AR glasses

Abstract

The present invention provides an AR glasses, which utilizes a multi-light source pupil splitting technology. Two light sources are arranged at the light source position. The optical machine is an afocal system composed of two groups of lenses. The two light sources can respectively enter their respective images into a first coupling grating and a second coupling grating without overlapping. The two light sources emit light alternately. At the same time, a liquid crystal panel switches images continuously in coordination with the alternation of the two light sources, so that each light source corresponds to the left and right eye parallax images it carries. Finally, the first light source projects the left eye parallax image onto the first coupling grating and transmits it to the first coupling grating on the left side to enter the left eye of a person. The second light source projects the right eye parallax image onto the second coupling grating and transmits it to the second coupling grating on the right side to enter the right eye of a person. The alternating appearance of the two parallax images forms a 3D effect.

Description

Technical Field

[0001] The present invention relates to the field of virtual reality technology, and in particular to AR glasses. Background Art

[0002] With the advancement of imaging technology, people's demand for immersive experience is getting higher and higher. The development of VR / AR technology in recent years has gradually met 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 lightness are the main considerations. The near-eye display system is generally composed of an image far and near light transmission system. The image picture emitted by the image source is transmitted to the human eye through an optical transmission system. Here, unlike VR's blocking of the external environment, AR needs to have a certain transmittance so that the wearer can see the external environment while seeing the image picture.

[0003] Currently, most AR glasses from various manufacturers use a dual-projector configuration, which can control the images for the left and right eyes separately, thereby synthesizing a visual image with a 3D effect. However, the dual projector assembly process is complicated because the resulting image needs to be calibrated, which is time-consuming and has a low yield, making it difficult to mass produce.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] The present invention provides an AR glasses, aiming to solve the technical problems that the AR glasses using dual projectors have complicated assembly steps and inconvenient calibration.

[0006] The technical solution of the present invention is as follows:

[0007] AR glasses, comprising an optical machine part and a glasses part, wherein the glasses part comprises a waveguide lens, a first coupling grating, a first deflection grating, a first deflection grating, a first deflection grating, a second coupling grating, a second deflection grating, and a second deflection grating; the first coupling grating and the second coupling grating are arranged in a nose top area of ​​the waveguide lens and are separated from each other by the deflection grating;

[0008] The first turning grating and the first out-coupling grating are arranged in the left eye area of ​​the waveguide lens, and a first image light path is formed between the first coupling-in grating, the first turning grating and the first out-coupling grating; the second turning grating and the second out-coupling grating are arranged in the right eye area of ​​the waveguide lens, and a second image light path is formed between the second coupling-in grating, the second turning grating and the second out-coupling grating;

[0009] The optical machine part includes a first light source, a second light source, a liquid crystal panel, a beam splitter, a first lens group, a second lens group and a prism;

[0010] The first lens group and the second lens group are arranged on two adjacent side surfaces of the beam splitter, and the liquid crystal panel is arranged on the other side surface of the beam splitter opposite to the second lens group;

[0011] According to the propagation order of light, the rear focal plane of the first lens group and the front focal plane of the second lens group overlap at the liquid crystal panel after passing through the beam splitter, and the first light source and the second light source are arranged at the front focal plane position of the first lens group;

[0012] The light incident surface of the prism is arranged closely to the light exit surface of the second lens group, the light exit surface of the prism covers the first coupling grating, the barrier plate and the second coupling grating, and the rear focal plane of the second lens group is located at the plane where the first coupling grating and the second coupling grating are located after passing through the prism.

[0013] In an optional implementation manner of the present invention, the first light source and the second light source, as well as the first coupling-in grating and the second coupling-in grating are arranged on the left and right.

[0014] In an optional implementation manner of the present invention, the first light source and the second light source, as well as the first coupling-in grating and the second coupling-in grating are arranged vertically.

[0015] In an optional embodiment of the present invention, the prism is an isosceles right triangle prism.

[0016] In an optional embodiment of the present invention, the beam splitter is a polarization beam splitter.

[0017] In an optional embodiment of the present invention, the first coupling-in grating, the first steering grating, the first coupling-out grating, the second coupling-in grating, the second steering grating and the second coupling-out grating are all surface relief gratings or volume holographic gratings.

[0018] In an optional implementation of the present invention, the liquid crystal panel is a liquid crystal on silicon panel.

