WO2024001466A1

WO2024001466A1 - Bicolor ar diffraction waveguide and ar glasses

Info

Publication number: WO2024001466A1
Application number: PCT/CN2023/090161
Authority: WO
Inventors: 蒋厚强; 朱以胜
Original assignee: 深圳市光舟半导体技术有限公司
Priority date: 2022-06-29
Filing date: 2023-04-23
Publication date: 2024-01-04
Also published as: CN217506282U

Abstract

A bicolor AR diffraction waveguide (1) and AR glasses. The waveguide comprises: an entrance pupil area (11) located at the center of the waveguide (1); a first pupil expansion area (21) and a second pupil expansion area (22), which are symmetrically distributed on two sides of the entrance pupil area (11); a first exit pupil area (31) arranged below the first pupil expansion area (21); and a second exit pupil area (32) arranged below the second pupil expansion area (22), wherein the entrance pupil area (11), the first pupil expansion area (21) and the first exit pupil area (31) form a first channel, and the entrance pupil area (11), the second pupil expansion area (22) and the second exit pupil area (32) form a second channel; and the first channel is provided with a first band-pass filter (41), and the second channel is provided with a second band-pass filter or a cut-off filter (42). By means of providing the first band-pass filter (41) on the first channel of the waveguide (1) and providing the second band-pass filter or the cut-off filter (42) on the second channel thereof, the first channel and the second channel respectively transmit light of different colors, such that pictures of different colors are displayed on the left and right sides of the waveguide (1), thereby achieving the effect of presenting a 3D stereoscopic image on AR glasses by using a single light source.

Description

Two-color AR diffraction waveguide and AR glasses

Cross-references to related applications

This application requests the priority of the Chinese patent application with application number 2022216699904 and titled "A two-color AR diffraction waveguide and AR glasses" submitted to the State Intellectual Property Office of China on June 29, 2022, and filed on May 10, 2021. The rights and interests of the Chinese patent application submitted to the China State Intellectual Property Office with the application number 202120994213.6 and titled "A single projector 3D imaging AR glasses" were submitted to the China State Intellectual Property Office on June 11, 2021. 2021213091201, the rights and interests of the Chinese patent application titled "Waveguide plate assembly and folding AR eyepiece in front of the optical machine", and the application number 202110450358.4 submitted to the China State Intellectual Property Office on April 25, 2021, titled "A The rights and interests of the Chinese patent application "Binocular AR Eyepiece Vision Correction System", the contents of the above application are all incorporated into this application by reference.

Technical field

This application relates to the field of AR display technology, specifically to a two-color AR diffraction waveguide and AR glasses.

Background technique

At present, from the earliest 3D movies to the current IMAX giant-screen movies, to the popular AR, VR and holographic images, people have never stopped in the pursuit of 3D real experience, because 3D display can bring Better immersive experience.

In the field of interaction, 3D imaging technology is particularly critical. Through the upgrade from 2D to 3D, comprehensive three-dimensional information can be obtained, and the three-dimensional contours and physical characteristics of each object will be more fully recognized. In the AR diffraction waveguide display, dual light sources can achieve stereoscopic display by inputting left and right images to the left and right eyes; however, it is more difficult to display a 2D image to a 3D image with a single light source input. Therefore, how to display a 3D stereoscopic image through a single light source is the key point. Problems that need to be solved by those skilled in the field.

In addition, with the advancement of imaging technology, people's demand for immersive experience is getting higher and higher. In recent years, the development of VR/AR technology has gradually satisfied people's pursuit of visual experience. Head-mounted devices can free people's hands, reduce dependence on screens, and create better visual effects. For head-mounted devices, near-eye display is the key to its technology, and imaging quality and thinness are the main considerations. The near-eye display system generally consists of an image far and near light transmission system. The image screen emitted by the image source is transmitted to the human eye through the optical transmission system. Here, unlike VR, which blocks the external environment, AR requires a certain transmittance so that the wearer can see the outside environment while seeing the image.

For optical transmission systems, the industry has many solutions, such as free-space optics, free-form optics, and display optical waveguides. Among them, optical waveguide technology is significantly better than other optical solutions due to its large eye box and thin and light characteristics, and has become the mainstream path for major companies.

At present, most AR glasses products from various manufacturers use a dual-projector configuration. This configuration can control the images of the left and right eyes respectively, thereby synthesizing a visual image with a 3D effect. However, the assembly steps of dual projectors are complicated because the resulting images need to be calibrated, which is time-consuming and has low yield, which is not conducive to mass production.

Therefore, the existing technology still needs to be improved and developed.

Contents of the invention

This application provides a two-color AR diffractive waveguide and AR glasses, aiming to display different color images on the left and right sides of the waveguide, so as to achieve the effect of a single light source directly presenting a 3D stereoscopic image on the AR glasses.

Some embodiments of the present application provide a two-color AR diffraction waveguide. The two-color AR diffraction waveguide may include: an entrance pupil area located at the center of the waveguide, a first pupil expansion area and a second pupil expansion area symmetrically distributed on both sides of the entrance pupil area. a pupil expansion area, a first exit pupil area provided below the first pupil expansion area, and a second exit pupil area provided below the second pupil expansion area;

Wherein, the entrance pupil area, the first pupil expansion area and the first exit pupil area form a first channel, and the entrance pupil area, the second pupil expansion area and the second exit pupil area form a second channel; the first A first bandpass filter is provided on the channel, and a second bandpass filter or cutoff filter is provided on the second channel.

In some optional implementations according to the present application, the first bandpass filter may be disposed in the waveguide between the entrance pupil area and the first pupil expansion area, and the second bandpass filter or The cutoff filter is disposed in the waveguide between the entrance pupil area and the second pupil expansion area.

In some optional implementations according to the present application, the first bandpass filter may be disposed in the waveguide between the entrance pupil area and the first pupil expansion area, and the second bandpass filter or The cutoff filter is disposed on the waveguide surface between the entrance pupil area and the second pupil expansion area.

In some optional implementations according to the present application, the first bandpass filter may be disposed in the waveguide between the first pupil expansion area and the first exit pupil area, and the second bandpass filter A sheet or cutoff filter is disposed in the waveguide between the second pupil expansion area and the second exit pupil area.

In some optional implementations according to the present application, the first bandpass filter may be disposed in the waveguide between the first pupil expansion area and the first exit pupil area, and the second bandpass filter A sheet or cutoff filter is disposed on the waveguide surface between the second pupil expansion area and the second exit pupil area.

In some optional implementations according to the present application, the first band-pass filter is 2 to 4 mm away from the left edge of the entrance pupil area, and the second band-pass filter or cut-off filter is 2 to 4 mm away from the left edge of the entrance pupil area. The right edge of the entrance pupil area is 2 to 4 mm.

In some optional implementations according to the present application, the first band-pass filter is 1 to 2 mm away from the lowermost edge of the first pupil expansion area, and the second band-pass filter or cut-off filter is 1 to 2 mm away from the lowermost edge of the first pupil expansion area. The lowermost edge of the second pupil dilation area is 1 to 2 mm.

In some optional implementations according to the present application, the first bandpass filter may be a red bandpass filter, so that the first channel conducts red light;

The second bandpass filter is a blue bandpass filter or the cutoff filter is a red cutoff filter, so that the second channel transmits blue light or blue-green light.

In some optional implementations according to the present application, the bandwidth of the red band-pass filter may be 590-640 nm, the bandwidth of the blue band-pass filter may be 420-480 nm, and the bandwidth of the red cut-off filter may be 590-640 nm. The cut-off band is 590~640nm.

In some optional implementations according to the present application, the length of the waveguide in the y-axis direction may be 100-120 mm, the width in the x-axis direction may be 35-50 mm, and the thickness may be 0.5-1 mm;

The diameter of the entrance pupil area may be 4-6 mm; the length of the first exit pupil area and the second exit pupil area are both 30-40 mm, and the width is 20-30 mm; the first pupil expansion area and the second exit pupil area The width of the two dilated pupil areas is 2 to 5 times the diameter of the entrance pupil area, and the side width close to the entrance pupil area is 2 to 3 times the diameter of the entrance pupil area, and the width far from the entrance pupil area is 2 to 3 times the diameter of the entrance pupil area. The side width is 3 to 5 times the diameter of the entrance pupil area, and the length is 1.5 to 2 times the length of the first exit pupil area or the second exit pupil area;

The length of the first band-pass filter and the second band-pass filter or cut-off filter may be less than 0.5 mm, and the width may be 6 to 10 mm. Larger than the diameter of the entrance pupil area, the thickness is the same as the thickness of the waveguide.

In some optional implementations according to the present application, the waveguide may be an integrated butterfly waveguide for left and right eyes;

The entrance pupil area, the first pupil expansion area, the second pupil expansion area, the first exit pupil area and the second exit pupil area may all adopt diffraction gratings, and the diffraction gratings are surface relief gratings or volume holographic gratings.

