Optical machine module and near-to-eye display device

Abstract

The embodiment of the invention discloses an optical machine module and a near-to-eye display device. The ray machine module comprises a display unit, an imaging lens group, a triangular prism, a waveguide sheet and a reflector group; the display unit and the imaging lens group are arranged at the first end of the triangular prism, the incident end of the waveguide sheet is bonded and fixed with the second end of the triangular prism, and the reflector group is bonded and fixed with the third end of the triangular prism or is arranged on one side, deviating from the incident end, of the waveguide sheet; a polarization beam splitting film is arranged between the second end of the triangular prism and the incident end of the waveguide plate, and a quarter-wave plate is arranged on the side, away from the reflecting face, of the reflecting mirror set. According to the optical machine module provided by the embodiment of the invention, a compact optical architecture scheme in which the array waveguide and the LCOS optical machine are matched for use is provided, extremely miniaturization of the module under the LCOS scheme is facilitated, and the size of the optical machine can be reduced to 0.6 cc or below on the premise that the performance of the optical machine is ensured.

Description

Technical Field

[0001] The present invention relates to the field of near-eye display technology, and in particular to an optical machine module and a near-eye display device. Background Art

[0002] In recent years, augmented reality (AR) technology has developed rapidly, and a series of related commercial products have been released. This technology superimposes virtual images on the real world perceived by users, which can create a realistic experience and has great application prospects in security, industry, and medical care. In order to realize the function of augmented reality, researchers have proposed a variety of solutions, such as Birdbath, prism, free-form surface, optical waveguide and other technologies. In the first three solutions, there is often a contradiction between good product form and better display effect, while optical waveguide can effectively solve the above problems, and the solution of optical machine plus optical waveguide is a lightweight and miniaturized AR development solution, which is the most important in the future.

[0003] In the optical waveguide technology solution, an optical engine, i.e., an optical machine, is required as an image generation unit. Generally speaking, optical waveguides can be made thinner and lighter, and their shape is close to the size and shape of eyeglass lenses. Except for the Micro LED solution, which can achieve a volume of about 0.2 cubic centimeters (cc) in small and medium fields of view, the optical machines of other solutions are all above 1cc, especially the optical machines with a field of view (FOV) of more than 50 degrees. As the field of view increases, the volume is 1.5cc or even more than 2cc. Since the resolution and cost of Micro LED are still inferior to those of silicon-based liquid crystal (LCOS), LCOS optical machines are still very important AR optical machine solutions in the short term, but the existing LCOS optical machine modules are relatively large, which affects their promotion and application. Summary of the invention

[0004] An embodiment of the present invention provides an optical-mechanical module and a near-eye display device. The optical-mechanical module proposes a compact optical architecture solution in which an array waveguide is used in conjunction with an LCOS optical machine, which helps to achieve extreme miniaturization of the module under the LCOS solution and can reduce the size of the optical machine to less than 0.6cc while ensuring the performance of the optical machine.

[0005] According to one aspect of the present invention, there is provided an optical machine module, comprising a display unit, an imaging lens group, a triangular prism, a waveguide plate and a reflector group; The display unit and the imaging mirror group are arranged at the first end of the triangular prism, the incident end of the waveguide plate is bonded and fixed to the second end of the triangular prism, the reflector group is bonded and fixed to the third end of the triangular prism or the reflector group is arranged on the side of the waveguide plate away from the incident end, a polarization beam splitter film is arranged between the second end of the triangular prism and the incident end of the waveguide plate, and a quarter wave plate is arranged on the side of the reflector group away from the reflection surface; The display unit emits or reflects an imaging light beam of a first polarization direction, the imaging light beam is incident on the triangular prism after being transmitted through the imaging mirror group, is converted to a second polarization direction after being reflected by the polarization beam splitter film, is transmitted through the quarter wave plate for the first time, is reflected by the reflector group and is transmitted through the quarter wave plate for the second time, is then incident on the waveguide plate after being transmitted through the polarization beam splitter film, is coupled out to the human eye after being fully reflected and transmitted in the waveguide plate; or the display unit emits or reflects an imaging light beam of a second polarization direction, the imaging light beam is incident on the triangular prism after being transmitted through the imaging mirror group, is converted to the first polarization direction after being transmitted through the polarization beam splitter film, is transmitted through the quarter wave plate for the first time, is reflected by the reflector group and is transmitted through the quarter wave plate for the second time, is then reflected by the polarization beam splitter film and is incident on the waveguide plate, is coupled out to the human eye after being fully reflected and transmitted in the waveguide plate; The first polarization direction is perpendicular to the second polarization direction.

