Polarization beam splitting module, optical assembly and optical equipment

Abstract

The embodiment of the utility model discloses a polarization beam splitting module, an optical assembly and optical equipment, relates to the technical field of polarization beam splitting, and solves the problem that the imaging quality of an optical module is affected by great wavefront aberration brought by an existing metal wire grating polarizer. The polarization beam splitting module comprises a first lens, a second lens and at least one metal wire grating group. Wherein the first lens and the second lens are oppositely arranged. The at least one metal wire grating group is stacked between the first lens and the second lens. And one metal wire grating group comprises two same metal wire grating structures. The metal wire grid structure comprises a substrate and a metal wire grid layer, and the metal wire grid layer is arranged on the substrate. And the substrates of the two metal wire grating structures in the same metal wire grating group are arranged close to each other. The polarization beam splitting module is applied to an optical imaging system, wavefront aberration cannot occur during imaging, wavefront distortion is low, and the imaging quality of the optical imaging system is improved.

Description

Technical Field

[0001] The present application relates to the field of polarization beam splitting technology, and in particular to a polarization beam splitting module, an optical component and an optical device. Background Art

[0002] In optical communication systems and optical imaging systems, polarization beam splitters play an important role. Polarization beam splitters are optical components that separate the horizontal polarization and vertical polarization of a beam of light and convert natural light into polarized light.

[0003] With the development and improvement of nano-processing technology, the metal wire grid polarization beam splitting technology with nanostructure has been further developed. The metal wire grid polarizer has a nanoscale sub-wavelength grating structure, which can realize the regulation of light field characteristics such as reflection, transmission, spectrum, and polarization. In addition, the metal wire grid polarizer has the advantages of small size, integration, flexible design, and sensitivity to polarized light, and can be applied to various optical scenarios. In particular, the metal wire grid solution has obvious advantages in scenarios requiring wide band, large field of view, and high polarization extinction ratio. However, in optical imaging application scenarios, the nanoscale sub-wavelength grating structure will bring about great wavefront aberrations. In turn, it affects the imaging quality of the optical imaging system. Utility Model Content

[0004] The present application provides a polarization beam splitting module, an optical component and an optical device, which solve the problem that the existing metal wire grid polarizer will bring about a huge wavefront aberration and affect the imaging quality of the optical module.

[0005] In order to achieve the above objectives, this application adopts the following technical solutions:

[0006] In the first aspect, an embodiment of the present application provides a polarization beam splitting module. The polarization beam splitting module includes a first lens, a second lens, and one or more metal wire grid groups. The first lens is arranged opposite to the second lens. All metal wire grid groups are stacked between the first lens and the second lens. A metal wire grid group includes two identical metal wire grid structures, the metal wire grid structure includes a substrate and a metal wire grid layer, and the metal wire grid layer is arranged on the substrate. The substrates of the two metal wire grid structures in the same metal wire grid group are arranged close to each other.

[0007] Taking the polarization beam splitting module including a metal wire grid group as an example, the metal wire grid group includes a first metal wire grid structure and a second metal wire grid structure, the base of the first metal wire grid structure and the base of the second metal wire grid structure are arranged close to each other, the metal wire grid layer in the first metal wire grid structure faces the first lens, and the metal wire grid layer in the second metal wire grid structure faces the second lens. That is, the first metal wire grid structure and the second metal wire grid structure are arranged "back to back".

