Virtual reality system

Abstract

A virtual reality system includes first and second optical systems, the first optical system sequentially includes first to fourth element groups from a first side to a second side along a first optical axis, the first element group includes a first lens, a reflective polarizing element and a first quarter wave plate; the second element group includes a second lens and a second quarter wave plate; the third and fourth element groups respectively include a third and fourth lens; the second optical system sequentially includes first to fifth lenses from an object side to an image side along a second optical axis. An on-axis distance TD' from a first side surface of the first element group to a second side surface of the fourth lens, an effective focal length f' of the first optical system, an on-axis distance TD from an object side surface of the first lens to an image side surface of the fifth lens, and an effective focal length f of the second optical system satisfy TD' / f'<1.3, 5.0<TD / f<8.0 and TD' / TD<3.0.

Description

Technical Field

[0001] This application relates to the field of optical devices, and particularly to a virtual reality system. Background Art

[0002] With the development of virtual reality technology, more and more lenses are applied to various devices of virtual reality technology, including, for example, eyepieces providing immersion, perspective lenses for interacting with reality, positioning lenses for capturing movements, facial recognition lenses for constructing expressions, etc.

[0003] In order to enhance immersion and improve user experience, different virtual reality devices are configured with different types of lenses. Therefore, how to achieve a better experience of the virtual reality system and a smaller proportion of the optical system has become one of the main design goals of the current virtual reality system. Summary of the Invention

[0004] This application provides a virtual reality system that can at least solve or partially solve at least one problem or other problems existing in the prior art.

[0005] This application provides a virtual reality system, which may include a first optical system and a second optical system. The first optical system may sequentially include a first element group, a second element group, a third element group, and a fourth element group along a first optical axis from a first side to a second side. Among them, the first element group may include a first lens, a reflective polarizing element, and a first quarter-wave plate; the second element group may include a second lens and a second quarter-wave plate; the third element group may include a third lens; the fourth element group may include a fourth lens; the second optical system may sequentially include a first lens, a second lens, a third lens, a fourth lens, and a fifth lens along a second optical axis from an object side to an image side; wherein, the real image formed by the second optical system can be transmitted to the first optical system in the form of an electrical signal, the first optical system can be used to project a virtual reality image and the real image on an image plane disposed on the second side, and the axial distance TD' from the first side of the first element group to the second side of the fourth lens and the effective focal length f' of the first optical system satisfy: TD' / f'<1.3, the axial distance TD from the object side of the first lens to the image side of the fifth lens and the effective focal length f of the second optical system satisfy: 5.0<TD / f<8.0, and the axial distance TD' from the first side of the first element group to the second side of the fourth lens and the axial distance TD from the object side of the first lens to the image side of the fifth lens satisfy: TD' / TD<3.0.

[0006] According to an exemplary embodiment of the present application, the effective focal length f' of the first optical system and the effective focal length f of the second optical system satisfy: 8.0<f' / f<15.0.

[0007] According to an exemplary embodiment of the present application, the effective focal length f1 of the first lens and the combined focal length f45 of the fourth lens and the fifth lens may satisfy: |(f1 + f45)| / f' < 1.0.

[0008] According to an exemplary embodiment of the present application, the maximum field angle FOV of the second optical system and the maximum field angle FOV' of the first optical system may satisfy: 1.3 < FOV / FOV' < 1.8.

[0009] According to an exemplary embodiment of the present application, the effective focal length f4' of the fourth lens may satisfy: 1.0 < f4' / f' < 2.0, and the on-axis distance TTL from the object side surface of the first lens to the imaging surface of the second optical system may satisfy: 7.0 < TTL / f < 9.5.

[0010] According to an exemplary embodiment of the present application, the effective focal length f1' of the first element group, the dispersion coefficient V1' of the first lens, the dispersion coefficient VR of the reflective polarizing element, the dispersion coefficient VQ1 of the first quarter-wave plate, the effective focal length f2' of the second element group, the dispersion coefficient V2' of the second lens, the dispersion coefficient VQ2 of the second quarter-wave plate, the central thickness CT1' of the first element group on the first optical axis, and the central thickness CT2' of the second element group on the first optical axis may satisfy: 15.0 < [f1' / (V1' + VR + VQ1) + f2' / (V2' + VQ2)] / (CT1' + CT2') < 21.0.

[0011] According to an exemplary embodiment of the present application, the effective focal length f3' of the third lens and the effective focal length f4' of the fourth lens may satisfy: 0 < (f3' + f4') / (f3' - f4') < 2.0.

[0012] According to an exemplary embodiment of the present application, the curvature radius R2' of the second side surface of the first lens, the curvature radius R6' of the second side surface of the third lens, the air gap T12' between the first element group and the second element group on the first optical axis, the dispersion coefficient V2' of the second lens, the air gap T23' between the second element group and the third element group on the first optical axis, and the dispersion coefficient V3' of the third lens may satisfy: -11.0 < (R2' + R6') / (T12' × V2' + T23' × V3') < -7.0.

[0013] According to an exemplary embodiment of this application, the radius of curvature R7' of the first side surface of the fourth lens, the radius of curvature R8' of the second side surface of the fourth lens, and the effective focal length f4' of the fourth lens can satisfy: -7.5 < (R7'-R8') / (f'-f4') < -6.0.

[0014] According to an exemplary embodiment of this application, the distance T01 from the first side of the first element group to the entrance pupil position of the first optical system on the first optical axis can satisfy: 1.0 <f' / T01<1.5。

[0015] According to an exemplary embodiment of this application, the radius of curvature R2' of the second side surface of the first lens can satisfy: -0.5 <f' / R2'<0。

[0016] According to an exemplary embodiment of this application, the refractive index N1' of the first lens, the refractive index N2' of the second lens, the radius of curvature R2' of the second side surface of the first lens, the refractive index N3' of the third lens, and the radius of curvature R6' of the second side surface of the third lens can satisfy: 11.0mm < (N1'-N2')×R2'-(N2'-N3')×R6' < 16.0mm.

[0017] According to an exemplary embodiment of this application, the fourth lens and the fifth lens are cemented together to form a cemented lens, and the combined focal length f45 of the fourth lens and the fifth lens satisfies: 0 <f / f45<0.6。

[0018] According to an exemplary embodiment of this application, the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, the refractive index N1 of the first lens, the refractive index N2 of the second lens, and the air gap T12 between the first lens and the second lens on the second optical axis can satisfy: 14.0 < (f1 + f2) × (N1 + N2) / T12 < 19.0.

[0019] According to an exemplary embodiment of this application, the axial distance SD from the aperture of the second optical system to the image-side surface of the fifth lens can satisfy half the diagonal length ImgH of the effective pixel area on the imaging plane of the second optical system: 1.1 <SD / ImgH<1.6。

[0020] According to an exemplary embodiment of this application, the radius of curvature R1 of the object side of the first lens, the radius of curvature R2 of the image side of the first lens, and the radius of curvature R10 of the image side of the fifth lens can satisfy: -3.6<(R1+R2) / R10<-0.5.

[0021] According to an exemplary embodiment of this application, the center thickness CT4 of the fourth lens on the second optical axis, the center thickness CT5 of the fifth lens on the second optical axis, the radius of curvature R8 of the image side surface of the fourth lens, and the radius of curvature R10 of the image side surface of the fifth lens can satisfy: -1.0<(CT4+CT5) / (R8+R10)<0.

[0022] According to an exemplary embodiment of this application, the dispersion coefficient V1 of the first lens, the dispersion coefficient V2 of the second lens, the center thickness CT1 of the first lens on the second optical axis, the center thickness CT2 of the second lens on the second optical axis, and the effective focal length f1 of the first lens can satisfy: -35.0 < (V1 + V2) × (CT1 + CT2) / f1 < -20.0.

[0023] According to an exemplary embodiment of this application, the dispersion coefficient V2 of the second lens, the dispersion coefficient V3 of the third lens, the air gap T23 between the second lens and the third lens on the second optical axis, the center thickness CT2 of the second lens on the second optical axis, and the center thickness CT3 of the third lens on the second optical axis can satisfy: (|V2-V3|×T23) / [(V2+V3)×(CT2+CT3)]<1.0.

[0024] According to an exemplary embodiment of this application, the first element group has positive optical power; the second element group has negative optical power; the third lens has positive optical power; and the fourth lens has positive optical power.

[0025] The virtual reality system provided in this application is configured as a combination of a first optical system and a second optical system. The first optical system, for example, can be located within the screen and is responsible for transmitting the image from the screen to the user's eyes, providing a sense of virtual immersion. The second optical system, for example, can collect positional data from components such as controllers and transmit it via a chip to the screen of the first optical system, helping the user determine the position of their hands on the screen. The combination of the virtual immersion provided by the first optical system and the positioning function of the second optical system can overcome the spatial limitations of virtual reality, enabling interaction between the virtual device and the real world. By configuring the second optical system with five lenses, a smaller focal length within a given effective image plane can be achieved, resulting in a larger field of view, which helps the system more easily capture the position and orientation of the controllers. By controlling the ratio of the on-axis distance from the first side of the first lens to the second side of the last lens in the first optical system to the focal length of the first system, and by controlling the ratio of the on-axis distance from the object side of the first lens to the image side of the last lens in the second optical system to the focal length of the system, the structural compactness of the first and second optical systems can be maximized while ensuring good imaging quality. At the same time, by reasonably controlling the on-axis distance from the first lens (or lens) to the last lens (or lens) in the two systems, the two optical systems can be made to account for a smaller proportion of the entire virtual reality system. Attached Figure Description

[0026] Other features, objects, and advantages of this application will become more apparent from the following detailed description of the embodiments, taken in conjunction with the accompanying drawings. In the drawings:

[0027] Figure 1 A schematic plan view of a virtual reality system according to this application is shown;

[0028] Figure 2 A schematic diagram of the structure of a first optical system according to an exemplary embodiment of this application and a schematic diagram of the deflection of a portion of light rays through the first optical system are shown.

