Visual system and VR device comprising the same

Abstract

The application discloses a visual system, comprising a lens barrel and a first element group and a second element group arranged in sequence from a first side to a second side along an optical axis in the lens barrel, wherein the first element group has positive focal power and comprises a first lens, a reflective polarizing element, a quarter-wave plate and a second lens; the second element group has negative focal power and comprises a third lens; and a first spacing element is arranged between the first lens and the second lens. An effective focal length FG1 of the first element group, an effective focal length FG2 of the second element group, an inner diameter d1m of a second side surface of the first spacing element and an outer diameter D1m of the second side surface of the first spacing element satisfy a condition formula: 0.5<|FG1+FG2| / (d1m+D1m)<2.5.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical elements, and more particularly to a visual system and a VR device comprising the same. BACKGROUND

[0002] Since the concept of "meta universe" was proposed, AR (Augmented Reality) / VR (Virtual Reality) has ushered in a second opportunity for development. As an entry for human-computer interaction, the VR imaging lens plays an important role. On the one hand, the imaging quality of the VR imaging lens needs to meet the resolution requirements of the human eye; on the other hand, the early aspheric or Fresnel lens body is relatively long, and when the user experiences it, the center of gravity of the device is forward, and the experience is not good, which needs to be improved.

[0003] Based on the above needs, a folding scheme is proposed, which can significantly compress the length of the lens body by light path folding, for example, to half of the original, so as to move the center of gravity of the display device backward and improve the experience of consumers. However, for the current optical system based on light path folding, the compactness of the structure and the system imaging quality still need to be further improved. Therefore, how to more reasonably design each lens and the spacing element therebetween to improve the compactness, stability and processability of the lens is one of the technical problems that the technical personnel in the current field need to solve. SUMMARY

[0004] The present application provides a visual system, which can include a lens barrel and a first element group and a second element group assembled in the lens barrel and arranged in order from a first side to a second side along an optical axis, wherein the first element group has a positive focal power and includes a first lens, a reflective polarizing element, a quarter-wave plate and a second lens; the second element group has a negative focal power and includes a third lens; the first lens and the second lens have a first spacing element therebetween; the effective focal length FG1 of the first element group, the effective focal length FG2 of the second element group, the inner diameter d1m of the second side of the first spacing element and the outer diameter D1m of the second side of the first spacing element can satisfy: 0.5 < |FG1 + FG2| / (d1m + D1m) < 2.5.

[0005] In one embodiment, the radius of curvature R3 of the first side of the second lens, the radius of curvature R4 of the second side of the second lens, the inner diameter d1s of the first side of the first spacing element and the outer diameter D1s of the first side of the first spacing element can satisfy: 0.6 < (R3 + R4) / (d1s + D1s) < 1.8.

[0006] In one embodiment, the outer diameter D0s of the first side end surface of the lens barrel, the inner diameter d0s of the first side end surface of the lens barrel, and the entrance pupil diameter EPD of the visual system can satisfy: 5 < (D0s - d0s) / EPD < 6.

[0007] In one embodiment, the effective focal length f of the visual system, the distance EP01 from the first side end surface of the lens barrel to the first side surface of the first spacer element along the optical axis, and the maximum thickness CP1 of the first spacer element along the direction of the optical axis can satisfy: 3 < f / (EP01 + CP1) < 4.5.

[0008] In one embodiment, the inner diameter d1s of the first side surface of the first spacer element, the central thickness CT1 of the first lens along the optical axis, the central thickness CTR of the reflective polarizing element along the optical axis, and the central thickness CTQ of the quarter-wave plate along the optical axis can satisfy: 19 < d1s / (CT1 + CTR + CTQ) < 22.

[0009] In one embodiment, the inner diameter d0m of the second side end surface of the lens barrel and the distance TD from the first side surface of the first lens to the second side surface of the third lens along the optical axis can satisfy: 2.9 < d0m / TD < 4.9.

[0010] In one embodiment, the distance L from the first side end surface of the lens barrel to the second side end surface of the lens barrel along the optical axis, the central thickness CT1 of the first lens along the optical axis, the central thickness CT2 of the second lens along the optical axis, and the central thickness CT3 of the third lens along the optical axis can satisfy: 1 < L / (CT1 + CT2 + CT3) < 2.

[0011] In one embodiment, the radius of curvature R5 of the first side surface of the third lens and the maximum outer diameter D0max of the lens barrel and the minimum inner diameter d0min of the lens barrel can satisfy: 3.5 < |R5| / (D0max - d0min) < 4.5.

[0012] In one embodiment, the minimum inner diameter d1min of the first spacer element, the distance T12 from the second side surface of the first lens to the first side surface of the second lens along the optical axis, and the distance T23 from the second side surface of the second lens to the first side surface of the third lens along the optical axis can satisfy: 34 < d1min / (T12 + T23) < 43.

[0013] In one embodiment, the radius of curvature R1 of the first side surface of the first lens and the maximum outer diameter D1max of the first spacer element can satisfy: 3.5 < R1 / D1max < 12.5.

[0014] In one embodiment, the inner diameter dOm of the second side end face of the lens barrel and the outer diameter DOm of the second side end face of the lens barrel can satisfy: 0.7<|FG2| / (dOm+D0m)<2.2.

[0015] In one embodiment, the effective focal length f of the visual system, the entrance pupil diameter EPD of the visual system, the distance L of the first side end face of the lens barrel to the second side end face of the lens barrel along the optical axis, and the distance EP01 of the first side end face of the lens barrel to the first side face of the first spacer element along the optical axis can satisfy: 26<(f / EPD) x (L / EP01)<41.

[0016] In another aspect, the present application also provides a VR device, which can include the visual system provided in any of the above embodiments.

