Double-coupling-in binocular ar display apparatus having single low-light engine

Abstract

A double-coupling-in binocular AR display apparatus having a single low-light engine (P0), comprising the low-light engine (P0) and a diffractive optical waveguide unit (P1), wherein the low-light engine (P0) comprises a low-light machine (P01), a block prism (P02) and a turning prism (P03); and the diffractive optical waveguide unit (P1) comprises a waveguide plate (WG), a first grating unit and a second grating unit. The first grating unit comprises a first coupling-in unit (IG1) and a first expansion coupling-out unit (OE1), the second grating unit comprises a second coupling-in unit (IG2) and a second expansion coupling-out unit (OE2), and the coupling-in units (IG1, IG2) and the expansion coupling-out units (O1, OE2) are in one-to-one correspondence and attached to the waveguide plate (WG); the block prism (P02) is used for dividing an emergent light beam of the low-light machine (P01) into two beams to enter the coupling-in units (IG1, IG2) from different exit pupil surfaces; the coupling-in units (IG1, IG2) are used for coupling received light beams into the waveguide plate (WG) and then transmitting the light beams to the corresponding expansion coupling-out units (OE1, OE2); and the expansion coupling-out units (OE1, OE2) are used for expanding the received light beams and then coupling the expanded light beams to human eyes. The apparatus can improve the coupling-in efficiency, thereby improving the overall brightness, and grating lines in each region have a larger range angle, such that more compact layout is achieved.

Description

A single micro-light engine dual-coupled binocular AR display device Technical Field

[0001] The present invention belongs to the field of near-eye display technology, and particularly relates to a single-micro-light engine dual-input binocular AR display device. Background Art

[0002] AR glasses consist of two parts: a microlight engine and an optical waveguide. The microlight engine can provide polarized or unpolarized images for the optical waveguide. Diffraction optical waveguides are currently the mainstream solution for AR glasses because they are thin (0.3mm~1mm), have high light transmittance (>80%), have a large eye movement range (>10×8mm), a large interocular distance (>15mm), and a large field of view. They can also be mastered using semiconductor processing technology and replicated in large quantities using nanoimprint technology, effectively reducing costs.

[0003] In the entire AR glasses, the cost of the micro-light engine accounts for a larger proportion than that of the optical waveguide, and its power consumption will also affect the use time of the AR glasses. Therefore, compared with the traditional AR glasses that require the use of two micro-light engines, the Chinese patent with publication number CN113219671A proposes an optical device and display device, which uses a single-light engine binocular AR glasses, which can achieve the effect of binocular imaging while using a single micro-light engine, and can effectively reduce the use cost of the entire AR glasses. Specifically, in order to achieve the effect of binocular imaging with a single micro-light engine, the solution only uses one entrance pupil grating unit, and by using its +1 level and -1 level, the light of the micro-light engine is coupled into the left pupil expansion grating unit and the right pupil expansion grating unit respectively, and then coupled out through the left exit pupil grating unit and the right exit pupil grating unit respectively after expansion. In order to ensure consistent imaging quality for the left and right eyes, it is necessary to ensure that the efficiency of the +1 and -1 orders generated by the entrance pupil grating unit is consistent. Therefore, a binary grating with a symmetrical structure but low efficiency must be used at the entrance pupil unit. At the same time, the grating vectors of the entrance pupil grating unit, the pupil expansion grating unit, and the out-coupling grating unit must be strictly restricted. For example, the grating vector of the entrance pupil grating unit is generally around 0° (-1°~1°), and the grating vector of the exit pupil grating unit is around 90° (88°~92°). The constraint of the grating vector limits the layout and appearance design of the optical waveguide, that is, the angular arrangement of the grating lines in each area is restricted, which is not conducive to achieving a more compact layout design. Summary of the Invention

[0004] The purpose of the present invention is to address the above-mentioned problems and propose a single micro-light engine dual-coupling binocular AR display device, which is conducive to improving the coupling efficiency, thereby increasing the overall brightness of the AR glasses, and can enable the grating lines in each area to have a wider range of angles, thereby achieving a more compact layout design.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] The present invention proposes a single micro-light engine dual-input binocular AR display device, comprising a micro-light engine and a diffraction light waveguide unit, wherein:

[0007] The microlight engine includes a microlight engine, a cubic prism, and a turning prism. The diffraction light waveguide unit includes a waveguide plate, a first grating unit, and a second grating unit. The first grating unit includes a first coupling unit and a first extended coupling unit. The second grating unit includes a second coupling unit and a second extended coupling unit. Each coupling unit and the extended coupling unit correspond to each other and are attached to the waveguide plate.