[0006] Optionally, the display unit includes a self-luminous display panel, and the display panel emits an imaging light beam in the first polarization direction or the second polarization direction.

[0007] Optionally, it further includes an illumination lens group and an illumination light source disposed on a side of the waveguide sheet away from the incident end, the illumination light source emits an illumination light beam in the first polarization direction, the illumination light beam is sequentially transmitted through the illumination lens group, the waveguide sheet, the polarization beam splitter film, the triangular prism and the imaging lens group and then incident on the display unit; Alternatively, the optical machine module also includes an illumination lens group and an illumination light source arranged at the third end of the triangular prism, and the illumination light source emits an illumination light beam in the second polarization direction. The illumination light beam is sequentially transmitted through the illumination lens group, the triangular prism, reflected by the polarization beam splitting film, the triangular prism, and the imaging lens group before being incident on the display unit.

[0008] Optionally, it further includes a polarizing plate arranged on the light-emitting side of the illumination light source, and the polarizing plate is used to prevent the illumination light beam from directly entering the waveguide.

[0009] Optionally, a compensating prism is further included which is arranged on the side of the waveguide plate away from the incident end, and the refractive index of the triangular prism and the refractive index of the waveguide plate are the same as the refractive index of the compensating prism.

[0010] Optionally, the illumination lens assembly comprises a collimating lens, a fly-eye lens and an integrating lens sequentially arranged along the transmission direction of the illumination light beam; Wherein, the collimating lens and the integrator lens are both positive power lenses, at least one surface of the collimating lens is a convex surface, and at least one surface of the integrator lens is a convex surface.

[0011] Optionally, the focal length f1 of the collimating lens satisfies 1.5 mm≤f1≤4.5 mm, and the focal length f2 of the integrating lens satisfies 8 mm≤f2≤12 mm.

[0012] Optionally, the imaging lens assembly includes a first lens with positive optical power and a second lens with negative optical power, which are arranged in a direction from the triangular prism to the display unit; Wherein, both surfaces of the first lens are convex, and one surface of the second lens is convex and the other surface is concave.

[0013] Optionally, the focal length f3 of the first lens satisfies 3.5mm≤f3≤8.5mm, and the focal length f4 of the second lens satisfies -18mm≤f4≤-9mm; and the combined focal length f of the first lens and the second lens satisfies 5mm≤f≤12mm.

[0014] According to another aspect of the present invention, a near-eye display device is provided, comprising the above-mentioned optical-mechanical module.

[0015] The optical machine module provided by the embodiment of the present invention includes a display unit, an imaging lens group, a triangular prism, a waveguide plate and a reflector group; the display unit and the imaging lens group are arranged at the first end of the triangular prism, the incident end of the waveguide plate is bonded and fixed to the second end of the triangular prism, the reflector group is bonded and fixed to the third end of the triangular prism or the reflector group is arranged on the side of the waveguide plate away from the incident end, a polarization splitting film is arranged between the second end of the triangular prism and the incident end of the waveguide plate, and a quarter wave plate is arranged on the side of the reflector group away from the reflection surface; compared with the prior art using a square polarization splitting prism, the embodiment of the present invention only uses one triangular prism (equivalent to canceling one triangular prism), and one of the prism coupling ports of the waveguide plate is canceled, so that the retained triangular prism can be directly glued to the coupling port of the waveguide plate, thereby reducing the volume of the optical machine module. The optical path process of the optical machine module provided by the embodiment of the present invention is: the display unit emits or reflects an imaging light beam in a first polarization direction, the imaging light beam is transmitted through the imaging mirror group and then incident on a triangular prism, and is converted to a second polarization direction after being reflected by a polarization splitting film, transmitted through a quarter-wave plate for the first time, reflected by a reflector group and transmitted through the quarter-wave plate for the second time, and then is incident on a waveguide after being transmitted through a polarization splitting film, and is coupled out to a human eye after being totally reflected and transmitted in the waveguide; or the display unit emits or reflects an imaging light beam in a second polarization direction, the imaging light beam is transmitted through the imaging mirror group and then incident on a triangular prism, and is converted to a first polarization direction after being transmitted through a polarization splitting film, transmitted through a quarter-wave plate for the first time, reflected by a reflector group and transmitted through the quarter-wave plate for the second time, and then is incident on a waveguide after being reflected through a polarization splitting film, and is coupled out to a human eye after being totally reflected and transmitted in the waveguide; wherein the first polarization direction and the second polarization direction are perpendicular.

