Virtual reality system

Abstract

The application provides a virtual reality system. The virtual reality system comprises a first optical system and a second optical system, the first optical system comprises a first optical lens group, a second optical lens group and a third optical lens group, and the second optical system comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens; when the following conditions are met: |f2'|>|f'|, the axial distance TD' of the first side surface of the first lens of the first optical system to the second side surface of the last lens, the air interval T12' of the first lens and the second lens of the first optical system on the first optical axis and the air interval T23' of the second lens and the third lens of the first optical system on the first optical axis satisfy: 7<TD' / (T12'+T23')<12, and the effective focal length f1' of the first optical lens group of the first optical system and the effective focal length f1 of the first lens of the second optical system satisfy: -44<f1' / f1<‑26. The application solves the problems of large volume and small field of view of the perspective system in the prior art virtual reality system.

Description

TECHNICAL FIELD

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

[0002] With the development of virtual reality technology, various virtual reality display devices have entered people's lives, such as VR (Virtual Reality) head-mounted display devices. The VR head-mounted display device includes a virtual reality system for imaging display. The virtual reality system generally includes a visual system and a see-through system. The visual system can allow the user to enter the virtual world. In combination with the see-through system, the virtual world and the real world can be interacted. The see-through system mainly captures real-time images of the real world through a camera, then combines the captured images with virtual images, and finally allows the user to "see" the real world in the virtual world.

[0003] However, the current virtual reality system has some problems, such as the overall length of the virtual reality system is relatively large, which leads to a large volume and heavy weight of the VR device, and the field of view of the see-through system of the virtual reality system is relatively small, which seriously affects the user's experience.

[0004] That is, the virtual reality system in the prior art has the problems of large volume and small field of view of the see-through system. SUMMARY

[0005] The main purpose of the present application is to provide a virtual reality system to solve the problem of large volume and small field of view of the see-through system in the prior art.

[0006] To achieve the above object, according to one aspect of the present application, there is provided a virtual reality system comprising a first optical system and a second optical system cooperating with each other, wherein the first optical system comprises, in sequence along a first optical axis direction, a first lens group, a second lens group and a third lens group, the first lens group is composed of a first lens and a reflective polarizing element attached to the first lens, the second lens group is composed of a second lens and a quarter-wave plate attached to the second lens, and the third lens group is composed of a third lens; the second optical system comprises, in sequence along a second optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens; when an effective focal length f2' of the second lens group of the first optical system and an effective focal length f' of the first optical system satisfy |f2'|>|f'|, an on-axis distance TD' from a first side of the first lens of the first optical system to a second side of the last lens, an air gap T12' of the first lens and the second lens of the first optical system on the first optical axis, and an air gap T23' of the second lens and the third lens of the first optical system on the first optical axis satisfy 7<TD' / (T12'+T23')<12, and an effective focal length f1' of the first lens group of the first optical system and an effective focal length f1 of the first lens of the second optical system satisfy -44<f1' / f1<-26.

[0007] Further, the first optical system has a stop, and the stop is arranged at a first side of the first lens group.

[0008] Further, the second optical system has a stop, and the stop is arranged between the first lens and the second lens.

[0009] Further, a maximum field angle FOV of the second optical system and a maximum field angle FOV' of the first optical system satisfy 1.0<FOV / FOV'<1.2.

[0010] Further, an entrance pupil diameter EPD' of the first optical system and an entrance pupil diameter EPD of the second optical system satisfy 4.5<EPD' / EPD<6.0.

[0011] Further, a curvature radius R4' of a second side of the second lens of the second lens group and the effective focal length f2' of the second lens group of the first optical system satisfy -6.5<R4' / f2'<-2.5.

[0012] Further, the effective focal length f' of the first optical system, an effective focal length f3 of the third lens of the second optical system and an effective focal length f4 of the fourth lens of the second optical system satisfy 4.7<f' / f4+f' / f3<6.4.

[0013] Further, the effective focal length f' of the first optical system, the effective focal length f2 of the second lens of the second optical system, and the effective focal length f3 of the third lens of the second optical system satisfy: 4.8 < f' / (f2 + f3) < 6.2.

[0014] Further, the axial distance TD from the first side surface of the first lens of the second optical system to the second side surface of the last lens, and the maximum value CTmax of the central thickness of all the lenses of the second optical system on the second optical axis satisfy: 5.9 < TD / CTmax < 6.6.

[0015] Further, the effective focal length f3 of the third lens of the second optical system, the effective focal length f4 of the fourth lens of the second optical system, and the effective focal length f5 of the fifth lens of the second optical system satisfy: 0.6 < (f3 + f4) / f5 < 1.2.

[0016] Further, the central thickness CT1' of the first lens of the first optical system on the first optical axis, the central thickness CT2' of the second lens of the first optical system on the first optical axis, the Abbe number V1' of the first lens of the first optical system, and the refractive index N1' of the first lens of the first optical system satisfy: 12 < (CT1' / CT2') * (V1' / N1') < 51.

[0017] Further, the radius of curvature R4' of the second side surface of the second lens of the second lens group, and the radius of curvature R5' of the first side surface of the third lens of the first optical system satisfy: R4' / R5' < 1.0.

[0018] Further, the effective focal length f' of the first optical system, and the axial distance TD' from the first side surface of the first lens to the second side surface of the last lens of the first optical system satisfy: 0.8 < f' / TD' < 1.5.

[0019] Further, the distance SD from the diaphragm to the second side surface of the last lens of the second optical system, and the maximum value ATmax of the air gap of the adjacent two lenses on the optical axis in the second optical system satisfy: 2.3 < SD / ATmax < 3.1.

[0020] Further, the effective focal length f1 of the first lens of the second optical system, and the refractive index N1 of the first lens of the second optical system satisfy: 2.6 < |f1 / N1| < 3.3.

[0021] Further, the effective focal length f5 of the fifth lens of the second optical system, and the refractive index N5 of the fifth lens of the second optical system satisfy: 2.4 < |f5 / N5| < 3.8.

[0022] Further, an axial distance TD from a first side surface of the first lens of the second optical system to a second side surface of the last lens satisfies: 3.7 < TD / ATmax < 4.3, where ATmax is a maximum value of air intervals on the optical axis of adjacent two lenses in the second optical system.

[0023] According to another aspect of the present application, there is provided a virtual reality system including a first optical system and a second optical system cooperating with each other, wherein the first optical system sequentially includes a first lens group, a second lens group and a third lens group along a first optical axis direction, the first lens group is composed of a first lens and a reflective polarizing element attached to the first lens, the second lens group is composed of a second lens and a quarter wave plate attached to the second lens, and the third lens group is composed of a third lens; the second optical system sequentially includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens along a second optical axis; when an effective focal length f2' of the second lens group of the first optical system and an effective focal length f' of the first optical system satisfy: |f2'| > |f'|, an axial distance TD' from a first side surface of the first lens of the first optical system to a second side surface of the last lens, an air interval T12' on the first optical axis of the first lens and the second lens of the first optical system, and an air interval T23' on the first optical axis of the second lens and the third lens of the first optical system satisfy: 7 < TD' / (T12'+T23') < 12, and a maximum field angle FOV of the second optical system and a maximum field angle FOV' of the first optical system satisfy: 1.0 < FOV / FOV' < 1.2.

[0024] Further, the first optical system has a stop, and the stop is disposed at a first side of the first lens group.

[0025] Further, the second optical system has a stop, and the stop is disposed between the first lens and the second lens.

[0026] Further, an entrance pupil diameter EPD' of the first optical system and an entrance pupil diameter EPD of the second optical system satisfy: 4.5 < EPD' / EPD < 6.0.

[0027] Further, an effective focal length f1' of the first lens group of the first optical system and an effective focal length f1 of the first lens of the second optical system satisfy: -44 < f1' / f1 < -26, and a curvature radius R4' of a second side surface of the second lens of the second lens group and an effective focal length f2' of the second lens group of the first optical system satisfy: -6.5 < R4' / f2' < -2.5.

[0028] Further, the effective focal length f' of the first optical system, the effective focal length f3 of the third lens of the second optical system, and the effective focal length f4 of the fourth lens of the second optical system satisfy: 4.7 < f' / f4 + f' / f3 < 6.4.

[0029] Further, the effective focal length f' of the first optical system, the effective focal length f2 of the second lens of the second optical system, and the effective focal length f3 of the third lens of the second optical system satisfy: 4.8 < f' / f2 + f' / f3 < 6.2.

