Visual system

Abstract

The invention provides a visual system, which comprises an element group and a lens cone group, when the diopter of the visual system is from + 2D to-5D, the moving distance delta L of the second element group along the optical axis, the combined focal length fz1 of the reflective polarizing element, the first quarter-wave plate and the first lens, and the combined focal length fz2 of the second lens, the second quarter-wave plate and the polarizing film meet the condition that delta L * (fz1 / fz2) is greater than or equal to 0.90 mm and less than or equal to 1.82 mm; and the maximum thickness Lb from the first side surface of the second lens barrel to the second side surface of the second lens barrel along the direction of the optical axis, the outer diameter Dbs of the first side surface of the second lens barrel and the inner diameter dbs of the first side surface of the second lens barrel meet the condition that Lb / (Dbs-dbs) is more than or equal to 0.56 and less than or equal to 2.36. The problem that smooth zooming and image quality improvement of a visual system in the prior art are difficult to consider at the same time is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of head mounted display devices, and in particular to a visual system. Background Art

[0002] With the advancement of science and technology, visual systems have been widely used in many fields. Visual systems are usually required to have high resolution, large field of view, good image quality and compact design. In order to meet these requirements, the design of visual systems has been continuously optimized, among which the improvement of zoom function and optical performance has become a key research direction. During the zoom process, the generation and propagation of stray light is a common problem, which will reduce image clarity and user experience, and aberrations are prone to occur at different focal lengths, resulting in a decrease in image quality. Therefore, it is a very important issue to adjust the size and optical parameters of the lens barrel and optical elements of the visual system to achieve smooth zoom performance while avoiding stray light and aberrations. Summary of the invention

[0003] The main purpose of the present invention is to provide a visual system to solve the problem in the prior art that it is difficult to achieve both smooth zooming and improved image quality in the visual system.

[0004] In order to achieve the above-mentioned object, according to one aspect of the present invention, a visual system is provided, the visual system comprising: an element group, the element group including a first element group and a second element group in sequence from the first side to the second side along the optical axis of the visual system, the second element group being able to move along the direction of the optical axis, the first element group including at least a reflective polarizing element, a first quarter wave plate, a first lens and a partial reflective element along the optical axis from the first side to the second side, the first lens having positive optical power, a first side surface of the first lens being a plane, and a second side surface of the first lens being a convex surface, the second element group including at least a second lens, a second quarter wave plate, a polarizing plate and a display along the optical axis from the first side to the second side, the second lens having positive optical power, a first side surface of the second lens being a convex surface, and a second side surface of the second lens being a plane; and a lens barrel. The lens barrel group includes a first lens barrel and a second lens barrel, the first element group is accommodated in the first lens barrel, and the second element group is accommodated in the second lens barrel; wherein, when the diopter of the visual system changes from +2D to -5D, the distance ΔL moved by the second element group along the optical axis, the combined focal length fz1 of the reflective polarizing element, the first quarter-wave plate and the first lens, and the combined focal length fz2 of the second lens, the second quarter-wave plate and the polarizing plate satisfy the following: 0.90mm≤ΔL×(fz1 / fz2)≤1.82mm; and the maximum thickness Lb from the first side surface of the second lens barrel to the second side surface of the second lens barrel along the optical axis, the outer diameter Dbs of the first side surface of the second lens barrel, and the inner diameter dbs of the first side surface of the second lens barrel satisfy the following: 0.56≤Lb / (Dbs-dbs)≤2.36.