[0029] Figure 3 A schematic diagram of the structure of the first optical system according to Embodiment 1 of this application is shown;

[0030] Figure 4 , Figure 5 and Figure 6 The on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the first optical system according to Embodiment 1 of this application are shown respectively.

[0031] Figure 7 A schematic diagram of the structure of the first optical system according to Embodiment 2 of this application is shown;

[0032] Figure 8 , Figure 9 and Figure 10The on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the first optical system according to Embodiment 2 of this application are shown respectively.

[0033] Figure 11 A schematic diagram of the structure of the first optical system according to Embodiment 3 of this application is shown;

[0034] Figure 12 , Figure 13 and Figure 14 The on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the first optical system according to Embodiment 3 of this application are shown respectively.

[0035] Figure 15 A schematic diagram of the structure of the second optical system according to Embodiment 4 of this application is shown;

[0036] Figure 16 , Figure 17 and Figure 18 The on-axis chromatic aberration curve, astigmatism curve, and f-θ distortion curve of the second optical system according to Embodiment 4 of this application are shown respectively.

[0037] Figure 19 A schematic diagram of the structure of the second optical system according to Embodiment 5 of this application is shown;

[0038] Figure 20 , Figure 21 and Figure 22 The on-axis chromatic aberration curve, astigmatism curve, and f-θ distortion curve of the second optical system according to Embodiment 5 of this application are shown respectively.

[0039] Figure 23 A schematic diagram of the structure of the second optical system according to Embodiment Six of this application is shown;

[0040] Figure 24 , Figure 25 and Figure 26 The on-axis chromatic aberration curve, astigmatism curve, and f-θ distortion curve of the second optical system according to Embodiment Six of this application are shown respectively.

[0041] Figure 27 A schematic diagram of the structure of the second optical system according to Embodiment 7 of this application is shown; and

[0042] Figure 28 , Figure 29 and Figure 30 The on-axis chromatic aberration curve, astigmatism curve, and f-θ distortion curve of the second optical system according to Embodiment 7 of this application are shown respectively. Detailed Implementation

[0043] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements.

[0044] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of this application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0045] In the accompanying drawings, for ease of illustration, the thickness, size, and shape of the lenses and / or mirrors have been slightly exaggerated. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not drawn strictly to scale.

[0046] In this text, the paraxial region refers to the region near the optical axis. If the lens and / or lens surface is convex and the location of the convexity is not defined, it means that the lens and / or lens surface is convex at least in the paraxial region; if the lens and / or lens surface is concave and the location of the concaveness is not defined, it means that the lens and / or lens surface is concave at least in the paraxial region. The surface of each lens closest to the first side (e.g., the human eye side) is called the first side surface of the lens, and the surface of each lens closest to the second side (e.g., the display screen side) is called the second side surface of the lens. The surface of each lens closest to the object being photographed is called the object side surface of the lens, and the surface of each lens closest to the imaging plane is called the image side surface of the lens.

[0047] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising" as used in this specification indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0048] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formalized sense, unless expressly so specified herein.

[0049] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0050] The features, principles and other aspects of this application are described in detail below.

[0051] refer to Figure 1 The first aspect of this application provides a virtual reality system that may include a first optical system and a second optical system. The second optical system is used to image a real scene, and the formed real image is transmitted to the first optical system in the form of an electrical signal. The first optical system can be used to project a virtual reality image and the aforementioned real image onto an image surface disposed on a second side. By combining the first and second optical systems, virtual reality fusion of the virtual reality system can be achieved. The first optical system may be configured as a catadioptric optical system, and the number of such systems may be one or more. The second optical system may be configured as a transmissive optical system, and the number of such systems may be one or more. In one example, the virtual reality system may include two symmetrically arranged first optical systems. In one example, the virtual reality system also includes a body, the first optical system may be disposed on the inner side of the body, and the second optical system may be disposed on the outer side of the body.

[0052] In an exemplary embodiment, the first optical system may include a first element group, a second element group, a third element group, and a fourth element group arranged sequentially along a first optical axis from a first side to a second side. The first element group may include a first lens, a reflective polarizing element, and a first quarter-wave plate. The second element group may include a second lens and a second quarter-wave plate. The third element group may include a third lens. The fourth element group may include a fourth lens.

[0053] In an exemplary embodiment, the first side can be the human eye side, and the second side can be the display screen side. Accordingly, the first side of each element such as the first lens, second lens, third lens, fourth lens, reflective polarizing element, first quarter-wave plate, and second quarter-wave plate can be referred to as the side near the human eye, and the second side can be referred to as the side near the screen.

[0054] In an exemplary embodiment, the first optical system may further include a partially reflective layer, which may be attached, for example, to the second side surface of the first lens. The partially reflective layer has a semi-transmissive and semi-reflective effect on light. By providing a partially reflective layer, for example, on the second side surface of the first lens, and combining it with reflective polarizing elements and quarter-wave plates, light can be refracted multiple times, effectively reducing the overall length of the first optical system.

[0055] In an exemplary embodiment, the first optical system may further include an aperture stop, which may be disposed, for example, between the first side and the first element group. The image light on the display screen is finally projected to the user's eyes after multiple refractions and reflections through the fourth lens, the third lens, the second lens, the second quarter-wave plate, the first lens, the first quarter-wave plate, and the reflective polarizing element.

[0056] In an exemplary embodiment, a display screen is disposed on the image surface of the second side of the first optical system. Image light from the display screen sequentially passes through a fourth lens, a third lens, a second lens, a second quarter-wave plate, a first lens, and a first quarter-wave plate, reaching a reflective polarizing element, where it is reflected to form a first reflected image light. The first reflected image light then sequentially passes through the first quarter-wave plate and the first lens, reaching a partial reflective layer, where it is reflected to form a second reflected image light. The second reflected image light then sequentially passes through the first lens, the first quarter-wave plate, and the reflective polarizing element to the aperture stop and is finally projected into the user's eye. In other examples, the order in which the image light, the first reflected image light, and the second reflected image light pass through the elements can be adjusted as needed. The first optical system provided in this application effectively shortens the overall length of the first optical system by folding the required optical path through a combination of light reflection and refraction without affecting the projection quality.

[0057] In an exemplary embodiment, the second optical system may include a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged sequentially along the second optical axis from the object side to the image side.

[0058] In an exemplary embodiment, the first lens may have negative optical power. The second lens may have negative optical power. The third lens may have positive optical power. The fourth lens may have either positive or negative optical power. The fifth lens may have either positive or negative optical power. In an exemplary embodiment, the fourth and fifth lenses may have optical powers with opposite properties.

[0059] In an exemplary embodiment, the fourth and fifth lenses can be cemented together to form a cemented doublet lens.

[0060] The first optical system in this application is used to transmit the virtual image of the display screen (such as including virtual reality images) to the user's eyes, which can give consumers a virtual immersion feeling. The second optical system is used to image real scenes. For example, it can be responsible for collecting the position data of the handle, etc., and transmit the formed real image to the display screen of the first optical system through the chip of the second optical system. Then the first optical system transmits the real image on the display screen to the user. For example, it can help the user judge the position of their own hands in the screen. The virtual immersion feeling of the first optical system combined with the positioning function of the second optical system can break through the space limitation of virtual reality, realize the interaction between the virtual device in the real world and the virtual world, enable the user to view the image after the fusion of the virtual picture and the real scene, and improve the visual immersion feeling of the virtual reality system. By setting the second optical system to include five lenses, it can meet the requirement of having a smaller focal length under a certain effective image plane, thus having a larger field angle, which can help the system capture the position and direction of the handle more conveniently.

[0061] In an exemplary embodiment, the distance TD' on the first optical axis from the first side of the first element group in the first optical system to the second side of the fourth lens and the effective focal length f' of the first optical system may satisfy: TD' / f'<1.3. By controlling this conditional expression, the structural compactness of the first optical system can be improved as much as possible and its good imaging quality can be ensured at the same time.

[0062] In an exemplary embodiment, the distance TD on the second optical axis from the object side of the first lens in the second optical system to the image side of the fifth lens and the effective focal length f of the second optical system may satisfy: 5.0<TD / f<8.0. By controlling this conditional expression, the structural compactness of the second optical system can be improved as much as possible and its good imaging quality can be ensured at the same time.

[0063] In an exemplary embodiment, the distance TD' on the first optical axis from the first side of the first element group in the first optical system to the second side of the fourth lens and the distance TD on the second optical axis from the object side of the first lens in the second optical system to the image side of the fifth lens may satisfy: TD' / TD<3.0. By controlling this conditional expression, a smaller proportion of the first optical system and the second optical system in the entire virtual reality system can be achieved. More specifically, TD' and TD may satisfy: 2.0<TD' / TD<2.4.

[0064] The virtual reality system according to an exemplary embodiment of the present application can be configured in a structural form that combines a first optical system and a second optical system. The first optical system, for example, can be disposed inside and is responsible for transmitting the image of the screen to the human eye, giving consumers a virtual immersion feeling. The second optical system, for example, can be responsible for collecting the position data of the handle and the like, and transmitting it to the screen of the first optical system through a chip to help the user judge the position of their hands in the screen. The virtual immersion feeling of the first optical system combined with the positioning function of the second optical system can break through the spatial limitations of virtual reality and realize the interaction between the virtual device in the real world and the virtual world. By setting the second optical system to include five lenses, it can meet the requirement of having a smaller focal length under a certain effective image plane, thereby having a larger field of view angle, which can help the system capture the position and direction of the handle more conveniently. By controlling the ratio of the axial distance from the first side of the first lens to the second side of the last lens in the first optical system to the focal length of the first system, and controlling the ratio of the axial distance from the object side of the first lens to the image side of the last lens in the second optical system to the system focal length, the structural compactness of the first optical system and the second optical system can be improved as much as possible and good imaging quality can be ensured. At the same time, by reasonably controlling the axial distance from the first lens (or lens) to the last lens (or lens) in the two systems, a smaller proportion of the two optical systems in the entire virtual reality system can be achieved.

