Virtual reality system

Abstract

The application discloses a virtual reality system, comprising a visual lens and a positioning lens, wherein the visual lens comprises, along a first optical axis, from a first side away from a screen to a second side close to the screen, a first element group comprising a reflective polarizing element, a quarter-wave plate and a first lens with positive refractive power, wherein a first side or a second side of the first lens is a plane, a second element group comprising a second lens with positive refractive power, and a third element group comprising a third lens with positive refractive power; the positioning lens comprises, along a second optical axis, from an object side to an image side, a first lens with negative refractive power, a second lens with negative refractive power, a third lens with positive refractive power, a fourth lens with refractive power, a fifth lens with positive refractive power, a sixth lens with negative refractive power, a seventh lens with positive refractive power and an eighth lens with positive refractive power.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical elements, in particular to a virtual reality system. BACKGROUND

[0002] In recent years, the metaverse industry is constantly upgrading and replacing, and the way humans interact will change from 2D interaction to more efficient 3D interaction. People pay more attention to the interactive experience with virtual digital space. XR (Extended Reality) technology refers to an environment that combines reality and virtuality and can be interacted with computers and wearable devices. It uses VR (Virtual Reality), AR (Augmented Reality), and MR (Mixed Reality) and other visual interaction technologies to integrate virtual content with real scenes, which can change the way people interact with the real world and bring users a new immersive experience. XR technology has a wide range of applications in many fields, such as entertainment, education, medicine, industry, and construction.

[0003] The perception interaction function is essential for the establishment and application of the XR ecosystem, and the tracking and positioning function is the basis and premise. The tracking and positioning technology relies on the mutual cooperation of the visual lens and the positioning lens of the virtual reality system, but its recognition ability under different environmental light and its ability to embed the fusion of the virtual picture still need to be strengthened.

[0004] Therefore, how to optimize the optical design scheme of the virtual reality system so that the positioning lens can be suitable for positioning under different environmental light sources and strengthen the overall effect of the visual fusion is one of the technical problems to be solved at present. SUMMARY

[0005] According to the embodiments of the present application, a virtual reality system is provided, comprising a viewing lens and a positioning lens, wherein the viewing lens comprises, along a first optical axis from a first side away from a screen to a second side close to the screen, a first element group comprising a reflective polarizing element, a quarter-wave plate and a first lens with positive refractive power, wherein a first side or a second side of the first lens is a plane, a second element group comprising a second lens with positive refractive power, and a third element group comprising a third lens with positive refractive power; the positioning lens comprises, along a second optical axis from an object side to an image side, a first lens with negative refractive power, a second lens with negative refractive power, a third lens with positive refractive power, a fourth lens with refractive power, a fifth lens with positive refractive power, a sixth lens with negative refractive power, a seventh lens with positive refractive power, and an eighth lens with positive refractive power; the virtual reality system satisfies: -11.0 < (f2a + f3a) / (R3a + R5a) < 0.3; 11.2 < (CT5 + CT7) / CT6 < 13.3; 1.5 < ImgH / f < 2.2; and 2.2 < TTLa / TTL < 4.7; wherein f2a is an effective focal length of the second lens, f3a is an effective focal length of the third lens, R3a is a radius of curvature of the first side of the second lens, R5a is a radius of curvature of the first side of the third lens, CT5 is a center thickness of the fifth lens, CT7 is a center thickness of the seventh lens, CT6 is a center thickness of the sixth lens, ImgH is a half of an image height corresponding to a maximum field of view angle of the positioning lens, f is a total effective focal length of the positioning lens, TTLa is a distance from the first side of the first element group to the screen of the viewing lens on the first optical axis, and TTL is a distance from the object side of the first lens to an imaging surface of the positioning lens on the second optical axis.

[0006] In one or more embodiments, the viewing lens satisfies: -1.2 < Rna / (R3a + R4a) < 1.0, wherein R3a is a radius of curvature of the first side of the second lens, R4a is a radius of curvature of the second side of the second lens, Rna is a minimum value of the radii of curvature of the first side and the second side of the first lens, and n = 1 or 2.

[0007] In one or more embodiments, the viewing lens satisfies: 0.2 < f1a / V1a / CT1a < 8.0, wherein f1a is an effective focal length of the first lens, V1a is an Abbe number of the first lens, and CT1a is a center thickness of the first lens.

[0008] In one or more embodiments, the viewing lens satisfies: -4.0 < (R4a + R5a) / (CT2a + CT3a) < -1.9, wherein R4a is a radius of curvature of the second side of the second lens, R5a is a radius of curvature of the first side of the third lens, CT2a is a center thickness of the second lens, and CT3a is a center thickness of the third lens.

[0009] In one or more embodiments, the visual lens satisfies: 2.0 < (f2a / N2a) / (f3a / N3a) < 11.0, where f2a is the effective focal length of the second lens, N2a is the refractive index of the second lens, f3a is the effective focal length of the third lens, and N3a is the refractive index of the third lens.

[0010] In one or more embodiments, the visual lens satisfies: -7.5 < R6a / R5a+R4a / R3a < 7.6, where R6a is the radius of curvature of the second side of the third lens, R5a is the radius of curvature of the first side of the third lens, R4a is the radius of curvature of the second side of the second lens, and R3a is the radius of curvature of the first side of the second lens.

[0011] In one or more embodiments, the visual lens satisfies: 29 mm < TDa < 40.0 mm, where TDa is the distance from the second side of the third element group to the screen of the visual lens on the first optical axis.

[0012] In one or more embodiments, the visual lens satisfies: 0.5 < CT3a / (CT1a+CT2a) < 2.5, where CT3a is the center thickness of the third lens, CT1a is the center thickness of the first lens, and CT2a is the center thickness of the second lens.

[0013] In one or more embodiments, the positioning lens satisfies: -0.2 < f / f1 < -0.15, where f is the total effective focal length of the positioning lens, and f1 is the effective focal length of the first lens.

[0014] In one or more embodiments, the positioning lens satisfies: -13.5 < (R11+R12) / f6 < -4.3, where R11 is the radius of curvature of the object side of the sixth lens, R12 is the radius of curvature of the image side of the sixth lens, and f6 is the effective focal length of the sixth lens.

[0015] In one or more embodiments, the positioning lens satisfies: 3.7 < TTL / (CT5+CT7) < 4.3, where TTL is the distance from the object side of the first lens to the imaging surface of the positioning lens on the second optical axis, CT5 is the center thickness of the fifth lens, and CT7 is the center thickness of the seventh lens.

[0016] In one or more embodiments, the positioning lens satisfies: 5.8 < DT11 / CT1 / N1 < 12.5, where DT11 is the effective half aperture of the object side of the first lens, CT1 is the center thickness of the first lens, and N1 is the refractive index of the first lens.

[0017] In one or more embodiments, the positioning lens satisfies: -2.5 < f1 / N1 / (f3 / N3) < -1.5, where f1 is the effective focal length of the first lens, N1 is the refractive index of the first lens, f3 is the effective focal length of the third lens, and N3 is the refractive index of the third lens.