[0005] According to another aspect of the present invention, a visual system is provided, the visual system comprising: an element group, the element group including a first element group and a second element group in sequence from the first side to the second side along the optical axis of the visual system, the second element group being able to move along the direction of the optical axis, the first element group including at least a reflective polarizing element, a first quarter wave plate, a first lens and a partially reflecting element along the optical axis from the first side to the second side, the first lens having positive optical power, a first side surface of the first lens being a plane, and a second side surface of the first lens being a convex surface, the second element group including at least a second lens, a second quarter wave plate, a polarizing plate and a display along the optical axis from the first side to the second side, the second lens having positive optical power, a first side surface of the second lens being a convex surface, and a second side surface of the second lens being a convex surface. The two side surfaces are planes; a lens barrel group, the lens barrel group includes a first lens barrel and a second lens barrel, the first element group is accommodated in the first lens barrel, and the second element group is accommodated in the second lens barrel; wherein, an outer diameter Dam of the second side surface of the first lens barrel, an inner diameter dam of the second side surface of the first lens barrel, and a distance ΔL moved along the optical axis when the refractive power of the visual system ranges from +2D to -5D satisfy: 1.57≤(Dam-dam) / ΔL≤5.60; a maximum thickness Lb from the first side surface of the second lens barrel to the second side surface of the second lens barrel along the direction of the optical axis, an outer diameter Dbs of the first side surface of the second lens barrel, and an inner diameter dbs of the first side surface of the second lens barrel satisfy: 0.56≤Lb / (Dbs-dbs)≤2.36.

[0006] Further, a radius of curvature R2 of the second side surface of the first lens and a maximum thickness La from the first side surface of the first lens barrel to the second side surface of the first lens barrel along the optical axis satisfy: -10.48≤R2 / La≤-6.49.

[0007] Furthermore, a curvature radius R3 of the first side surface of the second lens and an outer diameter Dbm of the second side surface of the second lens barrel satisfy the following relationship: 0.98≤R3 / Dbm≤2.10.

[0008] Further, an outer diameter Das of the first side surface of the first lens barrel, an inner diameter das of the first side surface of the first lens barrel, and a center thickness CT1 of the first lens on the optical axis satisfy: 0.38≤(Das-das) / CT1≤2.26.

[0009] Further, the outer diameter Dbm of the second side surface of the second lens barrel, the center thickness CT2 of the second lens on the optical axis, the center thickness CTQ2 of the second quarter wave plate on the optical axis, and the center thickness CTL of the polarizer on the optical axis satisfy: 3.64≤Dbm / (CT2+CTQ2+CTL)≤5.18.

[0010] Furthermore, the change Δf of the effective focal length of the visual system when the refractive power of the visual system ranges from +2D to -5D, the effective focal length f1 of the first lens, and the maximum thickness La from the first side surface of the first lens barrel to the second side surface of the first lens barrel along the optical axis satisfy the following conditions: 1.73mm≤Δf×(f1 / La)≤4.43mm.

[0011] Further, the effective focal length f2 of the second lens, the inner diameter dbm of the second side surface of the second lens barrel, and the outer diameter Dbm of the second side surface of the second lens barrel satisfy: 0.93≤f2 / (dbm+Dbm)≤2.25.

[0012] Furthermore, an outer diameter Dam of the second side of the first lens barrel, an inner diameter dam of the second side of the first lens barrel, and a distance ΔL that the second element group moves along the optical axis when the refractive power of the visual system ranges from +2D to -5D satisfy the following: 1.57≤(Dam-dam) / ΔL≤5.60.

[0013] Furthermore, the maximum thickness Lb from the first side surface of the second lens barrel to the second side surface of the second lens barrel along the optical axis, the refractive index N2 of the second lens, and the refractive index N1 of the first lens satisfy: 5.23 mm≤Lb×(N2 / N1)≤8.34 mm.

[0014] Furthermore, when the refractive power of the visual system changes from +2D to -5D, the change Δf of the effective focal length of the visual system, the outer diameter Dbs of the first side of the second lens barrel, and the outer diameter Das of the first side of the first lens barrel satisfy the following conditions: 0.15mm≤Δf×(Dbs / Das)≤0.25mm.

[0015] Furthermore, an outer diameter Dam of the second side surface of the first lens barrel and an outer diameter Dbm of the second side surface of the second lens barrel satisfy the following relationship: 0.89≤Dam / Dbm≤1.32.

[0016] Furthermore, the combined focal length fz1 of the reflective polarizing element, the first quarter wave plate and the first lens, the inner diameter das of the first side surface of the first lens barrel and the inner diameter dam of the second side surface of the first lens barrel satisfy: 0.87≤fz1 / (das+dam)≤1.41.

