Diffractive waveguide

Abstract

The utility model provides a diffraction optical waveguide. The diffraction optical waveguide comprises: a substrate; an out-coupling etched grating area, the out-coupling etched grating area is arranged on the substrate; an imprinted layer, the imprinted layer and the out-coupling etched grating area are located on the same side surface of the substrate, and the out-coupling etched grating area is filled and covered by the imprinted layer, and the side surface of the imprinted layer away from the substrate has an in-coupling imprinted grating area, and the angle between the grating of the out-coupling etched grating area and the substrate is different from the angle between the grating of the in-coupling imprinted grating area and the substrate. The utility model solves the problem of difficulty in improving the optical performance of the diffraction optical waveguide in the prior art.

Description

Technical Field

[0001] The utility model relates to the technical field of diffraction optics, in particular to a diffraction optical waveguide. Background Art

[0002] At present, diffraction waveguides usually use surface relief gratings to achieve light diffraction. In the processing of diffraction waveguides with surface relief gratings, two methods are usually used to complete the processing of key gratings, such as embossing process and etching process. These two processes complete the processing of the entire diffraction waveguide separately. The embossing process can realize the processing of tilted gratings and blazed gratings, but due to the limitations of process and materials, the refractive index of the grating cannot reach greater than 2.0, which limits the optical performance of the product. Although the etching process can realize the processing of gratings with a refractive index greater than 2.0, due to process limitations, it is impossible to produce large-scale batch processing of tilted gratings and blazed gratings, which also limits the optical performance of the product.

[0003] In other words, the diffraction optical waveguide in the prior art has the problem of difficulty in improving the optical performance. Utility Model Content

[0004] The main purpose of the utility model is to provide a diffractive optical waveguide to solve the problem that it is difficult to improve the optical performance of the diffractive optical waveguide in the prior art.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the utility model, a diffraction optical waveguide is provided, comprising: a substrate; an out-coupling etched grating region, the out-coupling etched grating region is arranged on the substrate; an imprinted layer, the imprinted layer and the out-coupling etched grating region are located on the same side surface of the substrate, and the out-coupling etched grating region is filled and covered by the imprinted layer, and a side surface of the imprinted layer away from the substrate has a coupling-in imprinted grating region, and the angle between the grating of the out-coupling etched grating region and the substrate is different from the angle between the grating of the coupling-in imprinted grating region and the substrate.

[0006] Furthermore, the imprinted layer includes a first imprinted layer and a second imprinted layer along a direction parallel to the substrate, the first imprinted layer has a coupling-in imprinted grating area on a surface away from the substrate, the second imprinted layer fills and covers the coupling-out etched grating area, and the thickness of the first imprinted layer and the second imprinted layer are the same or different.

[0007] Furthermore, the projection of the in-coupling imprinted grating region on the substrate is spaced apart from the projection of the out-coupling etched grating region on the substrate, the grating of the out-coupling etched grating region is perpendicular to the substrate, and the grating of the in-coupling imprinted grating region is inclined to the substrate.

[0008] Furthermore, the distance from the in-coupling imprinted grating region to the substrate is greater than the height of the out-coupling etched grating region.

[0009] Furthermore, the distance from the surface of the second imprinted layer away from the substrate to the surface of the out-coupling etched grating region away from the substrate is greater than 0 nm and less than or equal to 1000 nm; and / or the thickness of the first imprinted layer is greater than 0 nm and less than or equal to 1000 nm.

[0010] Furthermore, a surface of the imprinted layer on one side away from the substrate further comprises an out-coupling imprinted grating region, and the out-coupling imprinted grating region corresponds to the out-coupling etched grating region.

[0011] Further, the distance from the out-coupling imprinted grating region to the substrate is equal to the distance from the in-coupling imprinted grating region to the substrate, and the projection of the out-coupling imprinted grating region on the out-coupling etched grating region at least partially covers the out-coupling etched grating region.

[0012] Furthermore, the out-coupling etched grating region is a one-dimensional grating or a two-dimensional grating. When the out-coupling etched grating region is a one-dimensional grating, the diffraction optical waveguide also includes a turning etched grating region, and the turning etched grating region and the out-coupling etched grating region are arranged on one side surface of the substrate at intervals, and the turning etched grating region is filled and covered by the imprinted layer, and the grating of the turning etched grating region is arranged perpendicular to the substrate.

