Optical waveguide structure and display device

Abstract

The embodiment of the application provides a kind of optical waveguide structure and display equipment, belong to optical waveguide technical field, at least one side of optical waveguide substrate has recess, stamping adhesive, protective layer are all arranged in recess, stamping adhesive forms grating structure, and protective layer covers and encapsulates grating structure.Grating structure corresponding area is grating area, other area is non-grating area, stamping adhesive, protective layer are located in grating area, non-grating area does not have stamping adhesive and protective layer, reduce the laminated structure of non-grating area, and by recess, grating structure in grating area, protective layer is embedded in optical waveguide substrate, significantly reduce the overall thickness of grating structure, protective layer and optical waveguide substrate, realize the thinning of optical waveguide structure.Laminated reduction can avoid the light loss caused by stamping adhesive, protective layer etc. in non-grating area, improve the optical performance of optical waveguide structure, and improve the light transmission of non-grating area, also can realize the weight reduction of optical waveguide structure, realize the lightweight design of optical waveguide structure.

Description

Technical Field

[0001] This application relates to the field of optical waveguide technology, and in particular to an optical waveguide structure and display device. Background Technology

[0002] Near-eye display technology can create virtual images within the field of view of one or both eyes. It uses a display device placed at a distance from the human eye's direct vision to render light field information to the eye, thereby reconstructing a virtual scene in front of the user. Among these technologies, Augmented Reality (AR) and Mixed Reality (MR) can generate immersive three-dimensional environments. Users can experience these environments using devices such as helmets, glasses, or other display devices, creating a sense of being there.

[0003] For example, taking AR glasses as an example, AR glasses can include a display module and an optical waveguide structure. The optical waveguide structure can include a substrate, a coupling grating and a coupling grating disposed on the substrate. Light emitted from the display module can be coupled into the substrate of the optical waveguide structure through the coupling grating, propagating forward in the form of total internal reflection within the substrate of the optical waveguide structure, and then coupled out through the coupling grating to the outside of the optical waveguide structure, entering the human eye for imaging, realizing the superposition of virtual images with the real environment. However, the current optical waveguide structure has a relatively thick layer thickness, resulting in a relatively bulky optical waveguide structure and display device, which is not conducive to the design of a thinner and lighter display device. Utility Model Content

[0004] This application provides an optical waveguide structure and a display device, which can realize the thin and light design of the optical waveguide structure and improve the optical performance and light transmission performance of the optical waveguide structure.

[0005] A first aspect of this application provides an optical waveguide structure, including an optical waveguide substrate, an imprinting adhesive, and a protective layer. At least one side of the optical waveguide substrate has a groove. The groove is recessed into the surface of the optical waveguide substrate and is a blind groove. In the thickness direction, the groove does not penetrate both opposite sides of the optical waveguide substrate.

[0006] The imprinting adhesive is located within the groove, forming a grating structure comprising multiple spaced-apart fences. The imprinting adhesive can be a polymer material used in imprint lithography. The polymer material is cured by imprinting using imprint lithography to form the grating structure on the imprinting adhesive. In other words, the grating structure is formed from cured imprinting adhesive, exhibiting high optical performance and being simple to mold and low in manufacturing cost.

[0007] The protective layer is positioned within the groove; that is, both the grating structure formed by the imprinted adhesive and the protective layer are located within the groove. The imprinted adhesive and the protective layer are embedded within the optical waveguide substrate through the groove, and the protective layer serves to encapsulate and cover the grating structure. Specifically, part of the protective layer covers the top of the grating structure, while another part fills the spaces between adjacent gratings, achieving comprehensive encapsulation and protection of the grating structure and improving its encapsulation and protection effect.

[0008] For example, the area on the optical waveguide substrate opposite to the grating structure is designated as the grating region, and the other areas are designated as non-grating regions. That is, the grating region of the optical waveguide substrate has stacked imprinting adhesive (grating structure) and a protective layer, while the non-grating regions of the optical waveguide substrate do not have imprinting adhesive and a protective layer. The non-grating regions may consist only of the optical waveguide substrate, reducing the stacked structure in the non-grating regions. Furthermore, by embedding the grating structure and protective layer within the optical waveguide substrate through grooves, the overall thickness of the grating structure, protective layer, and optical waveguide substrate can be significantly reduced. This reduces the overall height of the optical waveguide structure in the thickness direction (e.g., the z-direction), achieving thinning of the optical waveguide structure and facilitating thinner design of the optical waveguide structure.

[0009] The absence of imprinting adhesive and protective layers in the non-grating region avoids light absorption and loss caused by these materials, thus reducing the optical path length, improving luminous efficiency, and enhancing the optical performance of the waveguide structure. It also significantly improves the light transmittance in the non-grating region, enhancing the waveguide structure's transparency in this area. Furthermore, the reduction in the number of stacked structures in the non-grating region helps to reduce the weight of the waveguide structure, enabling a thinner and lighter design.

[0010] In one possible implementation, the side of the protective layer facing away from the grating structure is flush with the side of the optical waveguide substrate with the groove. The thickness of the entire optical waveguide structure remains consistent with the thickness of the optical waveguide substrate, allowing the optical waveguide structure to be thinned to approximately the limit value (i.e., the thickness of the optical waveguide substrate), further reducing the overall thickness of the optical waveguide structure and achieving an ultra-thin design of the optical waveguide structure.

[0011] In one possible implementation, the protective layer includes a high-hardness adhesive layer. This high-hardness adhesive layer can be a film formed after the high-hardness adhesive material has cured. It enhances the strength, rigidity, and abrasion resistance of the protective layer, providing excellent encapsulation and protection for the grating structure. This eliminates the need for additional encapsulation structures while ensuring high reliability of the optical waveguide structure, simplifies its design, and facilitates reductions in thickness and weight, enabling a thinner and lighter design.

[0012] In one possible implementation, the protective layer has a pencil hardness of 5H or higher, ensuring high hardness and providing excellent encapsulation and protection for the grating structure. This eliminates the need for additional encapsulation structures, thereby improving the reliability of the optical waveguide structure, achieving a thinner and lighter design, and enhancing its optical performance.

[0013] In one possible implementation, the difference between the refractive index of the grating structure and the refractive index of the protective layer is greater than or equal to 0.1, and the refractive index of the protective layer is less than that of the grating structure, with the difference between the two being greater than or equal to 0.1. This ensures that light can propagate well within the grating structure and the optical waveguide substrate, reduces light loss caused by the protective layer, and further improves the optical performance of the optical waveguide structure.

[0014] In one possible implementation, the thickness of the portion of the optical waveguide substrate corresponding to the groove is greater than or equal to 0.1 mm. This ensures that the portion of the optical waveguide substrate corresponding to the groove has good strength, thereby guaranteeing the high strength of the entire optical waveguide substrate and improving the reliability of the optical waveguide structure.

[0015] In one possible implementation, the ratio of the groove depth to the thickness of the optical waveguide substrate is less than or equal to 50%. By ensuring that the groove depth is less than or equal to half the thickness of the optical waveguide substrate, while maintaining high strength and reliability of the optical waveguide substrate, the groove provides relatively more space for grating structures and protective layers. The thickness of the grating structure and protective layer can be relatively thick, which is beneficial for improving the optical performance of the grating structure and the protective encapsulation effect of the grating structure, thereby enhancing the reliability and optical performance of the optical waveguide structure.

