. By using the different grating periods and directions of the first transition grating 103 and the second transition grating 104, light of different wavelengths or diffraction angles is processed respectively, thereby ensuring that all incident light can be diffracted to the output grating 105, realizing dispersion compensation of the diffractive waveguide device 100, thereby avoiding the introduction of unnecessary time delay or optical signal distortion in the diffractive waveguide device 100.

[0063] Figure 2This is a schematic diagram of the structure of the first and second bend gratings in the diffractive waveguide device provided in the embodiments of this application. Figure 2 As shown, there is a gap between the first folding grating and the second folding grating.

[0064] In the diffractive waveguide device 100, the first transition grating 103 and the second transition grating 104 are adjacent to each other and separated by a gap G, which serves as the boundary region between the two transition gratings. By adjusting the gap G, the diffractive waveguide device 100 can selectively couple and decouple optical signals of specific wavelengths. In addition, by reasonably designing the size of the gap G, problems such as wavelength cross-interference or optical loss that may occur in the diffractive waveguide device 100 can be reduced, thereby improving the stability and reliability of the diffractive waveguide device 100.

[0065] In one feasible approach, the interval G between the first transition grating 103 and the second transition grating 104 can be 0, as long as the directions and periods of the two transition gratings are different. The purpose is to ensure that the optical signal can be transmitted in the corresponding period direction when passing through the first transition grating 103 and the second transition grating 104, thus ensuring that the first transition grating 103 and the second transition grating 104 work independently and do not interfere with each other or affect each other's coupling efficiency and waveguide mode.

[0066] Furthermore, the contour shapes of the first angular grating 103 and the second angular grating 104 are not limited to... Figure 2 The structure shown can be any polygonal structure or a polygonal structure with several rounded corners, as long as its period and direction are different.

[0067] Figure 3 This is a schematic diagram of the optical transmission path in the diffractive waveguide device provided in an embodiment of this application. Figure 3 As shown, a transmission pattern of red, green, and blue light is illustrated in the first deflection grating 103 and the second deflection grating 104.

[0068] By designing the period and direction of the first deflection grating 103 and the second deflection grating 104, the diffraction characteristics of red, green, and blue light rays on the first deflection grating 103 and the second deflection grating 104 can be determined. For example, in one feasible approach, the diffraction waveguide device 100 needs to perform optical compensation for red and green light rays. In this case, the period of the deflection grating needs to be designed according to the wavelengths of the red and green light rays. This includes: calculating the relationship between the deflection grating and the wavelength and incident angle of the incident light, then determining the wavelength range of the red and green light rays, and finally determining the direction and period of the first deflection grating 103 and the second deflection grating 104 based on the wavelength range and the angular relationship.

[0069] In one feasible implementation, the transmission process of red, green, and blue light in the first transition grating 103 and the second transition grating 104 includes: the red, green, and blue light rays are transitioned by the first transition grating, and then only the red light rays are transitioned by the second transition grating 104. Specifically, the red, green, and blue light rays coupled to the substrate 101 by the coupling grating 102, when passing through the first transition grating 103, a portion of the red light rays will continue to diffract along the diffraction direction of the coupling grating 102, and another portion of the red light rays will be transmitted to the coupling grating 105 along the first transition direction. The green and blue light rays will all be transmitted to the coupling grating 105 along the first transition direction. The diffraction direction and the first transition direction are... The angle between the two directions is θ. The red light rays that continue to diffract along the diffraction direction of the coupling grating 102 will continue to diffract into the second turning grating 104. At this time, the second turning grating 104 will transmit the light to the coupling grating 105 along the second turning direction, and the angle between the diffraction direction and the second turning direction is φ. In addition, the sum of the angles θ and φ is 90°, which is related to the two-dimensional array structure that is perpendicular to each other in the coupling grating 105. That is, it is ensured that the light directions that turn from the first turning direction and the second turning direction to the coupling grating 105 are perpendicular to each other, so that the two-dimensional array in the coupling grating 105 can couple out the corresponding light respectively, and finally ensure that the light rays of the coupling diffraction waveguide device 100 meet the diffraction requirements, thus realizing the red light compensation function of the diffraction waveguide device 100.

