Optical lens group, display device and electronic equipment

Abstract

The utility model provides an optical lens group, a display device and electronic equipment, and the optical lens group comprises a first lens group which is used for carrying out the path adjustment and aberration correction of light of a light source, and forming first light; the polarization splitting prism is provided with a first reflecting surface, an incident surface and an emergent surface which are connected in sequence, a polarization splitting surface is embedded in the polarization splitting prism, and the first reflecting surface is parallel to the emergent surface; the first lens group is parallel to the incident surface, and the first light can penetrate through the incident surface and is reflected by the first reflecting surface and the polarization beam splitting surface in sequence to form second light; the reflector is used for reflecting the second light to form third light; the included angle between the surface, directly facing the reflector, of the polarization splitting prism and the polarization splitting surface is smaller than 45 degrees. A second lens group facing the exit surface; and the polarization beam splitting surface can transmit the third light to enable the third light to sequentially pass through the emergent surface and the second lens group.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical technology, in particular to an optical lens, a display device and an electronic device. BACKGROUND

[0002] In near-eye display systems such as Augmented Reality (AR) and Virtual Reality (VR), an optical lens as a key component in a one-dimensional waveguide imaging system is mainly used to magnify the image from a micro display and ensure that the image can be clearly transmitted to the user's eyes. In order to achieve high-quality image magnification and transmission, a cuboid-shaped polarization beam splitter is currently used for polarization splitting, reflection and refraction processing to ensure that the image finally presented on the user's retina is clear and not distorted.

[0003] However, since the refractive power needs to be arranged around the polarization beam splitter in the shape of a cuboid, the volume of the optical lens is large, the lens barrel is long, which increases the overall size and weight of the device, and also affects the wearing comfort. CONTENT OF THE INVENTION

[0004] The purpose of the embodiments of the present application is to provide an optical lens, a display device and an electronic device.

[0005] To solve the above technical problems, the embodiments of the present application provide the following technical solutions:

[0006] The first aspect of the present application provides an optical lens, comprising:

[0007] A first lens group is used for path adjustment and aberration correction of light rays from a light source to form first light rays;

[0008] A polarization beam splitter has a first reflecting surface, an incident surface and an exit surface connected in sequence, and a polarization splitting surface is embedded inside the polarization beam splitter. The first reflecting surface is parallel to the exit surface. The first lens group is parallel to the incident surface, and the first light rays can pass through the incident surface, sequentially reflect off the first reflecting surface and the polarization splitting surface to form second light rays;

[0009] A mirror is used to reflect the second light rays to form third light rays. The angle between the surface of the polarization beam splitter opposite to the mirror and the polarization splitting surface is less than 45°;

[0010] A second lens group is opposite to the exit surface. The polarization splitting surface can transmit the third light rays so that the third light rays sequentially pass through the exit surface and the second lens group.

[0011] In some implementation forms of the first aspect of the application, the reflecting mirror is a plano-convex lens, and the reflecting mirror has an air gap between the plane of the reflecting mirror and the polarization beam splitting prism; the plane of the reflecting mirror is provided with a wave plate, and the convex surface of the reflecting mirror is provided with a total reflection film.

[0012] In some implementation forms of the first aspect of the application, the polarization beam splitting prism comprises:

[0013] A first polarization beam splitting prism body is located between the reflecting mirror and the second lens group; the first polarization beam splitting prism has the entrance surface, the first reflecting surface and a connecting surface;

[0014] A second polarization beam splitting prism body is located between the first polarization beam splitting prism body and the second lens group; the second polarization beam splitting prism body has the exit surface and a butt joint surface;

[0015] A polarization beam splitting film is connected with the butt joint surface and the connecting surface respectively to form a polarization beam splitting surface.

[0016] In some implementation forms of the first aspect of the application, the first lens group comprises:

[0017] The first lens is a plano-convex lens; the plane of the first lens is used to be opposite to the micro display, and the plane of the first lens is provided with a polarizer.

[0018] In some implementation forms of the first aspect of the application, the first lens group comprises:

[0019] The first lens, the second lens and the third lens are sequentially distributed along the optical axis from the light source to the polarization beam splitting prism;

[0020] The first surface of the third lens opposite to the entrance surface is a plane; and / or at least one lens in the first lens group is formed by cementing a positive lens and a negative lens.

[0021] In some implementation forms of the first aspect of the application, the surface type of the lens in the first lens group is a spherical surface or an aspherical surface; and / or,

[0022] The surface type of the reflecting mirror is a spherical surface, an aspherical surface or a free-form surface; and / or,

[0023] The surface type of the lens in the second lens group is a spherical surface or an aspherical surface.

