Optical waveguide assembly and near-eye display device

Abstract

The application discloses an optical waveguide assembly and a near-eye display device. The optical waveguide assembly comprises a first waveguide sheet, a first pupil expanding structure arranged in the first waveguide sheet, the first pupil expanding structure expanding light in the first waveguide sheet along a first direction, a second waveguide sheet, the second waveguide sheet being arranged in a stack with the first waveguide sheet, a second pupil expanding structure arranged in the second waveguide sheet, the second pupil expanding structure expanding light in the second waveguide sheet along a second direction, the first direction and the second direction having an included angle, and a light path turning element arranged at one end of the first waveguide sheet and the second waveguide sheet, the light path turning element being used for receiving expanded light emitted from the first pupil expanding structure and shooting the expanded light to the second pupil expanding structure, the second pupil expanding structure coupling the expanded light out of the second waveguide sheet after receiving the expanded light to enter a human eye. According to the optical waveguide assembly, user experience can be improved, and the structural design of the product can be optimized.

Description

Technical Field

[0001] This invention relates to the field of optical display technology, and in particular to an optical waveguide assembly and a near-eye display device. Background Technology

[0002] Near-eye display devices for augmented reality allow people to view virtual images projected onto the real world they perceive while looking at their surroundings. These virtual images are superimposed on the real world perceived by the user, creating a more realistic experience and a stronger sense of immersion. The main technologies include birdbath, prism, freeform surfaces, and optical waveguide technology. Compared to other technologies, near-eye display devices using optical waveguide technology have the advantages of a larger field of view and a smaller size.

[0003] Two-dimensional array waveguides can expand their pupils in both directions, achieving better imaging results with a more compact volume. However, existing two-dimensional array waveguides typically place the primary and secondary pupil expansion structures on the same waveguide substrate. The primary pupil expansion structure is the upper structure, and the secondary pupil expansion structure is the lower structure. The upper structure is responsible for lateral pupil expansion, and the lower structure is responsible for vertical pupil expansion. After the upper structure expands the pupil, it directs the light to the lower structure, which then expands the pupil again and couples the light out from the waveguide substrate to the human eye. Therefore, the human eye can only view the virtual image from the lower area of ​​the lens, affecting product design and resulting in a poor user experience. Summary of the Invention

[0004] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the present invention provides an optical waveguide assembly that can improve the utilization rate of the space area of ​​the front view of the first and second waveguide sheets, enhance the user experience, and optimize the structural design of the product.

[0005] The present invention also proposes a near-eye display device having the above-mentioned optical waveguide components.

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

[0007] A first waveguide sheet, wherein a first pupil-expanding structure is provided within the first waveguide sheet, and the first pupil-expanding structure expands the light within the first waveguide sheet along a first direction;

[0008] The second waveguide sheet is stacked with the first waveguide sheet. A second pupil structure is provided inside the second waveguide sheet. The second pupil structure expands the light inside the second waveguide sheet along a second direction. There is an angle between the first direction and the second direction.

[0009] An optical path deflection element is disposed at one end of the first waveguide and the second waveguide. The optical path deflection element is used to receive the extended light emitted from the first pupil dilator structure and direct the extended light to the second pupil dilator structure. After receiving the extended light, the second pupil dilator structure couples the extended light out from the second waveguide to enter the human eye.

[0010] In some embodiments, the first pupil dilator and / or the second pupil dilator is an array beam splitter.

[0011] In some embodiments, the optical path deflection element includes a plurality of mirrors, and the extended light rays emitted from the first pupil dilator structure are directed toward the second pupil dilator structure after passing through the plurality of mirrors.

[0012] In some embodiments, the optical path deflection element includes a deflection prism, on which a first reflecting surface and a second reflecting surface are provided. The extended light rays emitted from the first waveguide sheet are reflected by the first reflecting surface and then directed to the second reflecting surface. The second reflecting surface reflects the light rays and directs them to the second pupil dilator structure.

[0013] In some optional embodiments, the turning prism is an isosceles right-angled triangular prism, wherein the faces corresponding to the two right-angled sides of the isosceles right-angled triangular prism respectively form a first reflecting surface and a second reflecting surface.

[0014] In some alternative embodiments, the deflection prism includes a first sub-prism and a second sub-prism, which are spliced ​​together to form the deflection prism.

