Optical system and VR display device

Abstract

The utility model provides an optical system and VR display equipment. The optical system comprises a polarizing film material used for converting imaging light into polarized light; the surface of each lens in the at least one lens is a curved surface, and the polarized light is projected to the at least one lens; and the polarization reflection film material is used for polarizing and reflecting the light emitted by the lens.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to an optical system and a VR display device. Background Art

[0002] Virtual Reality (VR) technology is a computer-generated simulated environment that enables users to interact with and immerse themselves in the virtual world. With the development of VR technology, VR devices are becoming increasingly widely used.

[0003] In related technologies, VR devices set up an optical system on the display side of the display screen. After the display light is transmitted and amplified by the optical system, the image is output to the user. Therefore, the image seen by the user is a virtual image magnified by the optical system.

[0004] VR optical systems have primarily evolved through three phases: aspheric lenses, Fresnel lenses, and folded optical paths (often referred to as Pancake solutions). Traditional lenses used in VR primarily utilize aspheric lenses, which are bulky and heavy, leading to a gradual decline in their use. Fresnel lenses, essentially flattened convex lenses, are adopted by most VR solutions on the market due to their compact size and mature manufacturing process. Aspheric and Fresnel lenses utilize perpendicular optical paths, utilizing the principles of light refraction to transmit and amplify display optics. The Pancake solution utilizes a folded optical path, utilizing the principles of light refraction, reflection, and polarization to achieve a shorter optical path. As a result, the Pancake solution offers superior performance in terms of lightweight design, image quality, and diopter adjustment, and is gradually penetrating the VR market. The implementation of the Pancake solution represents a major innovation in the optical system itself, and how to better utilize it to further enhance user comfort and immersion has become a hot topic in industry research. Utility Model Content

[0005] The present application provides an optical system and a display device for further improving user comfort and immersion based on the Pancake solution.

[0006] In a first aspect, an optical system is provided, comprising: a polarizing film material for converting imaging light into polarized light; at least one lens, wherein the surface of each lens of the at least one lens is a curved surface, and polarized light is projected onto the at least one lens; and a polarizing reflective film material for polarizing and reflecting light emitted through the lens.

[0007] In some embodiments, the polarizing reflective film is located on a side of the at least one lens facing away from the polarizing film.

[0008] In some embodiments, the optical system further includes: a supporting plate, and the polarized reflective film material is attached to the surface of the supporting plate.

[0009] In some embodiments, the carrier plate is located on a side of the at least one lens facing away from the polarizing film.

[0010] In some embodiments, the at least one lens includes a plurality of lenses, the carrier plate is located between two lenses, and the two lenses are spaced apart.

[0011] In some embodiments, the at least one lens includes a target lens, one surface of the target lens is a convex surface protruding away from its optical center, and the polarized reflective film is attached to the convex surface of the target lens.

[0012] In some embodiments, at least one lens includes multiple lenses, the target lens is the outermost lens farthest from the polarizing film material among the multiple lenses, one of the surfaces of the target lens is a convex surface facing away from the polarizing film material, and the polarizing reflective film material is adhered to the outer surface of the target lens.

[0013] In some embodiments, the at least one lens includes a plurality of lenses, and two adjacent lenses in the plurality of lenses are connected by a bonding layer.

[0014] In some embodiments, the polarized reflective film includes a quarter wave plate, a reflective polarizer, an absorptive polarizer, and an anti-reflection film that are arranged in sequence and connected by a glue layer.

