WO2024051257A1

WO2024051257A1 - Optical waveguide sheet and manufacturing method therefor, and augmented reality device

Info

Publication number: WO2024051257A1
Application number: PCT/CN2023/100689
Authority: WO
Inventors: 叶万俊
Original assignee: Oppo广东移动通信有限公司
Priority date: 2022-09-08
Filing date: 2023-06-16
Publication date: 2024-03-14
Also published as: CN117724200A

Abstract

The present application provides an optical waveguide sheet and a manufacturing method therefor, and an augmented reality device. The optical waveguide sheet comprises: a light conduction portion, the light conduction portion comprising a first conduction layer, a second conduction layer, and a third conduction layer which are sequentially stacked, wherein the refractive index of the first conduction layer is greater than that of the second conduction layer, and the refractive index of the third conduction layer is greater than that of the second conduction layer; and a grating portion, the grating portion comprising a light in-coupling portion and a light out-coupling portion, and the light in-coupling portion and the light out-coupling portion being spaced apart on the surface of the first conduction layer facing away from the second conduction layer. Diffraction patterns of the optical waveguide sheet of the present application have better uniformity, so that a better display effect is achieved.

Description

Optical waveguide plate, preparation method thereof and augmented reality device

Technical field

The present application relates to the field of electronics, and specifically to an optical waveguide plate, its preparation method and an augmented reality device.

Background technique

Augmented reality (AR) technology can combine virtuality and reality, and is currently being used more and more widely. In diffractive optical waveguides, light of different wavelengths and different fields of view often have different diffraction angles. This diffraction angle is generally the propagation angle of light in the optical waveguide. The greater the diffraction angle, the greater the propagation distance of light in the optical waveguide within one cycle, and the corresponding exit pupil density will be smaller. In a single-layer optical waveguide, different propagation angles correspond to different exit pupil densities of light and different grating action times. This results in a difference in energy of the final emitted light, which affects the uniformity of efficiency and color distribution within the field of view of the optical waveguide. And as the field of view increases, this difference will become more obvious, and efficiency uniformity and color distribution will be further degraded.

Contents of the invention

The first embodiment of the present application provides an optical waveguide plate, which includes:

The light conductive part includes a first conductive layer, a second conductive layer and a third conductive layer that are stacked in sequence; the refractive index of the first conductive layer is greater than the refractive index of the second conductive layer, and The refractive index of the third conductive layer is greater than the refractive index of the second conductive layer; and

The grating part includes a light coupling part and a light coupling part, and the light coupling part and the light coupling part are spaced apart on the surface of the first conductive layer facing away from the second conductive layer.

A second embodiment of the present application provides a method for preparing an optical waveguide sheet. The optical waveguide sheet includes a light conductive part and a grating part. The light conductive part includes a first conductive layer and a second conductive layer that are stacked in sequence. and a third conductive layer, the refractive index of the first conductive layer is greater than the refractive index of the second conductive layer, and the refractive index of the third conductive layer is greater than the refractive index of the second conductive layer; the grating The method includes:

Using the first molding method to form the first conductive layer and the grating part;

using a second forming method to form the second conductive layer; and

The third conductive layer is formed using a first molding method; wherein the first molding method is injection molding or pouring molding, the second molding method is injection molding or pouring molding, and the first molding method is the same as the second molding method. The molding methods are different.

A third embodiment of the present application provides an augmented reality device, which is characterized by including:

A projection light engine, the projection light engine is used to project light signals, the light signals include image information; and

The optical waveguide sheet described in the embodiment of the present application is used to transmit the optical signal.

Description of the drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without exerting creative efforts.

FIG. 1 is a schematic top structural view of an optical waveguide plate according to an embodiment of the present application.

FIG. 2 is a schematic cross-sectional structural view of the optical waveguide plate along the direction AA in FIG. 1 according to an embodiment of the present application.

Figure 3 is a schematic diagram of an optical path of an optical waveguide plate according to an embodiment of the present application.

Figure 4 is a schematic flow chart of a method for manufacturing an optical waveguide plate according to an embodiment of the present application.

Figure 5 is a schematic flow chart of a method for manufacturing an optical waveguide plate according to another embodiment of the present application.

Figure 6 is a schematic structural diagram of the first mold according to an embodiment of the present application.

FIG. 7 is a schematic structural diagram of a manufacturing process of an optical waveguide plate according to an embodiment of the present application.

Figure 8 is a schematic flow chart of a method for manufacturing an optical waveguide plate according to another embodiment of the present application.

Figure 9 is a schematic flow chart of a method for manufacturing an optical waveguide plate according to another embodiment of the present application.

FIG. 10 is a schematic structural diagram of the preparation process of the first conductive layer and the grating part according to an embodiment of the present application.

FIG. 11 is a schematic structural diagram of the third conductive layer preparation process according to an embodiment of the present application.

FIG. 12 is a schematic structural diagram of the second conductive layer preparation process according to an embodiment of the present application.

Figure 13 is a schematic structural diagram of an augmented reality device according to an embodiment of the present application.

Figure 14 is a schematic cross-sectional structural diagram of the augmented reality device along the C-C direction in Figure 13 according to an embodiment of the present application.

Figure 15 is a circuit block diagram of an augmented reality device according to an embodiment of the present application.

Explanation of reference symbols:
100-Optical waveguide plate, 10-Light conductive part, 11-First conductive layer, 13-Second conductive layer, 15-Third conductive layer, 30-
Grating part, 31-light coupling part, 33-light coupling part, 100a-first mold, 10a-first sub-mold, 11a-grating texture, 111a-coupling grating texture, 113a-coupling grating texture, 30a- Second sub-mold, 301a-first mold cavity, 100b-second mold, 101b-second mold cavity, 103b-groove, 500-augmented reality equipment, 510-projection machine, 511-display, 513-lens, 530-wearing component, 531-first wearing component, 533-second wearing component, 550-carrying component, 540-processor, 560-memory.

Detailed ways

In a first aspect, this application provides an optical waveguide plate, which includes:

Optionally, the first conductive layer, the second conductive layer, the third conductive layer and the grating part are an integral structure.

Optionally, along the stacking direction of the first conductive layer, the second conductive layer and the third conductive layer, the thickness of the first conductive layer is greater than the thickness of the second conductive layer, and the The thickness of the third conductive layer is greater than the thickness of the second conductive layer.

Optionally, along the stacking direction of the first conductive layer, the second conductive layer and the third conductive layer, the thickness h ₁ of the first conductive layer and the thickness h of the second conductive layer The range of the ratio h ₁ /h ₂ of ₂ is 7:1 ≤ _{h 1} / h ₂ ≤ 10:1; the ratio h 3 of the thickness h ₃ of the third conductive layer and the thickness h ₂ of the second conductive _layer The range of /h ₂ is 10≤h ₃ /h ₂ ≤14:1.

Optionally, along the stacking direction of the first conductive layer, the second conductive layer and the third conductive layer, the thickness h1 of the first conductive layer ranges from 0.2mm≤h1≤3mm, so The thickness h2 of the second conductive layer is in the range of 0.01mm≤h2≤0.1mm, and the thickness h3 of the third conductive layer is in the range of 0.2mm≤h3≤3mm.

Optionally, the refractive index n ₁ of the first conductive layer is equal to the refractive index n ₃ of the third conductive layer.

Optionally, the optical waveguide plate satisfies the following relationship:

2(h ₁ +h ₃ )tanθ ₁ =2h ₃ ×tanθ ₂ ; and

θ ₂ ≥sin ^-1 (n ₂ /n ₁ );

Among them, n ₂ is the refractive index of the first conductive layer, θ ₁ is when the light conductive part is a single layer, the thickness h=h ₁ + h ₃ and the refractive index n ₁ , the light is vertically incident on the optical waveguide sheet, The diffraction angle in the single-layer light transmission part; θ ₂ is the diffraction angle of light in the optical waveguide plate.