[0016] In one possible implementation, the depth of the groove ranges from 1 μm to 0.7 mm. While ensuring the high strength and high reliability of the optical waveguide substrate, the groove depth range is large, which makes it easier to meet the spatial requirements of grating structures of different thicknesses, improves the design flexibility of the grating structure, and expands the applicable range.

[0017] In one possible implementation, the refractive index of the grating structure ranges from 1.6 to 2.5. By using imprinting adhesive to form a grating structure with a high refractive index, the grating structure has a high coupling rate, which can more effectively control light and improve the optical performance of the optical waveguide structure.

[0018] In one possible implementation, the refractive index of the grating structure is greater than or equal to 1.9, ensuring that the grating structure is a high-refractive-index grating structure, thus giving the optical waveguide structure better optical performance.

[0019] In one possible implementation, there are multiple grating structures. One side of the optical waveguide substrate has multiple grooves, and the multiple grating structures are respectively disposed within these grooves. By embedding the multiple grating structures into the same surface of the optical waveguide substrate through these grooves, it is easier to encapsulate the grating structures and to place them in approximately the same environmental interface, thus ensuring the optical performance of the grating structures.

[0020] In one possible implementation, there are multiple grating structures. The two opposing surfaces of the optical waveguide substrate each have grooves, and the multiple grating structures are respectively disposed within these grooves. This allows the multiple grating structures to be embedded into the opposing surfaces of the optical waveguide substrate via these grooves, reducing the difficulty of imprinting the adhesive and molding the grating structures, and improving production yield.

[0021] In one possible implementation, the grating structure includes an input structure, an output structure, and a relay structure. The input structure is used to couple light into the optical waveguide substrate for transmission, the relay structure is used to transmit light to the output structure, and the output structure is used to couple light out to the outside of the optical waveguide structure.

[0022] The coupling-in structure and the relay structure are disposed on the same surface of the optical waveguide substrate, while the coupling-out structure is disposed on the other surface of the optical waveguide substrate. For example, the coupling-in structure and the relay structure can be located on the first surface of the optical waveguide substrate, and the coupling-out structure can be located on the second surface of the optical waveguide substrate. This facilitates the folding of the optical path and improves the optical performance of the optical waveguide structure.

[0023] In one possible implementation, the optical waveguide structure further includes a cover plate covering the grooved surface of the optical waveguide substrate, with the cover plate sealingly connected to the optical waveguide substrate. The cover plate encapsulates the grating structure, protective layer, and optical waveguide substrate. For example, if the groove is located on the first surface of the optical waveguide substrate, the cover plate can cover the grating structure, protective layer, and first surface, providing encapsulation and protection for all components. This further reduces the risk of wear and scratches to the grating structure and protective layer, and further improves the reliability and optical performance of the optical waveguide substrate.

[0024] A second aspect of this application provides a display device, including a display module and any of the aforementioned optical waveguide structures, wherein light emitted from the display module is transmitted through the optical waveguide structure.

[0025] It should be understood that the second aspect of this application corresponds to the technical solution of the first aspect of this application, and the beneficial effects achieved by each aspect and the corresponding feasible implementation are similar, and will not be repeated here. Attached Figure Description

[0026] Figure 1This is a schematic diagram illustrating the interaction between a display device and a terminal device, provided as an embodiment of this application.

[0027] Figure 2 This is a schematic diagram of the light path of an optical waveguide structure provided in an embodiment of this application;

[0028] Figure 3 This is a top view schematic diagram of an optical waveguide structure provided in an embodiment of this application;

[0029] Figure 4 for Figure 3 A top view of the assembly of the waveguide substrate and grating structure;

[0030] Figure 5 for Figure 3 A schematic cross-sectional view of the optical waveguide structure.

[0031] Figure 6 for Figure 5 A schematic diagram showing the disassembled structure of an optical waveguide;

[0032] Figure 7 This is a top view of a partial structure in another optical waveguide structure provided in an embodiment of this application;

[0033] Figure 8 for Figure 7 A schematic cross-sectional view of the optical waveguide structure.

[0034] Figure 9 A top view schematic diagram of the assembly of an optical waveguide substrate and a grating structure in another optical waveguide structure provided in an embodiment of this application;

[0035] Figure 10 A cross-sectional schematic diagram of another optical waveguide structure provided in this application embodiment;

[0036] Figure 11 for Figure 10 A schematic diagram showing the disassembled structure of the optical waveguide;

[0037] Figure 12 A top view schematic diagram of a partial structure in another optical waveguide structure provided in this application embodiment;

[0038] Figure 13 for Figure 12 A schematic cross-sectional view of the optical waveguide structure.

[0039] Figure 14 This is a schematic diagram of a fabrication method for an optical waveguide structure provided in an embodiment of this application.

[0040] Explanation of reference numerals in the attached figures:

[0041] 100 - Display devices;

[0042] 101 - Display lens; 101a - First lens; 101b - Second lens;

[0043] 10-Optical waveguide structure;

[0044] 11-Optical waveguide substrate;

[0045] 11a - First surface; 11b - Second surface; 11c - Grating region; 11d - Non-grating region; 111 - Groove;

[0046] 120 - Imprinting adhesive;

[0047] 12-grating structure; 12a-coupled-in structure; 12b-coupled-out structure; 12c-relay structure; 121-fence;

[0048] 13-Protective layer; 14-Cover plate; 15-Seal;

[0049] 102 - Structural component;

[0050] 102a - Frame; 20 - Eyeglass frame; 21 - First frame body; 22 - Second frame body; 23 - Connecting beam;

[0051] 30 - Temple; 31 - First temple; 32 - Second temple;

[0052] 103 - Display module; 103a - First module; 103b - Second module;

[0053] 200 - Terminal equipment. Detailed Implementation

[0054] The terminology used in the implementation section of this application is for the purpose of explaining specific embodiments of this application only, and is not intended to limit this application.

[0055] This application provides a display device that can project display images into the user's field of vision, thereby reconstructing a virtual scene within the field of vision.

[0056] For example, in some embodiments, the display device may include a wearable display device, which may include, but is not limited to, a virtual reality (VR) device, an augmented reality (AR) device, or a mixed reality (MR) device.

[0057] For example, a wearable display device can be a head-mounted display device, which can be worn on a user's head and used to display images in front of the user's field of vision, thereby creating a virtual scene in front of the user.

[0058] For example, taking AR head-mounted display devices as an example, AR head-mounted display devices can be used to project display images onto the user's eyes, allowing the user to simultaneously see real-world images superimposed with virtual images (i.e., the aforementioned display images), thus achieving visual fusion between virtual display images and real-world scene images.

[0059] For example, the head-mounted display device may include, but is not limited to, AR glasses, AR helmets, VR glasses, VR helmets, MR glasses, MR helmets, etc.

[0060] Alternatively, in some embodiments, the display device may include a head-up display (HUD) device, which can be applied to fields such as automotive (e.g., intelligent vehicles), aerospace (e.g., aircraft), and marine (e.g., ships).

[0061] For example, taking a head-up display (HUD) in a car as an example, an HUD can be used to display images in front of the driver's field of vision. For instance, the HUD can project the image onto the windshield, placing the image directly in front of the driver's eyes, thus avoiding the need for the driver to frequently look down at the dashboard and improving driving safety. The displayed image can include information such as vehicle speed, speed limit signs, and navigation arrows.