[0015] In a second aspect, a VR display device is provided, comprising: a display module; and the above-mentioned optical system, located on the display side of the display module. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 This is a schematic diagram of the structure of the VR display device in the embodiment of this application. Figure 1 ;

[0018] Figure 2 This is a schematic diagram of the structure of the VR display device in the embodiment of this application. Figure 2 ;

[0019] Figure 3 This is a schematic diagram of the structure of the VR display device in the embodiment of this application. Figure 3 ;

[0020] Figure 4 This is a schematic diagram of the structure of the VR display device in the embodiment of this application. Figure 4 ;

[0021] Figure 5 This is a schematic diagram of the structure of the VR display device in the embodiment of this application. Figure 5 ;

[0022] Figure 6 This is a structural diagram of the VR display device in an embodiment of the present application. DETAILED DESCRIPTION

[0023] The technical solution of the present application will be described clearly and in detail below in conjunction with the drawings of the embodiments of the present application. Obviously, the embodiments described below are part of the embodiments of the present application rather than all the embodiments, and are only used to more clearly illustrate the technical solution of the present application. Therefore, they are only used as examples and cannot be used to limit the scope of protection of the present application. Based on the described embodiments of the present application, all other embodiments that can be obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0024] Unless otherwise defined, all technical and scientific terms used herein shall have the meanings commonly understood by those skilled in the art in the technical field of this application; the terms used herein are for the purpose of describing specific embodiments only and are not intended to limit this application; the terms "including" and "having" in the embodiments of this application and any variations thereof are intended to cover non-exclusive inclusions. The terms "first" and "second" in the embodiments of this application are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the embodiments of this application, unless otherwise stated, "multiple" means more than two.

[0025] In the embodiments of the present application, the orientations or positional relationships indicated by “longitudinal”, “transverse”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0026] In the embodiments of the present application, terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0027] In related technologies, such as Figure 6 As shown, the optical system adopting the folded optical path (hereinafter referred to as Pancake) scheme has the following light propagation process: the imaging light emitted by the display screen 100 first passes through the first polarizer 101 and becomes linearly polarized light (polarization direction p), the linearly polarized light passes through the first 1 / 4 wave plate 102 and becomes circularly polarized light, and then passes through the semi-transparent and semi-reflective film 103 to be emitted; the light emitted through the semi-transparent and semi-reflective film 103 enters the first lens 104, and then passes through the second 1 / 4 wave plate 105, and the circularly polarized light becomes linearly polarized light ( Polarization direction s), polarization direction s is perpendicular to polarization direction p; s-polarized light is reflected back by the reflective polarizer 106 that transmits p and reflects s, passes through the second 1 / 4 wave plate 105 again to become circularly polarized light, and enters the first lens 104, and then is reflected back by the semi-transparent and semi-reflective film 103 to form a folded light path; the folded light reflected back by the semi-transparent and semi-reflective film 103 passes through the second 1 / 4 wave plate 105 again to form p-polarized light, and passes through the reflective polarizer 106, passes through the second lens 107 and reaches the human eye 108.

[0028] Figure 6 The line with an arrow in the middle indicates the direction of light propagation.

[0029] As can be seen, the Pancake solution utilizes the principles of light refraction, reflection, and polarization to achieve a shorter optical path. Therefore, the Pancake solution offers superior performance in terms of lightweightness, image quality, and diopter adjustment, and is gaining increasing popularity in virtual display devices.

[0030] In related technologies, transflective films can be directly formed on the lens surface through an evaporation process, while polarizers and quarter-wave plates are sheet structures, and the optical system needs to provide a bearing surface for them to be bonded. Figure 6 As shown, one side of each lens is configured as a flat surface to facilitate lamination to the polarizer and quarter-wave plate on the side closest to the human eye. Since the display screen is generally flat, the polarizer and quarter-wave plate on the side closest to the display screen can be laminar to the display screen surface.

[0031] Since at least one side of the lens group of the optical system (i.e., the two lenses mentioned above) is designed as a plane to carry the polarizer and / or quarter-wave plate, it cannot be used as a usable surface for refracting light, thereby reducing the design freedom and limiting further optimization of imaging quality.

[0032] Based on this, the present application provides an optical system in which the surface of each lens is a curved surface, that is, all surfaces of the lens group of the optical system are usable surfaces that can be used for refracting light, thereby improving the design freedom and facilitating further optimization of imaging quality.