Optionally, the refractive index n1 of the first conductive layer is in the range of 1.55≤n1≤2.0; the refractive index n2 of the second conductive layer is in the range of 1.35≤n2≤1.6; the refractive index of the third conductive layer is The range of rate n3 is 1.55≤n3≤2.0.

Optionally, the first conductive layer and the third conductive layer are both thermosetting resin layers, and the second conductive layer is a thermoplastic resin layer; or, the first conductive layer and the third conductive layer are both thermosetting resin layers. is a thermoplastic resin layer, and the second conductive layer is a thermosetting resin layer.

Optionally, the thermoplastic resin layer includes polycarbonate.

In a second aspect, the present application provides a method for preparing an optical waveguide sheet. The optical waveguide sheet includes a light conductive part and a grating part. The light conductive part includes a first conductive layer, a second conductive layer and a third conductive layer that are stacked in sequence. Three conductive layers, the refractive index of the first conductive layer is greater than the refractive index of the second conductive layer, and the refractive index of the third conductive layer is greater than the refractive index of the second conductive layer; the grating portion is provided On the surface of the first conductive layer facing away from the second conductive layer; the method includes:

using a second forming method to form the second conductive layer; and

Optionally, the first molding method is casting molding, the second molding method is injection molding, and the method includes:

A first mold is provided. The first mold includes a first sub-mold and a second sub-mold. The first sub-mold and the second sub-mold enclose a first mold cavity. The first sub-mold has a surface facing the The grating texture of the first mold cavity, the grating texture is complementary to the structure of the grating part;

Inject a first thermosetting resin glue into the first mold cavity;

Solidify the first thermosetting resin glue to obtain a first conductive layer and a grating part;

A second conductive layer is formed by injection molding on the surface of the first conductive layer facing away from the grating part;

Inject a second thermosetting resin glue into the surface of the second conductive layer facing away from the first conductive layer; and

The second thermosetting resin glue is solidified to obtain a third conductive layer.

Optionally, the first thermosetting resin glue is cured to obtain a first conductive layer and a grating part, including:

Along the direction of gravity, the first sub-mold is positioned below the second sub-mold, and the first thermosetting resin glue is solidified to obtain the first conductive layer and the grating portion.

Optionally, after the first thermosetting resin glue is cured to obtain the first conductive layer and the grating part, the second conductive layer is formed by injection molding on the surface of the first conductive layer facing away from the grating part. Previously, the method also included:

The surface of the first conductive layer facing away from the grating portion is polished so that the first conductive layer faces away from the light grating portion. The surface accuracy PV1 of the gate surface is PV1≤15nm;

After the second thermosetting resin glue is cured to obtain the third conductive layer, the method further includes:

The surface of the third conductive layer facing away from the second conductive layer is polished so that the surface precision PV2 of the surface of the third conductive layer facing away from the second conductive layer is PV2≤15 nm.

Optionally, the second conductive layer is a thermoplastic resin layer, and the thermoplastic resin layer includes polycarbonate; the first thermosetting resin glue and the second thermosetting resin glue both include thermosetting resin monomers and cured Agent, the thermosetting resin monomer includes propylene carbonate, allyl diglycol carbonate, acrylonitrile, ethylene glycol dimethacrylate, allyl ester, diallyl phthalate, urethane At least one of them, the curing agent includes at least one of tert-butyl peroxyneodecanoate, isophorone diamine, ethylene diamine, and methylene biscyclohexanamine.

Optionally, the first molding method is injection molding, and the second molding method is cast molding; the method includes:

Using an injection molding method to prepare the first conductive layer and the grating part of an integrated structure, and to prepare the third conductive layer;

Arrange the first conductive layer and the third conductive layer at intervals in the second mold, with the grating portion facing away from the third conductive layer;

Inject a third thermosetting resin glue into the gap between the first conductive layer and the third conductive layer;

The third thermosetting resin glue is cured to obtain a second conductive layer.

Optionally, the second mold has a connected second mold cavity and a groove, the groove is arranged around the outer periphery of the second mold cavity, and the first conductive layer and the third mold cavity are connected to each other. The conductive layer is spaced in the second mold and includes:

Arrange the first conductive layer and the third conductive layer at intervals in the second mold cavity, and connect the gap between the first conductive layer and the third conductive layer to the groove;

Injecting a third thermosetting resin glue solution between the first conductive layer and the third conductive layer includes:

A third thermosetting resin glue is injected into the gap and the groove between the first conductive layer and the third conductive layer.

Optionally, arranging the first conductive layer and the third conductive layer in the second mold at intervals includes:

The first conductive layer and the third conductive layer are spaced apart from each other in the second mold, so that the width of the gap between the first conductive layer and the third conductive layer is 0.01 mm to 0.1 mm.

Optionally, the first conductive layer and the third conductive layer are both thermoplastic resin layers, and the thermoplastic resin layer includes polycarbonate; the third thermosetting resin glue includes a thermosetting resin monomer and a curing agent, The thermosetting resin monomer includes propylene carbonate, allyl diglycol carbonate, acrylonitrile, ethylene glycol dimethacrylate, allyl ester, diallyl phthalate, and urethane. At least one, the curing agent includes at least one of tert-butyl peroxyneodecanoate, isophorone diamine, ethylene diamine, and methylene biscyclohexanamine.

In a third aspect, this application provides an augmented reality device, which includes:

The optical waveguide plate according to the first aspect of this application is used to transmit the optical signal.

In order to enable those in the technical field to better understand the solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only These are part of the embodiments of this application, but not all of them. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

The terms "first", "second", etc. in the description and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than describing a specific sequence. Furthermore, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes Other steps or units inherent to such processes, methods, products or devices.

The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings. It should be noted that, for convenience of description, in the embodiments of the present application, the same reference numerals represent the same components, and for the sake of simplicity, detailed descriptions of the same components in different embodiments are omitted.

Augmented reality (AR) is a technology that provides users with enhanced reality perception by superimposing computer-generated image input onto real-world images and inputting it to the human eye. It is currently being used more and more widely. Optical waveguide is a media device that guides light waves to propagate in it. As the current main technical solution for augmented reality AR glasses, optical waveguides can guide the light projected by a micro projector to the front of the glasses, superimposing a virtual image on top of the real image in front of the human eye, which has the function of augmented reality. In diffractive optical waveguides, light of different wavelengths and different fields of view often have different diffraction angles. This diffraction angle is generally the propagation angle of light in the optical waveguide. The greater the diffraction angle, the greater the propagation distance of light in the optical waveguide within one cycle, and the corresponding exit pupil density will be smaller. In a single-layer optical waveguide, different propagation angles correspond to different exit pupil densities of light and different grating action times. This results in a difference in energy of the final emitted light, which affects the uniformity of efficiency and color distribution within the field of view of the optical waveguide. And as the field of view increases, this difference will become more obvious, and efficiency uniformity and color distribution will be further degraded.

Referring to FIG. 1 and FIG. 2 , an embodiment of the present application provides an optical waveguide plate 100 , which includes a light conductive part 10 and a grating part 30 . The light conductive part 10 includes a first conductive layer 11, a second conductive layer 13 and a third conductive layer 15 that are stacked in sequence. The refractive index of the first conductive layer 11 is greater than the refractive index of the second conductive layer 13. , and the refractive index of the third conductive layer 15 is greater than the refractive index of the second conductive layer 13 . The grating part 30 includes a light coupling part 31 and a light coupling part 33 . The light coupling part 31 and the light coupling part 33 are spaced apart from the first conductive layer 11 away from the second conductive layer 13 . surface.

Optionally, the light coupling part 31 is a coupling grating, and the light coupling part 33 is a coupling grating. The optical coupling part 31 is used to receive the optical signal entering the optical waveguide 100 and couple the optical signal into the optical conductive part 10 (ie, the first conductive layer 11, the second conductive layer 13 and the third conductive layer 15 ), the first conductive layer 11, the second conductive layer 13 and the third conductive layer 15 are used to transmit the optical signal; the optical coupling part 33 is used to receive the first conductive layer 11, the second conductive layer 11 and the third conductive layer 15. The optical signals transmitted by the conductive layer 13 and the third conductive layer 15 couple the optical signals out of the optical waveguide 100 .