[0062] In this embodiment of the application, a head-mounted display device, such as AR glasses, is used as an example for illustration.

[0063] Figure 1 This is a schematic diagram illustrating the interaction between a display device and a terminal device, provided as an embodiment of this application.

[0064] For example, see Figure 1 As shown, the display device 100 may include a structural component 102 and a display lens 101. The structural component 102 can serve as the main load-bearing structural component of the display device 100, and can be used to construct the overall external structure of the display device 100. It can also be used to install and accommodate various components of the display device 100, such as the display lens 101, which is mounted on the structural component 102.

[0065] For example, in the example where the display device 100 is AR glasses, the structural component 102 may include a frame 102a. Of course, in some other embodiments, the structural component 102 may also be selectively designed according to the needs of the display device 100; for example, the structural component 102 may also be a headband, helmet, etc.

[0066] The frame 102a may include a frame 20 and temples 30. For example, the temples 30 may include a first temple 31 and a second temple 32. The first temple 31 and the second temple 32 may be respectively disposed on both sides of the frame 20, and the first temple 31 and the second temple 32 are respectively connected to the frame 20.

[0067] The display lens 101 can be disposed on the frame 20. The display lens 101 can be light-transmitting, so that light from the display environment can pass through the display lens 101 and shine into the human eye.

[0068] For example, the frame 20 may include a connecting beam 23, a first frame 21 and a second frame 22. The connecting beam 23 may be located between the first frame 21 and the second frame 22, and the first frame 21 and the second frame 22 may be connected by the connecting beam 23.

[0069] The display lens 101 may include a first lens 101a and a second lens 101b. The first lens 101a and the second lens 101b may be mounted on the first frame 21 and the second frame 22, respectively. The first temple 31 and the second temple 32 may be connected to the first frame 21 and the second frame 22, respectively.

[0070] The display device 100 is worn on the user's head. When the user wears the display device 100, the frame 20 can be located in front of the user's eyes. For example, the connecting beam 23 of the frame 20 can be attached to the user's nose, the display lens 101 installed on the frame 20 can be located directly in front of the user's eyes, and the temples 30 can be attached to the user's ears.

[0071] In some embodiments, the temple 30 and the frame 20 can be rotatably connected. For example, the display device 100 may also include a hinge structure (not shown in the figure). The first temple 31 and the second temple 32 can be connected to the frame 20 (such as the first frame 21 and the second frame 22) respectively through the hinge structure, so that the first temple 31 can rotate relative to the frame 20, and the second temple 32 can also rotate relative to the frame 20.

[0072] For example, the first temple 31 can rotate toward the frame 20, so that the first temple 31 folds relative to the frame 20. The second temple 32 can also rotate toward the frame 20, so that the second temple 32 folds relative to the frame 20. The first temple 31, the second temple 32 and the frame 20 can be folded into a multi-layered state, which facilitates the storage of the display device 100.

[0073] The first temple 31 and the second temple 32 can also be rotated away from the frame 20 to open relative to the frame 20, making it easier to wear the display device 100.

[0074] Of course, in some embodiments, the temple 30 and the frame 20 can be fixedly connected, the temple 30 and the frame 20 remain relatively fixed, and the temple 30 cannot rotate relative to the frame 20.

[0075] The display device 100 may further include a display module 103 for projecting light carrying display image information onto a display lens 101. For example, the display module 103 may include an optical engine.

[0076] The display lens 101 may include an optical waveguide structure (not shown in the figure), which can receive the light from the display module 103 and emit the light into the user's eye, thereby displaying the image in front of the user's eyes (field of vision).

[0077] The display module 103 can be disposed on the frame 20, such as at a position on the frame 20 adjacent to the temple 30. For example, the display module 103 may include a first module 103a and a second module 103b, which can be disposed on both sides of the frame 20, respectively.

[0078] For example, the first module 103a can be located on the first frame 21 near the first temple 31, and the first module 103a is used to project light onto the first lens 101a. The second module 103b can be located on the second frame 22 near the second temple 32, and the second module 103b is used to project light onto the second lens 101b. The light is then directed into the user's eyes through the waveguide structure of the first lens 101a and the second lens 101b.

[0079] like Figure 1 As shown, the display device 100 can communicate with the terminal device 200. For example, the terminal device 200 may include, but is not limited to, electronic terminal devices such as mobile phones, tablets, laptops, desktop computers, and netbooks.

[0080] The display device 100 and the terminal device 200 can communicate with each other via wired or wireless means, enabling interaction between the display device 100 and the terminal device 200. For example, the terminal device 200 can select and control the display image of the display device 100.

[0081] In some embodiments, the entire area of ​​the display lens 101 may have an optical waveguide structure, or in some embodiments, a portion of the display lens 101 may have an optical waveguide structure. Both display lenses 101 may include the optical waveguide structure 10, or only one of the display lenses 101 may include the optical waveguide structure.

[0082] Figure 2This is a schematic diagram of the light path of an optical waveguide structure provided in an embodiment of this application. It should be noted that... Figure 2 This is only used to illustrate the propagation path of light in the optical waveguide structure 10, and is not used to define the structure and assembly relationship of the coupling structure 12a, coupling structure 12b, and optical waveguide substrate 11 in the optical waveguide structure 10.

[0083] In some embodiments, see Figure 2 As shown, the optical waveguide structure 10 may include an optical waveguide substrate 11, a coupling structure 12a, and a coupling structure 12b. The coupling structure 12a and the coupling structure 12b may be respectively disposed on the optical waveguide substrate 11. The light emitted from the display module 103 can be projected onto the coupling structure 12a, and the light is coupled into the optical waveguide substrate 11 through the coupling structure 12a. The light can undergo total internal reflection within the optical waveguide substrate 11, and the light propagates forward in the form of total internal reflection within the optical waveguide substrate 11, and then is coupled out to the outside of the optical waveguide substrate 11 through the coupling structure 12b, whereby the coupling structure 12b emits the light and thus enters the user's eye 300 for imaging.

[0084] Currently, the coupling-in structure and coupling-out structure are usually gratings. The coupling-in structure and coupling-out structure are stacked on one side of the optical waveguide substrate. The coupling-in structure and coupling-out structure protrude from one side of the optical waveguide substrate, making the optical waveguide structure thicker, resulting in a thicker and heavier optical waveguide structure and display device.

[0085] Based on this, embodiments of this application provide an optical waveguide structure comprising an optical waveguide substrate, an imprinting adhesive, and a protective layer. At least one side of the optical waveguide substrate has a groove, which is a blind groove that does not penetrate both opposite sides of the optical waveguide substrate. The imprinting adhesive and the protective layer are disposed within the groove. The imprinting adhesive forms a grating structure, and the protective layer covers and encapsulates the grating structure. Part of the protective layer covers the top of the grating structure, while part fills the spaces between the grating gates, achieving comprehensive encapsulation and protection of the grating structure. The area on the optical waveguide substrate opposite the grating structure is designated as the grating, and other areas are designated as non-grating areas. That is, the grating area has stacked imprinting adhesive (grating structure) and a protective layer, while the non-grating areas do not have imprinting adhesive and a protective layer, reducing the stacked structure in the non-grating areas. Furthermore, the grating structure and protective layer within the grating area are embedded into the optical waveguide substrate through the groove, significantly reducing the overall thickness of the grating structure, protective layer, and optical waveguide substrate, thus achieving a thinner optical waveguide structure. It can also avoid light absorption and loss caused by imprinting adhesive and protective layers in non-grating areas, thus improving the optical performance of the optical waveguide structure and significantly enhancing the light transmittance in non-grating areas. In addition, the reduction of stacked structures in non-grating areas also helps to reduce the weight of the optical waveguide structure, enabling a thinner and lighter design.