[0033] The lens group of the optical system may include one lens or multiple lenses.

[0034] The technical solution of this application will be clearly and completely described below with reference to the accompanying drawings.

[0035] According to some embodiments of the present application, an optical system is provided, such as Figure 1-5 As shown, it includes: a polarizing film material for converting imaging light into polarized light; at least one lens 20, the surface of each lens in the at least one lens 20 is a curved surface, and the polarized light is projected onto the at least one lens 20; a polarizing reflective film material for polarizing and reflecting the light emitted through the lens.

[0036] The imaging light can be the display light emitted from the display side of the display screen 1-0. The polarizing film material, at least one lens (lens group) 20 and the polarizing reflective film material can be assembled according to the parameters of the optical system such as the object distance and the spacing distance.

[0037] In some embodiments, the polarizing film includes a polarizer 1-1 and a first quarter-wave plate 1-2. Imaging light first passes through the first polarizer 1-1, becoming linearly polarized light. The linearly polarized light then passes through the first quarter-wave plate 1-2, becoming circularly polarized light. The polarizer 1-1 and the first quarter-wave plate 1-2 can be bonded together using an adhesive layer and then attached to the display screen, further facilitating system assembly. Depending on actual needs, the polarizing film may also include optical sheets with other functions.

[0038] The polarization directions of linearly polarized light include s and p directions. The polarization directions of circularly polarized light include left-handed and right-handed.

[0039] The at least one lens 20 may include a plurality of lenses, thereby improving the imaging capability of the optical system. Figure 1-5 In the illustrated example, the at least one lens 20 includes two lenses, a first lens 1 - 4 and a second lens 1 - 8. It is understandable that the number of lenses included in the plurality of lenses 20 may be three or more.

[0040] In some embodiments, multiple lenses can be bonded together by a bonding layer, that is, a bonding layer is provided between two adjacent lenses to bond them together, which is conducive to further compressing the thickness of the module and achieving lightness and thinness. Moreover, after the lenses are bonded together, the reflection between the lenses can be reduced, the chromatic aberration can be eliminated, and the imaging quality can be improved. Taking two lenses as an example, Figure 1-Figure 3 In the illustrated example, the first lens 1-4 and the second lens 1-8 are bonded together by a cementing layer 1-6.

[0041] It is understandable that, according to actual needs, a portion of the multiple lenses may be bonded together through a bonding layer, and a bonding layer may be provided between two adjacent lenses for bonding.

[0042] The material of the bonding layers 1-6 is a transparent material, which may include at least one of the following: natural resin optical glue, photosensitive glue, epoxy resin glue, methanol glue, thermal glue, optical photosensitive glue, etc.

[0043] In some embodiments, the outermost portion of at least one lens 20 near the polarizing film material (the first polarizer 1-1 and the first quarter-wave plate 1-2) can be formed into a semi-transparent and semi-reflective film by an evaporation film forming process. Part of the light projected onto the semi-transparent and semi-reflective film is emitted through the semi-transparent and semi-reflective film, and the other part is reflected back by the semi-transparent and semi-reflective film, thereby forming a folded light path. Figure 1-Figure 5 In the illustrated example, a semi-transmissive and semi-reflective film may be formed on the surface of the first lens 1-4 close to the display screen 1-0.

[0044] It is understandable that, in the case where at least one lens includes multiple lenses, the semi-transparent and semi-reflective films can also be provided on other curved surfaces of the multiple lenses except the outermost surfaces close to the polarizing film material, so as to form a folded light path.

[0045] The curved surface of the lens may mean that the surface of the lens is an aspherical surface or a free-form surface.