[0065] In an exemplary embodiment, the effective focal length f' of the first optical system and the effective focal length f of the second optical system can satisfy: 8.0 < f' / f < 15.0. By controlling this conditional expression, it helps to ensure the combination of the performance of the first optical system and the second optical system. It helps to control the second optical system to have a smaller focal length, which is beneficial for the second optical system to have a smaller image plane and a larger field of view angle to receive ambient light, so as to locate the position of the handle, which is beneficial for the imaging of the second optical system.

[0066] In an exemplary embodiment, the effective focal length f1 of the first lens in the second optical system, the combined focal length f45 of the fourth and fifth lenses, and the effective focal length f' of the first optical system can satisfy: |(f1 + f45)| / f' < 1.0. By controlling this conditional expression, the refractive power and optical power of the first and second optical systems can be reasonably balanced.

[0067] In an exemplary embodiment, the maximum field of view angle FOV of the second optical system and the maximum field of view angle FOV' of the first optical system can satisfy: 1.3 < FOV / FOV' < 1.8. By controlling this conditional expression, it can be ensured to the greatest extent that the environmental field of view collected by the second optical system is large enough, and it can be ensured that the handle can be detected within the maximum limit, thereby giving the user sufficient feedback.

[0068] In an exemplary embodiment, the effective focal length f4' of the fourth lens in the first optical system and the effective focal length f' of the first optical system may satisfy: 1.0 < f4' / f' < 2.0. The on-axis distance TTL from the object side surface of the first lens in the second optical system to the imaging surface of the second optical system and the effective focal length f of the second optical system may satisfy: 7.0 < TTL / f < 9.5. By controlling the above conditional expressions, the optical power of the system can be reasonably distributed, ensuring that the fourth lens of the first optical system has good light bending ability; and the second optical system has a smaller focal length within the defined TTL range, enabling better field light to be obtained.

[0069] In an exemplary embodiment, the effective focal length f1' of the first element group, the dispersion coefficient V1' of the first lens, the dispersion coefficient VR of the reflective polarizing element, the dispersion coefficient VQ1 of the first quarter-wave plate, the effective focal length f2' of the second element group, the dispersion coefficient V2' of the second lens, the dispersion coefficient VQ2 of the second quarter-wave plate, the central thickness CT1' of the first element group on the first optical axis, and the central thickness CT2' of the second element group on the first optical axis may satisfy: 15.0 < [f1' / (V1' + VR + VQ1) + f2' / (V2' + VQ2)] / (CT1' + CT2') < 21.0. By controlling this conditional expression, the dispersion coefficients of the system are reasonably distributed, improving the chromatic aberration of the system. By indirectly controlling the effective focal lengths of the first element group and the second element group of the first optical system, it is beneficial to reduce the sensitivity of the system, thereby improving the performance yield.

[0070] In an exemplary embodiment, the effective focal length f3' of the third lens and the effective focal length f'4 of the fourth lens in the first optical system may satisfy: 0 < (f3' + f4') / (f3' - f4') < 2.0. By controlling this conditional expression, the optical power of the system is reasonably distributed, ensuring that the third and fourth lenses have good light transition ability.

[0071] In an exemplary embodiment, the curvature radius R2' of the second side surface of the first lens, the curvature radius R6' of the second side surface of the third lens, the air gap T12' between the first element group and the second element group on the first optical axis, the dispersion coefficient V2' of the second lens, the air gap T23' between the second element group and the third element group on the first optical axis, and the dispersion coefficient V3' of the third lens may satisfy: -11.0 < (R2' + R6') / (T12'×V2' + T23'×V3') < -7.0. By controlling this conditional expression, the shapes of the first lens and the third lens of the first optical system can be reasonably controlled, ensuring the uniformity of the lens and reducing the risk that the lens surface shape has a large impact on the performance of the optical system; at the same time, the effect of balancing chromatic aberration and aberration can be achieved, improving the imaging quality of the system.

[0072] In an exemplary embodiment, the radius of curvature R7' of the first side surface of the fourth lens, the radius of curvature R8' of the second side surface of the fourth lens, the effective focal length f' of the first optical system, and the effective focal length f4' of the fourth lens in the first optical system may satisfy: -7.5 < (R7' - R8') / (f' - f4') < -6.0. By controlling this conditional expression, the surface shape of the fourth lens of the first optical system can be constrained to ensure the uniformity and processability of the lens; at the same time, the optical power of the system can be reasonably distributed to ensure that the fourth lens has good light focusing.

[0073] In an exemplary embodiment, the effective focal length f' of the first optical system and the distance T01 on the first optical axis from the first side surface of the first element group in the first optical system to the entrance pupil position of the first optical system may satisfy: 1.0 < f' / T01 < 1.5. By controlling this conditional expression, it can be ensured that the first optical system has an appropriate focal length, can be adapted to a smaller screen and a larger focal length, and can also ensure that the distance on the optical axis from the first side surface of the first element group of the first optical system to the entrance pupil position is sufficient, indirectly improving the wearing comfort of the human eye.

[0074] In an exemplary embodiment, the effective focal length f' of the first optical system and the radius of curvature R2' of the second side surface of the first lens may satisfy: -0.5 < f' / R2' < 0. By controlling this conditional expression, the optical power of the system is reasonably distributed to ensure that the first lens has a large light bending ability.

[0075] In an exemplary embodiment, the refractive index N1' of the first lens, the refractive index N2' of the second lens, the radius of curvature R2' of the second side surface of the first lens, the refractive index N3' of the third lens, and the radius of curvature R6' of the second side surface of the third lens in the first optical system may satisfy: 11.0 mm < (N1' - N2') × R2' - (N2' - N3') × R6' < 16.0 mm. By controlling this conditional expression, the optical power of the system is reasonably distributed, indirectly controlling the surface shapes of the second and third lenses, which is beneficial to reducing the sensitivity of the system and thus improving the performance yield.

[0076] In an exemplary embodiment, the fourth lens and the fifth lens in the second optical system may be cemented to form a cemented lens, and the effective focal length f of the second optical system and the combined focal length f45 of the fourth lens and the fifth lens may satisfy: 0 < f / f45 < 0.6. By controlling this conditional expression, the optical power of the system is reasonably distributed to ensure that the fourth lens and the fifth lens have good light transition ability.

[0077] In an exemplary embodiment, the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, the refractive index N1 of the first lens, the refractive index N2 of the second lens, and the air gap T12 between the first lens and the second lens on the second optical axis in the second optical system may satisfy: 14.0 < (f1 + f2) × (N1 + N2) / T12 < 19.0. By controlling this conditional expression, the focal lengths of the first and second lenses of the second optical system can be ensured to be within a reasonable range, ensuring the reasonable incidence of large-angle light, reducing aberrations, and improving the imaging quality; at the same time, chromatic aberration and off-axis aberration can be adjusted to ensure a high imaging effect of the system.

[0078] In an exemplary embodiment, the on-axis distance SD from the aperture stop of the second optical system to the image side of the fifth lens and half of the diagonal length ImgH of the effective pixel region on the imaging surface of the second optical system may satisfy: 1.1 < SD / ImgH < 1.6. By controlling this conditional expression, the overall length of the system can be indirectly controlled; the size of the image surface can also be controlled to ensure a large imaging surface to improve the imaging effect.

[0079] In an exemplary embodiment, the curvature radius R1 of the object side of the first lens, the curvature radius R2 of the image side of the first lens, and the curvature radius R10 of the image side of the fifth lens in the second optical system may satisfy: -3.6 < (R1 + R2) / R10 < -0.5. By controlling this conditional expression, the shape of the lens can be reasonably controlled, ensuring the uniformity of the lens, and reducing the risk that the surface shape non-uniformity of the first lens and the fifth lens has a great impact on the performance of the optical system.

[0080] In an exemplary embodiment, the central thickness CT4 of the fourth lens on the second optical axis, the central thickness CT5 of the fifth lens on the second optical axis, the curvature radius R8 of the image side of the fourth lens, and the curvature radius R10 of the image side of the fifth lens in the second optical system may satisfy: -1.0 < (CT4 + CT5) / (R8 + R10) < 0. By controlling this conditional expression, the processability of the lens and the aberration correction ability can be ensured; the surface shapes of the object side and the image side of the fourth lens and the fifth lens can be constrained to ensure the uniformity and processability of the lens.

[0081] In an exemplary embodiment, the dispersion coefficient V1 of the first lens, the dispersion coefficient V2 of the second lens, the central thickness CT1 of the first lens on the second optical axis, the central thickness CT2 of the second lens on the second optical axis, and the effective focal length f1 of the first lens in the second optical system may satisfy: -35.0 < (V1 + V2) × (CT1 + CT2) / f1 < -20.0. By controlling this conditional expression, the thickness of the lens can be reasonably controlled to ensure the processability of the first lens and the second lens; at the same time, the effect of balancing chromatic aberration and aberration can be achieved, improving the imaging quality of the system.

[0082] In an exemplary embodiment, the dispersion coefficient V2 of the second lens, the dispersion coefficient V3 of the third lens, the air gap T23 between the second and third lenses on the second optical axis, the center thickness CT2 of the second lens on the second optical axis, and the center thickness CT3 of the third lens on the second optical axis in the second optical system can satisfy: (|V2-V3|×T23) / [(V2+V3)×(CT2+CT3)]<1.0. By controlling this conditional expression, the thickness of the lenses is reasonably controlled, ensuring the manufacturability of the second and third lenses; at the same time, it can achieve the effect of balancing chromatic aberration and aberration, improving the imaging quality of the system.

[0083] In an exemplary embodiment, the first element group in the first optical system may have positive optical power; the second element group may have negative optical power; the third lens may have positive optical power; and the fourth lens may have positive optical power.

[0084] The virtual reality system according to the above embodiments of this application comprises a first optical system and a second optical system. The first optical system may employ multiple lenses, such as the four lenses described above, and the second optical system may employ multiple lenses, such as the five lenses described above. By rationally configuring the parameters of the first and second optical systems, system performance can be improved, enhancing the imaging quality and visual immersion of the virtual reality system. The eyepiece (first optical system) and the positioning lens (second optical system) work together to strengthen the positioning function of the controller, greatly improving the user experience. Furthermore, the virtual reality system configured as described above features miniaturization and good imaging quality, effectively meeting the usage needs of various portable electronic products in projection scenarios.