As shown in FIG. 3 , during use, light is incident from the side of the first conductive layer 11 away from the second conductive layer 13 . When light perpendicularly enters the light transmission part 10, total reflection of the light will not occur between the first transmission layer 11 and the second transmission layer 13, and between the third transmission layer 15 and the second transmission layer 13. The light can pass through the first transmission layer 10. Propagation occurs between the conductive layer 11 and the third conductive layer 15 . When light is incident at a certain angle such as θ, total reflection occurs between the first conductive layer 11 and the second conductive layer 13 , and the light can only propagate within the first conductive layer 11 . After the incident light enters the light transmission part 10, it is transmitted through two paths, thereby improving the uniformity of the color pattern of the optical waveguide sheet 100 and improving the light efficiency.

The optical waveguide sheet 100 in the embodiment of the present application includes a light conductive part 10. The light conductive part 10 includes a first conductive layer 11, a second conductive layer 13 and a third conductive layer 15 that are stacked in sequence; The refractive index is greater than the refractive index of the second conductive layer 13, and the refractive index of the third conductive layer 15 is greater than the refractive index of the second conductive layer 13, which makes The incident light of different fields of view or the light of different wavelengths propagates in different conductive layers in the optical waveguide sheet 100 after being diffracted by the coupling grating, so that the exit pupil density of the light of different wavelengths or the diffracted light of different fields of view can be adjusted, so that The ratio of the exit pupil density is controlled in a smaller range, which increases the degree of freedom in the design of the optical waveguide plate 100. Compared with the optical waveguide plate 100 in which the light transmission part 10 is a single layer, the uniformity and diffraction image of the optical waveguide plate 100 can be improved. Improve light efficiency.

Optionally, the first conductive layer 11 , the second conductive layer 13 , the third conductive layer 15 and the grating part 30 are an integral structure. It can be understood that the first conductive layer 11 , the second conductive layer 13 , the third conductive layer 15 and the grating part 30 are connected in sequence to form an integrated structure. It can also be understood that the first conductive layer 11 , the second conductive layer 13 , the third conductive layer 15 , the coupling grating part 30 and the coupling grating part 30 are an integral structure. The one-piece structure can omit the lamination process between each resin layer, thereby avoiding misalignment problems caused by lamination.

Optionally, the refractive index of the first conductive layer 11 is equal to the refractive index of the third conductive layer 15, compared to the case where the refractive index of the first conductive layer 11 and the third conductive layer 15 are unequal, so that the first conductive layer 11 and the third conductive layer 15 only need to be prepared using the same material and formula, which can simplify the raw material preparation process and reduce the preparation cost of the optical waveguide 100. In addition, when the refractive index of the first conductive layer 11 is the same as that of the third conductive layer 11 When the refractive index of 15 is equal, the optical waveguide plate 100 produced has better display effect.

Optionally, the refractive index n1 of the first conductive layer 11 ranges from 1.55 to 2.0. Specifically, the refractive index n1 of the first conductive layer 11 may be, but is not limited to, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2.0, etc. If the refractive index of the first conductive layer 11 is too small, the field of view (FOV) of the optical waveguide 100 produced is too small, and if the refractive index of the first conductive layer 11 is too large, it is difficult to achieve it with current resin materials and processes.

Optionally, the refractive index n2 of the second conductive layer 13 ranges from 1.35 to 1.6. Specifically, the refractive index n2 of the second conductive layer 13 may be, but is not limited to, 1.35, 1.4, 1.45, 1.5, 1.55, 1.6, etc. If the refractive index of the second conductive layer 13 is too small, it is difficult to achieve it with current resin materials and processes; if the refractive index of the second conductive layer 13 is too large, the refractive index of the second conductive layer 13 will be close to that of the first conductive layer 11 or the third conductive layer. Layer 15 is not conducive to improving the uniformity of the diffraction image of the optical waveguide plate 100.

Optionally, the refractive index n3 of the third conductive layer 15 ranges from 1.55 to 2.0. Specifically, the refractive index n3 of the third conductive layer 15 may be, but is not limited to, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2.0, etc. The refractive index of the third conductive layer 15 is too small, and the field of view (FOV) of the optical waveguide 100 is too small. The refractive index of the third conductive layer 15 is too high, which is difficult to achieve with current resin materials and processes.

Optionally, along the stacking direction of the first conductive layer 11 , the second conductive layer 13 and the third conductive layer 15 , the thickness of the first conductive layer 11 is greater than that of the second conductive layer 13 The thickness of the third conductive layer 15 is greater than the thickness of the second conductive layer 13 . This can better improve the uniformity of the diffraction pattern of the optical waveguide plate 100 .

In some embodiments, along the stacking direction of the first conductive layer 11 , the second conductive layer 13 and the third conductive layer 15 , the thickness h 1 of the first conductive layer 11 is equal to the thickness h ₁ of the third conductive layer 11 . The ratio h ₁ /h ₂ of the thickness h ₂ of the two conductive layers 13 is in the range of 7:1≤h ₁ /h ₂ ≤10:1; specifically, the thickness h _{1 of the first conductive layer 11 and the thickness h 1} of the first conductive layer 13 are in the range of 7:1≤h 1 /h 2 ≤10:1. The ratio h ₁ /h ₂ of the thickness h ₂ of the second conductive layer 13 may be, but is not limited to, 7:1, 7.5:1, 8:1, 8.5:1, 9:1, 9.5:1, or 10:1. If the ratio of the thickness h ₁ of the first conductive layer 11 to the thickness h ₂ of the second conductive layer 13 is too large or too small, the uniformity of the diffraction image will be reduced, and it is impossible to improve the uniformity of the diffraction image of the optical waveguide plate 100 . Effect.

Optionally, along the stacking direction of the first conductive layer 11 , the second conductive layer 13 and the third conductive layer 15 , the thickness h ₁ of the first conductive layer 11 ranges from 0.2 mm ≤ h ₁ ≤3mm. Specifically, the thickness of the first conductive layer 11 may be, but is not limited to, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.2mm, 1.5mm, 1.8mm, 2.0mm, 2.2mm, 2.5mm, 2.8mm, 3mm, etc. If the thickness of the first conductive layer 11 is too thick, the weight of the produced optical waveguide sheet 100 will be too heavy. If the thickness of the first conductive layer 11 is too thin, the first conductive layer 11 will be too soft and easily deformed or bent, affecting the optical waveguide. The display effect of slice 100 images.

Optionally, along the stacking direction of the first conductive layer 11 , the second conductive layer 13 and the third conductive layer 15 , the thickness h ₂ of the second conductive layer 13 ranges from 0.01 mm ≤ h ₂ ≤ 0.1mm; specifically, the thickness of the second conductive layer 13 can be, but is not limited to, 0.01mm, 0.02mm, 0.03mm, 0.04mm, 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 1.0 mm etc. The thickness of the second conductive layer 13 is too thick. When the light passes through the second conductive layer 13, the optical path changes too much, making it more difficult for the optical design to achieve the expected goals, which will affect the uniformity of the displayed image. The thickness of the second conductive layer 13 is too thin. , the structure of the light conductive part 10 is close to the structure in which the first conductive layer 11 and the third conductive layer 15 are bonded together, and the effect on improving the uniformity of the diffraction image is not good.

In some embodiments, along the stacking direction of the first conductive layer 11 , the second conductive layer 13 and the third conductive layer 15 , the thickness h ₃ of the third conductive layer is equal to the thickness h 3 of the second conductive layer 15 . The ratio h ₃ /h ₂ of the thickness h ₂ of the conductive layer is in the range of 10 ≤ _{h 3} /h ₂ ≤ 14:1; specifically, the thickness h ₃ of the third conductive layer 15 and the thickness h 3 of the second conductive layer 13 The ratio of thickness h ₂ h ₃ /h ₂ can be but is not limited to 10:1, 10.5:1, 11:1, 11.5:1, 12:1, 12.5:1, 13:1, 13.5:1, 14 :1. If the ratio h ₃ /h 2 of the thickness h ₃ of the third conductive layer 15 to the thickness h ₂ of the second conductive layer ₁₃ is too large or too small, the uniformity of the diffraction image will be reduced, and it is impossible to improve the optical waveguide plate. 100% effect on diffraction image uniformity.