[0019] In an optional embodiment of the present invention, the first light source and the second light source are laser light sources or LED light sources.

[0020] The beneficial effects are as follows: the present invention provides an AR glasses, which utilizes the multi-light source pupil splitting technology, and sets two projection light sources at the light source position. The optical machine is an afocal system composed of two groups of lenses. The two light sources can respectively enter the first coupling grating and the second coupling grating of their respective images without overlapping. The two light sources emit light alternately, and at the same time, the liquid crystal panel switches the image continuously in coordination with the alternation of the two light sources, so that each light source corresponds to the left and right eye parallax images it carries. Finally, the first light source projects the left eye parallax image onto the first coupling grating and transmits it to the first coupling grating on the left to enter the left eye of the person. The second light source projects the right eye parallax image onto the second coupling grating and transmits it to the second coupling grating on the right to enter the right eye of the person. Finally, the alternating appearance of the two parallax images forms a 3D effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The figure is a schematic diagram of the structure of an AR glasses of the present invention.

[0022] Figure 2 It is a schematic structural diagram of a glasses part of the AR glasses of the present invention.

[0023] Figure 3 This is a schematic diagram of the structure of the optical-mechanical part of the AR glasses of the present invention.

[0024] Figure 4 Schematic diagram of the technical principle of the optical and mechanical part of the AR glasses of the present invention.

[0025] Figure 5 It is a schematic structural diagram of another eyeglass part of the AR glasses of the present invention.

[0026] Figure 6 Schematic diagram of the structure of another optical-mechanical part of the AR glasses of the present invention.

[0027] Figure 7 A schematic diagram of the optical path of the optical-mechanical part of the AR glasses of the present invention.

[0028] Figure 8 Schematic diagram of the optical path of another optical-mechanical part of the AR glasses of the present invention.

[0029] The figures are as follows:

[0030] 160-optical machine part; 170-lens part; 10-waveguide lens; 20-first coupling-in grating; 30-first steering grating; 40-first coupling-out grating; 50-blocking plate; 60-second coupling-in grating; 70-second steering grating; 80-second coupling-out grating; 90-first light source; 100-second light source; 110-liquid crystal panel; 120-beam splitter; 130-first lens group; 140-second lens group; 150-prism; 180-first liquid crystal switch; 190-second liquid crystal switch. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0032] See also Figure 1 The present invention provides an AR glasses, including an optical machine part 160 and a glasses part 170, see Figure 2 , the glasses part 170 includes a waveguide lens 10, a first coupling grating 20, a first turning grating 30, a first coupling grating 40, a barrier 50, a second coupling grating 60, a second turning grating 70 and a second coupling grating 80; the first coupling grating 20 and the second coupling grating 60 are arranged in the nose top area of ​​the waveguide lens 10 and are separated from each other by the barrier 50; the first turning grating 30 and the first coupling grating 40 are arranged in the left eye area of ​​the waveguide lens 10, and a first image light path is formed between the first coupling grating 20, the first turning grating 30 and the first coupling grating 40; the second turning grating 70 and the second coupling grating 80 are arranged in the right eye area of ​​the waveguide lens 10, and a second image light path is formed between the second coupling grating 60, the second turning grating 70 and the second coupling grating 80;

[0033] See also Figure 3 The optical machine part 160 includes a first light source 90, a second light source 100, a liquid crystal panel 110, a beam splitter 120, a first lens group 130, a second lens group 140 and a prism 150; the first lens group 130 and the second lens group 140 are arranged on two adjacent side surfaces of the beam splitter 120, and the liquid crystal panel 110 is arranged on the other side surface of the beam splitter 120 opposite to the second lens group 140;

[0034] According to the propagation order of light, the rear focal plane of the first lens group 130 and the front focal plane of the second lens group 140 overlap at the liquid crystal panel 110 after passing through the beam splitter 120, and the first light source 90 and the second light source 100 are arranged at the front focal plane position of the first lens group 130;

[0035] See also Figure 1The light incident surface of the prism 150 is arranged close to the light exit surface of the second prism group 140, and the light exit surface of the prism 150 covers the first coupling grating 20, the blocking plate 50 and the second coupling grating 60. The rear focal plane of the second lens group 140 is located at the plane where the first coupling grating 20 and the second coupling grating 60 are located after passing through the prism 150.

