Optical waveguide components and near-eye display devices

Abstract

The present invention discloses an optical waveguide component and a near-eye display device, wherein the optical waveguide component comprises: a first waveguide plate, which is used to transmit light of a first polarization state, wherein a first coupling pupil expansion structure is arranged in the first waveguide plate, and the light of the first polarization state is coupled out from the first waveguide plate after passing through the first coupling pupil expansion structure; a second waveguide plate, which is used to transmit light of the first polarization state, wherein the second waveguide plate is stacked with the first waveguide plate, wherein a second coupling pupil expansion structure is arranged in the second waveguide plate, and the light of the first polarization state is coupled out from the second waveguide plate after passing through the second coupling pupil expansion structure; and a polarization conversion structure, wherein the polarization conversion structure is arranged between the first waveguide plate and the second waveguide plate, and the polarization conversion structure is used to convert the light of the first polarization state incident on the polarization conversion structure into the light of the second polarization state. According to the optical waveguide component of the present invention, three-dimensional display can be realized, and the production process of the optical waveguide component can be simplified.

Description

Technical Field

[0001] The present invention relates to the field of optical technology, and in particular to an optical waveguide component and a near-eye display device. Background Art

[0002] Augmented Reality (AR) technology is a technology that cleverly integrates virtual information with the real world. It can simulate computer-generated text, images, three-dimensional models, music, and videos, and apply them to the real world to supplement the real information in the real world and "enhance" the real world. This head-mounted display using augmented reality technology allows people to project virtual images into their eyes while viewing the surrounding environment, which is of great significance in the fields of military, industry, entertainment, medical care, transportation, etc.

[0003] The main technologies of transmissive head-mounted displays currently used for augmented reality include: Birdbath, prism, free-form surface and optical waveguide technology. Compared with other technologies, head-mounted displays using optical waveguide technology are smaller in size and more like a pair of glasses. Most traditional head-mounted displays based on optical waveguide technology display two-dimensional images. If three-dimensional images are to be achieved, a binocular system needs to be made and binocular imaging technology needs to be used to achieve three-dimensional display, which increases the difficulty of optical waveguide manufacturing. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention is to propose an optical waveguide component, which can realize three-dimensional display, simplify the production process of the optical waveguide component, simplify the structural design of the optical waveguide component, and reduce the volume of the optical waveguide component.

[0005] The present invention also provides a near-eye display device having the optical waveguide component.

[0006] According to the optical waveguide component of the first aspect of the present invention, the optical waveguide component comprises:

[0007] A first waveguide plate, used for transmitting light of a first polarization state, wherein a first outcoupling pupil expansion structure is arranged in the first waveguide plate, and the light of the first polarization state is coupled out from the first waveguide plate after passing through the first outcoupling pupil expansion structure, so as to be emitted to a light output side of the optical waveguide component;

[0008] a second waveguide plate, for transmitting light of a first polarization state, the second waveguide plate being stacked with the first waveguide plate, a second out-coupling pupil expansion structure being arranged in the second waveguide plate, and the light of the first polarization state being coupled out from the second waveguide plate after passing through the second out-coupling pupil expansion structure to be emitted to a light-emitting side of the optical waveguide assembly;

[0009] A polarization conversion structure, wherein the polarization conversion structure is arranged between the first waveguide plate and the second waveguide plate, and the polarization conversion structure is used to convert light of a first polarization state incident on the polarization conversion structure into light of a second polarization state, wherein the vibration directions of the light of the first polarization state and the light of the second polarization state are perpendicular.

[0010] In some embodiments, a first turning pupil expansion structure is further provided in the first waveguide plate, and the light of the first polarization state in the first waveguide plate is expanded by the first turning pupil expansion structure and then emitted to the first out-coupling pupil expansion structure;

[0011] A second turning pupil expansion structure is also provided in the second waveguide plate, and the light of the first polarization state in the second waveguide plate is expanded by the second turning pupil expansion structure and then emitted to the second coupling-out pupil expansion structure.