[0008] The cubic prism is used to split the output light beam of the micro-optical machine into two beams, one beam is deflected in the transmission direction by the turning prism and then emitted from the exit pupil surface of the turning prism to enter the first coupling unit, and the other beam is deflected in the transmission direction by the cubic prism and then emitted from the exit pupil surface of the cubic prism to enter the second coupling unit;

[0009] Each coupling-in unit is used to couple the received light beam into the waveguide plate for total reflection and then transmit it to the corresponding extended coupling-out unit;

[0010] Each expansion and coupling unit corresponds to a human eye one by one and is used to expand the received light beam and couple it out to the human eye;

[0011] The single-microlight engine dual-coupled binocular AR display device also meets the following conditions:

[0012] , , ;

[0013] Wherein, D is the diameter of the first coupling unit or the second coupling unit, D1 is the center distance between the first coupling unit and the second coupling unit, D2 is the center distance between the first extended coupling unit and the second extended coupling unit, and D3 is the center distance between the corresponding coupling unit and the extended coupling unit in the Y direction, where the Y direction is the up-down direction when worn on the human body.

[0014] Preferably, the first extended outcoupling unit includes a first extended unit and a first outcoupling unit, and the second extended outcoupling unit includes a second extended unit and a second outcoupling unit, each extended unit is used to expand the light beam coupled into the waveguide plate by the corresponding coupling unit and then transmit it to the corresponding outcoupling unit, and each outcoupling unit is used to couple the light beam received after expansion by the corresponding extended unit to the human eye;

[0015] The single-microlight engine dual-coupled binocular AR display device also meets the following conditions:

[0016] , , ;

[0017] Among them, Angle1 is the angle between the grating line direction used by the first coupling unit or the second coupling unit and the Y direction, Angle2 is the angle between the grating line direction used by the first expansion unit or the second expansion unit and the Y direction, and Angle3 is the angle between the grating line direction used by the first coupling unit or the second coupling unit and the Y direction.

[0018] Preferably, the grating vector of each grating unit also satisfies the following conditions:

[0019] 1) In the X direction: ;

[0020] 2) In the Y direction: + ;

[0021] Among them, M1 is the order used by the corresponding coupling unit, M2 is the order used by the corresponding expansion unit, M3 is the order used by the corresponding coupling unit, T1 is the period of the corresponding coupling unit, T2 is the period of the corresponding expansion unit, T3 is the period of the corresponding coupling unit, and the X direction is the left and right direction when worn on the human body.

[0022] Preferably, the first extended outcoupling unit and the second extended outcoupling unit are both two-dimensional gratings.

[0023] Preferably, the exit pupil surfaces of the turning prism and the cubic prism are both provided with polarization elements, and the polarization elements are circular polarizers or quarter-wave plates.

[0024] Preferably, the diameter D of the first coupling unit and the second coupling unit is 2.5 mm to 5 mm.

[0025] Preferably, the waveguide plate has a first surface and a second surface opposite to each other, each grating unit is located on the first surface or the second surface of the waveguide plate, and the micro light engine is located on the same side or different side of the waveguide plate as the grating unit and the human eye.

[0026] Preferably, the first coupling unit and the second coupling unit are surface relief gratings or volume holographic gratings.

[0027] Preferably, the micro optical engine is one of a MicroLED optical engine, a DLP optical engine, an LCOS optical engine, and an LBS optical engine.