[0030] Further, the on-axis distance TD from the first side surface of the first lens to the second side surface of the last lens of the second optical system, and the maximum value CTmax of the central thickness of all the lenses of the second optical system on the second optical axis satisfy: 5.9 < TD / CTmax < 6.6.

[0031] Further, the effective focal length f3 of the third lens of the second optical system, the effective focal length f4 of the fourth lens of the second optical system, and the effective focal length f5 of the fifth lens of the second optical system satisfy: 0.6 < (f3 + f4) / f5 < 1.2.

[0032] Further, the central thickness CT1' of the first lens of the first optical system on the first optical axis, the central thickness CT2' of the second lens of the first optical system on the first optical axis, the Abbe number V1' of the first lens of the first optical system, and the refractive index N1' of the first lens of the first optical system satisfy: 12 < (CT1' / CT2') * (V1' / N1') < 51.

[0033] Further, the radius of curvature R4' of the second side surface of the second lens of the second lens group, and the radius of curvature R5' of the first side surface of the third lens of the first optical system satisfy: R4' / R5' < 1.0.

[0034] Further, the effective focal length f' of the first optical system, and the on-axis distance TD' from the first side surface of the first lens to the second side surface of the last lens of the first optical system satisfy: 0.8 < f' / TD' < 1.5.

[0035] Further, the distance SD from the stop to the second side surface of the last lens of the second optical system, and the maximum value ATmax of the air separation of the adjacent two lenses on the optical axis in the second optical system satisfy: 2.3 < SD / ATmax < 3.1.

[0036] Further, the effective focal length f1 of the first lens of the second optical system, and the refractive index N1 of the first lens of the second optical system satisfy: 2.6 < |f1 / N1| < 3.3.

[0037] Further, an effective focal length f5 of the fifth lens of the second optical system and a refractive index N5 of the fifth lens of the second optical system satisfy: 2.4 < |f5 / N5| < 3.8.

[0038] Further, an on-axis distance TD from a first side surface of the first lens of the second optical system to a second side surface of the last lens and a maximum value ATmax of air spacings of two adjacent lenses in the second optical system on the optical axis satisfy: 3.7 < TD / ATmax < 4.3.

[0039] The virtual reality system includes a first optical system and a second optical system that cooperate with each other. The first optical system includes, in sequence along a first optical axis, a first lens group, a second lens group, and a third lens group. The first lens group is composed of a first lens and a reflective polarizing element attached to the first lens. The second lens group is composed of a second lens and a quarter-wave plate attached to the second lens. The third lens group is composed of a third lens. The second optical system includes, in sequence along a second optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens. When an effective focal length f2' of the second lens group of the first optical system and an effective focal length f' of the first optical system satisfy: |f2'| > |f'|, an on-axis distance TD' from a first side surface of the first lens of the first optical system to a second side surface of the last lens, air spacings T12' of the first lens and the second lens of the first optical system on the first optical axis, and air spacings T23' of the second lens and the third lens of the first optical system on the first optical axis satisfy: 7 < TD' / (T12'+T23') < 12. An effective focal length f1' of the first lens group of the first optical system and an effective focal length f1 of the first lens of the second optical system satisfy: -44 < f1' / f1 < -26.

[0040] The first optical system and the second optical system are used in cooperation, in the application, the first optical system is a visual system, and the second optical system is a perspective system. The first optical system is composed of three lenses, by pasting a reflective polarizing element on the first lens of the first optical system and pasting a quarter-wave plate on the second lens, the refraction and reflection of the light path can be realized, the length of the light path is shortened, thereby the overall length of the first optical system is compressed, the small size of the virtual reality system is realized, and miniaturization is realized. The second optical system is composed of six lenses, by controlling the above conditional formula, the optical power of the first lens of the second optical system is ensured to be negative, which is beneficial to increase the field of view angle of the system. In addition, by controlling the above conditional formula, the optical power of each lens of the first optical system and the second optical system is reasonably distributed, which is beneficial to improve the aberration of the system; at the same time, the air gap between the adjacent lenses of the first optical system and the axial distance from the first side of the first lens to the second side of the last lens are controlled, which is beneficial to shorten the total length of the first optical system and make the virtual reality system light and thin; in addition, the focal length of the first optical system is controlled, so that the effective focal length of the first optical system is small, thereby the field of view angle of the first optical system is increased, which is beneficial to increase the user's immersive experience. BRIEF DESCRIPTION OF DRAWINGS

[0041] The drawings accompanying the specification of this application form a part thereof, serve to provide further understanding of the application, and together with the description of the exemplary embodiments of the application given below, make an explanation of the application, and do not constitute an improper limitation of the application. In the drawings:

[0042] Figure 1 A schematic view of the first optical system and the second optical system of the virtual reality system of an optional embodiment of the application applied in a head-mounted device is shown;

[0043] Figure 2 An enlarged view of the head-mounted device in Figure 1 is shown;

[0044] Figure 3 A structural schematic view of the first optical system of embodiment one is shown;

[0045] Figures 4 to 6 Axial chromatic aberration curves, astigmatism curves and distortion curves of the first optical system in Figure 3 are respectively shown;

[0046] Figure 7 A structural schematic view of the first optical system of embodiment two is shown;

[0047] Figures 8 to 10 Axial chromatic aberration curves, astigmatism curves and distortion curves of the first optical system in Figure 7 are respectively shown;

[0048] Figure 11A structural schematic diagram of the first optical system of Embodiment Three is shown;

[0049] Figures 12 to 14 On-axis chromatic aberration curves, astigmatism curves, distortion curves of the first optical system in Embodiment Three are shown respectively; Figure 11

[0050] Figure 15 A structural schematic diagram of the second optical system of Embodiment Four is shown;

[0051] Figures 16 to 18 On-axis chromatic aberration curves, astigmatism curves, distortion curves of the second optical system in Embodiment Four are shown respectively; Figure 15

[0052] Figure 19 A structural schematic diagram of the second optical system of Embodiment Four is shown;

[0053] Figures 20 to 22 On-axis chromatic aberration curves, astigmatism curves, distortion curves of the second optical system in Embodiment Four are shown respectively; Figure 19

[0054] A structural schematic diagram of the second optical system of Embodiment Four is shown; Figure 23

[0055] On-axis chromatic aberration curves, astigmatism curves, distortion curves of the second optical system in Embodiment Four are shown respectively. Figures 24 to 26 DETAILED DESCRIPTION Figure 23 It should be noted that the embodiments and features of the embodiments in the present application can be combined with each other without conflict, unless otherwise specified. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0056] It should be noted that, unless otherwise specified, all technical and scientific terms used in the present application have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs.

[0057] It should be noted that, unless otherwise specified, all technical and scientific terms used in the present application have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs.

[0058] In the present application, unless otherwise specified, the orientation words such as "up, down, top, bottom" are generally directed to the directions shown in the drawings, or are directed to the vertical, perpendicular or gravity directions of the components themselves; similarly, for the convenience of understanding and description, "inner, outer" refers to the inner and outer relative to the contour of the components themselves, but the above orientation words are not used to limit the present application.

[0059] It should be noted that, in the present specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, the first lens discussed below can also be referred to as the second lens or the third lens without departing from the teachings of the present application.​​​

[0060] In the drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shape of the spherical or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical or aspherical surface is not limited to the shape of the spherical or aspherical surface shown in the drawings. The drawings are merely examples and are not strictly drawn to scale.

[0061] In this document, the paraxial region refers to a region near the optical axis. If the lens surface is convex and the position of the convex surface is not specified, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not specified, it means that the lens surface is concave at least in the paraxial region. The surface of each lens near the first side is the first side surface of the lens, and the surface of each lens near the second side is the second side surface of the lens. The judgment of the surface shape in the paraxial region can be based on the judgment method of those skilled in the art, with the R value (R refers to the radius of curvature in the paraxial region, usually refers to the R value on the lens data in the optical software) to judge the convexity and concavity. In terms of the first side surface, when the R value is positive, it is determined to be convex, and when the R value is negative, it is determined to be concave; in terms of the second side surface, when the R value is positive, it is determined to be concave, and when the R value is negative, it is determined to be convex.

[0062] It should be noted that the left side of the first optical system is the first side, and the right side is the second side. The first side of the first optical system is the human eye side, and the second side is the display side. The image emitted by the display side is imaged on the human eye side. The left side of the second optical system is the first side, and the right side is the second side. The first side of the second optical system is the object side, and the second side is the image side.

[0063] In order to solve the problems of large volume and small field of view of the perspective system in the prior art, a virtual reality system is provided.

[0064] As Figures 1 to 26 shown, in an optional embodiment of the present application.