[0016] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 It is a structural schematic diagram of an optical machine module in the prior art; Figure 2 A schematic diagram of the structure of an optical-mechanical module provided by an embodiment of the present invention; Figure 3 A schematic diagram of the structure of another optical-mechanical module provided by an embodiment of the present invention; Figure 4 A schematic diagram of the structure of another optical-mechanical module provided by an embodiment of the present invention; Figure 5 A schematic diagram of the structure of another optical-mechanical module provided by an embodiment of the present invention; Figure 6 A schematic diagram of the structure of the polarizers provided by an embodiment of the present invention when they are bonded; Figure 7 A schematic structural diagram of an illumination mirror assembly provided by an embodiment of the present invention; Figure 8 A schematic structural diagram of an imaging lens assembly provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings 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 ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0020] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0021] Figure 1 It is a structural schematic diagram of an optical machine module in the prior art, referring to Figure 1The optical machine module includes a display unit 1 (which can be a LOCS), an imaging lens group 2, a polarization beam splitter prism 3 (PBS), a waveguide plate 4, a reflector group 5, an illumination lens group 6 and a light source 7. The optical path principle is as follows: the light beam of the illumination light path emitted by the light source 7 is reflected by the polarization beam splitter prism 3 to illuminate the display unit 1 of the imaging light path, and then the light reflected by the display unit 1 passes through the polarization beam splitter prism 3 and the reflector group 5 to enter the incident end (coupling port) of the waveguide plate 4; generally speaking, the inclination angle of the coupling port of the waveguide plate 4 is twice the angle of the coupling splitter surface. Such a matched optical machine module requires a square prism block, which is made of two triangular prisms sandwiched with a polarization beam splitter film and glued together. Therefore, the size of the polarization beam splitter prism occupies a large part of the volume of the optical machine module.

[0022] In order to realize the miniaturization of an optical-mechanical module and reduce the volume of the optical-mechanical module, an embodiment of the present invention provides an optical-mechanical module, including a display unit, an imaging lens group, a triangular prism, a waveguide plate and a reflector group; the display unit and the imaging lens group are arranged at the first end of the triangular prism, the incident end of the waveguide plate is bonded and fixed to the second end of the triangular prism, the reflector group is bonded and fixed to the third end of the triangular prism or the reflector group is arranged on the side of the waveguide plate away from the incident end, a polarization beam splitter film is arranged between the second end of the triangular prism and the incident end of the waveguide plate, and a quarter-wave plate is arranged on the side of the reflector group away from the reflection surface; the display unit emits or reflects an imaging light beam in a first polarization direction, the imaging light beam is incident on the triangular prism after being transmitted through the imaging lens group, and passes through the After reflection from the polarization splitter film, the first transmission from the quarter wave plate, reflection from the reflector group and the second transmission from the quarter wave plate, the light is converted to the second polarization direction, and then is incident on the waveguide after transmission through the polarization splitter film, and is coupled out to the human eye after total reflection transmission in the waveguide; or the display unit emits or reflects an imaging light beam in the second polarization direction, and the imaging light beam is incident on the triangular prism after transmission through the imaging mirror group, and is converted to the first polarization direction after transmission through the polarization splitter film, the first transmission from the quarter wave plate, reflection from the reflector group and the second transmission from the quarter wave plate, and then is reflected from the polarization splitter film and is incident on the waveguide, and is coupled out to the human eye after total reflection transmission in the waveguide; wherein the first polarization direction and the second polarization direction are perpendicular.

[0023] Compared with the traditional solution, the optical-mechanical module provided by the embodiment of the present invention eliminates the square solution of the PBS prism, eliminates one of the triangular prisms, and eliminates one of the prism coupling ports of the waveguide plate, thereby greatly reducing the volume of the optical-mechanical module, so that the retained triangular prism can be directly glued to the coupling port of the waveguide plate, and a PBS film is also glued between the waveguide coupling port and the triangular prism.