[0086] Figure 3This is a top view schematic diagram of an optical waveguide structure provided in an embodiment of this application. Figure 4 for Figure 3 A top view of the assembly of the waveguide substrate and grating structure.

[0087] For example, see Figure 3 As shown, the optical waveguide structure 10 includes an optical waveguide substrate 11, a grating structure (not shown in the figure), and a protective layer 13. The optical waveguide substrate 11 can serve as the main load-bearing structural component of the entire optical waveguide structure 10. The grating structure and the protective layer 13 are respectively assembled on the optical waveguide substrate 11.

[0088] The grating structure can be used to control the direction of light, allowing light to couple into or out of the optical waveguide structure 10. The protective layer 13 can encapsulate and protect the grating structure, preventing it from being exposed on the optical waveguide substrate 11 and causing damage.

[0089] In some embodiments, see Figure 4 As shown, the number of grating structures 12 can be multiple, such as... Figure 4 An example of three grating structures 12 is shown. For example, grating structure 12 may include an input structure 12a, an output structure 12b, and a relay structure 12c.

[0090] The coupling structure 12a is used to couple the light emitted from the display module 103 (not shown) into the optical waveguide substrate 11. The light emitted from the display module 103, including the displayed image information, can be projected onto the coupling structure 12a, which couples the light into the optical waveguide substrate 11. The light propagates within the optical waveguide substrate 11 via total internal reflection and then to the relay structure 12c. The relay structure 12c acts as a relay for the light, enabling optical path correction, aberration optimization, and resulting in a more uniform and clearer image formed by the light output from the optical waveguide structure 10.

[0091] The relay structure 12c can transmit light to the coupling structure 12b, which can couple the light out to the outside of the optical waveguide substrate 11, and then emit it from the optical waveguide structure 10 into the user's eye to form an image, thus displaying the image in front of the user's eyes.

[0092] Of course, in some other embodiments, the grating structure 12 may only include the coupling-in structure 12a and coupling-out structure 12b described above. Alternatively, in some embodiments, the number of grating structures 12 may be more than three. For example, the grating structure 12 may also include a folded grating structure, a uniform grating structure, etc.

[0093] Figure 5 for Figure 3 A cross-sectional schematic diagram of the optical waveguide structure. Figure 5The cross-section formed by cutting the optical waveguide structure 10 along the plane containing the thickness direction of the optical waveguide substrate 11.

[0094] In the embodiments of this application, for ease of description, as follows: Figure 5 As shown in the figure, the z-direction is defined as the thickness direction of the optical waveguide substrate 11. The optical waveguide substrate 11 can be a quasi-planar structure; for example, the optical waveguide substrate 11 can include a plate-shaped glass plate.

[0095] For example, the material of the optical waveguide substrate 11 may include a high refractive index material, such as a high refractive index glass plate. This ensures that light can propagate within the optical waveguide substrate 11 via total internal reflection, thus guaranteeing the optical performance of the optical waveguide structure 10.

[0096] In this embodiment, the refractive index and thickness of the optical waveguide substrate 11 are not limited and can be selectively set according to actual needs. For example, in some embodiments, the thickness of the optical waveguide substrate 11 can range from 0.3 mm to 1.5 mm, such as 0.8 mm, which ensures the optical performance of the optical waveguide substrate 11 while facilitating the thinning design of the optical waveguide structure 10.

[0097] The optical waveguide substrate 11 may include two opposing sides, such as a first surface 11a and a second surface 11b. For example, in the thickness direction (e.g., the z-direction), the first surface 11a and the second surface 11b may be located on opposite sides of the optical waveguide substrate 11, and the first surface 11a and the second surface 11b are arranged opposite to each other in the thickness direction (e.g., the z-direction).

[0098] The grating structure 12 can be disposed on at least one side of the optical waveguide substrate 11. For example, multiple grating structures 12 can be disposed on one side of the optical waveguide substrate 11, such as on the first surface 11a (see reference). Figure 4 (As shown). It should be noted that, Figure 5 The image shows only one example of a grating structure 12 disposed on the first surface 11a of the optical waveguide substrate 11, such as the grating structure 12 being a coupling structure 12a.

[0099] The following uses the coupling structure 12a as an example to illustrate the structure of the grating structure 12 and its assembly method on the optical waveguide substrate 11. The structure of other grating structures 12 (such as the coupling structure 12b, the relay structure 12c, etc.) and their assembly methods on the optical waveguide substrate 11 can be referred to the coupling structure 12a.

[0100] Figure 6 for Figure 5 A schematic diagram showing the breakdown of an optical waveguide structure.

[0101] See Figure 6 As shown, a groove 111 is formed on at least one side of the optical waveguide substrate 11. The groove 111 is recessed into the surface of the optical waveguide substrate 11. The groove 111 is a blind groove, and in the thickness direction (such as the z-direction), the groove 111 does not penetrate the two opposite sides of the optical waveguide substrate 11. For example, the groove 111 can be formed on the first surface 11a of the optical waveguide substrate 11. The opening of the groove 111 can be located on the first surface 11a, and the groove 111 does not penetrate to the second surface 11b of the optical waveguide substrate 11.

[0102] The groove 111 may include a bottom surface 1111 and a side wall surface 1112. The side wall surface 1112 is disposed around one side of the bottom surface 1111 to enclose the space within the groove 111. In the thickness direction (e.g., the z-direction), the bottom surface 1111 of the groove 111 is lower than the first surface 11a of the optical waveguide substrate 11. For example, taking the second surface 11b as a reference surface, in the thickness direction (e.g., the z-direction), the distance from the bottom surface 1111 of the groove 111 to the second surface 11b is less than the distance from the first surface 11a to the second surface 11b.

[0103] In the thickness direction (such as the z direction), the thickness of the portion of the optical waveguide substrate 11 corresponding to the groove 111 is less than the thickness of the optical waveguide substrate 11 in other regions, that is, the portion of the optical waveguide substrate 11 located below the bottom surface 1111 of the groove 111 is thinner.

[0104] The optical waveguide structure 10 also includes an imprinting adhesive 120, combined with... Figure 5 As shown, the imprinting adhesive 120 can be disposed within the groove 111. The imprinting adhesive 120 can be a polymer material used in imprint lithography. For example, before molding, the polymer material can be in a liquid state. During the imprinting process using an imprinting mold or the like, the polymer material can be solidified by external forces to form the imprinting adhesive 120. The pattern on the mold can be precisely replicated on the imprinting adhesive 120, thereby forming a structure of the desired shape.

[0105] Imprint lithography 120 forms a grating structure 12, which includes multiple spaced-apart fences 121. Specifically, the grating structure 12 is formed on the imprint lithography 120 by imprinting and curing polymer material. In other words, the grating structure 12 is formed from the cured imprint lithography 120. The grating structure 12 formed using imprint lithography 120 has high precision in shape and pattern, ensuring high optical performance. It is also suitable for manufacturing complex grating structures 12, offering a wider range of applications. Furthermore, the molding process is simple, the manufacturing cost is low, and it is easily implemented in industrial processing.