[0065] The virtual reality system comprises a first optical system and a second optical system which cooperate with each other, wherein the first optical system comprises, in sequence along a first optical axis direction, a first lens group, a second lens group and a third lens group, the first lens group is composed of a first lens and a reflective polarizing element attached to the first lens, the second lens group is composed of a second lens and a quarter-wave plate attached to the second lens, and the third lens group is composed of a third lens; the second optical system comprises, in sequence along a second optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens; when an effective focal length f2' of the second lens group of the first optical system and an effective focal length f' of the first optical system satisfy |f2'|>|f'|, an on-axis distance TD' from a first side of the first lens of the first optical system to a second side of the last lens, an air gap T12' of the first lens and the second lens of the first optical system on the first optical axis, and an air gap T23' of the second lens and the third lens of the first optical system on the first optical axis satisfy 7<TD' / (T12'+T23')<12, and an effective focal length f1' of the first lens group of the first optical system and an effective focal length f1 of the first lens of the second optical system satisfy -44<f1' / f1<-26.

[0066] The first optical system and the second optical system are used in cooperation, in the present application, the first optical system is a visual system, and the second optical system is a see-through system. The first optical system is composed of three lenses, the light path is refracted and reflected by attaching a reflective polarizing element to the first lens and a quarter-wave plate to the second lens of the first optical system, the length of the light path is shortened, thereby the overall length of the first optical system is compressed, the small size of the virtual reality system is realized, and miniaturization is achieved. The second optical system is composed of six lenses, by controlling the above condition formula, the optical power of the first lens of the second optical system is ensured to be negative, which is conducive to increasing the field of view angle of the system. In addition, by controlling the above condition formula, the optical power of each lens of the first optical system and the second optical system is reasonably distributed, which is conducive to improving the aberration of the system; at the same time, the air gap between the adjacent lenses of the first optical system and the on-axis distance from the first side of the first lens to the second side of the last lens are controlled, which is conducive to shortening the total length of the first optical system and making the virtual reality system light and thin; in addition, the focal length of the first optical system is controlled, so that the effective focal length of the first optical system is small, thereby the field of view angle of the first optical system is increased, which is conducive to increasing the immersive experience of the user.

[0067] In the present embodiment, the first optical system has a diaphragm which is arranged at the first side of the first lens group. By arranging the diaphragm at the first side of the first lens group, the converging imaging of the imaging light at the first side is facilitated.

[0068] In the embodiment, the second optical system has an aperture stop, which is arranged between the first lens and the second lens. By arranging the aperture stop between the first lens and the second lens close to the first side, the convergence of the light rays is facilitated, and the light ray trend is adjusted, and the smoothness of the light ray trend is facilitated.

[0069] It should be noted that the reflective polarizing element described above can be arranged on the first side of the first lens or on the second side of the first lens, and can be arranged according to actual conditions. The quarter-wave plate described above can be arranged on the first side of the second lens or on the second side of the second lens, and can be arranged according to actual conditions.

[0070] In the embodiment, the maximum field of view FOV of the second optical system and the maximum field of view FOV' of the first optical system satisfy: 1.0 < FOV / FOV' < 1.2. By controlling the ratio between the maximum field of view FOV of the second optical system and the maximum field of view FOV' of the first optical system, the maximum field of view of the second optical system is greater than the maximum field of view of the first optical system, which facilitates increasing the maximum field of view of the second optical system, so that the user can see a wider real world.

[0071] In the embodiment, the entrance pupil diameter EPD' of the first optical system and the entrance pupil diameter EPD of the second optical system satisfy: 4.5 < EPD' / EPD < 6.0. By controlling the ratio between the entrance pupil diameter of the first optical system and the entrance pupil diameter of the second optical system, the entrance pupil diameter of the first optical system is greater than the entrance pupil diameter of the second optical system, which facilitates increasing the luminous flux of the first optical system, thereby increasing the brightness of the image.

[0072] In the embodiment, the curvature radius R4' of the second side of the second lens of the second lens group and the effective focal length f2' of the second lens group of the first optical system satisfy: -6.5 < R4' / f2' < -2.5. By controlling the ratio between the curvature radius of the second side of the second lens of the first optical system and the effective focal length of the second lens group of the first optical system, the shape of the second lens is reasonably controlled, which facilitates the forming and processing of the second lens, and at the same time makes the curvature of the second lens smaller, which facilitates the attachment of the quarter-wave plate.

[0073] In the embodiment, the effective focal length f' of the first optical system, the effective focal length f3 of the third lens of the second optical system, and the effective focal length f4 of the fourth lens of the second optical system satisfy: 4.7 < f' / f4 + f' / f3 < 6.4. Satisfying this condition formula reasonably distributes the optical power, so that the effective focal length of the first optical system is larger, and the effective focal length of the second optical system is smaller, which controls the screen size of the first optical system while controlling the field of view of the second optical system.

[0074] In the embodiment, the effective focal length f' of the first optical system, the effective focal length f2 of the second lens of the second optical system, and the effective focal length f3 of the third lens of the second optical system satisfy 4.8 < f' / (f2 + f3) < 6.2. Satisfying the condition, the height of the light ray passing through the reflective polarizing element in the first optical system is compressed, which is conducive to reducing the size of the screen, reducing the weight of the head-mounted device, and realizing miniaturization; the height of the light ray passing through the second lens and the third lens in the second optical system is increased, which meets the requirement of CRA.

[0075] In the embodiment, the axial distance TD from the first side of the first lens of the second optical system to the second side of the last lens, and the maximum value CTmax of the center thickness of all the lenses of the second optical system on the second optical axis satisfy 5.9 < TD / CTmax < 6.6. Satisfying the condition is conducive to the molding of each lens of the second optical system and ensures the machinability of the lens.

[0076] In the embodiment, the effective focal length f3 of the third lens of the second optical system, the effective focal length f4 of the fourth lens of the second optical system, and the effective focal length f5 of the fifth lens of the second optical system satisfy 0.6 < (f3 + f4) / f5 < 1.2. Satisfying the condition reasonably distributes the refractive power of the three lenses, makes the refractive power of the fourth lens positive, converges the light rays of the outer field of view, and is conducive to reducing the size of the chip.

[0077] In the embodiment, the center thickness CT1' of the first lens of the first optical system on the first optical axis, the center thickness CT2' of the second lens of the first optical system on the first optical axis, the Abbe number V1' of the first lens of the first optical system, and the refractive index N1' of the first lens of the first optical system satisfy 12 < (CT1' / CT2') * (V1' / N1') < 51. Satisfying the condition makes the center thickness of the first lens and the second lens in the first optical system smaller, reduces the total length of the system, and is conducive to the thinness of the head-mounted device; in addition, controlling the Abbe number and the refractive index of the first lens can reduce the chromatic aberration of the system, thereby improving the imaging quality.

[0078] In the embodiment, the radius of curvature R4' of the second side of the second lens of the second lens group and the radius of curvature R5' of the first side of the third lens of the first optical system satisfy R4' / R5' < 1.0. Satisfying the condition is conducive to the attachment of the quarter-wave plate on the one hand, reduces the difficulty of the process, and on the other hand, controls the refraction angle of the light ray, reduces the height of the light ray, thereby reducing the size of the screen and being conducive to reducing the weight of the device.

[0079] In the embodiment, the effective focal length f' of the first optical system and the on-axis distance TD' from the first side surface of the first lens to the second side surface of the last lens of the first optical system satisfy: 0.8 < f' / TD' < 1.5. Satisfying the condition formula makes the effective focal length of the first optical system decrease, the system more compact, and the miniaturization of the virtual reality system beneficial.

[0080] In the embodiment, the distance SD from the stop to the second side surface of the last lens of the second optical system and the maximum value ATmax of the air gap on the optical axis of the adjacent two lenses in the second optical system satisfy: 2.3 < SD / ATmax < 3.1. Controlling the condition formula makes the arrangement of each lens of the second optical system more compact, thereby shortening the total length of the second optical system, and the overall arrangement beneficial.

[0081] In the embodiment, the effective focal length f1 of the first lens of the second optical system and the refractive index N1 of the first lens of the second optical system satisfy: 2.6 < |f1 / N1| < 3.3. Satisfying the condition formula can control the refraction angle of light passing through the first lens, which is beneficial to the convergence of the outer field of view light, thereby improving the imaging quality.

[0082] In the embodiment, the effective focal length f5 of the fifth lens of the second optical system and the refractive index N5 of the fifth lens of the second optical system satisfy: 2.4 < |f5 / N5| < 3.8. By controlling the condition formula, the power of the fifth lens of the second optical system is negative, and the positive spherical aberration generated by the negative power lens can balance the negative spherical aberration generated by other lenses, which is beneficial to reducing the spherical aberration of the system and improving the imaging quality.