[0008] When the polarization beam splitting module of the embodiment of the present application is applied to an optical imaging system, the light beam can be emitted to the first lens. For example, the optical imaging system includes a first reflecting element and a second reflecting element, the first reflecting element is arranged on the reflected light path of the first lens, and the second reflecting element is arranged on the transmitted light path of the second lens. When the light beam passes through the first lens and is incident on the metal wire grid layer of the first metal wire grid structure, the light beam is split by the metal wire grid layer into two polarized light beams, such as S polarized light and P polarized light. After the S polarized light is reflected, it is incident on the first reflecting element through the first lens. After the S polarized light is reflected by the first reflecting element again, it is transmitted through the first lens, the first metal wire grid structure, the second metal wire grid structure and the second lens in sequence and then emitted. The P polarized light is transmitted through the base of the first metal wire grid structure and the second lens to the second reflecting element in sequence, and is reflected by the second reflecting element. Afterwards, the P polarized light is transmitted through the second lens and is reflected by the metal wire grid layer of the second metal wire grid structure to the second lens. Finally, the P polarized light also emerges from the second lens. The optical path of the S polarized light and the optical path of the P polarized light both need to pass through the same first metal wire grid structure and the second metal wire grid structure. Since the first metal wire grid structure and the second metal wire grid structure are arranged "back to back", even if S-polarized light or P-polarized light generates aberration when passing through the metal wire grid layer of one metal wire grid structure, the aberration can be corrected when passing through the metal wire grid layer of another metal wire grid structure arranged in the opposite direction, so that no wavefront aberration will occur during imaging. The wavefront distortion of the optical imaging system is low, thereby improving the imaging quality of the optical imaging system.

[0009] Among them, the metal wire grid layer includes a plurality of metal wire grids arranged at intervals. The above-mentioned identical metal wire grid structure means that the structural parameters of the two metal wire grid structures in the same group are the same and the shapes of the two metal wire grid structures are also the same. The above-mentioned structural parameters include the period of the metal wire grid, the line width of the metal wire grid, the groove depth of the metal wire grid, the length of the metal wire grid, the length of the substrate, the width of the substrate and the thickness of the substrate. The same shape means that the shape of the substrate, the shape of the metal wire grid, the extension direction of the metal wire grid and the distribution direction of multiple metal wire grids in the two metal wire grid structures in the same group are the same.

[0010] Furthermore, the first lens and a metal wire grid layer of an adjacent metal wire grid structure, the second lens and a metal wire grid layer of an adjacent metal wire grid structure, and the substrates of two metal wire grid structures in the metal wire grid group may be spaced apart or connected in a variety of ways.

[0011] In some embodiments of the present application, the first lens is connected to the metal wire grid layer of an adjacent metal wire grid structure by gluing. The bases of two metal wire grid structures in the metal wire grid group, and the second lens and the metal wire grid layer of an adjacent metal wire grid structure are also connected by gluing. The connection methods between the first lens and the metal wire grid layer of an adjacent metal wire grid structure, and between the second lens and the metal wire grid layer of an adjacent metal wire grid structure are both relatively simple.

[0012] Alternatively, in some other embodiments of the present application, the first lens is connected to the metal wire grid layer of an adjacent metal wire grid structure by using an optical adhesive process. That is, the first lens is connected to the metal wire grid layer of an adjacent metal wire grid structure by van der Waals force. The substrates of the two metal wire grid structures in the metal wire grid group, as well as the second lens and the metal wire grid layer of an adjacent metal wire grid structure, are also connected by using an optical adhesive process. That is, the second lens is connected to the metal wire grid layer of an adjacent metal wire grid structure by van der Waals force.

[0013] Alternatively, the first lens and a metal wire grid layer of an adjacent metal wire grid structure, the bases of two metal wire grid structures in the metal wire grid group, and the second lens and a metal wire grid layer of an adjacent metal wire grid structure may be connected by a mechanical fixing structure such as a fixing frame.

[0014] It should be noted that the connection method between the first lens and the metal wire grid layer of an adjacent metal wire grid structure, the base of the two metal wire grid structures in the metal wire grid group, and the second lens and the metal wire grid layer of an adjacent metal wire grid structure can be the same or different, and this application does not impose any restrictions on this. For a polarization beam splitting module including multiple metal wire grid groups, two adjacent metal wire grid groups can also be connected by gluing, optical glue process or mechanical fixing structure.

[0015] The first lens may be in various shapes. For example, in some embodiments of the present application, the first lens is an optical prism. In other embodiments of the present application, the first lens is an optical flat plate. Thus, the polarization splitting requirements of different application scenarios are met.

[0016] The second lens may also be in various shapes. For example, in some embodiments of the present application, the second lens is an optical prism. In other embodiments of the present application, the second lens is an optical flat plate. Thus, the polarization splitting requirements of different application scenarios are met.