[0013] Furthermore, a surface of the imprinted layer on one side away from the substrate also has a turning imprinted grating region and an out-coupling imprinted grating region, the turning imprinted grating region corresponds to the turning etched grating region, and the out-coupling imprinted grating region corresponds to the out-coupling etched grating region.

[0014] Furthermore, the refractive indices of the turning etched grating region and the coupling-out etched grating region are both greater than or equal to 2.0 and less than or equal to 2.4; and / or the refractive indices of the coupling-in imprinted grating region, the turning imprinted grating region and the coupling-out imprinted grating region are all greater than or equal to 1.5 and less than or equal to 2.0.

[0015] Further, the out-coupling etched grating region includes one of a TiO2 grating, a SiO2 grating, a ZrO2 grating, a SiN grating and a SiC grating, and the in-coupling imprinted grating region includes an imprinted glue structure.

[0016] By applying the technical solution of the utility model, a diffraction optical waveguide comprises a substrate, an out-coupling etched grating area and an imprinted layer, wherein the out-coupling etched grating area is arranged on the substrate; the imprinted layer and the out-coupling etched grating area are located on the same side surface of the substrate, and the out-coupling etched grating area is filled and covered by the imprinted layer, and a side surface of the imprinted layer away from the substrate has an in-coupling imprinted grating area, and an angle between the grating of the out-coupling etched grating area and the substrate is different from an angle between the grating of the in-coupling imprinted grating area and the substrate.

[0017] The out-coupling etched grating area is filled and covered by the imprinted layer, so that a refractive index difference is formed between the imprinted layer and the out-coupling etched grating area. Since the out-coupling etched grating area is formed by an etching process, a material with a higher refractive index can be used to ensure the high diffraction efficiency of the out-coupling etched grating area. At the same time, the in-coupling imprinted grating area is formed by an imprinting process, and different tilt angles can be achieved, so that the angle between the grating of the out-coupling etched grating area and the substrate is different from the angle between the grating of the in-coupling imprinted grating area and the substrate. By matching different materials and tilt angles of the two grating areas, higher light transmission efficiency and better color uniformity are achieved, thereby improving the performance of the diffraction optical waveguide. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0019] Figure 1 A top view of the diffractive optical waveguide of the first embodiment of the utility model is shown;

[0020] Figure 2 Two side views of the diffractive optical waveguide of the first embodiment of the utility model are shown;

[0021] Figure 3 A top view of the diffractive optical waveguide of the second embodiment of the utility model is shown;

[0022] Figure 4 Two side views of the diffractive optical waveguide of the second embodiment of the utility model are shown;

[0023] Figure 5 A top view of the diffractive optical waveguide of the third embodiment of the present utility model is shown;

[0024] Figure 6 Two side views of the diffractive optical waveguide of the third embodiment of the utility model are shown;

[0025] Figure 7 A top view of a diffractive optical waveguide according to a fourth embodiment of the present utility model is shown;

[0026] Figure 8 Two side views of the diffractive optical waveguide of the fourth embodiment of the utility model are shown;

[0027] Fig. 9 The figure shows a processing flow chart of the diffraction optical waveguide according to the first embodiment of the utility model.

[0028] The above drawings include the following reference numerals:

[0029] 10. Substrate; 21. Turning etched grating region; 22. Out-coupling etched grating region; 31. First imprinted layer; 32. Second imprinted layer; 41. In-coupling imprinted grating region; 42. Turning imprinted grating region; 43. Out-coupling imprinted grating region. DETAILED DESCRIPTION

[0030] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present utility model will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0031] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0032] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above-mentioned directional words are not used to limit the present invention.

[0033] In order to solve the problem that it is difficult to improve the optical performance of the diffraction optical waveguide in the prior art, the utility model provides a diffraction optical waveguide.

[0034] like Figures 1 to 9 As shown, the diffraction optical waveguide includes a substrate 10, an out-coupling etched grating area 22 and an imprinted layer, wherein the out-coupling etched grating area 22 is arranged on the substrate 10; the imprinted layer and the out-coupling etched grating area 22 are located on the same side surface of the substrate 10, and the out-coupling etched grating area 22 is filled and covered by the imprinted layer, and a side surface of the imprinted layer away from the substrate 10 has a coupling-in imprinted grating area 41, and the angle between the grating of the out-coupling etched grating area 22 and the substrate 10 is different from the angle between the grating of the coupling-in imprinted grating area 41 and the substrate 10.

