Zero-order multiplexing single-optical-machine binocular display device

Abstract

The application discloses a zero-order multiplexing single-optical-machine binocular display device, which comprises a micro light machine, a first right-angle turning prism, a first coupling unit, a second coupling unit and a third coupling unit. The zero-order multiplexing single-optical-machine binocular display device adopts the cooperation among the light splitting prisms, the right-angle turning prisms, the coupling units and the waveguide plates, so that the T0 diffraction order light generated by the first coupling unit is divided into two parts with the same energy and enters the second right-angle turning prism and the third right-angle turning prism respectively, then the T+1 and T-1 diffraction order light or the R+1 and R-1 diffraction order light is generated under the action of the second coupling unit and the third coupling unit, and the full reflection transmission is carried out in the waveguide plate, then the light is coupled out through the coupling-out units and enters the left and right eyes, the effective utilization of the T0 diffraction order light generated by the first coupling unit is realized, and thus the utilization rate of the micro light machine is improved and the eye entrance brightness is increased.

Description

Technical Field

[0001] This invention belongs to the field of binocular displays, and specifically relates to a zero-level multiplexed single-optical-mechanical binocular display device. Background Technology

[0002] AR glasses consist of two parts: a micro-optomechanical system (MOS) and an optical waveguide. The MOS incorporates various display technologies, such as LCOS, DLP, Micro-LED, and LBS, and can provide polarized or unpolarized images, high brightness, high uniformity, and high imaging quality to the optical waveguide. The diffractive optical waveguide, on the other hand, is lightweight (0.3mm to 1mm), has high light transmittance (>80%), a large eye movement range (>10 x 8mm), a large interpupillary distance (>15mm), and a large field of view. Furthermore, it can be mass-produced using semiconductor processing technology for mastering and nanoimprint technology, thus effectively reducing costs and making it the mainstream solution in AR glasses today.

[0003] In the entire AR glasses, the cost of the micro-optical engine accounts for a larger proportion compared to the diffractive waveguide, and its power consumption also affects the usage time of the AR glasses. Therefore, compared to the traditional AR glasses that require two micro-optical engines, patent CN 113219671 A uses a single-optical-engine binocular AR glasses, which can achieve binocular imaging effect while using only one micro-optical engine, effectively reducing the overall cost of using AR glasses.

[0004] However, this solution has certain drawbacks, such as... Figure 1 As shown, incident light passing through entrance pupil grating unit j will generate three diffraction orders: T+1, T-1, and T0. The T+1 and T-1 diffraction orders satisfy the total internal reflection condition and can be transmitted through total internal reflection within waveguide i. They are then coupled out from waveguide i via the coupling unit and enter the human eye. The T0 diffraction order, however, directly enters the external environment through waveguide i, its energy being wasted. For incident light within a certain field of view, even with an optimized entrance pupil unit, the average diffraction efficiency of T+1 and T-1 will not exceed 20%, while the average diffraction efficiency of T0 is close to 60%. Because T0 cannot be utilized, the overall utilization efficiency of the optical engine is low, significantly reducing the brightness of the diffracted waveguide and the display effect. Summary of the Invention

[0005] The purpose of this invention is to address the problems raised in the background art by proposing a zero-level multiplexing single-optical-mechanical binocular display device.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] This invention proposes a zero-order multiplexing single-optical-mechanical binocular display device, comprising a micro-optical engine, a first right-angled bend prism, a first coupling unit, a second coupling unit, a third coupling unit, a waveguide plate, a beam splitter prism, a second right-angled bend prism and a third right-angled bend prism, a first coupling unit and a second coupling unit, wherein:

