CN-224216901-U - Optical waveguide assembly, near-eye display device and optical device

CN224216901UCN 224216901 UCN224216901 UCN 224216901UCN-224216901-U

Abstract

The utility model discloses an optical waveguide assembly, a near-to-eye display device and an optical device, wherein the optical waveguide assembly comprises an optical waveguide assembly, the optical waveguide assembly comprises a composite layer, a grating and a reflecting layer, the composite layer comprises a plurality of dielectric layers, the dielectric layers comprise a first dielectric layer positioned on a surface layer, a total reflection area is formed in at least the first dielectric layer, the grating is arranged on the same side of the first dielectric layer, the coupling-in grating is used for coupling in light rays entering the total reflection area to form total reflection propagation, the coupling-out grating is used for coupling at least part of the light rays of the total reflection area out of the composite layer, and the reflecting layer is optionally arranged in a plurality of areas on the outer side surface of the first dielectric layer and used for reflecting the light rays of the total reflection area to enable the light rays to continue to propagate along the total reflection path. According to the optical waveguide assembly disclosed by the utility model, on the premise that the reflective layers arranged at intervals can enable light rays to be transmitted in a total reflection mode, external light rays can be transmitted to the composite layer, and the light efficiency and contrast display effect are ensured.

Inventors

XU SONG
ZHOU XING
WANG ZHAOMIN

Assignees

珠海莫界科技有限公司

Dates

Publication Date: 20260508
Application Date: 20250530

Claims (14)

1. An optical waveguide assembly, comprising: The composite layer comprises a plurality of dielectric layers, wherein the dielectric layers comprise first dielectric layers, the first dielectric layers are positioned on the surface layers, and a total reflection area is formed at least in the first dielectric layers; The grating is arranged on the same side of the first dielectric layer, the grating comprises a coupling-in grating and a coupling-out grating, the coupling-in grating is used for coupling light rays entering the composite layer into the total reflection area to form total reflection propagation, and the coupling-out grating is used for coupling at least part of the light rays of the total reflection area out of the composite layer; The reflecting layer is arranged on the outer side surface of the first dielectric layer, the reflecting layer reflects the light rays of the total reflection area to enable the light rays to continuously propagate along a total reflection path, the reflecting layer is optionally arranged in a plurality of areas on the outer side surface of the first dielectric layer, and the reflecting layer in at least one area is distributed at intervals.
2. The optical waveguide assembly of claim 1 wherein the light is incident through the incoupling grating into a total reflection region of the first dielectric layer, the region of the outer surface of the first dielectric layer that is reached during total reflection of the light being a first region, the reflection layer being disposed in a portion of the first region, and/or, The reflecting layer is arranged in a second area of the first dielectric layer, which is opposite to the coupling-in grating, and/or, The reflective layer is disposed in a third region of the first dielectric layer susceptible to contamination.
3. The optical waveguide assembly of claim 2 wherein the reflective layer is disposed in the first region, the reflective layer being disposed in an array on an outer surface of the first dielectric layer in a direction parallel to the extension of the total reflection region, or The light rays have a period when being transmitted in the total reflection area in a total reflection way, the reflection layer is arranged in the first area, and a plurality of reflection layers are uniformly arranged on the first medium layer at intervals.
4. The optical waveguide assembly of claim 3 wherein the same reflective layer is used to reflect light passing once through the outer surface of the first dielectric layer when total reflection propagation is formed in the total reflection region, the light being formed by total reflection of light beam edge light rays having the same incident angle and furthest from the first dielectric layer in the total reflection region, the reflective layer reflecting the light rays back to the total reflection region, and the minimum dimension of the reflective layer is greater than or equal to the displacement difference of the light beam edge light rays first propagating to the outer surface of the first dielectric layer.
5. The optical waveguide assembly of claim 3 wherein the number of reflective layers disposed on the surface of the first dielectric layer closer to the in-coupling grating is greater than the number of reflective layers disposed on the surface of the first dielectric layer closer to the out-coupling grating, or the sum of the areas of the cross-sections of the reflective layers disposed on the surface of the first dielectric layer closer to the in-coupling grating is greater than the sum of the areas of the cross-sections of the reflective layers disposed on the surface of the first dielectric layer closer to the out-coupling grating.
6. The optical waveguide assembly of claim 3 wherein the displacement of the reflective layer disposed on the outer surface of the first dielectric layer is positively correlated with the position of the point of incidence of the light ray in the total reflection region, with the diffraction angle of the light ray in the total reflection region, with the thickness of the total reflection region, and with the number of times the light ray propagates in the total reflection region, respectively.
7. The optical waveguide assembly of claim 2 wherein the reflective layer is disposed in the second region, the reflective layer being disposed annularly on an outer surface of the first dielectric layer, or a plurality of the reflective layers being disposed concentrically and at intervals with respect to a perpendicular line passing through the outer surface of the first dielectric layer at a geometric center of the coupling grating.
8. The optical waveguide assembly of any one of claims 1-7, wherein the dielectric layer further comprises a second dielectric layer and a third dielectric layer, opposite sides of the second dielectric layer being respectively connected to the first dielectric layer and the third dielectric layer; The reflecting layer is arranged on the outer side surface of the first dielectric layer far away from the second dielectric layer only under the condition that a total reflection area is formed in the first dielectric layer; the reflection layer is arranged on the outer side surface of the first dielectric layer far away from the second dielectric layer under the condition that the total reflection area is formed in the first dielectric layer and the second dielectric layer simultaneously; And under the condition that total reflection areas are formed in the first dielectric layer, the second dielectric layer and the third dielectric layer at the same time, part of the reflection layer is arranged on the outer side surface of the first dielectric layer, which is far away from the second dielectric layer, and part of the reflection layer is arranged on the surface of the third dielectric layer, which is far away from the second dielectric layer.
9. The optical waveguide assembly of claim 8 wherein the first dielectric layer has a refractive index greater than the refractive index of the second dielectric layer, the first dielectric layer having a refractive index greater than that of air, the total reflection region being formed in the first dielectric layer, or The first and second dielectric layers are made of different materials and have the same refractive index, the refractive index of the first and second dielectric layers is larger than that of the third dielectric layer, and the refractive index of the first and second dielectric layers is larger than that of air, so that the total reflection region is formed in the first and second dielectric layers The first dielectric layer, the second dielectric layer and the third dielectric layer are different in material and are approximately the same in refractive index, and the refractive indexes of the first dielectric layer, the second dielectric layer and the third dielectric layer are larger than that of air, so that the total reflection area is formed in the first dielectric layer, the second dielectric layer and the third dielectric layer.
10. The optical waveguide assembly of claim 8 wherein when the second dielectric layer is an air layer, the composite layer further comprises an adhesive layer connected at an edge region between the third dielectric layer and the first dielectric layer, and the reflective layer is disposed on an outer surface of the first dielectric layer remote from the second dielectric layer.
11. The optical waveguide assembly of any one of claims 1-7, wherein the reflective layer comprises a metallic reflective film or a multilayer dielectric reflective film.
12. The optical waveguide assembly of claim 11 wherein the reflective layer is a metal reflective film having a thickness in the range of 200nm to 400nm, or wherein the reflective layer is a multilayer dielectric reflective film having a thickness in the range of 300nm to 400nm.
13. A near-eye display device, comprising: the optical machine is used for emitting signal light; The optical waveguide assembly of any one of claims 1-12, the optomachine being disposed in correspondence with the incoupling grating.
14. An optical device comprising the optical waveguide assembly of any one of claims 1 to 12.