[0036] See also Figure 4 The rear focal plane of the first lens group 130 and the front focal plane of the second lens group 140 of the optical-mechanical part of the present invention coincide with each other, forming an afocal system, wherein the light source plane is located at the front focal plane of the first lens group 130, the liquid crystal panel 110 is located at the coincidence of the rear focal plane of the first lens group 130 and the front focal plane of the second prism 140, and the optical-mechanical exit pupil plane (the surface of the prism 150 in contact with the first coupling grating 20 and the second coupling grating 60) is located at the rear focal plane of the second lens group 140. In this system, since the light source and the liquid crystal panel 110 are respectively at the front and rear focal planes of the first lens group 130, each pixel on the liquid crystal panel 110 can be evenly illuminated. At the same time, the liquid crystal panel 110 is also located at the front focal plane of the second lens group 140. The second lens group 140 can collimate the light for each pixel on the liquid crystal panel 110 and form a beam waist at the exit pupil surface. The energy density of the light spot at this position is the largest and the area is the smallest, and each point contains all the information of the projected image. Therefore, as long as light passes through, the complete image information can be projected no matter how it is blocked. Blocking the exit pupil will only reduce the image brightness but will not block the image information.

[0037] On the basis of the above-mentioned afocal system, the present invention can set multiple (for example, 2) non-overlapping light sources on the front focal plane of the first lens group 130. According to the symmetry of the afocal system, each light source is symmetrically imaged on the exit pupil plane of the optical machine (i.e., the rear focal plane of the second lens group 140), and the symmetry center is the rear focus of the first lens group 130. The center interval between the object and the image is proportional to the center interval between the light emitting surfaces of the light source, and the magnification depends on the focal length of the second lens group 140, that is, Where β is the vertical axis magnification, f2 is the equivalent focal length of the second lens group 140, and f1 is the equivalent focal length of the first lens group 140. Similarly, the object image formed on the exit pupil plane is also the waist of the projection light beam, and each image point carries the complete information of the image of the liquid crystal panel 110. Of course, the present invention can also choose to set a light source on the front focal plane of the first lens group 130 and set a liquid crystal switch on the light exit surface of the prism 150 to achieve coupling each object image to different first coupling gratings 20 and second coupling gratings 60 respectively.

[0038] The present invention uses dual projection light sources to couple light beams to the two first coupling gratings 20 and the second coupling gratings 60. The two projection light sources are alternately lit, and the liquid crystal panel 110 alternately switches images with different directional parallaxes according to the lit light sources, and transmits the images alternately to the left and right eyes through the first coupling gratings 20 and the second coupling gratings 60, ultimately producing a 3D effect. Figure 2 and see Figure 3 In an optional embodiment of the present invention, the first light source 90 and the second light source 100, as well as the first coupling grating 20 and the second coupling grating 60 are arranged on the left and right.

[0039] See also Figure 5 and Figure 6 In an optional embodiment of the present invention, the first light source 90 and the second light source 100, as well as the first coupling grating 20 and the second coupling grating 60 are arranged up and down.

[0040] See also Figure 1 In an optional embodiment of the present invention, the prism 150 is an isosceles right triangle prism.

[0041] In an optional implementation of the present invention, the beam splitter 120 is a polarization beam splitter.

[0042] In an optional embodiment of the present invention, the first coupling-in grating 20, the first steering grating 30, the first coupling-out grating 40, the second coupling-in grating 60, the second steering grating 70 and the second coupling-out grating 80 are all surface relief gratings or volume holographic gratings.

[0043] In an optional implementation of the present invention, the liquid crystal panel 110 is a liquid crystal on silicon panel.

[0044] In an optional embodiment of the present invention, the first light source 90 and the second light source 100 are laser light sources or LED light sources.

[0045] Example 1

[0046] The waveguide lens 10 of the AR glasses of the present invention adopts a dual entrance pupil channel, but due to the use of a single projection optical machine, the dual entrance pupil channels (i.e., the first coupling grating 20 and the second coupling grating 60) need to be arranged closely at the geometric center of the waveguide lens 10. There is a barrier 50 (which can be composed of a black film) between the first coupling grating 20 and the second coupling grating 60 to absorb the light diffracted in the opposite direction of the entrance pupil light to prevent crosstalk. The first coupling grating 20 and the second coupling grating 60 can be symmetrically distributed left and right, or symmetrically distributed up and down, and the first steering grating 30 and the second steering grating 70 move according to the change of the position of the first coupling grating 20 and the second coupling grating 60 to ensure that the entrance pupil light can be correctly propagated to the pupil expansion position. The projection optical machine adopts an afocal system, the rear focal plane of the first lens group 130 coincides with the front focal plane of the second lens group 140, the light source plane is on the front focal plane of the first lens group 130, the liquid crystal panel 110 is located at the coincidence of the rear focal plane of the first lens group 130 and the front focal plane of the second lens group 140, and the exit pupil plane is on the rear focal plane of the second lens group 140.