[0017] For example, the first lens and the second lens are both 45° prisms. Therefore, the first lens and the second lens each have a 45° inclined surface. The 45° inclined surface of the first lens is arranged opposite to the 45° inclined surface of the second lens. A plurality of metal wire grid groups are stacked and arranged between the two 45° inclined surfaces.

[0018] In the second aspect, the embodiment of the present application also includes an optical component, including a first reflective element, a second reflective element and the polarization beam splitting module described in the above embodiment. The first reflective element is located on the reflected light path of the first lens in the polarization beam splitting module, and the second reflective element is located on the transmitted light path of the second lens in the polarization beam splitting module. Alternatively, the first reflective element is located on the reflected light path of the second lens in the polarization beam splitting module, and the second reflective element is located on the transmitted light path of the first lens in the polarization beam splitting module. Since the polarization beam splitting module in the optical component of the embodiment of the present application has the same structure as the polarization beam splitting module described in the above embodiment, both can solve the same technical problems and obtain the same technical effects, which will not be repeated here.

[0019] In some embodiments of the present application, the above-mentioned optical component also includes a wave plate. For the case where the first reflective element is located on the reflected light path of the first lens in the polarization beam splitting module, and the second reflective element is located on the transmitted light path of the second lens in the polarization beam splitting module, the wave plate is arranged on the light path between the first reflective element and the first lens, or on the light path between the second reflective element and the second lens. For the case where the first reflective element is located on the reflected light path of the second lens in the polarization beam splitting module, and the second reflective element is located on the transmitted light path of the first lens in the polarization beam splitting module, the wave plate is arranged on the light path between the first reflective element and the second lens, or on the light path between the second reflective element and the first lens. The wave plate can change the polarization direction of the light beam, and can be used as a beam splitter with a variable ratio when used in conjunction with the polarization beam splitting module.

[0020] Furthermore, in some examples of the present application, the wave plate and the first reflective element are an integrated structure, or the wave plate and the second reflective element are an integrated structure. For example, taking the wave plate and the first reflective element as an integrated structure as an example, the first reflective element is a reflective film, and the reflective film is coated on one side surface of the wave plate. Thus, the structure of the optical component is more compact, which is conducive to the miniaturization design of the applied optical device.

[0021] In a third aspect, the embodiment of the present application further includes an optical device, including a housing and the optical assembly described in the above embodiment. The optical assembly is arranged in the housing. Since the optical assembly in the optical device of the embodiment of the present application has the same structure as the optical assembly described in the above embodiment, both can solve the same technical problems and obtain the same technical effects, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to illustrate the technical solution of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be described below.

[0023] Figure 1 This is a schematic diagram of the structure of a projector, in which the optical device in the embodiment of the present application is a projector;

[0024] Figure 2 This is a schematic diagram of the side structure of the polarization beam splitting module according to an embodiment of the present application;

[0025] Figure 3 This is a schematic diagram of the side structure of a polarization beam splitting module with two metal wire grid structures according to an embodiment of the present application;

[0026] Figure 4 This is an exploded schematic diagram of a polarization beam splitting module according to an embodiment of the present application;

[0027] Figure 5 A schematic diagram of the three-dimensional structure of a metal wire grid structure in a polarization beam splitting module according to an embodiment of the present application;

[0028] Figure 6 A schematic diagram of the optical paths of the polarization beam splitting module, the first reflective element, and the second reflective element according to an embodiment of the present application;

[0029] Figure 7 This is a schematic diagram of the side structure of a polarization beam splitting module in which the first lens and the second lens are both optical flat plates according to an embodiment of the present application;

[0030] Figure 8 This is an exploded schematic diagram of a polarization beam splitting module in which both the first lens and the second lens are optical flat plates according to an embodiment of the present application;

[0031] Fig. 9 A schematic diagram of the optical path of the polarization beam splitting module, the wave plate, the first reflective element and the second reflective element in an embodiment of the present application;

[0032] Fig.10 It is a schematic diagram of the optical path of the polarization beam splitting module, the wave plate with an integrated structure, and the first reflecting element and the second reflecting element according to an embodiment of the present application.