[0024] The second aspect of the application provides a display device, comprising:

[0025] A micro display is used to emit a light source;

[0026] An optical lens group comprises:

[0027] a first lens group, which adjusts the path and aberration of the light rays from the light source to form first light rays;

[0028] a polarization beam splitter prism, which has a first reflecting surface, an incident surface and an exit surface connected in sequence, and has a polarization beam splitting surface embedded in the polarization beam splitter prism, the first reflecting surface being parallel to the exit surface; the first lens group being parallel to the incident surface, the first light rays being able to pass through the incident surface and be reflected by the first reflecting surface and the polarization beam splitting surface in sequence to form second light rays;

[0029] a mirror, which is used to reflect the second light rays to form third light rays; the surface of the polarization beam splitter prism opposite to the mirror being at an angle of less than 45° with the polarization beam splitting surface;

[0030] a second lens group, which is opposite to the exit surface; the polarization beam splitting surface being able to transmit the third light rays so that the third light rays pass through the exit surface and the second lens group in sequence.

[0031] In some modified embodiments of the second aspect of the present application, further comprising:

[0032] a waveguide system, which has a coupling-in end and a plurality of coupling-out ends, the coupling-in end being opposite to the second lens group and being used to receive fourth light rays passing through the second lens group; the plurality of coupling-out ends being arranged along the propagation direction of the fourth light rays in the waveguide system.

[0033] In some modified embodiments of the second aspect of the present application, the distance between the micro display and the first lens group is less than 10 mm; and / or,

[0034] the focal length of the optical lens group is 15 mm < f < 25 mm.

[0035] The third aspect of the present application provides an electronic device, comprising:

[0036] a display device, comprising:

[0037] a micro display, which is used to emit light rays;

[0038] an optical lens group, comprising:

[0039] a first lens group, which adjusts the path and aberration of the light rays from the light source to form first light rays;

[0040] a polarization beam splitter prism, which has a first reflecting surface, an incident surface and an exit surface connected in sequence, and has a polarization beam splitting surface embedded in the polarization beam splitter prism, the first reflecting surface being parallel to the exit surface; the first lens group being parallel to the incident surface, the first light rays being able to pass through the incident surface and be reflected by the first reflecting surface and the polarization beam splitting surface in sequence to form second light rays;

[0041] a mirror for reflecting the second light to form a third light; the surface of the polarizing beam splitter opposite to the mirror forms an angle less than 45° with the polarizing surface;

[0042] a second lens group opposite to the exit surface; the polarizing surface is capable of transmitting the third light so that the third light passes through the exit surface and the second lens group in sequence. BRIEF DESCRIPTION OF DRAWINGS

[0043] The above and other objects, features and advantages of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which a number of embodiments of the present application are shown by way of example, and wherein like reference numerals refer to like elements throughout. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the present application. In the drawings:

[0044] Figure 1 a structural schematic diagram of one embodiment of the optical lens set of the present application is shown schematically;

[0045] Figure 2 a structural schematic diagram of another embodiment of the optical lens set of the present application is shown schematically;

[0046] Figure 3 a structural schematic diagram of one embodiment of the display device of the present application is shown schematically;

[0047] Figure 4 a structural schematic diagram of another embodiment of the display device of the present application is shown schematically.

[0048] BRIEF DESCRIPTION OF DRAWINGS

[0049] 1, first lens group; 11, first lens; 12, second lens; 13, third lens; 2, polarizing beam splitter; 21, first polarizing beam splitter body; 22, second polarizing beam splitter body; 3, mirror; 4, second lens group; 5, micro display; 6, waveguide system. DETAILED DESCRIPTION

[0050] Exemplary embodiments of the present disclosure will be described hereinafter with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be embodied in various forms without being limited by the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

[0051] It should be noted that unless otherwise specified, technical terms or scientific terms used in the present application should be understood as their ordinary meanings to those skilled in the art to which the present application pertains.

[0052] As Figure 1 and Figure 2 The first aspect of the present application provides an optical lens, comprising:

[0053] A first lens group 1 is used to adjust the path of light from a light source (such as a micro display 5 or a micro light emitting diode, etc.) and correct aberrations to ensure the quality of the subsequent processed light, thereby ensuring the clarity and accuracy of the final image. The first lens group 1 can be parallel to the light-emitting side of the light source and the entrance surface of the polarization beam splitter. In order to enhance the light transmission effect, the central axis of the first lens group 1 can coincide with the normal line of the entrance surface to ensure that the light can be vertically incident, thereby smoothly transmitting from the first lens group 1 to the polarization beam splitter 2 for subsequent processing.

[0054] A polarization beam splitter 2 has a first reflecting surface, an entrance surface and an exit surface connected in sequence. The polarization beam splitter 2 is embedded with a polarization beam splitting surface inside. The first reflecting surface is parallel to the exit surface. The first lens group 1 is parallel to the entrance surface, and the first light can pass through the entrance surface, sequentially reflect the first reflecting surface and the polarization beam splitting surface to form the second light.

[0055] A mirror 3 is used to reflect the second light to form the third light. The angle between the surface of the polarization beam splitter 2 opposite to the mirror 3 and the polarization beam splitting surface is less than 45°.

[0056] A second lens group 4 is opposite to the exit surface. The polarization beam splitting surface can transmit the third light to sequentially pass through the exit surface and the second lens group 4.

