Display device and head-mounted display equipment

Abstract

The invention relates to a display device and head-mounted display equipment. The display device comprises a first optical waveguide assembly, a reflection element and an adhesion structure. The reflecting element is arranged on the surface of the first optical waveguide assembly. And the adhesion structure is arranged on one side, opposite to the first optical waveguide assembly, of the reflecting element, so that the first optical waveguide assembly can be adhered to other elements. According to the display device, miniaturization and good optical performance can be achieved at the same time.

Description

Technical Field

[0001] The present application relates to the technical field of head-mounted display devices, and particularly to a display device and a head-mounted display device. Background Art

[0002] Head-mounted display devices such as virtual reality (VR) devices, augmented reality (AR) devices, and mixed reality (MR) devices usually have a diffractive optical waveguide module to conduct the light emitted by the light engine to the user's eyes. Compared with other methods such as geometric optical waveguides and free-form surface modules, using a diffractive optical waveguide can effectively reduce the size and weight of the head-mounted display device. However, with the improvement of user requirements, the size of the head-mounted display device still needs to be further compressed, and the current head-mounted display device is difficult to balance miniaturization and good optical performance. Summary of the Invention

[0003] Embodiments of the present application provide a display device and a head-mounted display device to solve the problem that the current head-mounted display device is difficult to balance miniaturization and good optical performance.

[0004] A display device includes:

[0005] A first optical waveguide component;

[0006] A reflection element disposed on the surface of the first optical waveguide component; and,

[0007] An adhesion structure disposed on the side of the reflection element facing away from the first optical waveguide component for adhesively connecting the first optical waveguide component to other components.

[0008] A head-mounted display device includes the display device according to any one of the above embodiments.

[0009] In the above display device, the adhesion structure is disposed on the first optical waveguide component for adhesively connecting the first optical waveguide component to other components such as the light engine or the frame, rather than adhesively connecting to other components through a cover plate disposed on one side of the first optical waveguide component, which is beneficial to saving the setting of the cover plate, thereby facilitating the compression of the size of the display device. Moreover, a reflection element is disposed between the adhesion structure and the first optical waveguide component, and the reflection surface of the reflection element can reflect the light incident on the reflection element in the first optical waveguide component back to the first optical waveguide component, avoiding the light from emitting from the adhesion structure or being absorbed by the adhesion structure, so as to improve the light utilization efficiency of the first optical waveguide component while reducing the size of the display device, and improve the optical performance such as the brightness uniformity and color uniformity of the display device, and further enable the display device to balance miniaturization and good optical performance. Description of the Drawings

[0010] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0011] Figure 1 It is a schematic diagram of the optical path of light emitted from the interface between the optical waveguide and the glue in a traditional display device.

[0012] Figure 2 It is a schematic diagram of the structure of a display device in some embodiments.

[0013] Figure 3 It is a schematic diagram of the structure of a head-mounted display device in some embodiments.

[0014] Figure 4 For Figure 2 It is a schematic diagram of the structure of some components of the display device shown.

[0015] Figure 5 It is a schematic diagram of the structure of a display device in some other embodiments.

[0016] Figure 6 For Figure 5 It is a schematic diagram of the structure of some components of the display device shown.

[0017] Figure 7 It is a schematic diagram of the structure of a reflective element with a protective film in some embodiments.

[0018] Figure 8 It is a schematic diagram of the process of arranging a reflective element on a first optical waveguide component in some embodiments.

[0019] Reference numerals in the drawings:

[0020] 1. Optical waveguide; 2. Glue;

[0021] 10. Display device; 11. Optical engine; 111. Sleeve; 112. Light-emitting part; 12. First optical waveguide component; 121. First waveguide sheet; 122. First surface; 123. Second surface; 124. First coupling grating; 125. First output grating; 13. Frame; 14. Reflective element; 15. Adhesion structure; 16. Cover plate; 17. Second optical waveguide component; 171. Second waveguide sheet; 172. Second coupling grating; 173. Second output grating; 18. Bracket; 19. Protective film; 191. Glue; 20. Head-mounted display device; 21. Eyeglass frame; 30. Coating fixture; 31. Coating tank. Detailed implementation manners