[0085] In embodiments of this application, at least one of the mirror surfaces of the first to fourth lenses in the first optical system can be aspherical mirror surfaces. Aspherical lenses are characterized by a continuously changing curvature from the lens center to the lens periphery. Unlike spherical lenses, which have a constant curvature from the lens center to the lens periphery, aspherical lenses have better radius of curvature characteristics, offering advantages in improving distortion aberrations and astigmatism. By using aspherical lenses, aberrations occurring during imaging can be eliminated as much as possible, thereby improving image quality. Similarly, at least one of the mirror surfaces of the first to fifth lenses in the second optical system can also be aspherical mirror surfaces.

[0086] However, those skilled in the art should understand that, without departing from the technical solutions claimed in this application, the number of lenses and / or mirrors constituting the optical system can be changed to obtain the various results and advantages described in this specification.

[0087] refer to Figure 1, in the second aspect of the present application, there is provided a virtual reality system, which may include a first optical system and a second optical system. The first optical system sequentially includes a first element group, a second element group, a third element group, and a fourth element group along a first optical axis from a first side to a second side. Among them, the first element group may include a first lens, a reflective polarizing element, and a first quarter-wave plate; the second element group may include a second lens and a second quarter-wave plate; the third element group may include a third lens; the fourth element group may include a fourth lens. The second optical system sequentially includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens along a second optical axis from an object side to an image side.

[0088] Among them, the real image formed by the second optical system is transmitted to the first optical system in the form of an electrical signal. The first optical system is used to project a virtual reality image and a real image on an image plane provided on the second side. And the maximum field of view FOV of the second optical system and the maximum field of view FOV' of the first optical system may satisfy: 1.3 < FOV / FOV' < 1.8. By constraining the ratio of the maximum field of view of the second optical system to that of the first optical system within a reasonable range, it can be ensured to the greatest extent that the environmental field of view collected by the second optical system is large enough, and it can be ensured that the handle can be detected within the maximum limit, so as to give the user sufficient feedback.

[0089] Reference Figure 1 , in the third aspect of the present application, there is provided a virtual reality system, which may include a first optical system and a second optical system. The first optical system sequentially includes a first element group, a second element group, a third element group, and a fourth element group along a first optical axis from a first side to a second side. Among them, the first element group may include a first lens, a reflective polarizing element, and a first quarter-wave plate; the second element group may include a second lens and a second quarter-wave plate; the third element group may include a third lens; the fourth element group may include a fourth lens. The second optical system sequentially includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens along a second optical axis from an object side to an image side.

[0090] Among them, the real image formed by the second optical system is transmitted to the first optical system in the form of an electrical signal. The first optical system is used to project a virtual reality image and a real image on an image plane provided on the second side. And the effective focal length f' of the first optical system and the effective focal length f of the second optical system may satisfy: 8.0 < f' / f < 15.0. By reasonably constraining the ratio of the effective focal lengths of the first optical system and the second optical system, it helps to ensure the performance combination of the first optical system and the second optical system; it helps to control the second optical system to have a smaller focal length, which is beneficial for the second optical system to have a smaller image plane and a larger field of view to receive environmental light, so as to locate the position of the handle, which is beneficial for the imaging of the second optical system.

[0091] The following describes a specific embodiment of the first optical system applicable to the above-described embodiments with reference to the accompanying drawings.

[0092] Example 1

[0093] The following is for reference Figures 3 to 6 A first optical system according to Embodiment 1 of this application is described.

[0094] like Figure 3 As shown, the first optical system 100 includes a first element group, a second element group, a third element group, and a fourth element group arranged sequentially along the optical axis from a first side to a second side. The first element group includes a reflective polarizing element RP, a first quarter-wave plate QWP1, and a first lens E1'. The second element group includes a second quarter-wave plate QWP2 and a second lens E2'. The third element group includes a third lens E3'. The fourth element group includes a fourth lens E4'. In this embodiment, the first optical system 100 also includes a third quarter-wave plate QWP3 located on the second side of the fourth element group and an image plane IMG.

[0095] In this embodiment, the first side can be the human eye side, and the second side can be the display screen side. The first side of each component (reflective polarizing element RP, first quarter-wave plate QWP1, first lens E1', second quarter-wave plate QWP2, second lens E2', third lens E3', fourth lens E4', etc.) is referred to as the side near the human eye, and the second side is referred to as the side near the screen.

[0096] In this embodiment, the reflective polarizing element RP has a near-eye side S1 and a near-screen side. The near-screen side of the reflective polarizing element RP is attached to the near-eye side S2 of the first quarter-wave plate QWP1. The near-screen side of the first quarter-wave plate QWP1 is attached to the near-eye side S3 of the first lens E1'. The first lens E1' also has a near-screen side S4. The first element group consisting of the reflective polarizing element RP, the first quarter-wave plate QWP1, and the first lens E1' has positive optical power. The second quarter-wave plate QWP2 has a near-eye side S5 and a near-screen side. The near-screen side of the second quarter-wave plate QWP2 is attached to the near-eye side S6 of the second lens E2'. The second lens E2' also has a near-screen side S7. The second element group consisting of the second quarter-wave plate QWP2 and the second lens E2' has negative optical power. The third lens E3' has positive optical power and has a near-eye side S8 and a near-screen side S9. The fourth lens E4' has positive optical power and has a near-eye side S10 and a near-screen side S11. The third quarter-wave plate QWP3 has a near-eye side S12 and a near-screen side. The near-screen side of the third quarter-wave plate QWP3 can be attached to the near-eye side S13 of the image surface IMG. The image surface IMG also has a surface S14.

[0097] In this embodiment, the image surface IMG disposed on the second side of the first optical system 100 may, for example, be a display screen. Image light from the display screen sequentially passes through the third quarter-wave plate QWP3, the fourth lens E4', the third lens E3', the second lens E2', the second quarter-wave plate QWP2, the first lens E1', and the first quarter-wave plate QWP1 to reach the near-screen side of the reflective polarizing element RP, where a first reflection occurs. The light after the first reflection passes through the first quarter-wave plate QWP1 and the first lens E1' to reach the near-screen side S4 of the first lens E1', where a second reflection occurs. The light after the second reflection sequentially passes through the first lens E1', the first quarter-wave plate QWP1, and the reflective polarizing element RP and is finally projected onto a target object (not shown) in space. For example, the light from the first optical system 100 after two reflections can finally be projected into the user's eye. A partial reflective layer BS may, for example, be disposed at the near-screen side S4 of the first lens E1'.

[0098] Table 1 shows the basic parameters of the first optical system of Embodiment 1, where the units for radius of curvature and thickness / distance are millimeters (mm). Image light from the display screen (monitor) passes through each element in sequence from number 20 to the object surface and is finally projected into the human eye.

[0099]

[0100]

[0101] Table 1

[0102] In this embodiment, the effective focal length f1' of the first element group is 12.35 mm, the effective focal length f2' of the second element group is -193.70 mm, the effective focal length f3' of the third lens E3' is 71.23 mm, the effective focal length f4' of the fourth lens E4' is 17.79 mm, the total effective focal length f' of the first optical system is 11.25 mm, the maximum field of view FOV' of the first optical system is 110.0°, and the entrance pupil diameter EPD' of the first optical system is 4.00 mm.

[0103] In this embodiment, the near-screen side S4 of the first lens E1', the near-screen side S7 of the second lens E2', the near-eye side S8 and the near-screen side S9 of the third lens E3', and the near-eye side S10 and the near-screen side S11 of the fourth lens E4' are all aspherical. The surface shape x of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0104]

[0105] Where x is the distance vector from the vertex of the aspherical surface at a height of h along the optical axis; 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 is the conic coefficient; Ai is the i-th order correction coefficient of the aspherical surface. Tables 2-1 and 2-2 give the higher-order coefficients A4, A6, A8, A10, A20, A11 that can be used for the aspherical mirrors S4, S7-S11 in Example 1. 10 A 12 A 14 A 16 A 18 A 20 A 22 A 24 A 26 A 28 and A 30 .

[0106] Number / Coefficient A4 A6 A8 A10 A12 A14 A16 S4 3.4631E-01 1.7349E-02 -2.1959E-02 -3.8865E-03 1.6460E-03 4.2290E-04 1.2024E-04 S7 1.9414E+00 -1.9955E+00 6.8980E-01 -8.9582E-02 -1.4447E-02 -2.4869E-02 9.1373E-03 S8 3.9257E+00 -1.5938E+00 5.4740E-01 -1.9444E-01 2.8427E-02 -1.8808E-02 2.6889E-03 S9 1.5113E+00 6.1962E-02 -1.3206E-02 -7.5498E-02 3.6147E-02 1.4696E-03 1.2219E-02 S10 -2.4997E+00 4.8089E-01 2.0797E-01 1.9151E-01 -8.6395E-02 -7.0430E-02 -8.0943E-03 S11 5.9839E+00 -6.2026E-01 4.4193E-01 -4.4822E-01 1.3083E-01 -1.1395E-01 1.1292E-01

[0107] Table 2-1

[0108] Number / Coefficient A18 A20 A22 A24 A26 A28 A30 S4 -5.4045E-04 -1.7521E-04 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S7 -4.9533E-03 1.1891E-03 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S8 -4.8332E-04 9.9544E-03 8.2879E-04 -1.5382E-03 3.3749E-04 -9.2403E-04 3.3040E-04 S9 4.3318E-02 2.4856E-02 -1.3026E-02 -2.4151E-02 -1.0752E-02 1.0956E-02 -7.5977E-04 S10 6.4787E-02 5.7288E-02 -2.7334E-02 -5.8990E-02 -2.2251E-02 5.7454E-02 2.2619E-02 S11 -6.7509E-02 6.3594E-02 -4.4459E-02 3.0919E-02 -3.2881E-02 2.0899E-02 -4.8703E-03

[0109] Table 2-2

[0110] Figure 4The on-axis chromatic aberration curve of the first optical system of Embodiment 1 is shown, which represents the deflection of the focal point of light of different wavelengths after passing through the first optical system. Figure 5 The astigmatism curves of the first optical system of Embodiment 1 are shown, which represent the meridional image plane curvature and sagittal image plane curvature corresponding to different field of view angles. Figure 6 The distortion curves of the first optical system in Embodiment 1 are shown, representing the distortion magnitudes corresponding to different field of view angles. According to... Figures 4 to 6 As can be seen, the first optical system given in Example 1 can achieve good imaging quality.