[0017] The visual system disclosed in the present application includes a first element group and a second element group arranged in sequence from a first side to a second side along an optical axis in a lens barrel, wherein the first element group has a positive focal power and includes a first lens, a reflective polarizing element, a quarter-wave plate, and a second lens; the second element group has a negative focal power and includes a third lens; a first spacer element is arranged between the first lens and the second lens; and the effective focal length FG1 of the first element group, the effective focal length FG2 of the second element group, the inner diameter d1m of the second side face of the first spacer element, and the outer diameter D1m of the second side face of the first spacer element satisfy the condition formula 0.5<|FG1+FG2| / (d1m+D1m)<2.5. The arrangement of the visual system disclosed in the present application can limit the outer shape of the first lens, the second lens, and the third lens, support the structure of the first lens and the second lens by the first spacer element, and be conducive to realizing the compactness of the lens structure and improving the processability. BRIEF DESCRIPTION OF DRAWINGS

[0018] Other features, objects, and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments, taken in conjunction with the accompanying drawings. In the drawings:

[0019] Figure 1 The structure and part of the parameters of the visual system according to the exemplary embodiments of the present application are shown;

[0020] Figure 2 、 Figure 3 and Figure 4 The structure schematic diagrams of the visual system according to the embodiment 1 of the present application in three embodiments are shown respectively;

[0021] Figure 5 、 Figure 6 andFigure 7 On-axis chromatic aberration curves, astigmatism curves and distortion curves of the visual system of Example 1 are shown in FIGS. 1A, 1B and 1C, respectively;

[0022] Figure 8 Figure 9 and Figure 10 Structure diagrams of the visual system according to Example 2 of the present application in three implementation manners are shown in FIGS. 2A, 2B and 2C, respectively;

[0023] Figure 11 Figure 12 and Figure 13 On-axis chromatic aberration curves, astigmatism curves and distortion curves of the visual system of Example 2 are shown in FIGS. 4A, 4B and 4C, respectively;

[0024] Figure 14 Figure 15 and Figure 16 Structure diagrams of the visual system according to Example 3 of the present application in three implementation manners are shown in FIGS. 5A, 5B and 5C, respectively; and

[0025] Figure 17 Figure 18 and Figure 19 On-axis chromatic aberration curves, astigmatism curves and distortion curves of the visual system of Example 3 are shown in FIGS. 7A, 7B and 7C, respectively. DETAILED DESCRIPTION

[0026] For a better understanding of the present application, various aspects of the present application will be described in greater detail below with reference to the accompanying drawings. It is to be understood that the detailed description is merely descriptive of exemplary embodiments of the present application and is not intended to limit the scope of the present application in any way. Throughout the specification, like reference numerals refer to like elements. The expression “and / or” includes any and all combinations of one or more of the associated listed items.

[0027] It should be noted that, in the present specification, the expressions first, second, third and the like are merely used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, the first lens discussed below can also be referred to as the second lens or the third lens without departing from the teachings of the present application.

[0028] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shape of the spherical surface or the aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical surface or the aspherical surface is not limited to the shape of the spherical surface or the aspherical surface shown in the drawings. The drawings are merely examples and are not drawn strictly to scale.

[0029] ​​​​In this context, the paraxial region refers to a region near the optical axis. If a lens surface is convex and the position of the convex surface is not specified, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the position of the concave surface is not specified, it means that the lens surface is concave at least in the paraxial region.

[0030] It should also be understood that the use of the terms "including", "comprising", "having" and / or "containing" when used in this specification, specifies the presence of stated features, elements and / or components, but do not preclude the presence or addition of one or more other features, elements, components and / or groups thereof. Furthermore, as used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. In addition, expressions such as "at least one of...", when preceding a list of two or more items, denote that at least one of each item in the list is present, but does not exclude the presence of all of the items or the addition of one or more items. Furthermore, as used herein, the use of "a" and / or "an" includes singular and plural references unless the context clearly indicates otherwise. Also, as used herein, the use of "or" as a conjunction, permits a full range of one or the other, as well as both or neither one or the other. Also, as used herein, the use of "comprise", "comprises" or "comprising" will be understood to enable the presence of a stated feature, element, component, function or the like but does not preclude the presence or addition of one or more other features, elements, components, functions or the like.

[0031] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0032] It should be noted that the embodiments and features of the embodiments in the present application can be combined with each other without conflict. The following embodiments only express several implementation manners of the present application, which are described in a more specific and detailed manner, but should not be understood as a limitation on the patent scope of the present application. It should be pointed out that, for those skilled in the art, some modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0033] The features, principles, and other aspects of the present application are described in detail below.

[0034] The visual system according to the exemplary embodiments of the present application can include a lens barrel and a lens group assembled in the lens barrel, and the lens group can include a first element group and a second element group arranged in order from a first side to a second side along an optical axis.

[0035] In the exemplary embodiments, the first element group can have a positive refractive power. The first element group can include a first lens, a reflective polarizing element, a quarter wave plate, and a second lens.

[0036] In an example embodiment, the second element group can have negative optical power. The second element group can include a third lens.

[0037] In an example embodiment, the visual system can further include a first spacer element located between the first lens and the second lens.

[0038] In an example embodiment, the visual system of the present application can satisfy the condition 0.5<|FG1+FG2| / (d1m+D1m)<2.5, where FG1 is the effective focal length of the first element group, FG2 is the effective focal length of the second element group, d1m is the inner diameter of the second side surface of the first spacer element, and D1m is the outer diameter of the second side surface of the first spacer element. It is understood that the surface of each element closer to the first side and farther from the second side is the first side surface of the element, and the surface of each element closer to the second side and farther from the first side is the second side surface of the element.

[0039] The visual system according to an example embodiment of the present application includes a first element group and a second element group arranged in sequence along an optical axis from a first side to a second side in a lens barrel, wherein the first element group has positive optical power and includes a first lens, a reflective polarizing element, a quarter-wave plate, and a second lens; the second element group has negative optical power and includes a third lens; a first spacer element is provided between the first lens and the second lens; and the effective focal length FG1 of the first element group, the effective focal length FG2 of the second element group, the inner diameter d1m of the second side surface of the first spacer element, and the outer diameter D1m of the second side surface of the first spacer element satisfy the condition 0.5<|FG1+FG2| / (d1m+D1m)<2.5. Through such a configuration of the visual system, the outer shape of the first lens, the second lens, and the third lens can be limited, the support of the first spacer element to the structure of the first lens and the second lens can be satisfied, and the compactness of the lens structure and the machinability can be improved.