[0057] The first lens group 1 is used to adjust the path of light from a light source (such as a micro display 5 or a micro light emitting diode, etc.) and correct aberrations to ensure the quality of the subsequent processed light, thereby ensuring the clarity and accuracy of the final image. The first lens group 1 can be parallel to the light-emitting side of the light source and the entrance surface of the polarization beam splitter. In order to enhance the light transmission effect, the central axis of the first lens group 1 can coincide with the normal line of the entrance surface to ensure that the light can be vertically incident, thereby smoothly transmitting from the first lens group 1 to the polarization beam splitter 2 for subsequent processing.

[0058] The first lens group 1 can be composed of one or more lenses. The specific number of the first lens group 1 can be designed according to the design parameters (such as the radius of curvature, the thickness, etc.) of each lens to achieve the required optical performance. This flexible design can be optimized for different application scenarios to achieve the best aberration correction effect while minimizing the overall device size and weight.

[0059] The polarization beam splitter 2 can realize polarization beam splitting, reflection and transmission of light to ensure correct transmission of image information. The polarization beam splitter 2 can be embedded with a polarization beam splitting film inside to form a polarization beam splitting surface. The polarization beam splitting film can be selected from different types such as multi-layer dielectric film or metal wire grid structure, which can be selected according to the required wavelength range, incident angle and optical performance requirements.

[0060] The surface of the polarization beam splitter prism 2 connected with the incident surface can be provided with a reflective film to form a first reflective surface. The material of the reflective film can be selected from aluminum, silver, or the like. The first reflective surface of the polarization beam splitter prism 2 is parallel to the exit surface, ensuring that the light propagates along the expected path after multiple reflections and refractions, reducing aberration or other optical errors caused by angle deviation, while reducing the thickness of the prism and achieving a more compact structural layout.

[0061] The mirror 3 is used to reflect the light processed by the polarization beam splitter prism 2, change its propagation direction, and compress the transverse space. The surface of the polarization beam splitter prism 2 opposite to the mirror 3 can be non-coplanar with the first reflective surface to flexibly adjust the optical path; or the surface of the polarization beam splitter prism 2 opposite to the mirror 3 can be coplanar with the first reflective surface to achieve a compact layout design, in which case the included angle between the first reflective surface and the polarization beam splitting surface is less than 45°, increasing the number of light path folding to effectively utilize the space and control the direction of the light. The mirror 3 can be selected from a plane mirror 3 or a mirror 3 with a specific curvature, etc. to meet different application requirements.

[0062] The second lens group 4 is used to perform the final focusing processing on the light processed by the polarization beam splitter prism 2 and the mirror 3, so that it can be clearly projected onto the user's retina. The polarization beam splitter prism 2 is located between the second lens group 4 and the mirror 3, and the second lens group 4 can be opposite to the exit surface, ensuring that the light from the polarization beam splitter prism 2 can pass through the second lens group 4 and be focused. The second lens group 4 can include one or more lenses. The second lens group 4 can be spaced apart from or bonded to the polarization beam splitter prism 2. The specific number of the second lens group 4 can be designed according to the design parameters (such as the radius of curvature, the thickness, etc.) of each lens to achieve the required optical performance. In the case where the second lens group 4 contains only one lens, the lens of the second lens group 4 can be a plano-convex lens, and the plane of the lens of the second lens group 4 can be close to the exit surface to achieve the convergence of the light. Alternatively, the lens of the second lens group 4 can be a concave-convex lens, and the convex surface of the lens of the second lens group 4 can be close to the exit surface to provide better focusing effect in a limited space, which is suitable for applications requiring high-precision focusing.

[0063] The light emitted by the light source forms a first light after passing through the first lens group 1, the first light enters the polarization beam splitter prism 2 through the incident surface of the polarization beam splitter prism 2, and then forms a second light after being reflected by the first reflective surface and the polarization beam splitting surface in sequence. The mirror 3 emits the second light to form a third light, the third light reenters the polarization beam splitter prism 2, is transmitted through the polarization beam splitting surface, and then passes out of the polarization beam splitter prism 2, and is processed by the second lens group 4.

[0064] The optical lens provided by the application ensures that light can directly and efficiently enter the polarization beam splitter 2, and reduces unnecessary reflection and refraction paths, because the first lens group 1 is parallel to and directly opposite the incident surface of the polarization beam splitter 2. The surface of the polarization beam splitter 2 directly opposite the mirror 3 has an angle of less than 45° with the polarization beam splitting surface. After the first light enters the incident surface, it sequentially passes through the first reflecting surface and the functional surface twice to form the second light. That is, the first light realizes light path folding through two internal reflections of the polarization beam splitter 2, forms a turnaround path, compresses the space requirement in the optical axis direction, and enables the second light to be efficiently transmitted in a smaller space. The third light formed after the second light is reflected by the mirror 3 returns to the polarization beam splitting surface, passes through the exit surface through the transmission of the polarization beam splitting surface, and is finally processed by the second lens group 4. The compact light path design realizes the propagation according to the preset light path in a limited space, optimizes the space utilization, improves the integration and portability of the optical lens, shortens the lens barrel length, reduces the overall size and weight of the equipment, and improves the wearing comfort.