[0022] To facilitate the understanding of the present application, the present application will be described more comprehensively below with reference to the relevant accompanying drawings. Preferred embodiments of the present application are shown in the accompanying drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0023] In the display device of a traditional head-mounted display device, an optical waveguide is usually provided to conduct the light emitted by the optical engine. When the light is conducted in the optical waveguide, if the light hits the interface between the optical waveguide and the air, since the refractive index of the material of the optical waveguide itself is much greater than that of the air, the light is likely to reach the total reflection critical angle at the interface between the optical waveguide and the air and undergo total reflection, thus having a high light transmission efficiency. In a traditional display device, protective cover plates are usually provided on two opposite sides of the optical waveguide. The optical engine is glued to the protective cover plates, and both protective cover plates on both sides are spaced from the optical waveguide, which can not only provide protection for the optical waveguide but also ensure that both sides of the optical waveguide are air media, thereby increasing the total reflection probability of the light at the interface between the optical waveguide and the air and improving the light transmission efficiency of the optical waveguide. However, the setting of the protective cover plates on both sides of the optical waveguide will increase the size of the display device, which is not conducive to the miniaturization of the head-mounted display device.

[0024] Referring to Figure 1 as shown, if one of the protective cover plates of the optical waveguide 1 is omitted in order to compress the size of the display device, the optical engine is directly adhered to the optical waveguide 1 through the glue 2. Since the refractive index of the glue 2 is usually greater than that of the air, the total reflection critical angle of the light at the interface between the optical waveguide 1 and the glue 2 is greater than the total reflection critical angle of the light at the interface between the optical waveguide 1 and the air, which easily leads to a decrease in the total reflection probability of the light at the interface between the optical waveguide 1 and the glue 2, and part of the light is likely to refract and transmit through the glue 2. When the glue 2 is a black glue 2, the glue 2 may also absorb the light hitting the interface between the glue 2 and the optical waveguide 1, resulting in a decrease in the light transmission efficiency of the optical waveguide 1 and a decrease in the color uniformity and brightness uniformity of the display device. Thus, it is difficult for a traditional display device to balance miniaturization and good optical performance.

[0025] To solve the above problems, the present application provides a display device and a head-mounted display device.

[0026] Please refer to Figure 2 、 Figure 3 and Figure 4 , Figure 2 which are schematic structural diagrams of the display device 10 in some embodiments, Figure 3 and Figure 4Schematic diagram of the structure of some components of the display device 10 in some embodiments. The head-mounted display device 20 provided in the present application includes, but is not limited to, VR devices, AR devices, MR devices, etc. The head-mounted display device 20 may include a frame 21 and a display device 10. The display device 10 has a frame 13. The frame 21 is connected to the frame 13 and can wear the frame 13 on the user's head. The display device 10 can display images for the user to view. In some embodiments, the display device 10 includes an optical engine 11 and a first optical waveguide assembly 12. The optical engine 11 can emit light. The light emitted by the first optical engine 11 can be coupled into the first optical waveguide assembly 12 and then coupled out to the user's eyes after being conducted by the first optical waveguide assembly 12. The frame 13 can be used as a support member of the display device 10 to provide structural support and protection for the first optical waveguide assembly 12 and the optical engine 11.

[0027] Combined with Figure 2 and Figure 4 As shown, in some embodiments, the display device 10 further includes a reflection element 14 and an adhesion structure 15. The reflection element 14 is provided on the surface of the first optical waveguide assembly 12. The surface of the reflection element 14 facing the first optical waveguide assembly 12 is a reflection surface. The adhesion structure 15 is provided on the side of the reflection element 14 facing away from the first optical waveguide assembly 12 for the first optical waveguide assembly 12 to adhere to other components. For example, the optical engine 11 of the display device 10 can be adhered to the first optical waveguide assembly 12 through the adhesion structure 15.

[0028] For the above display device 10, the adhesion structure 15 is provided on the first optical waveguide assembly 12 for the first optical waveguide assembly 12 to adhere to other components such as the optical engine 11, which is beneficial to reducing the size of the display device 10. Moreover, a reflection element 14 is provided between the adhesion structure 15 and the first optical waveguide assembly 12. The reflection surface of the reflection element 14 can reflect the light incident on the reflection element 14 in the first optical waveguide assembly 12 back to the first optical waveguide assembly 12, avoiding the light from emitting from or being absorbed by the adhesion structure 15. Thus, while reducing the size of the display device 10, the light utilization efficiency of the first optical waveguide assembly 12 can be improved, and the optical performance such as the brightness uniformity and color uniformity of the display device 10 can be enhanced. Furthermore, the display device 10 can achieve both miniaturization and good optical performance.