[0008] The micro-optical engine and the first coupling unit are respectively located on one side of the two right-angle faces of the first right-angle turning prism. The first coupling unit is set on the waveguide plate, and the first coupling unit, the waveguide plate and the beam splitter are arranged in sequence. The second coupling unit and the third coupling unit are both set on one side of the waveguide plate and are symmetrically distributed relative to the first coupling unit. They are located on the same side or opposite side of the waveguide plate to the first coupling unit. The first inclined surface near the waveguide plate and the fourth inclined surface away from the waveguide plate on the first diagonal of the beam splitter are coated with a semi-transparent and semi-reflective film layer and a high-reflective film layer in sequence. The second inclined surface near the waveguide plate and the third inclined surface away from the waveguide plate on the second diagonal of the beam splitter are coated with a semi-transparent and semi-reflective film layer and a high-reflective film layer in sequence. The second right-angle turning prism and the third right-angle turning prism are respectively located on both sides of the beam splitter. The first coupling unit and the second coupling unit are respectively set on the waveguide plate and are closer to the human eye on the side.

[0009] The light emitted from the micro-optomechanical system is reflected by the inclined surface of the first right-angled bend prism and enters the first coupling unit. The first coupling unit generates three diffraction orders: T0, T+1, and T-1. The light of the T+1 and T-1 diffraction orders enters the waveguide plate and is transmitted by total internal reflection within the waveguide plate. The light of the T0 diffraction order passes through the waveguide plate and enters the beam splitter. It is reflected sequentially by the first and second diagonals of the beam splitter and enters the second and third right-angled bend prisms. It is then reflected by the inclined surfaces of the second and third right-angled bend prisms, respectively, and under the action of the second and third coupling units, it generates light of the T+1 and T-1 diffraction orders, or light of the R+1 and R-1 diffraction orders, which are transmitted by total internal reflection within the waveguide plate. Finally, the light of the T+1 and T-1 diffraction orders, or light of the T+1, T-1, R+1, and R-1 diffraction orders, is coupled out to the human eye through the first and second coupling units.

[0010] Preferably, each coupling unit is an embossed grating or a volume Bragg grating, and the period of each coupling unit is 300nm to 500nm.

[0011] Preferably, when the first coupling unit, the second coupling unit, and the third coupling unit are located on the same side of the waveguide plate, the first coupling unit is a rectangular grating, the second coupling unit and the third coupling unit are blazed gratings, and the surface of the blazed grating is coated with a metal film layer.

[0012] Preferably, when the second and third coupling units are located on opposite sides of the waveguide plate relative to the first coupling unit, the first coupling unit is a rectangular grating, the second and third coupling units are tilted gratings, and the surface of the tilted gratings is coated with a high-refractive-index layer.

[0013] Preferably, the beam splitter is an X-CUBE beam combining prism, and its surface is coated with an anti-reflection film.

[0014] Preferably, the inclined surfaces of each right-angle turning prism are coated with a high-reflection film or a metal film, and both right-angle surfaces are coated with an anti-reflection film.

[0015] Preferably, the center of the first coupling unit and the center of the beam splitter form a first straight line, the center of the second coupling unit and the center of the second right-angle turning prism form a second straight line, and the center of the third coupling unit and the center of the third right-angle turning prism form a third straight line, and the first, second and third straight lines are all perpendicular to the waveguide plate.

[0016] Preferably, the diameters of the first coupling unit, the second coupling unit, and the third coupling unit satisfy D11 = D12 = D13 = 2mm to 6mm, where D11 is the diameter of the first coupling unit, D12 is the diameter of the second coupling unit, and D13 is the diameter of the third coupling unit. The distance between the center of the first coupling unit and the center of the second coupling unit on the straight line, and the distance between the center of the first coupling unit and the center of the third coupling unit on the straight line are both d, and satisfy (D11 / 2) ≤ d ≤ (D11 / 2) + 1. The straight line containing the center of each coupling unit is perpendicular to the waveguide plate.

[0017] Preferably, the center distance L between the first coupling unit and the second coupling unit satisfies: 58mm≤L≤70mm.