[0028] Preferably, the cubic prism is a beam splitter prism, and the turning prism is a right-angle turning prism.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] Compared with the single micro-light engine and single-coupled binocular AR glasses in the existing technology, it is necessary to ensure that the grating used in the coupling unit is a binary grating so that the T+1 and T-1 used by the left and right eyes have the same diffraction efficiency. Therefore, the coupling unit must use a binary grating with a symmetrical structure but lower efficiency. In addition, it is necessary to ensure that the grating line directions of the coupling unit and the extended coupling unit are subject to very strict restrictions, such as the constraints on the grating vector, which limits the layout and appearance design of the optical waveguide, and is not conducive to the construction of a compact diffraction waveguide structure. The present application adopts a single micro-light engine and dual coupling method. Through structural improvement, the light beam emitted by the micro-light engine P01 is divided into two beams, so that the micro-light engine P0 can provide two exit pupils for the diffraction light waveguide unit P1, and cooperate with the diffraction light waveguide unit P1 to achieve dual coupling, thereby enabling independent adjustment design of the first grating unit and the second grating unit, which is more flexible and free in layout, and allows the coupling unit to use a grating with higher diffraction efficiency to improve the coupling efficiency, thereby improving the overall brightness of the AR glasses. Moreover, since there are two independent coupling units, the grating lines in each area can have a wider range of angles, which is conducive to a more compact layout design and meets the needs of people with different pupil distances. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG1 is a schematic diagram of the first viewing angle structure of a single micro-light engine dual-coupled binocular AR display device according to embodiment 1 of the present invention;

[0032] FIG2 is a schematic structural diagram of a micro light engine according to embodiment 1 of the present invention;

[0033] FIG3 is a schematic structural diagram of a diffraction optical waveguide unit according to embodiment 1 of the present invention;

[0034] FIG4 is a schematic diagram showing the angle between the grating lines used in the coupling unit and the Y direction in Example 1 of the present invention;

[0035] FIG5 is a schematic diagram of the angle between the grating lines used in the expansion unit of Example 1 of the present invention and the Y direction;

[0036] FIG6 is a schematic diagram of the angle between the grating lines used in the outcoupling unit and the Y direction in Example 1 of the present invention;

[0037] FIG7 is a schematic diagram of the second viewing angle structure of the single micro-light engine dual-coupled binocular AR display device according to embodiment 1 of the present invention;

[0038] FIG8 is a schematic diagram of the layout of the micro-light engine, diffraction optical waveguide unit and human eye of the present invention;

[0039] FIG9 is a schematic structural diagram of a diffraction optical waveguide unit according to embodiment 2 of the present invention.

[0040] Explanation of the reference numerals: P0, micro-light engine; P1, diffraction optical waveguide unit; WG, waveguide plate; OE1, first extended out-coupling unit; OE2, second extended out-coupling unit; IG1, first coupling unit; IG2, second coupling unit; EG1, first extended unit; EG2, second extended unit; OG1, first out-coupling unit; OG2, second out-coupling unit; L1, first surface; L2, second surface; P01, micro-light engine; P02, cubic prism; P03, turning prism; EX1, exit pupil surface of turning prism; EX2, exit pupil surface of cubic prism. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0042] It should be noted that, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art in the art of this application. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. Example 1

[0043] As shown in FIG1-8 , a single-micro-light engine dual-input binocular AR display device includes a micro-light engine P0 and a diffraction light waveguide unit P1, wherein:

[0044] The microlight engine P0 includes a microlight engine P01, a cubic prism P02, and a turning prism P03. The diffraction light waveguide unit P1 includes a waveguide plate WG, a first grating unit, and a second grating unit. The first grating unit includes a first coupling unit IG1 and a first extended coupling unit OE1. The second grating unit includes a second coupling unit IG2 and a second extended coupling unit OE2. Each coupling unit and extended coupling unit corresponds to each other and are attached to the waveguide plate WG.

[0045] The cubic prism P02 is used to split the output light beam of the micro-optical machine P01 into two beams. One beam is deflected in the transmission direction by the turning prism P03 and then emitted from the exit pupil surface EX1 of the turning prism to enter the first coupling unit IG1. The other beam is deflected in the transmission direction by the cubic prism P02 and then emitted from the exit pupil surface EX2 of the cubic prism to enter the second coupling unit IG2.

