Optical waveguide assembly and AR glasses
By utilizing a stacked waveguide structure with different refractive indices in the optical waveguide assembly, the ghosting problem is solved by preventing light from entering the coupling region before it has expanded, thus improving imaging quality and stability and reducing production costs.
Patent Information
- Application Number
- CN202520629942.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-03
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2035-04-03
AI Technical Summary
In existing technologies, some of the coupled light rays in a two-dimensional optical waveguide enter the coupled-out region directly without passing through the turning area, forming ghost images and affecting the imaging quality.
Design an optical waveguide assembly by setting coupling and deflection elements on a first waveguide plate and coupling out elements on a second waveguide plate. Utilizing the stacked structure of the first and second waveguide plates with different refractive indices, light is transmitted through total internal reflection in the first waveguide plate, avoiding direct entry into the second waveguide plate and ensuring that light does not enter the coupling out region before it expands.
It effectively avoids ghosting, improves the imaging quality of optical waveguide components, reduces production costs and process difficulty, and enhances the stability and imaging uniformity of optical waveguide components.
Smart Images
Figure CN223955836U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to optical element technical field especially is related to a light wave guide subassembly and AR glasses. BACKGROUND
[0002] Augmented Reality (AR) is the technology that the information provided by the computer system increases the user's perception to the real world, and the virtual object, scene or system prompt information generated by the computer is superimposed to the real scene, thereby realizing the enhancement to the reality. The AR glasses based on light wave guide are the mainstream scheme at present, and the light wave guide structure is small, light in weight and powerful in optical function, is the core device for realizing the light AR glasses.
[0003] Among them, the two-dimensional light wave guide exit pupil can be expanded in two directions, and better imaging effect can be realized by using more compact volume, however, in the two-dimensional wave guide, part of the coupling-in light can enter the coupling-out area without passing through the light turning part, and this part of light will form a ghost image, thereby affecting the imaging quality of the light wave guide. UTILITARY MODEL CONTENT
[0004] The utility model aims at solving one of the technical problems in the prior art. For this purpose, the utility model provides a light wave guide subassembly, which can avoid the coupling-in light directly shooting at the coupling-out area without passing through the turning area, thereby avoiding the formation of ghost image and improving the imaging quality of the light wave guide subassembly.
[0005] The utility model further provides AR glasses with the light wave guide subassembly.
[0006] According to the light wave guide subassembly of the utility model, the light wave guide subassembly comprises:
[0007] Optical machine, the optical machine is used for emitting light;
[0008] First wave guide plate, the first wave guide plate is provided with the coupling-in element and the turning element, and the refractive index of the first wave guide plate is n1;
[0009] Second wave guide plate, the second wave guide plate is stacked with the first wave guide plate, and the second wave guide plate is provided with the coupling-out element, and the refractive index of the second wave guide plate is n2;
[0010] The light emitted by the light engine enters the first waveguide plate through the coupling-in element and is totally reflected in the first waveguide plate and transmitted to the turning element. The turning element expands the light in a first direction to form expanded light and directs the expanded light to the second waveguide plate, so that the expanded light is totally reflected between the first waveguide plate and the second waveguide plate. The expanded light is transmitted through the first waveguide plate and the second waveguide plate and is directed to the coupling-out element. The coupling-out element expands the expanded light in a second direction and couples out the expanded light to form an image. The first direction and the second direction have an included angle, and n1>n2.
[0011] In some embodiments, the refractive index n1 of the first waveguide plate and the refractive index n2 of the second waveguide plate satisfy:
[0012] 2*arcsin[sin(1 / 2*F) / n1]<90°-arcsin(n2 / n1);
[0013] 2*arcsin[sin(1 / 2*F) / n1]<arcsin(n2 / n1)-arcsin(1 / n1);
[0014] 2*arcsin[sin(1 / 2*F) / n2]<90°-arcsin(1 / n2);
[0015] Wherein, F is the diagonal field of view angle of the light waveguide assembly.
[0016] In some optional embodiments, the first waveguide plate is a silicon carbide plate, and the second waveguide plate is a glass plate.
[0017] In some optional embodiments, the coupling-in element and the turning element are gratings, and the coupling-out element is an array of beam splitters.
[0018] In some optional embodiments, the coupling-in element is a reflective grating, the first waveguide plate includes opposite first and second surfaces, the reflective grating is disposed on the first surface, the second waveguide plate is disposed on the second surface, and the light engine is disposed on a side of the second waveguide plate away from the first waveguide plate.
