Binocular waveguide structure and AR device

Abstract

The utility model provides a binocular waveguide structure and AR equipment, and relates to the technical field of AR display. The binocular waveguide structure comprises a waveguide sheet with an entrance pupil area, a first light path area and a second light path area. Wherein the waveguide sheet is divided into a first waveguide part and a second waveguide part along the central axis, the first optical path area is located on the first waveguide part, the second optical path area is located on the second waveguide part, and the entrance pupil area is partially or completely arranged on the first waveguide part or the second waveguide part; the entrance pupil area, the first light path area and the second light path area are asymmetrically arranged relative to the central axis of the waveguide sheet. The design freedom degree of the optical waveguide structure of the binocular waveguide structure is high, customized design can be achieved, and diversified customer requirements can be met.

Description

Technical Field

[0001] The utility model relates to the technical field of AR display, and in particular to a binocular waveguide structure and an AR device. Background Art

[0002] Augmented Reality (AR) is a new technology that "seamlessly" integrates real-world information and virtual-world information. It uses computers and other scientific technologies to simulate and superimpose physical information that is difficult to experience within a certain time and space range in the real world, and then applies virtual information to the real world, which is perceived by human senses, thereby achieving a sensory experience beyond reality. The real environment and virtual objects are superimposed on the same screen or space in real time and exist simultaneously. AR display systems usually include an optical machine and an optical display screen. The pixels on the micro-display inside the optical machine are projected into the human eye through the optical display screen, and the user can see the real world through the optical display screen. Among them, the optical machine provides virtual content for the device, and the optical display screen is usually a transparent optical component.

[0003] The optical waveguide is a path for realizing the optical path of an optical display screen. When the refractive index of the transmission medium is greater than that of the surrounding medium and the incident angle in the waveguide is greater than the critical angle of total reflection, the light can be transmitted in the optical waveguide without leakage, and total reflection occurs. After the light from the projector is coupled into the optical waveguide, the light continues to propagate the image losslessly in the optical waveguide until it is coupled out by the subsequent structure. At present, the optical waveguides on the market are generally divided into geometric array optical waveguides and diffraction optical waveguides. Among them, the diffraction optical waveguide has become the mainstream choice in the current AR field because of its advantages such as low process difficulty and large-scale mass production. The existing diffraction optical waveguide structure includes a single-input dual-output waveguide structure, that is, a grating structure with one entrance pupil area corresponding to two exit pupil areas. Only one input light source is required, and the output images of the two exit pupil areas can reach both eyes at the same time. However, the entrance pupil area in the existing single-input dual-output waveguide structure is designed to be located at the horizontal center of the entire optical waveguide and slightly above the vertical direction, and the exit pupil and the expanded pupil are symmetrically distributed on both sides of the entrance pupil. In AR devices, the use of a single-input, dual-output symmetrical optical waveguide structure design reduces the design freedom of the optical waveguide structure, making it difficult to achieve customized design and meet diverse customer needs. Utility Model Content

[0004] The purpose of the utility model is to provide a binocular waveguide structure and an AR device. The binocular waveguide structure and the optical waveguide structure of the AR device have a high degree of freedom in design, can realize customized design, and can meet diverse customer needs.

[0005] The embodiment of the utility model is achieved as follows:

[0006] In one aspect of the utility model, a binocular waveguide structure is provided, the binocular waveguide structure comprises a waveguide plate having an entrance pupil area, a first optical path area and a second optical path area; wherein the waveguide plate is divided into a first waveguide portion and a second waveguide portion along a central axis, the first optical path area is located on the first waveguide portion, the second optical path area is located on the second waveguide portion, and the entrance pupil area is partially or completely arranged on the first waveguide portion or the second waveguide portion; the entrance pupil area, the first optical path area and the second optical path area are arranged asymmetrically relative to the central axis of the waveguide plate. The optical waveguide structure of the binocular waveguide structure has a high degree of design freedom, can realize customized design, and can meet diverse customer needs.

[0007] Optionally, the first optical path area includes a first exit pupil area and M first expanded pupil areas, and the second optical path area includes a second exit pupil area and N second expanded pupil areas, M and N are respectively greater than or equal to 0; a first exit pupil grating is provided on the first exit pupil area, and when M is greater than 0, a first expanded pupil grating is provided on the first expanded pupil area; a second exit pupil grating is provided on the second exit pupil area, and when N is greater than 0, a second expanded pupil grating is provided on the second expanded pupil area.

[0008] Optionally, the first exit pupil grating and the second exit pupil grating both adopt two-dimensional gratings, and M and N are both equal to 0; the center of the entrance pupil area does not coincide with the central axis of the waveguide; or, any one of the area, shape and structure of the first exit pupil grating and the second exit pupil grating is different; or, the first exit pupil grating and the second exit pupil grating are asymmetrically arranged relative to the central axis of the waveguide.

[0009] Optionally, the first exit pupil grating adopts a one-dimensional grating, the second exit pupil grating adopts a two-dimensional grating, M is greater than 0 and N is equal to 0; or, the first exit pupil grating adopts a two-dimensional grating, the second exit pupil grating adopts a one-dimensional grating, N is greater than 0 and M is equal to 0.

[0010] Optionally, the angle between two grating directions of the two-dimensional grating is between 10° and 90°.