[0029] In some embodiments, the first optical waveguide assembly 12 includes a first waveguide sheet 121, a first coupling grating 124, and a first output grating 125. The first waveguide sheet 121 has a first surface 122 and a second surface 123 disposed opposite to each other. The first coupling grating 124 and the first output grating 125 are spaced apart on the first surface 122, and the reflecting element 14 is disposed on the second surface 123. The light emitted by the optical engine 11 can enter the first waveguide sheet 121 from the first coupling grating 124 and be conducted in the first waveguide sheet 121 to the first output grating 125, so as to be emitted from the first output grating 125 out of the first optical waveguide assembly 12 for the user to view. It can be understood that the adhesion structure 15 can be adhered to the optical engine 11 or the frame 13 on the side of the reflecting element 14 facing away from the first waveguide sheet 121, so that the display device 10 does not need to be provided with a cover plate 16 on the second surface 123 side of the first waveguide sheet 121 to adhere to the optical engine 11 or the frame 13, thereby omitting the cover plate 16 on the side where the second surface 123 of the first waveguide sheet 121 is located, which is beneficial to reducing the size of the display device 10.

[0030] In some embodiments, the display device 10 may further include a cover plate 16 disposed on the side where the first surface 122 of the first waveguide sheet 121 is located. The cover plate 16 is spaced apart from the first optical waveguide assembly 12, and the air medium is between the cover plate 16 and the first optical waveguide assembly 12. Thus, while the display device 10 saves the cover plate 16 on the side where the second surface 123 of the first waveguide sheet 121 is located to compress the size of the display device 10, the cover plate 16 on the first surface 122 side of the first waveguide sheet 121 can encapsulate the side of the first waveguide sheet 121 where the first coupling grating 124 and the first output grating 125 are provided, so as to provide a protection effect on the first coupling grating 124 and the first output grating 125. Moreover, the setting of the air medium between the cover plate 16 and the first optical waveguide assembly 12 can also increase the total reflection probability of the light in the first waveguide sheet 121 on the first surface 122, thereby improving the light utilization efficiency and optical performance of the display device 10. Thus, the above display device 10 can effectively balance miniaturization, good imaging quality, and good structural reliability.

[0031] Combined with Figure 2 and Figure 4As shown, in some embodiments, the first optical waveguide component 12 is a reflective diffraction optical waveguide, the first coupling grating 124 and the first output coupling grating 125 are both reflective diffraction gratings. The optical engine 11 is disposed on the side where the second surface 123 of the first waveguide sheet 121 is located. The optical engine 11 includes a sleeve 111 and a light emitting portion 112 disposed within the sleeve 111. The sleeve 111 of the optical engine 11 is adhered to the first optical waveguide component 12 through an adhesion structure 15. In this embodiment, the light emitted by the light emitting portion 112 of the optical engine 11 passes through the first waveguide sheet 121 and hits the first coupling grating 124, and is coupled into the first waveguide sheet 121 by the first coupling grating 124, and is conducted in the first waveguide sheet 121 in a reflective form to the first output coupling grating 125, and then is coupled out of the first waveguide sheet 121 by the first output coupling grating 125.

[0032] Reference Figure 4 As shown, it can be understood that in this embodiment, when the light is coupled into the first waveguide sheet 121 by the first coupling grating 124, if the light hits the portion of the second surface 123 outside the reflecting element 14, that is, hits the interface between the first waveguide sheet 121 and the air medium, since the refractive index of the first waveguide sheet 121 is much higher than that of the air medium, for example, the refractive index of air can be 1, and the refractive index of the first waveguide sheet 121 can be 1.6 - 2.0, the light is likely to undergo total internal reflection at the interface between the first waveguide sheet 121 and the air medium, and the light transmission efficiency is high. When the light hits the interface between the first waveguide sheet 121 and the reflecting element 14, although the refractive index of the adhesion structure 15 is higher than that of air, for example, the refractive index of the adhesion structure 15 can be 1.5, the light is not likely to undergo total internal reflection at the interface between the adhesion structure 15 and the first waveguide sheet 121, but due to the arrangement of the reflecting element 14, the reflecting surface of the reflecting element 14 can reflect the light back into the first waveguide sheet 121, preventing the light from refracting out of the adhesion structure 15 or being absorbed by the adhesion structure 15. Thus, while the first optical waveguide component 12 is adhered to the optical engine 11 through the adhesion structure 15 to save the cover plate 16 on the side where the second surface 123 of the first waveguide sheet 121 is located, the light transmission efficiency can be effectively improved, enabling the display device 10 to maintain good optical performance.