[0083] In the embodiment, the on-axis distance TD from the first side surface of the first lens to the second side surface of the last lens of the second optical system and the maximum value ATmax of the air gap on the optical axis of the adjacent two lenses in the second optical system satisfy: 3.7 < TD / ATmax < 4.3. By controlling the condition formula, the center thickness of each lens in the second optical system is reasonably distributed, the moldability and processability of each lens are ensured, in addition, the length of the system is shortened, which is beneficial to the miniaturization of the second optical system, thereby reducing the size of the chip.

[0084] As shown in FIG. 1, in one optional embodiment of the present application. Figures 1 to 26

[0085] ​The virtual reality system comprises a first optical system and a second optical system which cooperate with each other, wherein the first optical system comprises, in sequence along a first optical axis direction, a first lens group, a second lens group and a third lens group, the first lens group is composed of a first lens and a reflective polarizing element attached to the first lens, the second lens group is composed of a second lens and a quarter-wave plate attached to the second lens, and the third lens group is composed of a third lens; the second optical system comprises, in sequence along a second optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens; when an effective focal length f2' of the second lens group of the first optical system and an effective focal length f' of the first optical system satisfy |f2'|>|f'|, an on-axis distance TD' from a first side of the first lens of the first optical system to a second side of the last lens, an air gap T12' of the first lens and the second lens of the first optical system on the first optical axis, and an air gap T23' of the second lens and the third lens of the first optical system on the first optical axis satisfy 7<TD' / (T12'+T23')<12, and a maximum field of view FOV of the second optical system and a maximum field of view FOV' of the first optical system satisfy 1.0<FOV / FOV'<1.2.

[0086] The first optical system and the second optical system are used in cooperation, in the present application, the first optical system is a visual system, and the second optical system is a see-through system. The first optical system is composed of three lenses, the reflective polarizing element is attached to the first lens of the first optical system, and the quarter-wave plate is attached to the second lens, so that the refraction and reflection of the light path are realized, the length of the light path is shortened, the overall length of the first optical system is compressed, the small size of the virtual reality system is realized, and miniaturization is realized. The second optical system is composed of six lenses, by controlling the above condition formula, the refractive power of the first lens of the second optical system is ensured to be negative, which is beneficial to increase the field of view angle of the system. At the same time, the air gap and the distance of the first optical system are beneficial to shorten the total length of the first optical system, realize the miniaturization of the first optical system, and make the virtual reality system meet the light and thin requirements; by controlling the ratio between the maximum field of view FOV of the second optical system and the maximum field of view FOV' of the first optical system, the maximum field of view of the second optical system is greater than the maximum field of view of the first optical system, which is beneficial to increase the maximum field of view of the second optical system, and the user can see a wider real world.

[0087] In the present embodiment, the first optical system has a diaphragm, and the diaphragm is arranged at the first side of the first lens group. By arranging the diaphragm at the first side of the first lens group, the converging imaging of the imaging light at the first side is facilitated.

[0088] In the embodiment, the second optical system has a diaphragm, and the diaphragm is arranged between the first lens and the second lens. By arranging the diaphragm between the first lens and the second lens close to the first side, the convergence of the light rays is facilitated, and the light ray trend is adjusted, and the stability of the light ray trend is facilitated.

[0089] It should be noted that the reflective polarizing element described above can be arranged on the first side of the first lens or on the second side of the first lens, and can be arranged according to actual conditions. The quarter-wave plate described above can be arranged on the first side of the second lens or on the second side of the second lens, and can be arranged according to actual conditions.

[0090] In the embodiment, the entrance pupil diameter EPD' of the first optical system and the entrance pupil diameter EPD of the second optical system satisfy: 4.5 < EPD' / EPD < 6.0. By controlling the ratio between the entrance pupil diameter of the first optical system and the entrance pupil diameter of the second optical system, the entrance pupil diameter of the first optical system is greater than the entrance pupil diameter of the second optical system, which is conducive to increasing the luminous flux of the first optical system, thereby increasing the brightness of the image.

[0091] In the embodiment, the effective focal length f1' of the first lens group of the first optical system and the effective focal length f1 of the first lens of the second optical system satisfy: -44 < f1' / f1 < -26. By controlling the ratio between the effective focal length of the first lens group of the first optical system and the effective focal length of the second lens of the second optical system, the effective focal length of the first optical system is smaller, thereby increasing the field of view angle of the first optical system, which is conducive to increasing the immersive experience of the user.

[0092] In the embodiment, the curvature radius R4' of the second side of the second lens of the second lens group and the effective focal length f2' of the second lens group of the first optical system satisfy: -6.5 < R4' / f2' < -2.5. By controlling the ratio between the curvature radius of the second side of the second lens of the first optical system and the effective focal length of the second lens group of the first optical system, the shape of the second lens is reasonably controlled, which is conducive to the molding and processing of the second lens, and at the same time the curvature of the second lens is smaller, which is conducive to the attachment of the quarter-wave plate.

[0093] In the embodiment, the effective focal length f' of the first optical system, the effective focal length f3 of the third lens of the second optical system, and the effective focal length f4 of the fourth lens of the second optical system satisfy: 4.7 < f' / f4 + f' / f3 < 6.4. Satisfying this condition formula reasonably allocates the optical power, so that the effective focal length of the first optical system is larger, and the effective focal length of the second optical system is smaller, thereby controlling the screen size of the first optical system while controlling the field of view of the second optical system.

[0094] In the embodiment, the effective focal length f' of the first optical system, the effective focal length f2 of the second lens of the second optical system, and the effective focal length f3 of the third lens of the second optical system satisfy 4.8 < f' / (f2 + f3) < 6.2. Satisfying the condition, the height of the light ray passing through the reflective polarizing element in the first optical system is compressed, which is conducive to reducing the size of the screen, reducing the weight of the head-mounted device, and realizing miniaturization; the height of the light ray passing through the second lens and the third lens in the second optical system is increased, which meets the requirement of CRA.

[0095] In the embodiment, the axial distance TD from the first side of the first lens of the second optical system to the second side of the last lens, and the maximum value CTmax of the center thickness of all the lenses of the second optical system on the second optical axis satisfy 5.9 < TD / CTmax < 6.6. Satisfying the condition is conducive to the molding of each lens of the second optical system and ensures the machinability of the lens.

[0096] In the embodiment, the effective focal length f3 of the third lens of the second optical system, the effective focal length f4 of the fourth lens of the second optical system, and the effective focal length f5 of the fifth lens of the second optical system satisfy 0.6 < (f3 + f4) / f5 < 1.2. Satisfying the condition reasonably distributes the refractive power of the three lenses, makes the refractive power of the fourth lens positive, converges the light rays of the outer field of view, and is conducive to reducing the size of the chip.

[0097] In the embodiment, the center thickness CT1' of the first lens of the first optical system on the first optical axis, the center thickness CT2' of the second lens of the first optical system on the first optical axis, the Abbe number V1' of the first lens of the first optical system, and the refractive index N1' of the first lens of the first optical system satisfy 12 < (CT1' / CT2') * (V1' / N1') < 51. Satisfying the condition makes the center thickness of the first lens and the second lens in the first optical system smaller, reduces the total length of the system, and is conducive to the thinness of the head-mounted device; in addition, controlling the Abbe number and the refractive index of the first lens can reduce the chromatic aberration of the system, thereby improving the imaging quality.

[0098] In the embodiment, the radius of curvature R4' of the second side of the second lens of the second lens group and the radius of curvature R5' of the first side of the third lens of the first optical system satisfy R4' / R5' < 1.0. Satisfying the condition is conducive to the attachment of the quarter-wave plate on the one hand, reduces the difficulty of the process, and on the other hand, controls the refraction angle of the light ray, reduces the height of the light ray, thereby reducing the size of the screen and being conducive to reducing the weight of the device.

[0099] In the embodiment, the effective focal length f' of the first optical system and the on-axis distance TD' from the first side surface of the first lens to the second side surface of the last lens of the first optical system satisfy: 0.8 < f' / TD' < 1.5. Satisfying the condition formula makes the effective focal length of the first optical system decrease, the system is more compact, and the miniaturization of the virtual reality system is facilitated.