[0035] The imprinted layer is filled and covered by the imprinted layer by setting the out-coupling etched grating area 22, so that a refractive index difference is formed between the imprinted layer and the out-coupling etched grating area 22. Since the out-coupling etched grating area 22 is formed by an etching process, a material with a higher refractive index can be used to ensure the high diffraction efficiency of the out-coupling etched grating area 22. At the same time, the coupling-in imprinted grating area 41 is formed by an imprinting process, and different tilt angles can be achieved, so that the angle between the grating of the out-coupling etched grating area 22 and the substrate 10 is different from the angle between the grating of the coupling-in imprinted grating area 41 and the substrate 10. By matching different materials and tilt angles of the two grating areas, higher light transmission efficiency and better color uniformity are achieved, thereby improving the performance of the diffraction optical waveguide.

[0036] It should be noted that the gratings of the above-mentioned out-coupling etched grating area 22 and the coupling-in imprinted grating area 41 are both periodic relief gratings. And the out-coupling etched grating area 22 is an etched structure, that is, the out-coupling etched grating area 22 is made by an etching process. The coupling-in imprinted grating area 41 and the imprinting layer are integrally formed, and the two materials are the same, both of which are imprinted glue structures. Due to the different manufacturing processes, the out-coupling etched grating area 22 and the coupling-in imprinted grating area 41 have different materials and different refractive indices.

[0037] In the present application, the imprinted layer includes a first imprinted layer 31 and a second imprinted layer 32 along a direction parallel to the substrate 10. The first imprinted layer 31 has a coupling-in imprinted grating area 41 on the surface of the side away from the substrate 10. The second imprinted layer 32 fills and encapsulates the coupling-out etched grating area 22. The thicknesses of the first imprinted layer 31 and the second imprinted layer 32 are the same or different. Since the thicknesses of the first imprinted layer 31 between the coupling-in imprinted grating area 41 and the substrate 10 and the second imprinted layer 32 encapsulating the coupling-out etched grating area 22 are controlled separately, in other optional embodiments, the thickness of the first imprinted layer 31 and the thickness of the second imprinted layer 32 can be set to be the same. However, in the present application, the thickness of the first imprinted layer 31 and the thickness of the second imprinted layer 32 are different. And in specific processing, the first imprinted layer 31 and the second imprinted layer 32 can be set to be seamlessly connected or gap-connected.

[0038] Specifically, the projection of the coupled-in imprinted grating area 41 on the substrate 10 is spaced apart from the projection of the coupled-out etched grating area 22 on the substrate 10, the grating of the coupled-out etched grating area 22 is perpendicular to the substrate 10, and the grating of the coupled-in imprinted grating area 41 is tilted to the substrate 10, that is, the grating of the coupled-in imprinted grating area 41 is not perpendicular to the substrate 10. In different embodiments of the present application, the grating coupled into the imprinted grating area 41 includes one of a blazed grating and a slanted grating. The grating of the coupled-out etched grating area 22 includes a straight grating.

[0039] like Figure 2 and Figure 4 As shown, the distance from the coupling-in imprinted grating region 41 to the substrate 10 is greater than the height of the coupling-out etched grating region 22. Specifically, the distance from the bottom of the coupling-in imprinted grating region 41 to the substrate 10 is greater than the height of the coupling-out etched grating region 22, that is, the coupling-in imprinted grating region 41 and the coupling-out etched grating region 22 are at different heights, the two are arranged in different layers, and the two have a height difference. Specifically, the distance from the coupling-in imprinted grating region 41 to the substrate 10 is equal to the thickness of the first imprinted layer 31, and the distance from the coupling-out etched grating region 22 to the substrate 10 is 0.

[0040] Specifically, the thickness of the first imprinted layer 31 is greater than 0 nm and less than or equal to 1000 nm. The distance from the side surface of the second imprinted layer 32 away from the substrate 10 to the side surface of the out-coupling etched grating area 22 away from the substrate 10 is greater than 0 nm and less than or equal to 1000 nm. In other words, the second imprinted layer 32 is arranged higher than the out-coupling etched grating area 22, and the second imprinted layer 32 fills the gap of the out-coupling etched grating area 22 and completely covers the out-coupling etched grating area 22. Such a setting is beneficial to the protection of the out-coupling etched grating area 22 by the second imprinted layer 32, and at the same time, the cooperation of different materials of the second imprinted layer 32 and the out-coupling etched grating area 22 forms a refractive index difference, thereby improving the diffraction performance. Preferably, the distance from the side surface of the second imprinted layer 32 away from the substrate 10 to the side surface of the out-coupling etched grating area 22 away from the substrate 10 is greater than 0 nm and less than or equal to 100 nm.