[0111] Example 2

[0112] The following is for reference Figures 7 to 10 A first optical system according to Embodiment 2 of this application is described.

[0113] like Figure 7 As shown, the first optical system 100 includes a first element group, a second element group, a third element group, and a fourth element group arranged sequentially along the optical axis from a first side to a second side. The first element group includes a reflective polarizing element RP, a first quarter-wave plate QWP1, and a first lens E1'. The second element group includes a second quarter-wave plate QWP2 and a second lens E2'. The third element group includes a third lens E3'. The fourth element group includes a fourth lens E4'. In this embodiment, the first optical system 100 also includes a third quarter-wave plate QWP3 located on the second side of the fourth element group and an image plane IMG.

[0114] In this embodiment, the first side can be the human eye side, and the second side can be the display screen side. The first side of each component (reflective polarizing element RP, first quarter-wave plate QWP1, first lens E1', second quarter-wave plate QWP2, second lens E2', third lens E3', fourth lens E4', etc.) is referred to as the side near the human eye, and the second side is referred to as the side near the screen.

[0115] In this embodiment, the reflective polarizing element RP has a near-eye side S1 and a near-screen side. The near-screen side of the reflective polarizing element RP is attached to the near-eye side S2 of the first quarter-wave plate QWP1. The near-screen side of the first quarter-wave plate QWP1 is attached to the near-eye side S3 of the first lens E1'. The first lens E1' also has a near-screen side S4. The first element group consisting of the reflective polarizing element RP, the first quarter-wave plate QWP1, and the first lens E1' has positive optical power. The second quarter-wave plate QWP2 has a near-eye side S5 and a near-screen side. The near-screen side of the second quarter-wave plate QWP2 is attached to the near-eye side S6 of the second lens E2'. The second lens E2' also has a near-screen side S7. The second element group consisting of the second quarter-wave plate QWP2 and the second lens E2' has negative optical power. The third lens E3' has positive optical power and has a near-eye side S8 and a near-screen side S9. The fourth lens E4' has positive optical power and has a near-eye side S10 and a near-screen side S11. The third quarter-wave plate QWP3 has a near-eye side S12 and a near-screen side. The near-screen side of the third quarter-wave plate QWP3 can be attached to the near-eye side S13 of the image surface IMG. The image surface IMG also has a surface S14.

[0116] In this embodiment, the image surface IMG disposed on the second side of the first optical system 100 may, for example, be a display screen. Image light from the display screen sequentially passes through the third quarter-wave plate QWP3, the fourth lens E4', the third lens E3', the second lens E2', the second quarter-wave plate QWP2, the first lens E1', and the first quarter-wave plate QWP1, and reaches the near-screen side of the reflective polarizing element RP, where it undergoes a first reflection. The light after the first reflection passes through the first quarter-wave plate QWP1 and the first lens E1' and reaches the near-screen side S4 of the first lens E1', where it undergoes a second reflection. The light after the second reflection sequentially passes through the first lens E1', the first quarter-wave plate QWP1, and the reflective polarizing element RP, and is finally projected onto a target object (not shown) in space. For example, the light from the first optical system 100 after two reflections can finally be projected into the user's eye. A partial reflective layer BS may, for example, be disposed at the near-screen side S4 of the first lens E1'.

[0117] Table 3 shows the basic parameters of the first optical system in Embodiment 2, where the units for radius of curvature and thickness / distance are millimeters (mm). Image light from the display screen (monitor) passes through each element in sequence from number 20 to the object surface and is finally projected into the human eye.

[0118]

[0119] Table 3

[0120] In this embodiment, the effective focal length f1' of the first element group is 12.47 mm, the effective focal length f2' of the second element group is -1788.64 mm, the effective focal length f3' of the third lens E3' is 154.30 mm, the effective focal length f4' of the fourth lens E4' is 16.49 mm, the total effective focal length f' of the first optical system is 11.16 mm, the maximum field of view FOV' of the first optical system is 100.0°, and the entrance pupil diameter EPD' of the first optical system is 3.20 mm.

[0121] In this embodiment, the near-screen side S4 of the first lens E1', the near-screen side S7 of the second lens E2', the near-eye side S8 and near-screen side S9 of the third lens E3', and the near-eye side S10 and near-screen side S11 of the fourth lens E4' are all aspherical surfaces, and the surface shape of each aspherical surface can be defined by formula (1) given in Embodiment 1 above. Tables 4-1 and 4-2 give the higher-order coefficients A4, A6, A8, and A11 that can be used for each aspherical mirror surface S4, S7-S11 in Embodiment 2. 10 A 12 A 14 A 16 A 18 A 20 A 22 A 24 A 26 A 28 and A 30 .

[0122] Number / Coefficient A4 A6 A8 A10 A12 A14 A16 S4 4.0507E-01 -9.7521E-04 9.8533E-03 -1.0898E-02 2.2359E-03 -1.6931E-03 1.2606E-03 S7 -2.3396E-01 -5.9523E-02 -4.0733E-02 3.0980E-02 -6.2339E-03 6.6225E-03 -4.5979E-03 S8 3.6172E+00 -7.1397E-01 3.5204E-01 -1.6926E-01 6.8579E-02 -4.3574E-02 1.3397E-02 S9 1.4782E+00 -4.4897E-01 1.6446E-01 -7.5305E-02 4.0404E-02 -2.9539E-02 7.6127E-03 S10 -2.8597E+00 8.0379E-01 -3.0951E-01 1.7621E-01 -8.6553E-02 3.1946E-02 7.6151E-03 S11 5.8000E+00 -1.0412E+00 6.5245E-01 -3.7185E-01 2.0424E-01 -1.4671E-01 1.0293E-01

[0123] Table 4-1

[0124] Number / Coefficient A18 A20 A22 A24 A26 A28 A30 S4 -6.4757E-04 1.6890E-04 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S7 -2.7775E-03 4.2593E-03 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S8 -2.5877E-03 6.1901E-03 2.3813E-03 -2.1571E-03 -1.3107E-03 -7.1599E-04 -7.8328E-04 S9 1.7334E-02 3.9287E-03 -4.3169E-03 -2.1883E-03 1.3586E-03 -2.9655E-03 1.3154E-03 S10 -2.1742E-03 1.0169E-02 -1.6729E-02 9.3804E-03 -2.1717E-03 5.0822E-04 -9.1804E-05 S11 -6.2282E-02 5.2324E-02 -4.3757E-02 3.0645E-02 -3.2821E-02 2.2228E-02 -5.1604E-03

[0125] Table 4-2

[0126] Figure 8 The on-axis chromatic aberration curve of the first optical system of Embodiment 2 is shown, which represents the deflection of the focal point of light of different wavelengths after passing through the first optical system. Figure 9 The astigmatism curves of the first optical system of Embodiment 2 are shown, which represent the meridional image plane curvature and sagittal image plane curvature corresponding to different field of view angles. Figure 10 The distortion curves of the first optical system in Embodiment 2 are shown, representing the distortion magnitudes corresponding to different field of view angles. According to... Figures 8 to 10 It can be seen that the first optical system given in Embodiment 2 can achieve good imaging quality.

[0127] Example 3

[0128] The following is for reference Figures 11 to 14 The first optical system according to Embodiment 3 of this application is described.

[0129] like Figure 11 As shown, the first optical system 100 includes a first element group, a second element group, a third element group, and a fourth element group arranged sequentially along the optical axis from a first side to a second side. The first element group includes a reflective polarizing element RP, a first quarter-wave plate QWP1, and a first lens E1'. The second element group includes a second quarter-wave plate QWP2 and a second lens E2'. The third element group includes a third lens E3'. The fourth element group includes a fourth lens E4'. In this embodiment, the first optical system 100 also includes a third quarter-wave plate QWP3 located on the second side of the fourth element group and an image plane IMG.

[0130] In this embodiment, the first side refers to the human eye side, and the second side refers to the display screen side. The first side of each component (reflective polarizing element RP, first quarter-wave plate QWP1, first lens E1', second quarter-wave plate QWP2, second lens E2', third lens E3', fourth lens E4', etc.) is referred to as the side near the human eye, and the second side is referred to as the side near the screen.

[0131] In this embodiment, the reflective polarizing element RP has a near-eye side S1 and a near-screen side. The near-screen side of the reflective polarizing element RP is attached to the near-eye side S2 of the first quarter-wave plate QWP1. The near-screen side of the first quarter-wave plate QWP1 is attached to the near-eye side S3 of the first lens E1'. The first lens E1' also has a near-screen side S4. The first element group consisting of the reflective polarizing element RP, the first quarter-wave plate QWP1, and the first lens E1' has positive optical power. The second quarter-wave plate QWP2 has a near-eye side S5 and a near-screen side. The near-screen side of the second quarter-wave plate QWP2 is attached to the near-eye side S6 of the second lens E2'. The second lens E2' also has a near-screen side S7. The second element group consisting of the second quarter-wave plate QWP2 and the second lens E2' has negative optical power. The third lens E3' has positive optical power and has a near-eye side S8 and a near-screen side S9. The fourth lens E4' has positive optical power and has a near-eye side S10 and a near-screen side S11. The third quarter-wave plate QWP3 has a near-eye side S12 and a near-screen side. The near-screen side of the third quarter-wave plate QWP3 can be attached to the near-eye side S13 of the image surface IMG. The image surface IMG also has a surface S14.