[0100] In the embodiment, the distance SD from the stop to the second side surface of the last lens of the second optical system and the maximum value ATmax of the air gap on the optical axis of the adjacent two lenses in the second optical system satisfy: 2.3 < SD / ATmax < 3.1. Controlling the condition formula makes the arrangement of each lens of the second optical system more compact, thereby shortening the total length of the second optical system, and facilitating the overall arrangement.

[0101] In the embodiment, the effective focal length f1 of the first lens of the second optical system and the refractive index N1 of the first lens of the second optical system satisfy: 2.6 < |f1 / N1| < 3.3. Satisfying the condition formula can control the refraction angle of light passing through the first lens, facilitate the convergence of the outer field of view light, and thereby improve the imaging quality.

[0102] In the embodiment, the effective focal length f5 of the fifth lens of the second optical system and the refractive index N5 of the fifth lens of the second optical system satisfy: 2.4 < |f5 / N5| < 3.8. By controlling the condition formula, the power of the fifth lens of the second optical system is negative, and the positive spherical aberration generated by the negative power lens can balance the negative spherical aberration generated by other lenses, thereby reducing the spherical aberration of the system and improving the imaging quality.

[0103] In the embodiment, the on-axis distance TD from the first side surface of the first lens to the second side surface of the last lens of the second optical system and the maximum value ATmax of the air gap on the optical axis of the adjacent two lenses in the second optical system satisfy: 3.7 < TD / ATmax < 4.3. By controlling the condition formula, the center thickness of each lens in the second optical system is reasonably distributed, the moldability and processability of each lens are ensured, in addition, the length of the system is shortened, the miniaturization of the second optical system is facilitated, and thereby the size of the chip is reduced.

[0104] Of course, in the specific embodiments of the present application, the second optical system further includes a flat glass, and the flat glass is arranged between the first lens and the second lens of the second optical system.

[0105] Optionally, the first optical system and the second optical system of the virtual reality system described above can further comprise a filter for correcting color deviation and / or a protective glass for protecting the photosensitive elements located on the imaging surface. By reasonably setting the first optical system and the second optical system, the virtual reality system of the present application can be applied in a head-mounted or portable VR device.

[0106] In the present application, at least one of the surfaces of each lens is an aspheric mirror surface. The aspheric lens has the characteristic that the curvature continuously changes from the center of the lens to the periphery of the lens. Unlike a spherical lens which has a constant curvature from the center of the lens to the periphery of the lens, the aspheric lens has a better curvature radius characteristic, which has the advantages of improving the distortion aberration and improving the astigmatism aberration. After using the aspheric lens, the aberration that occurs during imaging can be eliminated as much as possible, thereby improving the imaging quality.

[0107] Since the aspheric surface is obtained by rotating a meridional surface around the optical axis for one revolution, the structure has rotational symmetry, and in an ideal optical system, the aberrations of the meridional surface and the sagittal surface can be well corrected; at the same time, due to its unique lens model, it can provide sufficient space for subsequent related adjustment, making the related structure and assembly process more flexible and not reducing too much imaging quality.

[0108] However, those skilled in the art should understand that the number of lenses constituting the virtual reality system can be changed without departing from the technical solutions claimed by the present application, to obtain the various results and advantages described in the present specification. For example, although the first optical system is described by taking three lenses as an example in the embodiments, and the second optical system is described by taking six lenses as an example, the virtual reality system is not limited to comprising the above number of lenses. If necessary, the virtual reality system can further comprise other number of lenses.

[0109] The specific surface type and parameters of the first optical system and the second optical system of the virtual reality system applicable to the above embodiments will be further described below with reference to the accompanying drawings.

[0110] It should be noted that any one of the following embodiments 1 to 6 is applicable to all embodiments of the present application. Embodiments 1 to 3 describe the first optical system of the virtual reality system, and embodiments 4 to 6 describe the second optical system of the virtual reality system, wherein any one of the first optical systems in embodiments 1 to 3 can be used in combination with any one of the second optical systems in embodiments 4 to 6.

[0111] As Figure 1The diagram shows the relative positions of the first optical system 10 and the second optical system 20 of the virtual reality system of this application in a head-mounted device. Of course, the virtual reality system of this application is not limited to just the two systems, the first optical system 10 and the second optical system 20; that is, the virtual reality system of this application can have three, four, or more systems. Figure 2 As shown, Figure 1 An enlarged view of the head-mounted device. Figures 3 to 14 Three embodiments of the first optical system 10 are described. Figures 15 to 26 Three embodiments of the second optical system 20 are described.

[0112] Example 1

[0113] like Figures 3 to 6 As shown, a first optical system 10 of a virtual reality system according to an embodiment of this application is described. Figure 1 The optical path diagram of the first optical system 10 in Embodiment 1 is shown.

[0114] like Figure 3 As shown, the first optical system 10 of the virtual reality system includes, from the first side to the second side, an aperture stop STO, a first lens E1, a reflective polarizing element RP, a second lens E2, a quarter-wave plate QWP1, a third lens E3, and a light-emitting surface S9 of the display. The reflective polarizing element RP is attached to the second side surface S2 of the first lens, and the quarter-wave plate QWP1 is attached to the second side surface S5 of the second lens.

[0115] The first lens E1 has positive optical power, its first side surface S1 is convex, and its second side surface S2 is flat. The second lens E2 has positive optical power, its first side surface S4 is convex, and its second side surface S5 is convex. The third lens E3 has positive optical power, its first side surface S7 is concave, and its second side surface S8 is convex.

[0116] In this embodiment, the total effective focal length f' of the first optical system 10 is 21.38 mm, the focal length f1' of the first lens group is 167.95 mm, the focal length f2' of the second lens group is 22.38 mm, the focal length f3' of the third lens group is 272.11 mm, the maximum field of view FOV' of the first optical system 10 is 90.00°, and the entrance pupil diameter EPD' of the first optical system 10 is 5.25 mm.

[0117] Combining Table 1 and Figure 3, the light emitted by the light emitting surface S9 of the display of the first optical system 10 of the embodiment one sequentially passes through the third lens E3, the quarter wave plate QWP1, the second lens E2, and is incident on the second side surface S3 of the reflective polarizing element, and a first reflection occurs. The light of the first reflection sequentially passes through the second lens E2, the quarter wave plate QWP1, the first side surface S7 of the third lens, and is incident on the second side surface S8 of the third lens, and a second reflection occurs. The reflected light sequentially passes through the first side surface S7 of the third lens, the quarter wave plate QWP1, the second lens E2, the reflective polarizing element RP, and the first lens E1, and reaches the stop STO. Since the reflective polarizing element RP is attached to the second side surface S2 of the first lens, the second side surface S2 of the first lens and the first side surface S2 of the reflective polarizing element are the same surface, and S3 is the second side surface of the reflective polarizing element. Since the quarter wave plate QWP1 is attached to the second side surface S5 of the second lens, the second side surface S5 of the second lens and the first side surface S5 of the quarter wave plate are the same surface, and S6 is the second side surface of the quarter wave plate.

[0118] Table 1 shows a basic structure parameter table of the virtual reality system of the embodiment one, wherein the units of the radius of curvature and the thickness are millimeters (mm).

[0119]

[0120] Table 1

[0121] In the embodiment one, the first side surface S1 of the first lens, the two side surfaces of the second lens, and the two side surfaces of the third lens are all aspherical surfaces. The surface type of each aspherical lens can be defined by, but not limited to, the following aspherical formula:

[0122] Formula (1);

[0123] wherein x is the distance from the vertex of the aspherical surface when the aspherical surface is at a height of h along the optical axis, h is the height, c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the inverse of the radius of curvature R in Table 1 above), k is the conic coefficient, and Ai is the correction coefficient of the i-th order of the aspherical surface. Table 2 below shows the high-order coefficient A4, A6, A8, A10 of each aspherical surface S1-S8 that can be used in the embodiment one.

[0124]

[0125] Table 2

[0126] Figure 4 Figure 6 shows the on-axis chromatic aberration curve of the first optical system 10 of the virtual reality system of the embodiment one, which represents the deviation of the converging focus points of light rays of different wavelengths after passing through the first optical system 10. Figure 5An astigmatism curve of the first optical system 10 of the virtual reality system of embodiment one is shown, which represents the meridional image surface curvature and sagittal image surface curvature. Figure 6 A distortion curve of the first optical system 10 of the virtual reality system of embodiment one is shown, which represents the distortion size values corresponding to different field angles.

[0127] According to Figures 4 to 6 It can be known that the first optical system 10 given by embodiment one can achieve good imaging quality.

[0128] Embodiment two

[0129] As Figures 7 to 10 shown, the first optical system 10 of the virtual reality system of embodiment two of the present application is described. Figure 7 A light path trend chart of the first optical system 10 of embodiment two is shown.