[0019] In some optional embodiments, the array of beam splitters includes a plurality of beam splitters, and the reflectivity of the plurality of beam splitters gradually increases in the direction of light propagation.
[0020] In some embodiments, the first waveguide plate and the second waveguide plate are formed integrally by a bonding process.
[0021] In some embodiments, an anti-reflection film is arranged between the first waveguide plate and the second waveguide plate.
[0022] In some embodiments, a semi-reflective semi-transmissive film is arranged between the first waveguide plate and the second waveguide plate.
[0023] According to the optical waveguide assembly of the present application, the coupling-in element and the turning element are arranged on the first waveguide plate, the coupling-out element is arranged on the second waveguide plate, the first waveguide plate and the second waveguide plate are arranged in a stack, and the refractive index n1 of the first waveguide plate is greater than the refractive index n2 of the second waveguide plate. Therefore, the light rays coupled into the first waveguide plate through the coupling-in element can only be totally reflected and transmitted in the first waveguide plate, and after the light rays are expanded by the turning element, the expanded light rays can be totally reflected and transmitted between the first waveguide plate and the second waveguide plate. Thus, the coupling-in light rays will not enter the second waveguide plate and will not be coupled out from the coupling-out element before being expanded by the turning element, so that the generation of ghost image light rays is avoided, and the imaging quality of the optical waveguide assembly is improved.
[0024] According to the AR glasses of the second aspect of the present application, the optical waveguide assembly of the first aspect of the present application is arranged, so that the overall performance of the AR glasses is improved.
[0025] According to the AR glasses of the present application, the optical waveguide assembly of the first aspect is arranged, so that the overall performance of the AR glasses is improved.
[0026] The additional aspects and advantages of the present application will be partially given in the following description, partially will become obvious from the following description, or will be understood by the practice of the present application. BRIEF DESCRIPTION OF DRAWINGS
[0027] Figure 1 is a schematic diagram of a two-dimensional optical waveguide in the prior art;
[0028] Figure 2 is a schematic diagram of an optical waveguide assembly according to one embodiment of the present application;
[0029] Figure 3 is a side view of an optical waveguide assembly according to one embodiment of the present application;
[0030] Figure 4 is a side view of an optical waveguide assembly according to another embodiment of the present application;
[0031] Figure 5 is a side view of an optical waveguide assembly according to yet another embodiment of the present application;
[0032] Figure 6 is a side view of an optical waveguide assembly according to still another embodiment of the present application;
[0033] Figure 7 is a side view of the optical waveguide assembly according to another embodiment of the present application.
[0034] Reference signs:
[0035] 100: optical waveguide assembly; 10: light engine; 20: first waveguide plate; 21: coupling-in element; 22: turning element; 30: second waveguide plate; 31: coupling-out element; 311: beam splitter; 40: anti-reflection coating; 50: half mirror; 60: adjusting plate. DETAILED DESCRIPTION
[0036] Embodiments of the present application will be described in detail below, examples of which are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present application, and cannot be understood as limiting the present application.
[0037] The following disclosure provides many different embodiments, or examples, for implementing different structures of the present application. For the purpose of simplicity, the elements and arrangements of the examples described below are shown in the drawings as being in a specific arrangement. It is to be understood that this is merely an example and is not intended to limit the present application. Moreover, the present application can be implemented with other elements in addition to or in place of those shown. Additionally, the present application can be implemented in a different embodiment and of the examples described below. Such variations are not to be regarded as a departure from the spirit and scope of the present application. Furthermore, the present application provides examples of various specific processes and materials, but one of ordinary skill in the art can realize the applicability of other processes and / or the use of other materials.
[0038] The following description refers to the accompanying drawings. Figures 2-7 The optical waveguide assembly 100 according to an embodiment of the present application is described below, which comprises a light engine 10, a first waveguide plate 20 and a second waveguide plate 30, wherein the light engine 10 is used to emit light, and the light engine 10 can be one of a DLP light engine, a MicroLED light engine and an LCOS light engine.