[0041] Specifically, the out-coupling etched grating region 22 is a one-dimensional grating or a two-dimensional grating. When the out-coupling etched grating region 22 is a one-dimensional grating, the diffraction optical waveguide further includes a turn etched grating region 21, and the turn etched grating region 21 and the out-coupling etched grating region 22 are arranged on a side surface of the substrate 10 at intervals, and the turn etched grating region 21 is filled and coated by the second imprinted layer 32, and the grating of the turn etched grating region 21 is arranged perpendicular to the substrate 10. Specifically, the turn etched grating region 21 and the out-coupling etched grating region 22 are located at the same height. When the out-coupling etched grating region 22 is a two-dimensional grating, the turn etched grating region 21 may not be provided.

[0042] The diffractive optical waveguide of the present application is described below in conjunction with specific embodiments and drawings.

[0043] Embodiment 1

[0044] like Figure 1 and Figure 2 As shown, the diffractive optical waveguide of the first embodiment is described.

[0045] like Figure 1 and Figure 2As shown, the diffraction optical waveguide includes a substrate 10, a turn etched grating area 21, an out-coupling etched grating area 22, an imprinted layer, and an in-coupling imprinted grating area 41. The imprinted layer is composed of a first imprinted layer 31 and a second imprinted layer 32 along a direction parallel to the substrate 10. The two side surfaces of the substrate 10 are planes, and the turn etched grating area 21 and the out-coupling etched grating area 22 are arranged on the surface of one side of the substrate 10 at intervals, both of which are one-dimensional gratings, and the gratings of the turn etched grating area 21 and the out-coupling etched grating area 22 are both straight tooth gratings, that is, the gratings of the turn etched grating area 21 and the out-coupling etched grating area 22 are perpendicular to the substrate 10. The second imprinted layer 32 covers the side surface of the substrate 10 having the turning etched grating area 21 and the coupling-out etched grating area 22, and the projection of the imprinted layer on the substrate 10 completely covers the substrate 10, and the second imprinted layer 32 fills and covers the turning etched grating area 21 and the coupling-out etched grating area 22. The first imprinted layer 31 is located between the coupling-in imprinted grating area 41 and the substrate 10, and the projection of the coupling-in imprinted grating area 41 on the substrate 10 is spaced from the projection of the turning etched grating area 21 on the substrate 10 and the projection of the coupling-out etched grating area 22 on the substrate 10. Specifically, the line connecting the projection of the coupling-in imprinted grating area 41 on the substrate 10 to the projection of the turning etched grating area 21 on the substrate 10 is perpendicular to the line connecting the projection of the turning etched grating area 21 on the substrate 10 to the projection of the coupling-out etched grating area 22 on the substrate 10. The grating of the coupling-in imprinted grating area 41 is tilted and arranged with respect to the substrate 10.

[0046] In the present embodiment, the turn etched grating area 21 and the coupling-out etched grating area 22 are both formed by an etching process, and the material is a transparent inorganic substance. For example, the coupling-out etched grating area 22 includes one of TiO2 grating, SiO2 grating, ZrO2 grating, SiN grating and SiC grating, and the turn etched grating area 21 includes one of TiO2 grating, SiO2 grating, ZrO2 grating, SiN grating and SiC grating. The refractive index of the turn etched grating area 21 and the coupling-out etched grating area 22 is greater than or equal to 2.0 and less than or equal to 2.4. The imprinted layer and the coupling-in imprinted grating area 41 are formed by an imprinting process, and the materials of both are transparent high-refractive-index imprinted glue structures. The refractive index of the coupling-in imprinted grating area 41 and the imprinted layer is greater than or equal to 1.5 and less than or equal to 2.0. In the present embodiment, the refractive index of the coupling-in imprinted grating area 41 and the imprinted layer is 1.9.