[0047] See also Figure 7 In the structure of AR glasses, a double-angle design is adopted, and the specific optical path is as follows: a first light source 90 and a second light source 100 are arranged on the front focal plane of the first lens group 130, and the two light sources are arranged on both sides of the optical axis of the first lens group 130 respectively. The illumination light beam passes through the first lens group 130 and enters the beam splitter 120, allowing the s wave to be reflected to the liquid crystal panel 110, and propagates in the direction of the second lens group 140 after carrying the image information, and the projection light beam is at the exit pupil plane (that is, the rear focal plane of the second lens group 140). Since the liquid crystal panel 110 is located at the front focal plane of the second lens group 140, the second lens group 140 collimates and images all pixels on the liquid crystal panel 110, and the images of all pixels are concentrated at the beam waist position, so each point of the exit pupil surface light spot contains complete information of the image. After passing through the second lens group 140, the light beam enters the prism 150, which is an isosceles right-angled triangular prism. It only deflects the light path and does not have other effects on the light beam. After reflection, the image of the first light source 90 will be coupled into the first coupling grating 20, and the image of the second light source 100 will be coupled into the second coupling grating 60. When only the first light source 90 is lit, only the first coupling grating 40 can display an image on the AR glasses; when only the second light source 100 is lit, only the second coupling grating 80 can display an image on the AR glasses. When the liquid crystal panel 110 is lit with the first light source 90, an image containing the left eye parallax is loaded, and when the second light source 100 is lit, an image containing the right eye parallax is loaded, so that a single optical machine can control two parallax images, thereby producing a 3D effect.

[0048] Example 2

[0049] The waveguide lens of the AR glasses of the present invention adopts a dual entrance pupil channel, but due to the use of a single projection optical machine, the dual entrance pupil channels (i.e., the first coupling grating 20 and the second coupling grating 60) need to be arranged closely at the geometric center of the waveguide lens. There is a barrier plate 50 (which can be composed of a black film) between the first coupling grating 20 and the second coupling grating 60 to absorb the light diffracted in the opposite direction of the entrance pupil light to prevent crosstalk. The first coupling grating 20 and the second coupling grating 60 can be symmetrically distributed left and right, or symmetrically distributed up and down, and the first steering grating 30 and the second steering grating 70 move according to the change of the position of the first coupling grating 20 and the second coupling grating 60 to ensure that the entrance pupil light can be correctly propagated to the pupil expansion position.

[0050] The projection optical machine adopts an afocal system, the rear focal plane of the first lens group 130 coincides with the front focal plane of the second lens group 140, the light source plane is on the front focal plane of the first lens group 130, the liquid crystal panel 110 is located at the coincidence of the rear focal plane of the first lens group 130 and the front focal plane of the second lens group 140, and the exit pupil plane is on the rear focal plane of the second lens group 140.

[0051] See also Figure 8 In the structure of AR glasses, a double-angle design is adopted, and the specific optical path is as follows: a single light source is set in the front focal plane of the first lens group 130, and the light source is located on the optical axis of the first lens group 130. The illumination light beam passes through the first lens group 130 and enters the beam splitter, allowing the s wave to be reflected to the liquid crystal panel 110, and propagates in the direction of the second lens group 140 after carrying the image information, and the projection light beam is at the exit pupil plane (that is, at the rear focal plane of the second lens group 140). Since the liquid crystal panel 110 is located in the front focal plane of the second lens group 140, the second lens group 140 collimates and images all pixels on the liquid crystal panel 110, and the images of all pixels are concentrated at the beam waist position, so each point of the light spot on the exit pupil plane contains complete information of the image. After passing through the second lens group 140, the light beam enters the prism. The prism 150 is an isosceles right triangle prism, which only deflects the light path and does not have other effects on the light beam. After reflection, the image of the light source will be formed on the liquid crystal switch (including the first liquid crystal switch 180 and the second liquid crystal switch 190). The first side liquid crystal switch 180 is turned on, and the second side liquid crystal switch 190 is turned off. Half of the light beam is coupled to the first coupling grating 20 and the second coupling grating 60 and propagates to the exit pupil. According to the above introduction, half of the light beam also retains the complete information of the image; the first liquid crystal switch 180 is turned off, and the second liquid crystal switch 190 is turned on. Half of the light beam is coupled to the first coupling grating 20 and the second coupling grating 60 and propagates to the exit pupil. When the liquid crystal panel 110 is loaded with an image containing the left eye parallax when the first side liquid crystal switch 180 is turned on, and loaded with an image containing the right eye parallax when the second side liquid crystal switch 190 is turned on, it can realize the control of two parallax images by a single optical machine, thereby producing a 3D effect.