[0106] A grating structure 12 formed by imprinting adhesive 120 is disposed in a groove 111. For example, the grating structure 12 can be located on the bottom surface of the groove 111, so that the grating structure 12 is embedded in the optical waveguide substrate 11 through the groove 111.

[0107] For example, liquid polymer material can be placed in the groove 111 of the optical waveguide substrate 11 using a dispensing process, and then imprinted using an imprinting mold. After curing, an imprinting adhesive 120 with a pattern such as a grating 121 is formed, and the imprinting adhesive 120 forms a grating structure 12.

[0108] It should be noted that in examples with multiple grating structures 12, the material, number of fences 121, shape of fences 121, and spacing between fences 121 of the different grating structures 12 can vary. These can be selectively set according to the function of the grating structure 12.

[0109] For example, continue to combine Figure 5 and Figure 6 As shown, the optical waveguide substrate 11 may include a grating region 11c and a non-grating region 11d. In the thickness direction (e.g., the z-direction), the region opposite to the grating structure 12 can be the grating region 11c, and other regions on the optical waveguide substrate 11 can be the non-grating region 11d. That is, the vertical projection of the grating structure 12 on the optical waveguide substrate 11 can coincide with the grating region 11c, and the groove 111 is located within the grating region 11c.

[0110] It should be noted that, in the context of the embodiments of this application, terms such as "overlapping", "aligned", "consistent", "equal", and "covering" all refer to "overlapping", "aligned", "consistent", "equal", and "covering" within a reasonable range of processing and / or assembly tolerances.

[0111] Continue to combine Figure 5 and Figure 6 As shown, the protective layer 13 is disposed on the side of the optical waveguide substrate 11 with the grating structure 12. The protective layer 13 is disposed in the groove 111, so that the protective layer 13 is embedded in the optical waveguide substrate 11 through the groove 111. The protective layer 13 is located in the grating region 11c.

[0112] The protective layer 13 can be located on the side of the grating structure 12 facing away from the bottom surface of the groove 111, that is, in the thickness direction (e.g., the z-direction), the imprinting adhesive 120 (grating structure 12) and the protective layer 13 are sequentially stacked on the bottom surface 1111 of the groove 111. The protective layer 13 covers and encapsulates the grating structure 12, thereby protecting the grating structure 12. This can reduce or avoid the risk of wear and scratches to the grating structure 12, improve the durability and reliability of the optical waveguide structure 10, ensure the optical performance of the optical waveguide structure 10, and extend its service life.

[0113] For example, the protective layer 13 fills the groove 111 to encapsulate the grating structure 12. Part of the protective layer 13 can fill between adjacent gratings 121, and part of the protective layer 13 can cover the side of the grating structure 12 facing away from the bottom surface 1111 of the groove 111, thereby achieving full encapsulation and protection of the grating structure 12 and improving the encapsulation and protection effect of the grating structure 12.

[0114] It is understandable that, in the example where the fence 121 of the grating structure 12 is in contact with the sidewall 1112 of the groove 111, the protective layer 13 partially fills the spaces between adjacent fences 121, and partially covers the top of the grating structure 12. In the example where there is a gap between the fence 121 of the grating structure 12 and the sidewall 1112 of the groove 111, such as... Figure 5 and Figure 6 As shown, a portion of the protective layer 13 fills between adjacent fences 121, a portion of the protective layer 13 covers the grating structure 12, and a portion of the protective layer 13 also fills between the fences 121 and the sidewalls 1112 of the grooves 111, so as to achieve full encapsulation of the grating structure 12.

[0115] The grating structure 12 and the protective layer 13 formed by the imprinting adhesive 120 are both located in the groove 111. The thickness and distribution area of ​​the imprinting adhesive 120 and the protective layer 13 are controllable. The imprinting adhesive 120 (grating structure 12) and the protective layer 13 are stacked only in the grating region 11c (groove 111) of the optical waveguide substrate 11. The non-grating region 11d of the optical waveguide substrate 11 does not have the imprinting adhesive 120 and the protective layer 13. The non-grating region 11d can include only the optical waveguide substrate 11, reducing the stacked structure of the non-grating region 11d. Furthermore, by embedding the grating structure 12 and the protective layer 13 in the grating region 11c into the optical waveguide substrate 11 through the groove 111, the overall thickness of the grating structure 12, the protective layer 13 and the optical waveguide substrate 11 can be significantly reduced, thereby reducing the overall height of the optical waveguide structure 10 in the thickness direction (such as the z direction), achieving the thinning of the optical waveguide structure 10, which is beneficial for realizing the thinning design of the optical waveguide structure 10.

[0116] The non-grating region 11d lacks the imprinting adhesive 120 and protective layer 13, thus preventing light absorption and loss caused by the imprinting adhesive 120 and protective layer 13 within the non-grating region 11d. This reduces the optical path length, improves optical efficiency, and enhances the optical performance of the optical waveguide structure 10. It also significantly improves the light transmittance of the non-grating region 11d, enhancing the transparency of the optical waveguide structure 10 within this region. Furthermore, the reduction in the number of stacked structures within the non-grating region 11d helps to reduce the weight of the optical waveguide structure 10, enabling a thinner and lighter design.

[0117] It should be noted that in the example where there are multiple grating structures 12, there can be multiple grooves 111 on the optical waveguide substrate 11. Each groove 111 is provided with imprinting adhesive 120, and the imprinting adhesive 120 in multiple grooves 111 respectively forms multiple grating structures 12, so that multiple grooves 111 have multiple grating structures 12 respectively.

[0118] Each groove 111 is provided with a protective layer 13, and multiple protective layers 13 encapsulate and cover multiple grating structures 12, thereby protecting the multiple grating structures 12.

[0119] In some embodiments, such as Figure 5 As shown, the side of the protective layer 13 facing away from the grating structure 12 can be flush with the side of the optical waveguide substrate 11 with the groove 111. For example, taking the first surface 11a of the optical waveguide substrate 11 as an example, the protective layer 13 and the grating structure 12 are accommodated in the groove 111, the protective layer 13 covers the grating structure 12, and the side of the protective layer 13 facing away from the grating structure 12 can be flush with the first surface 11a.

[0120] For example, using the second surface 11b as a reference surface, in the thickness direction (e.g., the z-direction), the distance from the side of the protective layer 13 facing away from the grating structure 12 to the second surface 11b can be approximately equal to the distance from the first surface 11a to the second surface 11b. The thickness of the entire optical waveguide structure 10 remains consistent with the thickness of the optical waveguide substrate 11, allowing the optical waveguide structure 10 to be thinned to approximately the limit value (i.e., the thickness of the optical waveguide substrate 11), further reducing the overall thickness of the optical waveguide structure 10 and achieving an ultra-thin design of the optical waveguide structure 10.

[0121] Of course, in some other embodiments, the side of the protective layer 13 facing away from the grating structure 12 may be lower than the side of the optical waveguide substrate 11 with the groove 111.

[0122] For example, taking the first surface 11a of the optical waveguide substrate 11 as an example with a groove 111, and taking the second surface 11b as a reference surface, in the thickness direction (such as the z direction), the distance from the side of the protective layer 13 facing away from the grating structure 12 to the second surface 11b can be less than the distance from the first surface 11a to the second surface 11b, so that the overall thickness of the optical waveguide substrate 11, the grating structure 12, and the protective layer 13 in the grating region 11c is less than the thickness of the optical waveguide substrate in the non-grating region 11d.