In some optional implementations according to the present application, the diffraction grating may correspond to an entrance pupil grating unit, a pupil expansion grating unit and an exit pupil grating unit.

In some optional embodiments according to the present application, the waveguide may further include a waveguide plate assembly. The waveguide plate assembly includes a left waveguide plate and a right waveguide plate that are connected to each other. With the connection as the center, the left waveguide plate assembly The structures of the waveguide plate and the right waveguide plate are mirror symmetrical, and both include: an entrance pupil grating unit, a pupil expansion grating unit and an exit pupil grating unit.

In some optional implementations according to the present application, the left waveguide plate and the right waveguide plate may form an obtuse angle at the connection point, with the inside of the obtuse angle being the inner side of the waveguide plate assembly, and the outside of the obtuse angle being the The outside of the waveguide assembly; the input light of the waveguide assembly is injected into the entrance pupil grating unit from the outside, passes through the pupil expansion grating unit, and is emitted from the exit pupil grating unit, and the exit pupil grating unit emits light The direction is consistent with the direction of incident light of the entrance pupil grating unit.

Embodiments of the present application also provide AR glasses, which can use the two-color AR diffraction waveguide as described in any one of the above.

The two-color AR diffraction waveguide according to the embodiment of the present application includes: an entrance pupil area located in the center of the waveguide, a first pupil expansion area and a second pupil expansion area symmetrically distributed on both sides of the entrance pupil area, a first exit pupil area below the pupil expansion area and a second exit pupil area provided below the second pupil expansion area; wherein the entrance pupil area, the first pupil expansion area and the first exit pupil area form a first channel, the entrance pupil area, the second pupil expansion area and the second exit pupil area form a second channel; the first channel is provided with a first bandpass filter, and the second channel is provided with a second bandpass filter. pass filter or cutoff filter. In this way, the two-color AR diffraction waveguide according to the embodiment of the present application and the AR glasses including the two-color AR diffraction waveguide are configured on the first channel composed of the entrance pupil area, the first pupil expansion area and the first exit pupil area. A bandpass filter, and a second bandpass filter or cutoff filter is provided on the second channel composed of the entrance pupil area, the second pupil expansion area and the second exit pupil area, so that the first channel and the second exit pupil area The channels conduct light of different colors respectively, so that the left and right sides of the waveguide can display different color images, achieving the effect of a single light source directly presenting a 3D stereoscopic image on AR glasses.

In addition, some embodiments of the present application also provide a single-projector 3D imaging AR glasses, aiming to solve the technical problems of the existing AR glasses using two projectors for imaging, troublesome installation and calibration, and high cost.

The single-projector 3D imaging AR glasses according to the embodiment of the present application may include: a projector, a waveguide lens, a coupling grating, a first light path turning grating, a first coupling out grating, a second light path turning grating, and a second coupling out. grating, first liquid crystal light switch, second liquid crystal light switch and controller. The waveguide lens may include a left eye area, a right eye area and a nose top area connecting the left eye area and the right eye area, the coupling grating is disposed in the nose top area, and the first optical path The turning grating and the first coupling grating are arranged in the left eye area, the second light path turning grating and the second coupling grating are arranged in the right eye area, the coupling grating, the A first image optical path is formed between the first optical path turning grating and the first coupling-out grating, and a second image optical path is formed between the coupling-in grating, the second optical path turning grating and the second coupling-out grating. , the projector is arranged toward the coupling grating. The first liquid crystal light switch is disposed on the first image light path between the coupling grating and the first light path turning grating, and the second liquid crystal light switch is disposed on the coupling grating and the first light path turning grating. The second optical path is diverted between the gratings and the second diagram on the image optical path; or the first liquid crystal optical switch is arranged on the side of the first coupling grating facing the human eye, and the second liquid crystal optical switch is arranged on the side of the second coupling grating facing the human eye. . The controller is connected to the projector, the first liquid crystal light switch and the second liquid crystal light switch. The controller is used to control the first liquid crystal light when the projector outputs an odd frame image. The switch is turned on and the second liquid crystal light switch is turned off, and when the projector outputs an even-numbered frame image, the first liquid crystal light switch is controlled to be turned off and the second liquid crystal light switch is turned on.

In some optional implementations according to the present application, the AR glasses may further include a vision correction system, where the vision correction system includes a first wedge-shaped lens group and a second wedge-shaped lens group.

In some optional embodiments according to the present application, the first wedge-shaped lens group may include a left outer wedge-shaped lens away from the human eye and a left inner wedge-shaped lens close to the human eye, and the left outer wedge-shaped lens and the left inner wedge-shaped lens are close to the human eye. The left inner wedge lens covers the exit pupil area located on the left side of the entrance pupil area, and the optical waveguide is included between the left outer wedge lens and the left inner wedge lens. The projection centers of the outer wedge-shaped lens and the left inner wedge-shaped lens on the optical waveguide sheet coincide with each other; the second wedge-shaped lens group includes a right outer wedge-shaped lens away from the human eye and a right inner wedge-shaped lens close to the human eye, The right outer wedge-shaped lens and the right inner wedge-shaped lens cover the exit pupil area located on the right side of the entrance pupil area, and the right outer wedge-shaped lens and the right inner wedge-shaped lens include all In the optical waveguide sheet, the projection centers of the right outer wedge-shaped lens and the right inner wedge-shaped lens on the optical waveguide sheet coincide with each other.

In some optional implementations according to the present application, the left inner wedge lens and the right inner wedge lens can correct the vertical outgoing beam of the bidirectional waveguide model into a deflected beam, so that the image The sources overlap at the target position to form an object image, and the left outer wedge-shaped lens and the right outer wedge-shaped lens compensate for the light deflection produced by the external light passing through the left inner wedge-shaped lens and the right inner wedge-shaped lens. ; The left outer wedge-shaped lens, the left inner wedge-shaped lens, the right outer wedge-shaped lens, and the right inner wedge-shaped lens all include a far corner end and a near corner end, where the thickness of the far corner end of the wedge lens Greater than the proximal end of the wedge-shaped lens; the distal end of the left outer wedge-shaped lens and the distal end of the right outer wedge-shaped lens are close to the entrance pupil area; the distal end of the left inner wedge-shaped lens and the distal end of the right outer wedge-shaped lens are close to the entrance pupil area; The far end of the right inner wedge lens is away from the entrance pupil area; in the first wedge lens group, the far end of the left outer wedge lens is opposite to the near end of the left inner wedge lens. , the near corner end of the left outer wedge-shaped lens is opposite to the far corner end of the left inner wedge-shaped lens; in the second wedge-shaped lens group, the far corner end of the right outer wedge-shaped lens is opposite to the right corner end of the right outer wedge-shaped lens. The proximal end of the side inner wedge-shaped lens is in an opposite position, and the proximal end of the right outer wedge-shaped lens is in an opposite position to the distal end of the right inner wedge-shaped lens.

In some optional implementations according to the present application, the left inner wedge lens and the right inner wedge lens correct the vertical outgoing beam of the bidirectional waveguide model into a deflected beam, so that the image source Coinciding at the target position to form an object image may include: calculating the deflection angle of the left inner wedge-shaped lens and the right inner wedge-shaped lens on the outgoing light beam according to the human eye pupil distance and arc length formula; according to the deflection Angle to obtain the wedge angle of the left outer wedge-shaped lens, the left inner wedge-shaped lens, the right outer wedge-shaped lens, and the right inner wedge-shaped lens, the formula is:

Among them, α is the deflection angle, θ is the wedge angle, n1 is the refractive index of the wedge lens material, and n2 is the refractive index of the medium where the wedge lens is located.

In some optional implementations according to the present application, when the first liquid crystal optical switch is disposed between the coupling grating and the first optical path switch When on the first image optical path between gratings, a first polarizer is pasted on the surface of the first liquid crystal light switch facing the coupling grating;

When the second liquid crystal light switch is disposed on the second image light path between the coupling grating and the second light path turning grating, the second liquid crystal light switch faces the surface of the coupling grating. A second polarizer is pasted.

In some optional implementations according to the present application, a first optical switch for accommodating the first liquid crystal light switch may be provided on the waveguide lens between the coupling grating and the first optical path turning grating. The first liquid crystal light switch is detachably arranged in the first trench, and the waveguide lens between the coupling grating and the second light path turning grating is provided with a hole for accommodating the A second groove for a second liquid crystal light switch, the second liquid crystal light switch is disposed in the second groove.

In some optional implementations according to the present application, the AR glasses may further include a support frame for fixing the first liquid crystal light switch and the second liquid crystal light switch.

In some optional implementations according to the present application, when the first liquid crystal light switch is disposed on the side of the first coupling grating facing the human eye, the first liquid crystal light switch faces the first A third polarizer is pasted on the surface of the coupling grating;

When the second liquid crystal light switch is disposed on the side of the second coupling grating facing the human eye, a fourth polarizer is pasted on the surface of the second liquid crystal light switch facing the second coupling grating.