[0040] In an example embodiment, the first side can be, for example, an eye side, and the second side can be, for example, a display side. The visual system can be used, for example, in various VR display devices.

[0041] In exemplary embodiments, the visual system of the present application can satisfy the condition formula 0.6 < (R3+R4) / (d1s+D1s) < 1.8, wherein R3 is the radius of curvature of the first side of the second lens, R4 is the radius of curvature of the second side of the second lens, d1s is the inner diameter of the first side of the first spacer element, and D1s is the outer diameter of the first side of the first spacer element. By controlling the ratio of the sum of the radius of curvature of the first side of the second lens and the radius of curvature of the second side of the second lens to the sum of the inner diameter of the first side of the first spacer element and the outer diameter of the first side of the first spacer element within this range, the maximum outer shape of the lens barrel can be limited, which is conducive to achieving the compactness of the lens structure, while being conducive to correcting the off-axis aberration and improving the overall image quality of the system.

[0042] In exemplary embodiments, the visual system of the present application can satisfy the condition formula 5 < (D0s-d0s) / EPD < 6, wherein D0s is the outer diameter of the first side end surface of the lens barrel (i.e., the end surface or surface of the lens barrel closest to the first side), d0s is the inner diameter of the first side end surface of the lens barrel, and EPD is the entrance pupil diameter of the visual system. By controlling the ratio of the difference between the outer diameter of the first side end surface of the lens barrel and the inner diameter of the first side end surface of the lens barrel to the entrance pupil diameter of the visual system within this range, the lens barrel diameter and the lens diameter are maintained in a certain proportion, and the uniformity of the lens barrel wall thickness is conducive to stabilizing the reliability of the lens.

[0043] In exemplary embodiments, the visual system of the present application can satisfy the condition formula 3 < f / (EP01+CP1) < 4.5, wherein f is the effective focal length of the visual system, EP01 is the distance along the optical axis from the first side end surface of the lens barrel to the first side of the first spacer element, and CP1 is the maximum thickness of the first spacer element in the direction along the optical axis or parallel to the optical axis. By controlling the ratio of the effective focal length of the visual system to the sum of the distance along the optical axis from the first side end surface of the lens barrel to the first side of the first spacer element and the maximum thickness of the first spacer element in the direction along the optical axis within this range, the lens barrel end surface wall thickness and the first spacer element structure diameter thickness can be reasonably controlled, which is conducive to the molding of the lens barrel and the lens.

[0044] In exemplary embodiments, the visual system of the present application can satisfy the condition formula 19 < d1s / (CT1+CTR+CTQ) < 22, wherein d1s is the inner diameter of the first side of the first spacer element, CT1 is the center thickness of the first lens on the optical axis, CTR is the center thickness of the reflective polarizing element on the optical axis, and CTQ is the center thickness of the quarter-wave plate on the optical axis. By controlling the ratio of the inner diameter of the first side of the first spacer element to the sum of the center thickness of the first lens on the optical axis, the center thickness of the reflective polarizing element on the optical axis, and the center thickness of the quarter-wave plate on the optical axis within this range, the chromatic aberration of the optical system can be corrected, and the wearing experience of consumers can be improved.

[0045] In an example embodiment, the visual system of the present application can satisfy condition formula 2.9 < d0m / TD < 4.9, wherein d0m is the inner diameter of the second side end face of the lens barrel (i.e., the end face or surface of the lens barrel closest to the second side), and TD is the distance on the optical axis from the first side face of the first lens to the second side face of the third lens. By controlling the ratio of the inner diameter of the second side end face of the lens barrel to the distance on the optical axis from the first side face of the first lens to the second side face of the third lens to be within this range, a compact design of the optical system can be achieved.

[0046] In an example embodiment, the visual system of the present application can satisfy condition formula 1 < L / (CT1+CT2+CT3) < 2, wherein L is the distance on the optical axis from the first side end face of the lens barrel to the second side end face of the lens barrel, CT1 is the central thickness on the optical axis of the first lens, CT2 is the central thickness on the optical axis of the second lens, and CT3 is the central thickness on the optical axis of the third lens. By controlling the ratio of the distance on the optical axis from the first side end face of the lens barrel to the second side end face of the lens barrel to the sum of the central thickness on the optical axis of the first lens, the central thickness on the optical axis of the second lens, and the central thickness on the optical axis of the third lens to be within this range, a compact design of the system is facilitated, while the layout of the second and third lenses is also facilitated, the tolerances in the assembly process of the second and third lenses are reasonably allocated, and the processability of the lens is effectively improved.

[0047] In an example embodiment, the visual system of the present application can satisfy condition formula 3.5 < |R5| / (D0max-d0min) < 4.5, wherein R5 is the radius of curvature of the first side face of the third lens, D0max is the maximum outer diameter of the lens barrel, and d0min is the minimum inner diameter of the lens barrel. By controlling the radius of curvature of the first side face of the third lens, the maximum outer diameter of the lens barrel, and the minimum inner diameter of the lens barrel to satisfy condition formula 3.5 < |R5| / (D0max-d0min) < 4.5, the maximum outer shape of the lens barrel can be limited, a compact design of the lens structure is facilitated, while off-axis aberrations are also corrected, and the overall image quality of the system is improved.

[0048] In an example embodiment, the visual system of the present application can satisfy condition formula 34 < d1min / (T12+T23) < 43, wherein d1min is the minimum inner diameter of the first spacer element, T12 is the air gap on the optical axis between the first lens and the second lens, i.e., the distance on the optical axis from the second side face of the first lens to the first side face of the second lens, and T23 is the air gap on the optical axis between the second lens and the third lens, i.e., the distance on the optical axis from the second side face of the second lens to the first side face of the third lens. By controlling the ratio of the minimum inner diameter of the first spacer element to the sum of the air gap on the optical axis between the first lens and the second lens and the air gap on the optical axis between the second lens and the third lens to be within this range, the air gaps between the lenses can be compressed as much as possible on the basis of ensuring the overall image quality of the system, thereby reducing the overall size of the system.