[0123] The maximum thickness of the entire optical waveguide structure 10 can also be kept consistent with the thickness of the optical waveguide substrate 11, realizing the ultra-thin design of the optical waveguide structure 10. Furthermore, it enriches the design of the optical waveguide structure 10 and meets the application requirements in various scenarios.

[0124] In some embodiments, the protective layer 13 may include a high-hardness adhesive layer, which may be a film layer formed after the high-hardness adhesive material has been cured. For example, high-hardness adhesive material may be filled into the groove 111 with the grating structure 12 by dispensing, and after curing, a high-hardness adhesive layer is formed, which covers and encapsulates the grating structure 12.

[0125] The protective layer 13 can improve the strength, rigidity and wear resistance, and can effectively encapsulate and protect the grating structure 12. No additional encapsulation structure is needed, ensuring the high reliability of the optical waveguide structure 10. This simplifies the structural design of the optical waveguide structure 10, making it easier to reduce the thickness and weight of the optical waveguide and achieve a thinner and lighter design.

[0126] Furthermore, an encapsulation structure, such as an encapsulated lens, is provided. The encapsulation structure is fixed to the side of the optical waveguide substrate 11 with the grating structure 12 by encapsulating adhesive or the like. There is usually an air layer between the encapsulation structure and the first surface 11a (and the grating structure 12), which will cause loss of light efficiency. The air layer is in long-term contact with the grating structure 12 and is also prone to contamination and damage to the grating structure 12, which will reduce optical performance.

[0127] In this embodiment, a protective layer 13 is used as the encapsulation structure. The protective layer 13 can be directly covered on the grating structure 12. There is no air layer between the protective layer 13 and the grating structure 12. While ensuring the high reliability of the optical waveguide structure 10, it can also improve the light efficiency, reduce or avoid the contact between the grating structure 12 and the air, and help improve the optical performance of the optical waveguide structure 10.

[0128] For example, the pencil hardness of the protective layer 13 can be greater than or equal to 5H, ensuring that the protective layer 13 has high hardness and can provide good encapsulation protection for the grating structure 12. Without the need for additional encapsulation structures, the optical waveguide structure 10's light performance is improved while further enhancing its reliability and achieving a thinner and lighter design.

[0129] In some embodiments, the difference between the refractive index of the grating structure 12 and the refractive index of the protective layer 13 can be greater than or equal to 0.1, and the refractive index of the protective layer 13 is less than the refractive index of the grating structure 12, with the difference between the two being greater than or equal to 0.1. This ensures that light can propagate well within the grating structure 12 and the optical waveguide substrate 11, reduces the light loss caused by the protective layer 13, and further improves the optical performance of the optical waveguide structure 10.

[0130] For example, the protective layer 13 can be made of a low-refractive-index, high-hardness adhesive layer.

[0131] For example, the refractive index range of the protective layer 13 may include 1.0 to 1.4, so that the refractive index of the protective layer 13 is relatively small, further reducing optical loss and improving the optical performance of the optical waveguide structure 10.

[0132] In some embodiments, the thickness of the portion of the optical waveguide substrate 11 corresponding to the groove 111 can be greater than or equal to 0.1 mm. The portion of the optical waveguide substrate 11 corresponding to the groove 111 can refer to the area in the thickness direction (e.g., the z-direction) that coincides with the vertical projection of the groove 111 onto the optical waveguide substrate 11, that is, the portion of the optical waveguide substrate 11 located below the bottom surface 1111 of the groove 111 in the thickness direction (e.g., the z-direction).

[0133] For example, see Figure 6 As shown, the thickness of the portion of the optical waveguide substrate 11 corresponding to the groove 111 can be h1, and this portion of the optical waveguide substrate 11 is thinner than the optical waveguide substrate 11 in other areas. Making h1 ≥ 0.1 mm can ensure that the portion of the optical waveguide substrate 11 corresponding to the groove 111 has good strength, thereby ensuring the high strength of the entire optical waveguide substrate 11 and improving the reliability of the optical waveguide structure 10.

[0134] In some embodiments, the ratio of the depth of the groove 111 to the thickness of the optical waveguide substrate 11 can be less than or equal to 50%, wherein the depth of the groove 111 can refer to the height of the space within the groove 111 in the thickness direction (such as the z-direction).

[0135] The depth of the groove 111 is less than or equal to the thickness of the optical waveguide substrate 11. Under the condition of ensuring that the optical waveguide substrate 11 has high strength and high reliability, the groove 111 has relatively more space to set the grating structure 12 and the protective layer 13. The thickness of the grating structure 12 and the protective layer 13 can be relatively thick, which is beneficial to improving the optical performance of the grating structure 12 and the protective packaging effect of the grating structure 12, thereby improving the reliability and optical performance of the optical waveguide structure 10.

[0136] For example, the depth range of the groove 111 may include 1μm to 0.7mm. Under the condition of ensuring that the optical waveguide substrate 11 has high strength and high reliability, the groove 111 has a large depth range, which makes it easier to meet the space requirements of grating structures 12 with different thicknesses, improve the design flexibility of grating structures 12, and expand the applicable range.

[0137] For example, the depth of the groove 111 can be 0.1 mm, which makes the optical waveguide substrate 11 strong and reliable, and has more space to set the grating structure 12 and the protective layer 13, so that the optical waveguide structure 10 can achieve good optical performance.

[0138] In some embodiments, the refractive index range of the grating structure 12 may include 1.6 to 2.5. The grating structure 12 with a high refractive index is formed by using the imprinting adhesive 120. The grating structure 12 has a high coupling rate, which can more effectively control light and improve the optical performance of the optical waveguide structure 10.

[0139] For example, the refractive index range of the grating structure 12 can be greater than or equal to 1.9, ensuring that the grating structure 12 is a high refractive index grating structure 12, so that the optical waveguide structure 10 has better optical performance.

[0140] For example, the refractive index of the grating structure 12 can be 1.9, which ensures that the optical waveguide structure 10 has good optical performance and facilitates the molding of the grating structure 12, reducing the manufacturing difficulty and cost of the grating structure 12.

[0141] Figure 7 This is a top view schematic diagram of a partial structure in another optical waveguide structure provided in an embodiment of this application. Wherein, Figure 7 The protective layer is not shown in the figure. The dashed lines in the figure are used to indicate the internal structural layout of the optical waveguide structure.

[0142] In some embodiments, see Figure 7 As shown, the optical waveguide structure 10 may also include a cover plate 14, which is used to encapsulate the grating structure 12, the protective layer 13 and the optical waveguide substrate 11.

[0143] Figure 8 for Figure 7 A cross-sectional schematic diagram of the optical waveguide structure.

[0144] See Figure 8 As shown, the cover plate 14 covers the side of the optical waveguide substrate 11 with the groove 111. For example, taking the multiple grating structures 12 located on the first surface 11a of the optical waveguide substrate 11 as an example, the first surface 11a of the optical waveguide substrate 11 has a groove 111, and the groove 111 is stacked with imprinting adhesive 120 (grating structure 12) and protective layer 13.