[0046] Each coupling unit is used to couple the received light beam into the waveguide plate WG for total reflection and then transmit it to the corresponding extended coupling unit;

[0047] Each expansion and coupling unit corresponds to a human eye one by one and is used to expand the received light beam and couple it out to the human eye;

[0048] The single-microlight engine dual-coupled binocular AR display device also meets the following conditions:

[0049] , , ;

[0050] Wherein, D is the diameter of the first coupling unit IG1 or the second coupling unit IG2, D1 is the center distance between the first coupling unit IG1 and the second coupling unit IG2, D2 is the center distance between the first extended coupling unit OE1 and the second extended coupling unit OE2, and D3 is the center distance between the corresponding coupling unit and the extended coupling unit in the Y direction, where the Y direction is the up-down direction when worn on the human body.

[0051] For ease of explanation, in this application, the X direction refers to the left-right direction of the binocular AR display device when worn on a person, the Y direction refers to the up-down direction of the binocular AR display device when worn on a person, and the Z direction refers to the front-back direction of the binocular AR display device when worn on a person. The specific directions can be adjusted by those skilled in the art according to actual needs and are not limited.

[0052] As shown in Figure 1, the single-microlight engine dual-coupled binocular AR display device includes a microlight engine P0 and a diffractive light waveguide unit P1. Specifically, the microlight engine P0 includes a microlight engine P01, a cubic prism P02, and a turning prism P03, as shown in Figure 2. The microlight engine P01 can provide images with high brightness, high uniformity, and high imaging quality. The cubic prism P02 can split the light beam emitted by the microlight engine P01 into two beams according to a desired ratio or requirement, such as a 1:1 ratio. One beam reaches the turning prism P03. If it is a right-angle turning prism, its transmission direction is deflected 90° before it is emitted from the exit pupil surface EX1 of the turning prism. The other beam is deflected 90° in the cubic prism P02 before it is emitted from the exit pupil surface EX2 of the cubic prism. The use of the microlight engine P0 can provide two exit pupils, EX1 and EX2, for the diffractive light waveguide unit P1.

[0053] The diffraction light waveguide unit P1 comprises a waveguide plate WG, a first grating unit, a second coupling unit IG2, and a second grating unit. The waveguide plate WG offers advantages such as lightness, high light transmittance, a wide eye movement range, a wide interocular distance, and a wide field of view. The first coupling unit IG1 and the second coupling unit IG2 correspond to the exit pupil surfaces EX1 and EX2 of the turning prism, respectively. Light beams exiting the exit pupil surface EX1 of the turning prism enter the first coupling unit IG1, while light beams exiting the exit pupil surface EX2 of the cubic prism enter the second coupling unit IG2. The first coupling unit IG1 couples the received light beam into the waveguide plate WG for total internal reflection, which then transmits it to the first expansion coupling unit OE1. The second coupling unit IG2 couples the received light beam into the waveguide plate WG for total internal reflection, which then transmits it to the second expansion coupling unit OE2. The first and second expansion coupling units OE1 and OE2 correspond to the left and right eyes, respectively, and expand the received light beams before coupling them out to the eyes. By reasonably setting the parameters of the center distance D1 between the first coupling unit IG1 and the second coupling unit IG2, the center distance D2 between the first extended coupling unit OE1 and the second extended coupling unit OE2, and the center distance D3 in the Y direction between the first coupling unit IG1 and the first extended coupling unit OE1 or the second coupling unit IG2 and the second extended coupling unit OE2, it helps to control the sizes of the first coupling unit IG1 and the second coupling unit IG2, and enables the AR display device to meet the needs of people with different pupil distances.