[0015] In some optional embodiments, the optical path deflection element further includes:

[0016] The first polarizing beam splitter is provided on both the side of the first sub-prism facing the first waveguide and the side of the second sub-prism facing the second waveguide. The first polarizing beam splitter is used to transmit light of the first polarization state and reflect light of the second polarization state, wherein the vibration direction of the light of the first polarization state is perpendicular to that of the light of the second polarization state.

[0017] The second polarizing beam splitter is disposed between the first sub-prism and the second sub-prism. The second polarizing beam splitter is used to transmit light of the second polarization state and reflect light of the first polarization state.

[0018] A quarter-wave plate is provided on both the first and second reflecting surfaces near the deflecting prism, and the quarter-wave plate is used to change the vibration direction of light.

[0019] In some embodiments, the first waveguide sheet, the second waveguide sheet, and the optical path deflection element are bonded together by optical adhesive.

[0020] In some optional embodiments, a coupling structure is also included, which is disposed on the first waveguide sheet for coupling light into the first waveguide sheet.

[0021] According to the optical waveguide assembly of the present invention, by stacking a first waveguide sheet and a second waveguide sheet, and providing an optical path deflection element at one end of the first and second waveguide sheets, a first pupil expansion structure can be provided in the first waveguide sheet, and a second pupil expansion structure can be provided in the second waveguide sheet. The optical path deflection element can transmit the expanded light rays after the first pupil expansion structure to the second pupil expansion structure, so that the expanded light rays are expanded again to form two-dimensional expanded light rays. Furthermore, since the first and second waveguide sheets are stacked, the utilization rate of the space area of ​​the front view surface of the first and second waveguide sheets is improved, the user experience is enhanced, and the structural design of the product is optimized.

[0022] A near-eye display device according to a second aspect of the present invention includes a projection device and an optical waveguide assembly according to a first aspect of the present invention.

[0023] According to the near-eye display device of the present invention, by providing the optical waveguide component of the first aspect described above, the overall performance of the near-eye display device is improved.

[0024] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0025] Figure 1 This is a three-dimensional schematic diagram of an optical waveguide assembly according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of an optical waveguide assembly according to an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of an optical waveguide assembly according to another embodiment of the present invention;

[0028] Figure 4 This is a three-dimensional schematic diagram of an optical waveguide assembly according to another embodiment of the present invention;

[0029] Figure 5 This is a schematic diagram of an optical waveguide assembly according to yet another embodiment of the present invention;

[0030] Figure 6 This is a schematic diagram of an optical waveguide assembly according to another embodiment of the present invention;

[0031] Figure 7 This is a schematic diagram of an optical waveguide assembly according to another embodiment of the present invention.

[0032] Figure label:

[0033] 100: Optical waveguide assembly; 10: First waveguide sheet; 11: First pupil dilator structure; 20: Second waveguide sheet; 21: Second pupil dilator structure; 30: Optical path deflection element; 31: Reflector; 32: Deflection prism; 321: First reflecting surface; 322: Second reflecting surface; 323: First sub-prism; 324: Second sub-prism; 35: First polarizing beam splitter; 36: Second polarizing beam splitter; 37: Quarter-wave plate; 40: Air gap; 50: Optical adhesive Detailed Implementation

[0034] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0035] The following disclosure provides numerous different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. Additionally, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the applicability of other processes and / or the use of other materials.

[0036] The following is for reference. Figures 1-7 The optical waveguide assembly 100 according to an embodiment of the present invention is described. The optical waveguide assembly 100 is a medium device for guiding light waves to propagate therein. It can guide the light projected by a projection device to the front of the eyes, superimposing a virtual image on top of a real image in front of the eyes, thereby realizing the function of augmented reality. The optical waveguide assembly 100 includes a first waveguide sheet 10, a second waveguide sheet 20, and an optical path deflection element 30, wherein the first waveguide sheet 10 and the second waveguide sheet 20 are stacked, and the optical path deflection element 30 is disposed at one end of the first waveguide sheet 10 and the second waveguide sheet 20.

[0037] It should be noted that the first waveguide 10 and the second waveguide 20 can be made of transparent glass or transparent resin. Glass has better optical properties, such as better transmission performance, which ensures the amount of light transmitted. Resin is easy to process, and the first waveguide 10 and the second waveguide 20 can be obtained through processes such as thermoplastic molding.