[0017] Further, the combined focal length fz2 of the second lens, the second quarter wave plate and the polarizing plate, and the inner diameter dbm of the second side surface of the second lens barrel satisfy the following relationship: 1.94≤fz2 / dbm≤5.44.

[0018] Furthermore, an outer diameter Dbs of the first side surface of the second lens barrel and an Abbe coefficient V2 of the second lens satisfy the following relationship: 0.6 mm<Dbs / V2<0.85 mm.

[0019] According to the technical solution of the present invention, a visual system includes an element group and a lens barrel group. The element group includes a first element group and a second element group in sequence from a first side to a second side along the optical axis of the visual system. The second element group can move along the direction of the optical axis. The first element group includes at least a reflective polarizing element, a first quarter-wave plate, a first lens and a partial reflective element along the optical axis from the first side to the second side. The first lens has positive focal length, a first side surface of the first lens is a plane, and a second side surface of the first lens is a convex surface. The second element group includes at least a second lens, a second quarter-wave plate, a polarizing plate and a display along the optical axis from the first side to the second side. The second lens has positive focal length, a first side surface of the second lens is a convex surface, and a second side surface of the second lens is a plane. The lens barrel group includes a first lens The lens barrel and the second lens barrel, the first element group is accommodated in the first lens barrel, and the second element group is accommodated in the second lens barrel; wherein, when the refractive power of the visual system changes from +2D to -5D, the distance ΔL moved by the second element group along the optical axis, the combined focal length fz1 of the reflective polarizing element, the first quarter-wave plate and the first lens, and the combined focal length fz2 of the second lens, the second quarter-wave plate and the polarizing plate satisfy the following: 0.90mm≤ΔL×(fz1 / fz2)≤1.82mm; the maximum thickness Lb from the first side surface of the second lens barrel to the second side surface of the second lens barrel along the optical axis, the outer diameter Dbs of the first side surface of the second lens barrel, and the inner diameter dbs of the first side surface of the second lens barrel satisfy the following: 0.56≤Lb / (Dbs-dbs)≤2.36.

[0020] The visual system of the present application is provided with a first element group including at least a reflective polarizing element, a first quarter wave plate, a first lens, and a partially reflective element, and a second element group including a second lens, a second quarter wave plate, a polarizing plate, and a display along the optical axis, and the first element group and the second element group are respectively arranged in the first lens barrel and the second lens barrel, wherein the second lens barrel and the second element group move as a whole along the direction of the optical axis to adjust the diopter of the visual system from +2D to -5D. By controlling the moving distance of the second element group when the diopter changes, the combined focal length of the reflective polarizing element, the first quarter wave plate and the first lens, the combined focal length of the second lens, the second quarter wave plate and the polarizing plate, and the inner and outer diameters of the second lens barrel, and the thickness along the optical axis, it can be ensured that the stray light level of the visual system during the zooming process is kept within an acceptable range, the generation and propagation of stray light is reduced, and the aberration caused by the relative position change of the first element group and the second element group during the zooming process can be further reduced, the user's immersion experience is improved, and the stability of the lens barrel of the visual system is also improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0022] Figure 1 A schematic diagram showing parameters of a visual system in a first state according to an optional embodiment of the present invention is shown;

[0023] Figure 2 Shows Figure 1 Schematic diagram of parameters of the visual system in the second state;

[0024] Figure 3 to Figure 4 A schematic diagram showing the structure of the visual system of the first embodiment of the present invention in the first state and the second state;

[0025] Figures 5 and 6 A schematic diagram showing the structure of the visual system of the second embodiment of the present invention in the first state and the second state;

[0026] Figures 7 and 8 It shows a schematic diagram of the structure of the visual system of the third embodiment of the present invention in the first state and the second state;

[0027] Figures 9 and 10 The MTF curve diagrams of the visual system of the first embodiment of the present invention in the first state and the second state are respectively shown;

[0028] Figure 11 to Figure 12 A schematic diagram showing the structure of a visual system according to a fourth embodiment of the present invention in a first state and a second state;