[0033] In some embodiments, the projection of the portion of the sleeve 111 of the optical engine 11 adhered to the first optical waveguide assembly 12 on the first surface 122 surrounds the first coupling grating 124, and the projection of the reflecting element 14 on the first surface 122 surrounds at least part of the contour of the first coupling grating 124. In some embodiments, the projection of the reflecting element 14 on the first surface 122 is offset from the first coupling grating 124. For example, the projection of the reflecting element 14 on the first surface 122 extends around at least part of the contour of the first coupling grating 124 and does not overlap with the first coupling grating 124. Thus, while the reflecting element 14 is provided to improve the light transmission efficiency, it can also prevent the reflecting element 14 from blocking the light emitted by the optical engine 11 from reaching the first coupling grating 124, which is also beneficial to improving the light utilization efficiency of the display device 10.

[0034] It can be understood that although the reflection effect of the reflecting surface of the reflecting element 14 on light is higher than that of the interface between the first waveguide sheet 121 and the adhesion structure 15 when the first waveguide sheet 121 is in direct contact with the adhesion structure 15, the reflection effect of the reflecting element 14 on light is still lower than total reflection. Therefore, while ensuring that the reflecting element 14 can effectively separate the first waveguide sheet 121 and the adhesion structure 15, the coverage area of the reflecting element 14 on the second surface 123 should be as small as possible, so that more light incident on the second surface 123 reaches the interface between the first waveguide sheet 121 and the air medium and is transmitted in the form of total reflection, thereby maximizing the light transmission efficiency. Based on this, in some embodiments, the width of the reflecting element 14 is greater than or equal to 1 mm and less than or equal to 3 mm. The reflecting element 14 is arranged around at least part of the contour of the first coupling grating 124, and the projection of the reflecting element 14 on the first surface 122 can be generally annular or a part of an annulus. The width of the reflecting element 14 can be understood as the dimension of the reflecting element 14 in the radial direction of the annulus. Thus, it can not only ensure that the reflecting element 14 has a sufficient coverage area for the adhesion structure 15 to be arranged, so as to improve the bonding strength between the optical engine 11 or other components and the first optical waveguide assembly 12 and enhance the structural stability of the display device 10, but also ensure that the coverage area of the reflecting element 14 is not too large, which is beneficial to improving the light transmission efficiency of the first optical waveguide assembly 12.

[0035] In this embodiment, the reflecting element 14 can be arranged around the first coupling grating 124 to be generally annular, and the projection of the part where the sleeve 111 is adhered to the first optical waveguide assembly 12 on the second surface 123 can be completely located within the reflecting element 14. Of course, after the light emitted by the optical engine 11 is coupled into the first waveguide sheet 121 by the first coupling grating 124, the light generally conducts from the position where the first coupling grating 124 is located to the side where the first coupling grating 125 is located, and less light hits the part of the second surface 123 that is away from the first coupling grating 125 and closer to the first coupling grating 124. Therefore, referring to Figure 2 As shown, in some embodiments, the reflecting element 14 can also be only arranged on the part of the second surface 123 that is closer to the first coupling grating 125 and away from the first coupling grating 124. At this time, the part of the structure for adhering the sleeve 111 to the first optical waveguide assembly 12 that is located on the reflecting element 14 can be regarded as the adhering structure 15 of the present application, and the part outside the reflecting element 14 is used to enhance the adhesion strength between the sleeve 111 and the first optical waveguide assembly 12.

[0036] Referring to Figure 2 As shown, in this embodiment, the frame 13 of the display device 10 can be adhered to the cover plate 16 on the side of the cover plate 16 facing away from the first optical waveguide assembly 12 by glue 191 to provide support and protection for components such as the first optical waveguide assembly 12, the cover plate 16, and the optical engine 11. Of course, more optical waveguide elements can also be provided in the display device 10. The refractive indices of different optical waveguide elements can be the same or different, and different optical waveguide elements can be used to transmit light of different bands to meet different light transmission requirements.