[0038] Please refer to Figure 1 As shown, further, a first pupil dilator structure 11 is provided within the first waveguide sheet 10, and the first pupil dilator structure 11 is along a first direction (such as...). Figure 1 In the X direction, the light rays within the first waveguide 10 are extended; it can be understood that when the light rays within the first waveguide 10 are transmitted to the first pupil structure 11, the first pupil structure 11 can extend the light rays within the first waveguide 10 in the first direction.

[0039] Please continue to refer to Figure 1 Furthermore, the second waveguide 20 is stacked with the first waveguide 10, and a second pupil dilator 21 is provided within the second waveguide 20. The second pupil dilator 21 is arranged along a second direction (e.g., Figure 1 The first direction (Y direction) expands the light rays within the second waveguide 20, and there is an angle between the first direction and the second direction. It can be understood that when the light rays within the second waveguide 20 are transmitted to the second pupil structure 21, the second pupil structure 21 can expand the light rays within the second waveguide 20 in the second direction.

[0040] It should be noted that, in order to ensure that light can be transmitted by total internal reflection within the first waveguide 10 and the second waveguide 20, when the second waveguide 20 and the first waveguide 10 are stacked, the first waveguide 10 and the second waveguide 20 need to be spaced a certain distance apart. Specifically, for example, there can be an air gap 40 between the second waveguide 20 and the first waveguide 10. Since the refractive index of air is lower than that of the first waveguide 10 and the second waveguide 20, light can be transmitted by total internal reflection within the first waveguide 10 and the second waveguide 20.

[0041] Please continue to refer to Figure 1 Furthermore, the optical path deflection element 30 is disposed at one end of the first waveguide 10 and the second waveguide 20. The optical path deflection element 30 is used to receive the extended light emitted from the first pupil dilator 11 and direct the extended light to the second pupil dilator 21. After receiving the extended light, the second pupil dilator 21 couples the extended light out from the second waveguide 20 so that it can enter the human eye.

[0042] Understandably, after the light projected by the projection device enters the first waveguide 10, the light is transmitted within the first waveguide 10 by total internal reflection. When the light is transmitted to the first pupil dilator 11, the first pupil dilator 11 expands the light in the first direction to form an expanded light beam and directs the expanded light beam toward the optical path reversing element 30. The optical path reversing element 30 receives the expanded light beam emitted from the first pupil dilator 11 and changes the transmission direction of the expanded light beam, directing the expanded light beam toward the second waveguide 20. When the expanded light beam in the second waveguide 20 is transmitted to the second pupil dilator 21, the second pupil dilator 21 expands the expanded light beam again in the second direction and couples the expanded light beam out from the second waveguide 20 to form a two-dimensional expanded light beam, which finally enters the human eye.

[0043] It should be noted that the light path reversing element 30 is composed of optical elements that can change the direction of light transmission, such as a mirror 31, a prism, etc. The light path reversing element 30 can be composed of one optical element or multiple optical elements, and the embodiments of the present invention do not limit this.

[0044] like Figure 1 As shown, in this embodiment, the angle between the first direction and the second direction means that the first direction and the second direction are not parallel. 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°.

[0045] The inventors discovered in their research that existing two-dimensional array optical waveguides are typically a single waveguide substrate. A primary pupil dilator is located in the upper half of the waveguide substrate, and a secondary pupil dilator is located in the lower half. After the primary pupil dilator dilates the pupil, it directs the light towards the secondary pupil dilator. The secondary pupil dilator then dilates the light again and couples it out from the waveguide substrate, directing it towards the human eye. As a result, the human eye can only view the virtual image from the lower area of ​​the lens, which affects product design and results in a poor user experience.

[0046] In view of this, the optical waveguide assembly 100 according to the embodiment of the present invention, by stacking a first waveguide sheet 10 and a second waveguide sheet 20, and providing an optical path deflection element 30 at one end of the first waveguide sheet 10 and the second waveguide sheet 20, a first pupil expansion structure 11 can be provided in the first waveguide sheet 10, and a second pupil expansion structure 21 can be provided in the second waveguide sheet 20. The optical path deflection element 30 can transmit the expanded light after the first pupil expansion structure 11 to the second pupil expansion structure 21, so that the expanded light is expanded again to form a two-dimensional expanded light. Furthermore, since the first waveguide sheet 10 and the second waveguide sheet 20 are stacked, the utilization rate of the space area of ​​the front view of the first waveguide sheet 10 and the second waveguide sheet 20 is improved, the user experience is improved, and the structural design of the product is optimized.