[0033] Figure Number:

[0034] 1000-projector; 100-housing; 200-polarization beam splitting module; 1-first lens; 2-second lens; 3-metal wire grid group; 31-metal wire grid structure; 31a-first metal wire grid structure; 31b-second metal wire grid structure; 311-substrate; 312-metal wire grid layer; 3121-metal wire grid; 300-first reflecting element; 400-fourth reflecting element; 500-wave plate. DETAILED DESCRIPTION

[0035] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings.

[0036] In the following, the terms "first", "second", etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0037] In addition, in the present application, directional terms such as "up", "down", "left", "right", "horizontal" and "vertical" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they may change accordingly according to the changes in the orientation of the components in the drawings.

[0038] In this application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can refer to the connection of mechanical structure or physical structure. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be directly connected or indirectly connected through an intermediate medium. It can also be understood as the physical contact and electrical conduction of components, and it can also be understood as the form in which different components in the circuit structure are connected through physical lines such as PCB copper foil or wires that can transmit electrical signals.

[0039] The present application provides an optical device, which may include a mobile phone, a camera, a projector, augmented reality (AR) glasses, an AR helmet, virtual reality (VR) glasses or a VR helmet, etc. The embodiments of the present application do not impose any special restrictions on the specific form of the above optical devices.

[0040] Taking the optical device as a projector as an example, refer to Figure 1 The projector 1000 includes a housing 100, an optical component, a control circuit, etc. A mounting cavity is formed in the housing 100. The optical component is arranged in the mounting cavity of the housing 100. The optical component includes a light source, a projection film, various optical lenses, etc. Various optical lenses are important imaging elements of the projector 1000. Various optical lenses include a condenser, a reflector, a projection film, and a polarization beam splitter, etc.

[0041] Polarization beam splitters are mainly divided into multilayer thin film polarization beam splitters, dichroic polarization beam splitters and birefringent crystal polarization beam splitters. However, with the development and improvement of nano-processing technology, metal wire grid polarizers have also appeared. If the above-mentioned polarization beam splitter adopts a metal wire grid polarizer, the metal wire grid polarizer has the advantages of small size, integration, flexible design, and sensitivity to polarized light. However, the metal wire grid polarizer has a nanoscale sub-wavelength grating structure. The nanoscale sub-wavelength grating structure will bring about a huge wavefront aberration when directly emitting a light beam. In turn, it affects the imaging quality of the projector 1000.

[0042] Therefore, the present application provides a polarization beam splitting module 200 with an improved structure. Figure 2 The polarization beam splitting module 200 includes a first lens 1, a second lens 2 and a metal wire grid group 3. The first lens 1 and the second lens 2 are arranged opposite to each other. The metal wire grid group 3 in the polarization beam splitting module 200 can be one, or two or more, and the present application does not impose any restrictions on this. All metal wire grid groups 3 are stacked between the first lens 1 and the second lens 2. The metal wire grid group 3 can be spaced apart from the first lens 1 and the second lens 2, or can be connected to the first lens 1 and the second lens 2.

[0043] For the sake of convenience, the following description is made by taking the metal wire grid group 3 in the polarization beam splitting module 200 as an example. Figure 3 and Figure 4 As shown, the metal wire grid group 3 includes two metal wire grid structures 31, which are a first metal wire grid structure 31a and a second metal wire grid structure 31b. The first metal wire grid structure 31a faces the first lens 1, and the second metal wire grid structure 31b faces the second lens 2.

[0044] like Figure 5 As shown, the metal wire grid structure 31 includes a substrate 311 and a metal wire grid layer 312, and the metal wire grid layer 312 includes a plurality of metal wire grids 3121 arranged at intervals. The metal wire grid layer 312 is arranged on the substrate 311. Moreover, the substrates 311 of the two metal wire grid structures 31 in the same metal wire grid group 3 are arranged close to each other. Therefore, the metal wire grid layer 312 in the first metal wire grid structure 31a faces the first lens 1, and the metal wire grid layer 312 in the second metal wire grid structure 31b faces the second lens 2. That is, the first metal wire grid structure 31a and the second metal wire grid structure 31b are arranged "back to back".