[0049] In an example embodiment, the visual system of the present application can satisfy the condition 3.5 < R1 / D1max < 12.5, where R1 is the radius of curvature of the first side of the first lens, and D1max is the maximum outer diameter of the first spacer element. By controlling the ratio of the radius of curvature of the first side of the first lens to the maximum outer diameter of the first spacer element within this range, the axial aberration is corrected and the overall image quality of the system is improved on the basis of limiting the maximum outer shape of the lens barrel.

[0050] In an example embodiment, the visual system of the present application can satisfy the condition 0.7 < |FG2| / (d0m+D0m) < 2.2, where FG2 is the effective focal length of the second element group, d0m is the inner diameter of the second side end surface of the lens barrel, and D0m is the outer diameter of the second side end surface of the lens barrel. By controlling the effective focal length of the second element group and the inner diameter of the second side end surface of the lens barrel and the outer diameter of the second side end surface of the lens barrel to satisfy the condition 0.7 < |FG2| / (d0m+D0m) < 2.2, the shape of the second element group is controlled to determine the reasonable position of the elements, and the wall thickness of the lens barrel can be reasonably controlled, which is beneficial to the molding of the lens barrel.

[0051] In an example embodiment, the visual system of the present application can satisfy the condition 26 < (f / EPD) x (L / EP01) < 41, where f is the effective focal length of the visual system, EPD is the entrance pupil diameter of the visual system, L is the distance from the first side end surface of the lens barrel to the second side end surface of the lens barrel on the optical axis, and EP01 is the distance from the first side end surface of the lens barrel to the first side of the first spacer element along the optical axis. By controlling the effective focal length of the visual system, the entrance pupil diameter of the visual system, the distance from the first side end surface of the lens barrel to the second side end surface of the lens barrel on the optical axis, and the distance from the first side end surface of the lens barrel to the first side of the first spacer element along the optical axis to satisfy the condition 26 < (f / EPD) x (L / EP01) < 41, the field of view of the system can be effectively constrained, so that the system can meet the characteristics of the large field of view of the VR lens.

[0052] In an example embodiment, the visual system of the present application can include at least one diaphragm. The diaphragm can constrain the light path and control the light intensity. The diaphragm can be arranged at a suitable position of the visual system as needed, for example, the diaphragm can be arranged between the first side (human eye side) and the first lens.

[0053] In an example embodiment, the visual system described above can further include a filter for correcting color deviation and / or a protective glass for protecting the photosensitive elements located on the imaging surface.

[0054] According to the visual system of the above-mentioned embodiments of the present application, by arranging the first element group and the second element group sequentially arranged from the first side to the second side along the optical axis in the lens barrel, wherein the first element group has positive focal power, comprising a first lens, a reflective polarizing element, a quarter-wave plate and a second lens; the second element group has negative focal power, comprising a third lens; and a first spacer element is arranged between the first lens and the second lens; at the same time, the effective focal length FG1 of the first element group, the effective focal length FG2 of the second element group, the inner diameter d1m of the second side of the first spacer element and the outer diameter D1m of the second side of the first spacer element satisfy the condition formula 0.5<|FG1+FG2| / (d1m+D1m)<2.5. The arrangement of the visual system disclosed in the present application can limit the shape of the first lens, the second lens and the third lens, meet the support of the first spacer element to the structure of the first lens and the second lens, and be conducive to realizing the compactness of the lens structure and improving the processability.

[0055] The specific embodiments applicable to the visual system of the above-mentioned embodiments will be further described below with reference to the accompanying drawings.

[0056] Example 1

[0057] The visual system according to Embodiment 1 of the present application is described below with reference to Figure 2 , Figure 3 , Figure 4 and Figure 5 , Figure 6 and Figure 7 . Figure 2 , Figure 3 and Figure 4 respectively show the structural schematic diagram of the visual system according to Embodiment 1 of the present application under three different embodiments (Embodiment 1-1, Embodiment 1-2, Embodiment 1-3).

[0058] As shown in Figure 2 , Figure 3 and Figure 4 , the visual system comprises a lens barrel P0 and, arranged in the lens barrel P0 and sequentially arranged from the first side (the side of the human eye) to the second side (the side of the display) along the optical axis: a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2 and a third lens E3; the visual system further comprises an image plane IMG.

[0059] In this embodiment, the first lens E1, the reflective polarizing element RP, the quarter-wave plate QWP and the second lens E2 can constitute a first element group, specifically, the first side (the surface close to the eye side, far from the display side) of the reflective polarizing element RP can be attached to the second side (the surface close to the display side, far from the eye side) of the first lens E1, and the first side (the surface close to the eye side, far from the display side) of the quarter-wave plate QWP can be attached to the second side (the surface close to the display side, far from the eye side) of the reflective polarizing element RP. The first element group has a positive optical power.

[0060] In this embodiment, the second element group includes the third lens E3. The second element group has a negative optical power.

[0061] In this embodiment, the visual system further includes a first spacer element P1 located between the first lens E1 and the second lens E2.

[0062] Table 1 shows the basic parameters of the visual system of embodiment 1, wherein the units of the radius of curvature and the thickness / distance are millimeters (mm).