[0018] In one or more embodiments, the positioning lens satisfies: 2.0 < (SAG11 + SAG12) / (SAG81 + SAG82) < 6.0, where SAG11 is the distance between the intersection of the object side of the first lens on the second optical axis and the vertex of the maximum effective half aperture on the second optical axis, SAG12 is the distance between the intersection of the image side of the first lens on the second optical axis and the vertex of the maximum effective half aperture on the second optical axis, SAG81 is the distance between the intersection of the object side of the eighth lens on the second optical axis and the vertex of the maximum effective half aperture on the second optical axis, and SAG82 is the distance between the intersection of the image side of the eighth lens on the second optical axis and the vertex of the maximum effective half aperture on the second optical axis.

[0019] In one or more embodiments, the positioning lens satisfies: -0.8 < (f5 + f6) / f < 1.4, where f5 is the effective focal length of the fifth lens, f6 is the effective focal length of the sixth lens, and f is the total effective focal length of the positioning lens.

[0020] In one or more embodiments, the positioning lens satisfies: -0.8 < f6 / f3 (N6 / N3) < -0.2; N3 > 1.6 and N6 > 1.6; where f3 is the effective focal length of the third lens, f6 is the effective focal length of the sixth lens, N3 is the refractive index of the third lens, and N6 is the refractive index of the sixth lens.

[0021] According to an embodiment of the present application, a virtual reality system may include three catadioptric eyepiece lenses and eight ultra-wide-angle positioning lenses. The eyepiece lenses utilize polarizing elements to achieve optical path refraction, facilitating a lightweight and thin device design. The first and second lenses of the positioning lenses have negative optical powers, which facilitates increasing the system's field of view and broadening the range of perspective capture of real-world images. While enhancing the user's wearing experience, limiting the ratio of the sum of the effective focal lengths of the second and third lenses in the eyepiece lens to the sum of the curvature radii of the corresponding lens surfaces away from the screen effectively shortens the overall lens length. Controlling the ratio of the median thickness of the fifth and seventh lenses, and the median thickness of the sixth lens, in the positioning lens facilitates controlling the shape and median thickness of the rear lens segments of the eyepiece lens and the positioning lens. Furthermore, by constraining the ratio of the maximum half-image height to the focal length of the positioning lens, the positioning field of view and incident light are maximized, making it more suitable for positioning under different ambient light sources and enhancing the overall integration effect with the visual field. Furthermore, controlling the overall length ratio of the eyepiece lens to the positioning lens facilitates spatial layout within the entire device and avoids interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0023] Figure 1 A schematic diagram showing the composition of a virtual reality system provided according to an embodiment of the present application is shown;

[0024] Figure 2 Schematic diagram of the structure of the visual lens according to the first embodiment of the present application is shown;

[0025] Figures 3A to 3C axial chromatic aberration curve, astigmatism curve, and distortion curve of the visual lens according to Example 1 of the present application are respectively shown;

[0026] Figure 4 A schematic structural diagram of a visual lens according to the second embodiment of the present application is shown;

[0027] Figures 5A to 5C axial chromatic aberration curve, astigmatism curve, and distortion curve of the visual lens according to the second embodiment of the present application are respectively shown;

[0028] Figure 6 Schematic diagram of the structure of the visual lens according to the third embodiment of the present application is shown;

[0029] Figures 7A to 7C axial chromatic aberration curve, astigmatism curve, and distortion curve of the visual lens according to Example 3 of the present application are respectively shown;

[0030] Figure 8 A schematic structural diagram of a positioning lens according to a fourth embodiment of the present application is shown;

[0031] Figures 9A to 9C axial chromatic aberration curve, a distortion curve, and a magnification chromatic aberration curve of the positioning lens according to Embodiment Four of the present application are shown respectively;

[0032] Figure 10 a structural schematic diagram of a positioning lens according to Embodiment Five of the present application is shown;

[0033] Figures 11A to 11C axial chromatic aberration curve, a distortion curve, and a magnification chromatic aberration curve of the positioning lens according to Embodiment Five of the present application are shown respectively;

[0034] Figure 12 a structural schematic diagram of a positioning lens according to Embodiment Six of the present application is shown;

[0035] Figures 13A to 13C axial chromatic aberration curve, a distortion curve, and a magnification chromatic aberration curve of the positioning lens according to Embodiment Six of the present application are shown respectively;

[0036] Figure 14 a structural schematic diagram of a positioning lens according to Embodiment Seven of the present application is shown; and

[0037] Figures 15A to 15C axial chromatic aberration curve, a distortion curve, and a magnification chromatic aberration curve of the positioning lens according to Embodiment Seven of the present application are shown respectively. DETAILED DESCRIPTION

[0038] For a better understanding of the present application, various aspects of the present application will be described in more detail below with reference to the accompanying drawings. It is to be noted that the detailed description is only a description of exemplary embodiments of the present application and does not limit the scope of the present application in any way. Throughout the specification, like reference numerals refer to like elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0039] It should be noted that in the present specification, the expressions first, second, third, etc. are merely used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, the first lens discussed below can also be referred to as the second lens or the first lens without departing from the teachings of the present application.

[0040] In the drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shape of the spherical surface or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical surface or aspherical surface is not limited to the shape of the spherical surface or aspherical surface shown in the drawings. The drawings are merely examples and are not drawn strictly to scale.

[0041] In the present disclosure, the paraxial region refers to a region near the optical axis. If a lens surface is convex and the position of the convex surface is not specified, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the position of the concave surface is not specified, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is referred to as the object side surface of the lens, and the surface of each lens closest to the image plane is referred to as the image side surface of the lens.

[0042] It should also be understood that the words "comprise," "comprising," "include," "including," and / or "has," "having" when used in this specification have the same meaning as the word "comprise" or "comprising" and are inclusive or open-ended and do not exclude additional non-enumerated features, elements, components, and / or steps.

[0043] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0044] It should be noted that the embodiments and features of the embodiments in the present application can be combined with each other without conflict. The following embodiments only express several embodiments of the present application, which are described in detail and specifically, but should not be understood as limitations to the scope of the patent of the present application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application.

[0045] The features, principles, and other aspects of the present application are described in detail below.

[0046] Reference Figure 1As shown, the virtual reality system 100 according to the exemplary embodiments of the present application can include a visual lens 110 and a positioning lens 120. The combination of the visual lens 110 and the positioning lens 120 can realize the fusion of virtual content and real scene. The visual lens 110 provides virtual feeling, and the positioning lens 120 provides real environment, which increases the boundary and interaction while providing immersion. Specifically, the positioning lens 120 can be used to image the real scene, and the formed real image is transmitted to the display screen in the form of electrical signal; the image surface of the visual lens 110 can be located on the display screen, and the visual lens 110 can be used to project the virtual image on the display screen and the above-mentioned real image transmitted to the display screen, such as projecting into the user's eyes, so as to realize that the user sees the picture of virtual and real combination, and improve the user's immersion.

[0047] The visual lens 110 can be configured as a catadioptric visual optical system, and the number thereof can be one or more, and the positioning lens 120 can be configured as a video perspective optical system, and the number thereof can be one or more. In an example, the virtual reality system 100 can include two visual lenses 110 arranged symmetrically. In an example, the virtual reality system 100 further includes a body, the visual lens 110 can be arranged on the inner side of the body, and the positioning lens 120 can be arranged on the outer side of the body.