[0012] In some optional embodiments, the first turning pupil expansion structure includes a plurality of first beam splitters, and the plurality of first beam splitters are arranged in parallel at equal intervals;

[0013] The second turning pupil expansion structure includes a plurality of second beam splitters, which are arranged in parallel at equal intervals, wherein the second beam splitters are parallel to or have an angle with the first beam splitter.

[0014] In some optional embodiments, the optical waveguide component further includes a coupling element, and two coupling elements are provided, and the two coupling elements are respectively provided on the first waveguide plate and the second waveguide plate.

[0015] In some optional embodiments, the coupling element is a prism or a reflector.

[0016] In some embodiments, optical glue is further included, and the first waveguide plate, the second waveguide plate and the polarization conversion structure are bonded together by the optical glue.

[0017] In some optional embodiments, the refractive index of the optical glue is n G , the refractive index of the first waveguide plate and the second waveguide plate is n w , the transmission angle of the light of the first polarization state in the first waveguide plate and the second waveguide plate is α, the angle formed by the first out-coupling pupil expansion structure and the first waveguide plate is θ, and the angle formed by the second out-coupling pupil expansion structure and the second waveguide plate is also θ, wherein the refractive index n of the optical glue is G satisfy:

[0018] In some embodiments, the polarization conversion structure includes a half wave plate, and the half wave plate is used to convert light in a first polarization state into light in a second polarization state.

[0019] According to the optical waveguide component of the present invention, by setting a polarization conversion structure between the first waveguide plate and the second waveguide plate, the first waveguide plate and the second waveguide plate are both used to transmit light in the first polarization state, and the polarization conversion structure converts the light in the first polarization state coupled out from the second waveguide plate into light in the second polarization state, so that the light-emitting side of the optical waveguide component includes an image in the first polarization state and an image in the second polarization state. When polarized lenses with different polarization directions are respectively set in front of the left and right eyes of a person, so that the left eye receives the image in the first polarization state and the right eye receives the image in the second polarization state, the optical waveguide component realizes three-dimensional display. In addition, the first waveguide plate and the second waveguide plate are stacked, and there is no need to perform binocular combination and other processes, which simplifies the production process of the optical waveguide component, simplifies the structural design of the optical waveguide component, and reduces the volume of the optical waveguide component.

[0020] According to the second aspect of the present invention, the near-eye display device comprises a first projection device, a second projection device and an optical waveguide assembly according to the first aspect of the present invention, wherein the first projection device is used to project a first polarized light into a first waveguide plate, and the second projection device is used to project a first polarized light into a second waveguide plate.

[0021] In some embodiments, the optical waveguide component includes two coupling elements, the two coupling elements are respectively arranged on the first waveguide plate and the second waveguide plate, and the two coupling elements are arranged at opposite ends of the optical waveguide component, and the first projection device and the second projection device are arranged on opposite sides of the optical waveguide component and are arranged corresponding to the two coupling elements.

[0022] According to the near-eye display device of the present invention, the optical waveguide component of the first aspect is provided, thereby improving the overall performance of the near-eye display device.

[0023] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of an optical waveguide assembly according to one embodiment of the present invention;

[0025] Figure 2 is a schematic diagram of a first waveguide according to an embodiment of the present invention;

[0026] Figure 3 is a schematic diagram of a second waveguide according to an embodiment of the present invention;

[0027] Figure 4 is a side schematic diagram of an optical waveguide assembly according to one embodiment of the present invention;

[0028] Figure 5 The present invention Figure 4 Enlarged view of point A in the middle.

[0029] Reference numerals:

[0030] 100: optical waveguide component; 10: first waveguide plate; 101: first sub-waveguide; 102: second sub-waveguide; 11: first out-coupling pupil expansion structure; 12: first turning pupil expansion structure; s10: waveguide surface; 20: second waveguide plate; 201: third sub-waveguide; 202: fourth sub-waveguide; 21: second out-coupling pupil expansion structure; 22: second turning pupil expansion structure; 30: polarization conversion structure; 40: coupling element; 50: optical adhesive;

[0031] 210: first polarizer; 220: second polarizer; a: left eye; b: right eye. DETAILED DESCRIPTION

[0032] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0033] The disclosure below provides many different embodiments or examples to implement different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or letters in different examples. This repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides various specific processes and examples of materials, but those of ordinary skill in the art can be aware of the applicability of other processes and / or the use of other materials.