[0054] Compared with the single micro-light engine and single-coupled binocular AR glasses in the existing technology, it is necessary to ensure that the grating used in the coupling unit is a binary grating so that the T+1 and T-1 used by the left and right eyes have the same diffraction efficiency. Therefore, the coupling unit must use a binary grating with a symmetrical structure but lower efficiency. In addition, it is necessary to ensure that the grating line directions of the coupling unit and the extended coupling unit are subject to very strict restrictions, such as the constraints on the grating vector, which limits the layout and appearance design of the optical waveguide, and is not conducive to the construction of a compact diffraction waveguide structure. The present application adopts a single micro-light engine and dual coupling approach. Through structural improvement, the light beam emitted by the micro-light engine P01 is divided into two beams, so that the micro-light engine P0 can provide two exit pupils for the diffraction light waveguide unit P1, and cooperate with the diffraction light waveguide unit P1 to achieve dual coupling, thereby enabling independent adjustment design of the first grating unit and the second grating unit, which is more flexible and free in layout, and allows the coupling unit to use a grating with higher diffraction efficiency (such as a tilted grating or a blazed grating) instead of a binary grating with a symmetrical structure but lower efficiency, so as to improve the coupling efficiency and thereby improve the overall brightness of the AR glasses. Moreover, since there are two independent coupling units, the grating lines in each region can have a wider range of angles, which is conducive to a more compact layout design.

[0055] In one embodiment, the first extended outcoupling unit OE1 includes a first extended unit EG1 and a first outcoupling unit OG1, and the second extended outcoupling unit OE2 includes a second extended unit EG2 and a second outcoupling unit OG2. Each extended unit is configured to expand a light beam coupled into the waveguide plate WG by a corresponding coupling unit and transmit the expanded light beam to a corresponding outcoupling unit. Each outcoupling unit is configured to couple the expanded light beam received by the corresponding extended unit out to a human eye.

[0056] The single-microlight engine dual-coupled binocular AR display device also meets the following conditions:

[0057] , , ;

[0058] Among them, Angle1 is the angle between the grating line direction used by the first coupling unit IG1 or the second coupling unit IG2 and the Y direction, Angle2 is the angle between the grating line direction used by the first expansion unit EG1 or the second expansion unit EG2 and the Y direction, and Angle3 is the angle between the grating line direction used by the first outcoupling unit OG1 or the second outcoupling unit OG2 and the Y direction.

[0059] As shown in FIG3 , the first extended outcoupling unit OE1 and the second extended outcoupling unit OE2 of the dual-input diffraction optical waveguide unit P1 used in this embodiment each comprise separate extension and outcoupling elements. Specifically, the first extended outcoupling unit OE1 comprises a first extended unit EG1 and a first outcoupling unit OG1, while the second extended outcoupling unit OE2 comprises a second extended unit EG2 and a second outcoupling unit OG2. The first extended unit EG1, the first outcoupling unit OG1, the second extended unit EG2, and the second outcoupling unit OG2 are all attached to the waveguide plate WG. The first extended unit EG1 and the second extended unit EG2 can be one-dimensional gratings, such as rectangular gratings, blazed gratings, tilted gratings, and holographic gratings. The first outcoupling unit OG1 and the second outcoupling unit OG2 can be one-dimensional or two-dimensional gratings. The one-dimensional grating type is the same as the extended unit, while the two-dimensional grating can be any shape with periodic variations in the X and Y directions, such as a cylindrical grating, a cross grating, or a polygonal grating. By using a single micro-light engine and dual-incoupling layout, the grating line directions of the incoupling unit, expansion unit, and outcoupling unit can vary over a wider range, as shown in Figures 4, 5, and 6. By properly setting the angle ranges of Angle1, Angle2, and Angle3, flexibility in layout and period selection of each region can be ensured, avoiding interference between the expansion region and the outcoupling region. While maintaining the display effect, the layout of each region can be more flexible, the period can be adjusted within a wider range, and the overall size of the waveguide plate can be more compact.

[0060] In one embodiment, the raster vectors of each raster unit further satisfy the following conditions:

[0061] 1) In the X direction: ;

[0062] 2) In the Y direction: + ;

[0063] Among them, M1 is the order used by the corresponding coupling unit, M2 is the order used by the corresponding expansion unit, M3 is the order used by the corresponding coupling unit, T1 is the period of the corresponding coupling unit, T2 is the period of the corresponding expansion unit, T3 is the period of the corresponding coupling unit, and the X direction is the left and right direction when worn on the human body.