Optionally, along the stacking direction of the first conductive layer 11 , the second conductive layer 13 and the third conductive layer 15 , the thickness h ₃ of the third conductive layer 15 ranges from 0.2 mm ≤ h ₃ ≤3mm. Specifically, the thickness of the third conductive layer 15 may be, but is not limited to, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.2mm, 1.5mm, 1.8 mm, 2.0mm, 2.2mm, 2.5mm, 2.8mm, 3mm, etc. If the thickness of the third conductive layer 15 is too thick, the weight of the produced optical waveguide sheet 100 will be too heavy. If the thickness of the third conductive layer 15 is too thin, the third conductive layer 15 will be too soft and easily deformed or bent, affecting the optical waveguide. The display effect of slice 100 images.

In a specific embodiment, the thickness h ₁ of the first conductive layer 11 is 0.4 mm; the thickness h ₂ of the second conductive layer is 0.05 mm; and the thickness h ₃ of the third conductive layer is 0.4 mm.

In some embodiments, the thickness of the second conductive layer 13 is much smaller than the thickness of the first conductive layer 11 and the third conductive layer 15 . Therefore, the thickness of the second conductive layer 13 can be ignored. Then the optical waveguide plate satisfies the following requirements: Relationship:

2(h ₁ +h ₃ )tanθ ₁ =2h ₃ ×tanθ ₂ ; and

θ ₂ ≥sin ^-1 (n ₂ /n ₁ );

Among them, n ₂ is the refractive index of the first conductive layer, θ ₁ is when the light conductive part is a single layer, the thickness is h ₁ + h ₃ , and the refractive index is n ₁ , and the light is vertically incident on the optical waveguide sheet, The diffraction angle in the single-layer light transmission part; θ ₂ is the diffraction angle of light in the optical waveguide plate.

When the optical waveguide plate 100 satisfies the above relational expression, the uniformity of the diffraction image of the optical waveguide plate 100 can be better improved, and the optical efficiency of the optical waveguide plate 100 can be improved.

Optionally, the first conductive layer 11, the second conductive layer 13, and the third conductive layer 15 are all resin layers. Compared with the optical waveguide plate 100 made of glass, the optical waveguide plate 100 of the present application is made of resin, is lighter in weight, has better resistance to falling, and has low manufacturing cost.

In some embodiments, the first conductive layer 11 and the third conductive layer 15 are both thermosetting resin layers, and the second conductive layer 13 is a thermoplastic resin layer. In other embodiments, the first conductive layer 11 and the third conductive layer 15 are both thermoplastic resin layers, and the second conductive layer 13 is a thermosetting resin layer. Through the alternating combination of thermosetting resin layers and thermoplastic resin layers, optical The conductive part 10 can thus prepare an integrated structure, and the flatness of the surface of each resin layer can meet the requirements of optical grade flatness.

Alternatively, the thermoplastic resin layer may include, but is not limited to, polycarbonate (PC). The thermosetting resin layer is obtained by curing the thermosetting resin glue. The thermosetting resin glue includes thermosetting resin monomers and curing agents. The thermosetting resin monomers include propylene carbonate, allyl diglycol carbonate, acrylonitrile, ethylene glycol dimethacrylate, allyl ester, and phthalate. At least one of diallyl acid, urethane, etc. The curing agent includes at least one of tert-butyl peroxide neodecanoate, isophorone diamine, ethylene diamine, methylene bicyclohexanamine, and the like. Optionally, the thermosetting resin glue also includes at least one of a release agent, an antioxidant, and the like.

Alternatively, the refractive index of the first conductive layer 11 and the third conductive layer 15 can be adjusted by adding a refractive index adjuster with a high refractive index, such as a white metal oxide, such as titanium dioxide or titanium dioxide, into the thermosetting resin layer or the thermoplastic resin layer. Zirconia, etc. By adjusting the amount of titanium dioxide or zirconium dioxide added in the first conductive layer 11 and the third conductive layer 15 (for example, the amount of titanium dioxide or zirconium dioxide added (mass content) is 0.5% to 10%, etc.), the first conductivity can be adjusted. The refractive index of layer 11 or third conductive layer 15.

The optical waveguide plate 100 in the embodiment of the present application can be prepared by the method described in the following embodiments of the present application. In addition, it can also be prepared by other methods. The preparation method of the embodiment of the present application is only one part of the optical waveguide plate 100 of the present application. One or more preparation methods should not be understood as limiting the optical waveguide plate 100 provided in the embodiments of the present application.

Referring to FIG. 4 , an embodiment of the present application provides a method for preparing an optical waveguide plate 100 . The optical waveguide plate 100 includes a light conductive part 10 and a grating part 30 . The light conductive part 10 includes a first layer arranged in a stacked manner. The conductive layer 11, the second conductive layer 13 and the third conductive layer 15, the refractive index of the first conductive layer 11 is greater than the refractive index of the second conductive layer 13, and the refractive index of the third conductive layer 15 is greater than The refractive index of the second conductive layer 13; the grating portion 30 is disposed on the surface of the first conductive layer 11 facing away from the second conductive layer 13; the method includes:

S201, use the first molding method to form the first conductive layer 11 and the grating part 30;

S202, use the second molding method to form the second conductive layer 13; and

S203, use a first molding method to form the third conductive layer 15; wherein the first molding method is injection molding or pouring molding, the second molding method is injection molding or pouring molding, and the first molding method is the same as the above. The second molding method is different.

It should be noted that there is no order between S201, S202 and S203. The order between S201, S202 and S203 can be adjusted according to the difference between the first molding method and the second molding method. In this embodiment and Figure 4 The method is illustrated in the order of S201, S202, and S203 and should not be understood as limiting the scope of protection of the present application.

Optionally, the grating part 30 includes a light coupling part 31 and a light coupling part 33 , and the light coupling part 31 and the light coupling part 33 are spaced apart on the surface of the first conductive layer 11 away from the second conductive layer 13 .

The optical waveguide 100 produced by the method for preparing the optical waveguide 100 according to the embodiment of the present application includes a light conductive part 10. The light conductive part 10 includes a first conductive layer 11, a second conductive layer 13 and a third conductive layer that are stacked in sequence. 15; The refractive index of the first conductive layer 11 is greater than the refractive index of the second conductive layer 13, and the refractive index of the third conductive layer 15 is greater than the refractive index of the second conductive layer 13, which makes different fields of view incident Light of different wavelengths or light of different wavelengths propagates in different resin layers in the optical waveguide sheet 100 after being coupled into the grating and diffracted, so that the exit pupil density of light of different wavelengths or diffracted light of different fields of view can be adjusted, so that the exit pupil density can be adjusted. Controlling the ratio in a smaller range increases the degree of freedom in the design of the optical waveguide plate 100. Compared with the optical waveguide plate 100 in which the light transmission part 10 is a single layer, the uniformity of the diffraction image of the optical waveguide plate 100 can be improved and the optical efficiency can be improved. In addition, the optical waveguide plate 100 of the present application is made of resin, is lighter in weight, and has better resistance to falling. power and low preparation cost. The first conductive layer 11, the second conductive layer 13, the third conductive layer 15 and the grating part 30 of the optical waveguide sheet 100 produced in this application have an integrated structure. The first conductive layer 11, the second conductive layer 13 and the third conductive layer There is no need to laminate two layers 15, which eliminates the lamination process and can also avoid misalignment caused by the lamination process. Furthermore, the preparation method of the present application alternates injection molding and pouring molding processes, so that the surfaces of the first conductive layer 11 , the second conductive layer 13 and the third conductive layer 15 can all achieve optical-level flatness. .