[0034] Reference below Figure 1-Figure 5 The optical waveguide assembly 100 according to an embodiment of the present invention is described. The optical waveguide assembly 100 is a medium device that guides light waves to propagate therein. The light projected by the projection device can be guided to the front of the eyes, and a virtual image is superimposed on the real image in front of the human eye, thereby realizing the function of augmented reality. The optical waveguide assembly 100 includes a first waveguide sheet 10, a polarization conversion structure 30, and a second waveguide sheet 20 that are stacked in sequence, wherein the first waveguide sheet 10 and the second waveguide sheet 20 are used to transmit light, and the polarization conversion structure 30 is used to convert the polarization state of light.

[0035] like Figure 1-Figure 2As shown, further, the first waveguide plate 10 can be used to transmit light of a first polarization state, and a first out-coupling pupil expansion structure 11 is provided in the first waveguide plate 10. After the light of the first polarization state passes through the first out-coupling pupil expansion structure 11, it is coupled out from the first waveguide plate 10 to emit to the light output side of the optical waveguide component 100. It can be understood that the light can be transmitted in the first waveguide plate 10 by total reflection, wherein the light can include light of the first polarization state and light of the second polarization state. When the light of the first polarization state is transmitted to the first out-coupling pupil expansion structure 11, the first out-coupling pupil expansion structure 11 expands the light of the first polarization state in a first direction (such as the Y direction in FIG. 1 ), and couples the light of the first polarization state out of the first waveguide plate 10.

[0036] Please refer to Figure 3 , the second waveguide plate 20 can also be used to transmit light of the first polarization state. The second waveguide plate 20 is stacked with the first waveguide plate 10. A second out-coupling pupil expansion structure 21 is arranged in the second waveguide plate 20. After the light of the first polarization state passes through the second out-coupling pupil expansion structure 21, it is coupled out from the second waveguide plate 20 to emit to the light output side of the optical waveguide component 100. It can be understood that the structure of the second waveguide plate 20 is basically the same as that of the first waveguide plate 10, and the light can also be transmitted in the second waveguide plate 20 by total reflection, wherein the light can include light of the first polarization state and light of the second polarization state. When the light of the first polarization state is transmitted to the second out-coupling pupil expansion structure 21, the second out-coupling pupil expansion structure 21 converts the light of the first polarization state into a first direction (such as Figure 1 The light is expanded in the Y direction (in the middle), and the light of the first polarization state is coupled out from the second waveguide plate 20.

[0037] It can be understood that the first waveguide sheet 10 and the second waveguide sheet 20 can be made of transparent glass material or transparent resin material. Glass material has better optical properties, for example, better transmission performance, ensuring the amount of light transmission; resin material is easy to process, and the first waveguide sheet 10 and the second waveguide sheet 20 can be obtained by processes such as thermoplastic molding. The first out-coupling pupil expansion structure 11 and the second out-coupling pupil expansion structure 21 can be arrayed spectroscopic films.

[0038] It should be noted that in order to ensure that the light can be fully reflected and transmitted in the first waveguide plate 10 and the second waveguide plate 20, there may be an air gap between the first waveguide plate 10 and the polarization conversion structure 30, and there may also be an air gap between the second waveguide plate 20 and the polarization conversion structure 30. Since the refractive index of air is lower than the refractive index of the first waveguide plate 10 and the second waveguide plate 20, the light can be fully reflected and transmitted in the first waveguide plate 10 and the second waveguide plate 20.

[0039] Please refer to Figure 4Furthermore, a polarization conversion structure 30 is disposed between the first waveguide plate 10 and the second waveguide plate 20, and the polarization conversion structure 30 is used to convert light of a first polarization state incident on the polarization conversion structure 30 into light of a second polarization state, wherein vibration directions of the light of the first polarization state and the light of the second polarization state are perpendicular.