[0045] Furthermore, the first metal wire grid structure 31a is the same as the second metal wire grid structure 31b. The same includes that the structural parameters of the first metal wire grid structure 31a are the same as those of the second metal wire grid structure 31b, and the shape of the first metal wire grid structure 31a is the same as that of the second metal wire grid structure 31b. The above structural parameters may include the period, line width, groove depth and length of the metal wire grid 3121, the length, width and thickness of the substrate 311, etc. The same shape means that the shape of the substrate 311, the shape of the metal wire grid 3121, the extension direction of the metal wire grid 3121, the distribution direction of the multiple metal wire grids 3121 in the first metal wire grid structure 31a are the same as the shape of the substrate 311, the shape of the metal wire grid 3121, the extension direction of the metal wire grid 3121, the distribution direction of the multiple metal wire grids 3121, etc. in the second metal wire grid structure 31b.

[0046] When the polarization beam splitting module 200 is applied to the projector 1000, Figure 6 As shown, the optical component also includes a first reflective element 300 and a second reflective element 400. The first reflective element 300 and the second reflective element 400 can be a reflector or a reflective film, and the present application does not limit this. If the light source beam can be emitted to the first lens 1 first, the first reflective element 300 is located on the reflected light path of the first lens 1 in the polarization beam splitting module 200, and the second reflective element 400 is located on the transmitted light path of the second lens 2 in the polarization beam splitting module 200. If the light source beam can be emitted to the second lens 2 first, the first reflective element 300 is located on the reflected light path of the second lens 2 in the polarization beam splitting module 200, and the second reflective element 400 is located on the transmitted light path of the first lens 1 in the polarization beam splitting module 200.

[0047] In the following, it is taken as an example that the light source beam can be emitted to the first lens 1 first. When the light source beam is incident on the metal wire grid layer 312 of the first metal wire grid structure 31a through the first lens 1, the light beam is split into two polarized lights, such as S polarized light and P polarized light, by the metal wire grid layer 312. The S polarized light is reflected and incident on the first reflective element 300 through the first lens 1. After the S polarized light is reflected by the first reflective element 300, it is transmitted through the first lens 1, the metal wire grid layer 312 and the substrate 311 of the first metal wire grid structure 31a, the substrate 311 and the metal wire grid layer 312 of the second metal wire grid structure 31b, and the second lens 2 in sequence before being emitted. The P polarized light is transmitted through the substrate 311 of the first metal wire grid structure 31a to the second lens 2, and then emitted to the second reflective element 400. After the P polarized light is reflected by the second reflective element 400, it is transmitted through the second lens 2 to the second metal wire grid structure 31b. The P-polarized light is then reflected by the metal wire grid layer 312 of the second metal wire grid structure 31b, and then emitted after being transmitted through the second lens 2. The optical path of the S-polarized light and the optical path of the P-polarized light both need to pass through the same first metal wire grid structure 31a and second metal wire grid structure 31b. Since the first metal wire grid structure 31a and the second metal wire grid structure 31b are arranged "back to back", even if the S-polarized light or the P-polarized light generates aberration when passing through one metal wire grid structure 31, the aberration can be corrected when passing through another metal wire grid structure 31 arranged in the opposite direction, and no wavefront aberration will occur when the projector 1000 is imaging. The wavefront distortion of the projector 1000 is low, which improves the imaging quality of the projector 1000.

[0048] Furthermore, the first metal wire grid structure 31a and the first lens 1, the second metal wire grid structure 31b and the second lens 2, and the base 311 of the first metal wire grid structure 31a and the base 311 of the second metal wire grid structure 31b can be spaced apart or connected in various ways.

[0049] Several specific embodiments of connecting the first metal wire grid structure 31a and the first lens 1, the second metal wire grid structure 31b and the second lens 2, and the base 311 of the first metal wire grid structure 31a and the base 311 of the second metal wire grid structure 31b are listed below.