[0063] Surface Surface type Radius of curvature Thickness Refractive index Abbe number Refractive / reflective Conic constant S0 Sphere Infinity Infinity Refractive S1 Sphere Infinity 15.0000 Refractive S2 Aspheric 795.0596 2.4928 1.54 56.00 Refractive 0.0000 S3 Sphere Infinity 0.2000 1.50 57.00 Refractive S4 Sphere Infinity 0.2000 1.50 57.00 Refractive S5 Sphere Infinity 1.2410 Refractive S6 Aspheric 187.2437 8.7654 1.54 56.00 Refractive 0.0000 S7 Aspheric -94.3088 0.1000 Refractive 0.0000 S8 Aspheric -144.1146 -0.1000 Reflective S9 Aspheric -94.3088 -8.7654 1.54 56.00 Refractive S10 Aspheric 187.2437 -1.2410 Refractive S11 Sphere Infinity -0.2000 1.50 57.00 Refractive S12 Sphere Infinity 0.2000 1.50 57.00 Reflective S13 Sphere Infinity 1.2410 Refractive S14 Aspheric 187.2437 8.7654 1.54 56.00 Refractive S15 Aspheric -94.3088 0.1000 Refractive S16 Aspheric -144.1146 2.0000 1.67 19.00 Refractive 0.0000 S17 Aspheric 128.4419 14.9474 Refractive 0.0000 S18 Sphere Infinity 0.0000 Refractive

[0064] Table 1

[0065] In embodiment 1, the system has a plurality of aspheric surfaces, such as S2, S6-S7 and S16-S17, and each aspheric surface x can be defined by, but not limited to, the following aspheric formula:

[0066]

[0067] wherein x is the sag of the aspheric surface at a height of h along the optical axis, c is the paraxial curvature of the aspheric 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 constant, and Ai is the correction coefficient of the i-th order of the aspheric surface. Table 2 below shows the high-order coefficients A4, A6, A8, A10, A12, A14, A16 and A18 that can be used for the aspheric surfaces S2, S6-S7 and S16-S17 in embodiment 1. 10 12 14 16 18 20 .

[0068] Coefficient\surface S2 S6 S7 S16 S17 A4 -4.3400E-01 3.5666E-01 -3.4261E-01 6.9852E-02 -4.2046E-01 A6 -5.4896E-02 6.7961E-02 -1.6962E-01 7.3732E-02 -1.9244E-01 A8 -2.4334E-02 -1.1773E-01 4.4101E-02 -9.4793E-02 4.3678E-02 A10 -5.0205E-03 -4.9654E-03 -4.8952E-02 3.3669E-02 -7.6622E-03 A12 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A14 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A18 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A20 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00

[0069] Table 2

[0070] The relevant parameter values in this embodiment are shown in Table 7, in combination with Figure 2 , Figure 3 ,​​​​​Figure 4 and Figure 1 wherein d1s is the inner diameter of the first side surface of the first spacer element P1; d1m is the inner diameter of the second side surface of the first spacer element P1; D1s is the outer diameter of the first side surface of the first spacer element P1; D1m is the outer diameter of the second side surface of the first spacer element P1; d0s is the inner diameter of the first side end surface of the lens barrel P0; d0m is the inner diameter of the second side end surface of the lens barrel P0; D0s is the outer diameter of the first side end surface of the lens barrel P0; D0m is the outer diameter of the second side end surface of the lens barrel P0; EP01 is the distance from the first side end surface of the lens barrel P0 to the first side surface of the first spacer element P1 along the optical axis; CP1 is the maximum thickness of the first spacer element P1 along the optical axis; L is the distance from the first side end surface of the lens barrel P0 to the second side end surface of the lens barrel P0 along the optical axis; d0min is the minimum inner diameter of the lens barrel P0; D0max is the maximum outer diameter of the lens barrel P0; d1min is the minimum inner diameter of the first spacer element P1; and D1max is the maximum outer diameter of the first spacer element P1. The units of the above parameters shown in Table 7 are millimeters (mm).

[0071] Figure 5 The on-axis chromatic aberration curve of the visual system of Example 1 is shown, which represents the deviation of the convergent focal points of light rays of different wavelengths after passing through the lens. Figure 6 The astigmatism curve of the visual system of Example 1 is shown, which represents the meridional image surface curvature and sagittal image surface curvature. Figure 7 The distortion curve of the visual system of Example 1 is shown, which represents the distortion size values corresponding to different field angles. Figure 5 to Figure 7 It can be seen that the visual system given in Example 1 can achieve good imaging quality.

[0072] Example 2

[0073] The visual system according to Example 2 of the present application is described below with reference to Figure 8 , Figure 9 , Figure 10 and Figure 11 , Figure 12 and Figure 13 In this embodiment and the following embodiments, for the sake of brevity, some descriptions similar to Example 1 will be omitted. Figure 8 , Figure 9 and Figure 10 respectively show the structural schematic diagrams of the visual system according to Example 2 of the present application under three different implementation manners (Implementation Manner 2-1, Implementation Manner 2-2, Implementation Manner 2-3).

[0074] As Figure 8 , Figure 9 and Figure 10As shown, the visual system includes a lens barrel P0, and sequentially arranged along the optical axis from the first side (the side of the human eye) to the second side (the side of the display) in the lens barrel P0: a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2, and a third lens E3; and the visual system further includes an image plane IMG.

[0075] In this embodiment, the first lens E1, the reflective polarizing element RP, the quarter-wave plate QWP, and the second lens E2 can constitute a first element group, specifically, a first side surface (a surface close to the side of the human eye and away from the side of the display) of the reflective polarizing element RP can be attached to a second side surface (a surface close to the side of the display and away from the side of the human eye) of the first lens E1, and a first side surface (a surface close to the side of the human eye and away from the side of the display) of the quarter-wave plate QWP can be attached to a second side surface (a surface close to the side of the display and away from the side of the human eye) of the reflective polarizing element RP. The first element group has a positive refractive power.

[0076] In this embodiment, the second element group includes the third lens E3. The second element group has a negative refractive power.

[0077] In this embodiment, the visual system further includes a first spacer element P1 located between the first lens E1 and the second lens E2.