[0040] The basic principle of 3D display technology is to simulate the way human eyes view the real world, that is, when observing the same object with two eyes, the distance between the two eyes creates a visual difference, so that the left and right eyes see slightly different images, and the brain synthesizes these slightly different images into a three-dimensional image. Polarized 3D display uses the principle that light has a vibration direction to divide the image into a first polarization state image and a second polarization state image with polarization directions perpendicular to each other. By using polarized lenses with different polarization directions, the left eye receives the image of the first polarization state and the right eye receives the image of the second polarization state, so that the left and right eyes of a person can receive two sets of images, and the brain synthesizes the three-dimensional image.

[0041] Please refer to Figure 5 In this embodiment, the first waveguide plate 10 transmits the light of the first polarization state by total reflection. After passing through the first out-coupling pupil expansion structure 11, the light of the first polarization state is coupled out from the first waveguide plate 10 and emitted to the light-emitting side of the optical waveguide component 100 to form an image of the first polarization state. The second waveguide plate 20 transmits the light of the first polarization state by total reflection. After passing through the second out-coupling pupil expansion structure 21, the light of the first polarization state is coupled out from the second waveguide plate 20 and emitted to the light-emitting side of the optical waveguide component 100. Due to the polarization turning structure It is arranged between the first waveguide sheet 10 and the second waveguide sheet 20. When the light-emitting side of the optical waveguide assembly 100 is the side of the first waveguide sheet 10 away from the second waveguide sheet 20, the light of the first polarization state coupled out from the second waveguide sheet 20 will pass through the polarization conversion structure 30 when it is emitted to the light-emitting side. Therefore, the light of the first polarization state coupled out from the second waveguide sheet 20 is converted into light of the second polarization state by the polarization conversion structure 30 and emitted to the light-emitting side of the optical waveguide assembly 100 to form an image of the second polarization state. By respectively arranging polarized lenses with different polarization directions in front of the left eye a and the right eye b of a person, the left eye a receives the image of the first polarization state and the right eye b receives the image of the second polarization state, so that the left and right eyes b of a person can receive two sets of images. When the two sets of images are only slightly different, a three-dimensional stereoscopic image can be synthesized by the brain, so that the optical waveguide assembly 100 can realize three-dimensional display.

[0042] The inventors found in actual research that most of the traditional systems based on optical waveguide technology display 2D images. If 3D images are to be achieved, it is necessary to make a binocular system and use binocular imaging technology to achieve 3D display, which increases the process difficulty of optical waveguide manufacturing and is not conducive to the miniaturization of head-mounted displays.

[0043] In view of this, according to the optical waveguide component 100 implemented in the present invention, by setting a polarization conversion structure 30 between the first waveguide sheet 10 and the second waveguide sheet 20, the first waveguide sheet 10 and the second waveguide sheet 20 are both used to transmit light of the first polarization state, and the polarization conversion structure 30 converts the light of the first polarization state coupled out from the second waveguide sheet 20 into light of the second polarization state, so that the light-emitting side of the optical waveguide component 100 includes an image of the first polarization state and an image of the second polarization state. When polarized lenses with different polarization directions are respectively set in front of the left eye a and the right eye b of a person, so that the left eye a receives the image of the first polarization state and the right eye b receives the image of the second polarization state, the optical waveguide component 100 realizes three-dimensional display. In addition, the first waveguide sheet 10 and the second waveguide sheet 20 are stacked, and there is no need to perform binocular combination and other processes, which simplifies the production process of the optical waveguide component 100, simplifies the structural design of the optical waveguide component 100, and reduces the volume of the optical waveguide component 100.

[0044] It should be noted that, in the present embodiment, the first out-coupling pupil expansion structure 11 and the second out-coupling pupil expansion structure 21 may be arrayed spectroscopic films. Since the first waveguide plate 10 and the second waveguide plate 20 are both used to transmit light of the first polarization state, the arrayed spectroscopic film forming the first out-coupling pupil expansion structure 11 and the arrayed spectroscopic film forming the second out-coupling pupil expansion structure 21 may be the same, and both are used to couple out light of the first polarization state, so that the structures of the first waveguide plate 10 and the second waveguide plate 20 may be basically the same, thereby further simplifying the production process of the optical waveguide component 100.