[0132] In this embodiment, the image surface IMG disposed on the second side of the first optical system 100 may, for example, be a display screen. Image light from the display screen sequentially passes through the third quarter-wave plate QWP3, the fourth lens E4', the third lens E3', the second lens E2', the second quarter-wave plate QWP2, the first lens E1', and the first quarter-wave plate QWP1, and reaches the near-screen side of the reflective polarizing element RP, where it undergoes a first reflection. The light after the first reflection passes through the first quarter-wave plate QWP1 and the first lens E1' and reaches the near-screen side S4 of the first lens E1', where it undergoes a second reflection. The light after the second reflection sequentially passes through the first lens E1', the first quarter-wave plate QWP1, and the reflective polarizing element RP, and is finally projected onto a target object (not shown) in space. For example, the light from the first optical system 100 after two reflections is finally projected into the user's eye. A partial reflective layer BS may, for example, be disposed at the near-screen side S4 of the first lens E1'.

[0133] Table 5 shows the basic parameters of the first optical system in Embodiment 3, where the units for radius of curvature and thickness / distance are millimeters (mm). Image light from the display screen (monitor) passes through each element in sequence from number 20 to the object surface and is finally projected into the human eye.

[0134]

[0135] Table 5

[0136] In this embodiment, the effective focal length f1' of the first element group is 12.47 mm, the effective focal length f2' of the second element group is -1792.22 mm, the effective focal length f3' of the third lens E3' is 154.61 mm, the effective focal length f4' of the fourth lens E4' is 16.52 mm, the total effective focal length f' of the first optical system is 11.17 mm, the maximum field of view FOV' of the first optical system is 104.0°, and the entrance pupil diameter EPD' of the first optical system is 4.00 mm.

[0137] In this embodiment, the near-screen side S4 of the first lens E1', the near-screen side S7 of the second lens E2', the near-eye side S8 and the near-screen side S9 of the third lens E3', and the near-eye side S10 and the near-screen side S11 of the fourth lens E4' are all aspherical surfaces, and the surface shape of each aspherical surface can be defined by formula (1) given in Embodiment 1 above. Tables 6-1 and 6-2 give the higher-order coefficients A4, A6, A8, and A11 that can be used for each aspherical mirror surface S4, S7-S11 in Embodiment 3. 10 A 12 A14 A 16 A 18 A 20 A 22 A 24 A 26 A 28 and A 30 .

[0138] Number / Coefficient A4 A6 A8 A10 A12 A14 A16 S4 4.0507E-01 -9.7521E-04 9.8533E-03 -1.0898E-02 2.2359E-03 -1.6931E-03 1.2606E-03 S7 -2.3443E-01 -5.9642E-02 -4.0815E-02 3.1042E-02 -6.2464E-03 6.6358E-03 -4.6071E-03 S8 3.6244E+00 -7.1540E-01 3.5275E-01 -1.6960E-01 6.8716E-02 -4.3661E-02 1.3424E-02 S9 1.4811E+00 -4.4986E-01 1.6479E-01 -7.5455E-02 4.0485E-02 -2.9599E-02 7.6279E-03 S10 -2.8654E+00 8.0539E-01 -3.1013E-01 1.7657E-01 -8.6726E-02 3.2010E-02 7.6303E-03 S11 5.8116E+00 -1.0432E+00 6.5375E-01 -3.7260E-01 2.0465E-01 -1.4701E-01 1.0314E-01

[0139] Table 6-1

[0140] Number / Coefficient A18 A20 A22 A24 A26 A28 A30 S4 -6.4757E-04 1.6890E-04 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S7 -2.7830E-03 4.2679E-03 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S8 -2.5929E-03 6.2025E-03 2.3861E-03 -2.1614E-03 -1.3133E-03 -7.1742E-04 -7.8485E-04 S9 1.7369E-02 3.9366E-03 -4.3255E-03 -2.1927E-03 1.3613E-03 -2.9714E-03 1.3181E-03 S10 -2.1786E-03 1.0189E-02 -1.6763E-02 9.3992E-03 -2.1761E-03 5.0924E-04 -9.1988E-05 S11 -6.2407E-02 5.2428E-02 -4.3844E-02 3.0706E-02 -3.2887E-02 2.2272E-02 -5.1708E-03

[0141] Table 6-2

[0142] Figure 12 The on-axis chromatic aberration curve of the first optical system of Embodiment 3 is shown, which represents the deflection of the focal point of light of different wavelengths after passing through the first optical system. Figure 13 The astigmatism curves of the first optical system of Embodiment 3 are shown, which represent the meridional image plane curvature and sagittal image plane curvature corresponding to different field of view angles. Figure 14 The distortion curves of the first optical system in Embodiment 3 are shown, representing the distortion magnitudes corresponding to different field of view angles. According to... Figures 12 to 14 It can be seen that the first optical system given in Embodiment 3 can achieve good imaging quality.

[0143] In Examples 1 to 3, the total effective focal length f' of the first optical system, the effective focal length f1' of the first element group, the effective focal length f2' of the second element group, the effective focal length f3' of the third lens E3', the effective focal length f4' of the fourth lens E4', the maximum field of view FOV' of the first optical system, and the entrance pupil diameter EPD' of the first optical system are shown in Table 7.

[0144]

[0145]

[0146] Table 7

[0147] The following describes a specific embodiment of the second optical system applicable to the above embodiments with reference to the accompanying drawings.

[0148] Example 4

[0149] The following is for reference Figures 15 to 18 A second optical system according to Embodiment 4 of this application is described.

[0150] like Figure 15As shown, the second optical system 200 includes a first lens E1, a second lens E2, a third lens E3, an aperture stop STO, a fourth lens E4, a fifth lens E5, a filter E6, and an imaging plane arranged sequentially along the optical axis from the object side to the image side. The fourth lens E4 and the fifth lens E5 are cemented together to form a cemented doublet lens.

[0151] In this embodiment, the first lens E1 has negative optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative optical power, with its object-side surface S3 being concave and its image-side surface S4 being concave. The third lens E3 has positive optical power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has positive optical power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fifth lens E5 has negative optical power, with its object-side surface S8 being concave and its image-side surface S9 being convex. The filter E6 has an object-side surface S10 and an image-side surface S11. Light from the object passes sequentially through each surface S1 to S11 and is finally imaged onto the imaging surface S12.

[0152] Table 8 shows the basic parameters of the second optical system in Embodiment 4, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0153]

[0154] Table 8

[0155] In this embodiment, the object-side surface and image-side surface of any one of the second lens E2 to the fifth lens E5 are aspherical, and the surface shape x of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0156]

[0157] Where x is the distance vector from the vertex of the aspherical surface at a height of h along the optical axis; 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 is the conic coefficient; Ai is the i-th order correction coefficient of the aspherical surface. Table 9 gives the higher-order coefficients A4, A6, A8, A9 that can be used for each aspherical mirror S3-S9 in Example 4. 10 A 12 A 14 and A 16 .

[0158] Number / Coefficient A4 A6 A8 A10 A12 A14 A16 S3 1.3155E-02 -3.6933E-03 3.4686E-04 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S4 6.5174E-02 -2.1988E-02 1.1033E-01 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S5 7.4294E-02 -1.8085E-01 1.9049E+00 -6.9085E+00 1.4141E+01 -1.4612E+01 6.2110E+00 S6 8.7839E-02 -1.3037E-01 1.2584E+00 -2.2938E+00 9.7644E-01 3.1835E+00 -1.0456E+00 S7 4.1361E-02 -3.2929E-01 2.5555E+00 -9.8149E+00 2.1131E+01 -2.3910E+01 1.1126E+01 S8 -1.4142E+00 3.8135E+00 -5.1918E+00 1.2281E+01 -1.8193E+01 1.0674E+01 8.1662E-01 S9 -7.1809E-02 4.9566E-01 -3.1180E-01 8.7678E-01 -2.7390E+00 3.9152E+00 -1.9157E+00

[0159] Table 9

[0160] Figure 16The on-axis chromatic aberration curve of the second optical system of Embodiment 4 is shown, which represents the deflection of the focal point of light of different wavelengths after passing through the second optical system. Figure 17 The astigmatism curves of the second optical system in Embodiment 4 are shown, which represent the meridional image plane curvature and sagittal image plane curvature corresponding to different field of view angles. Figure 18 The f-θ distortion curve of the second optical system in Embodiment 4 is shown, representing the distortion magnitude at different field angles. According to... Figures 16 to 18 As can be seen, the second optical system given in Example 4 can achieve good imaging quality.

[0161] Example 5

[0162] The following is for reference Figures 19 to 22 A second optical system according to Embodiment 5 of this application is described.

[0163] like Figure 19 As shown, the second optical system 200 includes a first lens E1, a second lens E2, a third lens E3, an aperture stop STO, a fourth lens E4, a fifth lens E5, a filter E6, and an imaging plane arranged sequentially along the optical axis from the object side to the image side. The fourth lens E4 and the fifth lens E5 are cemented together to form a cemented doublet lens.

[0164] In this embodiment, the first lens E1 has negative optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative optical power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has positive optical power, with its object-side surface S5 being convex and its image-side surface S6 being convex. The fourth lens E4 has negative optical power, with its object-side surface S7 being convex and its image-side surface S8 being concave. The fifth lens E5 has positive optical power, with its object-side surface S8 being convex and its image-side surface S9 being convex. The filter E6 has an object-side surface S10 and an image-side surface S11. Light from the object passes sequentially through each surface S1 to S11 and is finally imaged onto the imaging surface S12.

[0165] Table 10 shows the basic parameters of the second optical system in Embodiment 5, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0166]

[0167]

[0168] Table 10

[0169] In this embodiment, the object-side and image-side surfaces of any one of the second lens E2 to the fifth lens E5 are aspherical, and the surface shape of each aspherical surface can be defined by formula (1) given in Embodiment 4 above. Table 11 gives the higher-order coefficients A4, A6, A8 and A9 that can be used for each aspherical mirror S3-S9 in Embodiment 5. 10 .