[0145] The cover plate 14 covers the first surface 11a of the optical waveguide substrate 11. The cover plate 14 can cover the grating structure 12, the protective layer 13 and the first surface 11a, and play a role in encapsulating and protecting the grating structure 12, the protective layer 13 and so on. It can further reduce the risk of wear and scratches on the grating structure 12, the protective layer 13 and so on, and further improve the reliability and light performance of the optical waveguide substrate 11.

[0146] For example, the cover plate 14 and the optical waveguide substrate 11 can be sealed together, so that a sealed space is formed between the cover plate 14 and the optical waveguide substrate 11 (such as the first surface 11a), preventing moisture, pollutants and other substances in the environment from coming into contact with the grating structure 12, the protective layer 13 and so on, thereby further improving the encapsulation and protection effect of the grating structure 12, the protective layer 13 and so on, and helping to improve the reliability and light performance of the optical waveguide structure 10.

[0147] For example, such as Figure 8 As shown, the optical waveguide structure 10 may further include a sealing element 15, through which the cover plate 14 and the optical waveguide substrate 11 can be sealed together. Exemplarily, the sealing element 15 may include, but is not limited to, sealant, gasket, or sealing ring.

[0148] In an example where there are multiple grating structures 12, for instance, the multiple grating structures 12 can all be disposed on the same surface of the optical waveguide substrate 11. For example, the multiple grating structures 12 exemplified above can be disposed on the first surface 11a of the optical waveguide substrate 11 (see reference). Figure 4 As shown in the figure. This facilitates the encapsulation of the grating structure 12 and places multiple grating structures 12 in approximately the same environmental interface, which helps to ensure the optical performance of the grating structure 12.

[0149] Multiple grating structures 12 are respectively embedded in the optical waveguide substrate 11 through grooves 111. That is, one side of the optical waveguide substrate 11 may have multiple grooves 111, and the multiple grating structures 12 are respectively located in the multiple grooves 111. Taking the multiple grating structures 12 as being disposed on the first surface 11a of the optical waveguide substrate 11 as an example, the first surface 11a may have multiple grooves 111, and each groove 111 is stacked with imprinting adhesive 120 (grating structure 12) and protective layer 13.

[0150] For example, taking multiple grating structures 12 including the aforementioned coupling structure 12a, relay structure 12c, and coupling structure 12b as an example, three grooves 111 can be respectively formed on the first surface 11a of the optical waveguide substrate 11. The coupling structure 12a, relay structure 12c, and coupling structure 12b can be respectively disposed in the three grooves 111. Each groove 111 also has a protective layer 13, which covers and encapsulates the coupling structure 12a, relay structure 12c, and coupling structure 12b respectively.

[0151] The assembly method of the grating structure 12, protective layer 13, etc. on the optical waveguide substrate 11 and the corresponding beneficial effects can be found above, and will not be repeated here.

[0152] Alternatively, in some embodiments, multiple grating structures 12 can be respectively disposed on two opposite sides of the optical waveguide substrate 11. For example, multiple grating structures 12 can be respectively disposed on the first surface 11a and the second surface 11b of the optical waveguide substrate 11, which helps to reduce the molding difficulty of the imprinting adhesive 120 and the grating structure 12 and improve the production yield.

[0153] Figure 9 This is a top view schematic diagram of the assembly of an optical waveguide substrate and a grating structure in another optical waveguide structure provided in an embodiment of this application.

[0154] For example, such as Figure 9 The diagram shows a top view of the structure of the optical waveguide substrate 11 from the first surface 11a side. Solid lines indicate grating structures 12 observable on the first surface 11a of the optical waveguide substrate 11, and dashed lines indicate grating structures 12 on the second surface 11b of the optical waveguide substrate 11. That is, among the multiple grating structures 12, some grating structures 12 are located on the first surface 11a of the optical waveguide substrate 11, and some optical waveguide substrates 11 are located on the second surface 11b of the optical waveguide substrate 11.

[0155] In examples where multiple grating structures 12 include the aforementioned coupling-in structure 12a, relay structure 12c, and coupling-out structure 12b, exemplarily, such as... Figure 9 As shown, the coupling structure 12a and the relay structure 12c can be located on the same surface of the optical waveguide substrate 11, and the coupling structure 12b can be located on another surface of the optical waveguide substrate 11. For example, the coupling structure 12a and the relay structure 12c can be located on the first surface 11a of the optical waveguide substrate 11, and the coupling structure 12b can be located on the second surface 11b of the optical waveguide substrate 11. This facilitates the folding of the optical path and improves the optical performance of the optical waveguide structure 10.

[0156] Figure 10 This is a cross-sectional schematic diagram of another optical waveguide structure provided in an embodiment of this application. Figure 11 for Figure 10 A schematic diagram showing the disassembly of the optical waveguide structure.

[0157] Combination Figure 10 and Figure 11 As shown, multiple grating structures 12 are respectively embedded in the optical waveguide substrate 11 via grooves 111. See also Figure 11As shown, grooves 111 can be formed on both sides of the optical waveguide substrate 11. Each groove 111 contains a grating structure 12 formed by imprinting adhesive 120 and a protective layer 13. The bottom surface of the groove 111 in the grating region 11c of the optical waveguide substrate 11 is provided with imprinting adhesive 120 (grating structure 12) and a protective layer 13. The non-grating region 11d of the optical waveguide substrate 11 does not contain imprinting adhesive 120 (grating structure 12) and a protective layer 13.

[0158] For example, in a plurality of grating structures 12 including the aforementioned coupling-in structure 12a, relay structure 12c, and coupling-out structure 12b, in order to Figure 11 Taking the relay structure 12c and coupling structure 12b shown as examples, a groove 111b can be formed on the first surface 11a of the optical waveguide substrate 11. The relay structure 12c formed by the imprinting adhesive 120 and the protective layer 13 can be sequentially stacked in the groove 111b, and the protective layer 13 encapsulates the relay structure 12c. A groove 111a can be formed on the second surface 11b of the optical waveguide substrate 11. The coupling structure 12b formed by the imprinting adhesive 120 and the protective layer 13 can be sequentially stacked in the groove 111a, and the protective layer 13 encapsulates and protects the coupling structure 12b.

[0159] The assembly method of the grating structure 12, protective layer 13, etc. on the optical waveguide substrate 11 and the corresponding beneficial effects can be found above, and will not be repeated here.

[0160] Figure 12 This is a top view schematic diagram of a partial structure in another optical waveguide structure provided in an embodiment of this application, wherein, Figure 12 The protective layer 13 is not shown in the figure. The dashed lines in the figure are used to indicate the internal structural layout of the optical waveguide structure 10. The same type of dashed lines are used to indicate that the grating structure 12 is located on the same side (such as the first surface 11a) of the optical waveguide substrate 11, and different types of dashed lines are used to indicate that the grating structure 12 is located on different sides of the optical waveguide substrate 11.

[0161] In an example where multiple grating structures 12 are located on opposite sides of the optical waveguide substrate 11, see [reference needed]. Figure 12 As shown, the optical waveguide structure 10 may also include a cover plate 14, which encapsulates the grating structure 12, the protective layer 13, and the optical waveguide substrate 11. This further reduces the risk of wear and scratches on the grating structure 12 and the protective layer 13, and further improves the reliability and optical performance of the optical waveguide substrate 11.

[0162] Figure 13 for Figure 12 A cross-sectional schematic diagram of the optical waveguide structure.