[0029] Figure 13 to Figure 14 A schematic diagram showing the structure of the visual system of Embodiment 5 of the present invention in a first state and a second state;

[0030] Figure 15 to Figure 16 It shows a schematic diagram of the structure of the visual system of Embodiment 6 of the present invention in a first state and a second state;

[0031] Figure 17 to Figure 18 The MTF curves of the visual system of the fourth embodiment of the present invention in the first state and the second state are shown respectively;

[0032] Figure 19 to Figure 20 It shows a schematic diagram of the structure of the visual system of Embodiment 7 of the present invention in a first state and a second state;

[0033] Figure 21 to Figure 22 A schematic diagram showing the structure of the visual system of Embodiment 8 of the present invention in a first state and a second state;

[0034] Figure 23 to Figure 24 It shows a schematic diagram of the structure of the visual system of Embodiment 9 of the present invention in a first state and a second state;

[0035] Figure 25 to Figure 26The MTF curves of the visual system of the seventh embodiment of the present invention in the first state and the second state are shown respectively;

[0036] Fig. 27 The stray light energy intensity distribution diagram of the visual system of the embodiment 1 of the present invention under the conditions of ΔL×(fz1 / fz2)=1.29mm, Lb / (Dbs-dbs)=2.09 is shown;

[0037] Fig.28 shows the stray light energy intensity distribution diagram of the visual system of Comparative Example 1 under the conditions of ΔL×(fz1 / fz2)=0.6mm, Lb / (Dbs-dbs)=0.4; and

[0038] Fig.29 The stray light energy intensity distribution diagram of the visual system of Comparative Example 2 under the conditions of ΔL×(fz1 / fz2)=2.0mm, Lb / (Dbs-dbs)=2.5 is shown.

[0039] The above drawings include the following reference numerals:

[0040] RP, reflective polarizing element; QWP1, first quarter wave plate; E1, first lens; BS, partial reflection element; E2, second lens; QWP2, second quarter wave plate; LP, polarizing plate; Pa, first lens barrel; Pb, second lens barrel; IMG, image plane. DETAILED DESCRIPTION

[0041] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0042] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0043] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above-mentioned directional words are not used to limit the present invention.

[0044] It should be noted that in this 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, without departing from the teaching of the present application, the first lens discussed below may also be referred to as the second lens or the third lens.

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

[0046] In this article, the paraxial area refers to the area near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial area; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial area. The judgment of the surface shape in the paraxial area can be based on the judgment method of ordinary knowledgeable people in this field, and the positive and negative R value (R refers to the radius of curvature of the paraxial area, usually refers to the R value on the lens database (lens data) in the optical software) is used to judge the convexity and concavity. For the eye-side surface, when the R value is positive, it is judged as a convex surface, and when the R value is negative, it is judged as a concave surface; for the display-side surface, when the R value is positive, it is judged as a concave surface, and when the R value is negative, it is judged as a convex surface.

[0047] In order to solve the problem of smooth zooming and improving image quality of a visual system in the prior art, the present invention provides a visual system.

[0048] First embodiment

[0049] like Figures 1 to 27As shown, the visual system includes an element group and a lens barrel group, the element group includes a first element group and a second element group in sequence from the first side to the second side along the optical axis of the visual system, the second element group can move along the direction of the optical axis, the first element group includes at least a reflective polarizing element, a first quarter wave plate, a first lens and a partial reflective element along the optical axis from the first side to the second side, the first lens has positive focal length, the first side surface of the first lens is a plane, and the second side surface of the first lens is a convex surface, the second element group includes at least a second lens, a second quarter wave plate, a polarizing plate and a display along the optical axis from the first side to the second side, the second lens has positive focal length, the first side surface of the second lens is a convex surface, and the second side surface of the second lens is a plane; the lens barrel group includes a first lens barrel and a second lens barrel. The lens barrel, the first element group is accommodated in the first lens barrel, and the second element group is accommodated in the second lens barrel; wherein, when the diopter of the visual system changes from +2D to -5D, the distance ΔL moved by the second element group along the optical axis, the combined focal length fz1 of the reflective polarizing element, the first quarter-wave plate and the first lens, and the combined focal length fz2 of the second lens, the second quarter-wave plate and the polarizing plate satisfy the following conditions: 0.90mm≤ΔL×(fz1 / fz2)≤1.82mm; and the maximum thickness Lb from the first side surface of the second lens barrel to the second side surface of the second lens barrel along the optical axis, the outer diameter Dbs of the first side surface of the second lens barrel, and the inner diameter dbs of the first side surface of the second lens barrel satisfy the following conditions: 0.56≤Lb / (Dbs-dbs)≤2.36.