[0011] Optionally, the first exit pupil grating and the second exit pupil grating both adopt one-dimensional gratings, and M and N are both greater than 0; the center of the entrance pupil area does not coincide with the central axis of the waveguide; or, any one of the area, shape and structure of the first exit pupil grating and the second exit pupil grating is different; or, the first exit pupil grating and the second exit pupil grating are asymmetrically arranged relative to the central axis of the waveguide; or, any one of the number, shape, area and structure of the first pupil expansion grating and the second pupil expansion grating is different; or, the first pupil expansion grating and the second pupil expansion grating are asymmetrically arranged relative to the central axis of the waveguide.

[0012] Optionally, the distance between the center of the first exit pupil area and the center of the second exit pupil area is between 56 mm and 70 mm.

[0013] Optionally, the material of the waveguide plate is glass or resin.

[0014] Optionally, a diffraction grating is used in the entrance pupil area.

[0015] Another aspect of the present invention provides an AR device, which includes an optical machine and the above-mentioned binocular waveguide structure.

[0016] The beneficial effects of the utility model include:

[0017] The binocular waveguide structure provided by the present application includes a waveguide plate having an entrance pupil area, a first optical path area, and a second optical path area; wherein the waveguide plate is divided into a first waveguide portion and a second waveguide portion along the central axis, the first optical path area is located on the first waveguide portion, the second optical path area is located on the second waveguide portion, and the entrance pupil area is partially or completely arranged on the first waveguide portion or the second waveguide portion; the entrance pupil area, the first optical path area, and the second optical path area are asymmetrically arranged relative to the central axis of the waveguide plate. The present application arranges the entrance pupil area, the first optical path area, and the second optical path area asymmetrically relative to the central axis of the waveguide plate, so that the entrance pupil area, the first optical path area, and the second optical path area can be changed according to different design requirements (for example, the area, shape, grating structure, position, quantity, etc. of the corresponding area can be changed), thereby achieving a higher degree of design freedom, achieving the purpose of diversified customization, and being able to meet diverse customer needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 One of the structural schematic diagrams of the binocular waveguide structure of the first embodiment provided by the utility model;

[0020] Figure 2 The second structural schematic diagram of the binocular waveguide structure of the first embodiment provided by the utility model;

[0021] Figure 3 The third structural diagram of the binocular waveguide structure of the first embodiment provided by the utility model;

[0022] Figure 4 for Figure 3 Wave vector path diagram of ;

[0023] Figure 5 A schematic diagram of the structure of the binocular waveguide structure of the second embodiment provided by the utility model;

[0024] Figure 6 for Figure 5 A wave vector path diagram of a first output optical path;

[0025] Figure 7 for Figure 5 A wave vector path diagram of a second output optical path;

[0026] Figure 8 A schematic structural diagram of a binocular waveguide structure of a third embodiment provided by the utility model;

[0027] Fig. 9 for Figure 8 A wave vector path diagram of a first output optical path;

[0028] Fig.10 for Figure 8 A wave vector path diagram of a second output optical path;

[0029] Fig.11 A schematic structural diagram of a binocular waveguide structure of a fourth embodiment provided by the utility model;

[0030] Fig.12 for Fig.11 A wave vector path diagram of a first output optical path;

[0031] Fig.13 for Fig.11 A wave vector path diagram of a second output optical path;

[0032] Fig.14 A schematic structural diagram of a binocular waveguide structure of a fifth embodiment provided by the utility model;

[0033] Fig.15 for Fig.14 A wave vector path diagram of a first output optical path;

[0034] Fig.16 for Fig.14 Wave vector path diagram of the second output optical path.

[0035] Icons: 10-waveguide; 11-entrance pupil area; 12-first optical path area; 121-first exit pupil area; 122-first expanded pupil area; 13-second optical path area; 131-second exit pupil area; 132-second expanded pupil area; 14-first waveguide section; 15-second waveguide section; 200-optical machine. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0039] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0040] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0041] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] The existing diffraction optical waveguide structure includes a single-input dual-output waveguide structure, that is, one entrance pupil area corresponds to two exit pupil areas. In this way, only one input light source is required, and the output images of the two exit pupil areas can reach both eyes at the same time. However, in the existing single-input dual-output waveguide structure, the single entrance pupil area is usually designed to be located at the horizontal center of the entire waveguide sheet, slightly above the vertical direction, and the exit pupil area and the pupil expansion area are symmetrically distributed on the opposite sides of the entrance pupil area. In this way, the design freedom of using a single-input dual-output symmetrical waveguide structure in an AR device is low, and it is impossible to achieve the diversification of the binocular waveguide grating shape, nor to achieve customized design, and it is difficult to meet the diverse needs of customers. To this end, the present application provides a new binocular waveguide structure, which can increase the design freedom to achieve customized design of the grating structure, thereby meeting the different needs of various users. The specific structure of the new binocular waveguide structure will be described in detail below.