[0046] In some embodiments, the polarized reflective film material may include a second quarter-wave plate 1-11 and a reflective polarizer 1-12. The circularly polarized light emitted from the lens passes through the second quarter-wave plate 1-11, and the circularly polarized light becomes linearly polarized light again; the linearly polarized light is reflected back by the reflective polarizer 1-12, passes through the second quarter-wave plate 1-11 again to become circularly polarized light, and enters the lens, and is then reflected back by the semi-transparent and semi-reflective film to form a folded light path; the folded light reflected back by the semi-transparent and semi-reflective film passes through the second quarter-wave plate 1-11 again to form circularly polarized light. Due to the change in polarization direction, the circularly polarized light can pass through the reflective polarizer 1-12 and reach the human eye 1-15.

[0047] The second quarter-wave plate 1-11 and the reflective polarizer 1-12 can be bonded together by a bonding layer, which makes it easier to assemble the system.

[0048] It is understandable that the polarized reflective film material may also include optical sheets with other functions, such as an absorption polarizer 1-13 and an anti-reflection film 1-14.

[0049] When the polarized reflective film material includes an absorptive polarizer 1-13 and an antireflection film 1-14, light passing through the reflective polarizer 1-12 can sequentially pass through the absorptive polarizer 1-13 and the antireflection film 1-14 before reaching the human eye 1-15. That is, the second quarter-wave plate 1-11, the reflective polarizer 1-12, the absorptive polarizer 1-13, and the antireflection film 1-14 are arranged in this order. The absorptive polarizer 1-13 and the reflective polarizer 1-12 have the same polarization direction, which can absorb scattered light with inconsistent polarization directions, thereby improving the image quality reaching the human eye. The antireflection film 1-14 can reduce light reflection and increase light transmittance, ensuring that the human eye can observe a clear and bright image.

[0050] In some embodiments, see Figure 1-Figure 3 As shown, the second quarter-wave plate 1-11, the reflective polarizer 1-12, the absorptive polarizer 1-13, and the anti-reflection film 1-14 can be arranged in sequence and connected together via adhesive layers, which further facilitates system assembly. For example, the second quarter-wave plate 1-11 and the reflective polarizer 1-12 can be bonded together via a first adhesive layer, the reflective polarizer 1-12 and the absorptive polarizer 1-13 can be bonded together via a second adhesive layer, and the absorptive polarizer 1-13 and the anti-reflection film 1-14 can be bonded together via a third adhesive layer. For another example, the second quarter-wave plate, the reflective polarizer, the absorptive polarizer, and the anti-reflection film can also be bonded together in pairs via adhesive layers, the second quarter-wave plate and the reflective polarizer can be bonded together via a first adhesive layer, and the absorptive polarizer and the anti-reflection film can be bonded together via a third adhesive layer. For another example, the second quarter-wave plate, reflective polarizer, and absorptive polarizer are bonded together using adhesive layers. Specifically, the second quarter-wave plate and reflective polarizer can be bonded together using a first adhesive layer, while the reflective polarizer and absorptive polarizer can be bonded together using a second adhesive layer. The antireflection film is assembled as a separate sheet.

[0051] According to some embodiments of the present application, the polarized reflective film material (the first quarter-wave plate 1-1 and the polarizer 1-2) is located on the side of at least one lens 20 that is away from the polarized film material (the second quarter-wave plate 1-11, the reflective polarizer 1-12, the absorptive polarizer 1-13 and the anti-reflection film 1-14). In this case, the light passes through at least one lens and then is projected onto the polarized reflective film material, thereby providing a longer optical path and improving the imaging quality while keeping the thickness of the module unchanged.

[0052] In some embodiments, the polarized reflective film material (1-11, 1-12, 1-13, 1-14) is located on the side of at least one lens 20 away from the polarized film material (1-1 and 1-2), and the semi-transparent and semi-reflective film is located on the outermost side of at least one lens 20 close to the polarized film material (1-1 and 1-2), so that the folded light formed by the light reflected by the polarized reflective film material (1-11, 1-12, 1-13, 1-14) passes through all lenses and is projected onto the semi-transparent and semi-reflective film. The folded light reflected back by the semi-transparent and semi-reflective film passes through all lenses again and is projected onto the semi-transparent and semi-reflective film before being emitted. Therefore, when the thickness of the module remains unchanged, a longer folded light path can be provided to improve the imaging quality.