[0048] In the exemplary embodiments, the visual lens 110 can include a first element group, a second element group and a third element group arranged in sequence from a first side to a second side along a first optical axis, wherein the first element group can include a first lens, a reflective polarizing element and a quarter wave plate, the second element group can include a second lens, and the third element group can include a third lens. There can be air gaps between the first element group and the second element group, and between the second element group and the third element group.

[0049] In the exemplary embodiments, the first side can be a side away from the screen, and the second side can be a side close to the screen. Accordingly, the first side surface of each element (the first lens, the second lens, the reflective polarizing element, the quarter wave plate, the third lens, etc.) in the visual lens 110 can be the surface away from the screen, and the second side surface can be the surface close to the screen.

[0050] In the exemplary embodiments, the first lens, the second lens and the third lens all have positive refractive power. The use of lenses with positive refractive power can balance aberration, and the lenses can be used for divergence or convergence, so as to meet the performance requirements of a large field of view with only three lenses.

[0051] In an example embodiment, the first side or the second side of the first lens of the viewing lens 110 is attached with a reflective polarizing element and a quarter wave plate. The first side or the second side of the first lens can be a flat surface. The reflective polarizing element can reflect light in a certain direction and can transmit light orthogonal to the reflected light when the light passes through the reflective polarizing element. The quarter wave plate can be used to convert between circularly polarized light and linearly polarized light to achieve catadioptric, which is beneficial to shorten the length of the viewing lens 110.

[0052] In an example embodiment, the first side or the second side of the first lens, the second lens and the third lens of the viewing lens 110 can be aspherical surfaces. Aspherical lenses have better curvature radius characteristics, which have the advantages of improving distortion aberration and improving astigmatism aberration. By using aspherical lenses, aberrations that occur during imaging can be eliminated as much as possible, thereby improving the imaging quality.

[0053] In an example embodiment, the viewing lens 110 can further include a partial reflection element, which can be, for example, a partial reflection layer attached or coated on the first side or the second side of the second lens. The partial reflection layer has a semi-transmissive and semi-reflective effect on light. Image light from the display screen is finally projected to the user's eye after multiple refractions and reflections through the third lens, the second lens, the reflective polarizing element, the quarter wave plate, the first lens, and the partial reflection element. By providing the partial reflection layer on the first side or the second side of the second lens, in combination with the reflective polarizing element and the quarter wave plate, the light can be folded and reflected multiple times, thereby effectively reducing the length of the viewing lens.

[0054] In an example embodiment, the positioning lens 120 can include, in order from the object side to the image side along the second optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens. Adjacent two lenses among the first lens to the eighth lens can have an air gap therebetween.

[0055] The virtual reality system 100 according to the example embodiment of the present application can be used in various virtual reality display devices, such as a VR head-mounted device, an MR head-mounted device, or an AR electronic device, etc.

[0056] In the exemplary embodiment of the present application, the virtual reality system comprises a viewing lens and a positioning lens. The viewing lens comprises, in order from the first side to the second side along the first optical axis, a first element group, a second element group and a third element group. The first element group comprises a reflective polarizing element, a quarter-wave plate and a first lens with positive refractive power. The second element group comprises a second lens with positive refractive power. The third element group comprises a third lens with positive refractive power. The positioning lens comprises, in order from the object side to the image side along the second optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens. The first lens and the second lens have negative refractive power. The third lens has positive refractive power. The fourth lens can have positive or negative refractive power. The fifth lens has positive refractive power. The sixth lens has negative refractive power. The seventh lens and the eighth lens have positive refractive power. The real image formed by the positioning lens is transmitted to the display screen in the form of an electrical signal. The viewing lens is used to project the virtual image on the display screen and transmit the real image on the display screen.

[0057] The virtual reality system according to the exemplary embodiment of the present application can satisfy the following conditions: -11.0 < (f2a + f3a) / (R3a + R5a) < 0.3; 11.2 < (CT5 + CT7) / CT6 < 13.3; 1.5 < ImgH / f < 2.2; and 2.2 < TTLa / TTL < 4.7; wherein f2a is the effective focal length of the second lens, f3a is the effective focal length of the third lens, R3a is the radius of curvature of the first side surface of the second lens, R5a is the radius of curvature of the first side surface of the third lens, CT5 is the center thickness of the fifth lens, CT7 is the center thickness of the seventh lens, CT6 is the center thickness of the sixth lens, ImgH is half of the image height corresponding to the maximum field of view angle of the positioning lens, f is the total effective focal length of the positioning lens, TTLa is the distance from the first side surface of the first element group to the screen of the viewing lens along the first optical axis, and TTL is the distance from the object side surface of the first lens to the imaging surface of the positioning lens along the second optical axis.

[0058] The virtual reality system according to the above-mentioned embodiments of the present application comprises three catadioptric visual lenses, which can realize light path folding and reflection by using a polarizing element, and are beneficial to the thin design of the device; the virtual reality system is matched with eight super-wide-angle positioning lenses, wherein the first lens and the second lens of the positioning lens have negative focal power, which is beneficial to increasing the field of view of the system and expanding the range of the perspective captured real picture; while increasing the wearing feeling of the user, by limiting the ratio of the sum of the effective focal lengths of the second lens and the third lens in the visual lens to the sum of the radii of curvature of the corresponding lens away from the screen side surface, the total length of the lenses can be effectively shortened, and by controlling the ratio of the medium thickness of the fifth lens and the seventh lens to the medium thickness of the sixth lens in the positioning lens, the shape and medium thickness of the rear lenses in the visual lens and the positioning lens can be controlled; and by limiting the ratio of the maximum half image height to the focal length of the positioning lens, the positioning field of view and the incident light can be as large as possible, which makes the positioning more suitable for different environmental light sources and strengthens the overall effect of the visual fusion; in addition, by controlling the ratio of the total length of the visual lens to the total length of the positioning lens, the internal space arrangement of the overall machine can be facilitated, and interference can be avoided.

[0059] In the example embodiments, the visual lens of the virtual reality system can satisfy: -1.2 < Rna / (R3a+R4a) < 1.0, wherein R3a is the radius of curvature of the first side of the second lens, R4a is the radius of curvature of the second side of the second lens, Rna is the minimum value of the radii of curvature of the first side and the second side of the first lens, and n = 1 or 2. By controlling the ratio of the radii of curvature of the two sides of the first lens to the sum of the radii of curvature of the two sides of the second lens, the shape of the first lens and the second lens can be constrained, the edge light of the positive lens can be converged, and interference during assembly can be avoided.

[0060] In the example embodiments, the visual lens of the virtual reality system can satisfy: 0.2 < f1a / V1a / CT1a < 8.0, wherein f1a is the effective focal length of the first lens, V1a is the Abbe number of the first lens, and CT1a is the center thickness of the first lens. By controlling the ratio of the effective focal length of the first lens to the Abbe number and the center thickness, the diameter of the first lens and the selection of the low dispersion coefficient material can be indirectly controlled, and the size of the lens on the human eye side can be specified.