[0039] As shown in Figures 2-3 , the first waveguide plate 20 is provided with a coupling-in element 21 and a turning element 22, and the refractive index of the first waveguide plate 20 is n1;
[0040] The second waveguide plate 30 is stacked with the first waveguide plate 20, and the second waveguide plate 30 is provided with a coupling-out element 31, and the refractive index of the second waveguide plate 30 is n2;
[0041] Please continue to refer to Figures 2-3It should be noted that the stacking of the first waveguide plate 20 and the second waveguide plate 30 means that the first waveguide plate 20 and the second waveguide plate 30 are stacked, and there is no air gap between the first waveguide plate 20 and the second waveguide plate 30.
[0042] Please continue to refer to Figures 2-3 Furthermore, the light emitted by the optomechanical system 10 enters the first waveguide plate 20 via the coupling element 21, and is transmitted by total internal reflection within the first waveguide plate 20 towards the deflection element 22. The deflection element 22 deflects the light in a first direction (e.g., Figure 2 The extended ray is formed in the X direction (as shown) and directed towards the second waveguide plate 30, so that the extended ray is transmitted by total internal reflection between the first waveguide plate 20 and the second waveguide plate 30. After being transmitted by total internal reflection between the first waveguide plate 20 and the second waveguide plate 30, the extended ray is directed towards the coupling element 31. The coupling element 31 adjusts the extended ray in the second direction (as shown) to form an extended ray. Figure 2 The image is extended along the Y direction (as shown) and the extended rays are coupled out to form an image, wherein the first direction and the second direction have an angle, and n1>n2.
[0043] Please continue to refer to Figures 2-3 Understandably, the light emitted by the optomechanical system 10 is coupled into the first waveguide plate 20 by the coupling element 21, where it undergoes total internal reflection. Since the first waveguide plate 20 and the second waveguide plate 30 are stacked, the total internal reflection angle of the light coupled into the first waveguide plate 20 must satisfy: n2 / n1 < sinA < 1, where A is the total internal reflection angle of the light coupled into the first waveguide plate 20 and undergoing total internal reflection. At this point, the light undergoes total internal reflection only within the first waveguide plate 20.
[0044] Furthermore, when the light rays transmitted by total internal reflection in the first waveguide plate 20 reach the deflection element 22, the deflection element 22 expands the light rays in the first direction to form extended light rays, and directs the extended light rays toward the second waveguide plate 30. It should be noted that, when the extended light rays travel from the first waveguide plate 20 to the second waveguide plate 30, in order to avoid total internal reflection at the interface between the first waveguide plate 20 and the second waveguide plate 30, the angle of incidence of the extended light rays traveling from the first waveguide plate 20 to the second waveguide plate 30 must satisfy: 1 / n 1 < sinB < n2 / n1, where B is the incident angle of the extended light ray when it travels from the first waveguide plate 20 to the second waveguide plate 30. At this time, when the extended light ray travels from the first waveguide plate 20 to the second waveguide plate 30, the light ray will not undergo total internal reflection at the interface between the first waveguide plate 20 and the second waveguide plate 30. And when the light ray travels from the second waveguide plate 30 to the first waveguide plate 20 again, the extended light ray will undergo total internal reflection at the interface between the first waveguide plate 20 and the air and travel to the second waveguide plate 30 again.
[0045] Furthermore, when the extended light ray enters the second waveguide plate 30 and strikes its surface, since the extended light ray needs to undergo total internal reflection between the first waveguide plate 20 and the second waveguide plate 30, the exit angle of the extended light ray striking the surface of the second waveguide plate 30 must satisfy: 1 / n2 < sinC < 1, where C is the exit angle of the extended light ray from the first waveguide plate 20 to the second waveguide plate 30, that is, the incident angle of the extended light ray striking the second waveguide plate 30. And, according to the law of refraction, n1sinB = n2sinC.
[0046] At this time, when the extended light beam is incident on the interface between the second waveguide plate 30 and the air, the extended light beam satisfies the total internal reflection condition, undergoes total internal reflection at the interface between the second waveguide plate 30 and the air, and is incident on the first waveguide plate 20. After refraction at the interface between the second waveguide plate 30 and the first waveguide plate 20, it is incident on the interface between the first waveguide plate 20 and the air, undergoes total internal reflection again at the interface between the first waveguide plate 20 and the air, and is incident on the second waveguide plate 30, thereby realizing the total internal reflection transmission of the extended light beam between the first waveguide plate 20 and the second waveguide plate 30.