[0018] Preferably, the refractive index n of the beam splitter prism, the second right-angle bend prism, and the third right-angle bend prism is 1.5 to 2.0.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] This zero-order multiplexed single-optical-mechanism binocular display device employs the cooperation of a beam-splitting prism, various right-angle turning prisms, various coupling units, and a waveguide plate. This allows the T0 diffraction order light generated by the first coupling unit to be split into two parts of equal energy, which then enter the second and third right-angle turning prisms respectively. Under the action of the second and third coupling units, T+1 and T-1 diffraction order light, or R+1 and R-1 diffraction order light, are generated and transmitted through total internal reflection within the waveguide plate. After being coupled out by the coupling units, the light enters the left and right eyes, achieving effective utilization of the T0 diffraction order light generated by the first coupling unit. This improves the utilization rate of the micro-optical-mechanism and increases the brightness entering the eyes. Attached Figure Description

[0021] Figure 1 This is a structural diagram of the prior art of this invention;

[0022] Figure 2 This is a schematic diagram of one embodiment of the zero-level multiplexed single-optical-mechanical binocular display device of the present invention;

[0023] Figure 3 This is a schematic diagram of the light rays in one embodiment of the zero-level multiplexed single-optical-engine binocular display device of the present invention;

[0024] Figure 4 This is a schematic diagram of another embodiment of the zero-level multiplexed single-optical-mechanical binocular display device of the present invention;

[0025] Figure 5 This is a schematic diagram of the light rays in another embodiment of the zero-level multiplexed single-optical-engine binocular display device of the present invention.

[0026] Explanation of reference numerals in the attached figures: 1. Micro-optical engine; 2. First right-angled bend prism; 3. First coupling unit; 4. Second coupling unit; 5. Third coupling unit; 6. Waveguide plate; 7. Beam splitter prism; 8. Second right-angled bend prism; 9. Third right-angled bend prism; 10. First coupling unit; 11. Second coupling unit. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] It should be noted that when a component is referred to as being "connected" to another component, it can be directly connected to the other component or there may be an intervening component. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to limit the application.

[0029] like Figure 2-5 As shown, a zero-order multiplexing single-optical-mechanical binocular display device includes a micro-optical-mechanical unit 1, a first right-angled bend prism 2, a first coupling unit 3, a second coupling unit 4, a third coupling unit 5, a waveguide plate 6, a beam splitter prism 7, a second right-angled bend prism 8 and a third right-angled bend prism 9, a first output unit 10 and a second output unit 11, wherein:

[0030] The micro-optical engine 1 and the first coupling unit 3 are respectively located on one side of the two right-angle surfaces of the first right-angle turning prism 2. The first coupling unit 3 is set on the waveguide plate 6, and the first coupling unit 3, the waveguide plate 6 and the beam splitter 7 are arranged in sequence. The second coupling unit 4 and the third coupling unit 5 are both set on one side of the waveguide plate 6 and are symmetrically distributed relative to the first coupling unit 3. They are located on the same side or opposite side of the waveguide plate 6 to the first coupling unit 3. The first inclined surface near the waveguide plate 6 and the fourth inclined surface away from the waveguide plate 6 on the first diagonal of the beam splitter 7 are successively coated with a semi-transparent semi-reflective film layer and a high-reflective film layer. The second inclined surface near the waveguide plate 6 and the third inclined surface away from the waveguide plate 6 on the second diagonal of the beam splitter 7 are successively coated with a semi-transparent semi-reflective film layer and a high-reflective film layer. The second right-angle turning prism 8 and the third right-angle turning prism 9 are respectively located on both sides of the beam splitter prism 7. The first coupling unit 10 and the second coupling unit 11 are respectively set on the waveguide plate 6 and are close to the human eye on the side.