[0065] As shown in Figure 1 and Figure 2 in some embodiments, the mirror 3 is a plano-convex lens, and the plane of the mirror 3 has an air gap with the polarization beam splitter 2; the plane of the mirror 3 is provided with a wave plate, and the convex surface of the mirror 3 is provided with a total reflection film.

[0066] The plane of the mirror 3 and the polarization beam splitter 2 can maintain an air gap of 50-200 μm to reduce energy loss caused by material absorption and scattering, and facilitate adjustment and calibration of the positional relationship of the components. The wave plate is arranged on the plane of the plano-convex lens, which can be a quartz λ / 4 wave plate, or an independent wave plate (such as a polymer liquid crystal phase retardation plate) bonded by optical glue, etc. The working wavelength of the wave plate needs to match the light source. The wave plate can change the polarization state of the passing light. When linearly polarized light passes through the wave plate, it will be converted into circularly polarized light or elliptically polarized light, and vice versa. The convex surface of the plano-convex lens can be coated with a total reflection film to form a second reflecting surface, which ensures that all light incident on the second reflecting surface is completely reflected back to improve the light energy utilization rate and reduce energy loss.

[0067] When the convex total reflection film reflects the light, the curvature of the plano-convex lens can pre-focus the light beam, compensate for the defocus amount of the second lens group 4, and reduce the number of lenses. Further compress the lateral size of the system to realize a more compact design.

[0068] As shown in Figure 1 and Figure 2 in some embodiments, the polarization beam splitter 2 includes:

[0069] The first polarizing beam splitter 2 is located between the mirror 3 and the second lens group 4; the first polarizing beam splitter 2 has the incident surface, the first reflecting surface and a connecting surface;

[0070] The second polarizing beam splitter 2 is located between the first polarizing beam splitter 2 and the second lens group 4; the second polarizing beam splitter 2 has the exit surface and a counter surface;

[0071] The polarizing beam splitting film is connected with the counter surface and the connecting surface respectively to form a polarizing beam splitting surface.

[0072] The connecting surface can be rectangular, circular or other shapes. The counter surface can have the same shape and size as the connecting surface and face it directly, and the size of the counter surface is the same as that of the connecting surface to ensure complete coverage of the connecting area. The polarizing beam splitting film is located between the connecting surface and the counter surface, and the polarizing beam splitting film can have the same shape as the connecting surface, and the size of the polarizing beam splitting film can be equal to or slightly smaller than the size of the connecting surface to avoid unnecessary energy loss caused by exceeding the boundary and achieve high-efficiency polarizing beam splitting function. The polarizing beam splitting film can be bonded to the connecting surface and the counter surface by optical glue; or the polarizing beam splitting film can be deposited on the connecting surface or the counter surface, and then the connecting surface and the counter surface are bonded together to ensure that the film layer is tightly attached and will not be displaced due to environmental changes.

[0073] By embedding the polarizing beam splitting film between the connecting surface and the counter surface, the firm combination of the polarizing beam splitting film with the connecting surface and the counter surface is effectively ensured, the optical performance fluctuation caused by environmental changes is reduced, and the long-term stability of the system is improved.

[0074] As shown in Figure 1 and Figure 2 In some embodiments, the first lens group 1 includes:

[0075] The first lens 11 is a plano-convex lens; the flat surface of the first lens 11 is used to face the micro display 5, and the flat surface of the first lens 11 is provided with a polarizer.

[0076] The plane of the first lens 11 can be bonded with a polarizing sheet by optical adhesive; or, in the case that the material of the plano-convex lens is compatible with the material of the polarizing sheet, a polarizing film layer can be deposited on the plane side of the plano-convex lens, and the deposition method can adopt physical vapor deposition or chemical vapor deposition, etc. By setting the polarizing sheet on the plane side of the plano-convex lens, the polarization state of the incident light can be accurately controlled, which is suitable for AR / VR display systems and other systems that require high-precision polarization processing. The polarizing sheet can effectively filter out unnecessary polarization components, reducing the influence of stray light and reflected light, thereby improving image contrast and clarity. The polarizing sheet can ensure that only light with a specific polarization direction passes through, reducing unnecessary energy loss and improving light energy utilization. The convex design of the plano-convex lens can preliminarily focus the light when it enters the system, reducing the burden on subsequent optical components and improving overall optical efficiency. By reasonably selecting the curvature radius and other parameters of the plano-convex lens, aberrations can be effectively reduced, improving imaging quality. By directly setting the polarizing sheet on the plane side of the plano-convex lens, a more compact design can be achieved, reducing the overall volume and weight of the system and improving wear comfort. This integrated design reduces the need for separate installation of the polarizing sheet, simplifies the system structure, and reduces manufacturing costs.

[0077] As shown in Figure 1 and Figure 2 In some embodiments, the first lens group 1 includes:

[0078] The first lens 11, the second lens 12, and the third lens 13 are sequentially distributed along the optical axis from the light source to the polarizing beam splitter 2.

[0079] Among them, the first surface of the third lens 13 opposite to the entrance surface is a plane; and / or at least one lens in the first lens group 1 is a composite lens composed of a positive lens and a negative lens.