[0061] In an example embodiment, the eyepiece lens of the virtual reality system can satisfy: -4.0 < (R4a+R5a) / (CT2a+CT3a) < -1.9, where R4a is the radius of curvature of the second side surface of the second lens, R5a is the radius of curvature of the first side surface of the third lens, CT2a is the center thickness of the second lens, and CT3a is the center thickness of the third lens. By controlling the ratio of the sum of the radii of curvature of the second lens on the screen side and the third lens on the screen side to the sum of the thicknesses of the second lens and the third lens, on the one hand, the basic forming and assembling strength can be ensured, and on the other hand, the focal length of the second lens and the third lens can be indirectly controlled to achieve screen light convergence.

[0062] In an example embodiment, the eyepiece lens of the virtual reality system can satisfy: 2.0 < (f2a / N2a) / (f3a / N3a) < 11.0, where f2a is the effective focal length of the second lens, N2a is the refractive index of the second lens, f3a is the effective focal length of the third lens, and N3a is the refractive index of the third lens. By controlling the ratio of the effective focal length to the refractive index of the second lens to the ratio of the effective focal length to the refractive index of the third lens and limiting them within a reasonable range, the material selection range can be reduced, and the application of low-stress and birefringent materials is facilitated.

[0063] In an example embodiment, the eyepiece lens of the virtual reality system can satisfy: -7.5 < R6a / R5a+R4a / R3a < 7.6, where R6a is the radius of curvature of the second side surface of the third lens, R5a is the radius of curvature of the first side surface of the third lens, R4a is the radius of curvature of the second side surface of the second lens, and R3a is the radius of curvature of the first side surface of the second lens. By controlling the ratio of the radii of curvature of the third lens on the screen side and the second lens on the screen side and limiting the sum of the two within a certain range, the shapes of the two can be constrained, the edge light convergence is facilitated, and the edge brightness of the image is improved.

[0064] In an example embodiment, the eyepiece lens of the virtual reality system can satisfy: 29mm < TDa < 40.0mm, where TDa is the distance from the second side surface of the third element group to the screen of the eyepiece lens on the first optical axis. By limiting the distance from the surface of the third lens on the screen side of the eyepiece lens to the screen, the object distance can be controlled within a reasonable range to generate a virtual image with a suitable distance, thereby enhancing the visual experience.

[0065] In the example embodiment, the visual lens of the virtual reality system can satisfy: 0.5 < CT3a / (CT1a+CT2a) < 2.5, where CT3a is the center thickness of the third lens, CT1a is the center thickness of the first lens, and CT2a is the center thickness of the second lens. By controlling the ratio of the thickness of the third lens to the thicknesses of the first lens and the second lens, on the one hand, the lens group strength is ensured, and actual processing is ensured; on the other hand, the total length of the lens group is indirectly controlled, and the space occupation in the whole device is avoided.

[0066] In the example embodiment, the positioning lens of the virtual reality system can satisfy: -0.2 < f / f1 < -0.15, where f is the total effective focal length of the positioning lens, and f1 is the effective focal length of the first lens. By controlling the ratio of the total effective focal length of the positioning lens to the effective focal length of the first lens, the focal length distribution of the first lens in the positioning lens is beneficial, and the size of the object side field of view is indirectly controlled to realize the collection of as many real scene light rays as possible, thereby achieving accurate positioning.

[0067] In the example embodiment, the positioning lens of the virtual reality system can satisfy: -13.5 < (R11+R12) / f6 < -4.3, where R11 is the curvature radius of the object side surface of the sixth lens, R12 is the curvature radius of the image side surface of the sixth lens, and f6 is the effective focal length of the sixth lens. By controlling the ratio of the sum of the curvature radii of the object side surface and the image side surface of the sixth lens to the focal length of the sixth lens, on the one hand, the lens diameter and the thickness of the sixth lens are indirectly constrained, which is beneficial for processing and forming, and on the other hand, the negative curvature design can make the light rays diverge, which is beneficial for cooperating with the front and rear positive lenses to weaken the aberration.

[0068] In the example embodiment, the positioning lens of the virtual reality system can satisfy: 3.7 < TTL / (CT5+CT7) < 4.3, where TTL is the distance from the object side surface of the first lens to the imaging surface of the positioning lens on the second optical axis, CT5 is the center thickness of the fifth lens, and CT7 is the center thickness of the seventh lens. By controlling the ratio of the distance from the object side surface of the first lens to the imaging surface of the positioning lens to the sum of the center thicknesses of the fifth lens and the seventh lens, on the one hand, the assembly and processing strength of the fifth lens and the seventh lens are ensured, and on the other hand, the total length of the positioning lens is further constrained, and the volume of the head-mounted device is compressed.

[0069] In the example embodiment, the positioning lens of the virtual reality system can satisfy: 5.8 < DT11 / CT1 / N1 < 12.5, where DT11 is the effective half aperture of the object side surface of the first lens, CT1 is the center thickness of the first lens, and N1 is the refractive index of the first lens. By controlling the ratio of the effective half aperture of the object side surface of the first lens to the center thickness and the refractive index, the focal length and the material selection of the first lens are indirectly controlled, the design range is reduced, and the processing feasibility is increased.

[0070] In the example embodiment, the positioning lens of the virtual reality system can satisfy: -2.5 < f1 / N1 / (f3 / N3) < -1.5, where f1 is the effective focal length of the first lens, N1 is the refractive index of the first lens, f3 is the effective focal length of the third lens, and N3 is the refractive index of the third lens. By controlling the ratio of the effective focal length to the refractive index of the first lens and the ratio of the effective focal length to the refractive index of the third lens of the positioning lens, the field of view size and the angle of the incident light can be adjusted, which is beneficial for the recognition of different light environments.

[0071] In the example embodiment, the positioning lens of the virtual reality system can satisfy: 2.0 < (SAG11+SAG12) / (SAG81+SAG82) < 6.0, where SAG11 is the distance between the intersection of the object side of the first lens on the second optical axis and the vertex of the maximum effective semi-aperture on the second optical axis, SAG12 is the distance between the intersection of the image side of the first lens on the second optical axis and the vertex of the maximum effective semi-aperture on the second optical axis, SAG81 is the distance between the intersection of the object side of the eighth lens on the second optical axis and the vertex of the maximum effective semi-aperture on the second optical axis, and SAG82 is the distance between the intersection of the image side of the eighth lens on the second optical axis and the vertex of the maximum effective semi-aperture on the second optical axis. By limiting the distance between the intersection of the first lens and the eighth lens on the second optical axis and the vertex of the maximum effective semi-aperture on the second optical axis, the focal length and the volume of the first lens and the eighth lens can be indirectly controlled, and the light aperture can be adjusted to avoid the reduction of RI (refractive index) caused by insufficient brightness of the edge beam, which affects the optical positioning.

[0072] In the example embodiment, the positioning lens of the virtual reality system can satisfy: -0.8 < (f5+f6) / f < 1.4, where f5 is the effective focal length of the fifth lens, f6 is the effective focal length of the sixth lens, and f is the total effective focal length of the positioning lens. By controlling the ratio of the focal length of the fifth lens and the sixth lens to the total effective focal length of the positioning lens, the focal length distribution of the fifth lens and the sixth lens and the aberration control between positive and negative lenses can be facilitated.