[0047] Figure 2 The side views of two diffraction optical waveguides of this embodiment are shown, the upper side shows a schematic diagram when the coupling-in imprinted grating area 41 adopts a blazed grating, and the cross section of the blazed grating along the direction perpendicular to the substrate 10 is triangular. The lower side shows a schematic diagram when the coupling-in imprinted grating area 41 adopts a slanted grating, and the cross section of the slanted grating along the direction perpendicular to the substrate 10 is a parallelogram. Figure 2The gratings of the upper and lower turning etched grating regions 21 are the same, both are straight tooth gratings, and the cross section of the grating along the direction perpendicular to the substrate 10 is rectangular. Figure 2 The gratings of the upper and lower out-coupling etched grating regions 22 are the same, both are straight-tooth gratings, and the cross-section of the grating along the direction perpendicular to the substrate 10 is rectangular.

[0048] In summary, this embodiment achieves higher light transmission efficiency and better color uniformity in the diffraction optical waveguide by combining the coupling-in imprinted grating area 41 and the turning-etched grating area 21 of different materials, and the coupling-in imprinted grating area 41 and the coupling-out etched grating area 22 of different materials, and setting the gratings of the grating areas of the above-mentioned different materials at different angles with the substrate 10, thereby greatly improving the design freedom and performance of the diffraction optical waveguide.

[0049] Embodiment 2

[0050] like Figure 3 and Figure 4 As shown, the diffractive optical waveguide of the second embodiment is described.

[0051] The difference between this embodiment and the first embodiment is that the out-coupling etched grating region 22 is a two-dimensional grating, and no turning etched grating region 21 is provided. The projection of the in-coupling imprinted grating region 41 on the substrate 10 is spaced apart from the projection of the out-coupling etched grating region 22 on the substrate 10.

[0052] In the present embodiment, the out-coupling etched grating area 22 is formed by an etching process, and the material is a transparent inorganic substance. For example, the out-coupling etched grating area 22 includes one of a TiO2 grating, a SiO2 grating, a ZrO2 grating, a SiN grating, and a SiC grating. The refractive index of the out-coupling etched grating area 22 is greater than or equal to 2.0 and less than or equal to 2.4. The imprinted layer and the coupling-in imprinted grating area 41 are formed by an imprinting process, and the materials of both are transparent high-refractive-index imprinted glue structures. The refractive indices of the coupling-in imprinted grating area 41 and the imprinted layer are both greater than or equal to 1.5 and less than or equal to 2.0. In the present embodiment, the refractive index of the coupling-in imprinted grating area 41 and the imprinted layer is 1.9.

[0053] Figure 4 The side views of two diffraction optical waveguides of this embodiment are shown, the upper side shows a schematic diagram when the coupling-in imprinted grating area 41 adopts a blazed grating, and the cross section of the blazed grating along the direction perpendicular to the substrate 10 is triangular. The lower side shows a schematic diagram when the coupling-in imprinted grating area 41 adopts a slanted grating, and the cross section of the slanted grating along the direction perpendicular to the substrate 10 is a parallelogram. Figure 2 The gratings of the upper and lower out-coupling etched grating regions 22 are the same, both are straight-tooth gratings, and the cross-section of the grating along the direction perpendicular to the substrate 10 is rectangular.

[0054] In summary, this embodiment achieves higher light transmission efficiency and better color uniformity in the diffraction light waveguide by combining the coupling-in imprinted grating area 41 and the coupling-out etched grating area 22 of different materials and setting different angles between the gratings of the grating areas of the above-mentioned different materials and the substrate 10, thereby greatly improving the design freedom and performance of the diffraction light waveguide.

[0055] Embodiment 3

[0056] like Figure 5 and Figure 6 As shown, the diffractive optical waveguide of the third embodiment is described.

[0057] The difference between this embodiment and the first embodiment is that the second imprinted layer 32 further has a turning imprinted grating region 42 and an out-coupling imprinted grating region 43 on the side surface away from the substrate 10, the turning imprinted grating region 42 corresponds to the turning etched grating region 21, and the out-coupling imprinted grating region 43 corresponds to the out-coupling etched grating region 22. Both the turning imprinted grating region 42 and the out-coupling imprinted grating region 43 are arranged obliquely to the substrate 10.

[0058] In this embodiment, the coupling-in imprinted grating region 41, the turning imprinted grating region 42 and the coupling-out imprinted grating region 43 are all located on the surface of the side of the imprinted layer away from the substrate 10. And the distances from the coupling-in imprinted grating region 41, the turning imprinted grating region 42 and the coupling-out imprinted grating region 43 to the substrate 10 are equal. The projection of the turning imprinted grating region 42 on the turning etched grating region 21 at least partially covers the turning etched grating region 21, and the projection of the coupling-out imprinted grating region 43 on the coupling-out etched grating region 22 at least partially covers the coupling-out etched grating region 22.