[0130] As Figure 7 shown, the first optical system 10 of the virtual reality system sequentially includes a stop STO, a reflective polarizing element RP, a first lens E1, a quarter-wave plate QWP1, a second lens E2, a third lens E3, and a light-emitting surface S9 of a display from the first side to the second side. The reflective polarizing element RP is attached to the first side surface S2 of the first lens, and the quarter-wave plate QWP1 is attached to the first side surface S5 of the second lens.

[0131] The first lens E1 has a positive focal power, the first side surface S2 of the first lens is a plane, and the second side surface S3 of the first lens is a convex surface. The second lens E2 has a positive focal power, the first side surface S5 of the second lens is a concave surface, and the second side surface S6 of the second lens is a convex surface. The third lens E3 has a positive focal power, the first side surface S7 of the third lens is a concave surface, and the second side surface S8 of the third lens is a convex surface.

[0132] In the present embodiment, the total effective focal length f' of the first optical system 10 is 20.02 mm, the focal length f1' of the first lens group is 176.72 mm, the focal length f2' of the second lens group is 21.68 mm, the focal length f3' of the third lens group is 150.91 mm, the maximum field angle FOV' of the first optical system 10 is 90.00°, and the entrance pupil diameter EPD' of the first optical system 10 is 4.90 mm.

[0133] In combination with Table 3 and Figure 7The light emitted from the light emitting surface S9 of the display of the first optical system 10 of Embodiment Two successively passes through the third lens E3, the second lens E2, the quarter wave plate QWP1, the first lens E1, and then is incident on the second side surface S2 of the reflective polarizing element, and a first reflection occurs. The light of the first reflection successively passes through the second side surface S3 of the first lens, the quarter wave plate QWP1, the second lens E2, the first side surface S7 of the third lens, and then is incident on the second side surface S8 of the third lens, and a second reflection occurs. The light of the second reflection successively passes through the first side surface S7 of the third lens, the second lens E2, the quarter wave plate QWP1, the first lens E1, and the reflective polarizing element RP, and then reaches the stop STO. Since the reflective polarizing element RP is attached to the first side surface S2 of the first lens, the first side surface S2 of the first lens and the second side surface S2 of the reflective polarizing element are the same surface, and S1 is the first side surface of the reflective polarizing element. Since the quarter wave plate QWP1 is attached to the first side surface S5 of the second lens, the first side surface S5 of the second lens and the second side surface S5 of the quarter wave plate are the same surface, and S4 is the first side surface of the quarter wave plate.

[0134] Table 3 shows a basic structure parameter table of the virtual reality system of Embodiment Two, wherein the units of the radius of curvature and the thickness are millimeters (mm).

[0135]

[0136] Table 3

[0137] Table 4 shows the high-order term coefficients of the aspherical mirrors that can be used in Embodiment Two, wherein each aspherical surface type can be defined by the formula (1) given in Embodiment One.

[0138]

[0139] Table 4

[0140] Figure 8 Figure 9 shows the axial chromatic aberration curve of the first optical system 10 of the virtual reality system of Embodiment Two, which represents the deviation of the converging focal points of light rays of different wavelengths after passing through the first optical system 10. Figure 9 Figure 10 shows the astigmatism curve of the first optical system 10 of the virtual reality system of Embodiment Two, which represents the meridional image curvature and the sagittal image curvature. Figure 10 Figure 11 shows the distortion curve of the first optical system 10 of the virtual reality system of Embodiment Two, which represents the distortion size values corresponding to different field angles.

[0141] According to Figures 8 to 10 It can be seen that the first optical system 10 given in Embodiment Two can achieve good imaging quality.

[0142] Embodiment Three

[0143] like Figures 11 to 14 As shown, the first optical system 10 of the virtual reality system of Embodiment 3 of this application is described. Figure 11 The optical path diagram of the first optical system 10 in Embodiment 3 is shown.

[0144] like Figure 11 As shown, the first optical system 10 of the virtual reality system includes, from the first side to the second side, an aperture stop STO, a first lens E1, a reflective polarizing element RP, a second lens E2, a quarter-wave plate QWP1, a third lens E3, and a light-emitting surface S9 of the display. The reflective polarizing element RP is attached to the second side surface S2 of the first lens, and the quarter-wave plate QWP1 is attached to the second side surface S5 of the second lens.

[0145] The first lens E1 has positive optical power, its first side surface S1 is convex, and its second side surface S2 is flat. The second lens E2 has positive optical power, its first side surface S4 is convex, and its second side surface S5 is convex. The third lens E3 has positive optical power, its first side surface S7 is concave, and its second side surface S8 is convex.

[0146] In this embodiment, the total effective focal length f' of the first optical system 10 is 19.24 mm, the focal length f1' of the first lens group is 135.78 mm, the focal length f2' of the second lens group is 19.48 mm, the focal length f3' of the third lens group is -144.89 mm, the maximum field of view FOV' of the first optical system 10 is 90.00°, and the entrance pupil diameter EPD' of the first optical system 10 is 4.90 mm.

[0147] Combined with Table 5 and Figure 11 In Embodiment 3, the light emitted from the light-emitting surface S9 of the first optical system 10 passes sequentially through the third lens E3, the quarter-wave plate QWP1, and the second lens E2 before entering the second side surface S3 of the reflective polarizing element, resulting in a first reflection. The first reflected light then passes sequentially through the second lens E2 and the quarter-wave plate QWP1 before entering the first side surface S7 of the third lens, resulting in a second reflection. The second reflected light then passes sequentially through the quarter-wave plate QWP1, the second lens E2, the reflective polarizing element RP, and the first lens E1 before reaching the aperture stop STO. Since the reflective polarizing element RP is attached to the second side surface S2 of the first lens, the second side surface S2 of the first lens and the first side surface S2 of the reflective polarizing element are on the same surface, and S3 is the second side surface of the reflective polarizing element. Since the quarter-wave plate QWP1 is attached to the second side surface S5 of the second lens, the second side surface S5 of the second lens and the first side surface S5 of the quarter-wave plate are on the same surface, and S6 is the second side surface of the quarter-wave plate.

[0148] Table 5 shows a basic structure parameter table of the virtual reality system of Example Three, wherein the units of the radius of curvature and the thickness are millimeters (mm).

[0149]

[0150] Table 5

[0151] Table 6 shows the high-order term coefficients of each aspherical mirror surface that can be used in Example Three, wherein each aspherical surface type can be defined by the formula (1) given in Example One above.

[0152]

[0153] Table 6

[0154] Figure 12 Figure 8 shows the on-axis chromatic aberration curve of the first optical system 10 of the virtual reality system of Example Three, which represents the convergence focus deviation of light rays of different wavelengths after passing through the first optical system 10. Figure 13 Figure 9 shows the astigmatism curve of the first optical system 10 of the virtual reality system of Example Three, which represents the meridional image surface curvature and sagittal image surface curvature. Figure 14 Figure 10 shows the distortion curve of the first optical system 10 of the virtual reality system of Example Three, which represents the distortion size values corresponding to different field angles.

[0155] According to Figures 12 to 14 It can be seen that the first optical system 10 given in Example Three can achieve good imaging quality.

[0156] Example Four

[0157] As Figures 15 to 18 shown, the second optical system 20 of the virtual reality system of Example Four is described. Figure 15 Figure 11 shows a structural schematic diagram of the second optical system 20 of Example Four.

[0158] As Figure 15 shown, the second optical system 20 of the virtual reality system sequentially includes, from the first side to the second side, a first lens E1, a flat glass T, a stop STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a protective glass E7, and an imaging surface S15.

[0159] The first lens E1 has a negative focal power, the first side surface S1 of the first lens is concave, and the second side surface S2 of the first lens is convex. The second lens E2 has a positive focal power, the first side surface S3 of the second lens is convex, and the second side surface S4 of the second lens is convex. The third lens E3 has a negative focal power, the first side surface S5 of the third lens is convex, and the second side surface S6 of the third lens is concave. The fourth lens E4 has a positive focal power, the first side surface S7 of the fourth lens is convex, and the second side surface S8 of the fourth lens is convex. The fifth lens E5 has a negative focal power, the first side surface S9 of the fifth lens is convex, and the second side surface S10 of the fifth lens is concave. The sixth lens E6 has a negative focal power, the first side surface S11 of the sixth lens is convex, and the second side surface S12 of the sixth lens is concave. The protective glass E7 has a first side surface S13 of the protective glass and a second side surface S14 of the protective glass. Light from an object sequentially passes through each surface S1 to S14 and is finally imaged on an imaging surface S15.