[0047] Please continue to refer to Figure 1 In some embodiments, the first pupil-expanding structure 11 and / or the second pupil-expanding structure 21 are array beam splitters. It is understood that either the first pupil-expanding structure 11 or the second pupil-expanding structure 21 can be an array beam splitter, or both the first pupil-expanding structure 11 and the second pupil-expanding structure 21 can be array beam splitters. For example, in this embodiment, both the first pupil-expanding structure 11 and the second structure are array beam splitters. Therefore, the principle of pupil expansion achieved by array beam splitters is simple, the design concept is relatively clear, the manufacturing technology is relatively mature, the optical imaging quality is high, and there is no color cast, thereby improving imaging quality, further enhancing the user experience, and further optimizing the product's structural design.

[0048] It should be noted that multiple waveguide prisms can be obtained by cutting the waveguide substrate, and then the multiple waveguide prisms are rough ground, fine ground and polished. After that, a beam splitting film is deposited on each of the multiple waveguide prisms. Finally, the multiple waveguide prisms are glued together to form a smooth first waveguide sheet 10 or second waveguide sheet 20. At this time, the beam splitting film on the multiple waveguide prisms is located in the first waveguide sheet 10 or second waveguide sheet 20 to form an array beam splitter.

[0049] In some optional embodiments, the beam-splitting films on multiple waveguide prisms can have the same or different film systems. When the film systems of the beam-splitting films on multiple waveguide prisms are different, each array beam-splitting film can obtain different light reflection / transmission ratios, thereby controlling the intensity of each beam of light extended by the array beam-splitting mirror, thereby improving the uniformity of the image and further improving the imaging quality.

[0050] Please refer to the above as well. Figure 2 In some embodiments, the optical path deflection element 30 includes multiple reflectors 31. The extended light rays emitted from the first pupil dilator 11 pass through the multiple reflectors 31 and are then directed towards the second pupil dilator 21. Thus, by setting multiple reflectors 31, the extended light rays emitted from the first pupil dilator 11 are directed towards the second waveguide sheet 20 and then towards the second pupil dilator 21. The structure of the optical waveguide assembly 100 is simple, thereby further optimizing the structural design of the product.

[0051] Understandably, the multiple reflectors 31 can be two, three, four, five, etc. The number of reflectors 31 is not limited in this embodiment of the invention. Specifically, for example, in this embodiment, the optical path deflection element 30 may include two reflectors 31. The extended light rays emitted from the first pupil structure 11 pass through the two reflectors 31 and then are directed to the second pupil structure 21.

[0052] Please refer to the above as well. Figure 3In some embodiments, the optical path deflection element 30 includes a deflection prism 32, on which a first reflecting surface 321 and a second reflecting surface 322 are disposed. Extended light rays emitted from the first waveguide sheet 10 are reflected by the first reflecting surface 321 and then directed towards the second reflecting surface 322. The second reflecting surface 322 reflects the light rays and directs them towards the second pupil dilator structure 21. Therefore, by providing the deflection prism 32 and the first and second reflecting surfaces 321 and 322 on it for deflecting light rays, the structure of the optical waveguide assembly 100 can be further simplified, and the structural design of the product can be further optimized.

[0053] Understandably, the deflecting prism 32 can be a triangular prism, utilizing the principle of total internal reflection to form a first reflecting surface 321 and a second reflecting surface 322 on its two faces, thereby achieving the deflection of light by the prism. Alternatively, a reflective film can be deposited on the two faces of the triangular prism to form the first reflecting surface 321 and the second reflecting surface 322; or two mirrors can be attached to the two faces of the triangular prism to form the first reflecting surface 321 and the second reflecting surface 322. Of course, the deflecting prism 32 can also be a prism of other structures, as long as the deflecting prism 32 is provided with the first reflecting surface 321 and the second reflecting surface 322, it can reflect the extended light emitted from the first waveguide 10 to the second waveguide 20 and then direct it toward the second pupil dilator 21.

[0054] In some optional embodiments, the turning prism 32 is an isosceles right-angled triangular prism, with the faces corresponding to the two right-angled sides of the prism forming the first reflecting surface 321 and the second reflecting surface 322, respectively. Understandably, the faces corresponding to the two right-angled sides of the isosceles right-angled triangular prism can form the first reflecting surface 321 and the second reflecting surface 322 through total internal reflection. Alternatively, the first reflecting surface 321 and the second reflecting surface 322 can be formed by depositing a reflective film on the faces corresponding to the two right-angled sides of the isosceles right-angled triangular prism, or by attaching a mirror to the faces corresponding to the two right-angled sides of the isosceles right-angled triangular prism. Therefore, the isosceles right-angled triangular prism has a simple structure and regular shape, which can further simplify the structure of the optical waveguide assembly 100 and further optimize the product's structural design.