[0047] The angle between the first direction and the second direction can be 90°. Of course, this embodiment of the present invention does not limit this, and the angle between the first direction and the second direction can also be 30°, 45°, 60°, 75°, etc.
[0048] The inventors discovered in their actual research that conventional two-dimensional optical waveguides, such as Figure 1 As shown, since the light rays entering the optical waveguide through the coupling region have a certain divergence angle, some of the coupled light rays may enter the coupling region without passing through the light turning part. This part of the light rays will form ghost images in the optical waveguide, ultimately affecting the imaging quality of the optical waveguide.
[0049] In view of this, the optical waveguide assembly 100 according to the present invention, by setting the coupling element 21 and the deflection element 22 on the first waveguide plate 20 and setting the coupling element 31 on the second waveguide plate 30, with the first waveguide plate 20 and the second waveguide plate 30 stacked, and making the refractive index n1 of the first waveguide plate 20 greater than the refractive index n2 of the second waveguide plate 30, can ensure that the light coupled into the first waveguide plate 20 through the coupling element 21 is transmitted by total internal reflection only in the first waveguide plate 20, and after being extended by the deflection element 22, the extended light can be transmitted by total internal reflection between the first waveguide plate 20 and the second waveguide plate 30. This ensures that the coupled light will not enter the second waveguide plate 30 before being extended by the deflection element 22, and will not be coupled out from the coupling element 31, thereby avoiding the generation of ghost light and improving the imaging quality of the optical waveguide assembly 100.
[0050] Please continue to refer toFigures 2-3 In some embodiments, the refractive index n1 of the first waveguide plate 20 and the refractive index n2 of the second waveguide plate 30 satisfy:
[0051] 2*arcsin[sin(1 / 2*F) / n1]<90°-arcsin(n2 / n1);
[0052] 2*arcsin[sin(1 / 2*F) / n1]<arcsin(n2 / n1)-arcsin(1 / n1);
[0053] 2*arcsin[sin(1 / 2*F) / n2]<90°-arcsin(1 / n2);
[0054] Wherein, F is the diagonal field of view angle of the optical waveguide assembly 100.
[0055] It should be noted that the above sinA and sinB corresponding inequalities can be obtained simultaneously 1 / n1<sinB<n2 / n1<sinA<1, further, arcsin(1 / n1)<B<arcsin(n2 / n1)<A<90° can be obtained, and from the sinC related inequality, arcsin(1 / n2)<C<90° can be obtained. Wherein, the above angle A and angle B are the incidence angles of the internal total reflection transmission when the light rays emitted by the light machine 10 are vertically incident to the first waveguide plate 20, and the angle C is the total reflection incidence angle in the second waveguide plate 30. In actual application, the image light projected by the light machine 10 is usually centered on the light ray of the center pixel of the picture vertically to the waveguide sheet, and has a certain angle expansion, that is, the coupling-in light ray angle is a range of 0°±1 / 2*F, wherein the angle F is the diagonal field of view angle of the optical waveguide assembly 100. According to the refraction law, the light ray angle range in the first waveguide plate 20 and the second waveguide plate 30 of the two kinds of refractive index materials is 0°±arcsin[sin(1 / 2*F) / n1] and 0°±arcsin[sin(1 / 2*F) / n2] respectively. In order to ensure that the optical waveguide assembly 100 can bear such a field of view angle, the value range of the angles A and B must be able to accommodate the above light ray range, and therefore, the refractive index n1 of the first waveguide plate 20 and the refractive index n2 of the second waveguide plate 30 satisfy:
[0056] 2*arcsin[sin(1 / 2*F) / n1]<90°-arcsin(n2 / n1);
[0057] 2*arcsin[sin(1 / 2*F) / n1]<arcsin(n2 / n1)-arcsin(1 / n1);
[0058] 2*arcsin[sin(1 / 2*F) / n2]<90°-arcsin(1 / n2);
[0059] Therefore, by setting the first waveguide plate 20 and the second waveguide plate 30 in the above refractive index range, on the one hand, the generation of ghost image light can be avoided, and by controlling the refractive index of the first waveguide plate 20 and the second waveguide plate 30 in the above range, the field of view of the image can be ensured, and the imaging quality of the optical waveguide assembly 100 can be improved; on the other hand, the strength of the optical waveguide assembly 100 can be improved, and the breakage of the optical waveguide assembly 100 caused by impact or falling can be avoided, and the stability of the optical waveguide assembly 100 is further improved.