[0080] The first lens 11 is used to preliminarily adjust the light path and correct aberrations. The second lens 12 is used to further correct aberrations, optimize the light path, and reduce chromatic aberrations and other advanced aberrations. The second lens 12 can be a plano-convex lens, and the plane of the second lens 12 can be close to the first lens 11, and the convex surface of the second lens 12 can be close to the third lens 13. Alternatively, the second lens 12 can be a composite lens composed of a positive lens and a negative lens, and the concave surface of the composite lens can be close to the first lens 11, and the convex surface of the composite lens can be close to the third lens 13. The third lens 13 adjusts the light for the last time to ensure that the light can efficiently enter the polarizing beam splitter 2. The third lens 13 can be a plano-concave lens. The plane of the third lens 13 is parallel to the entrance surface, ensuring that the light can efficiently enter the polarizing beam splitter 2.

[0081] By introducing multiple lenses in the first lens group 1 and making at least one lens be a positive-negative lens cemented together, the optical performance of the system can be effectively enhanced, while optimizing the space utilization, reducing the overall volume and weight of the system, and improving the wearing comfort. Not only the imaging quality is improved, but also a more compact spatial layout is achieved, which is suitable for near-eye display systems with strict requirements on volume, weight and imaging quality. Arranging multiple lenses along the optical axis in sequence and making the first surface of the third lens 13 be a plane helps to achieve a compact spatial layout, reduce the overall volume and weight of the system, and improve the wearing comfort.

[0082] As shown in Figure 1 and Figure 2 in some embodiments, the surface type of the lenses in the first lens group 1 is spherical or aspherical; and / or,

[0083] the surface type of the mirror 3 is spherical, aspherical or free-form surface; and / or,

[0084] the surface type of the lenses in the second lens group 4 is spherical or aspherical.

[0085] In the case where the first lens group 1 includes multiple lenses, all the lenses can be aspherical lenses; or, all the lenses can be spherical lenses; or, part of the lenses can be aspherical lenses and part of the lenses can be spherical lenses. Spherical lenses are simple to manufacture and have lower cost. Aspherical lenses can significantly reduce aberrations such as spherical aberration and coma, and improve the imaging quality. Specific selection can be made according to actual needs. The surface type of the lenses in the second lens group 4 can refer to the surface type of the lenses in the first lens group 1. Spherical mirrors 3 are simple to manufacture, and aspherical mirrors 3 can effectively reduce aberrations and improve the imaging quality. Free-form mirrors 3 can provide extremely high imaging quality and flexibility in complex optical systems, and are suitable for applications requiring high-precision correction of aberrations.

[0086] By selecting appropriate surface types in the first lens group 1, the mirror 3 and the second lens group 4, the optical performance of the system can be effectively enhanced, while optimizing the space utilization, reducing the overall volume and weight of the system, and improving the wearing comfort. This design not only improves the imaging quality, but also achieves a more compact spatial layout, which is suitable for near-eye display systems with strict requirements on volume, weight and imaging quality.

[0087] Embodiment 1

[0088] As shown in Figure 1As shown, the first lens group 1 includes the first lens 11, the second lens 12 and the third lens 13 arranged in sequence along the optical axis from the light source to the polarization beam-splitting prism 2; the first lens 11 is a plano-convex lens, the plane S14 of the first lens is close to the light source, and the convex surface S13 of the first lens is opposite to the second lens 12; the second lens 12 is a plano-convex lens, the plane S12 of the second lens is opposite to the first lens 11, and the convex surface S11 of the second lens is opposite to the third lens 13; the third lens 13 is a plano-concave lens, the concave surface S10 of the third lens is opposite to the second lens 12, and the plane S9 of the third lens is opposite to the entrance surface.

[0089] The reflector 3 is a plano-concave lens, the plane S7 of the reflector is close to the polarization beam-splitting prism 2, the plane S7 of the reflector is attached with a wave plate, and the convex surface S8 of the reflector is provided with a full-reflection film.

[0090] The second lens group 4 includes one meniscus lens, the convex surface S2 of the second lens group is close to the exit surface and spaced apart from the exit surface, and the concave surface S1 of the second lens group is opposite to the coupling-in end of the waveguide system 6.

[0091] All the surfaces in the embodiment are spherical surfaces.

[0092] In the imaging process, the light emitted by the micro display 5 is polarized after passing through the polarizer attached to the plane S14 of the first lens, and is refracted into the polarization beam-splitting prism 2 through the first lens 11, the second lens 12 and the third lens 13. After total reflection at the first reflecting surface S5 of the polarization beam-splitting prism 2, the light is reflected at the polarization beam-splitting surface S4, and is emitted from the surface S6 opposite to the reflector 3 of the polarization beam-splitting prism 2. After the polarization state is changed at the plane S7 of the reflector, the light is reflected at the convex surface S8 of the reflector, and is again changed in polarization state at the plane S7 of the reflector before entering the surface S6 opposite to the reflector 3 of the polarization beam-splitting prism 2. The light is transmitted from the polarization beam-splitting surface S4 and emitted from the exit surface S3, and is emitted from the exit pupil after passing through the second lens group 4.