Referring to Figures 5 to 7, the first molding method is casting molding, and the second molding method is injection molding. The method for preparing the optical waveguide sheet 100 provided in the embodiment of the present application includes:

S301, as shown in Figure 6, provide a first mold 100a. The first mold 100a includes a first sub-mold 10a and a second sub-mold 30a. The first sub-mold 10a and the second sub-mold 30a are enclosed together. The first mold cavity 301a, the first sub-mold 10a has a grating texture 11a facing the first mold cavity 301a, the grating texture 11a is complementary to the structure of the grating part 30. The term "structurally complementary" in this application means that when two structurally complementary components are fitted together, the protrusions of one component exactly fill the grooves of the other component and are arranged in close contact with each other.

It can be understood that the surface of the second sub-mold 30a has the grating texture 11a, and the surface of the second sub-mold 30a has the grating texture 11a and the first sub-mold 10a enclose the first mold cavity 301a. Optionally, the grating texture 11a includes a coupling grating texture 111a and a coupling grating texture 113a. The coupling grating texture 111a is complementary to the structure of the light coupling part 31, and the coupling grating texture 113a is complementary to the structure of the light coupling part 33.

S302, inject the first thermosetting resin glue into the first mold cavity 301a;

Optionally, the first thermosetting resin glue may include a thermosetting resin monomer and a curing agent. The thermosetting resin monomer includes propylene carbonate, allyl diglycol carbonate, acrylonitrile, and ethylene glycol dimethacrylic acid. At least one of ester, allyl ester, diallyl phthalate, urethane, etc. The curing agent includes at least one of tert-butyl peroxide neodecanoate, isophorone diamine, ethylene diamine, methylene bicyclohexanamine, and the like. Optionally, the first thermosetting resin glue further includes at least one of a release agent, an antioxidant, and the like. Optionally, the first thermosetting resin glue further includes a refractive index adjuster, and the refractive index adjuster includes at least one of titanium dioxide or zirconium dioxide, so that the first conductive layer 11 has a higher refractive index.

Optionally, after the thermosetting resin monomer, curing agent, release agent, antioxidant, refractive index adjuster, etc. are stirred evenly, vacuum degassing is performed under vacuum conditions to remove dissolved air in the material, and degassing is completed. Backup.

In a specific embodiment, the first thermosetting resin glue solution is prepared through the following steps: weigh 10g propylene carbonate, 5g allyl diglycol carbonate, 4.8g urethane, and 0.5g isophorone respectively. Diamine, 0.3g methylene biscyclohexylamine, 0.01g glyceryl monooleate, 0.01g di-tert-butyl-p-cresol, stir and mix evenly; defoaming under 100Pa vacuum conditions for 20 minutes.

S303, solidify the first thermosetting resin glue to obtain the first conductive layer 11 and the grating portion 30;

Optionally, the first thermosetting resin glue liquid is heated (for example, heated to 70°C to 120°C) to cause a polymerization reaction between the thermosetting resin monomer and the curing agent to form a thermosetting resin layer, that is, the first part of the integrated structure. Conductive layer 11 and grating portion 30 .

In a specific embodiment, the first thermosetting resin glue solution is gradually heated from room temperature to 80°C in 4 hours; the temperature is maintained at 80°C for 5 hours; and the first thermosetting resin glue solution is gradually heated from 80°C to 100°C in 3 hours; In 2 hours, gradually heat the first thermosetting resin glue solution from 100°C to 120°C; keep it at 120°C for 7 hours; and in 2 hours, gradually lower the temperature to 50°C.

Optionally, before the first thermosetting resin glue is heated and solidified, the first sub-mold 10a is positioned below the second sub-mold 30a in the direction of gravity, and the first thermosetting resin glue is solidified, so as to Obtain the first conductive layer 11 and grating part 30. When the thermosetting resin glue undergoes a polymerization reaction and solidifies, volume shrinkage occurs, so that the first sub-mold 10a with the grating texture 11a is located under the gravity of the second sub-mold 30a without the grating texture 11a. This can better obtain the The grating part 30 with the preset structure will not cause any error between the grating texture 11a and the preset structure due to volume shrinkage.

S304, injection molding to form a second conductive layer 13 on the surface of the first conductive layer 11 away from the grating part 30;

Alternatively, thermoplastic resin such as polycarbonate is used to form the second conductive layer 13 on the surface of the first conductive layer 11 away from the grating part 30 by high-pressure injection molding. The temperature during injection molding of polycarbonate is around 250°C, which is far lower than the softening or deformation temperature of the thermosetting resin layer. Therefore, when the second conductive layer 13 is injected, the first conductive layer 11 can still maintain its original shape. Film layer structure, surface flatness will not be affected by injection molding. In this embodiment, the reason why the second conductive layer 13 is not prepared by casting is because the raw material for casting is thermosetting resin glue. During the polymerization reaction of the thermosetting resin glue, volume shrinkage will occur, so that the obtained The surface of the second conductive layer 13 is uneven and needs to be polished to achieve optical flatness. The thickness of the second conductive layer 13 itself is only 0.01mm to 0.1mm. Therefore, it is very easy to be consumed during the polishing process, making it difficult to control the second conductive layer 13 . The thickness of the conductive layer 13. Therefore, high-pressure injection molding is required to ensure that the surface of the second conductive layer 13 away from the first conductive layer 11 can maintain optical-level flatness without polishing.

S305, inject a second thermosetting resin glue into the surface of the second conductive layer 13 facing away from the first conductive layer 11; and

Optionally, the second thermosetting resin glue may include a thermosetting resin monomer and a curing agent. The thermosetting resin monomer includes propylene carbonate, allyl diglycol carbonate, acrylonitrile, and ethylene glycol dimethacrylic acid. At least one of ester, allyl ester, diallyl phthalate, urethane, etc. The curing agent includes at least one of tert-butyl peroxide neodecanoate, isophorone diamine, ethylene diamine, methylene bicyclohexanamine, and the like. Optionally, the second thermosetting resin glue further includes at least one of a release agent, an antioxidant, and the like. Optionally, the second thermosetting resin glue further includes at least one of titanium dioxide or zirconium dioxide, so that the third conductive layer 15 has a higher refractive index.

For detailed description of other aspects of the second thermosetting resin glue, please refer to the description of the first thermoplastic resin in the above embodiments, which will not be described again here.

S306: Solidify the second thermosetting resin glue to obtain the third conductive layer 15.

Optionally, the second thermosetting resin glue liquid is heated (for example, heated to 70° C. to 120° C.) to cause a polymerization reaction between the thermosetting resin monomer and the curing agent to form a thermosetting resin layer, that is, the third conductive layer 15 .

The curing temperature of the thermosetting resin glue is generally between 70°C and 120°C, which is much lower than the second conductive layer 13 (its melting temperature is generally higher than 200°C). Therefore, during the solidification process of the second thermosetting resin glue, The second conductive layer 13 will not soften or deform, and can well maintain the flatness of the surface of the second conductive layer 13 .

It should be noted that the first conductive layer 11 , the second conductive layer 13 and the third conductive layer 15 cannot all be prepared by injection molding. Therefore, when the second conductive layer 13 is injected on the first conductive layer 11, since the injection temperature is above the melting temperature of the thermoplastic resin, if the second conductive layer 13 is injected on the surface of the first conductive layer 11, the molten thermoplastic resin will contact After reaching the first conductive layer 11, the surface of the first conductive layer 11 will soften, so that the flatness of the contact surface between the first conductive layer 11 and the second conductive layer 13 cannot be maintained. The interface between the layers 13 changes and the optical level flatness is no longer maintained. Even the resin between the first conductive layer 11 and the second conductive layer 13 will melt to a certain extent, which cannot meet the optical requirements. The second conductive layer 13 in this embodiment is a thermosetting resin layer. The temperature when the second conductive layer 13 is formed is relatively low, so the interface between the first conductive layer 11 and the second conductive layer 13 will not change. ization and can maintain good optical grade flatness.