[0043] Please refer to Figures 1 to 4 This embodiment provides a binocular waveguide structure, which includes a waveguide plate 10 having an entrance pupil area 11, a first optical path area 12, and a second optical path area 13; wherein the waveguide plate 10 is divided into a first waveguide portion 14 and a second waveguide portion 15 along the central axis, the first optical path area 12 is located on the first waveguide portion 14, the second optical path area 13 is located on the second waveguide portion 15, and the entrance pupil area 11 is partially or completely arranged on the first waveguide portion 14 or the second waveguide portion 15; the entrance pupil area 11, the first optical path area 12, and the second optical path area 13 are asymmetrically arranged relative to the central axis of the waveguide plate 10. The optical waveguide structure of the binocular waveguide structure has a high degree of design freedom, can realize customized design, and can meet diverse customer needs.

[0044] In this embodiment, if Figure 2 and Figure 3 As shown, after the incident light is coupled into the waveguide plate 10 from the entrance pupil area 11, it is totally reflected and propagated in the direction of the first waveguide portion 14 and the direction of the second waveguide portion 15 respectively, wherein a part of the light is coupled out of the waveguide plate 10 through the first optical path area 12 to form a first output light, and another part of the light is coupled out of the waveguide plate 10 through the second optical path area 13 to form a second output light, and the first image formed by the first output light and the second image formed by the second output light overlap at infinity.

[0045] The binocular waveguide structure comprises a waveguide plate 10, wherein the waveguide plate 10 has an entrance pupil area 11, a first optical path area 12 and a second optical path area 13. Figure 1 and Figure 2As shown. It should be noted that the binocular waveguide structure can cooperate with the optical machine 200 to form the core architecture of the augmented reality display device, output the virtual content in front of the user, and superimpose it with the reality to form an augmented reality effect. At the same time, since the entrance pupil area 11, the first light path area 12 and the second light path area 13 of the binocular waveguide structure of the present application are asymmetrically arranged relative to the central axis of the waveguide sheet 10, the binocular waveguide structure of the present application can diversify the grating shape of the binocular waveguide structure, realize asymmetric design and customized design, and improve the degree of freedom of design.

[0046] The waveguide sheet 10 is divided into a first waveguide portion 14 and a second waveguide portion 15 along the central axis. Figure 1 and Figure 2 As shown, the first optical path area 12 and the second optical path area 13 are respectively located on the first waveguide portion 14 and the second waveguide portion 15 in a one-to-one correspondence, and part or all of the entrance pupil area 11 is located on the first waveguide portion 14 or the second waveguide portion 15.

[0047] Part or all of the entrance pupil area 11 is located on the first waveguide portion 14 or the second waveguide portion 15. It can be that a part of the entrance pupil area 11 is located on the first waveguide portion 14 and the other part is located on the second waveguide portion 15; or, the entire entrance pupil area 11 is located on the first waveguide portion 14; or, the entire entrance pupil area 11 is located on the second waveguide portion 15.

[0048] Also, optionally, the material of the waveguide sheet 10 can be glass or resin. The reason for using glass or resin is that glass or resin has a certain refractive index and good optical properties, which can provide good conditions for the propagation of light. Of course, if there are other materials with similar properties, they can also be used to make the waveguide sheet 10.

[0049] It should be noted that an entrance pupil grating is provided on the entrance pupil area 11. The commonly used diffraction grating types in the AR field are surface relief grating and volume holographic grating. Among them, the surface relief grating has a very high degree of design freedom. In addition, the nanoimprint process technology used to make the surface relief grating is relatively mature. Therefore, in this embodiment, it is preferred that the entrance pupil area 11 adopts a surface relief grating.

[0050] In addition, the grating type of the entrance pupil grating of the entrance pupil region 11 can be a one-dimensional grating or a two-dimensional grating. The one-dimensional grating has a higher coupling efficiency than the two-dimensional grating, but the two-dimensional grating can expand the image in two dimensions. For the entrance pupil region 11, usually only a one-dimensional grating is needed.

[0051] A first grating is provided on the first optical path region 12, and a second grating is provided on the second optical path region 13, wherein the first grating should at least include a first exit pupil grating, and on this basis, it can also include a plurality of first pupil expansion gratings. The second grating should at least include a second exit pupil grating, and on this basis, it can also include a plurality of second pupil expansion gratings.

[0052] In this embodiment, the entrance pupil region 11, the first optical path region 12, and the second optical path region 13 are asymmetrically arranged relative to the central axis of the waveguide plate 10. The asymmetrical distribution arrangement can be specifically manifested as the center line of the entrance pupil region 11 not coinciding with the central axis of the waveguide plate 10. For example, the entrance pupil region 11 is partially deviated from the central axis, completely deviated from the central axis, or has a single-sided entrance pupil.

[0053] Alternatively, the first optical path region 12 and the second optical path region 13 are different in area, shape, position, grating structure, expansion dimension, etc. For example, the area, expansion dimension, shape, grating structure, position, etc. of the bilateral exit pupil regions (the first exit pupil region 121 and the second exit pupil region 131) are inconsistent, and the area, shape, grating structure, position, number, etc. of the bilateral pupil expansion regions (the first pupil expansion region 122 and the second pupil expansion region 132) are inconsistent.