[0160] In the present embodiment, the total track length TTL of the second optical system 20 is 5.02 mm, the image height ImgH of the second optical system 20 is 2.15 mm, the maximum field of view FOV of the second optical system 20 is 102.87°, the aperture value Fno of the second optical system 20 is 2.22, the total effective focal length f of the second optical system 20 is 2.01 mm, the focal length f1 of the first lens of the second optical system 20 is -4.07 mm, the focal length f2 of the second lens of the second optical system 20 is 2.25 mm, the focal length f3 of the third lens of the second optical system 20 is -6.47 mm, the focal length f4 of the fourth lens of the second optical system 20 is 2.23 mm, the focal length f5 of the fifth lens of the second optical system 20 is -4.46 mm, and the focal length f6 of the sixth lens of the second optical system 20 is -29.21 mm.

[0161] Table 7 shows a basic structure parameter table of the virtual reality system of Embodiment Four, wherein the units of the curvature radius and the thickness are millimeters (mm).

[0162]

[0163] Table 7

[0164] Table 8 shows the high-order term coefficients of the aspherical mirrors that can be used in Embodiment Four, wherein each aspherical surface type can be defined by the formula (1) given in Embodiment One.

[0165]

[0166] Table 8

[0167] Figure 16An on-axis chromatic aberration curve of the second optical system 20 of the virtual reality system of embodiment four is shown, which represents the convergence point deviation of light rays of different wavelengths after passing through the second optical system 20. Figure 17 An astigmatism curve of the second optical system 20 of the virtual reality system of embodiment four is shown, which represents the meridional image surface curvature and sagittal image surface curvature. Figure 18 A distortion curve of the second optical system 20 of the virtual reality system of embodiment four is shown, which represents the distortion size values corresponding to different field angles.

[0168] According to Figures 16 to 18 It can be seen that the second optical system 20 given in embodiment four can achieve good imaging quality.

[0169] Embodiment five

[0170] As Figures 19 to 22 shown, the second optical system 20 of the virtual reality system of embodiment five of the present application is described. Figure 19 A structural schematic diagram of the second optical system 20 of embodiment five is shown.

[0171] As Figure 19 shown, the second optical system 20 of the virtual reality system sequentially includes a first lens E1, a flat glass T, a diaphragm STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a protective glass E7, and an imaging surface S15 from the first side to the second side.

[0172] The first lens E1 has a negative optical power, the first side surface S1 of the first lens is concave, and the second side surface S2 of the first lens is convex. The second lens E2 has a positive optical power, the first side surface S3 of the second lens is convex, and the second side surface S4 of the second lens is convex. The third lens E3 has a negative optical power, the first side surface S5 of the third lens is convex, and the second side surface S6 of the third lens is concave. The fourth lens E4 has a positive optical power, the first side surface S7 of the fourth lens is convex, and the second side surface S8 of the fourth lens is convex. The fifth lens E5 has a negative optical power, the first side surface S9 of the fifth lens is convex, and the second side surface S10 of the fifth lens is concave. The sixth lens E6 has a positive optical power, the first side surface S11 of the sixth lens is convex, and the second side surface S12 of the sixth lens is concave. The protective glass E7 has a first side surface S13 of the protective glass and a second side surface S14 of the protective glass. Light from the object sequentially passes through each surface S1 to S14 and is finally imaged on the imaging surface S15.

[0173] In the embodiment, the total track length TTL of the second optical system 20 is 5.55 mm, the image height ImgH of the second optical system 20 is 2.26 mm, the maximum field of view FOV of the second optical system 20 is 97.98°, the aperture value Fno of the second optical system 20 is 2.22, the total effective focal length f of the second optical system 20 is 2.23 mm, the focal length f1 of the first lens of the second optical system 20 is -5.08 mm, the focal length f2 of the second lens of the second optical system 20 is 2.56 mm, the focal length f3 of the third lens of the second optical system 20 is -7.14 mm, the focal length f4 of the fourth lens of the second optical system 20 is 2.54 mm, the focal length f5 of the fifth lens of the second optical system 20 is -4.08 mm, and the focal length f6 of the sixth lens of the second optical system 20 is 36.99 mm.

[0174] Table 9 shows a basic structure parameter table of the virtual reality system of Embodiment Five, wherein the units of the curvature radius and the thickness are millimeters (mm).

[0175]

[0176] Table 9

[0177] Table 10 shows high-order term coefficients of each aspherical mirror surface that can be used in Embodiment Five, wherein each aspherical surface type can be defined by the formula (1) given in Embodiment One.

[0178]

[0179] Table 10

[0180] Figure 20 Figure 9 shows an axial chromatic aberration curve of the second optical system 20 of the virtual reality system of Embodiment Five, which represents the convergence focus deviation of light rays of different wavelengths after passing through the second optical system 20. Figure 21 Figure 10 shows a stigmation curve of the second optical system 20 of the virtual reality system of Embodiment Five, which represents the meridional image surface curvature and sagittal image surface curvature. Figure 22 Figure 11 shows a distortion curve of the second optical system 20 of the virtual reality system of Embodiment Five, which represents the distortion size values corresponding to different field angles.

[0181] According to Figures 20 to 22 It can be known that the second optical system 20 given in Embodiment Five can achieve good imaging quality.

[0182] Embodiment Six

[0183] As Figures 23 to 26 shown, the second optical system 20 of the virtual reality system of Embodiment Six of the present application is described. Figure 23 Figure 12 shows a structure schematic diagram of the second optical system 20 of Embodiment Six.

[0184] like Figure 23 As shown, the second optical system 20 of the virtual reality system includes, from the first side to the second side, a first lens E1, a flat glass T, an aperture STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a protective glass E7, and an imaging surface S15.

[0185] The first lens E1 has negative optical power, its first side surface S1 is concave, and its second side surface S2 is convex. The second lens E2 has positive optical power, its first side surface S3 is convex, and its second side surface S4 is convex. The third lens E3 has negative optical power, its first side surface S5 is convex, and its second side surface S6 is concave. The fourth lens E4 has positive optical power, its first side surface S7 is convex, and its second side surface S8 is convex. The fifth lens E5 has negative optical power, its first side surface S9 is convex, and its second side surface S10 is concave. The sixth lens E6 has negative optical power, its first side surface S11 is convex, and its second side surface S12 is concave. The protective glass E7 has a first side surface S13 and a second side surface S14. Light from the object passes sequentially through surfaces S1 to S14 and is finally imaged on the imaging surface S15.

[0186] In this embodiment, the total optical length (TTL) of the second optical system 20 is 5.20 mm, the image height (ImgH) of the second optical system 20 is 2.31 mm, the maximum field of view (FOV) of the second optical system 20 is 102.00°, the aperture value (Fno) of the second optical system 20 is 2.22, the total effective focal length (f) of the second optical system 20 is 2.29 mm, the focal length (f1) of the first lens of the second optical system 20 is -4.75 mm, the focal length (f2) of the second lens of the second optical system 20 is 2.44 mm, the focal length (f3) of the third lens of the second optical system 20 is -6.49 mm, the focal length (f4) of the fourth lens of the second optical system 20 is 2.31 mm, the focal length (f5) of the fifth lens of the second optical system 20 is -6.18 mm, and the focal length (f6) of the sixth lens of the second optical system 20 is -5.29 mm.

[0187] Table 11 shows the basic structural parameters of the virtual reality system in Embodiment 6, where the units for radius of curvature and thickness are millimeters (mm).

[0188]

[0189] Table 11

[0190] Table 12 shows the high-order term coefficients of each aspherical mirror surface used in Example 6, wherein each aspherical surface type can be defined by the formula (1) given in Example 1 above.

[0191]

[0192] Table 12

[0193] Figure 24 Figure 12 shows the axial chromatic aberration curve of the second optical system 20 of the virtual reality system of Example 6, which represents the deviation of the converging focal points of light rays of different wavelengths after passing through the second optical system 20. Figure 25 Figure 13 shows the astigmatism curve of the second optical system 20 of the virtual reality system of Example 6, which represents the meridional image curvature and sagittal image curvature. Figure 26 Figure 14 shows the distortion curve of the second optical system 20 of the virtual reality system of Example 6, which represents the distortion size values corresponding to different field angles.

[0194] According to Figures 24 to 26 It can be seen that the second optical system 20 given in Example 6 can achieve good imaging quality.