[0053] The technical solution of the present application designs the surface of each lens in the lens group of the optical system as a curved surface. As a result, the surfaces of all lenses are usable surfaces that can be used for refracting light, thereby improving the design freedom and facilitating further optimization of imaging quality.

[0054] In some embodiments, see Figure 1 、 2 and Figure 4 As shown, a carrier plate 1-0 independent of the lens group can be provided to provide a carrier surface (plane) for the polarized reflective film (1-11, 1-12, 1-13, 1-14), thereby enabling the lens group to be implemented without having to reserve a plane as a carrier surface for carrying the polarized reflective film.

[0055] The carrier plate 1 - 0 is a plate-like structure with a flat surface. The polarized reflective film material is attached to the surface of the carrier plate 1 - 0 .

[0056] The carrier plate 1 - 0 may be, for example but not limited to, a flat glass plate or a resin plate.

[0057] In some embodiments, all sheets of the polarizing reflective film can be pre-bonded together using an adhesive layer before being attached to the surface of the carrier plate. For example, in a polarizing reflective film comprising a second quarter-wave plate 1-11, a reflective polarizer 1-12, an absorptive polarizer 1-13, and an anti-reflection film 1-14, adhesive layers are provided between each of the second quarter-wave plate 1-11, the reflective polarizer 1-12, the absorptive polarizer 1-13, and the anti-reflection film 1-14 to form a four-in-one film. The bonding method for the sheets of the polarizing reflective film has been described above and will not be repeated here.

[0058] The carrier plate 1-0 can be located on the side of at least one lens 20 that is away from the polarizing film (1-1, 1-2), as described above. This can provide a longer optical path and improve imaging quality while maintaining the same module thickness. In this case, when the optical system includes multiple lenses, all of the lenses can be bonded together using a bonding layer. That is, a bonding layer is provided between each adjacent lens in the multiple lenses for bonding. This helps to further reduce the thickness of the module, achieving lightweight and thinness. Furthermore, after the lenses are bonded together, they can reduce inter-lens reflections, eliminate chromatic aberration, and improve imaging quality.

[0059] In the case that the optical system includes a plurality of lenses, the carrier plate may also be located between two lenses and the two lenses may be spaced apart.

[0060] Furthermore, if there are multiple lenses on the same side of the carrier plate, the multiple lenses on the same side of the carrier plate can also be bonded together through a bonding layer, which is conducive to further compressing the thickness of the module and achieving lightweight and thinness. After the lenses are bonded, they can reduce inter-lens reflections, eliminate chromatic aberration, and improve imaging quality.

[0061] In addition to independently providing a supporting plate for supporting the polarized reflective film material, the polarized reflective film material can also be attached to the curved surface of the lens.

[0062] According to some embodiments of the present application, see Figure 3 and Figure 5 As shown, at least one lens 20 includes a target lens, one surface of which is a convex surface protruding away from its optical center, and a polarized reflective film (1-11, 1-12, 1-13, 1-14) is attached to the convex surface of the target lens.

[0063] Therefore, by using the curved surface film bonding technology to bond the polarizing reflective film material to the convex surface of one of the lenses, it is also possible to achieve that the lens group does not need to reserve a plane as a bearing surface for bearing the polarizing reflective film material, and the polarizing reflective film material can be well bonded to the convex surface, which not only does not affect the optical performance, but also can reduce lens reflection, eliminate chromatic aberration, and improve imaging quality.

[0064] The convex surface of the lens may refer to a surface of the lens that protrudes outward toward a side away from the optical center of the lens.