[0024] The following is an explanation of specific embodiments of the present invention in conjunction with the accompanying drawings, which are exemplary: Figure 2 A schematic diagram of the structure of an optical machine module provided by an embodiment of the present invention, Figure 3A schematic diagram of another optical-mechanical module provided in an embodiment of the present invention, referring to Figure 2 and Figure 3 , the optical machine module provided by the embodiment of the present invention includes a display unit 10, an imaging lens group 20, a triangular prism 30, a waveguide plate 40 and a reflector group 50. The optical machine module can be used in a near-eye display device, and the display unit 10 is used to emit or reflect an imaging light beam, for example, it can be a Micro LED display panel, an organic light-emitting display (OLED) display panel or a LOCS display panel, and can be designed according to actual conditions during specific implementation. The imaging lens group 20 includes at least one imaging lens for converging the imaging light beam, and an anti-reflection film can be provided at one end of the triangular prism 30 close to the imaging lens group 20 and at one end close to the reflector group 50, and a PBS film is provided at one end of the triangular prism 30 close to the waveguide plate. The waveguide plate 40 is an array waveguide, and the incident light is transmitted by total reflection in the array waveguide ( Figure 2 The total reflection process is not shown in the figure), the waveguide plate 40 includes a plurality of parallel semi-transparent and semi-reflective out-coupling splitter surfaces, and the plurality of out-coupling splitter surfaces are used to emit light. Figure 1 ), due to the elimination of a triangular prism and a prism at the coupling port of the waveguide, the inclination angle b of the coupling port of the waveguide and the inclination angle a of the beam splitter no longer satisfy the relationship b=2a like the traditional waveguide. Instead, it is necessary to ensure that the zero field of view light directly coupled from the optical machine to the waveguide should satisfy the vertical coupling out of the lower surface of the waveguide after the light is reflected from the coupling out beam splitter. Specifically, if the angle of the waveguide coupling out beam splitter is a, the angle c between the total reflection light in the zero field of view waveguide and the lower surface of the waveguide is c=90°-2×a; if the PBS triangular prism is an isosceles right triangular prism, then b=90°-c-45° (the acute angle of the triangular prism glued to the waveguide).

[0025] Continue to refer Figure 2 The display unit 10 and the imaging lens group 20 are arranged at the first end of the triangular prism 30, the incident end of the waveguide plate 40 is bonded and fixed to the second end of the triangular prism 30, the reflector group 50 is bonded and fixed to the third end of the triangular prism 30, and a polarization beam splitting film ( Figure 2 ), a quarter wave plate ( Figure 2 not shown). Figure 2The optical path principle of the optical machine module is also schematically shown: the display unit 10 emits or reflects an imaging light beam in a first polarization direction, the imaging light beam is transmitted through the imaging lens group 20 and then incident on the triangular prism 30, is reflected by the polarization splitter film, transmitted through the quarter-wave plate for the first time, reflected by the reflector group 50 and transmitted through the quarter-wave plate for the second time, and then converted into a second polarization direction, and then transmitted through the polarization splitter film and then incident on the waveguide 40, and is coupled out to the human eye 60 after total reflection transmission in the waveguide 40, wherein the first polarization direction is perpendicular to the second polarization direction.

[0026] It can be understood that, since the polarization splitter film can transmit horizontally polarized light (P light) and reflect vertically polarized light (S light), the first polarization direction can be set to vertical polarization and the second polarization direction can be set to horizontal polarization. When the S light passes through a quarter wave plate, it can be converted into circularly polarized light, and when it passes through the quarter wave plate again, it can be converted into P light. Using this principle, the display unit 10 can be set to emit or reflect S light. After passing through the imaging lens group 20 and the triangular prism 30, the S light is incident on the polarization splitter film for reflection, and then is converted into P light after being transmitted through the quarter wave plate, reflected by the reflector group 50 and transmitted through the quarter wave plate. After being transmitted through the polarization splitter film, it is coupled into the waveguide plate 40, and after being transmitted through the waveguide plate 40, it is coupled out to the human eye 60.