[0031] The light emitted from the micro-optomechanical unit 1 is reflected by the inclined surface of the first right-angle turning prism 2 and enters the first coupling unit 3. The first coupling unit 3 generates three diffraction orders: T0, T+1, and T-1. The light of the T+1 and T-1 diffraction orders enters the waveguide plate 6 and is transmitted by total internal reflection in the waveguide plate 6. The light of the T0 diffraction order passes through the waveguide plate 6 and enters the beam splitter prism 7. It is reflected sequentially by the first and second diagonals of the beam splitter prism 7 and enters the second right-angle turning prism 8 and the third right-angle turning prism 8. Prism 9 is then reflected by the inclined surfaces of the second right-angle turning prism 8 and the third right-angle turning prism 9, respectively, and under the action of the second coupling unit 4 and the third coupling unit 5, it generates light of diffraction order T+1 and T-1, or light of diffraction order R+1 and R-1, which is transmitted by total internal reflection in the waveguide plate 6. Finally, light of diffraction order T+1 and T-1, or light of diffraction order T+1, T-1, R+1 and R-1, is coupled out to the human eye through the first coupling unit 10 and the second coupling unit 11.

[0032] It should be noted that, with Figure 2 and Figure 4For example, the X-axis is defined to point to the left and the Z-axis to point to the top. The first right-angle turning prism 2 is located on the left side (i.e., the light-emitting side) of the micro-optomechanical system 1. The micro-optomechanical system 1 can be a DLP optical engine, a Micro-LED optical engine, or an LCOS optical engine, etc. In this embodiment, the waveguide plate 6 is a high-refractive-index wafer with a refractive index of 1.5 to 2.5 and a thickness of 0.3 to 1.5 mm. The first coupling unit 3 is disposed on the upper side of the waveguide plate 6, and the first coupling unit 3, the waveguide plate 6, and the beam splitter 7 are arranged sequentially from top to bottom. The second coupling unit 4 and the third coupling unit 5 are both disposed on one side of the waveguide plate 6 (such as the upper or lower side), and the second coupling unit 4 and the third coupling unit 5 are symmetrical to the first coupling unit 3. The second coupling unit 4 and the third coupling unit 5 are located on the same side or opposite side of the waveguide plate 6, opposite to the first coupling unit 3. One right-angle face of each of the second right-angle turning prism 8 and the third right-angle turning prism 9 is attached to the left and right sides of the beam splitter prism 7, and the other right-angle face of each is disposed close to the waveguide plate 6. The first coupling unit 10 and the second coupling unit 11 are both disposed on both sides of the waveguide plate 6, and correspond to the left and right eyes of a person, respectively.

[0033] A semi-transparent and semi-reflective coating layer and a high-reflective coating layer are sequentially deposited on the first inclined surface near the waveguide plate 6 and the fourth inclined surface away from the waveguide plate 6 on the first diagonal of the beam splitter 7, that is, the first inclined surface S01 and the fourth inclined surface S04 of the beam splitter 7 are sequentially deposited with a semi-transparent and semi-reflective coating layer and a high-reflective coating layer (or a metal film) on the second inclined surface near the waveguide plate 6 and the third inclined surface away from the waveguide plate 6 on the second diagonal of the beam splitter 7, that is, the second inclined surface S02 and the third inclined surface S03 of the beam splitter 7 are sequentially deposited with a semi-transparent and semi-reflective coating layer and a high-reflective coating layer (or a metal film).

[0034] The T+1 and T-1 diffraction order light generated by the first coupling unit 3 is transmitted by total internal reflection within the waveguide plate 6. The T+1 diffraction order light is transmitted by total internal reflection along the +X axis direction, and the T-1 diffraction order light is transmitted by total internal reflection along the -X axis direction. Finally, the light is coupled out from the first coupling unit 10 and the second coupling unit 11 in sequence and transmitted to the human eye.

[0035] In one embodiment, each coupling unit is an embossed grating or a volume holographic grating, and the period of each coupling unit is 300nm to 500nm.

[0036] In one embodiment, the beam splitter 7 is an X-CUBE beam combining prism, and its surface is coated with an anti-reflection film.

[0037] In one embodiment, the bevels of each right-angle prism are coated with a high-reflectivity film or a metal film, and both right-angle surfaces are coated with an anti-reflection film.