[0060] Please continue to refer to Figures 2-3 In some optional embodiments, the first waveguide plate 20 is a silicon carbide plate, and the second waveguide plate 30 is a glass plate. It should be noted that the refractive index of silicon carbide is about 2.6, and the refractive index of ordinary glass is about 1.62. At this time, the optical waveguide assembly 100 has a larger field of view; and the silicon carbide has stable chemical properties, high thermal conductivity, small thermal expansion coefficient, good wear resistance and high hardness, thereby further improving the strength of the optical waveguide assembly 100, avoiding the breakage of the optical waveguide assembly 100 caused by impact or falling, and further improving the stability of the optical waveguide assembly 100.
[0061] It should be noted that when the refractive index n1 of the first waveguide plate 20 is 2.6, the first waveguide plate 20 can be made of silicon carbide material, and when the refractive index n2 of the second waveguide plate 30 is 1.62, the second waveguide plate 30 can be made of conventional optical glass. At this time, the diagonal field of view F of the optical waveguide assembly can reach 40°.
[0062] Please continue to refer to Figures 2-3 In some optional embodiments, the coupling-in element 21 and the turning element 22 are gratings, and the coupling-out element 31 is an array beam splitter.
[0063] It should be noted that in a conventional two-dimensional array optical waveguide, the turning structure and the coupling-out structure are both array beam splitters, and in the cold processing technology for manufacturing the array optical waveguide, there are many processes for cutting the waveguide plate. Since silicon carbide has high strength, its strength is only second to that of diamond, so it is difficult to cut the first waveguide plate 20 formed by the silicon carbide plate. At the same time, even if the two-dimensional array optical waveguide is made of conventional strength optical glass, when the first waveguide plate 20 is thin, the spacing between the film layers of the array beam splitter forming the turning structure of the two-dimensional array optical waveguide will be very small. When the glass substrate is very low in thickness, its planar surface shape is difficult to guarantee, and the number of film layers will increase sharply. The parallelism between the planes where all the film layers are located is difficult to guarantee at the same time, which will greatly increase the difficulty of the cold processing technology of the two-dimensional array optical waveguide.
[0064] Therefore, the light waveguide assembly 100 according to the embodiment of the present application can reduce the process difficulty of the light waveguide assembly 100 and reduce the production cost of the light waveguide assembly 100 by setting the coupling-in element 21 and the turning element 22 on the first waveguide plate 20 and setting the coupling-in element 21 and the turning element 22 as gratings.
[0065] It can be understood that the coupling-in element 21 and the turning element 22 can be formed on the first waveguide plate 20 by etching gratings on the surface of the first waveguide plate 20, or the coupling-in element 21 and the turning element 22 can also be formed on the surface of the first waveguide plate 20 by nano-imprinting, and the embodiment of the present application does not limit this.
[0066] In addition, since the grating will cause different degrees of deflection to light rays of different wavelengths, in a conventional two-dimensional diffraction light waveguide, since the coupling-in element 21, the turning element 22 and the coupling-out element 31 are all gratings, the dispersion of the light rays coupled out in the two-dimensional diffraction light waveguide is very large, which causes chromatic aberration of the image and reduces the imaging quality.
[0067] Therefore, the light waveguide assembly 100 according to the embodiment of the present application can reduce the process difficulty of the light waveguide assembly 100 and reduce the production cost of the light waveguide assembly 100 by setting the coupling-in element 21 and the turning element 22 on the first waveguide plate 20 and setting the coupling-in element 21 and the turning element 22 as gratings.
[0068] Of course, in other embodiments of the present application, the coupling-in element 21 can also be a prism or a mirror, the turning element 22 can also be an array spectroscope, and the coupling-out element 31 can also be a grating, and the embodiment of the present application does not limit this.
[0069] Please refer to Figure 4 In some optional embodiments, the coupling-in element 21 is a reflective grating, the first waveguide plate 20 includes opposite first and second surfaces, the reflective grating is arranged on the first surface, the second waveguide plate 30 is arranged on the second surface, and the light engine 10 is arranged on the side of the second waveguide plate 30 away from the first waveguide plate 20.
[0070] Therefore, the reflective grating has high diffraction efficiency, which can improve the light utilization rate and further improve the imaging quality of the light waveguide assembly 100.