[0064] The sum of the grating vectors of each grating unit is zero. By utilizing multiple gratings in the corresponding coupling unit, expansion unit, and coupling unit to change the beam path and deflect the light path, a smaller layout is achieved while ensuring the effective propagation of the field of view (FOV) within the waveguide plate WG. M1, M2, and M3 can all be -1 or +1 orders. Furthermore, each grating unit is independent and does not affect each other, allowing the period, direction, and order of each grating unit to be freely adjustable, i.e., the same or different. The layout and design are flexible and easy to adjust to meet design requirements, thereby improving the coupling efficiency and, in turn, the overall brightness of the AR glasses.

[0065] In one embodiment, both the exit pupil surface EX1 of the turning prism and the exit pupil surface EX2 of the cubic prism are provided with polarization elements, and the polarization elements are circular polarizers or quarter-wave plates.

[0066] Polarization elements, such as circular polarizers or quarter-wave plates, are placed on the two exit pupil surfaces to eliminate ghost images caused by reflections between the microlight engine P0 and the diffractive waveguide unit P1. Preferably, the exit pupil surface EX1 of the turning prism and the exit pupil surface EX2 of the cubic prism are coplanar, i.e., they are at the same distance from the corresponding coupling units.

[0067] In one embodiment, the diameter D of the first coupling unit IG1 and the second coupling unit IG2 is 2.5 mm to 5 mm, which can completely collect the light beam emitted by the micro-optical machine into the waveguide plate WG and is suitable for the exit pupil diameters of different types of micro-optical machines.

[0068] In one embodiment, the waveguide plate WG has a first surface L1 and a second surface L2 opposite to each other. Each grating unit is located on the first surface L1 or the second surface L2 of the waveguide plate WG. The micro light engine P0 is located on the same side or on the opposite side of the waveguide plate WG as the grating unit and the human eye.

[0069] As shown in FIG7 , the waveguide plate WG has a first surface L1 and a second surface L2 that are arranged opposite to each other. The microlight engine P0, the grating unit, and the human eye can be positioned arbitrarily relative to the waveguide plate WG. For example, the microlight engine P0 and the grating unit can be positioned on the same side of the waveguide plate WG, such as the side where the first surface L1 is located or the side where the second surface L2 is located, or on opposite sides of the waveguide plate WG, such as the side where the first surface L1 is located or the side where the second surface L2 is located. Similarly, the microlight engine P0 and the human eye can be positioned on the same side of the waveguide plate WG, such as the side where the first surface L1 is located or the side where the second surface L2 is located, or on opposite sides of the waveguide plate WG, such as the side where the first surface L1 is located or the side where the second surface L2 is located. Specifically, as shown in FIG8( a ), the microlight engine P0, the grating unit, and the human eye are all located on the side where the second surface L2 of the waveguide plate WG is located (i.e., the side close to the human face when worn), and the microlight engine P0 and the human eye are kept on the same side; as shown in FIG8( b ), the microlight engine P0 is located on the side where the first surface L1 of the waveguide plate WG is located (i.e., the side away from the human face when worn), and the grating unit and the human eye are both located on the side where the second surface L2 of the waveguide plate WG is located (i.e., the side close to the human face when worn), and the microlight engine P0 and the human eye are kept on different sides. The specific adjustment can also be made according to actual needs.

[0070] In one embodiment, the first coupling unit IG1 and the second coupling unit IG2 are surface relief gratings or volume holographic gratings.

[0071] In one embodiment, the micro optical engine P01 is a MicroLED optical engine, a DLP optical engine, an LCOS optical engine, or an LBS optical engine. Alternatively, other optical engines known to those skilled in the art may be selected based on actual needs.