[0050] The visual system of the present application is provided with a first element group including at least a reflective polarizing element, a first quarter wave plate, a first lens, and a partially reflective element, and a second element group including a second lens, a second quarter wave plate, a polarizing plate, and a display along the optical axis, and the first element group and the second element group are respectively arranged in the first lens barrel and the second lens barrel, wherein the second lens barrel and the second element group move as a whole along the direction of the optical axis to adjust the diopter of the visual system from +2D to -5D. By controlling the moving distance of the second element group when the diopter changes, the combined focal length of the reflective polarizing element, the first quarter wave plate and the first lens, the combined focal length of the second lens, the second quarter wave plate and the polarizing plate, and the inner and outer diameters of the second lens barrel, and the thickness along the optical axis, it can be ensured that the stray light level of the visual system during the zooming process is kept within an acceptable range, the generation and propagation of stray light is reduced, and the aberration caused by the relative position change of the first element group and the second element group during the zooming process can be further reduced, the user's immersion experience is improved, and the stability of the lens barrel of the visual system is also improved.

[0051] Table 1 below shows the stray light energy intensity distribution of the visual system of Example 1, Comparative Example 1 and Comparative Example 2 when ΔL×(fz1 / fz2) and Lb / (Dbs-dbs) are different. The stray light energy intensity distribution diagram shows the energy distribution peak position corresponding to different values ​​on the imaging surface.

[0052] Table 1

[0053] Embodiment Scheme 1 Comparative Example 1 Comparative Example 2 ΔL×(fz1 / fz2) 1.29mm 0.6mm 2.0mm Lb / (Dbs-dbs) 2.09 0.4 2.5

[0054] When the visual system of Comparative Example 1 satisfies ΔL×(fz1 / fz2)=0.6mm and Lb / (Dbs-dbs)=0.4, the stray light energy intensity distribution is as follows: Fig.28 As shown in FIG. 1 , when the values ​​of ΔL×(fz1 / fz2) and Lb / (Dbs-dbs) are too small, the zoom movement distance of the second element group is small, resulting in inaccurate position changes during zooming and unnecessary scattering and reflection. At the same time, the thickness of the second lens barrel along the optical axis is insufficient, and the slight displacement of the second lens barrel will cause the position of the elements in the second element group to change, increasing the invalid light reflected and scattered inside the visual system, further generating stray light. When the visual system of Comparative Example 2 satisfies ΔL×(fz1 / fz2)=2.0mm、Lb / (Dbs-dbs)=2.5, the stray light energy intensity distribution is as follows: Fig.29 As shown, when the values ​​of ΔL×(fz1 / fz2) and Lb / (Dbs-dbs) are too large, the ratio between the focal length change and the size of the second lens barrel during zooming of the visual system is not coordinated, and more stray light is generated.

[0055] When ΔL×(fz1 / fz2)=1.29mm and Lb / (Dbs-dbs)=2.09 are satisfied in the embodiment 1 of the present application, the stray light energy intensity distribution is as follows: Fig.29 As shown, the visual system has less stray light.

[0056] In this embodiment, the radius of curvature R2 of the second side surface of the first lens and the maximum thickness La from the first side surface of the first lens barrel to the second side surface of the first lens barrel along the optical axis satisfy: -10.48≤R2 / La≤-6.49. By limiting R2 / La within a reasonable range, the relationship between the combined focal length of the first element group and the thickness of the first lens barrel along the optical axis is controlled, and while ensuring the quality of light transmission, the positional relationship between the first lens and the first lens barrel is relatively stable, reducing the generation of stray light and aberrations, thereby ensuring smoothness during zooming and improving the contrast and color accuracy of the image.