Please refer to Figure 8. The first molding method is casting molding, and the second molding method is injection molding. The method for preparing the optical waveguide sheet 100 provided in the embodiment of the present application includes:

S401. Provide a first mold 100a. The first mold 100a includes a first sub-mold 10a and a second sub-mold 30a. The first sub-mold 10a and the second sub-mold 30a enclose a first mold cavity 301a. The first sub-mold 10a has a grating texture 11a facing the first mold cavity 301a, and the grating texture 11a is complementary to the structure of the grating part 30;

S402, inject the first thermosetting resin glue into the first mold cavity 301a;

S403, position the first sub-mold 10a below the second sub-mold 30a along the direction of gravity, and solidify the first thermosetting resin glue to obtain the first conductive layer 11 and the grating portion 30;

For detailed descriptions of S401 to S403, please refer to the descriptions of the corresponding parts of the above embodiments, which will not be described again here.

S404, polish the surface of the first conductive layer 11 facing away from the grating part 30, so that the surface precision PV1 of the first conductive layer 11 facing away from the grating part 30 is PV1≤15nm;

The term "PV" refers to the difference between the highest and lowest value on a surface. The PV value is a measure of surface roughness.

Optionally, a polishing machine is used to polish the surface of the first conductive layer 11 facing away from the grating part 30, so that the surface accuracy PV1 of the surface of the first conductive layer 11 facing away from the grating part 30 is PV1≤ 15 nm, so that the surface of the first conductive layer 11 facing away from the grating portion 30 reaches an optical level of flatness. When the first thermally fixed resin glue undergoes a polymerization reaction to form the first conductive layer 11, the volume will shrink. Therefore, the surface of the formed first conductive layer 11 away from the grating portion 30 will be uneven. Therefore, it is necessary to conduct the first conductive layer 11. The surface of the layer 11 facing away from the grating part 30 is polished so that the surface of the first conductive layer 11 facing away from the grating part 30 can reach optical grade flatness, so that the manufactured optical waveguide plate 100 has better image display effect.

S405, injection molding to form a second conductive layer 13 on the surface of the first conductive layer 11 away from the grating part 30;

S406, inject a second thermosetting resin glue into the surface of the second conductive layer 13 facing away from the first conductive layer 11;

S407, solidify the second thermosetting resin glue to obtain the third conductive layer 15; and

For a detailed description of S405 to S407, please refer to the description of the corresponding part of the above embodiment, and details will not be described again here.

S408: Polish the surface of the third conductive layer 15 facing away from the second conductive layer 13 so that the surface precision PV2 of the surface of the third conductive layer 15 facing away from the second conductive layer 13 is PV2≤15 nm.

Optionally, a polishing machine is used to polish the surface of the third conductive layer 15 facing away from the second conductive layer 13, so that the surface precision PV1 of the surface of the third conductive layer 15 facing away from the second conductive layer 13 is PV1. ≤15 nm, so that the surface of the third conductive layer 15 facing away from the second conductive layer 13 reaches an optical level of flatness. Since the volume of the second heat-fixing resin glue polymerizes to form the third conductive layer 15, the volume will shrink. Therefore, the surface of the formed third conductive layer 15 facing away from the second conductive layer 13 will be uneven. Therefore, it is necessary to The surface of the third conductive layer 15 facing away from the second conductive layer 13 is polished so that the surface of the third conductive layer 15 facing away from the second conductive layer 13 can reach an optical level of flatness, so that the manufactured The optical waveguide plate 100 has better image display effect.

Referring to Figure 9, the first molding method is injection molding, and the second molding method is casting molding; the method for preparing the optical waveguide sheet 100 provided in the embodiment of the present application includes:

S501, use an injection molding method to prepare the first conductive layer 11 and the grating part 30 of an integrated structure, and prepare the third conductive layer 15;

As shown in Figures 10 and 11, optionally, using a thermoplastic resin such as polycarbonate, the first injection mold P and the second injection mold Q, using an injection molding method to manufacture the first conductive layer 11 and the grating part 30 of an integrated structure, and the third conductive layer 15 respectively. Since the first conductive layer 11 and the second conductive layer 13 obtained by high-pressure injection molding will not undergo significant volume shrinkage, the first conductive layer 11 and the third conductive layer 15 do not need to be polished.

Polycarbonate has a high refractive index, which allows the manufactured optical waveguide plate 100 to have a large field of view (FOV). The thermal deformation temperature of polycarbonate is relatively high, usually about 135°C, higher than 120°C. Therefore, there will be no softening phenomenon when the second conductive layer 13 is formed during pouring and solidification.

For detailed descriptions of the first conductive layer 11 , the grating portion 30 and the third conductive layer 15 , please refer to the descriptions of the corresponding parts of the above embodiments and will not be described again here.

S502, arrange the first conductive layer 11 and the third conductive layer 15 in the second mold 100b at intervals, and make the grating part 30 away from the third conductive layer 15;

Please refer to Figure 12 together. Optionally, the second mold 100b has a second mold cavity 101b. The first conductive layer 11 is installed on one side of the second mold cavity 101b of the second mold 100b, and the third conductive layer 11 is installed on one side of the second mold cavity 101b. 15 is installed in the second mold cavity 101b on the side opposite to the first conductive layer 11, so that there is a gap between the first conductive layer 11 and the second conductive layer 13, and at the same time, the first conductive layer 11 is compared with The grating portion 30 is closer to the third conductive layer 15 . In other words, the grating portion 30 is further away from the third conductive layer 15 than the first conductive layer 11 . It can be understood that after the first conductive layer 11 and the third conductive layer 15 are installed, the surface of the first conductive layer 11 facing the third conductive layer 15 is parallel to the surface of the third conductive layer 15 facing the second conductive layer 13 .

Optionally, the width of the gap between the first conductive layer 11 and the third conductive layer 15 , that is, the surface of the first conductive layer 11 facing the third conductive layer 15 and the surface of the third conductive layer 15 facing the second conductive layer 13 The vertical distance between them ranges from 0.01mm to 0.1mm. In other words, the distance between the first conductive layer 11 and the third conductive layer 15 is adjusted so that the distance between them is the thickness of the second conductive layer 13 .

In some embodiments, the second mold 100b further has a groove 103b, the groove 103b is arranged around the outer periphery of the second mold cavity 101b, and the groove 103b is connected with the second mold cavity 101b. At this time, arranging the first conductive layer 11 and the third conductive layer 15 in the second mold 100b at intervals includes arranging the first conductive layer 11 and the third conductive layer 15 in the second mold 100b at intervals. In the mold cavity 101b, the gap between the first conductive layer 11 and the third conductive layer 15 is connected to the groove 103b.

Optionally, the groove 103b is disposed at the middle position on the outer circumferential side of the second mold cavity 101b, so that the first conductive layer 11 and the third conductive layer 15 can be disposed behind the second mold cavity 101b, and the first conductive layer The gap formed between the layer 11 and the third conductive layer 15 can better align the groove 103b and communicate with the groove 103b.

S503, inject the third thermosetting resin glue into the gap between the first conductive layer 11 and the third conductive layer 15;

Optionally, the gap between the first conductive layer 11 and the third conductive layer 15 is filled with a third thermosetting resin glue.

Optionally, the third thermosetting resin glue may include a thermosetting resin monomer and a curing agent. The thermosetting resin monomer includes propylene carbonate, allyl diglycol carbonate, acrylonitrile, and ethylene glycol dimethacrylic acid. At least one of ester, allyl ester, diallyl phthalate, urethane, etc. The curing agent includes at least one of tert-butyl peroxide neodecanoate, isophorone diamine, ethylene diamine, methylene bicyclohexanamine, and the like.

Optionally, when the second mold 100b also has a groove 103b, the method further includes injecting a third thermosetting resin glue into the groove 103b. In other words, the third thermosetting resin glue is injected into the gap between the first conductive layer 11 and the third conductive layer 15 and into the groove 103b.