[0037] In some embodiments, the display device 10 further includes a second optical waveguide assembly 17. The second optical waveguide assembly 17 is arranged between the first optical waveguide assembly 12 and the cover plate 16 and includes a second waveguide sheet 171, a second coupling grating 172, and a second coupling grating 173. Both the second coupling grating 172 and the second coupling grating 173 are arranged on the side of the second waveguide sheet 171 facing away from the first optical waveguide assembly 12. The second optical waveguide assembly 17, the first optical waveguide assembly 12, and the cover plate 16 are all spaced apart so that both opposite surfaces of the second waveguide sheet 171 are in contact with the air medium, improving the total reflection probability of light in the second waveguide sheet 171, thereby improving the light transmission efficiency of the display device 10. In Figure 2In the illustrated embodiment, the second optical waveguide assembly 17 may also be a reflective diffraction optical waveguide, and both the second coupling grating 172 and the second output grating 173 are reflective diffraction gratings. The first optical waveguide assembly 12, the second optical waveguide assembly 17, and the cover plate 16 may be interconnected through a bracket 18. Part of the light rays emitted by the optical engine 11 can sequentially pass through the first waveguide sheet 121, the first coupling grating 124, and the second waveguide sheet 171 and reach the second coupling grating 172, and are coupled into the second waveguide sheet 171 by the second coupling grating 172, and are conducted in the second waveguide sheet 171 to the second output grating 173 by total internal reflection, and thus are coupled out of the second waveguide sheet 171 by the second output grating 173.

[0038] Of course, the display device 10 may further include a greater number of optical waveguide elements. Other optical waveguide elements may be disposed between the first optical waveguide assembly 12 and the cover plate 16 to meet more different light transmission requirements, which will not be elaborated herein.

[0039] Further, in some embodiments, when the optical engine 11 is adhered to the first optical waveguide assembly 12 through the adhesion structure 15 provided on the reflection element 14, the adhesion structure 15 may be a black glue 191. In traditional display devices, setting the black glue 191 easily absorbs light and reduces the light utilization efficiency. In this embodiment, since the reflection element 14 is provided to space the adhesion structure 15 from the first optical waveguide assembly 12, setting the adhesion structure 15 as the black glue 191 will not reduce the light transmission efficiency. The setting of the black glue 191 can absorb the light rays incident between the sleeve 111 and the first optical waveguide assembly 12, and avoid the leakage of the light rays emitted by the optical engine 11 in the gap between the sleeve 111 and the first optical waveguide assembly 12 to generate stray light, thereby facilitating the improvement of the imaging quality of the display device 10.

[0040] Please refer to Figure 5 and Figure 6 , in some other embodiments, the first optical waveguide assembly 12 may be a transmissive diffraction optical waveguide, and both the first coupling grating 124 and the first output grating 125 are transmissive diffraction gratings. The optical engine 11 is disposed on the side where the first surface 122 of the first waveguide sheet 121 is located, and the frame 13 is adhered to the first optical waveguide assembly 12 through the adhesion structure 15 on the side where the second surface 123 of the first waveguide sheet 121 is located. The light rays emitted by the optical engine 11 can reach the first coupling grating 124 and are coupled into the first waveguide sheet 121 by the first coupling grating 124, and are conducted in the first waveguide sheet 121 to the first output grating 125, and thus are coupled out of the first waveguide sheet 121 by the first output grating 125. Refer to Figure 6As shown, it can be understood that after the light is coupled into the first waveguide plate 121 by the first coupling grating 124, when the light hits the interface between the first waveguide plate 121 and the reflection element 14, although the refractive index of the adhesion structure 15 is higher than that of air and it is not easy for the light to undergo total internal reflection at the interface between the first waveguide plate 121 and the adhesion structure 15, due to the arrangement of the reflection element 14, the reflection surface of the reflection element 14 can reflect the light hitting the reflection element 14 back into the first waveguide plate 121, preventing the light from refracting out of the adhesion structure 15 or being absorbed by the adhesion structure 15. Thus, when the first optical waveguide assembly 12 is adhered to the spectacle frame 13 through the adhesion structure 15 to save the cover plate 16 on the side of the first waveguide plate 121 facing the spectacle frame 13, the light transmission efficiency can be effectively improved, enabling the display device 10 to maintain good optical performance.