[0070] Figure 4 This is a schematic diagram of another optical transmission path in the diffractive waveguide device provided in the embodiments of this application. For example... Figure 4 As shown, another transmission pattern of red, green and blue light in the first deflection grating 103 and the second deflection grating 104 is demonstrated.

[0071] The steps for designing the period and direction of the first folding grating 103 and the second folding grating 104 are the same as those in the above embodiments, and will not be repeated in this application embodiment.

[0072] In one feasible approach, the light rays that are deflected by the first deflection grating include three colors: red, green, and blue. The light rays that are deflected by the second deflection grating 104 include only red and green light rays. Specifically, when the red, green, and blue light rays coupled into the substrate 101 through the coupling grating 102 pass through the first deflection grating 103, a portion of the red light rays and a portion of the green light rays continue to diffract along the diffraction direction of the coupling grating 102. Another portion of the red and green light rays are transmitted to the coupling grating 105 along the first deflection direction, while all the blue light rays are transmitted to the coupling grating 105 along the first deflection direction. The angle between the diffraction direction and the first deflection direction is θ. The red light rays that continue to diffract along the diffraction direction of the coupling grating 102 will continue to diffract into the second bend grating 104. At this time, the second bend grating 104 will transmit the light to the coupling grating 105 along the second bend direction, and the angle between the diffraction direction and the second bend direction is φ. In addition, the sum of the angles θ and φ is 90°, which is related to the mutually perpendicular two-dimensional array structure in the coupling grating 105. That is, it is ensured that the light directions bend from the first bend direction and the second bend direction to the coupling grating 105 are mutually perpendicular. This ensures that the compensation effect of the bend grating for red and green light in practical applications meets the expected requirements, and ensures that the diffraction waveguide device 100 has good diffraction characteristics and efficient coupling effect at different wavelengths.

[0073] Figure 5 This is a schematic diagram of the various grating directions in the diffractive waveguide device provided in the embodiments of this application. (See attached diagram.) Figure 5 As shown, the grating shape and orientation of each grating region in the diffractive waveguide device 100 are illustrated by way of example.

[0074] The coupling grating 105 is a two-dimensional array grating, that is, it has a period in two dimensions. It can be represented as a first coupling grating 1051 and a second coupling grating 1052. The period direction of the first coupling grating 1051 is represented by a straight line EA, and the period direction of the second coupling grating 1052 is represented by a straight line AC, AD or DC. The included angle ∠EAD is 90°, which corresponds to the coupling grating 105 proposed in this application being arrayed along the first and second directions, and the first and second directions being perpendicular to each other.

[0075] For example, the coupling period direction of the coupling grating 102 is AB, the period direction of the first folding grating 103 is BC, and the period direction of the second folding grating 104 is BD, forming five intersection points A, B, C, D, and E. The period directions of any two gratings form an angle. For example, the angle between the period directions of the coupling grating 102 and the second folding grating 104 is ∠ABD, the angle between the period directions of the coupling grating 102 and the first folding grating 103 is ∠ABC, and the angle between the period directions of the first folding grating 103 and the second folding grating 104 is ∠DBC.

[0076] Furthermore, the periodic direction angles between the aforementioned gratings satisfy the following angular relationship:

[0077] ∠AED + ∠ADE = 90°

[0078] ∠ABD + ∠BAD + ∠AED = 90°

[0079] ∠ABD + ∠BAD + ∠DCB + ∠DBC = 180°

[0080] Specifically, ∠ABD is less than ∠ABC.

[0081] The first coupling grating 1051 and the second coupling grating 1052 can be interchanged in definition. That is, the periodic direction of the first coupling grating 1051 is EA and the periodic direction of the second coupling grating 1052 is AC, or the periodic direction of the first coupling grating 1051 is AC and the periodic direction of the second coupling grating 1052 is EA.