[0057] In this embodiment, the radius of curvature R3 of the first side surface of the second lens and the outer diameter Dbm of the second side surface of the second lens barrel satisfy the following conditions: 0.98≤R3 / Dbm≤2.10. By limiting R3 / Dbm within a reasonable range, the relationship between the outer diameter of the second lens and the second side surface of the second lens barrel is controlled, the outer diameter of the second side surface of the second lens barrel is maintained while the refractive power of the second lens is ensured, the light flux received by the second lens from the display is optimized, the light passing through the second lens is ensured to be uniformly transmitted to the first element group, the image is prevented from being partially too bright or too dark, the aberration is reduced, and the image quality of the visual system is improved.

[0058] In this embodiment, the outer diameter Das of the first side surface of the first lens barrel, the inner diameter das of the first side surface of the first lens barrel, and the center thickness CT1 of the first lens on the optical axis satisfy: 0.38≤(Das-das) / CT1≤2.26. By limiting (Das-das) / CT1 within a reasonable range, the wall thickness of the first side surface of the first lens barrel is relatively large, which can match the thickness of the first lens to provide a better processing reference and assembly stability, reduce the difficulty of manufacturing and assembly, help optimize the manufacturing and assembly process of the visual system, and ensure the stable positioning of the first lens in the first lens barrel, reduce the aberration caused by displacement or vibration, so as to maintain the stability and high definition of image quality.

[0059] In this embodiment, the outer diameter Dbm of the second side surface of the second lens barrel, the center thickness CT2 of the second lens on the optical axis, the center thickness CTQ2 of the second quarter wave plate on the optical axis, and the center thickness CTL of the polarizer on the optical axis satisfy the following: 3.64≤Dbm / (CT2+CTQ2+CTL)≤5.18. By limiting Dbm / (CT2+CTQ2+CTL) within a reasonable range and controlling the relationship between the outer diameter of the second side surface of the second lens barrel and the thickness of the second element group on the optical axis, the layout rationality of the second element group can be improved to avoid excessive squeezing or space waste between elements, which can reduce light scattering and reflection inside the second lens barrel, improve the optical path matching between the second element groups, reduce the aberration change in the optical path during zooming, and maintain high definition of image quality.

[0060] In this embodiment, the change Δf of the effective focal length of the visual system when the diopter of the visual system changes from +2D to -5D, the effective focal length f1 of the first lens, and the maximum thickness La from the first side of the first lens barrel to the second side of the first lens barrel along the optical axis satisfy: 1.73mm≤Δf×(f1 / La)≤4.43mm. By limiting Δf×(f1 / La) within a reasonable range, the thickness of the first lens barrel along the optical axis is small, which helps to reduce the overall size and weight of the visual system, improve portability, and make the design of the visual system more compact. At the same time, constraining Δf×(f1 / La) can reduce the generation and change of aberrations during zooming, ensuring that the image quality remains stable and high resolution within the zoom range from +2D to -5D.

[0061] In this embodiment, the effective focal length f2 of the second lens, the inner diameter dbm of the second side surface of the second lens barrel, and the outer diameter Dbm of the second side surface of the second lens barrel satisfy the following relationship: 0.93≤f2 / (dbm+Dbm)≤2.25. By limiting f2 / (dbm+Dbm) within a reasonable range, the internal reflection of the visual system can be reduced, ensuring that the light propagates in a predetermined path, improving the purity of the image, avoiding the excessive light entering the second element group to produce serious stray light ghost images, and avoiding the second lens barrel to shield the effective light. While maintaining high optical performance, the visual system structure can be made more compact by adjusting the focal length of the second lens and the size of the second lens barrel, avoiding excessive increase in the volume of the visual system.