[0093] A set of optical parameters is provided in the above system according to the experimental example 1, as shown in Table 1 and Table 2.

[0094] Table 1: Parameters of each optical surface in the imaging system provided in the experimental example 1

[0095]

[0096] Table 2: Eccentricity parameters of the polarization beam-splitting prism in the experimental example 1 (relative to the surface S3)

[0097] Surface of a polarizing beam splitter X-decentering Y-decentering Z-decentering Alpha tilt S4 0 4.52 0 22.39 S6 0 8.40 3.44 -44.72

[0098] Example 2

[0099] As Figure 2As shown, the first lens group 1 includes the first lens 11, the second lens 12 and the third lens 13 arranged in sequence along the optical axis from the light source to the polarizing beam splitter 2; the first lens 11 is a plano-convex lens, the plane S14 of the first lens is close to the light source, and the convex surface S13 of the first lens is opposite to the second lens 12; the second lens 12 is a compound lens, the concave surface S12 of the second lens is opposite to the first lens 11, the second lens 12 has the intermediate concave surface S11, and the convex surface S10 of the second lens is opposite to the third lens 13; the third lens 13 is a plano-concave lens, the concave surface S9 of the third lens is opposite to the second lens 12, and the plane S8 of the third lens is opposite to the entrance surface.

[0100] The reflector 3 is selected to be an aspherical surface, and the reflector 3 has the second reflecting surface S7 and is close to the polarizing beam splitter 2.

[0101] The second lens group 4 includes a plano-convex lens, the plane S2 of the second lens group is bonded to the exit surface, and the convex surface S1 of the second lens group is opposite to the coupling-in end of the waveguide system 6.

[0102] The surfaces of all the lenses of the first lens group 1 and the second lens group 4 of the optical lens group of the embodiment 2 are selected to be spherical surfaces.

[0103] In the imaging process, the light emitted by the micro display 5 is polarized by the polarizer attached to the plane S14 of the first lens, is refracted by the first lens 11, the second lens 12 and the third lens 13, enters the polarizing beam splitter 2, is totally reflected by the first reflecting surface S5 of the polarizing beam splitter 2, is reflected by the polarizing surface S4, is emitted from the surface S6 of the polarizing beam splitter 2 opposite to the reflector 3, is reflected by the aspherical reflector 3, enters the surface S6 of the polarizing beam splitter 2 opposite to the reflector 3, is transmitted by the polarizing surface S4, is emitted from the exit surface S3, and is emitted from the exit pupil after passing through the second lens group 4.

[0104] The experiment example 2 provides a set of optical parameters according to the above system, as shown in Tables 3-5.

[0105] Table 3: Parameters of each optical surface in the imaging system provided by the second embodiment

[0106]

[0107]

[0108] Table 4: Optical parameters of the aspherical surface reflector

[0109]

[0110] Table 5: Eccentricity parameters of the polarizing beam splitter in the embodiment 2 (relative to the surface S3)

[0111] Surface of a polarizing beam splitter X-decentering Y-decentering Z-decentering Alpha tilt S4 0 4.81 0 22.67 S6 0 8.43 5.32 -45.29

[0112] wherein the aspherical surface equation is:

[0113]

[0114] wherein c is the reciprocal of the radius of curvature;

[0115] r is the radial distance of a point on the surface;

[0116] k is the conic constant;

[0117] Ai is the high-order term coefficient.

[0118] As shown in Figure 3 and Figure 4 The second aspect of the present application provides a display device, comprising:

[0119] a micro display 5 for emitting a light source;

[0120] an optical lens group, comprising:

[0121] a first lens group 1 for adjusting the path and aberration of the light source light to form a first light;

[0122] a polarization beam splitter 2 having a first reflecting surface, an incident surface and an exit surface connected in sequence, the polarization beam splitter 2 is embedded with a polarization beam splitting surface inside, the first reflecting surface is parallel to the exit surface; the first lens group 1 is parallel to the incident surface, the first light can pass through the incident surface, sequentially pass through the first reflecting surface and the polarization beam splitting surface to form a second light;

[0123] a mirror 3 for reflecting the second light to form a third light; the surface of the polarization beam splitter 2 opposite to the mirror 3 is less than 45° with the polarization beam splitting surface;

[0124] a second lens group 4 opposite to the exit surface; the polarization beam splitting surface can transmit the third light to make the third light sequentially pass through the exit surface and the second lens group 4.

[0125] The micro display 5 can be a liquid crystal display or an organic light emitting diode, etc.

[0126] The display device provided in the second aspect of the present application comprises the optical mirror group provided in the first aspect. Since the first lens group 1 is parallel to and directly opposite the entrance surface of the polarization beam splitter 2, the light can directly and efficiently enter the polarization beam splitter 2, reducing unnecessary reflection and refraction paths. The surface of the polarization beam splitter 2 directly opposite the mirror 3 is at an angle of less than 45° with the polarization beam splitting surface. After the first light enters the entrance surface, it sequentially passes through the first reflection surface and the functional surface twice, forming the second light. That is, the first light is folded by two internal reflections of the polarization beam splitter 2, forming a return path, which compresses the space requirement in the optical axis direction, so that the second light can be efficiently transmitted in a smaller space. After the second light is reflected by the mirror 3, the third light is returned to the polarization beam splitting surface and transmitted through the exit surface of the polarization beam splitting surface, and finally the light is processed by the second lens group 4. This compact optical path design realizes the propagation according to the preset optical path in a limited space, optimizes the space utilization, improves the integration and portability of the optical mirror group, shortens the length of the lens barrel, reduces the overall size and weight of the device, and improves the wearing comfort.