[0050] In some embodiments of the present application, the base 311 of the first metal wire grid structure 31a and the base 311 of the second metal wire grid structure 31b are connected by gluing. In addition, the metal wire grid layer 312 of the first metal wire grid structure 31a and the first lens 1 are also connected by gluing. The metal wire grid layer 312 of the second metal wire grid structure 31b is also connected to the second lens 2 by gluing. The connection methods of the base 311 of the first metal wire grid structure 31a and the base 311 of the second metal wire grid structure 31b, the metal wire grid layer 312 of the first metal wire grid structure 31a and the first lens 1, and the metal wire grid layer 312 of the second metal wire grid structure 31b and the second lens 2 are all relatively simple.

[0051] In some other embodiments of the present application, the substrate 311 of the first metal wire grid structure 31a and the substrate 311 of the second metal wire grid structure 31b are connected by optical adhesive technology. That is, the substrate 311 of the first metal wire grid structure 31a and the substrate 311 of the second metal wire grid structure 31b are connected by van der Waals force. In addition, the metal wire grid layer 312 of the first metal wire grid structure 31a and the first lens 1 are also connected by optical adhesive technology. The metal wire grid layer 312 of the second metal wire grid structure 31b is also connected to the second lens 2 by optical adhesive technology. The connection method of the substrate 311 of the first metal wire grid structure 31a and the substrate 311 of the second metal wire grid structure 31b, the metal wire grid layer 312 of the first metal wire grid structure 31a and the first lens 1, and the metal wire grid layer 312 of the second metal wire grid structure 31b and the second lens 2 is also relatively simple.

[0052] In some other embodiments of the present application, the base 311 of the first metal wire grid structure 31a and the base 311 of the second metal wire grid structure 31b, the first metal wire grid structure 31a and the metal wire grid layer 312 of the first lens 1, and the second metal wire grid structure 31b and the metal wire grid layer 312 of the second lens 2 are connected by a mechanical fixing structure. For example, the mechanical fixing structure is a fixing frame, and the fixing frame fixes the first lens 1, the second lens 2, and the metal wire grid group 3 together.

[0053] It should be noted that the connection method between the substrate 311 of the first metal wire grid structure 31a and the substrate 311 of the second metal wire grid structure 31b, the metal wire grid layer 312 of the first metal wire grid structure 31a and the first lens 1, and the metal wire grid layer 312 of the second metal wire grid structure 31b and the second lens 2 can be the same or different, and the present application does not impose any restrictions on this.

[0054] For the polarization beam splitting module 200 including a plurality of metal wire grid groups 3 , two adjacent metal wire grid groups 3 may also be connected by gluing, optical glue or mechanical fixing structure.

[0055] The above is mainly an explanation of the first metal wire grid structure 31a and the second metal wire grid structure 31b. As for the first lens 1 and the second lens 2, a suitable structure can be selected according to application requirements.

[0056] In some embodiments of the present application, the first lens 1 is an optical prism. In other embodiments of the present application, the first lens 1 is an optical flat plate. Thus, the polarization beam splitting requirements of different application scenarios are met.

[0057] Accordingly, the second lens 2 may also adopt a variety of structures. In some embodiments of the present application, for example Figure 5 As shown, the second lens 2 is an optical prism. In other embodiments of the present application, Figure 7 and Figure 8 As shown, the second lens 2 is an optical flat plate, thereby meeting the polarization beam splitting requirements of different application scenarios.

[0058] like Figure 3 and Figure 4 As shown, in some embodiments of the present application, the first lens 1 and the second lens 2 are both 45° prisms. Therefore, the first lens 1 and the second lens 2 each have a 45° bevel. The 45° bevel of the first lens 1 is arranged opposite to the 45° bevel of the second lens 2. The first metal wire grid structure 31a and the second metal wire grid structure 31b are stacked between the 45° bevel of the first lens 1 and the 45° bevel of the second lens 2.

[0059] Furthermore, in some embodiments of the present application, the optical component includes Fig. 9 The wave plate 500 shown can be a 1 / 2 wave plate or a 1 / 4 wave plate, and the present application does not limit this. The wave plate 500 can be used in conjunction with the polarization beam splitting module 200 as a beam splitter with a variable ratio.