[0059] Specifically, the distance from the transition imprinted grating region 42 to the transition etched grating region 21 along the direction perpendicular to the substrate 10 is greater than 0 nm and less than or equal to 100 nm. The distance from the outcoupling imprinted grating region 43 to the outcoupling etched grating region 22 along the direction perpendicular to the substrate 10 is greater than 0 nm and less than or equal to 100 nm.

[0060] In the present embodiment, the turning etched grating area 21 and the coupling-out etched grating area 22 are both formed by etching process, and the material is transparent inorganic matter. The refractive index of the turning etched grating area 21 and the coupling-out etched grating area 22 is greater than or equal to 2.0 and less than or equal to 2.4. The imprinted layer, the coupling-in imprinted grating area 41, the turning imprinted grating area 42 and the coupling-out imprinted grating area 43 are all formed by imprinting process, and the material is a transparent high-refractive-index imprinted glue structure. The refractive index of the imprinted layer, the coupling-in imprinted grating area 41, the turning imprinted grating area 42 and the coupling-out imprinted grating area 43 is greater than or equal to 1.5 and less than or equal to 2.0. In the present embodiment, the refractive index of the imprinted layer, the coupling-in imprinted grating area 41, the turning imprinted grating area 42 and the coupling-out imprinted grating area 43 is 1.9.

[0061] Figure 6 The side views of two diffraction optical waveguides of the present embodiment are shown, the upper part shows a schematic diagram when the coupling-in imprinted grating area 41 adopts a blazed grating, the cross section of the blazed grating along the direction perpendicular to the substrate 10 is triangular, the turning imprinted grating area 42 and the coupling-out imprinted grating area 43 both adopt oblique tooth gratings, the cross section of the oblique tooth grating along the direction perpendicular to the substrate 10 is a parallelogram. The lower part shows a schematic diagram when the coupling-in imprinted grating area 41, the turning imprinted grating area 42 and the coupling-out imprinted grating area 43 all adopt oblique tooth gratings, the cross section of the oblique tooth grating along the direction perpendicular to the substrate 10 is a parallelogram. Figure 6 The gratings of the upper and lower turning etched grating regions 21 are the same, both are straight tooth gratings, and the cross section of the grating along the direction perpendicular to the substrate 10 is rectangular. Figure 6 The gratings of the upper and lower out-coupling etched grating regions 22 are the same, both are straight-tooth gratings, and the cross-section of the grating along the direction perpendicular to the substrate 10 is rectangular. Figure 6 The gratings of the turning imprinted grating region 42 and the coupling-out imprinted grating region 43 have the same inclination direction, both of which are tilted to the right. The inclination direction of the coupling-in imprinted grating region 41 is different from that of the turning imprinted grating region 42, and the grating of the coupling-in imprinted grating region 41 is tilted to the left.

[0062] In summary, this embodiment achieves higher light transmission efficiency and better color uniformity in the diffractive light waveguide by combining grating regions of different materials and different angles between the grating regions of different materials and the substrate 10, thereby greatly improving the design freedom and performance of the diffractive light waveguide. Compared with the first embodiment, this embodiment has higher design freedom and better performance.

[0063] Embodiment 4

[0064] like Figure 7 and Figure 8 As shown, the diffractive optical waveguide of the fourth embodiment is described.

[0065] The difference between this embodiment and the second embodiment is that the second imprinted layer 32 further has an out-coupling imprinted grating region 43 on one side of the surface away from the substrate 10, and the out-coupling imprinted grating region 43 corresponds to the out-coupling etched grating region 22. The grating of the out-coupling imprinted grating region 43 is arranged obliquely to the substrate 10.

[0066] In this embodiment, the coupling-in imprinted grating region 41 and the coupling-out imprinted grating region 43 are both located on the surface of the side of the imprinted layer away from the substrate 10. And the distances from the coupling-in imprinted grating region 41 and the coupling-out imprinted grating region 43 to the substrate 10 are equal. The projection of the coupling-out imprinted grating region 43 on the coupling-out etched grating region 22 at least partially covers the coupling-out etched grating region 22. The distance from the coupling-out imprinted grating region 43 to the coupling-out etched grating region 22 is greater than 0 nm and less than or equal to 100 nm.