[0163] See Figure 13As shown, the cover plate 14 covers the side of the optical waveguide substrate 11 with the groove 111, that is, the cover plate 14 is covered on both opposite sides of the optical waveguide substrate 11. In the thickness direction (such as the z direction), the cover plate 14 covers both sides of the optical waveguide substrate 11.

[0164] For example, there can be two cover plates 14. One cover plate 14 can cover the first surface 11a of the optical waveguide substrate 11. The cover plate 14 can cover part of the grating structure 12 (such as the coupling structure 12a and the relay structure 12c), the protective layer 13 and the first surface 11a, and play a role in encapsulating and protecting the part of the grating structure 12, the protective layer 13, etc.

[0165] Another cover plate 14 can also cover the second surface 11b of the optical waveguide substrate 11. The cover plate 14 can cover another part of the grating structure 12 (such as the coupling structure 12b), the protective layer 13, and the second surface 11b, and play a role in encapsulating and protecting the grating structure 12, the protective layer 13, etc.

[0166] For example, the cover plate 14 can be sealed to the optical waveguide substrate 11, forming a sealed space between the cover plate 14 and the optical waveguide substrate 11. The specific sealing connection method and the corresponding beneficial effects can be found above, and will not be repeated here.

[0167] This application also provides a method for fabricating an optical waveguide structure, used to fabricate the aforementioned optical waveguide structure 10.

[0168] Figure 14 This is a schematic diagram of a fabrication method for an optical waveguide structure provided in an embodiment of this application. See also... Figure 14 As shown, the method may include the following steps:

[0169] Step S101: Provide an optical waveguide substrate and form a groove on at least one side of the optical waveguide substrate.

[0170] For example, grooves can be formed on at least one side of the optical waveguide substrate by means of etching, cutting, or other methods. The structure of the optical waveguide substrate and the grooves can be found above and will not be repeated here.

[0171] In an example where a grating structure is disposed on one side of an optical waveguide substrate, a groove can be formed on one side of the optical waveguide substrate, such as forming a groove on the first surface. In an example where multiple grating structures are respectively located on two sides of the optical waveguide substrate, grooves can be formed on opposite sides of the optical waveguide substrate, such as having grooves on both the first and second surfaces.

[0172] Step S102: Apply imprinting adhesive to the groove and form a grating structure with the imprinting adhesive.

[0173] For example, liquid polymer material can be placed in a groove using a method such as inkjet dispensing, and the polymer material can be imprinted and cured using an imprinting process to form an imprinting adhesive. Patterns such as fences can be formed on the imprinting adhesive to form a grating structure.

[0174] The grating structure may include multiple spaced gratings. The specific structure of the grating structure and its positional relationship with the groove and the optical waveguide substrate can be found above and will not be repeated here.

[0175] Step S103: Set a protective layer in the groove, and the protective layer encapsulates the grating structure.

[0176] For example, adhesive material (such as the high-hardness adhesive material mentioned above) can be filled into the groove by means of dispensing, and after curing, a protective layer is formed, which can encapsulate and cover the grating structure.

[0177] The protective layer partially covers the grating structure and partially fills the spaces between adjacent gratings. The structure of the protective layer and its positional relationship with the grating structure and the waveguide substrate can be found above and will not be repeated here.

[0178] The above method can yield optical waveguide structures with excellent optical performance, good light transmittance, and a thin, lightweight design. The fabrication process is simple and easy to implement, which helps reduce the difficulty of molding high-performance, thin-and-light optical waveguide structures, decreases processing costs, and facilitates industrial processing.

[0179] In the example where the optical waveguide structure includes a cover plate, after step S103 above, the method may further include:

[0180] Step S104: Provide a cover plate.

[0181] Step S105: Cover the side of the optical waveguide substrate with the groove with the cover plate to seal the cover plate to the optical waveguide substrate.

[0182] The structure of the cover plate, the assembly relationship between the cover plate and the optical waveguide substrate, and the sealing connection method can be found above, and will not be repeated here.

[0183] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal connection of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances. The terms "first," "second," "third," "fourth," etc. (if present) are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0184] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them; although the embodiments of this application have been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An optical waveguide structure (10), characterized in that, include: An optical waveguide substrate (11) has a groove (111) on at least one side; Imprinting adhesive (120) is located in the groove (111) and forms a grating structure (12), which includes a plurality of spaced fences (121). A protective layer (13) is disposed in the groove (111), a portion of the protective layer (13) covers the grating structure (12), and a portion of the protective layer (13) fills the space between adjacent gratings (121).

2. The optical waveguide structure (10) according to claim 1, characterized in that, The protective layer (13) has a side facing away from the grating structure (12) that is flush with the side of the optical waveguide substrate (11) that has the groove (111).

3. The optical waveguide structure (10) according to claim 1, characterized in that, The protective layer (13) includes a high-hardness adhesive layer.

4. The optical waveguide structure (10) according to claim 3, characterized in that, The pencil hardness of the protective layer (13) is greater than or equal to 5H.

5. The optical waveguide structure (10) according to claim 1, characterized in that, The difference between the refractive index of the grating structure (12) and the refractive index of the protective layer (13) is greater than or equal to 0.

1.

6. The optical waveguide structure (10) according to any one of claims 1-5, characterized in that, The thickness of the portion of the optical waveguide substrate (11) corresponding to the groove (111) is greater than or equal to 0.1 mm.

7. The optical waveguide structure (10) according to any one of claims 1-5, characterized in that, The ratio of the depth of the groove (111) to the thickness of the optical waveguide substrate (11) is less than or equal to 50%.

8. The optical waveguide structure (10) according to claim 7, characterized in that, The depth of the groove (111) ranges from 1 μm to 0.7 mm.

9. The optical waveguide structure (10) according to any one of claims 1-5, characterized in that, The refractive index range of the grating structure (12) is 1.6 to 2.

5.

10. The optical waveguide structure (10) according to claim 9, characterized in that, The refractive index of the grating structure (12) is greater than or equal to 1.

9.

11. The optical waveguide structure (10) according to any one of claims 1-5, characterized in that, The number of grating structures (12) is multiple; The optical waveguide substrate (11) has a plurality of grooves (111) on one side, and a plurality of grating structures (12) are respectively disposed in the plurality of grooves (111).

12. The optical waveguide structure (10) according to any one of claims 1-5, characterized in that, The number of grating structures (12) is multiple; The optical waveguide substrate (11) has grooves (111) on both opposite sides, and a plurality of grating structures (12) are respectively disposed in the plurality of grooves (111).

13. The optical waveguide structure (10) according to claim 12, characterized in that, The grating structure (12) includes an insertion structure (12a), an output structure, and a relay structure. The insertion structure (12a) is used to couple light into the optical waveguide substrate (11) for transmission. The relay structure is used to transmit the light to the output structure. The output structure is used to couple the light out to the outside of the optical waveguide structure (10). The coupling structure (12a) and the relay structure are disposed on the same surface of the optical waveguide substrate (11), and the coupling structure is disposed on the other surface of the optical waveguide substrate (11).

14. The optical waveguide structure (10) according to any one of claims 1-5, characterized in that, It also includes a cover plate (14) that covers the side of the optical waveguide substrate (11) having the groove (111) and is sealed to the optical waveguide substrate (11).

15. A display device (100), characterized in that, Includes a display module (103) and an optical waveguide structure (10) as described in any one of claims 1-14, wherein the light emitted by the display module (103) is transmitted through the optical waveguide structure (10).

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