[0027] In another embodiment, the position of the reflector assembly 50 can be adjusted, and the display unit 10 only needs to be set to emit or reflect P light. Figure 3 ,and Figure 2 The difference is that the reflector group 50 is arranged on the side of the waveguide 40 away from the incident end, and the display unit 10 emits or reflects an imaging light beam in the second polarization direction. The imaging light beam is transmitted through the imaging mirror group 20 and then incident on the triangular prism 30. After being transmitted through the polarization splitter film, the first transmission through the quarter-wave plate, the reflection of the reflector group 50 and the second transmission through the quarter-wave plate, it is converted into the first polarization direction, and then reflected by the polarization splitter film and then incident on the waveguide 40. After total reflection transmission in the waveguide 40, it is coupled out to the human eye 60.

[0028] In this embodiment, the display unit 10 emits or reflects P light, the P light is transmitted through the imaging lens group 20 and the triangular prism 30, and then is incident on the polarization splitter film for transmission, and then is converted into S light after being transmitted through the quarter wave plate, reflected by the reflector group 50, and transmitted through the quarter wave plate, and then is reflected by the polarization splitter film and coupled into the waveguide plate 40, and then is coupled out to the human eye 60 after being transmitted through the waveguide plate 40.

[0029] Optional, continue to refer to Figure 2 or Figure 3 The display unit 10 includes a self-luminous display panel, which emits an imaging light beam in a first polarization direction or a second polarization direction.

[0030] In specific implementation, the display panel may be a Micro LED display panel, an OLED display panel, or a LOCS display panel provided with a backlight. In specific implementation, it may be designed according to actual conditions, and the embodiment of the present invention is not limited to this.

[0031] In other embodiments, the display unit 10 may include a non-self-luminous display panel, in which case the illumination light path needs to be designed. For example, Figure 4 A structural diagram of another optical-mechanical module provided by an embodiment of the present invention, Figure 5 A schematic diagram of the structure of another optical machine module provided in an embodiment of the present invention, optionally, refer to Figure 4 The optical machine module also includes an illumination lens group 70 and an illumination light source 80 arranged on a side of the waveguide plate 40 away from the incident end. The illumination light source 80 emits an illumination light beam in a first polarization direction. The illumination light beam is sequentially transmitted through the illumination lens group 70, the waveguide plate 40, the polarization beam splitter film, the triangular prism 30 and the imaging lens group 20 and then incident on the display unit 10. A quarter wave plate is also arranged on the light emitting side of the display unit 10. The subsequent optical path process is the same as Figure 2 The same is not described in detail here.

[0032] refer to Figure 5 The optical machine module also includes an illumination lens group 70 and an illumination light source 80 disposed at the third end of the triangular prism 30. The illumination light source 80 emits an illumination light beam in a second polarization direction. The illumination light beam is sequentially transmitted through the illumination lens group 70, the triangular prism 30, reflected by the polarization beam splitter film, the triangular prism 30, and the imaging lens group 20 before being incident on the display unit 10. A quarter wave plate is also disposed on the light emitting side of the display unit 10. The subsequent optical path process is the same as Figure 3 The same is not described in detail here.

[0033] The illumination light source 80 may be a light emitting diode for providing an illumination beam, which is reflected by the display unit 10 to form an imaging beam. In a specific implementation, if the image to be displayed is a monochrome image, the illumination light source 80 may be a monochrome light source, and if the image to be displayed is a color image, the illumination light source 80 may include red, green, and blue light sources.

[0034] Optional, continue to refer to Figure 3~Figure 5 The optical machine module also includes a compensation prism 90 disposed on the side of the waveguide plate 40 away from the incident end, and the refractive index of the triangular prism 30 and the refractive index of the waveguide plate 40 are the same as the refractive index of the compensation prism 90.

[0035] By providing the compensation prism 90, the light reflected by the reflector assembly 50 can be prevented from being Figure 3 ) or illumination beam ( Figure 5) to prevent unnecessary refraction and change the transmission direction, so as to ensure that the light beam is transmitted in the predetermined direction and that the light beam coupled into the waveguide plate 40 by the optical machine meets the total reflection transmission condition.

[0036] In an embodiment in which an illumination light source is provided, optionally, the optical machine module further includes a polarizing plate provided on a light emitting side of the illumination light source, and the polarizing plate is used to prevent the illumination light beam from being directly incident on the waveguide.