[0071] In some optional embodiments, the arrayed beam splitter comprises a plurality of beam splitters 311, and reflectivities of the plurality of beam splitters 311 gradually increase in the direction of light propagation.
[0072] It should be noted that the plurality of beam splitters 311 are arranged in an array in the direction of light propagation to form the arrayed beam splitter, and the reflectivities of the plurality of beam splitters 311 gradually increase in the direction of light propagation, that is, as the expanded light is transmitted by total reflection in the first waveguide plate 20 and the second waveguide plate 30, the proportion of light reflected by the beam splitter 311 is higher and higher, that is, when the expanded light is transmitted to the first beam splitter 311, the proportion of the reflected expanded light is the lowest, and the proportion of the reflected expanded light by the beam splitter 311 farther in the direction of light propagation is higher, so that the uniformity of the exit image can be improved, and the imaging quality of the optical waveguide assembly 100 is further improved.
[0073] In some embodiments, the first waveguide plate 20 and the second waveguide plate 30 are formed into one body by a bonding process. It can be understood that the bonding process refers to a method of connecting two or more materials together by chemical and / or physical action, and in the manufacture of an optical waveguide, bonding is an important process step, and through the bonding process, two or more waveguide plates of different material layers can be combined together to form a complete optical waveguide device.
[0074] Therefore, the optical waveguide assembly 100 of the embodiment of the present application can reduce light loss by using the bonding process to form the first waveguide plate 20 and the second waveguide plate 30 into one body, and the first waveguide plate 20 and the second waveguide plate 30 after bonding maintain high transparency, thereby further improving the imaging quality of the optical waveguide assembly 100; at the same time, since the first waveguide plate 20 and the second waveguide plate 30 do not need to be provided with a glue layer, the thickness and weight of the optical waveguide assembly 100 can be reduced, and user experience is improved.
[0075] Specifically, the first waveguide plate 20 and the second waveguide plate 30 can be formed into one body by direct bonding or plasma activated bonding, wherein the direct bonding refers to a bonding process in which high temperature and high pressure make atoms on the surface of the material directly bond, and the plasma activated bonding refers to a process of treating the surface of the material by plasma to enhance the bonding activity, and then bonding, of course, the embodiment of the present application is not limited to the above two bonding methods, as long as the first waveguide plate 20 and the second waveguide plate 30 can be bonded into one body.
[0076] In some other embodiments of the present application, the first waveguide plate 20 and the second waveguide plate 30 can also be bonded by optical glue, and the embodiments of the present application do not limit this.
[0077] Please refer to Figure 5In some embodiments, an anti-reflection film 40 is arranged between the first waveguide plate 20 and the second waveguide plate 30.
[0078] It should be noted that, since the refractive indexes of the first waveguide plate 20 and the second waveguide plate 30 are different, when the expanded light rays are transmitted from the first waveguide plate 20 to the second waveguide plate 30, or the expanded light rays are transmitted from the second waveguide plate 30 to the first waveguide plate 20, the reflectivity of the light rays at the interface between the first waveguide plate 20 and the second waveguide plate 30 is high, which may cause part of the light rays to be lost.
[0079] Therefore, by arranging the anti-reflection film 40 between the first waveguide plate 20 and the second waveguide plate 30, the reflection at the interface between the first waveguide plate 20 and the second waveguide plate 30 can be reduced, so that more expanded light rays can be transmitted from the first waveguide plate 20 to the second waveguide plate 30, or more expanded light rays can be transmitted from the second waveguide plate 30 to the first waveguide plate 20, so that more expanded light rays can be totally reflected and transmitted between the first waveguide plate 20 and the second waveguide plate 30, and the imaging quality of the optical waveguide assembly 100 is further improved.
[0080] In some other embodiments, the anti-reflection film 40 can be arranged only between the first waveguide plate 20 and the second waveguide plate 30 after the turning element 22, that is, the anti-reflection film 40 is arranged only on the path of the expanded light rays which are totally reflected and transmitted between the first waveguide plate 20 and the second waveguide plate 30 after the light rays are expanded by the turning element 22 in the first direction.
[0081] Please refer to Figure 6 In some embodiments, a semi-reflective and semi-transmissive film 50 is arranged between the first waveguide plate 20 and the second waveguide plate 30.