[0054] In summary, the binocular waveguide structure provided in the present application includes a waveguide plate 10 having an entrance pupil area 11, a first optical path area 12 and a second optical path area 13; wherein the waveguide plate 10 is divided into a first waveguide portion 14 and a second waveguide portion 15 along the central axis, the first optical path area 12 is located on the first waveguide portion 14, the second optical path area 13 is located on the second waveguide portion 15, and the entrance pupil area 11 is partially or completely arranged in the first waveguide portion 14 or the second waveguide portion 15; the entrance pupil area 11, the first optical path area 12 and the second optical path area 13 are asymmetrically arranged relative to the central axis of the waveguide plate 10. The present application arranges the entrance pupil area 11, the first light path area 12 and the second light path area 13 asymmetrically relative to the central axis of the waveguide plate 10. In this way, the entrance pupil area 11, the first light path area 12 and the second light path area 13 can be changed according to different design requirements (for example, the area, shape, grating structure, position, number, etc. of the corresponding areas can be changed), thereby achieving a higher degree of design freedom, achieving the purpose of diversified customization, and being able to meet diverse customer needs.

[0055] Optionally, the first optical path area 12 includes a first exit pupil area 121 and M first dilated pupil areas 122, and the second optical path area 13 includes a second exit pupil area 131 and N second dilated pupil areas 132, where M and N are respectively greater than or equal to 0; a first exit pupil grating is provided on the first exit pupil area 121, and when M is greater than 0, a first dilated pupil grating is provided on the first dilated pupil area 122; a second exit pupil grating is provided on the second exit pupil area 131, and when N is greater than 0, a second dilated pupil grating is provided on the second dilated pupil area 132.

[0056] That is to say, the first optical path area 12 at least includes a first exit pupil area 121, and on this basis may also include a plurality of first dilated pupil areas 122 or no first dilated pupil area 122 is set; similarly, the second optical path area 13 at least includes a second exit pupil area 131, and on this basis may also include a plurality of second dilated pupil areas 132 or no second dilated pupil area 132 is set.

[0057] Optionally, in this embodiment, the distance between the center of the first exit pupil area 121 and the center of the second exit pupil area 131 is between 56 mm and 70 mm. In this way, the center distance between the first exit pupil area 121 and the second exit pupil area 131 matches the entrance pupil distance of the human eye pupil.

[0058] It should be noted that the first exit pupil area 121 and the second exit pupil area 131 can be provided with a one-dimensional grating or a two-dimensional grating, depending on actual needs. Figure 1 and Figure 2 In the structure shown, the first exit pupil area 121 and the second exit pupil area 131 both use a two-dimensional grating. It should be noted that the two-dimensional grating can be considered as a one-dimensional grating containing two directions. Optionally, the angle between the two grating directions of the two-dimensional grating is between 10° and 90°. The two-dimensional grating can simultaneously realize the exit pupil and the two-dimensional pupil expansion.

[0059] When the exit pupil grating of the single-side exit pupil area (the first exit pupil grating of the first exit pupil area 121 or the second exit pupil grating of the second exit pupil area 131) adopts a two-dimensional grating, the two-dimensional grating can be directly printed, or one-dimensional gratings in two directions can be double-sidedly printed to be equivalent to one two-dimensional grating. The advantage of the double-sided printing of one-dimensional gratings over the direct printing of two-dimensional gratings is that the difficulty and yield of making two one-dimensional gratings are better than directly making one two-dimensional grating.

[0060] In addition, the exit pupil grating of the single-sided exit pupil area (the first exit pupil grating of the first exit pupil area 121 or the exit pupil grating of the second exit pupil area 131) may also use only a one-dimensional grating. When the exit pupil grating of the single-sided exit pupil area only uses a one-dimensional grating, in order to meet the needs of image expansion, one or more pupil expansion areas with pupil expansion gratings may be provided between the entrance pupil area 11 and the exit pupil grating of the corresponding single-sided exit pupil area (for example, if the first exit pupil grating of the first exit pupil area 121 uses a one-dimensional grating, one or more first pupil expansion gratings may be provided between the entrance pupil grating and the first exit pupil grating; if the second exit pupil grating of the second exit pupil area 131 uses a one-dimensional grating, one or more second pupil expansion gratings may be provided between the entrance pupil grating and the second exit pupil grating).

[0061] In this embodiment, when the first optical path area 12 includes a first exit pupil area 121 and M first dilated pupil areas 122, and the second optical path area 13 includes a second exit pupil area 131 and N second dilated pupil areas 132, the entrance pupil area 11, the first optical path area 12 and the second optical path area 13 are asymmetrically arranged relative to the central axis of the waveguide plate 10. The entrance pupil area 11 may be partially deviated from the central axis, completely deviated from the central axis, or have a single-sided entrance pupil; any one or more of the area, expansion dimension, shape, grating structure, and position of the first exit pupil area 121 and the second exit pupil area 131 may be different; any one or more of the area, shape, grating structure, position, and number of the first dilated pupil area 122 and the second dilated pupil area 132 may be different.

[0062] Exemplarily, in a first feasible implementation, optionally, the first exit pupil grating and the second exit pupil grating both adopt two-dimensional gratings, and M and N are both equal to 0; the center of the entrance pupil area 11 does not coincide with the central axis of the waveguide plate 10; or, any one of the area, shape and structure of the first exit pupil grating and the second exit pupil grating is different; or, the first exit pupil grating and the second exit pupil grating are asymmetrically arranged relative to the central axis of the waveguide plate 10.