[0127] As shown in Figure 3 and Figure 4 in some embodiments, further comprising:

[0128] a waveguide system 6 having a coupling-in end and a plurality of coupling-out ends, the coupling-in end being opposite to the second lens group 4, the coupling-in end being configured to receive the fourth light transmitted through the second lens group 4; the plurality of coupling-out ends being arranged along the propagation direction of the fourth light in the waveguide system 6.

[0129] The waveguide system 6 is configured to be perpendicular to the user's visual axis. The coupling-in end is configured to guide the fourth light out of the second lens group 4 into the waveguide system 6. The coupling-out end is configured to gradually couple the light guided into the waveguide system 6 out to the user's eye or sensor. The plurality of coupling-out ends can be uniformly distributed or arranged in a specific pattern to ensure that the image information is uniformly distributed throughout the field of view. By utilizing the total internal reflection characteristics of the waveguide system 6, the energy loss of the light during transmission is minimized, and the overall optical efficiency is improved. By reasonably arranging the plurality of coupling-out ends, high-quality image information can be provided at different positions in the user's field of view, expanding the field of view. The design of the waveguide system 6 makes the entire optical system more compact, reduces the overall size and weight of the device, and improves the wearing comfort.

[0130] As shown in Figure 3 and Figure 4 in some embodiments, the distance between the micro display 5 and the first lens group 1 is less than 10 mm; and / or,

[0131] The focal length of the optical mirror group is 15 mm < f < 25 mm.

[0132] The precise spacing between the micro display 5 and the first lens group 1 can be ensured by a precise mechanical structure design or by using flexible connectors. The spacing between the micro display 5 and the first lens group 1 can be 9 mm, 8 mm, 7 mm, 6 mm, 5 mm, 4 mm or even closer, etc.

[0133] The appropriate lens type can be selected according to the required focal length range, such as a plano-convex lens, a double-convex lens or other types of aspherical lens, and the curvature radius, thickness and other parameters of each lens are reasonably configured to meet the range requirement of focal length. The focal length f of the optical lens group can be 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 21 mm, 22 mm, 23 mm or 24 mm, etc.

[0134] By controlling the spacing between the micro display 5 and the first lens group 1 to be less than 10 mm and setting the focal length of the optical lens group to be in the range of 15 mm < f < 25 mm, not only the compactness of the system is realized, but also the imaging quality and optical efficiency are optimized.

[0135] The third aspect of the present application provides an electronic device, comprising:

[0136] A display device, such as shown in Figure 3 and Figure 4 comprises:

[0137] A micro display 5 for emitting a light source;

[0138] An optical lens group comprising:

[0139] A first lens group 1 for adjusting the path and correcting the aberration of the light rays of the light source to form a first light ray;

[0140] A polarization beam splitter 2 having a first reflecting surface, an incident surface and an exit surface connected in sequence, and a polarization beam splitting surface embedded inside the polarization beam splitter 2, the first reflecting surface being parallel to the exit surface; the first lens group 1 is parallel to the incident surface, and the first light ray can pass through the incident surface, sequentially reflect through the first reflecting surface and the polarization beam splitting surface to form a second light ray;

[0141] A mirror 3 for reflecting the second light ray to form a third light ray; the angle between the surface of the polarization beam splitter 2 opposite to the mirror 3 and the polarization beam splitting surface is less than 45°;

[0142] A second lens group 4 opposite to the exit surface; the polarization beam splitting surface can transmit the third light ray to sequentially pass through the exit surface and the second lens group 4.

[0143] The electronic device can be an AR glasses, a VR headset, a head-mounted display, etc.

[0144] The electronic device provided in the third aspect of the present application comprises the display device provided in the second aspect, and the display device comprises the optical mirror group provided in the first aspect, and the optical mirror group comprises the optical mirror group provided in the first aspect. Since the first lens group 1 is parallel to and directly opposite the entrance surface of the polarization beam splitting prism 2, it is ensured that the light can directly and efficiently enter the polarization beam splitting prism 2, and the unnecessary reflection and refraction path is reduced. The surface of the polarization beam splitting prism 2 which is directly opposite the mirror 3 has an angle of less than 45° with the polarization beam splitting surface. After the first light enters the entrance surface, it sequentially passes through the first reflection surface and the functional surface twice to form the second light. That is, the first light realizes light path folding through two internal reflections of the polarization beam splitting prism 2, forms a return path, compresses the space requirement in the optical axis direction, and enables the second light to be efficiently transmitted in a smaller space. The second light returns to the polarization beam splitting surface after being reflected by the mirror 3 to form the third light, passes through the exit surface through the transmission of the polarization beam splitting surface, and finally is processed by the second lens group 4. This compact light path design realizes the propagation according to the preset light path in a limited space, optimizes the space utilization, improves the integration and portability of the optical mirror group, shortens the length of the lens barrel, reduces the overall size and weight of the device, and improves the wearing comfort.