[0078] Table 3 shows the basic parameters of the visual system of embodiment 2, wherein the units of the radius of curvature and the thickness / distance are millimeters (mm). In this embodiment, the system has a plurality of aspheric surfaces, such as S2, S6-S7, and S16-S17, and Table 4 shows the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, A30, A32, A34, A36, A38, A40, A42, A44, A46, A48, A50, A52, A54, A56, A58, A60, A62, A64, A66, A68, A70, A72, A74, A76, A78, A80, A82, A84, A86, A88, A90, A92, A94, A96, A98, and A100 of the aspheric surfaces S2, S6-S7, and S16-S17 that can be used in embodiment 2, wherein each aspheric surface can be defined by the formula (1) given in embodiment 1. 10 12 14 16 18 20

[0079] Surface Surface type Radius of curvature Thickness Refractive index Abbe number Refractive / reflective Conic constant S0 Sphere Infinity Infinity Refractive S1 Sphere Infinity 15.0000 Refractive S2 Aspheric 254.6333 2.8942 1.54 56.00 Refractive 0.0000 S3 Sphere Infinity 0.2000 1.50 57.00 Refractive S4 Sphere Infinity 0.2000 1.50 57.00 Refractive S5 Sphere Infinity 1.1970 Refractive S6 Aspheric 276.5146 14.2800 1.54 56.00 Refractive 0.0000 S7 Aspheric -95.1118 0.1000 Refractive 0.0000 S8 Aspheric -138.3532 -0.1000 Reflective S9 Aspheric -95.1118 -14.2800 1.54 56.00 Refractive S10 Aspheric 276.5146 -1.1970 Refractive S11 Sphere Infinity -0.2000 1.50 57.00 Refractive S12 Sphere Infinity 0.2000 1.50 57.00 Reflective S13 Sphere Infinity 1.1970 Refractive S14 Aspheric 276.5146 14.2800 1.54 56.00 Refractive S15 Aspheric -95.1118 0.1000 Refractive S16 Aspheric -138.3532 4.8248 1.67 19.00 Refractive 0.0000 S17 Aspheric 374.0444 6.2593 Refractive 0.0000 S18 Sphere Infinity 0.0000 Refractive

[0080] Table 3

[0081] Coefficient\surface S2 S6 S7 S16 S17 A4 -3.2322E-01 3.4622E-01 -3.1006E-01 8.0621E-02 -2.9268E-01 A6 -1.5510E-02 7.4402E-02 -8.6134E-02 1.0801E-02 -4.0317E-01 A8 -1.4942E-02 -4.2540E-02 1.3720E-01 -6.4907E-02 8.5275E-02 A10 -2.0747E-03 -8.3050E-03 -5.3703E-02 2.0828E-02 -5.0634E-03 A12 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A14 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A18 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A20 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00

[0082] Table 4

[0083] The values of the relevant parameters in embodiment 2 are shown in Table 7, wherein the meanings of the parameters are as described above, which will not be repeated here, and the units of the parameters shown in Table 7 are millimeters (mm).

[0084] Figure 11 ​​​​​​The on-axis chromatic aberration curve of the visual system of Embodiment 2 is shown, which represents the deviation of the convergent focal point of light rays of different wavelengths after passing through the lens. Figure 12 The astigmatism curve of the visual system of Embodiment 2 is shown, which represents the meridional image surface curvature and sagittal image surface curvature. Figure 13 The distortion curve of the visual system of Embodiment 2 is shown, which represents the distortion size values corresponding to different field angles. According to the distortion curve, the distortion size values corresponding to different field angles are shown. Figure 11 to Figure 13 It can be seen that the visual system given in Embodiment 2 can achieve good imaging quality.

[0085] Example 3

[0086] The visual system according to Embodiment 3 of the present application is described below with reference to Figure 14 , Figure 15 , Figure 16 and Figure 17 , Figure 18 and Figure 19 . Figure 14 , Figure 15 and Figure 16 respectively show the structural schematic diagram of the visual system according to Embodiment 3 of the present application under three different embodiments (Embodiment 3-1, Embodiment 3-2, Embodiment 3-3).

[0087] As shown in Figure 14 , Figure 15 and Figure 16 , the visual system comprises a lens barrel P0 and, sequentially arranged along the optical axis from the first side (the side of the human eye) to the second side (the side of the display), a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2 and a third lens E3 which are assembled in the lens barrel P0; the visual system further comprises an image plane IMG.

[0088] In this embodiment, the first lens E1, the reflective polarizing element RP, the quarter-wave plate QWP and the second lens E2 can constitute a first element group, specifically, the first side surface (the surface close to the side of the human eye and away from the side of the display) of the reflective polarizing element RP can be attached to the second side surface (the surface close to the side of the display and away from the side of the human eye) of the first lens E1, and the first side surface (the surface close to the side of the human eye and away from the side of the display) of the quarter-wave plate QWP can be attached to the second side surface (the surface close to the side of the display and away from the side of the human eye) of the reflective polarizing element RP. The first element group has positive refractive power.

[0089] In this embodiment, the second element group comprises the third lens E3. The second element group has negative refractive power.

[0090] In this embodiment, the visual system further comprises a first spacing element P1 located between the first lens E1 and the second lens E2.

[0091] Table 5 shows the basic parameters of the visual system of Example 3, wherein the units of the radius of curvature and the thickness / distance are millimeters (mm). In this example, the system has multiple aspheric surfaces, such as S2, S6-S7, and S16-S17, and the higher order coefficients A4, A6, A8, A10, A12, A14, A16, and A18 of the aspheric surfaces S2, S6-S7, and S16-S17 used in Example 3 are shown in Table 6. 10 12 14 16 18 20 wherein each aspheric surface can be defined by the formula (1) given in Example 1 above.