[0072] In one embodiment, the cubic prism P02 is a beam splitter prism, and the turning prism P03 is a right-angle turning prism. The beam splitter prism can split the output light beam of the micro-optical machine P01 into two beams in a ratio, such as a 1:1 beam splitting. Alternatively, the beam splitter prism can also be a polarization beam splitter prism to split the output light beam of the micro-optical machine P01 into two beams according to the polarization state, such as into P light and S light.

[0073] Example 2:

[0074] A single micro-light engine dual-coupled binocular AR display device is based on Example 1, with the following differences:

[0075] In this embodiment, both the first extended outcoupling unit OE1 and the second extended outcoupling unit OE2 are two-dimensional gratings. As shown in Figure 9, the first extended outcoupling unit OE1 and the second extended outcoupling unit OE2 (equivalent to combining the extension unit and the outcoupling unit in Example 1 into a single component) achieve expansion in the X and Y directions and can couple the image out of the waveguide plate WG, resulting in a more compact structure. The sum of the grating vectors of each grating unit is zero. Each coupling-in unit utilizes a one-dimensional grating, such as a tilted grating or a blazed grating, while each extended outcoupling unit utilizes a two-dimensional grating, such as a cross grating, a cylindrical grating, or other two-dimensional grating capable of achieving expansion in the X and Y directions and coupling the image out of the waveguide plate WG. D1, D2, and D3 satisfy the corresponding equations of Example 1.

[0076] Compared with the single micro-light engine and single-coupled binocular AR glasses in the existing technology, it is necessary to ensure that the grating used in the coupling unit is a binary grating so that the T+1 and T-1 used by the left and right eyes have the same diffraction efficiency. Therefore, the coupling unit must use a binary grating with a symmetrical structure but lower efficiency. In addition, it is necessary to ensure that the grating line directions of the coupling unit and the extended coupling unit are subject to very strict restrictions, such as the constraints on the grating vector, which limits the layout and appearance design of the optical waveguide, and is not conducive to the construction of a compact diffraction waveguide structure. The present application adopts a single micro-light engine and dual coupling approach. Through structural improvement, the light beam emitted by the micro-light engine P01 is divided into two beams, so that the micro-light engine P0 can provide two exit pupils for the diffraction light waveguide unit P1, and cooperate with the diffraction light waveguide unit P1 to achieve dual coupling, thereby enabling independent adjustment design of the first grating unit and the second grating unit, which is more flexible and free in layout, and allows the coupling unit to use a grating with higher diffraction efficiency (such as a tilted grating or a blazed grating) instead of a binary grating with a symmetrical structure but lower efficiency, so as to improve the coupling efficiency and thereby improve the overall brightness of the AR glasses. Moreover, since there are two independent coupling units, the grating lines in each region can have a wider range of angles, which is conducive to a more compact layout design.

[0077] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] The above-described embodiments merely represent specific and detailed examples of the present application and should not be construed as limiting the scope of the patent application. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A single micro-light engine dual-coupled binocular AR display device, characterized in that: The single micro-light engine dual-coupled binocular AR display device comprises a micro-light engine (P0) and a diffraction light waveguide unit (P1), wherein: The micro light engine (P0) comprises a micro light engine (P01), a cubic prism (P02) and a turning prism (P03); the diffraction light waveguide unit (P1) comprises a waveguide plate (WG), a first grating unit and a second grating unit; the first grating unit comprises a first coupling unit (IG1) and a first extended coupling unit (OE1); the second grating unit comprises a second coupling unit (IG2) and a second extended coupling unit (OE2); each of the coupling units and the extended coupling units corresponds to each other and are attached to the waveguide plate (WG); The cubic prism (P02) is used to split the outgoing light beam of the micro-optical machine (P01) into two beams, one beam being deflected in the transmission direction by the turning prism (P03) and then emitted from the exit pupil surface (EX1) of the turning prism to enter the first coupling unit (IG1), and the other beam being deflected in the transmission direction in the cubic prism (P02) and then emitted from the exit pupil surface (EX2) of the cubic prism to enter the second coupling unit (IG2); Each of the coupling-in units is used to couple the received light beam into the waveguide plate (WG) for total reflection and then transmit the light beam to the corresponding extended coupling-out unit; Each of the expansion and coupling units corresponds to a human eye one by one, and is used to expand the received light beam and then couple it out to the human eye; The single micro-light engine dual-coupled binocular AR display device also meets the following conditions: ， ， ； Wherein, D is the diameter of the first coupling unit (IG1) or the second coupling unit (IG2), D1 is the center distance between the first coupling unit (IG1) and the second coupling unit (IG2), D2 is the center distance between the first extended coupling unit (OE1) and the second extended coupling unit (OE2), and D3 is the center distance between the corresponding coupling unit and the extended coupling unit in the Y direction, and the Y direction is the up and down direction when worn by the human body.