[0037] Among them, the polarizer (POL) can modulate the polarization state of the illumination light beam emitted by the illumination light source into a required polarization state. Figure 4 and Figure 5 In the embodiment shown in the figure, since the illumination light beam directly hits the coupling port of the waveguide plate in the forward direction, although theoretically the polarized illumination light beam is transmitted or reflected by the PBS film and will not enter the waveguide, in reality, there is inevitably a production error (raw material error) between the optical axis angle of the PBS film and the angle of the POL, which may cause the final display contrast of the waveguide to be too low (light leakage due to direct illumination light beam). Figure 6 This is a schematic diagram of the structure of the polarizer provided by the embodiment of the present invention when it is attached, refer to Figure 6 The structure includes an optical machine fixed structure 100, an optical machine 200 (PBS is a POL), a polarizer 300 and a power meter 400. During bonding, the polarizer 300 is directly rotated by positioning the bonded PBS film in the optical machine fixed structure 100, so that the power meter 400 can measure the minimum dark field brightness in the light path under the illumination of the actual light source of the optical machine, and mark the rotation angle of the polarizer 300 at this time as the actual optical axis, and then cut and bond the modules according to this actual optical axis angle.

[0038] Figure 7 A schematic diagram of the structure of an illumination mirror assembly provided by an embodiment of the present invention, referring to Figure 7 Optionally, the lighting lens assembly 70 includes a collimating lens 71, a fly-eye lens 72 and an integrating lens 73 which are sequentially arranged along the transmission direction of the lighting beam; wherein the collimating lens 71 and the integrating lens 73 are both positive focal length lenses, at least one surface of the collimating lens 71 is a convex surface, and at least one surface of the integrating lens 73 is a convex surface.

[0039] Among them, the collimating lens 71 is used to collimate the illumination light beam emitted by the illumination light source, the compound eye lens 72 is used for uniform light, and the integral lens 73 further adjusts the beam quality of the illumination light beam. In specific implementation, the collimating lens 71 can also be split into two positive lenses, which can be designed according to actual conditions. Optionally, the focal length f1 of the collimating lens 71 satisfies 1.5mm≤f1≤4.5mm, and the focal length f2 of the integral lens 73 satisfies 8mm≤f2≤12mm. Setting the above parameters can ensure uniform illumination beam quality under the premise of a small size of the optical machine module.

[0040] Figure 8 A schematic diagram of the structure of an imaging lens assembly provided by an embodiment of the present invention, referring to Figure 8 Optionally, the imaging lens group 20 includes a first lens 21 with positive optical focal length and a second lens 22 with negative optical focal length arranged along the direction of the triangular prism pointing to the display unit; wherein both surfaces of the first lens 21 are convex, and one surface of the second lens 22 is convex and the other surface is concave.

[0041] The first lens 21 and the second lens 22 can be glued together or separated, and can be designed according to actual conditions during implementation. Optionally, the focal length f3 of the first lens 21 satisfies 3.5mm≤f3≤8.5mm, and the focal length f4 of the second lens 22 satisfies -18mm≤f4≤-9mm; the combined focal length f of the first lens 21 and the second lens 22 satisfies 5mm≤f≤12mm. Setting the above parameters can improve the imaging beam quality while ensuring a small size of the optical machine module.

[0042] In summary, the embodiment of the present invention reconstructs a new optomechanical architecture by eliminating a triangular prism at the coupling port of the traditional waveguide plate and a triangular prism of the optomechanical PBS, and can make the waveguide optomechanical module extremely compact. For example, in a certain embodiment, a FOV50 degree module of an array waveguide is designed based on a 0.25-inch LCOS panel. According to the above scheme, the actual optomechanical module volume is reduced by 40% compared with the traditional optomechanical module volume. The volume of the traditional scheme is 1cc, and the volume of the embodiment of the present invention is 0.6cc, and the performance remains basically the same.

[0043] An embodiment of the present invention further provides a near-eye display device, comprising any one of the optical-mechanical modules provided in the above embodiments, wherein the near-eye display device may be a virtual reality display device or an augmented reality display device.

[0044] Since the near-eye display device provided by the embodiment of the present invention includes any one of the optical-mechanical modules provided by the above embodiments and has the same or corresponding technical effects as the optical-mechanical modules, it will not be described in detail here.