In some optional implementations according to the present application, the coupling grating, the first light path turning grating, the first coupling grating, the second light path turning grating and the second coupling grating They can all be surface relief gratings or volume holographic gratings.

In some optional implementations according to the present application, the edge of the waveguide lens may be coated with a light-shielding layer.

The beneficial effects are: this application provides a single-projector 3D imaging AR glasses, including: a projector, a waveguide lens, a coupling grating, a first light path turning grating, a first coupling grating, a second light path turning grating, and a third light path turning grating. Two outcoupling gratings, a first liquid crystal light switch, a second liquid crystal light switch and a controller; the first liquid crystal light switch is arranged between the coupling grating and the first light path turning grating, and the second liquid crystal light switch is arranged between the coupling grating and the first light path turning grating. The second light path turns between the gratings; or the first liquid crystal light switch is arranged on the side of the first coupling grating facing the human eye, and the second liquid crystal light switch is arranged on the side of the second coupling grating facing the human eye; the controller and The projector, the first liquid crystal light switch and the second liquid crystal light switch are connected. The AR glasses of this application only need to use a single projector and two liquid crystal light switches to achieve 3D effect imaging in the human eye, which reduces the difficulty of installation and calibration and saves costs.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, which are of great significance to this field. Ordinary technicians can also obtain other drawings based on these drawings without exerting creative work.

Figure 1 is a first structural schematic diagram of a two-color AR diffraction waveguide provided by an embodiment of the present application;

Figure 2 is a second structural schematic diagram of a two-color AR diffraction waveguide provided by an embodiment of the present application;

Figure 3 is a schematic diagram of the first structure of a two-color AR diffraction waveguide provided by an embodiment of the present application from another angle;

Figure 4 is a schematic diagram of the second structure of a two-color AR diffraction waveguide provided by an embodiment of the present application from another angle;

Figure 5 is a schematic diagram of the optical path transmission of the first structure of a two-color AR diffraction waveguide provided by the embodiment of the present application;

Figure 6 is a schematic diagram of the optical path transmission of the second structure of a two-color AR diffraction waveguide provided by the embodiment of the present application;

Figure 7 is a schematic structural diagram of an embodiment of the waveguide plate assembly of the present application;

Figure 8 is a schematic diagram of the optical path of the left waveguide plate in the waveguide plate assembly shown in Figure 7;

Figure 9 is a diagram showing changes in the optical path of the input light from the outside of the waveguide assembly shown in Figure 7;

Figure 10 is a diagram showing changes in the optical path of the input light from the inside of the waveguide assembly shown in Figure 7;

Figure 11 is a schematic structural diagram of another embodiment of the waveguide plate assembly of the present application;

Figure 12 is a perspective view of a single projector 3D imaging AR glasses top view according to the embodiment of the present application;

Figure 13 is a perspective view of the AR glasses of Figure 1 from a front view;

Figure 14 is a schematic diagram of the connection structure of a first liquid crystal optical switch and a second liquid crystal optical switch provided in an embodiment of the present application;

Figure 15 is a perspective view of another single-projector 3D imaging AR glasses top view provided by the embodiment of the present application;

Figure 16 is a perspective view of the AR glasses of Figure 4 from a front view;

Figure 17 is a schematic diagram of the optical path of the AR glasses in Figure 4;

Figure 18 is a schematic structural diagram of a binocular AR eyepiece vision correction system provided by an embodiment of the present application;

Figure 19 is another structural schematic diagram of the binocular AR eyepiece vision correction system provided by the embodiment of the present application; and

Figure 20 is another structural schematic diagram of the binocular AR eyepiece visual correction system provided by the embodiment of the present application;.

The reference numbers are as follows:

1-Dual-color AR diffraction waveguide; 11-entrance pupil area; 21-first pupil expansion area; 22-second pupil expansion area; 31-first exit pupil area; 32-second exit pupil area; 41-first zone Pass filter; 42-second bandpass filter or cut-off filter; 10-projector; 20-waveguide lens; 30-coupling grating; 40-first light path turning grating; 50-first coupling grating; 60 - The second light path steering grating; 70 - the second coupling grating; 80 - the first liquid crystal light switch; 90 - the second liquid crystal light switch; 100 - left eye area; 110 - right eye area; 120 - top of nose area; 130 -The first polarizer; 140-the second polarizer; 150-the first groove; 160-the second groove; 170-support frame; 180-the third polarizer; 190-the fourth polarizer; 200-waveguide plate Components; 211-left waveguide plate; 212-right waveguide plate; 213-rotating shaft; 1a-left entrance pupil grating unit, 2a-left pupil expansion grating unit 2a; 3a-left exit pupil grating unit; 1b-right entrance pupil grating unit 1b; 2b-right pupil expansion grating unit; 3b-right exit pupil grating unit; 301-first wedge-shaped lens group; 302-second wedge-shaped lens group; 3011-left outer wedge-shaped lens; 3012-left inner wedge-shaped lens; 2000-bidirectional waveguide model; 2001-entrance pupil area; 2021-left pupil expansion area; 2022-right pupil expansion area; 2031-left exit pupil area; 2032-right exit pupil area; 3021- Right outer wedge-shaped lens; 3022-right inner wedge-shaped lens; 30111-far end of left outer wedge-shaped lens; 30112-near end of left outer wedge-shaped lens; 30122-near end of left inner wedge-shaped lens; 30121- The far end of the left inner wedge-shaped lens; 30211 - the far end of the right outer wedge-shaped lens; 30222 - the near end of the right inner wedge-shaped lens; 30212 - the near end of the right outer wedge-shaped lens; 30221 - the right inner wedge The far end of the lens.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, 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.

It should be understood that, when used in this specification and the appended claims, the terms "comprises" and "comprises" indicate the presence of described features, integers, steps, operations, elements and/or components but do not exclude the presence of one or Various other features, integers, steps, operations, elements, components and/or or the existence or addition to a collection thereof.

It should also be understood that the terminology used in the specification of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this specification and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms unless the context clearly dictates otherwise.

It will be further understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items. .

Please refer to Figure 1 and Figure 2 below. The embodiment of the present application provides a two-color AR diffraction waveguide. The two-color AR diffraction waveguide may include: an entrance pupil area 11 located in the center of the waveguide, symmetrically distributed on both sides of the entrance pupil area 11 The first pupil expansion area 21 and the second pupil expansion area 22, the first exit pupil area 31 disposed below the first pupil expansion area 21, and the second exit pupil disposed below the second pupil expansion area 22 Area 32.

In the illustrated embodiment, the entrance pupil area 11, the first pupil expansion area 21 and the first exit pupil area 31 form a first channel, and the entrance pupil area 11, the second pupil expansion area 22 and the second exit pupil area 22 form a first channel. The pupil area 32 forms a second channel; a first bandpass filter 41 is provided on the first channel, and a second bandpass filter or cutoff filter 42 is provided on the second channel.

In an embodiment according to the present application, the two-color AR diffractive waveguide may include an entrance pupil area 11, a pupil expansion area, and an exit pupil area. The pupil expansion area specifically includes a first pupil expansion area 21 and a second pupil expansion area 22. The pupil area specifically includes a first exit pupil area 31 and a second exit pupil area 32, wherein the entrance pupil area 11, the first pupil expansion area 21, and the first exit pupil area 31 form a first channel on the waveguide, and the The entrance pupil area 11, the second pupil expansion area 22, and the second exit pupil area 32 form a second channel on the waveguide. At the same time, a first bandpass filter 41 and a second bandpass filter or cut-off filter 42 are respectively provided on the first channel and the second channel, so that the first channel can only conduct the first bandpass filter 41 The second channel can only transmit the colored light transmitted through the second band-pass filter or the cut-off filter 42 .

According to the embodiment of the present application, the first bandpass filter 41 is provided on the first channel composed of the entrance pupil area 11, the first pupil expansion area 21 and the first exit pupil area 31, and on the first channel composed of the entrance pupil area 11, A second bandpass filter or cutoff filter 42 is provided on the second channel composed of the second pupil expansion area 22 and the second exit pupil area 32, so that the first channel and the second channel transmit light of different colors respectively, thereby achieving The left and right sides of the waveguide display different color images, achieving the effect of a single light source directly presenting a 3D stereoscopic image on AR glasses.

It can be understood that in order to allow the first channel and the second channel to transmit light of different colors, the bandpass filter in the embodiment of the present application can also be replaced with a cut-off filter. In this way, it is also possible to cut off part of the color light and pass it through. Partial color light effect.

In some embodiments according to the present application, the first bandpass filter 41 may be disposed in the waveguide between the entrance pupil area 11 and the first pupil expansion area 21 , and the second bandpass filter or The cutoff filter 42 may be disposed in the waveguide between the entrance pupil area 11 and the second pupil expansion area 22 .