[0038] In one embodiment, the center of the first coupling unit 3 and the center of the beam splitter 7 form a first straight line, the center of the second coupling unit 4 and the center of the second right-angle turning prism 8 form a second straight line, and the center of the third coupling unit 5 and the center of the third right-angle turning prism 9 form a third straight line, and the first, second and third straight lines are all perpendicular to the waveguide plate 6.

[0039] It should be noted that, according to this embodiment, if the center position coordinates of the first coupling unit 3 are (X3, Y3) and the center position coordinates of the beam splitter 7 are (X7, Y7), then point (X3, Y3) coincides with point (X7, Y7); if the center position coordinates of the second coupling unit 4 are (X4, Y4) and the center position coordinates of the second right-angle turning prism 8 are (X8, Y8), then point (X4, Y4) coincides with point (X8, Y8); if the center position coordinates of the third coupling unit 5 are (X5, Y5) and the center position coordinates of the third right-angle turning prism 9 are (X9, Y9), then point (X5, Y5) coincides with point (X9, Y9).

[0040] In one embodiment, the diameters of the first coupling unit 3, the second coupling unit 4, and the third coupling unit 5 satisfy D11 = D12 = D13 = 2mm to 6mm, where D11 is the diameter of the first coupling unit 3, D12 is the diameter of the second coupling unit 4, and D13 is the diameter of the third coupling unit 5. The distance between the center of the first coupling unit 3 and the center of the second coupling unit 4 on the straight line, and the distance between the center of the first coupling unit 3 and the center of the third coupling unit 5 on the straight line are both d, and satisfy D11 / 2 ≤ d ≤ D11 / 2 + 1. The straight line of the center of each coupling unit is perpendicular to the waveguide plate 6.

[0041] It should be noted that in this embodiment, the center-to-center distance between two adjacent coupling units along the X-axis is d.

[0042] In one embodiment, the center distance L between the first coupling unit 10 and the second coupling unit 11 satisfies: 58mm≤L≤70mm.

[0043] It should be noted that in this embodiment, the center-to-center distance L is the distance along the X-axis.

[0044] In one embodiment, the refractive index n of the beam splitter 7, the second right-angle bend prism 8, and the third right-angle bend prism 9 is 1.5 to 2.0.

[0045] It should be noted that one right-angle facet of each of the second right-angle turning prism 8 and the third right-angle turning prism 9 is glued to the left and right sides of the beam splitter prism 7, for example, by using a refractive index matching liquid.

[0046] In one embodiment, when the first coupling unit 3, the second coupling unit 4, and the third coupling unit 5 are located on the same side of the waveguide plate 6, the first coupling unit 3 is a rectangular grating, the second coupling unit 4 and the third coupling unit 5 are blazed gratings, and the surface of the blazed gratings is coated with a metal film layer.

[0047] It should be noted that, as Figure 2-3 As shown, each coupling unit is located on the upper side of waveguide plate 6. The metal film layer can be Al or Ag to improve the diffraction efficiency of R+1 and R-1. The T0 diffraction order light generated by the first coupling unit 3 is illustrated using incident rays a and b as examples:

[0048] After the incident ray a enters the beam splitter 7, it passes through the first surface S01 of the beam splitter 7 and, under the action of the semi-transparent and semi-reflective film layer on the surface, part of the incident ray a is converted into reflected ray a1. It reaches the inclined surface S21 of the third right-angle turning prism 9 and, under the action of the high-reflection film or metal film on the inclined surface, ray a1 is reflected into the waveguide plate 6 and interacts with the third coupling unit 5, generating an R-1 diffraction order (with the same direction as the T-1 diffraction order). It then undergoes total internal reflection within the waveguide plate 6 along the -X axis; the other part of the incident ray a ( (The energy of the two parts of the incident ray a is equal) When it passes through the first surface S01, it is converted into a transmitted ray a2, which reaches the third surface S03 of the beam splitter prism 7. Under the action of the high-reflection film or metal film on this surface, the ray a2 is reflected to the inclined surface S11 of the second right-angle turning prism 8. Under the action of the high-reflection film or metal film on this inclined surface, the ray a2 is reflected into the waveguide plate 6 and interacts with the second coupling unit 4, generating the R+1 diffraction order (the direction is the same as the T+1 diffraction order). It is transmitted by total internal reflection along the +X axis in the waveguide plate 6.