[0045] Please refer to Figure 1-Figure 5 As shown, in some embodiments, a first turning pupil dilation structure 12 is further provided in the first waveguide 10, and the light of the first polarization state in the first waveguide 10 is expanded by the first turning pupil dilation structure 12 and then emitted to the first coupling pupil dilation structure 11; it should be noted that the first turning pupil dilation structure 12 can expand the light of the first polarization state in the second direction (such as the X direction in Figure 1), and emit the expanded light of the first polarization state to the first coupling pupil dilation structure 11, so that the light of the first polarization state emitted from the first waveguide 10 can be dilated in two directions.

[0046] It should be noted that there is an angle between the first direction and the second direction. Specifically, the angle between the first direction and the second direction can be 30°, 45°, 60°, 90°, etc. For example, in this embodiment, the angle between the first direction and the second direction is 90°.

[0047] Please continue to refer to Figure 1-Figure 5As shown, a second turning pupil dilation structure 22 is further provided in the second waveguide 20, and the light of the first polarization state in the second waveguide 20 is expanded by the second turning pupil dilation structure 22 and then emitted to the second out-coupling pupil dilation structure 21. The second turning pupil dilation structure 22 can expand the light of the first polarization state in the second waveguide 20 in the second direction (such as the X direction in FIG. 1 ), and emit the expanded light of the first polarization state to the second out-coupling pupil dilation structure 21, so that the light of the first polarization state emitted from the second waveguide 20 can also be expanded in two directions.

[0048] Therefore, by providing the first turning pupil expansion structure 12 and the second turning pupil expansion structure 22, the pupil of the optical waveguide component 100 can be expanded in both the first direction and the second direction, further enhancing the user experience.

[0049] Please continue to refer to Figure 1-Figure 5 As shown, in some optional embodiments, the first turning pupil expansion structure 12 includes a plurality of first beam splitters, which are arranged in parallel at equal intervals; the second turning pupil expansion structure 22 includes a plurality of second beam splitters, which are arranged in parallel at equal intervals, wherein the second beam splitters are parallel to or have an angle with the first beam splitters.

[0050] It can be understood that the spacing between the plurality of first beam splitters and the spacing between the plurality of second beam splitters can be the same, when the first beam splitters are parallel to the second beam splitters, that is, the first turning pupil expansion structure 12 is substantially the same as the second turning pupil expansion structure 22, and the structures of the first waveguide sheet 10 and the second waveguide sheet 20 are substantially the same. Therefore, the production process of the optical waveguide assembly 100 can be further simplified.

[0051] In other embodiments of the present invention, the second beam splitter and the first beam splitter may also have an angle, that is, the first waveguide plate 10 and the second waveguide plate 20 have different structures and can be specifically configured according to requirements, which is not limited in the embodiments of the present invention.

[0052] Please continue to refer to Figure 1-Figure 5 As shown, it should be noted that, in some specific embodiments, the first waveguide sheet 10 may include a first sub-waveguide 101 and a second sub-waveguide 102, the second waveguide sheet 20 may include a third sub-waveguide 201 and a fourth sub-waveguide 202, the first turning pupil expansion structure 12 may be disposed in the first sub-waveguide 101, the first coupling pupil expansion structure 11 may be disposed in the second sub-waveguide 102, and the first sub-waveguide 101 and the second sub-waveguide 102 are bonded to form the first waveguide sheet 10. Similarly, the second turning pupil expansion structure 22 may be disposed in the third sub-waveguide 201, the second coupling pupil expansion structure 21 may be disposed in the fourth sub-waveguide 202, and the third sub-waveguide 201 and the fourth sub-waveguide 202 are bonded to form the second waveguide sheet 20.