In some embodiments according to the present application, the first bandpass filter 41 may be disposed in the waveguide between the entrance pupil area 11 and the first pupil expansion area 21 , and the second bandpass filter or The cutoff filter 42 may be disposed on the waveguide surface between the entrance pupil area 11 and the second pupil expansion area 22 .

In some embodiments according to the present application, with reference to FIG. 1 , the first bandpass filter 41 may be disposed between the entrance pupil area 11 and the first pupil expansion area 21 , and the second bandpass filter 41 may be disposed between the entrance pupil area 11 and the first pupil expansion area 21 . Or the cutoff filter 42 can be disposed between the entrance pupil area 11 and the second pupil expansion area 22, so that the light entering the waveguide from the entrance pupil area 11 can only conduct light of different colors in the first channel and the second channel respectively. Light.

In some optional implementations according to the present application, with reference to FIG. 3 , the first bandpass filter 41 is 2 to 4 mm away from the left edge of the entrance pupil area 11 , and the second bandpass filter or The cutoff filter 42 is 2 to 4 mm away from the right edge of the entrance pupil area 11 .

In some embodiments according to the present application, with reference to FIG. 2 , the first bandpass filter 41 may be placed in the waveguide between the first pupil expansion area 21 and the first exit pupil area 31 , so The second bandpass filter or cutoff filter 42 may be disposed in the waveguide between the second pupil expansion area 22 and the second exit pupil area 32 .

In some embodiments according to the present application, the first bandpass filter 41 may be placed in the waveguide between the first pupil expansion area 21 and the first exit pupil area 31 , and the second bandpass filter 41 may be placed in the waveguide between the first pupil expansion area 21 and the first exit pupil area 31 . A pass filter or cutoff filter 42 may be disposed on the waveguide surface between the second pupil expansion area 22 and the second exit pupil area 32 .

In an embodiment according to the present application, the first bandpass filter 41 may be disposed between the first pupil expansion area 21 and the first exit pupil area 31 , and the second bandpass filter or cutoff filter The sheet 42 may be disposed between the second pupil expansion area 22 and the second exit pupil area 32, so that the light beams expanded by the first pupil expansion area 21 and the second pupil expansion area 22 can only be directed toward the corresponding The first exit pupil area 31 and the second exit pupil area 32 conduct the colored light respectively passed by the first bandpass filter 41 and the second bandpass filter or cutoff filter 42 .

In some optional embodiments according to the present application, with reference to FIG. 4 , the first bandpass filter 41 is 1 to 2 mm away from the lowermost edge of the first pupil expansion area 21 , and the second bandpass filter is Or the cutoff filter 42 is 1 to 2 mm away from the lowermost edge of the second pupil expansion area 22 .

In some embodiments according to the present application, the first bandpass filter 41 may be a red bandpass filter, so that the first channel conducts red light;

The second bandpass filter 42 may be a blue bandpass filter or the cutoff filter 42 may be a red cutoff filter, so that the second channel transmits blue light or blue-green light.

In the embodiment according to the present application, a red band-pass filter is used as the first band-pass filter 41 , and a blue band-pass filter or a red cut-off filter is used as the second band-pass filter or By cutting off the filter 42, the first channel can only transmit red light, and the second channel can only transmit blue light or blue-green light. In other embodiments, the first bandpass filter 41 may also be a blue bandpass filter, and the second bandpass filter or cutoff filter 42 may be a red bandpass filter or a blue cutoff filter. . Of course, in order to make the first channel transmit red light and the second channel transmit blue light, the red bandpass filter can also be replaced with a blue cutoff filter.

In some specific embodiments according to the present application, as shown in FIG. 5 , the entrance pupil area 11 is used as a boundary on the waveguide, and the waveguide between the left side of the entrance pupil area 11 and the right side of the first pupil expansion area 21 A red bandpass filter is provided in the waveguide with a bandwidth of 590-640nm, and a blue bandpass filter is provided in the waveguide between the right side of the entrance pupil area 11 and the left side of the second pupil expansion area 22 with a bandwidth of 590-640nm. 420~480nm (or red cutoff filter, the cutoff band is 590-640nm). A color 3D image light source is set up in the entrance pupil area 11. The light source enters the two-color AR diffraction waveguide. The RGB three-color light enters the waveguide from the entrance pupil area 11. The light after passing through the red bandpass filter passes through the left waveguide (i.e., the The first channel) only passes red light into the first pupil expansion area 21. The grating on the first pupil expansion area 21 diffracts the red light into the first exit pupil area 31. From the first exit pupil area 31 The red light diffracted by the grating on 31 finally enters the human eye; similarly, the RGB three-color light enters the waveguide from the entrance pupil area 11, and the light that passes through the blue bandpass filter or the red cutoff filter passes through the right waveguide (that is, the second channel) only enters the second pupil expansion area 22 through blue light (or blue-green light), and the grating on the second pupil expansion area 22 diffracts blue light (or blue-green light) into the second exit pupil area 32, The blue light (or blue-green light) diffracted from the grating on the second exit pupil area 32 finally enters the human eye, and the red and blue images of the left and right eyes seen by the human eye are combined into body image.

In other specific embodiments according to the present application, as shown in Figure 6, the left eye waveguide pupil expansion area (ie, the first pupil expansion area 21) and the exit pupil area (ie, the first pupil expansion area) on the waveguide are A red bandpass filter is installed in the waveguide between the pupil area 21) with a bandwidth of 590~640nm; in the right eye waveguide pupil expansion area (i.e. the second pupil expansion area 22) and the exit pupil area (i.e. the second pupil area 22) A blue bandpass filter with a bandwidth of 420-480nm (or a red cutoff filter with a cutoff band of 590-640nm) is installed in the waveguide between the pupil expansion areas 22). RGB trichromatic light enters the waveguide from the entrance pupil area 11, and enters the first exit pupil area 31 by diffracting the grating on the first pupil area 21. The light after passing through the red bandpass filter passes through the waveguide. Only red light enters the first exit pupil area 31, and the red light diffracted from the grating on the first exit pupil area 31 finally enters the human eye; RGB tricolor light enters the waveguide from the entrance pupil area 11, and enters the The grating on the second pupil expansion area 22 diffracts three-color light into the second exit pupil area 32. The light that passes through the blue bandpass filter (or red cutoff filter) only enters through the blue light (or blue-green light) in the waveguide. In the second exit pupil area 32, the blue light (or blue-green light) diffracted from the grating on the second exit pupil area 32 finally enters the human eye, and the red and blue images of the left and right eyes seen by the human eye are synthesized into a stereoscopic image.

In some embodiments according to the present application, the length of the waveguide in the y-axis direction may be 100-120 mm, the width in the x-axis direction may be 35-50 mm, and the thickness may be 0.5-1 mm;

The diameter of the entrance pupil area 11 may be 4-6 mm; the length of the first exit pupil area 31 and the second exit pupil area 32 are both 30-40 mm, and the width is 20-30 mm; the first pupil expansion The width of the area 21 and the second pupil expansion area 22 is 2 to 5 times the diameter of the entrance pupil area 11 , and the width of the side close to the entrance pupil area 11 is 2 times the diameter of the entrance pupil area 11 ~3 times, the width of the side away from the entrance pupil area 11 is 3~5 times the diameter of the entrance pupil area 11, and the length is 1.5~2 times the length of the first exit pupil area 31 or the second exit pupil area 32 times;

The length of the first bandpass filter 41 and the second bandpass filter or cutoff filter 42 can be less than 0.5mm, the width is 6-10mm and greater than the diameter of the entrance pupil area 11, and the thickness is the same as that of the waveguide. Same thickness.

In an embodiment according to the present application, with reference to Figures 3 and 4, the length L of the waveguide in the y direction ranges from 100 to 120mm, the width W in the x direction ranges from 35 to 50mm, and the thickness H ranges from 0.5 to 1mm; The diameter of the entrance pupil area 11 is D1, which ranges from 4 to 6 mm; the length L3 of the first exit pupil area 31 (or the second exit pupil area 32) ranges from 30 to 40 mm, and the width W3 ranges from 20 to 30 mm; so The width W1 of the first pupil expansion area 21 (or the second pupil expansion area 22) is 2 to 5 times that of D1, and the side width w2 close to the entrance pupil area 11 is 2 to 3 times that of D1. , the width w3 of the side away from the entrance pupil area 11 is 3 to 5 times of D1, and the length L2 is 1.5 to 2 times of L3. The width of the first bandpass filter 41 (or the second bandpass filter or cutoff filter 42) is greater than the diameter D1 of the entrance pupil area 11, ranging from 6 to 10 mm, and the thickness h1 is equal to the thickness of the waveguide. H is the same, with a value of 0.5~1mm, and the length l1<0.5mm.

In some embodiments according to the present application, the waveguide may be an integrated butterfly waveguide for left and right eyes;

The entrance pupil area 11, the first pupil expansion area 21, the second pupil expansion area 22, the first exit pupil area 31 and the second exit pupil area 32 can all adopt diffraction gratings, and the diffraction gratings are surface relief gratings or volumetric gratings. Holographic grating.