[0067] In the present embodiment, the out-coupling etched grating area 22 is formed by an etching process, and the material is a transparent inorganic substance. For example, the out-coupling etched grating area 22 is a TiO2 grating. The refractive index of the out-coupling etched grating area 22 is greater than or equal to 2.0 and less than or equal to 2.4. The imprinted layer, the coupling-in imprinted grating area 41 and the out-coupling imprinted grating area 43 are all formed by an imprinting process, and the material is a transparent high-refractive-index imprinted glue structure. The refractive index of the imprinted layer, the coupling-in imprinted grating area 41 and the out-coupling imprinted grating area 43 is greater than or equal to 1.5 and less than or equal to 2.0. In the present embodiment, the refractive index of the imprinted layer, the coupling-in imprinted grating area 41 and the out-coupling imprinted grating area 43 is 1.9.

[0068] Figure 8 The side views of two diffraction optical waveguides of the present embodiment are shown, the upper part shows a schematic diagram when the coupling-in imprinted grating area 41 adopts a blazed grating, the cross section of the blazed grating along the direction perpendicular to the substrate 10 is triangular, and the coupling-out imprinted grating area 43 adopts a slanted grating, the cross section of the slanted grating along the direction perpendicular to the substrate 10 is a parallelogram. The lower part shows a schematic diagram when both the coupling-in imprinted grating area 41 and the coupling-out imprinted grating area 43 adopt slanted grating, the cross section of the slanted grating along the direction perpendicular to the substrate 10 is a parallelogram. Figure 8 The gratings of the upper and lower out-coupling etched grating regions 22 are the same, both are straight-tooth gratings, and the cross-section of the grating along the direction perpendicular to the substrate 10 is rectangular. Figure 8 The grating of the out-coupling imprinted grating region 43 is tilted to the right. The tilting direction of the in-coupling imprinted grating region 41 is different from that of the out-coupling imprinted grating region 43, and the grating of the in-coupling imprinted grating region 41 is tilted to the left.

[0069] In summary, this embodiment achieves higher light transmission efficiency and better color uniformity in the diffractive light waveguide by combining grating regions of different materials and different angles between the grating regions of different materials and the substrate 10, thereby greatly improving the design freedom and performance of the diffractive light waveguide. Compared with the second embodiment, this embodiment has higher design freedom and better performance.

[0070] In addition, the present application also provides a method for processing a diffractive optical waveguide, wherein the diffractive optical waveguide is the diffractive optical waveguide described above, and the processing method comprises:

[0071] Etching treatment: using an etching process to form an out-coupling etched grating region 22 on one side surface of the substrate 10, or forming the out-coupling etched grating region 22 and the turning etched grating region 21;

[0072] Imprinting treatment: An imprinting process is used to form an imprinting layer and an input imprinted grating area 41 on the side surface of the substrate 10 having the output etched grating area 22, or to form an imprinting layer, an input imprinted grating area 41, an output imprinted grating area 43, or an imprinting layer, an input imprinted grating area 41, a turning imprinted grating area 42 and an output imprinted grating area 43.

[0073] Fig. 9 The detailed process of the method for processing the diffractive optical waveguide is described, taking the first embodiment as an example.

[0074] The above etching process includes the following steps:

[0075] Step S11: obtaining a substrate 10, which may be a glass wafer;

[0076] Step S12: depositing a whole layer of inorganic transparent thin film with high refractive index on one side surface of the substrate 10;

[0077] Step S13: depositing a whole metal mask layer on the inorganic transparent thin film layer;

[0078] Step S14: coating a whole layer of photoresist glue or embossing glue on the metal mask layer;

[0079] Step S15: performing exposure processing or embossing processing;

[0080] Step S16: performing a development process or etching a residual adhesive process;

[0081] Step S17: etching the metal mask layer;

[0082] Step S18: removing the photoresist glue or the embossing glue;

[0083] Step S19: etching the inorganic transparent thin film with a high refractive index;

[0084] Step S110 : removing the metal mask layer, thereby forming an out-coupling etched grating region 22 and a turning etched grating region 21 on the substrate 10 .

[0085] In the above-mentioned embossing process, the following steps are included:

[0086] Step S21: coating a whole layer of high refractive index imprint glue on the surface of one side of the substrate 10 having the out-coupling etched grating region 22 and the turning etched grating region 21;

[0087] Step S22: aligning the sub-plate with the structural shape with the embossing glue;

[0088] Step S23: performing an imprinting process and a curing process;

[0089] Step S24 : performing demoulding treatment on the daughter plate, thereby forming an embossed layer having an in-coupled embossed grating region 41 .