[0073] In the example embodiment, the positioning lens of the virtual reality system can satisfy: -0.8 < f6 / f3 (N6 / N3) < 0.2; N3 > 1.6 and N6 > 1.6; wherein, f3 is the effective focal length of the third lens, f6 is the effective focal length of the sixth lens, N3 is the refractive index of the third lens, and N6 is the refractive index of the sixth lens. The third lens and the sixth lens of the positioning lens are made of high refractive index material, and by limiting the ratio of the focal length of the sixth lens to the focal length of the third lens and the ratio of the corresponding refractive index, and controlling the product of the two within a certain range, the thickness and half aperture in the lens are indirectly controlled, the small curvature radius design is realized, the processing and assembly are ensured, the volume of the positioning lens is further compressed, and the actual demand for light weight is met.

[0074] In an example embodiment, the virtual reality system of the present application can include at least one diaphragm. The diaphragm can constrain the light path and control the light intensity. The diaphragm can be arranged at a proper position of the visual lens or the positioning lens. In an example, a first diaphragm can be included, which can be located at the first side (the human eye side) of the visual lens. In an example, a second diaphragm can also be included, which can be located between the third lens and the fourth lens of the positioning lens.

[0075] In an example embodiment, the virtual reality system of the present application can further include a protective glass for protecting the photosensitive element located on the imaging surface.

[0076] In an example embodiment, the total effective focal length fa of the visual lens can be, for example, in the range of 31.08mm to 32.31mm, and the total effective focal length f of the positioning lens can be, for example, in the range of 1.20mm to 1.56mm.

[0077] The virtual reality system according to some embodiments of the present application, by reasonably setting the curvature radius, central thickness, surface shape, refractive index and Abbe number of the lens, and the effective focal length, entrance pupil diameter and other parameters of the optical system, is conducive to improving the imaging effect and ensuring the optical performance of the system; and by reasonably setting the diaphragm, air gap of the lens, and distance between the display or the imaging surface and other parameters, it is conducive to ensuring the molding and strength of the lens, and reducing the sensitivity of the lens; at the same time, it is conducive to constraining the total length of the optical system and improving the portability of the equipment; it can also increase the field of view and improve the wearing experience of consumers.

[0078] The specific embodiments of the optical system applicable to the above embodiments will be further described below with reference to the accompanying drawings.

[0079] Example One

[0080] The following refers to Figures 2 to 3C A visual lens according to Embodiment One of the present application is described. Figure 2 A structural schematic diagram of the visual lens according to Embodiment One of the present application is shown.

[0081] AsFigure 2 As shown, the eyepiece lens comprises a first, second, and third lens group arranged in order from the eye side to the screen side along the first optical axis. The first lens group includes a first lens E1', a reflective polarizer RP, and a quarter-wave plate QWP; the second lens group includes a second lens E2'; and the third lens group includes a third lens E3'.

[0082] In this embodiment, the reflective polarizer RP and the quarter-wave plate QWP are disposed on the first side surface S3 of the first lens E1 ′ away from the screen.

[0083] In this embodiment, the eyepiece lens may further include an aperture STO, which is disposed on the human eye side of the eyepiece lens.

[0084] In this embodiment, the eyepiece lens may further include a partial reflective element BS, and the partial reflective element BS is disposed on the second side surface S6 of the second lens E2 ′ close to the screen side.

[0085] As an exemplary embodiment, image light from the screen can sequentially pass through the third lens element E3', the second lens element E2', the first lens element E1', and the quarter-wave plate QWP to reach the reflective polarizer RP. The light is then reflected by the reflective polarizer RP and passes through the quarter-wave plate QWP, the first lens element E1', and the second lens element E2' again before reaching the partially reflective element BS. The light beam is then reflected again by the partially reflective element BS and sequentially passes through the second lens element E2', the first lens element E1', the quarter-wave plate QWP, and the reflective polarizer RP to be emitted toward the eye. The eyepiece lens provided according to the embodiments of the present application uses a combination of light reflection and refraction to fold the required optical path without affecting projection quality, effectively shortening the length of the eyepiece lens body.

[0086] Table 1 shows the basic parameters of the visual lens of Example 1, where the units of curvature radius and thickness / distance are all millimeters (mm). Image light from the display screen passes through the optical surfaces of each component in sequence and is finally projected into the human eye.

[0087]

[0088] Table 1

[0089] In this embodiment, the second side surface S4 of the first lens E1', the first side surface S5 and the second side surface S6 of the second lens E2', and the first side surface S7 and the second side surface S8 of the third lens E3' are all aspherical surfaces. The surface shape of each aspherical lens is The following aspheric formulas can be used for definition, but are not limited to:

[0090] (1)

[0091] wherein, V is the distance from the vertex of the aspherical surface to a point on the aspherical surface along the optical axis at a height of h V is the distance from the vertex of the aspherical surface to a point on the aspherical surface along the optical axis at a height of c C is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above); k K is the conic constant; Ai A is the correction coefficient of the aspherical surface at the i -th order. Table 2 shows the conic constant and the high-order term coefficient A of the aspherical surfaces S4, S5, S6, S7 and S8 used in Embodiment 1. A 4 , A 6 , A 8 and A 10 .

[0092]

[0093] Table 2

[0094] Figure 3A shows the axial chromatic aberration curve of the visual lens of Embodiment 1, which represents the deviation of the converging focal points of light rays of different wavelengths after passing through the visual lens. Figure 3B shows the astigmatism curve of the visual lens of Embodiment 1, which represents the meridional image surface curvature and sagittal image surface curvature corresponding to different field angles. Figure 3C shows the distortion curve of the visual lens of Embodiment 1, which represents the distortion size values corresponding to different field angles. According to Figures 3A to 3C it can be seen that the visual lens given in Embodiment 1 can achieve good imaging quality.

[0095] Example Two

[0096] A visual lens according to Embodiment 2 of the present application is described below with reference to Figures 4 to 5C . Figure 4 shows a structural schematic diagram of the visual lens according to Embodiment 2 of the present application. In this embodiment and Embodiment 3 below, some descriptions similar to Embodiment 1 will be omitted for brevity.

[0097] As shown in Figure 4 , the visual lens sequentially comprises, along the first optical axis from the first side to the second side: a stop STO; a first element group comprising a first lens E1', a reflective polarizing element RP and a quarter-wave plate QWP; a second element group comprising a second lens E2' and a partially reflective element BS; and a third element group comprising a third lens E3'.

[0098] In this embodiment, the reflective polarizing element RP and the quarter-wave plate QWP are disposed on the second side of the first lens E1'close to the screen side. As an exemplary embodiment, the second side of the first lens E1'close to the screen side is a plane.

[0099] In this embodiment, the partially reflective element BS is disposed on the first side S5 of the second lens E2' away from the screen side.

[0100] Table 3 shows the basic parameter table of the visual lens of embodiment two, wherein the units of the radius of curvature, thickness / distance are millimeters (mm). The image light from the display screen passes through the optical surfaces of the elements in turn and is finally projected into the human eye.