[0065] In some embodiments, see Figure 3 and Figure 5As shown, at least one lens of the optical system includes multiple lenses, and the target lens is the outermost lens farthest from the polarizing film (1-1, 1-2) among the multiple lenses, that is, the target lens is the second lens 1-8. One of the surfaces of the target lens is the outer surface facing away from the polarizing film, and this outer surface is convex. The polarizing reflective film (1-11, 1-12, 1-13, 1-14) is attached to the outer surface of the second lens 1-8. In other words, the polarizing reflective film is attached to the outermost surface of the lens group facing away from the polarizing film. In this case, light passes through multiple lenses before being projected onto the polarizing reflective film, thereby providing a longer optical path and improving imaging quality while maintaining the thickness of the module.

[0066] In some embodiments, the polarizing reflective film is attached to the outermost surface (convex surface) of at least one lens away from the polarizing film, and the semi-transparent and semi-reflective film is located on the outermost surface (curved surface) of at least one lens close to the polarizing film, so that the folded light formed by the light reflected by the polarizing reflective film passes through all lenses and is projected onto the semi-transparent and semi-reflective film. The folded light reflected back by the semi-transparent and semi-reflective film passes through all lenses again and is projected onto the semi-transparent and semi-reflective film before being emitted. Therefore, while the thickness of the module remains unchanged, a longer folded light path can be provided to improve the imaging quality.

[0067] When at least one lens includes multiple lenses, the polarizing reflective film can also be bonded to the surfaces of other lenses except the outermost lens facing away from the polarizing film, as long as the lens surface bonded to the polarizing reflective film is convex.

[0068] When the polarizing reflective film is applied to a convex surface of a lens, the film can be applied to the convex surface of the target lens first, and then multiple lenses can be bonded together using a bonding layer. That is, two adjacent lenses can be directly bonded together using a bonding layer. This helps further reduce the thickness of the module, achieving a lighter and thinner design. Furthermore, after the lenses are bonded together, they can reduce inter-lens reflections, eliminate chromatic aberration, and improve image quality.

[0069] According to some embodiments of the present application, a VR display device is provided, including: a display module; and the above-mentioned optical system, located on the display side of the display module.

[0070] By adopting this optical system, both sides of each lens in the lens assembly are usable, thereby increasing design freedom and enhancing imaging capabilities. The process is simple to implement, facilitating widespread application. Furthermore, the use of a cemented lens assembly further optimizes and reduces module thickness, improves system light efficiency, mitigates ghosting, and further reduces product size and weight, while also enhancing user comfort and immersion.

[0071] The VR display device can be a head-mounted VR display device, VR glasses, an all-in-one VR device, etc.

[0072] For ease of description and understanding, the technical solution of this application will be described below with reference to several specific examples. In the following examples, the optical system comprises a lens assembly consisting of two lenses. For lens assemblies with one lens, or three or more lenses, implementations can be achieved by making reasonable modifications or adjustments to the examples described below without requiring inventive effort.

[0073] exist Figure 1 In the illustrated example, the VR display device includes a display module 10, a lens group (ie, at least one lens of an optical system) 20, and a polarized reflection module 30. The display module 10 may be an LCD, an OLED, or other display modules.

[0074] The display module 10 includes a display screen 1-0, a polarizer 1-1 and a first quarter wave plate 1-2. The polarizer 1-1 and the first quarter wave plate 1-2 are two-in-one film materials (i.e., they are pre-bonded together by an adhesive layer) and are attached to the display screen 1-0 at a set angle.

[0075] The optical system includes a polarizer 1-1 and a first quarter-wave plate 1-2 attached to the display screen 1-0, a lens assembly 20, and a polarization reflection module 30. The slow axis of the first quarter-wave plate 1-2 is at a 45° or -45° angle with the absorption axis of the polarizer 1-1 (the fast axis of the first quarter-wave plate 1-2 is at a 45° or -45° angle with the transmission axis of the polarizer 1-1). This allows linearly polarized light polarized by the polarizer 1-1 to become circularly polarized light after passing through the first quarter-wave plate 1-2.