[0060] If the first reflecting element 300 is located on the reflected light path of the first lens 1 in the polarization beam splitting module 200, and the second reflecting element 400 is located on the transmitted light path of the second lens 2 in the polarization beam splitting module 200, then the wave plate 500 can be located on the light path between the first reflecting element 300 and the first lens 1, or on the light path between the second reflecting element 400 and the second lens 2.

[0061] If the first reflecting element 300 is located on the reflected light path of the second lens 2 in the polarization beam splitting module 200, and the second reflecting element 400 is located on the transmitted light path of the first lens 1 in the polarization beam splitting module 200, then the wave plate 500 can be located on the light path between the first reflecting element 300 and the second lens 2, or on the light path between the second reflecting element 400 and the first lens 1.

[0062] It should be noted that the wave plate 500 may be spaced apart from the first reflective element 300 or the second reflective element 400 , or may be an integral structure with the first reflective element 300 or the second reflective element 400 .

[0063] In some embodiments of the present application, the wave plate 500 is an integrated structure with the first reflective element 300 or the second reflective element 400. For example, the wave plate 500 is located between the first reflective element 300 and the first lens 1. Fig.10 As shown, the first reflective element 300 is a reflective film, which is coated on one side surface of the wave plate 500. Therefore, the first reflective element 300 and the wave plate 500 are an integrated structure, and the structure of the optical component is more compact, which is conducive to the miniaturization design of the projector.

[0064] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A polarization beam splitting module, characterized in that: include: First lens; a second lens, wherein the first lens and the second lens are arranged opposite to each other; At least one metal wire grid group, wherein the at least one metal wire grid group is stacked between the first lens and the second lens; one of the metal wire grid groups includes two identical metal wire grid structures, wherein the metal wire grid structure includes a substrate and a metal wire grid layer disposed on the substrate; the substrates of the two metal wire grid structures in the same metal wire grid group are disposed close to each other.

2. The polarization beam splitting module according to claim 1, characterized in that: The first lens and the adjacent metal wire grid layer, and the second lens and the adjacent metal wire grid layer are connected by gluing or optical bonding.

3. The polarization beam splitting module according to claim 1 or 2, characterized in that: The first lens is an optical prism or an optical plate.

4. The polarization beam splitting module according to claim 1 or 2, characterized in that: The second lens is an optical prism or an optical plate.

5. The polarization beam splitting module according to claim 1 or 2, characterized in that: The first lens and the second lens are both 45° prisms; the 45° inclined surface of the first lens is arranged opposite to the 45° inclined surface of the second lens.

6. An optical component, characterized in that: include: The polarization beam splitting module according to any one of claims 1 to 5; A first reflecting element and a second reflecting element, wherein the first reflecting element is located on a reflected light path of a first lens in the polarization beam splitting module, and the second reflecting element is located on a transmitted light path of a second lens in the polarization beam splitting module; Alternatively, the first reflecting element is located on the reflected light path of the second lens in the polarization beam splitting module, and the second reflecting element is located on the transmitted light path of the first lens in the polarization beam splitting module.

7. The optical component according to claim 6, characterized in that The optical assembly further comprises: A wave plate, wherein the wave plate is configured as: If the first reflecting element is located on the reflected light path of the first lens in the polarization beam splitting module, and the second reflecting element is located on the transmitted light path of the second lens in the polarization beam splitting module, the wave plate is arranged on the light path between the first reflecting element and the first lens, or on the light path between the second reflecting element and the second lens; If the first reflecting element is located on the reflected light path of the second lens in the polarization beam splitting module, and the second reflecting element is located on the transmitted light path of the first lens in the polarization beam splitting module, the wave plate is arranged on the light path between the first reflecting element and the second lens, or on the light path between the second reflecting element and the first lens.

8. The optical component according to claim 7, characterized in that The wave plate and the first reflecting element or the second reflecting element are an integral structure.

9. An optical device, characterized in that: include: shell; The optical assembly according to any one of claims 6 to 8, wherein the optical assembly is disposed in the housing.

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