[0063] That is, when both the first exit pupil grating and the second exit pupil grating adopt two-dimensional gratings, the entrance pupil area 11 can be partially deviated from the central axis, completely deviated from the central axis, or a single-sided entrance pupil; or, the first exit pupil grating and the second exit pupil grating are different in any one of area, shape and structure; or, the first exit pupil grating and the second exit pupil grating are asymmetrically arranged relative to the central axis of the waveguide plate 10.

[0064] In a second feasible implementation, optionally, the first exit pupil grating adopts a one-dimensional grating, the second exit pupil grating adopts a two-dimensional grating, M is greater than 0 and N is equal to 0; or, the first exit pupil grating adopts a two-dimensional grating, the second exit pupil grating adopts a one-dimensional grating, N is greater than 0 and M is equal to 0.

[0065] That is, one of the first exit pupil grating and the second exit pupil grating is a one-dimensional grating and the other is a two-dimensional grating. In this case, the grating expansion dimensions of the first exit pupil area 121 and the second exit pupil area 131 are different, and the entrance pupil area 11, the first optical path area 12 and the second optical path area 13 are asymmetrically arranged relative to the central axis of the waveguide plate 10. On this basis, one or more of the area, shape, and grating structure of the first exit pupil area 121 and the second exit pupil area 131 may also be different, and the first exit pupil grating and the second exit pupil grating may also be asymmetrically arranged relative to the central axis of the waveguide plate 10.

[0066] In a third feasible implementation, optionally, the first exit pupil grating and the second exit pupil grating both adopt one-dimensional gratings, and M and N are both greater than 0; the center of the entrance pupil area 11 does not coincide with the central axis of the waveguide plate 10; or, any one of the area, shape and structure of the first exit pupil grating and the second exit pupil grating is different; or, the first exit pupil grating and the second exit pupil grating are asymmetrically arranged relative to the central axis of the waveguide plate 10; or, any one of the number, shape, area and structure of the first pupil expansion grating and the second pupil expansion grating is different; or, the first pupil expansion grating and the second pupil expansion grating are asymmetrically arranged relative to the central axis of the waveguide plate 10.

[0067] That is, when the first exit pupil grating and the second exit pupil grating both adopt one-dimensional gratings, the first light path area 12 is correspondingly provided with a first pupil expansion area 122, and the second light path area 13 is correspondingly provided with a second pupil expansion area 132. At this time, the asymmetric arrangement of the entrance pupil area 11, the first light path area 12, and the second light path area 13 relative to the central axis of the waveguide plate 10 can be manifested as satisfying at least one of the following conditions: the center of the entrance pupil area 11 does not coincide with the central axis of the waveguide plate 10; or, any one of the area, shape, and structure of the first exit pupil grating and the second exit pupil grating is different; or, the first exit pupil grating and the second exit pupil grating are asymmetric relative to the central axis of the waveguide plate 10; or, any one of the number, shape, area, and structure of the first pupil expansion grating and the second pupil expansion grating is different; or, the first pupil expansion grating and the second pupil expansion grating are asymmetric relative to the central axis of the waveguide plate 10. The above-mentioned multiple types of conditions can meet any one or more, and the present application does not limit this.

[0068] The following will use different examples to show that the entrance pupil region 11 , the first light path region 12 , and the second light path region 13 are arranged asymmetrically relative to the central axis of the waveguide plate 10 .

[0069] First embodiment

[0070] The schematic diagram of this embodiment is as follows Figures 1 to 3As shown, the entrance pupil area 11 is located on the left side (or right side) of the central axis of the waveguide plate 10, and the first exit pupil area 121 and the second exit pupil area 131 both use a two-dimensional grating, and the angle between the two grating directions of the two-dimensional grating is set to 60°. The optical machine 200 emits light with image information, which is coupled from the entrance pupil area 11 into the optical waveguide for total reflection propagation, and reaches the first exit pupil area 121 on the left and the second exit pupil area 131 on the right, respectively, and then coupled out of the optical waveguide from the two exit pupil areas, and the coupled image is rectangular.

[0071] Figure 4 yes Figures 1 to 3 The K-space diagram of the first output optical path of the binocular waveguide structure shown, K-space refers to the wave vector space. Figure 4 The K space shown is divided into two medium surfaces, n1 and n2, where n1 and n2 represent the refractive index outside the waveguide 10 and the waveguide 10 itself, respectively. The space inside the small circle represents the space with a refractive index of n1, which is usually air. The space between the large circle and the small circle represents the space with a refractive index of n2. Light propagates in the two medium surfaces. If it exceeds the space of the large circle, it means that the light has leaked from the waveguide 10 or does not exist. The square frame in the figure represents the projection of the light field in the K space. The state of light propagating from outside the waveguide 10 to the entrance pupil area 11 is frame 1. After diffraction in the entrance pupil area 11, it is coupled into the waveguide 10 and propagates by total reflection. At this time, the projection of the light field in the K space is frame 2. After multiple total reflections, it touches the exit pupil area and diffraction occurs. Figure 3 The bilateral exit pupil area in is a two-dimensional grating area. Therefore, the projection of the light field in K space quickly experiences the process of moving from box 2 to box 3 and box 3' and then back to box 1, that is, the final input and output wave vector directions are consistent. The reason for this design is to ensure that the final output light does not produce serious dispersion. The K space diagram of the second output light path is consistent with that of the first output light path.