[0101]

[0102] Table 3

[0103] In this embodiment, the first side S1 of the first lens E1 ', the first side S5 and the second side S6 of the second lens E2', the first side S7 and the second side S8 of the third lens E3' are all aspheric surfaces.

[0104] Table 4 shows the conic coefficients and high-order coefficients of the aspheric surfaces S1, S5, S6, S7, S8 that can be used in embodiment two A 4 , A 6 , A 8 and A 10 . Wherein each aspheric surface can be defined by the formula (1) given in the above embodiment one.

[0105]

[0106] Table 4

[0107] Figure 5A The axial chromatic aberration curve of the visual lens of embodiment two is shown, which represents the convergence focus deviation of light rays of different wavelengths after passing through the visual lens. Figure 5B The astigmatism curve of the visual lens of embodiment two is shown, which represents the meridional image surface curvature and sagittal image surface curvature corresponding to different field angles. Figure 5C The distortion curve of the visual lens of embodiment two is shown, which represents the distortion size value corresponding to different field angles. According to Figures 5A to 5C It can be seen that the visual lens given in embodiment two can achieve good imaging quality.

[0108] Example Three

[0109] The following refers to Figures 6 to 7CThe visual lens according to Embodiment Three of the present application is described. Figure 6 A structural schematic diagram of the visual lens according to Embodiment Three of the present application is shown.

[0110] As shown in Figure 6 , the visual lens comprises, in order from the first side to the second side along the first optical axis: a stop STO; a first element group comprising a reflective polarizing element RP, a quarter-wave plate QWP and a first lens E1'; a second element group comprising a second lens E2' and a partially reflective element BS; and a third element group comprising a third lens E3'.

[0111] In this embodiment, the reflective polarizing element RP and the quarter-wave plate QWP are arranged on the first side S3 of the first lens E1' on the side away from the screen. The first side S3 of the first lens E1' is a plane.

[0112] In this embodiment, the partially reflective element BS is arranged on the second side S6 of the second lens E2' on the side close to the screen.

[0113] Table 5 shows a table of basic parameters of the visual lens of Embodiment Three, wherein the units of the radius of curvature and the thickness / distance are millimeters (mm). The image light from the display screen passes through the optical surfaces of the elements in turn and is finally projected into the human eye.

[0114]

[0115] Table 5

[0116] In this embodiment, the second side S4 of the first lens E1', the first side S5 and the second side S6 of the second lens E2', and the first side S7 and the second side S8 of the third lens E3' are all aspherical surfaces.

[0117] Table 6 shows the conic coefficients and high-order term coefficients of the aspherical surfaces S4, S5, S6, S7 and S8 that can be used in Embodiment Three A 4 , A 6 , A 8 , A 10 and A 12 . Wherein each aspherical surface can be defined by the formula (1) given in Embodiment One above.

[0118]

[0119] Table 6

[0120] Figure 7AAn on-axis chromatic aberration curve of the visual lens of Embodiment Three is shown, which represents the convergence point deviation of light rays of different wavelengths after passing through the visual lens. Figure 7B A curvature of field curve of the visual lens of Embodiment Three is shown, which represents the meridional image surface curvature and sagittal image surface curvature corresponding to different field angles. Figure 7C A distortion curve of the visual lens of Embodiment Three is shown, which represents the distortion size values corresponding to different field angles. According to the distortion curve, the distortion size values of the visual lens of Embodiment Three are relatively small, and the distortion is relatively small. Figures 7A to 7C It can be seen that the visual lens given by Embodiment Three can achieve good imaging quality.

[0121] Table 7 shows some parameters of the visual lenses according to Embodiments One to Three described above, including the total effective focal length fa of the visual lens, the effective focal length f1a of the first lens, the effective focal length f2a of the second lens, and the effective focal length f3a of the third lens, all in millimeters (mm).

[0122]

[0123] Table 7

[0124] The following further describes specific embodiments of the positioning lens applicable to the above-described embodiments with reference to the accompanying drawings.

[0125] Example Four

[0126] The following further describes specific embodiments of the positioning lens applicable to the above-described embodiments with reference to the accompanying drawings. Figures 8 to 9C A positioning lens according to Embodiment Four is described.

[0127] As shown in Table 8, the positioning lens can include, in order from the object side to the image side along the second optical axis, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8. Figure 8 As an exemplary embodiment, the positioning lens can further include a stop STO, which can be disposed, for example, between the third lens E3 and the fourth lens E4, and a filter E9, which can be disposed, for example, between the image side surface S18 of the eighth lens E8 and the imaging surface S19 of the positioning lens.

[0128] In this embodiment, the first lens E1 and the second lens E2 have negative refractive powers, the third lens E3 has a positive refractive power, the fourth lens E4 has a negative refractive power, the fifth lens E5 has a positive refractive power, the sixth lens E6 has a negative refractive power, and the seventh lens E7 and the eighth lens E8 both have positive refractive powers. The filter E9 has an object side surface S17 and an image side surface S18. Light from an object passes through each of the surfaces S1 to S18 in order and is finally imaged on the imaging surface S19.

[0129]

[0130] ​Table 8 shows a basic parameter table of the positioning lens of Example Four, wherein the units of the radius of curvature, thickness / distance are millimeters (mm).

[0131]

[0132] Table 8

[0133] In this example, the object side and the image side of any one of the second lens E2 to the eighth lens E8 are aspherical surfaces, and the surface type of each aspherical lens is which can be defined by, but not limited to, the formula (1) given in Example One. Table 9 shows the high order term coefficients of the aspherical surfaces S3-S16 that can be used in the positioning lens of Example Four A 4 , A 6 , A 8 , A 10 , A 12 , A 14 and A 16 .

[0134]

[0135] Table 9

[0136] Figure 9A shows the axial chromatic aberration curve of the positioning lens of Example Four, which represents the deviation of the converging focus points of light rays of different wavelengths after passing through the positioning lens. Figure 9B shows the astigmatism curve of the positioning lens of Example Four, which represents the meridional image surface curvature and sagittal image surface curvature corresponding to different field angles. Figure 9C shows the magnification chromatic aberration curve of the positioning lens of Example Four, which represents the deviation of the image height on the imaging surface after the light rays pass through the positioning lens. According to Figures 9A to 9C It can be seen that the positioning lens given in Example Four can achieve good imaging quality.

[0137] Example Five

[0138] According to Example Five of the present application, a positioning lens is described below with reference to Figures 10 to 11C In this example and the following examples, for the sake of brevity, some similar descriptions as Example Four will be omitted.

[0139] As Figure 10As shown, the positioning lens can include, in order from the object side to the image side along the second optical axis, a first lens E1, a second lens E2, a third lens E3, a stop STO, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8.

[0140] In this embodiment, the first lens E1 and the second lens E2 have negative refractive powers, the third lens E3 has a positive refractive power, the fourth lens E4 has a positive refractive power, the fifth lens E5 has a positive refractive power, the sixth lens E6 has a negative refractive power, and the seventh lens E7 and the eighth lens E8 have positive refractive powers.

[0141] Table 10 shows a basic parameter table of the positioning lens of Embodiment Five, wherein the units of the radius of curvature, the thickness / distance are all millimeters (mm).