[0041] In Figure 6 In the illustrated embodiment, the display device 10 may include a cover plate 16 disposed on the side where the first surface 122 of the first waveguide plate 121 is located. The cover plate 16 is spaced apart from the first optical waveguide assembly 12, and an air medium is formed between the cover plate 16 and the first optical waveguide assembly 12. The light engine 11 may be disposed on the side of the cover plate 16 facing away from the first optical waveguide assembly 12 and adhered to the cover plate 16. Thus, the cover plate 16 can encapsulate the first surface 122 of the first optical waveguide assembly 12, thereby providing a protective effect on the first coupling grating 124 and the second coupling grating 172, and also providing a structural support effect for the light engine 11. Moreover, the setting of the air medium between the cover plate 16 and the first optical waveguide assembly 12 can also increase the probability of total internal reflection of the light in the first waveguide plate 121 on the first surface 122, thereby improving the light utilization efficiency and optical performance of the display device 10. Thus, the above-mentioned display device 10 can effectively balance miniaturization, good imaging quality, and good structural reliability.

[0042] In this embodiment, the display device 10 may also include a second optical waveguide assembly 17. The second optical waveguide assembly 17 is disposed between the first optical waveguide assembly 12 and the cover plate 16 and includes a second waveguide plate 171, a second coupling grating 172, and a second output grating 173. The second coupling grating 172 and the second output grating 173 are disposed on the side of the second waveguide plate 171 facing the light engine 11. The second optical waveguide assembly 17 may be a transmissive diffraction optical waveguide, and both the second coupling grating 172 and the second output grating 173 are transmissive diffraction gratings. Part of the light emitted by the light engine 11 can hit the second coupling grating 172 and be coupled into the second waveguide plate 171 by the second coupling grating 172, and another part of the light emitted by the light engine 11 can sequentially pass through the second coupling grating 172 and the second waveguide plate 171 and hit the first coupling grating 124, and thus be coupled into the first waveguide plate 121 by the first coupling grating 124.

[0043] In Figure 6 the illustrated embodiment, the coverage area of the reflective element 14 on the second surface 123 is not limited, as long as the adhesion structure 15 has sufficient adhesion area to adhere the first optical waveguide assembly 12 and the spectacle frame 13, and can separate the adhesion structure 15 from the first waveguide sheet 121 to improve the light transmission efficiency of the first optical waveguide assembly 12. In some embodiments, the projection of the reflective element 14 on the first surface 122 at least covers the area where the first coupling grating 124 is located.

[0044] It should be noted that in the present application, when the display device 10 is provided with two or more optical waveguide elements, the optical waveguide element provided with the reflective element 14 is referred to as the first optical waveguide assembly 12, and the surface of the first optical waveguide assembly 12 where the reflective element 14 is provided is referred to as the second surface 123. In some embodiments, the adhesion structure 15 can be any applicable glue 191, and the reflective element 14 can be a coating layer provided on the second surface 123, such as a silver coating layer or an aluminum coating layer, etc., any applicable coating layer with a high reflectivity. The reflection efficiency of the reflective surface of the reflective element 14 for light includes but is not limited to 70%, 80%, 90% or higher, and can be specifically set according to the light transmission requirements.

[0045] When the reflective element 14 is a structure such as a silver coating layer or an aluminum coating layer that is easily corroded, referring to Figure 7 as shown, in some embodiments, the display device 10 further includes a protective film 19. The protective film 19 is disposed between the reflective element 14 and the adhesion structure 15, and covers at least part of the surface of the reflective element 14 facing away from the first optical waveguide assembly 12 to provide a protective effect on the reflective element 14, maintain the optical performance stability of the reflective element 14, and prevent the reflective element 14 from being corroded and resulting in a decrease in reflectivity. The protective film 19 includes but is not limited to a screen printing ink layer, or a dense film layer such as a silicon dioxide film layer or an aluminum oxide film layer, as long as it can provide a protective effect on the reflective element 14.

[0046] Combined with Figure 7 and Figure 8As shown, in some embodiments, a coating fixture 30 may be used to sequentially dispose a reflective element 14 and a protective film 19 on the first optical waveguide assembly 12. The coating fixture 30 may be provided with a coating tank 31, and the shape and size of the coating tank 31 may be adapted to the shape and size of the reflective element 14. When disposing the reflective element 14, the first optical waveguide assembly 12 or the wafer for fabricating the first optical waveguide assembly 12 is placed on the coating fixture 30, such that the position on the first optical waveguide assembly 12 for disposing the reflective element 14 is aligned with the coating tank 31, thereby disposing the reflective element 14 on the first optical waveguide assembly 12 through the coating tank 31. After the reflective element 14 is disposed, a protective film 19 layer is then disposed on the reflective element 14 through the coating tank 31. Using the coating fixture 30 can improve the setting accuracy and setting size of the reflective element 14, thereby improving the optical performance of the first optical waveguide assembly 12.