[0045] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An optical machine module, characterized in that: It includes a display unit, an imaging lens group, a triangular prism, a waveguide sheet and a reflector group; The display unit and the imaging mirror group are arranged at the first end of the triangular prism, the incident end of the waveguide plate is bonded and fixed to the second end of the triangular prism, the reflector group is bonded and fixed to the third end of the triangular prism or the reflector group is arranged on the side of the waveguide plate away from the incident end, a polarization beam splitter film is arranged between the second end of the triangular prism and the incident end of the waveguide plate, and a quarter wave plate is arranged on the side of the reflector group away from the reflection surface; The display unit emits or reflects an imaging light beam of a first polarization direction, the imaging light beam is incident on the triangular prism after being transmitted through the imaging mirror group, is converted to a second polarization direction after being reflected by the polarization beam splitter film, is transmitted through the quarter wave plate for the first time, is reflected by the reflector group and is transmitted through the quarter wave plate for the second time, is then incident on the waveguide plate after being transmitted through the polarization beam splitter film, is coupled out to the human eye after being fully reflected and transmitted in the waveguide plate; or the display unit emits or reflects an imaging light beam of a second polarization direction, the imaging light beam is incident on the triangular prism after being transmitted through the imaging mirror group, is converted to the first polarization direction after being transmitted through the polarization beam splitter film, is transmitted through the quarter wave plate for the first time, is reflected by the reflector group and is transmitted through the quarter wave plate for the second time, is then reflected by the polarization beam splitter film and is incident on the waveguide plate, is coupled out to the human eye after being fully reflected and transmitted in the waveguide plate; Wherein, the first polarization direction is perpendicular to the second polarization direction.

2. The optical machine module according to claim 1, characterized in that: The display unit includes a self-luminous display panel, and the display panel emits an imaging light beam in the first polarization direction or the second polarization direction.

3. The optical machine module according to claim 1, characterized in that: It also includes an illumination lens group and an illumination light source disposed on a side of the waveguide plate away from the incident end, the illumination light source emits an illumination light beam in the first polarization direction, the illumination light beam is sequentially transmitted through the illumination lens group, the waveguide plate, the polarization beam splitter film, the triangular prism and the imaging lens group and then incident on the display unit; Alternatively, the optical machine module also includes an illumination lens group and an illumination light source arranged at the third end of the triangular prism, and the illumination light source emits an illumination light beam in the second polarization direction. The illumination light beam is sequentially transmitted through the illumination lens group, the triangular prism, reflected by the polarization beam splitting film, the triangular prism, and the imaging lens group before being incident on the display unit.

4. The optical machine module according to claim 3, characterized in that: It also includes a polarizing plate arranged on the light-emitting side of the illumination light source, and the polarizing plate is used to prevent the illumination light beam from directly entering the waveguide plate.

5. The optical machine module according to claim 1 or 3, characterized in that: It also includes a compensation prism arranged on the side of the waveguide plate away from the incident end, and the refractive index of the triangular prism and the refractive index of the waveguide plate are the same as the refractive index of the compensation prism.

6. The optical machine module according to claim 3, characterized in that: The illumination lens assembly comprises a collimating lens, a fly-eye lens and an integrating lens which are sequentially arranged along the transmission direction of the illumination light beam; Wherein, the collimating lens and the integrator lens are both positive power lenses, at least one surface of the collimating lens is a convex surface, and at least one surface of the integrator lens is a convex surface.

7. The optical machine module according to claim 6, characterized in that: The focal length f1 of the collimating lens satisfies 1.5 mm≤f1≤4.5 mm, and the focal length f2 of the integrator lens satisfies 8 mm≤f2≤12 mm.

8. The optical machine module according to claim 1, characterized in that: The imaging lens assembly comprises a first lens with positive optical power and a second lens with negative optical power arranged in a direction from the triangular prism to the display unit; Wherein, both surfaces of the first lens are convex, and one surface of the second lens is convex and the other surface is concave.

9. The optical machine module according to claim 8, characterized in that: The focal length f3 of the first lens satisfies 3.5 mm≤f3≤8.5 mm, the focal length f4 of the second lens satisfies -18 mm≤f4≤-9 mm; and the combined focal length f of the first lens and the second lens satisfies 5 mm≤f≤12 mm.

10. A near-eye display device, characterized in that: Comprising the optical machine module described in any one of claims 1 to 9.

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