[0076] The lens group 20 includes a first lens 1-4 and a second lens 1-8. 1-3 is a surface of the first lens 1-4, which is an aspherical surface or a free-form surface. The surface 1-3 is formed into a semi-transparent and semi-reflective film by an evaporation process. 1-5 is another surface of the first lens 1-4, which is an aspherical surface or a free-form surface. 1-7 is a surface of the second lens 1-8, which is an aspherical surface or a free-form surface. 1-9 is another surface of the second lens 1-8, which is an aspherical surface or a free-form surface. The surface curvature of the surface 1-5 of the first lens 1-4 and the surface 1-7 of the second lens 1-8 are consistent to facilitate gluing. 1-6 is a gluing layer, and the first lens 1-4 and the second lens 1-8 are bonded by the gluing layer 1-6. The gluing layer uses liquid optical glue or other glue such as optical glue.

[0077] Polarized reflective module 30 includes a carrier plate 1-10 and polarized reflective films sequentially attached to the surface of carrier plate 1-10. The polarized reflective films are a four-in-one structure consisting of films 1-11, 1-12, 1-13, and 1-14: film 1-11 is a second quarter-wave plate, film 1-12 is a reflective polarizer, film 1-13 is an absorptive polarizer, and film 1-14 is an antireflection film. The four-in-one films are attached to the surface of carrier plate 1-10 at a predetermined angle.

[0078] The display module 10, lens group 20 and polarized reflection module 30 are assembled together according to the spacing and inter-lens distance of the optical system. The lens gluing can compress the module thickness, and the film material is attached to an independent carrier plate. The lens group does not need to reserve a flat surface for film attachment, which provides an extra available surface during design, thereby improving design freedom and enhancing the imaging capability of the optical system.

[0079] The display principle of VR display device is:

[0080] The imaging light emitted by the display screen 1-0 first passes through the polarizer 1-1 and becomes linearly polarized light (polarization direction p). The linearly polarized light passes through the first quarter-wave plate 1-2 and becomes circularly polarized light, and is projected onto the semi-transparent and semi-reflective film for emission; the circularly polarized light emitted through the semi-transparent and semi-reflective film enters the lens group 20, and then passes through the second quarter-wave plate 1-11, and the circularly polarized light becomes linearly polarized light (polarization direction s), and the polarization direction s is perpendicular to the polarization direction p; the s-polarized light is reflected back by the reflective polarizer 1-12 that transmits p and reflects s, and passes through the second quarter-wave plate 1-11 again to become circularly polarized light, and enters the lens group 20, and then is reflected back by the semi-transparent and semi-reflective film to form a folded light path; the folded light reflected back by the semi-transparent and semi-reflective film passes through the second quarter-wave plate 1-11 again to form p-polarized light, and passes through the reflective polarizer 1-12 that transmits p and reflects s, the absorptive polarizer 1-13 and the anti-reflection film 1-14 to reach the human eye 1-15.

[0081] exist Figure 1 In the illustrated example, the four-in-one film is attached to the surface of the carrier plate 1-10 that is away from the lens group 20. Figure 2 As shown, the four-in-one film material can also be attached to the surface of the carrier plate 1-10 close to the lens group 20.

[0082] exist Figure 3 In the illustrated example, the display module 10 and the lens group 20 are Figure 1 The implementation method of the illustrated example is the same, except that the four-in-one film materials 1-10, 1-11, 1-12, and 1-13 are bonded to the surface 1-9 of the second lens 1-8 using curved surface bonding technology, and the surface 1-9 of the second lens 1-8 is set to be convex.

[0083] exist Figure 1 and Figure 3 In the illustrated example, the two lenses of the lens assembly 20 are cemented together.