[0082] It should be noted that, before the light rays are transmitted to the turning element 22, the light rays are totally reflected and transmitted only in the first waveguide plate 20, and after the light rays are expanded by the turning element 22, the expanded light rays are transmitted in the first waveguide plate 20 and the second waveguide plate 30, which may cause the expanded light rays to not fill the entire first waveguide plate 20 and / or the second waveguide plate 30, that is, there is a part of the position of the second waveguide plate 30 where there is light and a part of the position where there is no light, which may affect the display effect of the optical waveguide assembly 100.
[0083] Therefore, according to the light wave guide assembly 100, when the expanded light is emitted from the first wave guide plate 20 to the second wave guide plate 30 or emitted from the second wave guide plate 30 to the first wave guide plate 20, the half-reflecting half-transmitting film 50 can reflect a part of the expanded light and transmit another part of the expanded light, and the transmission path of the expanded light reflected by the half-reflecting half-transmitting film 50 is different from the transmission path of the expanded light transmitted by the half-reflecting half-transmitting film 50, so that the expanded light can fill the entire first wave guide plate 20 and the second wave guide plate 30 as much as possible, and the uniformity of the light wave guide assembly 100 is further improved, and the imaging quality of the light wave guide assembly 100 is improved.
[0084] Please refer to Figure 7 In some other embodiments, the light wave guide assembly 100 can further include an adjusting plate 60, the adjusting plate 60 is arranged on the side of the first wave guide plate 20 away from the second wave guide plate 30, and the adjusting plate 60 is arranged after the turning element 22, and the half-reflecting half-transmitting film 50 is arranged between the first wave guide plate 20 and the adjusting plate 60, wherein when the expanded light totally reflected between the first wave guide plate 20 and the second wave guide plate 30 is transmitted to the adjusting plate 60, since the half-reflecting half-transmitting film 50 is arranged between the first wave guide plate 20 and the adjusting plate 60, a part of the expanded light is reflected by the half-reflecting half-transmitting film 50 and continues to be totally reflected between the first wave guide plate 20 and the second wave guide plate 30, and another part of the expanded light is transmitted into the adjusting plate 60 by the half-reflecting half-transmitting film 50 and then enters the first wave guide plate 20 and the second wave guide plate 30 again after being totally reflected by the adjusting plate 60, so that the expanded light can fill the entire first wave guide plate 20 and the second wave guide plate 30 as much as possible, and the uniformity of the light wave guide assembly 100 is further improved, and the imaging quality of the light wave guide assembly 100 is improved.
[0085] Of course, the adjusting plate 60 can also be arranged on the side of the second wave guide plate 30 away from the first wave guide plate 20, and the half-reflecting half-transmitting film 50 is arranged between the adjusting plate 60 and the second wave guide plate 30, and the principle is similar to that of the adjusting plate 60 arranged on the side of the first wave guide plate 20 away from the second wave guide plate 30, and details are not repeated here. The adjusting plate can be a glass plate or the like.
[0086] It should be noted that the above-mentioned beam splitter 311, half-reflecting half-transmitting film 50 and the like do not mean that the reflectivity or transmissivity of the beam splitter 311 or the half-reflecting half-transmitting film 50 is 50%, and in the embodiments of the present application, the reflectivity and transmissivity of the beam splitter 311, the half-reflecting half-transmitting film 50 and the like can be adjusted as needed, and the embodiments of the present application do not limit this.
[0087] According to the AR glasses of the second aspect of the present application, the optical waveguide assembly 100 according to the first aspect of the present application is included. Specifically, the AR glasses can further include a frame and a temple, wherein the first waveguide plate 20 and the second waveguide plate 30 in the optical waveguide assembly 100 can be arranged in the frame, and the light machine 10 can be arranged on the temple, so that the weight distribution of the AR glasses is more uniform, and the user experience is improved. Moreover, when the AR glasses are binocular glasses, the AR glasses can be provided with two frames. Understandably, the light machine 10 can emit light rays of a virtual image, and the light rays of the virtual image are transmitted to the human eye through the transmission of the first waveguide plate 20 and the second waveguide plate 30. At the same time, the first waveguide plate 20 and the second waveguide plate 30 are transparent plates, and the human eye can directly see the picture of the real world through the first waveguide plate 20 and the second waveguide plate 30, so as to realize augmented reality display.