[0145] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An optical lens, characterized in that, Comprising: a first lens group for path adjustment and aberration correction of light rays of a light source to form first light rays; a polarization beam-splitting prism having a first reflecting surface, an incident surface and an exit surface connected in sequence, the polarization beam-splitting prism having a polarization beam-splitting surface embedded therein, the first reflecting surface being parallel to the exit surface; the first lens group being parallel to the incident surface, the first light rays being able to pass through the incident surface and be reflected by the first reflecting surface and the polarization beam-splitting surface in sequence to form second light rays; a mirror for reflecting the second light rays to form third light rays; an angle between a surface of the polarization beam-splitting prism opposite to the mirror and the polarization beam-splitting surface being less than 45°; a second lens group opposite to the exit surface; the polarization beam-splitting surface being able to transmit the third light rays so that the third light rays pass through the exit surface and the second lens group in sequence.

2. The optical mirror group according to claim 1, wherein: the mirror is a plano-convex lens, an air gap being provided between a plane of the mirror and the polarization beam-splitting prism; a wave plate being provided on the plane of the mirror, and a total reflection film being provided on a convex surface of the mirror.

3. The optical mirror according to claim 1, wherein, the polarization beam-splitting prism comprises: a first polarization beam-splitting prism body between the mirror and the second lens group; the first polarization beam-splitting prism having the incident surface, the first reflecting surface and a connecting surface; a second polarization beam-splitting prism body between the first polarization beam-splitting prism body and the second lens group; the second polarization beam-splitting prism body having the exit surface and a butt joint surface; a polarization beam-splitting film connected with the butt joint surface and the connecting surface respectively to form the polarization beam-splitting surface.

4. The optical mirror according to claim 1, wherein, the first lens group comprises: a first lens, the first lens being a plano-convex lens; a plane of the first lens being used to be opposite to a micro display, and a polarizer being provided on the plane of the first lens.

5. The optical mirror according to claim 4, wherein, the first lens group comprises: the first lens, a second lens and a third lens distributed in sequence along an optical axis from the light source to the polarization beam-splitting prism; wherein, a first surface of the third lens opposite to the incident surface is a plane; and / or, at least one lens in the first lens group is formed by cementing a positive lens and a negative lens.

6. The optical mirror group according to claim 1, wherein: a surface type of a lens in the first lens group is a spherical surface or an aspherical surface; and / or, a surface type of the mirror is a spherical surface, an aspherical surface or a free-form surface; and / or, a surface type of a lens in the second lens group is a spherical surface or an aspherical surface.

7. A display device, characterized by comprising: Comprising: a micro display for emitting a light source; an optical mirror group comprising: a first lens group for path adjustment and aberration correction of light rays of the light source to form first light rays; a polarization beam-splitting prism having a first reflecting surface, an incident surface and an exit surface connected in sequence, the polarization beam-splitting prism having a polarization beam-splitting surface embedded therein, the first reflecting surface being parallel to the exit surface; the first lens group being parallel to the incident surface, the first light rays being able to pass through the incident surface and be reflected by the first reflecting surface and the polarization beam-splitting surface in sequence to form second light rays; a mirror for reflecting the second light to form a third light; an angle between a surface of the polarization beam splitter prism opposite to the mirror and the polarization beam splitting surface is less than 45°; a second lens group opposite to the exit surface; the polarization beam splitting surface is capable of transmitting the third light to make the third light sequentially pass through the exit surface and the second lens group.

8. The display device of claim 7, wherein, Further comprising: a waveguide system having a coupling-in end and a plurality of coupling-out ends, the coupling-in end opposite to the polarization beam splitter prism, the coupling-in end for receiving a fourth light passing through the second lens group; the plurality of coupling-out ends arranged along a propagation direction of the fourth light in the waveguide system.

9. The display device of claim 7, wherein: a distance between the micro display and the first lens group is less than 10 mm; and / or a focal length of the optical lens group is 15 mm < f < 25 mm.

10. An electronic device, comprising: Comprising: a display device comprising: a micro display for emitting a light source; an optical lens group comprising: a first lens group for adjusting a path and correcting aberration of the light source light to form a first light; a polarization beam splitter prism having a first reflecting surface, an entrance surface and an exit surface connected in sequence, the polarization beam splitter prism having a polarization beam splitting surface embedded therein, the first reflecting surface parallel to the exit surface; the first lens group parallel to the entrance surface, the first light capable of passing through the entrance surface, sequentially passing through the first reflecting surface and the polarization beam splitting surface to form a second light; a mirror for reflecting the second light to form a third light; an angle between a surface of the polarization beam splitter prism opposite to the mirror and the polarization beam splitting surface is less than 45°; a second lens group opposite to the exit surface; the polarization beam splitting surface is capable of transmitting the third light to make the third light sequentially pass through the exit surface and the second lens group.

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