[0084] exist Figure 4 In the illustrated example, the display module 10 and the polarized reflection module 30 are connected to Figure 1 The implementation of the illustrated example is the same, except that the first lenses 1-4 and the second lenses 1-8 of the lens group 20 are spaced apart. It is understandable that the carrier plate can also be arranged between the first lenses and the second lenses.

[0085] exist Figure 5 In the example shown, Figure 4 The difference from the illustrated example is that the four-in-one film materials 1-10, 1-11, 1-12, and 1-13 are bonded to the surface 1-9 of the second lens 1-8 using curved surface bonding technology.

[0086] Figure 2-Figure 5 In the illustrated example, the display principle of the virtual display device is the same as Figure 1 The examples shown are similar and will not be described in detail.

[0087] Figure 1-Figure 5 The arrowhead in the middle indicates the direction of light propagation. Figure 1-Figure 5 In the illustrated example, even if the sheets are bonded using a bonding layer, the sheets are shown separated by a distance for illustration. For example, even if the second quarter-wave plate 1-11, reflective polarizer 1-12, absorptive polarizer 1-13 and anti-reflection film 1-14 of the polarized reflective film are bonded in pairs by a bonding layer to form a four-in-one film, the second quarter-wave plate 1-11, reflective polarizer 1-12, absorptive polarizer 1-13 and anti-reflection film 1-14 are still shown separated by a distance for illustration only for ease of understanding.

[0088] Finally, it should be noted that the above embodiments are only partial embodiments of the technical solutions of the present application, which are used to clearly illustrate the technical solutions of the present application, and are not intended to limit the technical solutions of the present application. Under the inventive concept of the present application, ordinary technicians in this field can still modify the technical solutions described in the above embodiments, or make equivalent or equivalent replacements for some or all of the technical features therein; and these modifications or replacements do not deviate the essence of the corresponding technical solutions from the concept of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and description of the present application.

Claims

1. An optical system, characterized in that: include: Polarizing film, used to convert imaging light into polarized light; at least one lens, wherein a surface of each lens of the at least one lens is a curved surface, and the polarized light is projected onto the at least one lens; The polarized reflective film material is used to polarize and reflect the light emitted from the lens.

2. The optical system according to claim 1, wherein: The polarizing reflective film is located on a side of the at least one lens that is away from the polarizing film.

3. The optical system according to claim 1, wherein: Also includes: A supporting plate, the polarized reflective film material is attached to the surface of the supporting plate.

4. The optical system according to claim 3, wherein: The supporting plate is located on a side of the at least one lens away from the polarizing film material.

5. The optical system according to claim 4, wherein: The at least one lens includes a plurality of lenses, and two adjacent lenses in the plurality of lenses are connected by a bonding layer.

6. The optical system according to claim 3, wherein: The at least one lens includes a plurality of lenses, the carrying plate is located between two lenses, and the two lenses are spaced apart.

7. The optical system according to claim 1, wherein: The at least one lens includes a target lens, one surface of the target lens is a convex surface protruding in a direction away from the optical center thereof, and the polarized reflective film material is attached to the convex surface of the target lens.

8. The optical system according to claim 7, wherein: The at least one lens includes multiple lenses, the target lens is the outermost lens among the multiple lenses that is farthest away from the polarizing film material, one of the surfaces of the target lens is the outer surface facing away from the polarizing film material, and the polarizing reflective film material is adhered to the outer surface of the target lens.

9. The optical system according to claim 1, wherein: The at least one lens includes a plurality of lenses, and two adjacent lenses in the plurality of lenses are connected by a bonding layer.

10. The optical system according to any one of claims 1 to 9, characterized in that The polarized reflective film material comprises a quarter wave plate, a reflective polarizer, an absorptive polarizer and an anti-reflection film which are arranged in sequence and connected by a glue layer.

11. A VR display device, characterized in that: include: Display module; The optical system according to any one of claims 1 to 10 is located on the display side of the display module.

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