[0088] Understandably, according to the AR glasses of the embodiment of the present application, by arranging the above-mentioned optical waveguide assembly 100, it can be ensured that the coupled-in light rays will not enter the second waveguide plate 30 and will not be coupled out from the coupling-out element 31 before being expanded by the turning element 22, so as to avoid the generation of ghost image light rays, improve the imaging quality of the optical waveguide assembly 100, and further improve the overall performance of the AR glasses.
[0089] The other configurations and operations of the optical waveguide assembly 100 and the AR glasses according to the embodiment of the present application are known to those skilled in the art, and will not be described in detail here.
[0090] In the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.
[0091] In addition, the terms "first" and "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.
[0092] In the utility model, unless another definite provision and limitation, the terms "mount", "link", "connect", "fix" and so on should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, or be integrated;Can be mechanical connection, also can be electric connection, still can be communication;Can be direct connection, also can indirectly connect through intermediate medium, can be the communication of two element internals or the interaction relationship of two elements. For ordinary skilled in the art, can understand the specific meaning of the above terms in the utility model according to specific circumstances.
[0093] In the utility model, unless another definite provision and limitation, the terms "mount", "link", "connect", "fix" and so on should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, or be integrated;Can be mechanical connection, also can be electric connection, still can be communication;Can be direct connection, also can indirectly connect through intermediate medium, can be the communication of two element internals or the interaction relationship of two elements. For ordinary skilled in the art, can understand the specific meaning of the above terms in the utility model according to specific circumstances.
[0094] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present utility model. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of different embodiments or examples without contradiction.
[0095] Although the embodiments of the utility model have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and purposes of the utility model, and the scope of the utility model is defined by the claims and its equivalents.
Claims
1. An optical waveguide component, characterized in that, The optical waveguide component includes: An optical engine, which is used to emit light; The first waveguide plate is provided with a coupling element and a turning element, and the refractive index of the first waveguide plate is n1. The second waveguide plate is stacked with the first waveguide plate, and the second waveguide plate is provided with a coupling element. The refractive index of the second waveguide plate is n2. The light emitted by the optomechanical system enters the first waveguide plate through the coupling element and is transmitted by total internal reflection within the first waveguide plate before being directed toward the deflection element. The deflection element expands the light in a first direction to form an extended ray and directs the extended ray toward the second waveguide plate, so that the extended ray is transmitted by total internal reflection between the first and second waveguide plates. After being transmitted by total internal reflection through the first and second waveguide plates, the extended ray is directed toward the coupling element. The coupling element expands the extended ray in a second direction and couples the extended ray out to form an image, wherein the first direction and the second direction have an angle, and n1>n2.
2. The optical waveguide assembly according to claim 1, characterized in that, The refractive index n1 of the first waveguide plate and the refractive index n2 of the second waveguide plate satisfy: 2*arcsin[sin(1 / 2*F) / n1]<90°-arcsin(n2 / n1); 2*arcsin[sin(1 / 2*F) / n1] <arcsin(n2 / n1)-arcsin(1 / n1); 2*arcsin[sin(1 / 2*F) / n2]<90°-arcsin(1 / n2); Wherein, F is the diagonal field of view of the optical waveguide component.
3. The optical waveguide assembly according to claim 2, characterized in that, The first waveguide plate is a silicon carbide plate, and the second waveguide plate is a glass plate.
4. The optical waveguide assembly according to claim 3, characterized in that, The coupling element and the turning element are gratings, and the coupling element is an array beam splitter.
5. The optical waveguide assembly according to claim 4, characterized in that, The coupling element is a reflective grating. The first waveguide plate includes a first surface and a second surface opposite to each other. The reflective grating is disposed on the first surface, and the second waveguide plate is disposed on the second surface. The optomechanical system is disposed on the side of the second waveguide plate away from the first waveguide plate.
6. The optical waveguide assembly according to claim 4, characterized in that, The array beam splitter includes multiple beam splitters, and the reflectivity of the multiple beam splitters gradually increases along the direction of light propagation.
7. The optical waveguide assembly according to any one of claims 1-6, characterized in that, The first waveguide plate and the second waveguide plate are formed into one piece by a bonding process.
8. The optical waveguide assembly according to claim 1, characterized in that, An antireflection coating is provided between the first waveguide plate and the second waveguide plate.
9. The optical waveguide assembly according to claim 1, characterized in that, A semi-reflective and semi-permeable membrane is disposed between the first waveguide plate and the second waveguide plate.
10. An AR glasses, characterized in that, Includes the optical waveguide component as described in any one of claims 1-9.