[0055] like Figures 5-6 As shown, in some optional embodiments, the deflection prism 32 includes a first sub-prism 323 and a second sub-prism 324, which are joined together to form the deflection prism 32. It is understood that an air gap 40 may exist between the first sub-prism 323 and the second sub-prism 324, or the first sub-prism 323 and the second sub-prism 324 may be bonded together using optical adhesive 50 to form an integral deflection prism 32.

[0056] It should be noted that in the optical path deflection element 30 formed by only two reflectors 31 or one isosceles right-angle prism, some light rays may enter the second waveguide 20 after only one reflection in the optical path deflection element 30. This part of the light rays will become ghost light rays, which will ultimately affect the imaging quality of the optical waveguide assembly 100.

[0057] Please continue to refer to Figures 4-5 In this embodiment, an air gap 40 can be provided between the deflection prism 32 formed by the first sub-prism 323 and the second sub-prism 324 and the first waveguide plate 10 and the second waveguide plate 20. Thus, when some light rays are reflected only once in the deflection prism 32 and then strike the exit surface of the deflection prism 32, the exit surface of the deflection prism 32 satisfies the condition for total internal reflection due to the air gap 40. Therefore, this portion of light cannot exit from the deflection prism 32 but is reflected again. After multiple reflections in the deflection prism 32, the total internal reflection angle condition of the exit surface of the deflection prism 32 is no longer met, and the light rays strike the second waveguide plate 20 from the exit surface of the deflection prism 32. Therefore, by providing an air gap between the deflection prism 32 formed by the first sub-prism 323 and the second sub-prism 324 and the first waveguide plate 10 and the second waveguide plate 20... Therefore, the exit surface of the turning prism 32 formed by the first sub-prism 323 and the second sub-prism 324 can form a total internal reflection surface, thereby reducing the generation of ghost light rays, improving the imaging quality of the optical waveguide assembly 100, and improving the light transmission efficiency of the optical waveguide assembly 100.

[0058] Please refer to the above as well. Figure 6 In some optional embodiments, the optical path deflection element 30 further includes a first polarizing beam splitter 35, a second polarizing beam splitter 36, and a quarter-wave plate 37. The first polarizing beam splitter 35 is provided on the side of the first sub-prism 323 facing the first waveguide 10 and the side of the second sub-prism 324 facing the second waveguide 20. The first polarizing beam splitter 35 is used to transmit light of the first polarization state and reflect light of the second polarization state. The vibration direction of the light of the first polarization state is perpendicular to that of the light of the second polarization state.

[0059] Please continue to refer to Figure 6 Furthermore, a second polarizing beam splitter 36 is disposed between the first sub-prism 323 and the second sub-prism 324. The second polarizing beam splitter 36 is used to transmit light of the second polarization state and reflect light of the first polarization state.

[0060] Please continue to refer to Figure 6 Furthermore, a quarter-wave plate 37 is provided on the side of the first reflecting surface 321 and the second reflecting surface 322 near the turning prism 32. The quarter-wave plate 37 is used to change the vibration direction of the light.

[0061] It should be noted that when the light projected by the projection device enters the first waveguide 10, the light is transmitted within the first waveguide 10 by total internal reflection. When the light is transmitted to the first pupil structure 11, the first pupil structure 11 expands the light in the first direction to form an expanded light beam and directs the expanded light beam toward the optical path reversing element 30. Since the optical path reversing element 30 includes a first sub-prism 323 and a second sub-prism 324, and both the side of the first sub-prism 323 facing the first waveguide 10 and the side of the second sub-prism 324 facing the second waveguide 20 are provided with a first polarizing beam splitter 35, when the expanded light beam is directed toward the optical path reversing element 30, the expanded light beam must pass through the first polarizing beam splitter 35. At this time, only the light beam in the first polarization state in the expanded light beam can pass through the first polarizing beam splitter 35 and enter the optical path reversing element 30.