In some embodiments according to the present application, the diffraction grating may correspond to an entrance pupil grating unit, a pupil expansion grating unit and an exit pupil grating unit.

In summary, in the embodiment of the present application, an integrated butterfly waveguide structure is used for the left and right eyes, and red and blue bandpass filters (or red cutoff filters) are respectively provided on the left and right sides of the waveguide, so that the left eye waveguide only displays The red part, the right eye waveguide only displays the blue part, thus realizing the left and right eye Seeing different color images produces a 3D red and blue effect. The left and right eye integrated butterfly waveguide structure includes an entrance pupil area 11, and two pupil expansion areas (i.e., the first pupil expansion area 21 and the second pupil expansion area) distributed left and right with the entrance pupil area 11 as the axis of symmetry. The pupil area 22) is distributed in the two exit pupil areas below the pupil expansion area (ie, the first exit pupil area 31 and the second exit pupil area 32). Diffraction gratings are provided in the five areas, and the diffraction gratings can be surface relief gratings or volume holographic gratings.

In some embodiments according to the present application, the waveguide may further include a waveguide plate assembly 200 .

Refer to Figures 7 and 11, which are respectively schematic structural diagrams of two embodiments of the waveguide plate assembly of the present application. According to the illustrated exemplary embodiment, the waveguide plate assembly 200 of this embodiment includes a left waveguide plate 211 and a right waveguide plate 212, corresponding to the left eye and the right eye respectively. Therefore, the two waveguide plates are centered on the connection, and the structure is mirror symmetrical. In order to ensure the uniformity of light irradiation, the left and right waveguide plates are also made of the same material.

Both waveguides can include an entrance pupil grating unit, a pupil expansion grating unit and an exit pupil grating unit. The input light enters the entrance pupil grating unit in a transmission manner. The light passes through the pupil expansion grating unit to achieve lateral pupil expansion, and then passes through the exit pupil grating unit. The pupil grating unit realizes longitudinal pupil expansion and exports it to the human eye. Specifically, the entrance pupil grating unit is disposed close to the connection, the pupil expansion grating unit is disposed on a side of the entrance pupil grating unit away from the connection in the horizontal direction, and the exit pupil grating unit is disposed below the pupil expansion grating unit.

In the illustrated exemplary embodiment, the left waveguide plate 211 may include a left entrance pupil grating unit 1a, a left pupil expansion grating unit 2a and a left exit pupil grating unit 3a; the right waveguide plate 212 may include a right entrance pupil grating unit 1b, a right The pupil expansion grating unit 2b and the right exit pupil grating unit 3b.

The two waveguide plates can form an obtuse angle at the connection, so that when the waveguide plate assembly 200 is used in glasses, it can fit the human face more closely and improve wearing comfort; the obtuse angle in the illustrated exemplary embodiment is greater than or equal to 120 degrees. More suitable for human faces. Moreover, there is an angle between the left and right waveguide plates, and the entrance pupil area is divided into separate left and right entrance pupil grating units, so the crosstalk of light waves on the left and right sides will be greatly reduced.

If the inside of the obtuse angle is taken as the inside of the waveguide plate assembly 200 and the outside of the obtuse angle is taken as the outside of the waveguide plate assembly 200, in the illustrated exemplary embodiment, the input light is input from the outside of the waveguide plate assembly 200 and enters the waveguide plate assembly 200 in a transmission manner. , which can ensure that the direction of the light emitted from the exit pupil grating unit is consistent with the direction of the incident light from the entrance pupil grating unit. In this embodiment, the entrance pupil grating unit, the pupil expansion grating unit and the exit pupil grating unit are all surface relief gratings or volume holographic gratings.

In order to realize the folding connection of the left and right waveguide plates, the two waveguide plates can be formed into an integrated structure, and the integrated structure is bent to form the waveguide plate assembly 200 of the illustrated exemplary embodiment, as shown in FIG. 7 . Specifically, a butterfly-shaped waveguide plate can be used for processing and bending. At this time, the angles of the left and right waveguide plates are fixed, which can ensure the stability of wearing.

The left and right waveguide plates can also be two independent pieces, and can be fixedly connected, for example, through fixing glue, and the angles of the two waveguide plates are fixed. It can also be connected through the rotating shaft 213, as shown in Figure 11. When connected by the rotating shaft 213, the angle of the two waveguide plates is adjustable to facilitate customization of the wearer's face shape. In order to make it easier to use, the rotating shaft 213 can be set so that the left and right waveguide plates can only be folded on the inside of the waveguide plate assembly. Furthermore, it can also be set to limit the folding degree of the left and right waveguide plates to only achieve an obtuse angle between 120 degrees and 180 degrees. between.

The reason why the folded waveguide assembly 200 of the present application can achieve normal display is because the input light is incident from the outside of the waveguide assembly 200, and the waveguide assembly of the present application can ensure the consistency of the light path direction. For details, please refer to Figure 8 to Figure 10.

The function of the waveguide plate is to translate the light beam and transfer the light beam from the entrance pupil position to the exit pupil position. The waveguide plate follows the principles of light reflection and transmission. As shown in Figures 8 to 9, the input light enters the waveguide plate through transmission coupling, the output light is in the same direction as the input light, and the optical path direction is not affected by the folding angle of the waveguide plate. Corresponding to the application of AR glasses, as long as the input light transmitted into the waveguide is perpendicular to the human eye, no matter what shape the waveguide is in Angle, the light output to the human eye can enter the human eye vertically.

Correspondingly, in Figure 10, the input light is coupled into the waveguide plate by reflection, and the direction of the optical path is affected by the folding angle of the waveguide plate. If the input light is perpendicular to the human eye, the waveguide must be parallel to ensure that the output light enters the human eye perpendicularly.

To sum up, in this application, for the folded-shaped waveguide component, the input light transmission coupling method is used to achieve normal display.

The left waveguide plate and the right waveguide plate of the waveguide plate assembly of the present application are spliced at a certain angle, which can better fit the human face when used in AR glasses. Moreover, the light incident from the outside of the waveguide assembly can be emitted in the same direction after passing through the entrance pupil grating unit, pupil expansion grating unit and exit pupil grating unit, ensuring that the light can directly enter the human eye without being pinched due to the folding of the waveguide. horn. Guaranteed the effectiveness of AR glasses.

Embodiments of the present application also provide AR glasses, in which the two-color AR diffraction waveguide as described above can be used.

As far as AR glasses are concerned, in the current technical solutions of domestic AR glasses, the mainstream method to produce 3D effects on images is to use a double-sided projector system. The two projectors control the images on the left and right sides respectively. Specifically: use a computer to create After 3D objects are collected, rotate the object to the right by a certain angle along the central axis when collecting images, so that it can adapt to the image seen by the left eye, thereby introducing parallax to the left eye. Similarly, to introduce parallax to the right eye, the object needs to be centered. The image is collected after the axis is rotated to the left by a certain angle. At this point, two images with left and right parallax are obtained, and then two projectors are used to project the left and right parallax images to the left and right eyes respectively. After the retina acquires the image, it is processed by the brain to finally produce a 3D effect. The advantage of using two projectors is that they can control two images separately, which provides prerequisites for three-dimensional display. However, two projectors have to consider image synthesis, installation and calibration are very troublesome, which is not conducive to commercialization.

In order to solve the above technical problems, this application also provides a single projector 3D imaging AR glasses.

Referring to Figures 12 and 13 or referring to Figures 15 and 16, single-projector 3D imaging AR glasses according to an exemplary embodiment of the present application may include: a projector 10, a waveguide lens 20, a coupling grating 30, a first optical path The steering grating 40, the first coupling grating 50, the second light path steering grating 60, the second coupling grating 70, the first liquid crystal light switch 80, the second liquid crystal light switch 90 and the controller; wherein, the projector 10 is used according to A certain refresh rate alternately provides the parallax images required for 3D imaging for the left and right eyes. The coupling grating 30 is used to deflect the light of the parallax image output by the projector 10 at a certain angle so that the light of the parallax image can be fully reflected in the waveguide lens 20 Propagates to the first light path turning grating 40 and the second light path turning grating 60. The first light path turning grating 40 is used to amplify the parallax image and deflect the light of the parallax image to the first coupling grating 50. The second light path turning grating 60 is used for The parallax image is amplified and the light of the parallax image is deflected to the second decoupling grating 70 .