Description

Optical waveguide assembly, near-eye display device and optical device Technical Field The utility model relates to the technical field of optical devices, in particular to an optical waveguide assembly, a near-eye display device and an optical device. Background The optical waveguide is widely used in applications of near-to-eye display devices such as augmented reality and mixed reality due to the characteristics of thin thickness, light weight and good light transmittance. In the existing optical waveguide products, light rays in a total reflection area in an optical waveguide structure are easy to influence the light rays to realize total reflection propagation according to a normal path due to the change of a surface layer state in the propagation process. For example, when the surface is polluted, part of light rays can be absorbed or scattered, so that the light rays in the total reflection area cannot be transmitted to the coupling-out grating according to a preset route and transmitted to human eyes, and the light efficiency of the optical waveguide structure is reduced, the display effects such as contrast ratio are reduced, and the user experience is affected. Disclosure of utility model In view of this, the present utility model provides an optical waveguide assembly, a near-to-eye display device and an optical device, which aim to realize total reflection of light rays in a total reflection area in the optical waveguide assembly according to a predetermined propagation route, and reduce or avoid the influence of the change of the surface state of the optical waveguide assembly on the propagation of the light rays. The optical waveguide component comprises a composite layer, a grating, a coupling-in grating and a coupling-out grating, wherein the composite layer comprises a plurality of dielectric layers, the dielectric layers comprise a first dielectric layer, the first dielectric layer is arranged on a surface layer, a total reflection area is formed at least in the first dielectric layer, the grating is arranged on the same side of the first dielectric layer, the coupling-in grating is used for coupling light rays entering the composite layer into the total reflection area to form total reflection propagation, the coupling-out grating is used for coupling at least part of the light rays of the total reflection area out of the composite layer, the reflecting layer is arranged on the outer side surface of the first dielectric layer, the reflecting layer reflects the light rays of the total reflection area to enable the light rays to continuously propagate along a total reflection path, the reflecting layer is optionally arranged on a plurality of areas on the outer side surface of the first dielectric layer, and the reflecting layer in at least one area is arranged at intervals. According to the technical scheme, when light is incident into the composite layer, the coupling grating couples the light into the total reflection area to form total reflection propagation, when the light passes through the first dielectric layer on the surface layer in the total reflection propagation process, the reflecting layer arranged on the outer side surface of the first dielectric layer reflects the light to the total reflection area, so that the light can propagate along a preset total reflection path, the influence of surface state change of the outer side surface of the first dielectric layer on the total reflection propagation of the light is reduced, and the reflecting layers arranged on the outer side surface of the first dielectric layer at intervals can prevent external light from being transmitted to the composite layer on the premise of ensuring that the light can realize the total reflection propagation, reduce or avoid interference with the visible area of human eyes, ensure that the waveguide luminous efficacy of the whole optical waveguide assembly is kept within a preset threshold, ensure the contrast display effect of the whole optical waveguide assembly, and improve user experience. In some possible embodiments of the present utility model, the light is incident to the total reflection area of the first dielectric layer through the coupling-in grating, the area of the outer side surface of the first dielectric layer reached in the total reflection process of the incident light is a first area, the reflection layer is disposed in a part of the first area, and/or the reflection layer is disposed in a second area of the first dielectric layer opposite to the coupling-in grating, and/or the reflection layer is disposed in a third area of the first dielectric layer which is easy to be polluted. In some further embodiments of the present utility model, the reflective layer is disposed in the first region, and the reflective layer is configured to be disposed in an array on an outer surface of the first dielectric layer in a direction parallel to an extension direction of the total reflection region