[0062] Please continue to refer to Figure 6 Furthermore, after the light of the first polarization state enters the optical path deflection element 30, it is incident on the first reflecting surface 321. Since a quarter-wave plate 37 is provided on the side of the first reflecting surface 321 near the deflection prism 32, the light of the first polarization state passes through the quarter-wave plate 37 once when it is incident on the first reflecting surface 321, and passes through the quarter-wave plate 37 again when it exits from the first reflecting surface 321. At this time, the polarization state of the light of the first polarization state changes after passing through the quarter-wave plate 37 twice, and becomes the light of the second polarization state.

[0063] Please continue to refer to Figure 6 Furthermore, the light reflected from the first reflecting surface 321 is emitted between the first sub-prism 323 and the second sub-prism 324. At this time, the extended light is in the second polarization state. Since a second polarization beam splitter 36 is provided between the first sub-prism 323 and the second sub-prism 324, the second polarization beam splitter 36 can transmit the light in the second polarization state. Therefore, the light in the second polarization state can be emitted from the second sub-prism 324 and directed towards the second reflecting surface 322.

[0064] Please continue to refer to Figure 6 Furthermore, since a quarter-wave plate 37 is provided on the side of the second reflecting surface 322 near the turning prism 32, the light of the second polarization state passes through the quarter-wave plate 37 once when it is incident on the second reflecting surface 322, and passes through the quarter-wave plate 37 again when it exits from the second reflecting surface 322. Therefore, the polarization state of the light of the second polarization state changes after being reflected by the second reflecting surface 322, and becomes the light of the first polarization state again, and is incident on the second waveguide plate 20.

[0065] Please continue to refer to Figure 6Furthermore, since a first polarizing beam splitter 35 is provided between the second sub-prism 324 and the second waveguide 20, light in the first polarization state can enter the second waveguide 20 and be directed toward the second pupil dilator 21. After passing through the second pupil dilator 21, it exits and is directed toward the human eye, ultimately achieving augmented reality display.

[0066] Therefore, by setting the first polarizing beam splitter 35, the second polarizing beam splitter 36, and the quarter-wave plate 37, the transmission path of light is restricted. When part of the light is reflected only by the first reflecting surface 321 in the optical path turning element 30 and then shines on the second waveguide plate 20, this part of the light is in the second polarization state. This part of the light will be reflected by the first polarizing beam splitter 35 and cannot enter the second waveguide plate 20, thereby improving the imaging quality of the optical waveguide assembly 100.

[0067] It should be noted that the first polarizing beam splitter 35 can be directly formed on the surface of the first sub-prism 323 near the first waveguide plate 10 and the surface of the second sub-prism 324 near the second waveguide plate 20 by coating, or the first polarizing beam splitter can be directly pasted on the surface of the first sub-prism 323 near the first waveguide plate 10 and the surface of the second sub-prism 324 near the second waveguide plate 20. Similarly, the second polarizing beam splitter 36 can also be formed on the surface of the first sub-prism 323 near the second sub-prism 324 by coating or pasting, or the second polarizing beam splitter 36 can be formed on the surface of the second sub-prism 324 near the first sub-prism 323.

[0068] Specifically, in some embodiments, the light in the first polarization state can be p-polarized light, the light in the second polarization state can be s-polarized light, the first polarization beam splitter 35 can transmit p-polarized light and reflect s-polarized light, and the second polarization beam splitter 36 can transmit s-polarized light and reflect p-polarized light.

[0069] In some other embodiments, the projection device can project p-polarized light, in which case the extended light rays emitted from the first waveguide 10 to the optical path deflection element 30 are all p-polarized light, thereby improving the light transmission efficiency of the optical waveguide assembly 100 and further enhancing the imaging quality of the optical waveguide assembly 100.

[0070] Please refer to the above as well. Figure 7 In some embodiments, the first waveguide 10, the second waveguide 20, and the optical path deflection element 30 are bonded together using optical adhesive 50. Therefore, using optical adhesive 50 to form the optical waveguide assembly 100 as a single unit facilitates the fixation of the first waveguide 10, the second waveguide 20, and the optical path deflection element 30, preventing positional shifts in the components that could affect the optical path, thereby further optimizing the product's structural design.

[0071] It should be noted that the first waveguide 10 and the second waveguide 20 are stacked. Since it is necessary to ensure that light can be transmitted through the first waveguide 10 and the second waveguide 20 by total internal reflection, the refractive index of the optical adhesive 50 used for bonding must be lower than that of the first waveguide 10 and the second waveguide 20. This way, the light can meet the condition of total internal reflection when it is transmitted through the first waveguide 10 and the second waveguide 20.