[0049] After the incident light ray b enters the beam splitter 7, it passes through the second surface S02 of the beam splitter 7 and, under the action of the semi-transparent and semi-reflective film layer on this surface, part of the incident light ray b is converted into reflected light ray b1. It reaches the inclined surface S11 of the second right-angle turning prism 8 and, under the action of the high-reflection film or metal film on this inclined surface, light ray b1 is reflected into the waveguide plate 6 and interacts with the third coupling unit 5, generating an R+1 diffraction order (with the same direction as the T+1 diffraction order). It then undergoes total internal reflection within the waveguide plate 6 along the +X axis; the other part of the incident light ray b (… (The energy of the two parts of the incident ray b is equal) When it passes through the second surface S02, it is converted into transmitted ray b2, which reaches the fourth surface S04 of the beam splitter prism 7. Under the action of the high-reflection film or metal film on this surface, the ray b2 is reflected to the inclined surface S21 of the third right-angle turning prism 9. Under the action of the high-reflection film or metal film on this inclined surface, the ray b2 is reflected into the waveguide plate 6 and interacts with the second coupling unit 4, generating the R-1 diffraction order (the direction is the same as the T-1 diffraction order). It is transmitted by total internal reflection along the -X axis in the waveguide plate 6.

[0050] In another embodiment, when the second coupling unit 4 and the third coupling unit 5 are located on opposite sides of the waveguide plate 6 relative to the first coupling unit 3, the first coupling unit 3 is a rectangular grating, the second coupling unit 4 and the third coupling unit 5 are tilted gratings, and the surface of the tilted gratings is coated with a high-refractive-index layer.

[0051] It should be noted that, as Figure 4-5 As shown, the second coupling unit 4 and the third coupling unit 5 are disposed on the lower side of the waveguide plate 6, that is, the second coupling unit 4 is located between the waveguide plate 6 and the second right-angle bend prism 8, and the third coupling unit 5 is located between the waveguide plate 6 and the third right-angle bend prism 9. The high-refractive-index layer can be TiO2, Ta2O5, or ZrO2, etc., to improve the diffraction efficiency of the T+1 and T-1 diffraction orders. The T0 diffraction order light generated by the first coupling unit 3 is illustrated using incident ray a and incident ray b as examples:

[0052] After the incident ray a enters the beam splitter 7, it passes through the first surface S01 of the beam splitter 7 and, under the action of the semi-transparent and semi-reflective film layer on the surface, part of the incident ray a is converted into reflected ray a1. It then reaches the inclined surface S21 of the third right-angle turning prism 9 and, under the action of the high-reflection film or metal film on the inclined surface, ray a1 is reflected through the third coupling unit 5. Under the action of the third coupling unit 5, it generates an R-1 diffraction order (with the same direction as the T-1 diffraction order) and undergoes total internal reflection propagation along the -X axis within the waveguide plate 6; the other... When part of the incident light ray a passes through the first surface S01, it is converted into transmitted light ray a2, which reaches the third surface S03 of the beam splitter prism 7. Under the action of the high-reflection film or metal film on this surface, the light ray a2 is reflected to the inclined surface S11 of the second right-angle turning prism 8. Under the action of the high-reflection film or metal film on this inclined surface, the light ray a2 is reflected through the second coupling unit 4. Under the action of the second coupling unit 4, the R+1 diffraction order (with the same direction as the T+1 diffraction order) is generated and transmitted by total internal reflection along the +X axis in the waveguide plate 6.