[0072] It should be noted that the first output light path is the path from the entrance pupil area 11 to the first light path area 12, and the second output light path is the path from the entrance pupil area 11 to the second light path area 13, and the same applies to the following embodiments.

[0073] It should be noted that after diffraction in the entrance pupil area 11, the projection of the light field in the K space is transferred from box 1 to box 2, and then propagates to the exit pupil areas on both sides. Gratings in two directions are set in the exit pupil areas on both sides. Some light rays touch the first direction first, and some light rays touch the second direction first, so they appear as two paths in the K space. After the light rays pass through the pupil expansion in two directions, they are coupled out from the exit pupil area, and finally achieve the result of single input and dual output.

[0074] Second embodiment

[0075] The schematic diagram of this embodiment is as follows Figure 5 As shown, the second exit pupil area 131 is a two-dimensional grating. Different from the previous embodiment, the entrance pupil area 11 is placed on the leftmost side of the waveguide plate 10, the first exit pupil area 121 adopts a one-dimensional grating, and a first pupil expansion area 122 is set between the entrance pupil and the first exit pupil area 121. The light is coupled from the entrance pupil area 11 into the optical waveguide for total reflection propagation. After multiple total reflections, it first reaches the first pupil expansion area 122. The first pupil expansion area 122 guides the light to the first exit pupil area 121 and couples out of the optical waveguide to form a left eye image. Part of the light continues to propagate from the first pupil expansion to the second exit pupil area 131, and the light is coupled out of the optical waveguide from the second exit pupil area 131 to form a right eye image. At this point, the result of single input and dual output is completed.

[0076] The wave vector path from the entrance pupil area 11 to the unilateral exit pupil area is shown in Figure 6 and Figure 7 As shown. For the first output optical path, Figure 6 As shown, after diffraction in the entrance pupil area 11, the projection of the light field in the K space is transferred from box 1 to box 2, and then propagates to the first pupil expansion area 122. The first pupil expansion area 122 deflects the light toward the first exit pupil area 121, and the projection of the light field in the K space is transferred to box 3. The light is totally reflected to the first exit pupil area 121 and coupled out to form an image. At this time, the light field is projected as box 1. So far, the projection of the light field in the K space has rapidly experienced the process of moving from box 2 to box 3 and then back to box 1.

[0077] For the second output optical path, Figure 7 As shown, after diffraction in the entrance pupil area 11, the projection of the light field in the K space is transferred from box 1 to box 2, and then propagates to the second exit pupil area 131 after multiple total reflections. The second exit pupil area 131 is a two-dimensional grating area. Some light rays first touch the first direction, and some light rays first touch the second direction. Therefore, there are two paths in the K space. The projection of the corresponding light field in the K space is transferred to box 3 and box 3'. Finally, the light is coupled out from the second exit pupil area 131 to form an image, and the projection of the light field in the k space returns to box 1. So far, the projection of the light field of the second output light path in the K space quickly experiences the process of moving from box 2 to box 3 and box 3' and then back to box 1. The images of the left and right eyes at the infinite position overlap, corresponding to the projection of the light field in the exit pupil area in the k space returns to the position of box 1.

[0078] Third embodiment

[0079] The schematic diagram of this embodiment is as follows Figure 8As shown, the overall architecture is different from the above-mentioned embodiment, but it complies with the principle of high degree of freedom and diversified customization. The entrance pupil area 11 is located on the central axis of the waveguide plate 10, the first exit pupil area 121 adopts a one-dimensional grating, and two first pupil expansion areas 122 are arranged between the optical path from the entrance pupil area 11 to the first exit pupil area 121. The second exit pupil area 131 also adopts a one-dimensional grating, and a second pupil expansion area 132 is arranged on the optical path from the entrance pupil area 11 to the second exit pupil area 131. The light is coupled from the entrance pupil area 11 into the optical waveguide for total reflection propagation, and after multiple total reflection propagation, it reaches the first pupil expansion area 122 to the left, and then propagates through the two first pupil expansion areas 122 in turn, and then propagates to the left to the first exit pupil area 121. The light is coupled out of the optical waveguide from the first exit pupil area 121 to form an image. The light is coupled from the entrance pupil area 11, propagates to the right to the second pupil expansion area 132, and propagates to the second exit pupil area 131 through the second pupil expansion area 132. The light is coupled out of the optical waveguide from the second exit pupil area 131 to form an image. At this point, the result of single input and dual output is completed.

[0080] The wave vector path diagrams of the first output light path and the second output light path from the entrance pupil area 11 to the single-sided exit pupil area are as follows: Fig. 9 and Fig.10 As shown. For the first output optical path, Fig. 9 , after diffraction in the entrance pupil area 11, the projection of the light field in the K space is transferred from box 1 to box 2, and then propagates to one of the first pupil expansion areas 122, and the projection of the light field in the K space is transferred to box 3. The light passes through one first pupil expansion area 122 and is deflected to another first pupil expansion area 122, so the projection of the light field in the K space is transferred to box 4. Finally, the light is totally reflected and propagates to the first exit pupil area 121 and is coupled out to form an image. At this time, the light field is projected back to box 1. At this point, the projection of the light field of the first output optical path in the K space quickly experiences the process of moving from box 2 to box 3, then to box 4, and finally back to box 1.