[0195] In summary, the virtual reality system provided in the present application can be composed of any one of the first optical systems 10 in Example 1 to Example 3 and any one of the second optical systems 20 in Example 4 to Example 6, and each combination of the first optical system 10 and the second optical system 20 can form 9 virtual reality systems. Among them, referring to Table 13, the virtual reality system corresponding to Example Combination 1 is composed of the first optical system 10 of Example 1 and the second optical system 20 of Example 4, the virtual reality system corresponding to Example Combination 2 is composed of the first optical system 10 of Example 1 and the second optical system 20 of Example 5, the virtual reality system corresponding to Example Combination 3 is composed of the first optical system 10 of Example 1 and the second optical system 20 of Example 6, the virtual reality system corresponding to Example Combination 4 is composed of the first optical system 10 of Example 2 and the second optical system 20 of Example 4, the virtual reality system corresponding to Example Combination 5 is composed of the first optical system 10 of Example 2 and the second optical system 20 of Example 5, the virtual reality system corresponding to Example Combination 6 is composed of the first optical system 10 of Example 2 and the second optical system 20 of Example 6, the virtual reality system corresponding to Example Combination 7 is composed of the first optical system 10 of Example 3 and the second optical system 20 of Example 4, the virtual reality system corresponding to Example Combination 8 is composed of the first optical system 10 of Example 3 and the second optical system 20 of Example 5, and the virtual reality system corresponding to Example Combination 9 is composed of the first optical system 10 of Example 3 and the second optical system 20 of Example 6.

[0196]

[0197] Table 13

[0198] The present application also provides an imaging device, the electronic photosensitive element of which can be a charge-coupled device (CCD) or a complementary metal-oxide-semiconductor device (CMOS). The imaging device can be a standalone imaging apparatus such as a digital camera, or an imaging module integrated on a mobile electronic device such as a mobile phone. The imaging device is equipped with the virtual reality system described above.

[0199] Obviously, the above-described embodiments are only some, but not all of the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative work should fall within the protection scope of the present application.

[0200] It is to be noted that the terms used herein are only used to describe specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form, unless the context clearly indicates otherwise, and it should also be understood that the terms "comprise" and / or "include" as used in the specification, indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0201] It should be noted that the terms "first", "second", and the like in the description and claims of the present application and above-described accompanying drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0202] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A virtual reality system, characterized by The first optical system and the second optical system are cooperated with each other, wherein The first optical system comprises, in sequence along the first optical axis, a first lens group with positive refractive power, a second lens group with positive refractive power and a third lens group with positive refractive power, the first lens group is composed of a first lens and a reflective polarizing element attached to the first lens, the second lens group is composed of a second lens and a quarter-wave plate attached to the second lens, and the third lens group is composed of a third lens; the total number of lenses with refractive power in the first optical system is 3; the first lens of the first optical system has positive refractive power, the first side thereof is a convex surface, and the second side thereof is a plane; or the first side thereof is a plane, and the second side thereof is a convex surface; the second lens of the first optical system has positive refractive power, the first side thereof is a convex surface or a concave surface, and the second side thereof is a convex surface; and the third lens of the first optical system has positive refractive power, the first side thereof is a concave surface, and the second side thereof is a convex surface; The second optical system comprises, in sequence along the second optical axis, a first lens with negative refractive power, a second lens with positive refractive power, a third lens with negative refractive power, a fourth lens with positive refractive power, a fifth lens with negative refractive power and a sixth lens; the total number of lenses with refractive power in the second optical system is 6; The first lens of the second optical system has negative refractive power, the first side thereof is a concave surface, and the second side thereof is a convex surface; the second lens of the second optical system has positive refractive power, the first side thereof is a convex surface, and the second side thereof is a convex surface; the third lens of the second optical system has negative refractive power, the first side thereof is a convex surface, and the second side thereof is a concave surface; the fourth lens of the second optical system has positive refractive power, the first side thereof is a convex surface, and the second side thereof is a convex surface; the fifth lens of the second optical system has negative refractive power, the first side thereof is a convex surface, and the second side thereof is a concave surface; and the first side of the sixth lens of the second optical system is a convex surface, and the second side thereof is a concave surface; The effective focal length f2' of the second lens group of the first optical system and the effective focal length f' of the first optical system satisfy |f2'|>|f'|, the on-axis distance TD' from the first side of the first lens of the first optical system to the second side of the last lens, the air gap T12' of the first lens and the second lens of the first optical system along the first optical axis, and the air gap T23' of the second lens and the third lens of the first optical system along the first optical axis satisfy 7.69≤TD' / (T12'+T23')≤11.17, and the effective focal length f1' of the first lens group of the first optical system and the effective focal length f1 of the first lens of the second optical system satisfy -43.43≤f1' / f1≤-26.

72.

2. The virtual reality system of claim 1, wherein, The first optical system has a diaphragm, which is arranged on the first side of the first lens group.

3. The virtual reality system of claim 1, wherein, The second optical system has a diaphragm, which is arranged between the first lens and the second lens.

4. The virtual reality system of claim 1, wherein, The maximum field angle FOV of the second optical system and the maximum field angle FOV' of the first optical system satisfy: 1.09≤FOV / FOV'≤1.

14.

5. The virtual reality system of claim 1, wherein, The entrance pupil diameter EPD' of the first optical system and the entrance pupil diameter EPD of the second optical system satisfy: 4.74≤EPD' / EPD≤5.

79.

6. The virtual reality system of claim 1, wherein, The radius of curvature R4' of the second side surface of the second lens of the second lens group and the effective focal length f2' of the second lens group of the first optical system satisfy: -6.44≤R4' / f2'≤-2.

68.

7. The virtual reality system of claim 1, wherein, The effective focal length f' of the first optical system, the effective focal length f3 of the third lens of the second optical system, and the effective focal length f4 of the fourth lens of the second optical system satisfy: 4.88≤f' / f4+f' / f3≤6.

28.

8. The virtual reality system of claim 1, wherein, The effective focal length f' of the first optical system, the effective focal length f2 of the second lens of the second optical system, and the effective focal length f3 of the third lens of the second optical system satisfy: 4.8<f' / f2+f' / f3<6.

2.

9. The virtual reality system of any of claims 1 to 8, wherein, The on-axis distance TD from the first side surface of the first lens to the second side surface of the last lens of the second optical system and the maximum value CTmax of the central thickness of all lenses of the second optical system on the second optical axis satisfy: 5.95≤TD / CTmax<6.

6.

10. The virtual reality system of any one of claims 1 to 8, wherein, The effective focal length f3 of the third lens of the second optical system, the effective focal length f4 of the fourth lens of the second optical system, and the effective focal length f5 of the fifth lens of the second optical system satisfy: 0.68≤(f3+f4) / f5≤1.

13.

11. The virtual reality system of any one of claims 1 to 8, wherein, The central thickness CT1' of the first lens of the first optical system on the first optical axis, the central thickness CT2' of the second lens of the first optical system on the first optical axis, the Abbe number V1' of the first lens of the first optical system, and the refractive index N1' of the first lens of the first optical system satisfy: 12.20≤(CT1' / CT2')*(V1' / N1')≤50.

56.

12. The virtual reality system of any one of claims 1 to 8, wherein, The radius of curvature R4' of the second side surface of the second lens of the second lens group and the radius of curvature R5' of the first side surface of the third lens of the first optical system satisfy: 0.05≤R4' / R5'≤0.

72.

13. The virtual reality system of any one of claims 1 to 8, wherein, The effective focal length f' of the first optical system and the on-axis distance TD' from the first side surface of the first lens to the second side surface of the last lens of the first optical system satisfy: 0.97≤f' / TD'≤1.

42.

14. The virtual reality system of any one of claims 1 to 8, wherein, The distance SD from the stop to the second side surface of the last lens of the second optical system and the maximum value ATmax of the air separation of two adjacent lenses on the optical axis in the second optical system satisfy: 2.38≤SD / ATmax<3.

1.

15. The virtual reality system of any one of claims 1 to 8, wherein, An effective focal length f1 of the first lens of the second optical system and a refractive index N1 of the first lens of the second optical system satisfy: 2.6 < |f1 / N1| < 3.

3.

16. The virtual reality system of any one of claims 1 to 8, wherein, An effective focal length f5 of the fifth lens of the second optical system and a refractive index N5 of the fifth lens of the second optical system satisfy: 2.4 < |f5 / N5| ≤ 3.

71.

17. The virtual reality system of any one of claims 1 to 8, wherein, An on-axis distance TD from a first side surface of the first lens to a second side surface of the last lens of the second optical system and a maximum value ATmax of air spacings on the optical axis of two adjacent lenses in the second optical system satisfy: 3.7 < TD / ATmax < 4.3.

Images