[0053] When the first beam splitter and the second beam splitter have an included angle, the first sub-waveguide 101 may be rotated 180° to form the third sub-waveguide 201, and then the third sub-waveguide 201 and the fourth sub-waveguide 202 are bonded to form the second waveguide sheet 20. In addition, since the third sub-waveguide 201 is obtained by rotating the first sub-waveguide 101 by 180°, the first projection device and the second projection device for projecting light may be disposed on opposite sides of the optical waveguide component 100, thereby further simplifying the production process of the optical waveguide component 100 and facilitating the optimization of the structural design of the optical waveguide component 100.

[0054] Please continue to refer to Figure 1-Figure 5 As shown, in some optional embodiments, the optical waveguide assembly 100 further includes a coupling element 40, and two coupling elements 40 are provided, and the two coupling elements 40 are respectively provided on the first waveguide plate 10 and the second waveguide plate 20. Therefore, the coupling element 40 can be used to couple the light of the first polarization state emitted by the first projection device into the first waveguide plate 10, and the light of the second polarization state projected by the second projection device into the second waveguide plate 20, so as to realize augmented reality display.

[0055] Specifically, when the first sub-waveguide 101 is rotated 180° to form the third sub-waveguide 201, the coupling elements 40 of the first waveguide plate 10 and the second waveguide plate 20 can be arranged on opposite sides of the optical waveguide component 100, thereby further simplifying the production process of the optical waveguide component 100 and facilitating the optimization of the structural design of the optical waveguide component 100.

[0056] In some optional embodiments, the coupling element 40 is a prism or a reflector. It should be noted that, taking the first waveguide plate 10 as an example, when the coupling element 40 is a prism, the angle between the coupling surface and the waveguide surface s10 can be 60°-80°, specifically, for example, the angle between the coupling surface and the waveguide surface s10 is 70°; when the coupling element 40 is a reflector, the reflector can be embedded in the first waveguide plate 10, and the angle between the reflection surface and the waveguide surface s10 can be 30°-40°, specifically, for example, the angle between the reflection surface and the waveguide surface s10 is 35°.

[0057] Therefore, by configuring the coupling element 40 as a prism or a reflector, the structure of the optical waveguide component 100 is simple, which further simplifies the production process of the optical waveguide component 100 and helps optimize the structural design of the optical waveguide component 100 .

[0058] Please continue to refer to Figure 1-Figure 5As shown, in some embodiments, an optical glue 50 is further included, and the first waveguide sheet 10, the second waveguide sheet 20 and the polarization conversion structure 30 are bonded together by the optical glue 50. Thus, the optical waveguide assembly 100 is bonded together by the optical glue 50, and the structure is stable and reliable, which is conducive to improving the mass production of the optical waveguide assembly 100.

[0059] It should be noted that in order to ensure that the light can be transmitted by total reflection in the first waveguide plate 10 and the second waveguide plate 20, the refractive index of the optical glue 50 needs to be lower than the refractive index of the first waveguide plate 10 and the second waveguide plate 20, so that the light can meet the total reflection condition when it is transmitted in the first waveguide plate 10 and the second waveguide plate 20.

[0060] Please continue to refer to Figure 1-Figure 5 As shown, in some optional embodiments, the refractive index of the optical glue 50 is n G The refractive index of the first waveguide plate 10 and the second waveguide plate 20 is n w , the transmission angle of the light of the first polarization state in the first waveguide plate 10 and the second waveguide plate 20 is α, the angle formed by the first out-coupling pupil expansion structure 11 and the first waveguide plate 10 is θ, and the angle formed by the second out-coupling pupil expansion structure 21 and the second waveguide plate 20 is also θ, wherein the refractive index n of the optical glue 50 is G satisfy:

[0061]

[0062] Therefore, by reasonably setting the refractive index of the optical adhesive 50 , while ensuring that the light in the first waveguide plate 10 and the second waveguide plate 20 can be fully reflected and transmitted, it can be ensured that the optical waveguide assembly 100 has a good optical effect.