[0092] Surface Surface type Radius of curvature Thickness Refractive index Abbe number Refractive / reflective Conic constant S0 Sphere Infinity Infinity Refractive S1 Sphere Infinity 15.0000 Refractive S2 Aspheric 251.1249 2.8137 1.54 56.00 Refractive 0.0000 S3 Sphere Infinity 0.2000 1.50 57.00 Refractive S4 Sphere Infinity 0.2000 1.50 57.00 Refractive S5 Sphere Infinity 0.9786 Refractive S6 Aspheric 322.8911 15.7317 1.54 56.00 Refractive 0.0000 S7 Aspheric -94.1298 0.1543 Refractive 0.0000 S8 Aspheric -134.2108 -0.1543 Reflective S9 Aspheric -94.1298 -15.7317 1.54 56.00 Refractive S10 Aspheric 322.8911 -0.9786 Refractive S11 Sphere Infinity -0.2000 1.50 57.00 Refractive S12 Sphere Infinity 0.2000 1.50 57.00 Reflective S13 Sphere Infinity 0.9786 Refractive S14 Aspheric 322.8911 15.7317 1.54 56.00 Refractive S15 Aspheric -94.1298 0.1543 Refractive S16 Aspheric -134.2108 5.3178 1.67 19.00 Refractive 0.0000 S17 Aspheric -6098.8343 4.4574 Refractive 0.0000 S18 Sphere Infinity 0.0000 Refractive

[0093] Table 5

[0094] Coefficient\surface S2 S6 S7 S16 S17 A4 -3.0080E-01 3.6982E-01 -3.0802E-01 8.2294E-02 -1.3435E-01 A6 -1.1303E-02 4.3705E-03 -1.3355E-01 3.8213E-03 -3.7569E-01 A8 -2.1150E-02 2.8420E-03 1.5724E-01 -5.5203E-02 1.1670E-01 A10 1.5462E-04 -1.5506E-02 -4.4261E-02 1.3099E-02 -3.7180E-02 A12 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A14 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A18 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A20 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00

[0095] Table 6

[0096] The values of the relevant parameters in Example 3 are shown in Table 7, wherein the meanings of the parameters are as described above and will not be repeated here, and the units of the parameters shown in Table 7 are millimeters (mm).

[0097] Figure 17 The on-axis chromatic aberration curve of the visual system of Example 3 is shown, which represents the deviation of the converging focal points of light rays of different wavelengths after passing through the lens. Figure 18 The astigmatism curve of the visual system of Example 3 is shown, which represents the meridional image curvature and sagittal image curvature. Figure 19 The distortion curve of the visual system of Example 3 is shown, which represents the distortion values corresponding to different field angles. According to the distortion curve, it can be known that the visual system of Example 3 can achieve good imaging quality. Figure 17 to Figure 19

[0098] Parameter / example 1-1 1-2 1-3 2-1 2-2 2-3 3-1 3-2 3-3 d1s 61.7251 61.2751 61.3751 65.4496 65.7996 66.0996 65.5014 66.0114 65.8114 d1m 63.2021 62.7521 62.8521 66.9067 68.5907 67.5567 66.5687 67.0787 66.8787 D1s 65.2817 64.8317 64.9317 68.9864 69.3364 69.6364 69.0382 69.5482 69.3482 D1m 65.8700 65.4200 65.5200 69.5747 69.9247 70.2247 69.6265 70.1365 69.9365 d0s 46.4674 46.4674 46.4674 50.1720 50.1720 50.1720 50.2239 50.2239 50.2239 d0m 72.3437 71.8937 71.9937 76.0483 76.3983 76.6983 76.1001 76.6101 76.4101 D0s 73.6719 73.1624 73.2445 77.3766 77.7266 78.0266 77.4284 77.9384 77.7384 D0m 77.5613 77.1113 77.2113 81.2660 81.6160 81.9160 81.3178 81.8278 81.6278 EP01 4.8852 5.3852 5.5352 4.3889 4.3889 4.3889 4.2891 4.2891 4.2891 CP1 3.9305 3.9305 3.9305 3.2159 3.2159 3.2159 2.7917 2.7917 2.7917 L 23.7234 24.2234 24.3734 28.3725 28.3725 28.3725 28.3725 28.3725 28.3725 d0min 44.3559 44.3559 44.3559 48.0605 48.0605 48.0605 48.1123 48.1123 48.1123 D0max 79.0000 78.5500 78.6500 82.7046 83.0546 83.3546 82.7565 83.2665 83.0665 d1min 61.2110 60.7610 60.8610 64.9156 65.2656 65.5656 64.9675 65.4775 65.2775 D1max 66.6000 66.1500 66.2500 70.3046 70.6546 70.9546 70.3565 70.8665 70.6665

[0099] Table 7

[0100] In addition, in Examples 1 to 3, the effective focal length FG1 of the first element group, the effective focal length FG2 of the second element group, the effective focal length f of the visual system, the entrance pupil diameter EPD of the visual system, the distance TD of the first side surface of the first lens to the second side surface of the third lens along the optical axis, the center thickness CTR of the reflective polarizing element on the optical axis, and the center thickness CTQ of the quarter-wave plate on the optical axis are shown in Table 8.

[0101] ​​​​​​

[0102]

[0103] Table 8

[0104] Examples 1 to 3 respectively meet the conditions shown in Table 9.

[0105] Condition / example 1-1 1-2 1-3 2-1 2-2 2-3 3-1 3-2 3-3 |FG1+FG2| / (d1m+D1m) 0.72 0.72 0.72 1.37 1.35 1.36 2.12 2.10 2.11 (R3+R4) / (d1s+D1s) 0.73 0.74 0.74 1.35 1.34 1.34 1.70 1.69 1.69 (D0s-d0s) / EPD 5.44 5.34 5.36 5.44 5.51 5.57 5.44 5.54 5.50 f / (EP01+CP1) 3.42 3.24 3.19 4.00 4.00 4.00 4.30 4.30 4.30 d1s / (CT1+CTR+CTQ) 21.34 21.18 21.22 19.87 19.97 20.07 20.38 20.54 20.48 d0m / TD 4.82 4.79 4.80 3.21 3.22 3.24 3.00 3.02 3.01 L / (CT1+CT2+CT3) 1.79 1.83 1.84 1.29 1.29 1.29 1.19 1.19 1.19 |R5| / (D0max-d0min) 4.16 4.21 4.20 3.99 3.95 3.92 3.87 3.82 3.84 d1min / (T12+T23) 35.16 34.90 34.96 38.25 38.46 38.64 42.38 42.72 42.59 R1 / D1max 11.94 12.02 12.00 3.62 3.60 3.59 3.57 3.54 3.55 |FG2| / (d0m+D0m) 0.79 0.80 0.80 1.37 1.37 1.36 2.02 2.01 2.01 (f / EPD)×(L / EP01) 29.31 27.15 26.58 39.36 39.36 39.36 40.31 40.31 40.31

[0106] Table 9

[0107] The present application also provides an imaging device provided with an electronic photosensitive element to image, which can be a Charge Coupled Device (CCD) or a Complementary Metal Oxide Semiconductor (CMOS). The imaging device can be a stand-alone 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 visual system described above.