[0081] For the second output optical path, Fig.10 , after diffraction in the entrance pupil area 11, the projection of the light field in the K space is transferred from frame 1 to frame 2, and then propagates to the second pupil expansion area 132, and the projection of the light field in the K space is transferred to frame 3. The light passes through the second pupil expansion area 132 and is deflected to the second exit pupil area 131 and coupled out to form an image, and the projection of the light field in the k space returns to frame 1. So far, the projection of the light field of the second output light path in the K space quickly experiences the process of moving from frame 2 to frame 3 and then back to frame 1. The images of the left and right eyes at the infinite position overlap, and the projection of the light field in the corresponding exit pupil area in the k space returns to the position of frame 1.

[0082] Fourth embodiment

[0083] The schematic diagram of this embodiment is as follows Fig.11 As shown, the overall architecture is different from the above-mentioned embodiment, but it complies with the principle of high design and diversified customization. The entrance pupil area 11 is located in the middle of the waveguide plate 10, the first exit pupil area 121 on the left side adopts a one-dimensional grating, and two first pupil expansion areas 122 are set between the optical path from the entrance pupil area 11 to the first exit pupil area 121. The second exit pupil area 131 on the right side adopts a two-dimensional grating, and no pupil expansion area is set on the optical path from the entrance pupil area 11 to the second exit pupil area 131. The light is coupled from the entrance pupil area 11 into the optical waveguide for total reflection propagation, and after multiple total reflections, it propagates to the left to the first first pupil expansion area 122, and then propagates to the second first pupil expansion area 122 through the first pupil expansion area 122, and then propagates to the left to the first exit pupil area 121 after expansion through the second first pupil expansion area 122. The light is coupled out of the optical waveguide from the first exit pupil area 121 to form an image. The light is coupled from the entrance pupil area 11 and propagates rightward to the second exit pupil area 131. After the pupil is expanded in two directions of the second exit pupil area 131, the light is coupled out of the optical waveguide from the second exit pupil area 131 to form an image. At this point, the result of single input and dual output is completed.

[0084] The wave vector path diagrams of the first output light path and the second output light path from the entrance pupil area 11 to the single-sided exit pupil area are as follows: Fig.12 and Fig.13 As shown. For the first output optical path, Fig.12 , after diffraction in the entrance pupil area 11, the projection of the light field in the K space is transferred from box 1 to box 2, and then propagates to the first first pupil expansion area 122, and the projection of the light field in the K space is transferred to box 3. The light passes through the first first pupil expansion area 122 and is deflected to the second first pupil expansion area 122, so the projection of the light field in the k space is transferred to box 4. Finally, the light is totally reflected and propagates to the first exit pupil area 121 and is coupled out to form an image. At this time, the light field is projected back to box 1. At this point, the projection of the light field of the first output optical path in the K space quickly experiences the process of moving from box 2 to box 3 and then to box 4, and finally returning to box 1.

[0085] For the second output optical path, Fig.13, after diffraction in the entrance pupil area 11, the projection of the light field in the K space is transferred from frame 1 to frame 2, and then propagates to the second exit pupil area 131 after multiple total reflections. The second exit pupil area 131 is a two-dimensional grating area. Some light rays first touch the first direction, and some light rays first touch the second direction. Therefore, there are two paths in the K space. The projection of the corresponding light field in the K space is transferred to frame 3 and frame 3'. Finally, the light is coupled out from the second exit pupil area 131 to form an image, and the projection of the light field in the k space returns to frame 1. So far, the projection of the light field of the second output optical path in the K space quickly experiences the process of moving from frame 2 to frame 3 and frame 3' and then back to frame 1. The images of the left and right eyes at the infinite position overlap, corresponding to the projection of the light field in the exit pupil area in the k space returns to the position of frame 1.

[0086] Fifth embodiment

[0087] The schematic diagram of this embodiment is as follows Fig.14 As shown, the overall architecture is different from the above-mentioned embodiment, but it complies with the principle of high design and diversified customization. The entrance pupil area 11 is located on the central axis of the waveguide plate 10, and the first exit pupil area 121 on the left side adopts a one-dimensional grating, and a first pupil expansion area 122 is set between the optical path from the entrance pupil area 11 to the first exit pupil area 121. The second exit pupil area 131 on the right side adopts a two-dimensional grating, and no pupil expansion area is set on the optical path from the entrance pupil area 11 to the second exit pupil area 131. The light is coupled from the entrance pupil area 11 into the optical waveguide for total reflection propagation, and after multiple total reflections, it propagates to the first pupil expansion area 122 to the left, and propagates to the first exit pupil area 121 through the first pupil expansion area 122. The light is coupled out of the optical waveguide from the first exit pupil area 121 to form an image. The light is coupled from the entrance pupil area 11, propagates to the right to the second exit pupil area 131, and the light is coupled out of the optical waveguide from the second exit pupil area 131 to form an image. At this point, the result of single input and dual output is completed.