[0063] Please continue to refer to Figure 1-Figure 5 As shown, in some embodiments, the polarization conversion structure 30 includes a half wave plate, and the half wave plate is used to convert the first polarized light into the second polarized light. Therefore, the half wave plate has a simple structure, and the half wave plate is used to convert the light of the first polarization state into the light of the second polarization state, which further simplifies the production process of the optical waveguide component 100 and is conducive to optimizing the structural design of the optical waveguide component 100.

[0064] Specifically, in an embodiment of the present invention, the light of the first polarization state may be s-polarized light, and the light of the second polarization state may be p-polarized light. The s-polarized light projected by the first projection device enters the first waveguide plate 10 after passing through the coupling element 40, and is transmitted by total reflection in the first waveguide plate 10. When transmitted to the first turning pupil expansion structure 12, the first turning pupil expansion structure 12 expands the s-polarized light in the second direction, and transmits the light to the first coupling pupil expansion structure 11. The first coupling pupil expansion structure 11 expands the s-polarized light in the first direction, couples the s-polarized light out of the first waveguide plate 10, and projects it toward the light output side of the optical waveguide component 100 to form an image of the first polarization state. The left eye a of a person may be provided with a first polarizer 210 that only allows s-polarized light to pass through, so that the left eye a can receive the image of the first polarization state.

[0065] Similarly, the s-polarized light projected by the second projection device enters the second waveguide plate 20 after passing through the coupling element 40, and is transmitted by total reflection in the second waveguide plate 20. When transmitted to the second turning pupil expansion structure 22, the second turning pupil expansion structure 22 expands the s-polarized light in the second direction, and transmits the light to the second coupling pupil expansion structure 21, and directs it toward the light exiting side of the optical waveguide component 100. The second coupling pupil expansion structure expands the s-polarized light in the first direction, and couples the s-polarized light out of the second waveguide plate 20 to direct it toward the light exiting side of the optical waveguide component 100. The s-polarized light coupled out from the second waveguide plate 20 is converted into p-polarized light after passing through a half wave plate, and forms an image in the second polarization state. The right eye b of a person may be provided with a second polarizer 220 that only allows p-polarized light to pass through, so that the right eye b can receive the image in the second polarization state.

[0066] According to the basic principle of 3D display technology, when observing the same object with two eyes, the distance between the two eyes produces visual difference, so that the images seen by the left and right eyes are slightly different, and the brain combines these slightly different images into a 3D image. When the image in the first polarization state and the image in the second polarization state are slightly different, the brain combines these slightly different images into a 3D image, thereby realizing 3D display.

[0067] According to the second aspect of the present invention, a near-eye display device comprises a first projection device, a second projection device and an optical waveguide assembly 100 according to the first aspect of the present invention, wherein the first projection device is used to project a first polarized light into a first waveguide sheet 10, and the second projection device is used to project a first polarized light into a second waveguide sheet 20. The first projection device is disposed correspondingly to the first waveguide sheet 10, and the second projection device is disposed correspondingly to the second waveguide sheet 20.

[0068] Therefore, according to the near-eye display device of the present invention, by setting the optical waveguide component 100 of the first aspect mentioned above, the near-eye display device can realize three-dimensional display, and the first waveguide sheet 10 and the second waveguide sheet 20 are stacked, and there is no need to perform binocular imaging and other processes, which simplifies the production process of the optical waveguide component 100, simplifies the structural design of the optical waveguide component 100, and reduces the volume of the optical waveguide component 100, thereby improving the overall performance of the near-eye display device.

[0069] In some embodiments, the optical waveguide component 100 includes two coupling elements 40, the two coupling elements 40 are respectively disposed on the first waveguide plate 10 and the second waveguide plate 20, and the two coupling elements 40 are disposed at opposite ends of the optical waveguide component 100, and the first projection device and the second projection device are disposed on opposite sides of the optical waveguide component 100, and are disposed corresponding to the two coupling elements 40. Therefore, the first projection device and the second projection device can be disposed on both sides of the optical waveguide component 100, which is conducive to optimizing the structural design of the optical waveguide component 100 and further improving the overall performance of the near-eye display device.

[0070] Other structures and operations of the optical waveguide assembly 100 and the near-eye display device according to the embodiment of the present invention are well known to those skilled in the art and will not be described in detail here.