Referring to Fig. 13 or Fig. 16, in an optional embodiment of the present application, the waveguide lens 20 may include a left eye area 100, a right eye area 110 and a link connecting the left eye area 100 and the right eye area 110. Nose top area 120, the coupling grating 30 is disposed in the nose top area 120, the first light path turning grating 40 and the first coupling grating 50 are disposed in the left eye area 100, the The second light path turning grating 60 and the second coupling grating 70 are disposed in the right eye area 110. Referring to Figure 17, the coupling grating 30, the first light path turning grating 40 and the first coupling grating A first image light path is formed between the outgoing gratings 50 , a second image light path is formed between the coupling grating 30 , the second light path turning grating 60 and the second coupling out grating 70 , and the projector 10 faces toward The coupling grating 30 is configured;

Referring to FIG. 12 , the first liquid crystal optical switch 80 may be disposed on the first image optical path between the coupling grating 30 and the first optical path turning grating 40 , and the second liquid crystal optical switch 90 may be Disposed on the second image optical path between the coupling grating 30 and the second optical path turning grating 60;

Or referring to Figures 15 and 17, the first liquid crystal light switch 80 can be disposed on the side of the first coupling grating 50 facing the human eye, so The second liquid crystal optical switch 90 is disposed on the side of the second coupling grating 70 facing the human eye;

The controller may be connected to the projector 10, the first liquid crystal light switch 80 and the second liquid crystal light switch 90. The controller is used to control all the odd frame images when the projector 10 outputs them. The first liquid crystal light switch 80 is turned on, and the second liquid crystal light switch 90 is turned off. When the projector 10 outputs an even-numbered frame image, the first liquid crystal light switch 80 is controlled to be turned off, and the second liquid crystal light switch 90 is turned off. Optical switch 90 is turned on.

Most of the existing AR glasses use two projectors to achieve three-dimensional display. However, dual projectors are difficult to install and difficult to produce. This application uses a single projector to realize three-dimensional display. During installation, it only needs to be aligned with the position of the middle coupling grating 30. The installation difficulty is low and it is easy to produce. In this application, AR glasses are preferably realized by embedding the first liquid crystal light switch 80 (liquid crystal light valve) and the second liquid crystal light switch 90 in the waveguide lenses 20 on both sides of the coupling grating 30 (grating coupler). The embedded Compared with the external liquid crystal light switch in which the first coupling grating 50 is provided on the left eye and the second coupling grating 70 is provided on the right eye, the liquid crystal light switch is installed on both sides of the coupling grating 30 and does not It will increase the thickness of the glasses, so AR glasses can be made more compact. In addition, due to the selectivity of liquid crystal to polarized light, non-polarized light will inevitably lose half of its brightness when passing through the liquid crystal light switch. Blocking it from the waveguide lenses 20 on both sides of the coupling grating 30 will only attenuate the brightness of the projected image, and will not It will affect natural light, so it will not affect the observation of the external environment.

The AR glasses of this application use time-division multiplexing technology to continuously and alternately refresh two images containing different parallax information at a high refresh rate to achieve the three-dimensional display effect of a single projector. Preferably, a projector with a refresh rate of 120Hz is used. The odd-numbered frames import the image containing the left-eye parallax, the even-numbered frames import the image containing the right-eye parallax, and the two images are refreshed alternately. The voltage values of the two liquid crystal light switches are controlled through a controller connected to the projector. When refreshing an odd-numbered frame, the circuit of the first liquid crystal light switch is turned on, and the arrangement direction of the liquid crystal molecules is changed by applying a voltage, so that the light beam passes through the first liquid crystal light switch. At the same time, the circuit of the second liquid crystal light switch is turned off, blocking the right side. The light beam enables the left eye to obtain the image, but the right eye cannot obtain the image; when the even-numbered frame is refreshed, the second liquid crystal light switch circuit is turned on, and the arrangement direction of the liquid crystal molecules is changed by applying voltage, so that the light beam passes through the second liquid crystal light switch, and at the same time Disconnect the circuit of the first liquid crystal light switch and block the left light beam so that the right eye can obtain the image but the left eye cannot obtain the image. Finally, the left and right images appear alternately, and because the refresh rate is greater than 24Hz, reaching 120Hz, it can project two stable images with left and right eye parallax, which will be synthesized by the brain to produce a three-dimensional effect.

Referring to Figures 12 and 14, in an optional embodiment of the present application, when the first liquid crystal light switch 80 is disposed between the coupling grating 30 and the first light path turning grating 40, the first light path turning grating 40 A liquid crystal light switch 80 has a first polarizer 130 pasted on the surface facing the coupling grating 30;

When the second liquid crystal light switch 90 is disposed between the coupling grating 30 and the second light path turning grating 60 , the second liquid crystal light switch 90 is pasted on the surface facing the coupling grating 30 . Two polarizers 140.

Referring to Figure 13, in an optional embodiment of the present application, the waveguide lens 20 between the coupling grating 30 and the first light path turning grating 40 may be provided with a lens for accommodating the first liquid crystal light. The first slot 150 of the switch 80 , the first liquid crystal optical switch 80 is detachably disposed in the first slot 150 , the coupling grating 30 and the second light path turning grating 60 are The waveguide lens 20 may be provided with a second groove 160 for accommodating the second liquid crystal light switch 90 , and the second liquid crystal light switch 90 is disposed in the second groove 160 .

Referring to FIG. 14 , in an optional embodiment of the present application, the AR glasses may further include a support frame 170 for fixing the first liquid crystal light switch 80 and the second liquid crystal light switch 90 . Referring to Figure 15, in an optional embodiment of the present application, when the first liquid crystal optical switch 80 When the first coupling grating 50 is arranged on the side facing the human eye, a third polarizer 180 is pasted on the surface of the first liquid crystal light switch 80 facing the first coupling grating 50;

When the second liquid crystal light switch 90 is disposed on the side of the second coupling grating 70 facing the human eye, a fourth liquid crystal light switch 90 is pasted on the surface facing the second coupling grating 70 . Polarizer 190.

In the illustrated exemplary embodiment, the main principle of the AR glasses of the present application is the combination of time division multiplexing technology and the polarization of light. There is a polarizer in front of the liquid crystal light switch. Since light is polarized, it can be decomposed into s-wave and p-wave, and the two are orthogonal. Based on the light-passing characteristics of liquid crystal, only light waves parallel to its arrangement direction are allowed to pass through, while light waves perpendicular to its arrangement direction will be absorbed. Here, it is assumed that the s wave is parallel to the horizontal line. When no voltage is applied, the liquid crystal molecules are also arranged parallel to the horizontal line. The polarizer blocks the s wave and transmits the p wave. When light passes through the polarizer 5, the s wave is blocked and the p wave passes. At this time, the liquid crystal light switch on the left does not apply voltage and the p wave cannot pass. The liquid crystal light switch on the right applies voltage and the liquid crystal molecules become vertically distributed. The p-wave passes through, resulting in a black screen in the left eye and a picture in the right eye; when voltage is applied to the left LCD screen and the right side is powered off, the light wave on the left passes through and a picture appears, while the light wave on the right is blocked and a black screen appears. The left and right voltages cooperate with the projector's refresh alternating switch to ultimately achieve the situation where the left and right images appear alternately. In this application, a polarizer is affixed to the surface of the first liquid crystal light switch 80 facing the first coupling grating 50 and the surface of the second liquid crystal light switch 90 facing the second coupling grating 70 in order to make the exit pupil beam It becomes linearly polarized light, and then is switched and modulated by the first liquid crystal light switch 80 and the second liquid crystal light switch 90 before being set into the left and right eyes of the person.

In an optional embodiment of the present application, the coupling grating 30 , the first light path turning grating 40 , the first coupling grating 50 , the second light path turning grating 60 and the second coupling out The gratings 70 are all surface relief gratings or volume holographic gratings. In the illustrated exemplary embodiment, each grating in the technical solution of the present application is preferably a surface relief grating or a volume holographic grating, which can greatly reduce the cost of implementing the technical solution and facilitate the popularization of AR glasses.

In some optional embodiments according to the present application, the edge of the waveguide lens 20 is coated with a light-shielding layer. The light-shielding layer can use any black paint in the existing technology, with the purpose of preventing external light from interfering with the parallax image light, so as to improve the final imaging effect.

Referring to FIGS. 18 to 20 , in an optional embodiment of the present application, AR glasses may also include a vision correction system, and the vision correction system includes a first wedge-shaped lens group 301 and a second wedge-shaped lens group 302 .

In some optional implementations according to the present application, as shown in FIGS. 18 to 20 , the first wedge lens group 301 of the vision correction system includes a left outer wedge lens 3011 far away from the human eye and a left outer wedge lens 3011 close to the human eye. The side inner wedge lens 3012, the left outer wedge lens 3011 and the left inner wedge lens 3012 cover the exit pupil area 2031 placed on the left side of the entrance pupil area 2001, and between the left outer wedge lens 3011 and the left inner wedge lens 3012 Including the optical waveguide plate of the two-way waveguide model 2000, the projection centers of the left outer wedge lens 3011 and the left inner wedge lens 3012 on the optical waveguide plate of the two-way waveguide model 2000 coincide. The second wedge lens group 302 of the vision correction system includes a right outer wedge lens 3021 away from the human eye and a right inner wedge lens 3022 close to the human eye. The right outer wedge lens 3021 and the right inner wedge lens 3022 cover and are placed in the The exit pupil area 2032 on the right side of the pupil area 2001, and the optical waveguide plate of the two-way waveguide model 2000 is included between the right outer wedge lens 3021 and the right inner wedge lens 3022, the right outer wedge lens 3021 and the right inner wedge lens 3022 The projection centers of the optical waveguide plates of the bidirectional waveguide model 2000 coincide with each other.