[0047] It can be understood that when the protective film 19 is a screen-printed ink layer, since ink overflow may occur during screen printing, to prevent the screen-printed ink from overflowing outside the reflective element 14 and contacting the first optical waveguide assembly 12, resulting in a reduction in the light transmission efficiency of the first optical waveguide assembly 12 due to the light absorption of the screen-printed ink, when setting the screen-printed ink, the screen-printed ink may be recessed 0.1 mm - 0.3 mm relative to the contour of the reflective element 14 to reserve an ink overflow space. When the protective film 19 is a dense film layer such as a silicon dioxide film layer or an aluminum oxide film layer, since the protective film 19 is not easily extended outside the reflective element 14 during setting, the protective film 19 may overlap with the reflective element 14 to cover the entire surface of the reflective element 14 facing away from the first optical waveguide assembly 12, improving the protective effect of the protective film 19 on the reflective element 14, thereby improving the optical performance stability of the reflective element 14.

[0048] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0049] The above-described embodiments only represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A display device, characterized in that, comprising: a first optical waveguide component; a reflection element disposed on the surface of the first optical waveguide component; and, an adhesion structure disposed on a side of the reflection element facing away from the first optical waveguide component for adhering the first optical waveguide component to other components.

2. The display device according to claim 1, characterized in that, the first optical waveguide component includes a first waveguide sheet and a first coupling grating. The first waveguide sheet has a first surface and a second surface disposed opposite to each other. The first coupling grating is disposed on the first surface, and the reflection element is disposed on the second surface.

3. The display device according to claim 2, characterized in that, the display device further includes an optical engine. The optical engine is disposed on a side where the second surface of the first waveguide sheet is located. The sleeve of the optical engine is adhered to the first optical waveguide component through the adhesion structure.

4. The display device according to claim 3, characterized in that, the projection of the reflection element on the first surface surrounds at least part of the contour of the first coupling grating. The width of the reflection element is greater than or equal to 1 mm and less than or equal to 3 mm.

5. The display device according to claim 3, characterized in that, the display device further includes a cover plate. The cover plate is disposed on a side where the first surface of the first waveguide sheet is located.

6. The display device according to claim 5, characterized in that, the display device further includes a second optical waveguide component. The second optical waveguide component is disposed between the first optical waveguide component and the cover plate and includes a second waveguide sheet and a second coupling grating. The second coupling grating is disposed on a side of the second waveguide sheet facing away from the first optical waveguide component.

7. The display device according to claim 3, characterized in that, the adhesion structure includes black glue.

8. The display device according to claim 2, characterized in that, the display device further includes a frame. At least part of the frame is disposed on a side where the second surface of the first waveguide sheet is located and is adhered to the first optical waveguide component through the adhesion structure.

9. The display device according to claim 8, characterized in that, the display device further includes an optical engine and a cover plate. The cover plate is disposed on a side where the first surface of the first waveguide sheet is located. The optical engine is disposed on a side of the cover plate facing away from the first optical waveguide component and is adhered to the cover plate.

10. The display device according to claim 9, characterized in that, the display device further includes a second optical waveguide component. The second optical waveguide component is disposed between the first optical waveguide component and the cover plate and includes a second waveguide sheet and a second coupling grating. The second coupling grating is disposed on a side of the second waveguide sheet facing the optical engine.

11. The display device according to claim 8, characterized in that, the projection of the reflection element on the first surface at least covers the area where the first coupling grating is located.

12. The display device according to claim 6 or 10, characterized in that, the first optical waveguide component, the second optical waveguide component, and the cover plate are sequentially spaced apart.

13. The display device according to any one of claims 1-11, characterized in that, the display device further includes a protective film, the protective film is disposed between the reflective element and the adhesion structure, and covers at least a part of the surface of the reflective element facing away from the first optical waveguide assembly.

14. A head-mounted display device, characterized in that, it includes the display device according to any one of claims 1-13.

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