[0053] After the incident light ray b enters the beam splitter 7, it passes through the second surface S02 of the beam splitter 7. Under the action of the semi-transparent and semi-reflective film layer on this surface, part of the incident light ray b is converted into reflected light ray b1, which reaches the inclined surface S11 of the second right-angle turning prism 8. Under the action of the high-reflection film or metal film on this inclined surface, light ray b1 is reflected and, under the action of the third coupling unit 5, generates the R+1 diffraction order (with the same direction as the T+1 diffraction order). It then undergoes total internal reflection transmission along the +X axis in the waveguide plate 6; the other part... When the transmitted light ray b passes through the second surface S02, it is converted into a transmitted light ray b2, which reaches the fourth surface S04 of the beam splitter 7. Under the action of the high-reflection film or metal film on this surface, the light ray b2 is reflected to the inclined surface S21 of the third right-angle turning prism 9. Under the action of the high-reflection film or metal film on this inclined surface, the light ray b2 is reflected through the second coupling unit 4. Under the action of the second coupling unit 4, the R-1 diffraction order (with the same direction as the T-1 diffraction order) is generated and transmitted by total internal reflection along the -X axis in the waveguide plate 6.

[0054] This zero-order multiplexed single-optical-mechanism binocular display device employs the cooperation of a beam-splitting prism, various right-angle turning prisms, various coupling units, and a waveguide plate. This allows the T0 diffraction order light generated by the first coupling unit to be split into two parts of equal energy, which then enter the second and third right-angle turning prisms respectively. Under the action of the second and third coupling units, T+1 and T-1 diffraction order light, or R+1 and R-1 diffraction order light, are generated and transmitted through total internal reflection within the waveguide plate. After being coupled out by the coupling units, the light enters the left and right eyes, achieving effective utilization of the T0 diffraction order light generated by the first coupling unit. This improves the utilization rate of the micro-optical-mechanism and increases the brightness entering the eyes.

[0055] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above 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.

[0056] The embodiments described above are merely specific and detailed examples of the embodiments described in this application, and should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the scope of protection of this patent application should be determined by the appended claims.

Claims

1. A zero-order multiplexed single-optical-engine binocular display device, characterized in that: The zero-level multiplexed single-optical-mechanical binocular display device includes a micro-optical engine (1), a first right-angled bend prism (2), a first coupling unit (3), a second coupling unit (4), a third coupling unit (5), a waveguide plate (6), a beam splitter (7), a second right-angled bend prism (8) and a third right-angled bend prism (9), a first output unit (10) and a second output unit (11), wherein: The micro-optical engine (1) and the first coupling unit (3) are respectively located on one side of the two right-angled surfaces of the first right-angled turning prism (2). The first coupling unit (3) is set on the waveguide plate (6), and the first coupling unit (3), the waveguide plate (6), and the beam splitter (7) are arranged in sequence. The second coupling unit (4) and the third coupling unit (5) are both set on one side of the waveguide plate (6) and are symmetrically distributed relative to the first coupling unit (3). They are located on the same side or opposite side of the waveguide plate (6) relative to the first coupling unit (3). The first diagonal of the beam splitter (7) A semi-transparent and semi-reflective coating layer and a high-reflective coating layer are successively deposited on the first inclined surface near the waveguide plate (6) and the fourth inclined surface away from the waveguide plate (6) on the second diagonal of the beam splitter (7). A semi-transparent and semi-reflective coating layer and a high-reflective coating layer are successively deposited on the second inclined surface near the waveguide plate (6) and the third inclined surface away from the waveguide plate (6) on the second diagonal of the beam splitter (7). The second right-angle turning prism (8) and the third right-angle turning prism (9) are located on both sides of the beam splitter (7). The first coupling unit (10) and the second coupling unit (11) are respectively set on the waveguide plate (6) and close to the side where the human eye is located. The light emitted from the micro-optical engine (1) is reflected by the inclined surface of the first right-angle turning prism (2) and enters the first coupling unit (3). The first coupling unit (3) generates three diffraction orders: T0, T+1, and T-1. The light of the T+1 and T-1 diffraction orders enters the waveguide plate (6) and is transmitted by total internal reflection in the waveguide plate (6). The light of the T0 diffraction order passes through the waveguide plate (6) and enters the beam splitter (7). It is reflected sequentially by the first and second diagonals of the beam splitter (7) into the second right-angle turning prism (8) and the second right-angle turning prism (9). The three right-angle turning prisms (9) are reflected by the inclined surfaces of the second right-angle turning prism (8) and the third right-angle turning prism (9), respectively, and under the action of the second coupling unit (4) and the third coupling unit (5), the light of the T+1 and T-1 diffraction order or the light of the R+1 and R-1 diffraction order is transmitted by total internal reflection in the waveguide plate (6). Finally, the light of the T+1 and T-1 diffraction order or the light of the T+1, T-1, R+1 and R-1 diffraction order is coupled out to the human eye through the first coupling unit (10) and the second coupling unit (11).