[0142]

[0143] Table 10

[0144] In this embodiment, the object side surface and the image side surface of any one of the second lens E2 to the eighth lens E8 are aspherical surfaces, and the surface type of each aspherical lens may be defined by, but not limited to, the formula (1) given in Embodiment One. Tables 11-1 and 11-2 show the high-order term coefficients of the aspherical surfaces S3-S16 that can be used in the positioning lens of Embodiment Five. A 4 , A 6 , A 8 , A 10 , A 12 , A 14 , A 16 and A 18 , A 20 , A 22 , A 24 , A 26 , A 28 and A 30 .

[0145]

[0146] Table 11-1

[0147]

[0148] Table 11-2

[0149] Figure 11A The axial chromatic aberration curve of the positioning lens of embodiment five is shown, which represents the convergence point deviation of light rays of different wavelengths after passing through the positioning lens. Figure 11B The astigmatic curve of the positioning lens of embodiment five is shown, which represents the meridional image surface curvature and sagittal image surface curvature corresponding to different field angles. Figure 11C The magnification chromatic aberration curve of the positioning lens of embodiment five is shown, which represents the deviation of light rays on the imaging surface after passing through the positioning lens at different image heights. According to the formula Figures 11A to 11C It can be seen that the positioning lens given by embodiment five can achieve good imaging quality.

[0150] Example Six

[0151] The following refers to Figures 12 to 13C The positioning lens according to embodiment six of the present application is described.

[0152] As Figure 12 shown, the positioning lens can include, in order from the object side to the image side along the second optical axis, a first lens E1, a second lens E2, a third lens E3, a stop STO, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8.

[0153] In this embodiment, the first lens E1 and the second lens E2 have negative focal power, the third lens E3 has positive focal power, the fourth lens E4 has positive focal power, the fifth lens E5 has positive focal power, the sixth lens E6 has negative focal power, and the seventh lens E7 and the eighth lens E8 have positive focal power.

[0154] Table 12 shows the basic parameter table of the positioning lens of embodiment six, wherein the units of the curvature radius, thickness / distance are millimeters (mm).

[0155]

[0156] Table 12

[0157] In this embodiment, the object side surface and the image side surface of any one of the second lens E2 to the eighth lens E8 are aspherical surfaces, and the surface type of each aspherical lens can be defined using, but not limited to, the formula (1) given in embodiment one. Tables 13-1 and 13-2 show the high-order term coefficients of the aspherical surfaces S3-S16 that can be used in the positioning lens of embodiment six. A 4 、 A 6 、 A 8 ​、 A 10 、 A 12 、 A 14 、 A 16 and A 18 、 A 20 、 A 22 、 A 24 、 A 26 、 A 28 and A 30 .

[0158]

[0159] Table 13-1

[0160]

[0161] Table 13-2

[0162] Figure 13A A curve of axial chromatic aberration of the positioning lens of Embodiment Six is shown, which represents the deviation of convergent focal points of light rays of different wavelengths after passing through the positioning lens. Figure 13B A curve of astigmatism of the positioning lens of Embodiment Six is shown, which represents the meridional image surface curvature and sagittal image surface curvature corresponding to different field angles. Figure 13C A curve of magnification chromatic aberration of the positioning lens of Embodiment Six is shown, which represents the deviation of different image heights of light rays on the imaging plane after passing through the positioning lens. According to Figures 13A to 13C It can be known that the positioning lens given by Embodiment Six can achieve good imaging quality.

[0163] Example Seven

[0164] According to Embodiment Seven of the present application, a positioning lens is described below with reference to Figures 14 to 15C .

[0165] As shown in Figure 14 , the positioning lens can include, in order from the object side to the image side along the second optical axis, a first lens E1, a second lens E2, a third lens E3, a stop STO, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8.

[0166] In this embodiment, the first lens E1 and the second lens E2 have negative focal power, the third lens E3 has positive focal power, the fourth lens E4 has positive focal power, the fifth lens E5 has positive focal power, the sixth lens E6 has negative focal power, and the seventh lens E7 and the eighth lens E8 have positive focal power.

[0167] Table 14 shows a basic parameter table of the positioning lens of Example Seven, wherein the units of the radius of curvature, thickness / distance are millimeters (mm).

[0168]

[0169] Table 14

[0170] In this embodiment, the object side and the image side of any one of the second lens E2 to the eighth lens E8 are aspherical surfaces, and the surface type of each aspherical lens is may be defined by, but not limited to, the formula (1) given in Example One. Tables 15-1 and 15-2 show the high-order term coefficients of the aspherical surfaces S3-S16 that can be used in the positioning lens of Example Seven. A 4 , A 6 , A 8 , A 10 , A 12 , A 14 , A 16 and A 18 , A 20 , A 22 , A 24 , A 26 , A 28 and A 30 .

[0171]

[0172] Table 15-1

[0173]

[0174] Table 15-2

[0175] Figure 15A The on-axis chromatic aberration curve of the positioning lens of Example Seven is shown, which represents the convergence focus deviation of light rays of different wavelengths after passing through the positioning lens.Figure 15B The astigmatic curve of the positioning lens of embodiment seven is shown, which represents the meridional image surface curvature and sagittal image surface curvature corresponding to different field angles. Figure 15C The magnification chromatic aberration curve of the positioning lens of embodiment seven is shown, which represents the deviation of light rays on the imaging surface at different image heights after passing through the positioning lens. According to the formula Figures 15A to 15C It can be seen that the positioning lens given by embodiment seven can achieve good imaging quality.

[0176] Table 16 below shows the basic parameter data of the positioning lenses according to the above embodiments four to seven of the present application, wherein the units of focal length, height and distance are all millimeters (mm).

[0177]

[0178] Table 16

[0179] In summary, according to the virtual reality system provided by the above embodiments one to seven of the present application, the visual lens satisfies the condition formula in Table 17, and the positioning lens satisfies the condition formula in Table 18.

[0180]

[0181] Table 17

[0182]

[0183] Table 18

[0184] According to the virtual reality system of the present application, the system total length of the visual lens and the positioning lens satisfies the condition formula 2.2 < TTLa / TTL < 4.7, as shown in Table 19. In the table, TTLa1-TTLa3 are the axial distances from the surface of the first lens of the visual lens in embodiments one to three to the screen, and TTL4-TTL7 are the axial distances from the object side surface of the first lens of the positioning lens in embodiments four to seven to the imaging surface.

[0185]

[0186] Table 19

[0187] The above description is merely preferred embodiments of the present application and a description of the principles of the technology used. It should be understood by those skilled in the art that the scope of the application disclosed in the present application is not limited to the technical solutions formed by the specific combinations of the above technical features, and also covers other technical solutions formed by any combination of the above technical features or equivalent features without departing from the inventive concept. For example, the above features are replaced with the technical features disclosed in the present application (but not limited to) having similar functions to form technical solutions.