When the third thermosetting resin glue undergoes a polymerization reaction and solidifies, volume shrinkage occurs, and the gap between the first layer and the third layer is small. The third thermosetting resin glue is also injected into the groove 103b, so that in the third layer When the thermosetting resin glue undergoes a polymerization reaction to solidify and shrinks in volume, a certain amount of the third thermosetting resin glue (i.e., the third thermosetting resin glue in the groove 103b) can be extracted from the groove 103b through the action of capillary force. will flow into the gap between the first conductive layer 11 and the third conductive layer 15 under the action of capillary force), so that the first conductive layer 11 and the third conductive layer 15 always maintain a filled state. Undesirable phenomena such as insufficient filling or delamination occur between the conductive layer 11 and the third conductive layer 15 .

For detailed description of other aspects of the third thermosetting resin glue, please refer to the description of the first thermoplastic resin in the above embodiments, which will not be described again here.

S504, solidify the third thermosetting resin glue to obtain the second conductive layer 13.

Optionally, the third thermosetting resin glue liquid is heated (for example, heated to 70°C to 120°C) to cause a polymerization reaction between the thermosetting resin monomer and the curing agent to form a thermosetting resin layer, that is, the second conductive layer 13 .

Referring to Figures 13 and 14, an embodiment of the present application also provides an augmented reality device 500, which includes: a projection light machine 510 and the optical waveguide sheet 100 of the present application. The projection light engine 510 is used to project light signals, and the light signals include image information; the optical waveguide plate 100 is disposed on the exit surface of the projection light engine 510 and is used to transmit the light signals. It can be understood that the grating portion 30 of the optical waveguide plate 100 is arranged away from the projection light machine 510 .

Optionally, the projection light machine 510 includes a display 511 and a lens 513. The display 511 is used to emit light signals, and the lens 513 is provided on the display surface side of the display 511 to modulate the light signals, so that the light rays (light signals) of different viewing angles emitted from the same pixel point on the display 511 pass through After modulation, the lens 513 emits in the form of parallel light to place the image information in the optical signal at an infinite distance so that it can be viewed by the naked eye. The optical waveguide 100 is disposed on the side of the lens 513 away from the display 511 and is used for transmitting the optical signal modulated by the lens 513 .

The augmented reality device 500 of the present application may be, but is not limited to, near-eye display devices such as augmented reality glasses (AR glasses), augmented reality helmets, and augmented reality masks.

Alternatively, display 511 may be a microdisplay. The display 511 includes a light emitting unit, which may include, but is not limited to, a micro light emitting diode (Micro Light Emitting Diode, Micro LED) chip, a micro organic light emitting diode (Micro Organic Light-Emitting Diode, Micro OLED) chip or a micro liquid crystal display ( At least one of Micro liquid crystal display, Micro LCD). Under the same operating power conditions, the brightness of Micro OLED is usually less than 5000nits, the brightness of LCD is usually less than 15000nits, and the brightness of Micro LED can reach 2000000nits, which is much higher than the former two. Therefore, compared with Micro OLED displays and Micro LCD displays, when the display 511 is a Micro LED display, the image output by it has higher brightness. Compared with Micro LCD displays, Micro LED displays are self-illuminating light sources and have better contrast and smaller display delays when applied to the augmented reality device 500.

In some embodiments, the area on the display surface that can emit light signals becomes the effective light-emitting area. The diagonal size of the effective light-emitting area of the display 511 ranges from 0.11 inch to 0.15 inch, and the effective light-emitting area aspect ratio is 4:3. In other embodiments, the diagonal size of the effective light-emitting area of the display 511 ranges from 0.17 inch to 0.21 inch, and the effective light-emitting area aspect ratio is 16:9. Optionally, the color of the light emitted by the display 511 may be, but is not limited to, at least one of red light, green light, blue light, etc. In a specific embodiment, the display 511 is a Micro LED that emits green light. In other embodiments, it can also be another monochromatic light Micro LED or a multi-color light Micro LED.

In some embodiments, the optical waveguide 100 can also detect the image information in the optical signal emitted by the lens 513 in one dimension. Or dilate the pupil in two dimensions to increase the range of orbital movement, thereby adapting to more people.

In some embodiments, the augmented reality device 500 of the present application further includes a carrying member 550 , which is used to carry the optical waveguide sheet 100 . Optionally, the carrier 550 may be, but is not limited to, a frame of augmented reality glasses, a helmet body of an augmented reality helmet, a mask body of an augmented reality mask, etc. Alternatively, the optical waveguide sheet 100 may be disposed on the carrier 550 through adhesive or fastening parts.

In some embodiments, when the augmented reality device 500 is augmented reality glasses, the augmented reality device 500 in this embodiment of the present application further includes a wearing piece 530 . The wearing part 530 is rotatably connected to the carrying part 550, and the wearing part 530 is used to hold the wearer (such as a human head or a head prosthesis, etc.).

Optionally, the wearing part 530 includes a first wearing part 531 and a second wearing part 533. The first wearing part 531 is rotatably connected to one end of the carrying part 550, and the second wearing part 533 is rotatably connected to the carrying part. 550 is away from the other end of the first wearing component 531 . The first wearing component 531 cooperates with the second wearing component 533 to clamp the augmented reality device 500 to the wearer. Optionally, the first wearing component 531 and the second wearing component 533 are also used to set the projector.

Optionally, both the first wearing component 531 and the second wearing component 533 may be, but are not limited to, temples of the augmented reality device 500 (AR glasses).

Referring to Figure 15, the augmented reality device 500 in this embodiment of the present application also includes a processor 540 and a memory 560. The processor 540 is electrically connected to the display 511 and is used to control the display 511 to emit light signals containing image information, etc. The memory 560 is electrically connected to the processor 540 and is used to store program codes required for the operation of the processor 540, program codes required for controlling the display 511, image information emitted by the display 511, etc.

Optionally, the processor 540 includes one or more general-purpose processors, where the general-purpose processor can be any type of device capable of processing electronic instructions, including a central processing unit (Central Processing Unit, CPU), a microprocessor, a microprocessor, Controllers, main processors, controllers, ASICs, etc. The processor 540 is used to execute various types of digital storage instructions, such as software or firmware programs stored in the memory 560, which can enable the computing device to provide a wide variety of services.

Optionally, the memory 560 may include volatile memory (Volatile Memory), such as random access memory (Random Access Memory, RAM); the memory 560 may also include non-volatile memory (Non-Volatile Memory, NVM), such as Read-Only Memory (ROM), Flash Memory (FM), Hard Disk Drive (HDD) or Solid-State Drive (SSD). Memory 560 may also include a combination of the types of memory described above.

It can be understood that the augmented reality device 500 in this embodiment is only a form of the augmented reality device 500 applied to the optical waveguide sheet 100, and should not be understood as a limitation of the augmented reality device 500 provided in this application.

Reference in this application to "an embodiment" or "an implementation" means that a particular feature, structure or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of recited phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those skilled in the art understand explicitly and implicitly that the embodiments described herein may be combined with other embodiments. In addition, it should also be understood that the features, structures or characteristics described in the embodiments of the present application can be arbitrarily combined to form another structure without departing from the spirit and scope of the technical solution of the present application, provided there is no contradiction between them. embodiment.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the above preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present application can be modified. Any modification or equivalent substitution of the solution shall not depart from the spirit and scope of the technical solution of this application.