[0072] In some optional embodiments, a coupling structure (not shown) is also included, disposed on the first waveguide 10, for coupling light into the first waveguide 10. Thus, the coupling structure allows light projected by the projection device to be coupled into the first waveguide 10 for transmission, thereby optimizing the product's structural design.

[0073] Understandably, the coupling structure can be a prism or grating disposed on the first waveguide sheet 10, and the embodiments of the present invention do not limit this.

[0074] A near-eye display device according to an embodiment of the present invention includes a projection device (not shown) and the aforementioned optical waveguide assembly 100. The projection device projects a virtual image onto the optical waveguide assembly 100. By providing the aforementioned optical waveguide assembly 100, the overall performance of the near-eye display device is improved.

[0075] Other configurations and operations of the optical waveguide assembly 100 and the near-eye display device according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0076] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0077] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0078] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0079] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0080] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0081] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An optical waveguide component, characterized in that, The optical waveguide component includes: A first waveguide sheet, wherein a first pupil expanding structure is provided within the first waveguide sheet, the first pupil expanding structure expands the light within the first waveguide sheet along a first direction to form expanded light, and emits the expanded light from the first waveguide sheet; The second waveguide sheet is stacked with the first waveguide sheet. A second pupil structure is provided inside the second waveguide sheet. The second pupil structure expands the light inside the second waveguide sheet along a second direction. There is an angle between the first direction and the second direction. An optical path deflection element is disposed at one end of the first waveguide and the second waveguide. The optical path deflection element is used to receive the extended light emitted from the first pupil dilator structure and change the transmission direction of the extended light, directing the extended light toward the second pupil dilator structure. After receiving the extended light, the second pupil dilator structure couples the extended light out from the second waveguide to form a two-dimensional extended light that enters the human eye.

2. The optical waveguide assembly according to claim 1, characterized in that, The first pupil dilator structure and / or the second pupil dilator structure are array beam splitters.

3. The optical waveguide assembly according to claim 1, characterized in that, The optical path deflection element includes multiple mirrors. The extended light rays emitted from the first pupil dilator structure pass through the multiple mirrors and then are directed toward the second pupil dilator structure.

4. The optical waveguide assembly according to claim 1, characterized in that, The optical path deflection element includes a deflection prism, on which a first reflecting surface and a second reflecting surface are provided. The extended light rays emitted from the first waveguide sheet are reflected by the first reflecting surface and then directed to the second reflecting surface. The second reflecting surface reflects the light rays and directs them to the second pupil dilator structure.

5. The optical waveguide assembly according to claim 4, characterized in that, The prism is an isosceles right-angled triangular prism, and the faces corresponding to the two right-angled sides of the isosceles right-angled triangular prism form the first reflecting surface and the second reflecting surface, respectively.

6. The optical waveguide assembly according to claim 4, characterized in that, The deflection prism includes a first sub-prism and a second sub-prism, which are spliced ​​together to form the deflection prism.

7. The optical waveguide assembly according to claim 6, characterized in that, The optical path deflection element also includes: The first polarizing beam splitter is provided on both the side of the first sub-prism facing the first waveguide and the side of the second sub-prism facing the second waveguide. The first polarizing beam splitter is used to transmit light of the first polarization state and reflect light of the second polarization state, wherein the vibration direction of the light of the first polarization state is perpendicular to that of the light of the second polarization state. The second polarizing beam splitter is disposed between the first sub-prism and the second sub-prism. The second polarizing beam splitter is used to transmit light of the second polarization state and reflect light of the first polarization state. A quarter-wave plate is provided on both the first and second reflecting surfaces near the deflecting prism, and the quarter-wave plate is used to change the vibration direction of light.

8. The optical waveguide assembly according to any one of claims 1-7, characterized in that, The first waveguide sheet, the second waveguide sheet, and the optical path deflection element are bonded together as a single unit using optical adhesive.

9. The optical waveguide assembly according to claim 8, characterized in that, It also includes a coupling structure disposed on the first waveguide sheet for coupling light into the first waveguide sheet.

10. A near-eye display device, characterized in that, The near-eye display device includes: The projection device and the optical waveguide assembly as described in any one of claims 1-9, wherein the projection device is used to emit light onto the optical waveguide assembly.

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