[0071] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0072] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0073] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0074] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0075] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0076] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. An optical waveguide component, which is applied to a near-eye display device to achieve three-dimensional display, characterized in that: The optical waveguide assembly comprises: A first waveguide plate, used for transmitting light of a first polarization state, wherein a first outcoupling pupil expansion structure is arranged in the first waveguide plate, and the light of the first polarization state is coupled out from the first waveguide plate after passing through the first outcoupling pupil expansion structure, so as to be emitted to a light output side of the optical waveguide component; a second waveguide plate, for transmitting light of a first polarization state, the second waveguide plate being stacked with the first waveguide plate, a second out-coupling pupil expansion structure being arranged in the second waveguide plate, and the light of the first polarization state being coupled out from the second waveguide plate after passing through the second out-coupling pupil expansion structure to be emitted to a light-emitting side of the optical waveguide assembly; A polarization conversion structure, wherein the polarization conversion structure is arranged between the first waveguide plate and the second waveguide plate, and the polarization conversion structure is used to convert the light of the first polarization state incident on the polarization conversion structure into the light of the second polarization state, so that the light output side of the optical waveguide component includes an image of the first polarization state formed by the light of the first polarization state and an image of the second polarization state formed by the light of the second polarization state, wherein the vibration directions of the light of the first polarization state and the light of the second polarization state are perpendicular.

2. The optical waveguide assembly according to claim 1, characterized in that A first turning pupil expansion structure is also provided in the first waveguide plate, and the light of the first polarization state in the first waveguide plate is expanded by the first turning pupil expansion structure and then emitted to the first coupling-out pupil expansion structure; A second turning pupil expansion structure is also provided in the second waveguide plate, and the light of the first polarization state in the second waveguide plate is expanded by the second turning pupil expansion structure and then emitted to the second coupling-out pupil expansion structure.

3. The optical waveguide assembly according to claim 2, characterized in that The first turning pupil expansion structure includes a plurality of first beam splitters, and the plurality of first beam splitters are arranged in parallel with equal intervals; The second turning pupil expansion structure includes a plurality of second beam splitters, which are arranged in parallel at equal intervals, wherein the second beam splitters are parallel to or have an angle with the first beam splitter.

4. The optical waveguide assembly according to claim 3, characterized in that The optical waveguide component further includes a coupling element. Two coupling elements are provided. The two coupling elements are respectively provided on the first waveguide plate and the second waveguide plate.

5. The optical waveguide assembly according to claim 4, characterized in that The coupling-in element is a prism or a reflector.

6. The optical waveguide assembly according to claim 1, wherein: It also includes optical glue, and the first waveguide plate, the second waveguide plate and the polarization conversion structure are bonded together by the optical glue.

7. The optical waveguide assembly according to claim 6, characterized in that The refractive index of the optical glue is n G , the refractive index of the first waveguide plate and the second waveguide plate is n w , the transmission angle of the light of the first polarization state in the first waveguide plate and the second waveguide plate is α, the angle formed by the first out-coupling pupil expansion structure and the first waveguide plate is θ, and the angle formed by the second out-coupling pupil expansion structure and the second waveguide plate is also θ, wherein the refractive index n of the optical glue is G satisfy: .

8. The optical waveguide assembly according to claim 1, wherein: The polarization conversion structure includes a half-wave plate, and the half-wave plate is used to convert light in a first polarization state into light in a second polarization state.

9. A near-eye display device, characterized in that: It comprises a first projection device, a second projection device and an optical waveguide assembly as described in any one of claims 1 to 8, wherein the first projection device is used to project a first polarized light into a first waveguide plate, and the second projection device is used to project a first polarized light into a second waveguide plate.

10. The near-eye display device according to claim 9, characterized in that: The optical waveguide component includes two coupling elements, which are respectively arranged on the first waveguide plate and the second waveguide plate, and the two coupling elements are arranged at opposite ends of the optical waveguide component. The first projection device and the second projection device are arranged on opposite sides of the optical waveguide component and are arranged corresponding to the two coupling elements.

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