[0082] Figure 6 The image shows the simulated ray tracing results of the diffractive waveguide device provided in the embodiments of this application. Figure 6 As shown, red, green, and blue light rays are coupled into the substrate 101 through the coupling grating 102 and then diffracted along the diffraction direction of the coupling grating 102 to the first turning grating 103. The first turning grating 103 turns a portion of the red light element, as well as all the blue and green light elements, into the output grating 105 according to the first turning direction. The second turning grating 104 turns the red light element that has not been turned by the first turning grating 103 into the output grating 105 according to the second turning direction. Finally, all the red, green, and blue light elements are coupled out in the output grating 105, realizing the red light compensation function of the diffraction waveguide device 100.

[0083] Figure 7 Another ray tracing simulation result diagram of the diffractive waveguide device provided in the embodiments of this application. (See diagram below.) Figure 7As shown, red, green, and blue light rays are coupled into the substrate 101 through the coupling grating 102, and then diffracted along the diffraction direction of the coupling grating 102 to the first turning grating 103. The first turning grating 103 turns a portion of the red and green light, as well as all the blue light, into the output grating 105 according to the first turning direction. The second turning grating 104 turns the red and green light elements that have not been turned by the first turning grating 103 into the output grating 105 according to the second turning direction. Finally, all the red, green, and blue light elements are coupled out in the output grating 105, realizing the red and green light compensation function of the diffraction waveguide device 100.

[0084] It should be noted that the contour shape, refractive index, and thickness of the substrate 101, the contour shape, period, linewidth, and height of the coupled grating 102, the contour shape, period, linewidth, and height of the first transition grating 103, the contour shape, period, linewidth, and height of the second transition grating 104, and the contour shape, period, unit pattern structure, unit pattern size, and height of the coupled grating 105 in this embodiment are all reasonably designed and will not be repeated in this embodiment.

[0085] This application also proposes an augmented reality display device, including the diffractive waveguide device 100 provided in any of the above embodiments.

[0086] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0087] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to this application.

[0088] In the above embodiments, the descriptions of each embodiment have their own emphasis. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments. The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as these combinations of technical features do not contradict each other, they should be considered within the scope of this specification.

[0089] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0090] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A diffractive optical waveguide device, characterized in that, include: A substrate, and a coupling grating, a first transition grating, a second transition grating, and a coupling grating disposed on the substrate; The first folding grating and the second folding grating are disposed in the diffraction direction of the coupling grating, and the distance between the first folding grating and the coupling grating is less than the distance between the second folding grating and the coupling grating. The coupling grating is disposed in the first turning direction of the first turning grating and in the second turning direction of the second turning grating; The first turning angle between the diffraction direction and the first turning direction is in the range of 45°-80°, and the second turning angle between the diffraction direction and the second turning direction is in the range of 10°-45°.

2. The apparatus according to claim 1, characterized in that, The coupled grating is a two-dimensional array structure.

3. The apparatus according to claim 2, characterized in that, The coupled gratings are arranged in an array along a first direction and a second direction, wherein the first direction and the second direction are perpendicular to each other.

4. The apparatus according to claim 3, characterized in that, The sum of the first turning angle and the second turning angle is equal to 90°.

5. The apparatus according to any one of claims 1-4, characterized in that, The coupling grating is a one-dimensional array structure.

6. The apparatus according to any one of claims 1-4, characterized in that, Both the first and second transition gratings are one-dimensional array structures.

7. The apparatus according to any one of claims 1-4, characterized in that, There is a gap between the first folding grating and the second folding grating.

8. The apparatus according to any one of claims 1-4, characterized in that, The period of the first folding grating is different from that of the second folding grating, and the directions of the first folding grating and the second folding grating are also different.

9. The apparatus according to claim 5, characterized in that, The groove shape of the coupling grating can be any one of rectangle, triangle, or tilt.

10. An augmented reality display device, characterized in that, Includes the diffractive waveguide device as described in any one of claims 1 to 9.

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