[0108] The above description is merely preferred embodiments of the present application and a description of the principles of the technology used. Those skilled in the art should understand that the scope of protection of the present application is not limited to the technical solutions formed by the specific combinations of the technical features described above, and should also cover other technical solutions formed by any combinations of the technical features described above or their equivalent features without departing from the concept of the present application. For example, the technical solutions formed by the mutual replacement of the above-described features and the technical features disclosed in the present application (but not limited to) having similar functions.

Claims

1. A visual system, characterized in that, It includes a lens barrel and a first element group and a second element group arranged sequentially from the first side to the second side along the optical axis, assembled within the lens barrel, wherein, The first element group has positive optical power and includes a first lens, a reflective polarizing element, a quarter-wave plate and a second lens arranged sequentially from the first side to the second side along the optical axis; The second element group has negative optical power and includes a third lens; A first spacer element is provided between the first lens and the second lens; The first lens has positive optical power, its first side surface is convex, and its second side surface is planar; The second lens has positive optical power, and its first side surface is convex, and its second side surface is convex. The third lens has negative optical power, and its first side surface is concave. The number of lenses with optical power in the visual system is three; The visual system also includes a semi-transparent and semi-reflective layer disposed on the first side of the third lens; The visual system satisfies: 0.72≤|FG1+FG2| / (d1m+D1m)≤2.12, 0.79≤|FG2| / (d0m+D0m)≤2.02, Wherein, FG1 is the effective focal length of the first element group, FG2 is the effective focal length of the second element group, d1m is the inner diameter of the second side of the first spacer element, D1m is the outer diameter of the second side of the first spacer element, d0m is the inner diameter of the second side end face of the lens barrel, and D0m is the outer diameter of the second side end face of the lens barrel.

2. The visual system according to claim 1, characterized in that, The radius of curvature R3 of the first side surface of the second lens, the radius of curvature R4 of the second side surface of the second lens, the inner diameter d1s of the first side surface of the first spacer element, and the outer diameter D1s of the first side surface of the first spacer element satisfy the following: 0.73≤(R3+R4) / (d1s+D1s)≤1.

70.

3. The visual system according to claim 1, characterized in that, The outer diameter D0s of the first side end face of the lens barrel, the inner diameter d0s of the first side end face of the lens barrel, and the entrance pupil diameter EPD of the visual system satisfy the following: 5.34≤(D0s-d0s) / EPD≤5.

57.

4. The visual system according to claim 1, characterized in that, The effective focal length f of the visual system, the distance EP01 from the first side end face of the lens barrel to the first side face of the first spacer element along the optical axis, and the maximum thickness CP1 of the first spacer element along the optical axis direction satisfy the following: 3.19≤f / (EP01+CP1)≤4.

30.

5. The visual system according to claim 1, characterized in that, The inner diameter d1s of the first side of the first spacer element, the center thickness CT1 of the first lens on the optical axis, the center thickness CTR of the reflective polarizing element on the optical axis, and the center thickness CTQ of the quarter-wave plate on the optical axis satisfy the following: 19.87≤d1s / (CT1+CTR+CTQ)≤21.

34.

6. The visual system according to claim 1, characterized in that, The inner diameter d0m of the second side end face of the lens barrel and the distance TD from the first side face of the first lens to the second side face of the third lens on the optical axis satisfy the following: 3.00≤d0m / TD≤4.

82.

7. The visual system according to any one of claims 1 to 6, characterized in that, The distance L from the first side end face to the second side end face of the lens barrel on the optical axis, the center thickness CT1 of the first lens on the optical axis, the center thickness CT2 of the second lens on the optical axis, and the center thickness CT3 of the third lens on the optical axis satisfy the following: 1.19≤L / (CT1+CT2+CT3)≤1.

84.

8. The visual system according to any one of claims 1 to 6, characterized in that, The radius of curvature R5 of the first side surface of the third lens, the maximum outer diameter D0max of the lens barrel, and the minimum inner diameter d0min of the lens barrel satisfy the following: 3.82≤|R5| / (D0max-d0min)≤4.

21.

9. The visual system according to any one of claims 1 to 6, characterized in that, The minimum inner diameter d1min of the first spacer element, the distance T12 between the second side surface of the first lens and the first side surface of the second lens on the optical axis, and the distance T23 between the second side surface of the second lens and the first side surface of the third lens on the optical axis satisfy the following: 34.90≤d1min / (T12+T23)≤42.

72.

10. The visual system according to any one of claims 1 to 6, characterized in that, The radius of curvature R1 of the first side surface of the first lens satisfies the following condition: 3.5 <R1 / D1max≤12.02。 11. The visual system according to any one of claims 1 to 6, characterized in that, The effective focal length f of the visual system, the entrance pupil diameter EPD of the visual system, the distance L from the first side end face of the lens barrel to the second side end face of the lens barrel on the optical axis, and the distance EP01 from the first side end face of the lens barrel to the first side face of the first spacer element along the optical axis satisfy the following: 26.58≤(f / EPD)×(L / EP01)≤40.

31.

12. A VR device comprising a visual system as described in any one of claims 1 to 11, wherein, The first side is the eye side, and the second side is the display side.

Images