Claims

1. A virtual reality system, characterized in that: Including visual lens and positioning lens, among which, The eyepiece lens includes, in sequence from a first side away from the screen to a second side close to the screen along the first optical axis: A first element group includes a reflective polarizing element, a quarter-wave plate, and a first lens with positive optical power, wherein the first side surface or the second side surface of the first lens is a plane; a second element group including a second lens having positive optical power; and a third element group including a third lens element having positive optical power; The positioning lens includes, in order from the object side to the image side along the second optical axis, a first lens with negative optical power, a second lens with negative optical power, a third lens with positive optical power, a fourth lens with optical power, a fifth lens with positive optical power, a sixth lens with negative optical power, a seventh lens with positive optical power, and an eighth lens with positive optical power; The number of lenses having optical power in the eyepiece lens is three; The number of lenses having optical power in the positioning lens is eight; The positioning lens is used to form an image of a real scene, and the formed real image is transmitted to the screen in the form of an electrical signal; The virtual reality system satisfies: -10.89≤(f2a+f3a) / (R3a+R5a)≤0.15; -3.88≤(R4a+R5a) / (CT2a+CT3a)≤-2.13; 11.52≤(CT5+CT7) / CT6≤13.15; 1.89 ≤ ImgH / f ≤ 1.92; and 2.32≤TTLa / TTL≤4.55; Among them, f2a is the effective focal length of the second lens, f3a is the effective focal length of the third lens, R3a is the curvature radius of the first side of the second lens, R4a is the curvature radius of the second side of the second lens, R5a is the curvature radius of the first side of the third lens, CT2a is the center thickness of the second lens, CT3a is the center thickness of the third lens, CT5 is the center thickness of the fifth lens, CT7 is the center thickness of the seventh lens, CT6 is the center thickness of the sixth lens, ImgH is half of the image height corresponding to the maximum field of view angle of the positioning lens, f is the total effective focal length of the positioning lens, TTLa is the distance from the first side of the first element group to the screen of the eyepiece lens on the first optical axis, and TTL is the distance from the object side of the first lens to the imaging surface of the positioning lens on the second optical axis.

2. The virtual reality system according to claim 1, wherein: The visual lens meets the following requirements: -1.05≤Rna / (R3a+R4a)≤0.6, Wherein, R3a is the curvature radius of the first side surface of the second lens, R4a is the curvature radius of the second side surface of the second lens, Rna is the minimum value of the curvature radius of the first side surface and the second side surface of the first lens, and n=1 or 2.

3. The virtual reality system according to claim 1, wherein: The visual lens meets the following requirements: 0.5≤f1a / V1a / CT1a≤7.88, Wherein, f1a is the effective focal length of the first lens, V1a is the Abbe number of the first lens, and CT1a is the center thickness of the first lens.

4. The virtual reality system according to claim 1, wherein: The visual lens meets the following requirements: 2.45≤(f2a / N2a) / (f3a / N3a)≤10.8, Among them, f2a is the effective focal length of the second lens, N2a is the refractive index of the second lens, f3a is the effective focal length of the third lens, and N3a is the refractive index of the third lens.

5. The virtual reality system according to claim 1, wherein: The visual lens meets the following requirements: -7.04≤R6a / R5a+R4a / R3a≤7.49, Among them, R6a is the curvature radius of the second side of the third lens, R5a is the curvature radius of the first side of the third lens, R4a is the curvature radius of the second side of the second lens, and R3a is the curvature radius of the first side of the second lens.

6. The virtual reality system according to claim 1, wherein: The visual lens meets the following requirements: 0.97≤CT3a / (CT1a+CT2a)≤2.18, Wherein, CT3a is the center thickness of the third lens, CT1a is the center thickness of the first lens, and CT2a is the center thickness of the second lens.

7. The virtual reality system according to claim 1, wherein: The positioning lens satisfies: -0.2 <f / f1<-0.15, Wherein, f is the total effective focal length of the positioning lens, and f1 is the effective focal length of the first lens.

8. The virtual reality system according to claim 1, wherein: The positioning lens satisfies: -13.43≤(R11+R12) / f6≤-4.55, Wherein, R11 is the curvature radius of the object-side surface of the sixth lens, R12 is the curvature radius of the image-side surface of the sixth lens, and f6 is the effective focal length of the sixth lens.

9. The virtual reality system according to any one of claims 1 to 8, wherein: The positioning lens satisfies: 3.94≤TTL / (CT5+CT7)≤4.12, Wherein, TTL is the distance from the object side surface of the first lens to the imaging surface of the positioning lens on the second optical axis, CT5 is the center thickness of the fifth lens, and CT7 is the center thickness of the seventh lens.

10. The virtual reality system according to any one of claims 1 to 8, wherein: The positioning lens satisfies: 6.1≤DT11 / CT1 / N1≤11.21, Wherein, DT11 is the effective semi-aperture of the object-side surface of the first lens, CT1 is the center thickness of the first lens, and N1 is the refractive index of the first lens.

11. The virtual reality system according to any one of claims 1 to 8, wherein: The positioning lens satisfies: -2.18≤f1 / N1 / (f3 / N3)≤-1.65, Wherein, f1 is the effective focal length of the first lens, N1 is the refractive index of the first lens, f3 is the effective focal length of the third lens, and N3 is the refractive index of the third lens.

12. The virtual reality system according to any one of claims 1 to 8, wherein: The positioning lens satisfies: 2.09≤(SAG11+SAG12) / (SAG81+SAG82)≤5.89, Among them, SAG11 is the distance between the intersection of the object side of the first lens on the second optical axis and the object side maximum effective half-aperture vertex of the first lens on the second optical axis, SAG12 is the distance between the intersection of the image side of the first lens on the second optical axis and the image side maximum effective half-aperture vertex of the first lens on the second optical axis, SAG81 is the distance between the intersection of the object side of the eighth lens on the second optical axis and the object side maximum effective half-aperture vertex of the eighth lens on the second optical axis, and SAG82 is the distance between the intersection of the image side of the eighth lens on the second optical axis and the image side maximum effective half-aperture vertex of the eighth lens on the second optical axis.

13. The virtual reality system according to any one of claims 1 to 8, wherein: The positioning lens satisfies: -0.69≤(f5+f6) / f≤1.2, Among them, f5 is the effective focal length of the fifth lens, f6 is the effective focal length of the sixth lens, and f is the total effective focal length of the positioning lens.

14. The virtual reality system according to any one of claims 1 to 8, wherein: The positioning lens satisfies: -0.63≤f6 / f3 (N6 / N3)≤-0.46; 1.671≤N3≤1.76 and 1.671≤N6≤1.75; Wherein, f3 is the effective focal length of the third lens, f6 is the effective focal length of the sixth lens, N3 is the refractive index of the third lens, and N6 is the refractive index of the sixth lens.

15. The virtual reality system according to claim 1, wherein: The second side surface of the second lens is a convex surface; The first side surface of the third lens is a convex surface; The object side surface of the first lens is convex, and the image side surface is concave; The object side surface of the second lens is concave, and the image side surface is concave; The object side surface of the third lens is convex, and the image side surface is concave; The object-side surface of the fourth lens is concave, and the image-side surface is convex; The object-side surface of the fifth lens is convex, and the image-side surface is convex; The object-side surface of the sixth lens is concave, and the image-side surface is concave; The object-side surface of the seventh lens is convex, and the image-side surface is convex; The object-side surface of the eighth lens is convex, and the image-side surface is concave.

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