2. The single micro-light engine dual-coupled binocular AR display device according to claim 1, characterized in that: The first extended outcoupling unit (OE1) comprises a first extended unit (EG1) and a first outcoupling unit (OG1), and the second extended outcoupling unit (OE2) comprises a second extended unit (EG2) and a second outcoupling unit (OG2), each of the extended units is used to expand the light beam coupled into the waveguide plate (WG) by the corresponding coupling unit and transmit it to the corresponding outcoupling unit, and each of the outcoupling units is used to couple the received light beam expanded by the corresponding extended unit to the human eye; The single micro-light engine dual-coupled binocular AR display device also meets the following conditions: ， ， ； Wherein, Angle1 is the angle between the grating line direction used by the first coupling unit (IG1) or the second coupling unit (IG2) and the Y direction, Angle2 is the angle between the grating line direction used by the first extension unit (EG1) or the second extension unit (EG2) and the Y direction, and Angle3 is the angle between the grating line direction used by the first coupling unit (OG1) or the second coupling unit (OG2) and the Y direction.

3. The single micro-light engine dual-coupled binocular AR display device as claimed in claim 2, characterized in that: The grating vectors of each grating unit also satisfy the following conditions: 1) In the X direction: ； 2) In the Y direction: + ； Among them, M1 is the order used by the corresponding coupling unit, M2 is the order used by the corresponding extension unit, M3 is the order used by the corresponding coupling unit, T1 is the period corresponding to the coupling unit, T2 is the period corresponding to the extension unit, T3 is the period corresponding to the coupling unit, and the X direction is the left and right direction when worn by the human body.

4. The single micro-light engine dual-coupled binocular AR display device according to claim 1, wherein: The first extended outcoupling unit (OE1) and the second extended outcoupling unit (OE2) are both two-dimensional gratings.

5. The single micro-light engine dual-coupled binocular AR display device as claimed in claim 1, characterized in that: The exit pupil surface (EX1) of the turning prism and the exit pupil surface (EX2) of the cubic prism are both provided with polarization elements, and the polarization elements are circular polarizers or quarter-wave plates.

6. The single micro-light engine dual-coupled binocular AR display device as claimed in claim 1, characterized in that: The diameter D of the first coupling unit (IG1) and the second coupling unit (IG2) is 2.5 mm to 5 mm.

7. The single micro-light engine dual-coupled binocular AR display device as claimed in claim 1, characterized in that: The waveguide plate (WG) has a first surface (L1) and a second surface (L2) arranged opposite to each other, each of the grating units is located on the first surface (L1) or the second surface (L2) of the waveguide plate (WG), and the micro light engine (P0) is located on the same side or the opposite side of the waveguide plate (WG) as the grating unit and the human eye.

8. The single micro-light engine dual-coupled binocular AR display device as claimed in claim 1, characterized in that: The first coupling unit (IG1) and the second coupling unit (IG2) are surface relief gratings or volume holographic gratings.

9. The single micro-light engine dual-coupled binocular AR display device as claimed in claim 1, characterized in that: The micro optical machine (P01) is one of a Micro LED optical machine, a DLP optical machine, a LCOS optical machine, and a LBS optical machine.

10. The single micro-light engine dual-coupled binocular AR display device as claimed in claim 1, characterized in that: The cubic prism (P02) is a beam splitter prism, and the turning prism (P03) is a right-angle turning prism.

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