[0170] Number / Coefficient A4 A6 A8 A10 S3 3.0393E-02 -9.4980E-03 1.3270E-03 -1.0643E-04 S4 8.7480E-02 3.4807E-02 2.5571E-02 2.6720E-02 S5 -2.8300E-02 -1.7206E-02 0.0000E+00 0.0000E+00 S6 6.9885E-02 -5.5844E-02 5.1467E-02 -1.8065E-02 S7 1.3521E-01 -5.7265E-01 5.4439E-01 -3.3193E-01 S8 1.3891E+00 -2.6572E+00 2.1738E+00 -7.2685E-01 S9 -7.7499E-02 3.9585E-02 -4.6320E-02 2.2691E-02

[0171] Table 11

[0172] Figure 20 The on-axis chromatic aberration curve of the second optical system of Embodiment 5 is shown, which represents the deflection of the focal point of light of different wavelengths after passing through the second optical system. Figure 21 The astigmatism curves of the second optical system in Embodiment 5 are shown, which represent the meridional image plane curvature and sagittal image plane curvature corresponding to different field of view angles. Figure 22 The f-θ distortion curve of the second optical system in Embodiment 5 is shown, representing the distortion magnitude values ​​corresponding to different field of view angles. According to... Figures 20 to 22 As can be seen, the second optical system given in Example 5 can achieve good imaging quality.

[0173] Example 6

[0174] The following is for reference Figures 23 to 26 A second optical system according to Embodiment Six of this application is described.

[0175] like Figure 23 As shown, the second optical system 200 includes a first lens E1, a second lens E2, a third lens E3, an aperture stop STO, a fourth lens E4, a fifth lens E5, a filter E6, and an imaging plane arranged sequentially along the optical axis from the object side to the image side. The fourth lens E4 and the fifth lens E5 are cemented together to form a cemented doublet lens.

[0176] In this embodiment, the first lens E1 has negative optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative optical power, with its object-side surface S3 being concave and its image-side surface S4 being concave. The third lens E3 has positive optical power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has positive optical power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fifth lens E5 has negative optical power, with its object-side surface S8 being concave and its image-side surface S9 being convex. The filter E6 has an object-side surface S10 and an image-side surface S11. Light from the object passes sequentially through each surface S1 to S11 and is finally imaged onto the imaging surface S12.

[0177] Table 12 shows the basic parameters of the second optical system in Embodiment Six, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0178]

[0179] Table 12

[0180] In this embodiment, the object-side surface and image-side surface of any one of the second lens E2 to the fifth lens E5 are aspherical, and the surface shape of each aspherical surface can be defined by formula (1) given in Embodiment 4 above. Table 13 gives the higher-order coefficients A4, A6, A8, and A9 that can be used for each aspherical mirror S3-S9 in Embodiment 6. 10 A 12 A 14 and A 16 .

[0181] Number / Coefficient A4 A6 A8 A10 A12 A14 A16 S3 9.1872E-03 -2.1182E-03 2.2639E-04 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S4 7.0950E-02 1.7984E-02 3.5413E-02 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S5 1.7310E-01 -2.5361E-01 1.2545E+00 -3.4180E+00 5.3508E+00 -4.2483E+00 1.3739E+00 S6 -1.5233E-01 9.3159E-01 -2.2086E+00 3.3356E+00 -2.9783E+00 1.8414E+00 -5.5596E-01 S7 -4.0417E-01 1.2826E+00 -3.8607E+00 7.1462E+00 -8.2517E+00 5.3062E+00 -1.4945E+00 S8 -1.6284E+00 3.8855E+00 -3.6065E+00 3.6282E+00 -2.6240E+00 -6.8892E-01 1.8222E+00 S9 -1.2596E-01 6.8151E-01 -9.3562E-01 2.1473E+00 -3.9656E+00 4.1616E+00 -1.6772E+00

[0182] Table 13

[0183] Figure 24 The on-axis chromatic aberration curve of the second optical system of Embodiment Six is ​​shown, which represents the deflection of the focal point of light of different wavelengths after passing through the second optical system. Figure 25 The astigmatism curves of the second optical system of Embodiment Six are shown, which represent the meridional image plane curvature and sagittal image plane curvature corresponding to different field of view angles. Figure 26 The f-θ distortion curve of the second optical system in Embodiment Six is ​​shown, representing the distortion magnitude values ​​corresponding to different field of view angles. According to... Figures 24 to 26 As can be seen, the second optical system given in Example 6 can achieve good imaging quality.

[0184] Example 7

[0185] The following is for reference Figures 27 to 30 A second optical system according to Embodiment Seven of this application is described.

[0186] like Figure 27 As shown, the second optical system 200 includes a first lens E1, a second lens E2, a third lens E3, an aperture stop STO, a fourth lens E4, a fifth lens E5, a filter E6, and an imaging plane arranged sequentially along the optical axis from the object side to the image side. The fourth lens E4 and the fifth lens E5 are cemented together to form a cemented doublet lens.

[0187] In this embodiment, the first lens E1 has negative optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative optical power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has positive optical power, with its object-side surface S5 being concave and its image-side surface S6 being convex. The fourth lens E4 has negative optical power, with its object-side surface S7 being convex and its image-side surface S8 being concave. The fifth lens E5 has positive optical power, with its object-side surface S8 being convex and its image-side surface S9 being convex. The filter E6 has an object-side surface S10 and an image-side surface S11. Light from the object passes sequentially through each surface S1 to S11 and is finally imaged onto the imaging surface S12.

[0188] Table 14 shows the basic parameters of the second optical system in Embodiment 7, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0189]

[0190] Table 14

[0191] In this embodiment, the object-side surface and image-side surface of any one of the second lens E2 to the fifth lens E5 are aspherical, and the shape of each aspherical surface can be defined by formula (1) given in Embodiment 4 above. Table 15 gives the higher-order term coefficients A4, A6, A8, and A6 that can be used in S3-S9 in Embodiment 7. 10 A 12 A 14 and A 16 .

[0192] Number / Coefficient A4 A6 A8 A10 A12 A14 A16 S3 -2.0176E-01 -5.6870E-01 8.5729E-01 -7.7623E-01 6.8228E-01 -4.6178E-01 1.2237E-01 S4 -3.1393E-01 -5.7639E-01 -3.0452E+00 2.1945E+01 -5.9799E+01 7.8742E+01 -4.0924E+01 S5 5.7085E-02 -2.2822E-01 2.9864E-01 -2.4180E-02 2.3649E-01 -4.2112E-01 2.8952E-01 S6 -1.0685E-01 -4.7255E-02 1.4076E-01 -1.5875E-01 2.3959E-13 -2.1838E-17 5.7346E-19 S7 -9.1966E-02 4.9734E-02 -1.6759E-01 1.7687E-01 -6.1707E-15 -2.7406E-17 -1.3300E-19 S8 5.6387E-01 -1.4083E+00 2.3023E+00 -3.0879E+00 -7.7431E-01 6.2641E+00 -5.0117E+00 S9 -1.1316E-02 7.7736E-02 -3.6213E-01 1.2732E+00 -2.5394E+00 2.6977E+00 -1.1222E+00

[0193] Table 15

[0194] Figure 28 The on-axis chromatic aberration curve of the second optical system of Embodiment 7 is shown, which represents the deflection of the focal point of light of different wavelengths after passing through the second optical system. Figure 29 The astigmatism curves of the second optical system in Embodiment 7 are shown, which represent the meridional image plane curvature and sagittal image plane curvature corresponding to different field of view angles. Figure 30 The f-θ distortion curve of the second optical system in Embodiment 7 is shown, representing the distortion magnitude corresponding to different field of view angles. According to... Figures 28 to 30 It can be seen that the second optical system given in Example 7 can achieve good imaging quality.

[0195] Furthermore, in Embodiments 4 to 7, the distance TTL on the axis from the object side of the first lens E1 of the second optical system to the imaging surface of the second optical system, half the diagonal length ImgH of the effective pixel area on the imaging surface of the second optical system, the maximum field of view FOV of the second optical system, the aperture value Fno of the second optical system, the total effective focal length f of the second optical system, the effective focal lengths f1 to f5 of each lens from the first lens E1 to the fifth lens E5 in the second optical system, and the combined focal length f45 of the fourth lens E4 and the fifth lens E5 are shown in Table 16.

[0196] Parameters / Examples Four five six seven TTL(mm) 7.44 7.70 7.76 7.74 ImgH(mm) 1.19 1.26 1.26 1.30 FOV (°) 166.52 170.01 166.51 170.14 Fno 1.80 1.70 1.79 2.23 f(mm) 0.80 0.89 0.90 1.05 f1(mm) -3.4 -3.6 -4.6 -3.12 f2 (mm) -1.69 -2.12 -1.86 -5.53 f3 (mm) 3.06 1.67 7.93 6.79 f4 (mm) 1.13 -2.90 1.24 -11.11 f5 (mm) -2.38 2.25 -2.09 1.34 f45 (mm) 1.93 9.94 1.81 2.08

[0197] Table 16

[0198] refer to Figure 1 The virtual reality system 10 provided in this application may include a first optical system 100 and a second optical system 200 in any of the above embodiments. Each embodiment of the first optical system can be combined with each embodiment of the second optical system in 12 ways, that is, the virtual reality system may have 12 examples. The virtual reality system corresponding to Example 1 includes the first optical system of Embodiment 1 and the second optical system of Embodiment 4; the virtual reality system corresponding to Example 2 includes the first optical system of Embodiment 2 and the second optical system of Embodiment 4; the virtual reality system corresponding to Example 3 includes the first optical system of Embodiment 3 and the second optical system of Embodiment 4; the virtual reality system corresponding to Example 4 includes the first optical system of Embodiment 1 and the second optical system of Embodiment 5; the virtual reality system corresponding to Example 5 includes the first optical system of Embodiment 2 and the second optical system of Embodiment 5; the virtual reality system corresponding to Example 6 includes the first optical system of Embodiment 3 and the second optical system of Embodiment 5; the virtual reality system corresponding to Example 7 includes the first optical system of Embodiment 1 and the second optical system of Embodiment 6; the virtual reality system corresponding to Example 8 includes the first optical system of Embodiment 2 and the second optical system of Embodiment 6; the virtual reality system corresponding to Example 9 includes the first optical system of Embodiment 3 and the second optical system of Embodiment 6; the virtual reality system corresponding to Example 10 includes the first optical system of Embodiment 1 and the second optical system of Embodiment 7; the virtual reality system corresponding to Example 11 includes the first optical system of Embodiment 2 and the second optical system of Embodiment 7; and the virtual reality system corresponding to Example 12 includes the first optical system of Embodiment 3 and the second optical system of Embodiment 7.