In some optional implementations according to the present application, the optical waveguide sheet of the bidirectional waveguide model 2000 includes an entrance pupil area 2001 placed in the middle, a pupil expansion area 2021 placed on the left side of the entrance pupil area 2001, and a pupil expansion area 2021 placed on the left side of the entrance pupil area 2001. The pupil expansion area 2022 on the right side of 2001, the exit pupil area 2031 adjacent to the pupil expansion area 2021, and the exit pupil area 2032 adjacent to the pupil expansion area 2022. Among them, the image source is input vertically from the entrance pupil area 2001, It exits vertically from the exit pupil area 2031 and the exit pupil area 2032.

In some optional implementations according to the present application, as shown in Figures 18 to 20, the left inner wedge lens 3012 and the right inner wedge lens 3022 are used to correct the vertical outgoing beam of the bidirectional waveguide model to Deflect the light beam so that the image sources coincide at the target position to form an object image. The left outer wedge lens 3011 and the right outer wedge lens 3021 are used to detect external light passing through the left inner wedge lens 3012 and the right inner wedge lens 3022. The resulting light deflection is compensated. The left outer wedge lens 3011, the left inner wedge lens 3012, the right outer wedge lens 3021, and the right inner wedge lens 3022 all include a far corner end and a near corner end, where the thickness of the far corner end of the wedge lens is greater than the near corner of the wedge lens. end; the far corner end 30111 of the left outer wedge-shaped lens 3011 and the far corner end 30211 of the right outer wedge-shaped lens 3021 are close to the entrance pupil area 2001, the far corner end 30121 of the left inner wedge-shaped lens 3012 and the right inner wedge-shaped lens 3022 The far corner end 30221 is far away from the entrance pupil area 2001; in the first wedge-shaped lens group 301, the far corner end 30111 of the left outer wedge-shaped lens 3011 is opposite to the near corner end 30122 of the left inner wedge-shaped lens 3012. The near end 30112 is opposite to the far end 30121 of the left inner wedge lens 3012; in the second wedge lens group 302, the far end 30211 of the right outer wedge lens 3021 is opposite to the near end 30222 of the right inner wedge lens 3022. , the proximal corner end 30212 of the right outer wedge-shaped lens 3021 is opposite to the distal corner end 30221 of the right inner wedge-shaped lens 3022.

In some optional implementations according to the present application, the left inner wedge lens 3012 and the right inner wedge lens 3022 are used to correct the outgoing beam that emerges vertically from the bidirectional waveguide model into a deflected beam so that the image source coincides with the target position. Forming the object image may include: calculating the deflection angle of the left inner wedge-shaped lens and the right inner wedge-shaped lens on the outgoing light beam according to the human eye pupil distance and arc length formula; obtaining the left side according to the deflection angle The wedge angle of the outer wedge-shaped lens, the left inner wedge-shaped lens, the right outer wedge-shaped lens, and the right inner wedge-shaped lens is:

In this way, through this visual correction system, a two-way waveguide model is used, while the light deflection characteristics of the wedge lens are used to change the imaging distance of the image source, and an inverted wedge lens is used to compensate for the impact of the first wedge lens on the external environment. Impact: Based on the characteristics of the wedge-shaped lens, this compensation method will not introduce aberrations and interfere with imaging. At the same time, this compensation method is suitable for binocular imaging and has higher use value for head-mounted AR devices. In summary, when using the visual correction system proposed in the embodiment of this application, it is only necessary to ensure that the image source can enter the waveguide plate vertically, so that the light beam can exit perpendicular to the exit pupil area, so that the images on both sides can be finally synthesized under binoculars Therefore, compared to continuously adjusting the inclination angle of its incident beam and combining other phase difference correction methods, its production steps are simple and the cost is low.

To sum up, this application provides a single-projector 3D imaging AR glasses, including: a projector, a waveguide lens, a coupling grating, a first light path turning grating, a first coupling grating, a second light path turning grating, The second coupling grating, the first liquid crystal light switch and the second liquid crystal light switch; the coupling grating, the first light path turning grating and the first coupling grating form a first image light path, the coupling grating, the second light path turning grating A second image light path is formed between the coupling grating and the second coupling grating; the first liquid crystal optical switch is arranged between the coupling grating and the first optical path turning grating, and the second liquid crystal optical switch is arranged between the coupling grating and the second optical path turning grating. time; or the first liquid crystal optical switch is arranged on the side of the first coupling grating facing the human eye, and the second liquid crystal optical switch is arranged on the side of the second coupling grating facing the human eye. The AR glasses of this application only need to use a single projector and two liquid crystal light switches to achieve 3D effect imaging in the human eye, which reduces the difficulty of installation and calibration and saves costs.

Each embodiment in the specification is described in a progressive manner, and each embodiment focuses on its differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other. As for the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple. For relevant details, please refer to the description in the method section. It should be noted that for those of ordinary skill in the art, several improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

It should also be noted that in this specification, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that these entities or operations There is no such actual relationship or sequence between operations. Furthermore, the terms "comprises," "comprises," or any other variations thereof are intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also those not expressly listed other elements, or elements inherent to the process, method, article or equipment. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of additional identical elements in a process, method, article, or device that includes the stated element.

Industrial applicability

This application discloses a two-color AR diffraction waveguide, single projector 3D imaging AR glasses and AR glasses. The waveguide includes: an entrance pupil area located in the center of the waveguide, a first pupil expansion area symmetrically distributed on both sides of the entrance pupil area and The second pupil expansion area, the first exit pupil area provided below the first pupil expansion area, and the second exit pupil area provided below the second pupil expansion area; the entrance pupil area, the first pupil expansion area and the first exit pupil The area forms the first channel, the entrance pupil area, the second pupil expansion area and the second exit pupil area form the second channel; the first channel is provided with a first bandpass filter, and the second channel is provided with a second bandpass filter. slice or cutoff filter. This application achieves this by arranging a first bandpass filter and a second bandpass filter or a cut-off filter on the first channel and the second channel of the waveguide, so that the first channel and the second channel conduct light of different colors respectively. The left and right sides of the waveguide display different color images, achieving the effect of a single light source presenting a 3D stereoscopic image on AR glasses.

In addition, it can be understood that the two-color AR diffraction waveguide, single projector 3D imaging AR glasses and AR glasses of the present application are reproducible and can be applied in the field of AR display technology.