[0052] In summary, the present invention provides an AR glasses, which utilizes the multi-light source pupil splitting technology, and sets two projection light sources at the light source position. The optical machine is an afocal system composed of two groups of lenses. The two light sources can respectively enter the first coupling grating and the second coupling grating of their respective images without overlapping. The two light sources emit light alternately, and at the same time, the liquid crystal panel switches the image continuously in coordination with the alternation of the two light sources, so that each light source corresponds to the left and right eye parallax images it carries. Finally, the first light source projects the left eye parallax image onto the first coupling grating and transmits it to the first coupling grating on the left to enter the left eye of the person. The second light source projects the right eye parallax image onto the second coupling grating and transmits it to the second coupling grating on the right to enter the right eye of the person. Finally, the alternating appearance of the two parallax images forms a 3D effect.

[0053] Although the present invention has been disclosed as above in terms of preferred embodiments, the above preferred embodiments are not intended to limit the present invention. A person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined in the claims.

Claims

1. An AR glasses, comprising an optical machine part and a glasses part, characterized in that: The eyeglass part comprises a waveguide lens, a first coupling grating, a first deflection grating, a first deflection grating, a first deflection grating, a barrier, a second coupling grating, a second deflection grating, and a second deflection grating; the first coupling grating and the second coupling grating are arranged in the nose top area of ​​the waveguide lens and are separated from each other by the barrier; The first turning grating and the first out-coupling grating are arranged in the left eye area of ​​the waveguide lens, and a first image light path is formed between the first coupling-in grating, the first turning grating and the first out-coupling grating; the second turning grating and the second out-coupling grating are arranged in the right eye area of ​​the waveguide lens, and a second image light path is formed between the second coupling-in grating, the second turning grating and the second out-coupling grating; The optical machine part includes a first light source, a second light source, a liquid crystal panel, a beam splitter, a first lens group, a second lens group and a prism; The first lens group and the second lens group are arranged on two adjacent side surfaces of the beam splitter, and the liquid crystal panel is arranged on the other side surface of the beam splitter opposite to the second lens group; According to the propagation order of light, the rear focal plane of the first lens group and the front focal plane of the second lens group overlap at the liquid crystal panel after passing through the beam splitter, and the first light source and the second light source are arranged at the front focal plane position of the first lens group; The light incident surface of the prism is arranged closely to the light exit surface of the second lens group, the light exit surface of the prism covers the first coupling grating, the barrier plate and the second coupling grating, and the rear focal plane of the second lens group is located at the plane where the first coupling grating and the second coupling grating are located after passing through the prism.

2. The AR glasses according to claim 1, characterized in that: The first light source and the second light source, as well as the first coupling-in grating and the first coupling-in grating are arranged left to right.

3. The AR glasses according to claim 1, characterized in that: The first light source and the second light source, as well as the first coupling-in grating and the first coupling-in grating are arranged up and down.

4. The AR glasses according to claim 1, characterized in that: The prism is an isosceles right-angled triangular prism.

5. The AR glasses according to claim 1, characterized in that: The beam splitter is a polarization beam splitter.

6. The AR glasses according to claim 1, characterized in that: The first coupling-in grating, the first deflection grating, the first deflection grating, the second coupling-in grating, the second deflection grating and the second deflection grating are all surface relief gratings or volume holographic gratings.

7. The AR glasses according to claim 1, characterized in that: The liquid crystal panel is a liquid crystal on silicon panel.

8. The AR glasses according to claim 1, characterized in that: The first light source and the second light source are laser light sources or LED light sources.

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