[0088] The wave vector path diagrams of the first output light path and the second output light path from the entrance pupil area 11 to the single-sided exit pupil area are as follows: Fig.15 and Fig.16 As shown. For the first output optical path, Fig.15 As shown, after diffraction in the entrance pupil area 11, the projection of the light field in the K space is transferred from frame 1 to frame 2, and then propagates to the first pupil expansion area 122. The projection of the light field in the K space is transferred to frame 3. The light is deflected by the first pupil expansion area 122 and propagates through multiple total reflections to the first exit pupil area 121 and is coupled out to form an image. At this time, the light field is projected back to frame 1. At this point, the projection of the light field of the first output light path in the K space quickly experiences a process of moving from frame 2 to frame 3 and then back to frame 1.

[0089] For the second output optical path, Fig.16As shown, after diffraction in the entrance pupil area 11, the projection of the light field in the K space is transferred from box 1 to box 2, and then propagates to the second exit pupil area 131 after multiple total reflections. The second exit pupil area 131 is a two-dimensional grating area. Some light rays first touch the first direction, and some light rays first touch the second direction. Therefore, there are two paths in the K space. The projection of the corresponding light field in the K space is transferred to box 3 and box 3'. Finally, the light is coupled out from the second exit pupil area 131 to form an image, and the projection of the light field in the k space returns to box 1. So far, the projection of the light field of the second output light path in the K space quickly experiences the process of moving from box 2 to box 3 and box 3' and then back to box 1. The images of the left and right eyes at the infinite position overlap, and the projection of the light field in the corresponding exit pupil area in the k space returns to the position of box 1.

[0090] Another aspect of the utility model provides an AR device, which includes an optical machine 200 and the above-mentioned binocular waveguide structure. Among them, the light with image information emitted by the optical machine 200 can be incident on the entrance pupil area 11 of the binocular waveguide structure. The binocular waveguide structure cooperates with the optical machine 200 to form the core architecture of the augmented reality display device, outputting virtual content in front of the user, superimposing it with reality, and forming an augmented reality effect. Since the AR device adopts the binocular waveguide structure mentioned above, the binocular waveguide structure can achieve a higher degree of design freedom, achieve the purpose of diversified customization, and meet the diverse needs of customers.

[0091] The above description is only an optional embodiment of the utility model and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

[0092] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present utility model will not further describe various possible combinations.

Claims

1. A binocular waveguide structure, characterized in that: The invention comprises a waveguide plate having an entrance pupil region, a first optical path region and a second optical path region; wherein the waveguide plate is divided into a first waveguide portion and a second waveguide portion along a central axis, the first optical path region is located on the first waveguide portion, the second optical path region is located on the second waveguide portion, and the entrance pupil region is partially or completely arranged on the first waveguide portion or the second waveguide portion; the entrance pupil region, the first optical path region and the second optical path region are asymmetrically arranged relative to the central axis of the waveguide plate.

2. The binocular waveguide structure according to claim 1, characterized in that: The first optical path area includes a first exit pupil area and M first pupil expansion areas, the second optical path area includes a second exit pupil area and N second pupil expansion areas, and the M and the N are respectively greater than or equal to 0; A first exit pupil grating is provided on the first exit pupil area, and when M is greater than 0, a first pupil grating is provided on the first pupil expansion area; a second exit pupil grating is provided on the second exit pupil area, and when N is greater than 0, a second pupil grating is provided on the second pupil expansion area.

3. The binocular waveguide structure according to claim 2, characterized in that: When the first exit pupil grating and the second exit pupil grating both adopt two-dimensional gratings, and M and N are both equal to 0; The center of the entrance pupil area does not coincide with the central axis of the waveguide plate; or, the first exit pupil grating and the second exit pupil grating are different in any one of area, shape and structure; or, the first exit pupil grating and the second exit pupil grating are asymmetrically arranged relative to the central axis of the waveguide plate.

4. The binocular waveguide structure according to claim 2, characterized in that: The first exit pupil grating adopts a one-dimensional grating, the second exit pupil grating adopts a two-dimensional grating, M is greater than 0 and N is equal to 0; Alternatively, the first exit pupil grating adopts a two-dimensional grating, the second exit pupil grating adopts a one-dimensional grating, the N is greater than 0 and the M is equal to 0.

5. The binocular waveguide structure according to claim 3 or 4, characterized in that: The included angle between two grating directions of the two-dimensional grating is between 10° and 90°.

6. The binocular waveguide structure according to claim 2, characterized in that: When the first exit pupil grating and the second exit pupil grating both adopt one-dimensional gratings, and both M and N are greater than 0; The center of the entrance pupil area does not coincide with the central axis of the waveguide plate; or, any one of the area, shape and structure of the first exit pupil grating and the second exit pupil grating is different; or, the first exit pupil grating and the second exit pupil grating are asymmetrically arranged relative to the central axis of the waveguide plate; or, any one of the number, shape, area and structure of the first pupil expansion grating and the second pupil expansion grating is different; or, the first pupil expansion grating and the second pupil expansion grating are asymmetrically arranged relative to the central axis of the waveguide plate.

7. The binocular waveguide structure according to claim 2, characterized in that: The distance between the center of the first exit pupil area and the center of the second exit pupil area is between 56 mm and 70 mm.

8. The binocular waveguide structure according to claim 1, characterized in that: The material of the waveguide plate is glass or resin.

9. The binocular waveguide structure according to claim 1, characterized in that: The entrance pupil area adopts a diffraction grating.

10. An AR device, characterized in that: It comprises an optical machine and a binocular waveguide structure as described in any one of claims 1 to 9.

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