2. The zero-level multiplexing single-optical-mechanical binocular display device as described in claim 1, characterized in that: Each of the coupling units is an embossed grating or a volume Bragg grating, and the period of each of the coupling units is 300nm to 500nm.

3. The zero-level multiplexing single-optical-mechanical binocular display device as described in claim 1, characterized in that: When the first coupling unit (3), the second coupling unit (4) and the third coupling unit (5) are located on the same side of the waveguide plate (6), the first coupling unit (3) is a rectangular grating, the second coupling unit (4) and the third coupling unit (5) are blazed gratings, and the surface of the blazed grating is coated with a metal film layer.

4. The zero-level multiplexing single-optical-mechanical binocular display device as described in claim 1, characterized in that: When the second coupling unit (4) and the third coupling unit (5) are located on opposite sides of the waveguide plate (6) relative to the first coupling unit (3), the first coupling unit (3) is a rectangular grating, the second coupling unit (4) and the third coupling unit (5) are tilted gratings, and the surface of the tilted grating is coated with a high-refractive-index layer.

5. The zero-level multiplexing single-optical-mechanical binocular display device as described in claim 1, characterized in that: The beam splitter (7) is an X-CUBE beam combining prism, and its surface is coated with an anti-reflection film.

6. The zero-level multiplexing single-optical-mechanical binocular display device as described in claim 1, characterized in that: Each of the right-angle turning prisms has a high-reflection coating or a metal coating on its inclined surface, and both right-angle surfaces are coated with an anti-reflection coating.

7. The zero-level multiplexing single-optical-mechanical binocular display device as described in claim 1, characterized in that: The center of the first coupling unit (3) and the center of the beam splitter (7) form a first straight line, the center of the second coupling unit (4) and the center of the second right-angle turning prism (8) form a second straight line, and the center of the third coupling unit (5) and the center of the third right-angle turning prism (9) form a third straight line. The first, second and third straight lines are all perpendicular to the waveguide plate (6).

8. The zero-level multiplexing single-optical-mechanical binocular display device as described in claim 1, characterized in that: The diameters of the first coupling unit (3), the second coupling unit (4), and the third coupling unit (5) satisfy D11 = D12 = D13 = 2mm ~ 6mm, where D11 is the diameter of the first coupling unit (3), D12 is the diameter of the second coupling unit (4), and D13 is the diameter of the third coupling unit (5). The distance between the center line of the first coupling unit (3) and the center line of the second coupling unit (4), and the distance between the center line of the first coupling unit (3) and the center line of the third coupling unit (5) are both d, and satisfy (D11 / 2) ≤ d ≤ (D11 / 2) + 1. The center line of each coupling unit is perpendicular to the waveguide plate (6).

9. The zero-level multiplexing single-optical-mechanical binocular display device as described in claim 1, characterized in that: The center distance L between the first coupling unit (10) and the second coupling unit (11) satisfies: 58mm≤L≤70mm.

10. The zero-level multiplexing single-optical-mechanical binocular display device as described in claim 1, characterized in that: The refractive index n of the beam splitter (7), the second right-angle bend prism (8), and the third right-angle bend prism (9) is 1.5 to 2.0.

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