[0090] Obviously, the embodiments described above are only some embodiments of the utility model, not all embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0091] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0092] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0093] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A diffractive optical waveguide, characterized in that: include: Base (10); An out-coupling etched grating region (22), wherein the out-coupling etched grating region (22) is arranged on the substrate (10); An imprinted layer, wherein the imprinted layer and the out-coupling etched grating region (22) are located on the same side surface of the substrate (10), and the out-coupling etched grating region (22) is filled and covered by the imprinted layer, and a side surface of the imprinted layer away from the substrate (10) has an in-coupling imprinted grating region (41), and an angle between the grating of the out-coupling etched grating region (22) and the substrate (10) is different from an angle between the grating of the in-coupling imprinted grating region (41) and the substrate (10).

2. The diffractive optical waveguide according to claim 1, characterized in that: The imprinted layer comprises a first imprinted layer (31) and a second imprinted layer (32) along a direction parallel to the substrate (10); a surface of the first imprinted layer (31) on a side away from the substrate (10) has the coupling-in imprinted grating region (41); the second imprinted layer (32) fills and covers the coupling-out etched grating region (22); and the thicknesses of the first imprinted layer (31) and the second imprinted layer (32) are the same or different.

3. The diffractive optical waveguide according to claim 1, characterized in that: The projection of the coupled-in imprinted grating area (41) on the substrate (10) is arranged at an interval with the projection of the coupled-out etched grating area (22) on the substrate (10), the grating of the coupled-out etched grating area (22) is arranged perpendicular to the substrate (10), and the grating of the coupled-in imprinted grating area (41) is arranged obliquely to the substrate (10).

4. The diffractive optical waveguide according to claim 1, characterized in that: The distance between the coupling-in imprinted grating region (41) and the substrate (10) is greater than the height of the coupling-out etched grating region (22).

5. The diffractive optical waveguide according to claim 2, characterized in that: The distance between a surface of the second imprinted layer (32) away from the substrate (10) and a surface of the out-coupling etched grating region (22) away from the substrate (10) is greater than 0 nm and less than or equal to 1000 nm; and / or The thickness of the first embossing layer (31) is greater than 0 nm and less than or equal to 1000 nm.

6. The diffractive optical waveguide according to claim 1, characterized in that: The surface of the embossed layer on one side away from the substrate (10) also has an out-coupling embossed grating region (43), and the out-coupling embossed grating region (43) corresponds to the out-coupling etched grating region (22).

7. The diffractive optical waveguide according to claim 6, characterized in that: The distance between the out-coupling imprinted grating region (43) and the substrate (10) is equal to the distance between the in-coupling imprinted grating region (41) and the substrate (10), and the projection of the out-coupling imprinted grating region (43) on the out-coupling etched grating region (22) at least partially covers the out-coupling etched grating region (22).

8. The diffractive optical waveguide according to claim 1, characterized in that: The out-coupling etched grating region (22) is a one-dimensional grating or a two-dimensional grating. When the out-coupling etched grating region (22) is a one-dimensional grating, the diffraction optical waveguide further comprises a turning etched grating region (21), the turning etched grating region (21) and the out-coupling etched grating region (22) are arranged on a side surface of the substrate (10) with an interval, and the turning etched grating region (21) is filled and coated by the embossed layer, and the grating of the turning etched grating region (21) is arranged perpendicular to the substrate (10).

9. The diffractive optical waveguide according to claim 8, characterized in that: The surface of the embossed layer on one side away from the substrate (10) further comprises a turning embossed grating region (42) and an out-coupling embossed grating region (43); the turning embossed grating region (42) corresponds to the turning etched grating region (21), and the out-coupling embossed grating region (43) corresponds to the out-coupling etched grating region (22).

10. The diffractive optical waveguide according to any one of claims 1 to 7, characterized in that: The refractive indexes of the turning etched grating region (21) and the out-coupling etched grating region (22) are both greater than or equal to 2.0 and less than or equal to 2.4; and / or The refractive indexes of the coupling-in imprinted grating region (41), the transition imprinted grating region (42) and the coupling-out imprinted grating region (43) are all greater than or equal to 1.5 and less than or equal to 2.0; and / or The out-coupling etched grating region (22) comprises one of a TiO2 grating, a SiO2 grating, a ZrO2 grating, a SiN grating and a SiC grating, and the in-coupling imprinted grating region (41) comprises an imprinted glue structure.

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