Claims

An optical waveguide sheet, characterized by including:

The light conductive part includes a first conductive layer, a second conductive layer and a third conductive layer that are stacked in sequence; the refractive index of the first conductive layer is greater than the refractive index of the second conductive layer, and The refractive index of the third conductive layer is greater than the refractive index of the second conductive layer; and

The grating part includes a light coupling part and a light coupling part, and the light coupling part and the light coupling part are spaced apart on the surface of the first conductive layer facing away from the second conductive layer.
The optical waveguide sheet according to claim 1, wherein the first conductive layer, the second conductive layer, the third conductive layer and the grating part are of an integrated structure.
The optical waveguide sheet according to claim 1, characterized in that, along the stacking direction of the first conductive layer, the second conductive layer and the third conductive layer, the thickness h of the first conductive layer 1 is greater than the thickness h 2 of the second conductive layer, and the thickness h 3 of the third conductive layer is greater than the thickness h 2 of the second conductive layer.
The optical waveguide sheet according to claim 3, characterized in that, along the stacking direction of the first conductive layer, the second conductive layer and the third conductive layer, the thickness h of the first conductive layer The ratio h 1 /h 2 of 1 to the thickness h 2 of the second conductive layer is in the range of 7:1≤h 1 /h 2 ≤10:1, and the thickness h 3 of the third conductive layer is in the range of 7:1≤h 1 /h 2 ≤10:1. The ratio h 3 /h 2 of the thickness h 2 of the two conductive layers ranges from 10 ≤ h 3 /h 2 ≤ 14:1.
The optical waveguide sheet according to claim 3, characterized in that, along the stacking direction of the first conductive layer, the second conductive layer and the third conductive layer, the thickness h1 of the first conductive layer The range of the thickness h2 of the second conductive layer is 0.2mm≤h1≤3mm, the range of the thickness h2 of the second conductive layer is 0.01mm≤h2≤0.1mm, and the range of the thickness h3 of the third conductive layer is 0.2mm≤h3≤3mm.
The optical waveguide sheet according to claim 3, wherein the refractive index n 1 of the first conductive layer is equal to the refractive index n 3 of the third conductive layer.
The optical waveguide plate according to claim 6, characterized in that the optical waveguide plate satisfies the following relational expression:
2(h 1 +h 3 )tanθ 1 =2h 3 ×tanθ 2 ; and θ 2 ≥ sin -1 (n 2 /n 1 );

Among them, n 2 is the refractive index of the first conductive layer, θ 1 is when the light conductive part is a single layer, the thickness h=h 1 + h 3 and the refractive index n 1 , the light is vertically incident on the optical waveguide sheet, The diffraction angle in the single-layer light transmission part; θ 2 is the diffraction angle of light in the optical waveguide plate.
The optical waveguide sheet according to any one of claims 1 to 7, characterized in that the refractive index n1 of the first conductive layer is in the range of 1.55≤n1≤2.0; the refractive index n2 of the second conductive layer is in the range of 1.55≤n1≤2.0. The range is 1.35≤n2≤1.6; the range of the refractive index n3 of the third conductive layer is 1.55≤n3≤2.0.
The optical waveguide sheet according to any one of claims 1 to 7, wherein the first conductive layer and the third conductive layer are both thermosetting resin layers, and the second conductive layer is a thermoplastic resin layer; Alternatively, the first conductive layer and the third conductive layer are both thermoplastic resin layers, and the second conductive layer is a thermosetting resin layer.
The optical waveguide sheet according to claim 9, wherein the thermoplastic resin layer includes polycarbonate.
A method for preparing an optical waveguide sheet, characterized in that the optical waveguide sheet includes a light conductive part and a grating part, and the light conductive part includes a first conductive layer, a second conductive layer and a third conductive layer that are stacked in sequence. , the refractive index of the first conductive layer is greater than the refractive index of the second conductive layer, and the refractive index of the third conductive layer is greater than the refractive index of the second conductive layer; the grating portion is disposed on the A surface of the first conductive layer facing away from the second conductive layer; the method includes:

Using the first molding method to form the first conductive layer and the grating part;

using a second forming method to form the second conductive layer; and

Using the first forming method to form the third conductive layer;

Wherein, the first molding method is injection molding or pouring molding, the second molding method is injection molding or pouring molding, and the first molding method is different from the second molding method.
The method for preparing an optical waveguide plate according to claim 11, wherein the first molding method is casting molding, the second molding method is injection molding, and the method includes:

A first mold is provided. The first mold includes a first sub-mold and a second sub-mold. The first sub-mold and the second sub-mold enclose a first mold cavity. The first sub-mold has a surface facing the The grating texture of the first mold cavity, the grating texture is complementary to the structure of the grating part;

Inject a first thermosetting resin glue into the first mold cavity;

Solidify the first thermosetting resin glue to obtain a first conductive layer and a grating portion;

A second conductive layer is formed by injection molding on the surface of the first conductive layer facing away from the grating part;

Inject a second thermosetting resin glue into the surface of the second conductive layer facing away from the first conductive layer; and

The second thermosetting resin glue is solidified to obtain a third conductive layer.
The method for preparing an optical waveguide plate according to claim 12, wherein the step of solidifying the first thermosetting resin glue to obtain the first conductive layer and the grating part includes:

Along the direction of gravity, the first sub-mold is positioned below the second sub-mold, and the first thermosetting resin glue is solidified to obtain the first conductive layer and the grating portion.
The method for preparing an optical waveguide according to claim 12, wherein after the first thermosetting resin glue is cured to obtain the first conductive layer and the grating portion, the first conductive layer is Before the surface of the layer facing away from the grating part is injection molded to form the second conductive layer, the method further includes:

Polish the surface of the first conductive layer facing away from the grating part so that the surface precision PV1 of the first conductive layer facing away from the grating part is PV1≤15nm;

After the second thermosetting resin glue is cured to obtain the third conductive layer, the method further includes:

The surface of the third conductive layer facing away from the second conductive layer is polished so that the surface precision PV2 of the surface of the third conductive layer facing away from the second conductive layer is PV2≤15 nm.
The method for preparing an optical waveguide sheet according to any one of claims 12 to 14, wherein the second conductive layer is a thermoplastic resin layer, and the thermoplastic resin layer includes polycarbonate; and the first thermosetting layer The resin glue liquid and the second thermosetting resin glue liquid both include thermosetting resin monomers and curing agents. The thermosetting resin monomers include propylene carbonate, allyl diglycol carbonate, acrylonitrile, and ethylene glycol dimethyl. At least one of acrylate, allyl ester, diallyl phthalate, and urethane, and the curing agent includes tert-butyl peroxyneodecanoate, isophorone diamine, and ethylene diamine. , at least one of methylene biscyclohexane amines.
The method for preparing an optical waveguide plate according to claim 11, wherein the first molding method is injection molding, and the second molding method is casting molding; the method includes:

Using an injection molding method to prepare the first conductive layer and the grating part of an integrated structure, and to prepare the third conductive layer;

Arrange the first conductive layer and the third conductive layer at intervals in the second mold, with the grating portion facing away from the third conductive layer;

Inject a third thermosetting resin glue into the gap between the first conductive layer and the third conductive layer;

The third thermosetting resin glue is cured to obtain a second conductive layer.
The method for preparing an optical waveguide according to claim 16, wherein the second mold has a connected second mold cavity and a groove, and the groove is arranged around the outer periphery of the second mold cavity, The step of arranging the first conductive layer and the third conductive layer in the second mold at intervals includes:

Arrange the first conductive layer and the third conductive layer at intervals in the second mold cavity, and connect the gap between the first conductive layer and the third conductive layer to the groove;

Injecting a third thermosetting resin glue solution between the first conductive layer and the third conductive layer includes:

A third thermosetting resin glue is injected into the gap and the groove between the first conductive layer and the third conductive layer.
The method for manufacturing an optical waveguide sheet according to claim 16, wherein the step of arranging the first conductive layer and the third conductive layer in a second mold at intervals includes:

The first conductive layer and the third conductive layer are spaced apart from each other in the second mold, so that the width of the gap between the first conductive layer and the third conductive layer is 0.01 mm to 0.1 mm.
The method for preparing an optical waveguide according to any one of claims 16 to 18, wherein the first conductive layer and the third conductive layer are both thermoplastic resin layers, and the thermoplastic resin layer includes polyethylene. Carbonate; the third thermosetting resin glue includes a thermosetting resin monomer and a curing agent. The thermosetting resin monomer includes propylene carbonate, allyl diglycol carbonate, acrylonitrile, and ethylene glycol dimethacrylic acid. At least one of ester, allyl ester, diallyl phthalate, and urethane, the curing agent includes tert-butyl peroxyneodecanoate, isophorone diamine, ethylene diamine, At least one kind of methylene biscyclohexane amine.
An augmented reality device, characterized by including:

A projection light engine, the projection light engine is used to project light signals, the light signals include image information; and

The optical waveguide plate according to any one of claims 1 to 10, said optical waveguide plate being used to transmit the optical signal.