[0199] In summary, Examples 1 to 12 above satisfy the conditions shown in Tables 17-1 and 17-2, respectively.

[0200]

[0201]

[0202] Table 17-1

[0203] Conditional / Example 7 8 9 10 11 12 TD' / TD 2.19 2.15 2.15 2.24 2.20 2.20 TD' / f' 1.18 1.17 1.17 1.18 1.17 1.17 TD / f 6.73 6.73 6.73 5.67 5.67 5.67 f' / f 12.45 12.35 12.36 10.75 10.66 10.67 |(f1+f45)| / f' 0.25 0.25 0.25 0.09 0.09 0.09 FOV / FOV' 1.51 1.67 1.60 1.55 1.70 1.64 f4' / f' 1.58 1.48 1.48 1.58 1.48 1.48 TTL / f 8.59 8.59 8.59 7.39 7.39 7.39 [f1' / (V1'+VR+VQ1)+f2' / (V2'+VQ2)] / (CT1'+CT2') -0.43 -3.93 -3.94 -0.43 -3.93 -3.94 (f3'+f4') / (f3'-f4') 1.67 1.24 1.24 1.67 1.24 1.24 (R2'+R6') / (T12'×V2'+T23'×V3') -7.09 -10.24 -10.23 -7.09 -10.24 -10.23 (R7'-R8') / (f'-f4') -7.12 -6.94 -6.92 -7.12 -6.94 -6.92 f' / T01 1.15 1.14 1.12 1.15 1.14 1.12 f' / R2' -0.28 -0.27 -0.27 -0.28 -0.27 -0.27 (N1'-N2')×R2'-(N2'-N3')×R6' 11.93 15.79 15.81 11.93 15.79 15.81 f / f45 0.50 0.50 0.50 0.50 0.50 0.50 (f1+f2)×(N1+N2) / T12 -18.54 -18.54 -18.54 -14.46 -14.46 -14.46 SD / ImgH 1.43 1.43 1.43 1.21 1.21 1.21 (R1+R2) / R10 -2.80 -2.80 -2.80 -3.36 -3.36 -3.36 (CT4+CT5) / (R8+R10) -0.48 -0.48 -0.48 -0.87 -0.87 -0.87 (V1+V2)×(CT1+CT2) / f1 -22.05 -22.05 -22.05 -30.26 -30.26 -30.26 (|V2-V3|×T23) / [(V2+V3)×(CT2+CT3)] 0.92 0.92 0.92 0.00 0.00 0.00

[0204] Table 17-2

[0205] refer to Figure 1 In exemplary embodiments, the virtual reality system 10 provided in this application may further include, for example, a third optical system 300 and a fourth optical system 400. In some embodiments, the third optical system 300 and / or the fourth optical system 400 may be, for example, a second optical system 200.

[0206] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A virtual reality system, comprising a first optical system and a second optical system, characterized in that, The first optical system includes, in sequence from the first side to the second side along the first optical axis, a first element group, a second element group, a third element group, and a fourth element group. The first element group includes a first lens, a reflective polarizing element, and a first quarter-wave plate. The second element group includes a second lens and a second quarter-wave plate. The third element group includes a third lens. The fourth element group includes a fourth lens. The second optical system includes, sequentially 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, and a fifth lens; and The virtual reality system satisfies: 1.17≤TD' / f'≤1.18, 5.67≤TD / f≤7.34, and 2.0 <TD' / TD<2.4, Wherein, TD' is the axial distance from the first side of the first element group to the second side of the fourth lens, f' is the effective focal length of the first optical system, TD is the axial distance from the object side of the first lens to the image side of the fifth lens, and f is the effective focal length of the second optical system; The first optical system has four lenses with optical power. The reflective polarizing element is attached to the first side of the first quarter-wave plate, and the first quarter-wave plate is attached to the first side of the first lens; The second quarter-wave plate is attached to the first side of the second lens; The first optical system further includes a partial reflective layer attached to the second side surface of the first lens; The first side is the human eye side, and the second side is the display screen side; The first lens has positive optical power, its first side surface is a plane, and its second side surface is a convex surface; The second lens has negative optical power, its first side is a plane, and its second side is a concave surface; The third lens has positive optical power, and its first side surface is concave and its second side surface is convex. The fourth lens has positive optical power, and its first side surface is convex, and its second side surface is convex. The second optical system has five lenses with optical power. The first lens has negative optical power, and its object side is convex while its image side is concave. The second lens has negative optical power and its image side is concave. The third lens has positive optical power; The fourth and fifth lenses have opposite positive and negative optical power properties; The object side of the fourth lens is convex, and the image side of the fifth lens is convex.

2. The virtual reality system according to claim 1, characterized in that, It satisfies: 10.66≤f' / f≤13.

97.

3. The virtual reality system according to claim 1, characterized in that, The effective focal length f1 of the first lens and the combined focal length f45 of the fourth and fifth lenses satisfy: 0.09≤|(f1+f45)| / f'≤0.

57.

4. The virtual reality system according to claim 1, characterized in that, The maximum field of view (FOV) of the second optical system and the maximum field of view (FOV') of the first optical system satisfy: 1.51 ≤ FOV / FOV' ≤ 1.

70.

5. The virtual reality system according to claim 1, characterized in that, The effective focal length f4' of the fourth lens satisfies: 1.48 ≤ f4' / f' ≤ 1.58, and, The distance TTL on the axis from the object side of the first lens to the imaging surface of the second optical system satisfies: 7.39≤TTL / f≤9.

24.

6. The virtual reality system according to any one of claims 1 to 5, characterized in that, The effective focal length f3' of the third lens and the effective focal length f4' of the fourth lens satisfy the following condition: 1.24≤(f3'+f4') / (f3'-f4')≤1.

67.

7. The virtual reality system according to claim 1, characterized in that, The radius of curvature R2' of the second side surface of the first lens, the radius of curvature R6' of the second side surface of the third lens, the air gap T12' between the first element group and the second element group on the first optical axis, the dispersion coefficient V2' of the second lens, the air gap T23' between the second element group and the third element group on the first optical axis, and the dispersion coefficient V3' of the third lens satisfy: -10.24≤(R2'+R6') / (T12'×V2'+T23'×V3')≤-7.

09.

8. The virtual reality system according to any one of claims 1 to 5, characterized in that, The radius of curvature R7' of the first side surface of the fourth lens, the radius of curvature R8' of the second side surface of the fourth lens, and the effective focal length f4' of the fourth lens satisfy: -7.12≤(R7'-R8') / (f'-f4')≤-6.

92.

9. The virtual reality system according to any one of claims 1 to 5, characterized in that, The distance T01 from the first side of the first element group to the entrance pupil position of the first optical system on the first optical axis satisfies: 1.12≤f' / T01≤1.

15.

10. The virtual reality system according to any one of claims 1 to 5, characterized in that, The radius of curvature R2' of the second side surface of the first lens satisfies: -0.28≤f' / R2'≤-0.

27.

11. The virtual reality system according to any one of claims 1 to 5, characterized in that, The refractive index N1' of the first lens, the refractive index N2' of the second lens, the radius of curvature R2' of the second side surface of the first lens, the refractive index N3' of the third lens, and the radius of curvature R6' of the second side surface of the third lens satisfy: 11.93mm≤(N1'-N2')×R2'-(N2'-N3')×R6'≤15.81mm.

12. The virtual reality system according to any one of claims 1 to 5, characterized in that, The fourth lens and the fifth lens are cemented together to form a cemented lens, and the combined focal length f45 of the fourth lens and the fifth lens satisfies: 0.09≤f / f45≤0.

50.

13. The virtual reality system according to any one of claims 1 to 5, characterized in that, The axial distance SD from the aperture of the second optical system to the image side of the fifth lens satisfies the condition that half the diagonal length ImgH of the effective pixel area on the imaging surface of the second optical system is 1.21≤SD / ImgH≤1.

55.

14. The virtual reality system according to any one of claims 1 to 5, characterized in that, The radius of curvature R1 of the object side of the first lens, the radius of curvature R2 of the image side of the first lens, and the radius of curvature R10 of the image side of the fifth lens satisfy: -3.55≤(R1+R2) / R10≤-0.

95.

15. The virtual reality system according to any one of claims 1 to 5, characterized in that, The center thickness CT4 of the fourth lens on the second optical axis, the center thickness CT5 of the fifth lens on the second optical axis, the radius of curvature R8 of the image side of the fourth lens, and the radius of curvature R10 of the image side of the fifth lens satisfy: -0.87≤(CT4+CT5) / (R8+R10)≤-0.

14.

16. The virtual reality system according to any one of claims 1 to 5, characterized in that, The dispersion coefficient V1 of the first lens, the dispersion coefficient V2 of the second lens, the center thickness CT1 of the first lens on the second optical axis, the center thickness CT2 of the second lens on the second optical axis, and the effective focal length f1 of the first lens satisfy: -33.93≤(V1+V2)×(CT1+CT2) / f1≤-22.

05.

17. The virtual reality system according to claim 1, characterized in that, The dispersion coefficient V2 of the second lens, the dispersion coefficient V3 of the third lens, the air gap T23 between the second lens and the third lens on the second optical axis, the center thickness CT2 of the second lens on the second optical axis, and the center thickness CT3 of the third lens on the second optical axis satisfy: 0.00≤(|V2-V3|×T23) / [(V2+V3)×(CT2+CT3)]≤0.92.

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