Claims

A two-color AR diffraction waveguide, characterized in that it includes: an entrance pupil area located in the center of the waveguide, a first pupil expansion area and a second pupil expansion area symmetrically distributed on both sides of the entrance pupil area, and is provided in the first pupil area. a first exit pupil area below the pupil expansion area and a second exit pupil area provided below the second pupil expansion area; wherein the entrance pupil area, the first pupil expansion area and the first exit pupil area form a first channel, the entrance pupil area, the second pupil expansion area and the second exit pupil area form a second channel; the first channel is provided with a first bandpass filter, and the second channel is provided with a second bandpass filter. pass filter or cutoff filter.
The two-color AR diffraction waveguide according to claim 1, wherein the first bandpass filter is disposed in the waveguide between the entrance pupil area and the first pupil expansion area, and the second bandpass filter A sheet or cutoff filter is disposed in the waveguide between the entrance pupil area and the second pupil expansion area.
The two-color AR diffraction waveguide according to claim 1, wherein the first bandpass filter is disposed in the waveguide between the entrance pupil area and the first pupil expansion area, and the second bandpass filter A sheet or cutoff filter is disposed on the waveguide surface between the entrance pupil area and the second pupil expansion area.
The two-color AR diffraction waveguide according to claim 1, wherein the first bandpass filter is disposed in the waveguide between the first pupil expansion area and the first exit pupil area, and the second bandpass filter is disposed in the waveguide between the first pupil expansion area and the first exit pupil area. A pass filter or a cutoff filter is disposed in the waveguide between the second pupil expansion area and the second exit pupil area.
The two-color AR diffraction waveguide according to claim 1, wherein the first bandpass filter is disposed in the waveguide between the first pupil expansion area and the first exit pupil area, and the second bandpass filter is disposed in the waveguide between the first pupil expansion area and the first exit pupil area. A pass filter or a cutoff filter is disposed on the waveguide surface between the second pupil expansion area and the second exit pupil area.
The two-color AR diffraction waveguide according to claim 2 or 3, characterized in that the first bandpass filter is 2 to 4mm away from the left edge of the entrance pupil area, and the second bandpass filter or cutoff The filter is 2 to 4 mm away from the right edge of the entrance pupil area.
The two-color AR diffraction waveguide according to claim 4 or 5, characterized in that the first bandpass filter is 1 to 2mm away from the lowermost edge of the first pupil expansion area, and the second bandpass filter is either The cut-off filter is 1 to 2 mm away from the lowermost edge of the second pupil expansion area.
The two-color AR diffraction waveguide according to claim 1, wherein the first band-pass filter is a red band-pass filter, so that the first channel conducts red light; the second band-pass filter It is a blue bandpass filter or the cutoff filter is a red cutoff filter, so that the second channel transmits blue light or blue-green light.
The two-color AR diffraction waveguide according to claim 8, characterized in that the bandwidth of the red bandpass filter is 590~640nm, the bandwidth of the blue bandpass filter is 420~480nm, and the red cutoff filter The cut-off band of the chip is 590~640nm.
The two-color AR diffraction waveguide according to claim 1, characterized in that the length of the waveguide in the y-axis direction is 100~120mm, the width in the x-axis direction is 35~50mm, and the thickness is 0.5~1mm; The diameter of the pupil area is 4~6mm; the length of the first exit pupil area and the second exit pupil area are both 30~40mm, and the width is 20~30mm; the first pupil expansion area and the second pupil expansion area The width of the entrance pupil area is 2 to 5 times the diameter of the entrance pupil area, and the side width close to the entrance pupil area is 2 to 3 times the diameter of the entrance pupil area, and the side width away from the entrance pupil area is 2 to 3 times the diameter of the entrance pupil area. It is 3 to 5 times the diameter of the entrance pupil area, and the length is 1.5 to 2 times the length of the first exit pupil area or the second exit pupil area. times; the length of the first bandpass filter and the second bandpass filter or cutoff filter is less than 0.5mm, the width is 6~10mm and greater than the diameter of the entrance pupil area, and the thickness is the same as that of the waveguide. Same thickness.
The two-color AR diffraction waveguide according to claim 1, characterized in that the waveguide is an integrated butterfly waveguide for left and right eyes;

The entrance pupil area, the first pupil expansion area, the second pupil expansion area, the first exit pupil area and the second exit pupil area all adopt diffraction gratings, and the diffraction gratings are surface relief gratings or volume holographic gratings.
The two-color AR diffraction waveguide according to claim 11, wherein the diffraction grating corresponds to an entrance pupil grating unit, a pupil expansion grating unit and an exit pupil grating unit.
The two-color AR diffraction waveguide according to claim 11 or 12, further comprising a waveguide plate assembly, the waveguide plate assembly includes a left waveguide plate and a right waveguide plate connected to each other, with the connection as the center, the left waveguide plate assembly is The structure of the waveguide plate and the right waveguide plate are mirror symmetrical, and both include: an entrance pupil grating unit, a pupil expansion grating unit and an exit pupil grating unit.
The two-color AR diffraction waveguide according to claim 13, wherein the left waveguide plate and the right waveguide plate form an obtuse angle at the connection point, with the inside of the obtuse angle being the inner side of the waveguide plate assembly, and the outside of the obtuse angle being The outside of the waveguide assembly; the input light of the waveguide assembly is injected into the entrance pupil grating unit from the outside, passes through the pupil expansion grating unit, and is emitted from the exit pupil grating unit. The exit pupil grating unit The direction of the emitted light is consistent with the direction of the incident light of the entrance pupil grating unit.
AR glasses, characterized by using the two-color AR diffraction waveguide according to any one of claims 1 to 14.
A kind of AR glasses with a single projector for 3D imaging, which is characterized by including: a projector, a waveguide lens, a coupling grating, a first light path turning grating, a first coupling grating, a second light path turning grating, and a second coupling grating. , a first liquid crystal light switch, a second liquid crystal light switch and a controller.
The single-projector 3D imaging AR glasses according to claim 16, wherein the waveguide lens includes a left eye area, a right eye area and a nose top area connecting the left eye area and the right eye area, The coupling grating is arranged in the nose top area, the first light path turning grating and the first coupling grating are arranged in the left eye area, the second light path turning grating and the second light path turning grating are arranged in the left eye area. The coupling grating is arranged in the right eye area, and a first image light path is formed between the coupling grating, the first light path turning grating and the first coupling grating, and the coupling grating, the first light path turning grating and the first coupling grating form A second image light path is formed between the two-light-path turning grating and the second coupling-out grating, and the projector is arranged toward the coupling-in grating.
The single-projector 3D imaging AR glasses according to claim 16, wherein the first liquid crystal light switch is disposed on the first image between the coupling grating and the first light path turning grating. On the optical path, the second liquid crystal optical switch is arranged on the second image optical path between the coupling grating and the second optical path turning grating; or the first liquid crystal optical switch is arranged on the first The side of the coupling-out grating faces the human eye, and the second liquid crystal light switch is disposed on the side of the second coupling-out grating facing the human eye.
The single-projector 3D imaging AR glasses according to claim 16, characterized in that the controller is connected to the projector, the first liquid crystal light switch and the second liquid crystal light switch, and the control The device is used to control the first liquid crystal light switch to turn on and the second liquid crystal light switch to turn off when the projector outputs an odd-numbered frame image, and to control the third liquid crystal light switch when the projector outputs an even-numbered frame image. One liquid crystal light switch is turned off, and the second liquid crystal light switch is turned on.
The single-projector 3D imaging AR glasses according to claim 16, characterized in that the AR glasses further include a visual correction system, and the visual correction system includes a first wedge-shaped lens group and a second wedge-shaped lens group.
The single-projector 3D imaging AR glasses according to claim 20, wherein the first wedge-shaped lens group includes The left outer wedge-shaped lens of the eye and the left inner wedge-shaped lens close to the human eye, the left outer wedge-shaped lens and the left inner wedge-shaped lens cover the exit pupil area placed on the left side of the entrance pupil area, and the The optical waveguide sheet is included between the left outer wedge-shaped lens and the left inner wedge-shaped lens, and the projection centers of the left outer wedge-shaped lens and the left inner wedge-shaped lens on the optical waveguide sheet coincide with each other; The second wedge-shaped lens group includes a right outer wedge-shaped lens away from the human eye and a right inner wedge-shaped lens close to the human eye. The right outer wedge-shaped lens and the right inner wedge-shaped lens cover and are placed on the right side of the entrance pupil area. The exit pupil area of the right side, and the optical waveguide plate is included between the right outer wedge lens and the right inner wedge lens, and the right outer wedge lens and the right inner wedge lens are in the optical waveguide. The projection centers on the waveguide plate coincide with each other.
The single-projector 3D imaging AR glasses according to claim 20, characterized in that the left inner wedge lens and the right inner wedge lens correct the outgoing beam vertically emitted by the two-way waveguide model into a deflected beam, so as to The image sources are overlapped at the target position to form an object image, and the left outer wedge-shaped lens and the right outer wedge-shaped lens respond to the external light generated by the left inner wedge-shaped lens and the right inner wedge-shaped lens. The light deflection is compensated; the left outer wedge-shaped lens, the left inner wedge-shaped lens, the right outer wedge-shaped lens, and the right inner wedge-shaped lens all include a far corner end and a near corner end, wherein the wedge-shaped lens The thickness of the far end of the wedge lens is greater than that of the proximal end of the wedge lens; the distal end of the left outer wedge lens and the distal end of the right outer wedge lens are close to the entrance pupil area; the far end of the left inner wedge lens The corner end and the far corner end of the right inner wedge-shaped lens are away from the entrance pupil area; in the first wedge-shaped lens group, the far corner end of the left outer wedge-shaped lens and the left inner wedge-shaped lens are The proximal end of the left outer wedge-shaped lens is opposite to the distal end of the left inner wedge-shaped lens. In the second wedge-shaped lens group, the distal end of the right outer wedge-shaped lens is opposite to the distal end of the left inner wedge-shaped lens. The proximal end of the right outer wedge lens is opposite to the proximal end of the right inner wedge lens, and the proximal end of the right outer wedge lens is opposite to the far end of the right inner wedge lens.
The single-projector 3D imaging AR glasses according to claim 22, characterized in that the left inner wedge lens and the right inner wedge lens correct the vertically emitted outgoing beam of the two-way waveguide model into a deflected beam. , so that the image sources overlap at the target position to form an object image, including: calculating the deflection of the exit beam by the left inner wedge-shaped lens and the right inner wedge-shaped lens according to the human eye pupil distance and arc length formulas Angle; obtain the wedge angle of the left outer wedge-shaped lens, the left inner wedge-shaped lens, the right outer wedge-shaped lens, and the right inner wedge-shaped lens according to the deflection angle, the formula is:

Among them, α is the deflection angle, θ is the wedge angle, n1 is the refractive index of the wedge lens material, and n2 is the refractive index of the medium where the wedge lens is located.