[0062] In this embodiment, the outer diameter Dam of the second side of the first lens barrel, the inner diameter dam of the second side of the first lens barrel, and the distance ΔL that the second element group moves along the optical axis when the diopter of the visual system changes from +2D to -5D satisfy: 1.57≤(Dam-dam) / ΔL≤5.60. By limiting (Dam-dam) / ΔL within a reasonable range, the relationship between the width of the annular band on the second side of the first lens barrel and the maximum moving distance of the second element group during zooming is controlled, which helps to reduce the friction and resistance of the second element group during zooming, improves the response speed and accuracy of zooming, thereby providing a smoother and more responsive zooming experience, and also helps to ensure that the second lens barrel has sufficient structural strength when the second element group moves, avoids deformation of the second lens barrel or element dislocation caused by vibration or displacement, and improves the durability and stability of the visual system.

[0063] In this embodiment, the maximum thickness Lb from the first side surface of the second lens barrel to the second side surface of the second lens barrel along the optical axis, the refractive index N2 of the second lens, and the refractive index N1 of the first lens satisfy the following: 5.23mm≤Lb×(N2 / N1)≤8.34mm. By limiting Lb×(N2 / N1) within a reasonable range, it is possible to ensure that the second lens and the first lens cooperate more harmoniously in the optical path, reduce aberrations, and improve the resolution and contrast of the entire visual system. At the same time, constraining Lb×(N2 / N1) also helps to ensure that the second lens barrel can withstand the weight of internal components and external stress, ensure the precise position of the second element group, avoid deformation of the second lens barrel during zooming or daily use, and avoid the second lens barrel being too thick to reduce user experience, thereby maintaining the high performance of the visual system.

[0064] In this embodiment, when the diopter of the visual system changes from +2D to -5D, the change in the effective focal length of the visual system Δf, the outer diameter Dbs of the first side of the second lens barrel, and the outer diameter Das of the first side of the first lens barrel satisfy the following conditions: 0.15mm≤Δf×(Dbs / Das)≤0.25mm. By limiting Δf×(Dbs / Das) within a reasonable range, it is ensured that the first lens barrel and the second lens barrel have sufficient aperture to support the optical performance, avoid the light incident limit or insufficient intensity due to the small outer diameter of the lens barrel, and avoid the increase in the volume of the visual system due to the large outer diameter of the lens barrel. In addition, the constraint Δf×(Dbs / Das) can also ensure that the visual system can maintain high resolution and good contrast at different diopters, avoid image blur or distortion, and maintain a high-quality visual experience.

[0065] In this embodiment, the outer diameter Dam of the second side surface of the first lens barrel and the outer diameter Dbm of the second side surface of the second lens barrel satisfy the following relationship: 0.89≤Dam / Dbm≤1.32. By limiting Dam / Dbm within a reasonable range, the outer diameter of the second side surface of the first lens barrel is close to the outer diameter of the second side surface of the second lens barrel, simplifying the manufacturing and assembly process of the visual system, reducing the matching tolerance range of the lens barrels, not only helping to reduce production costs, but also improving the reliability and durability of the visual system, and tightly assembling to reduce looseness and wear between components.

[0066] In this embodiment, the combined focal length fz1 of the reflective polarizing element, the first quarter wave plate and the first lens, the inner diameter das of the first side surface of the first lens barrel, and the inner diameter dam of the second side surface of the first lens barrel satisfy: 0.87≤fz1 / (das+dam)≤1.41. By limiting fz1 / (das+dam) within a reasonable range, the propagation path of light inside the first element group can be optimized, aberrations can be reduced, and the clarity and quality of the image at different field angles can be ensured. While maintaining optical performance, the size of the first lens barrel can be more compact, which helps to reduce the overall volume and weight of the visual system and improve portability and user-friendliness.

[0067] In this embodiment, the combined focal length fz2 of the second lens, the second quarter wave plate and the polarizer, and the inner diameter dBm of the second side surface of the second lens barrel satisfy: 1.94≤fz2 / dbm≤5.44. By limiting fz2 / dbm within a reasonable range, the focusing ability of the second element group on light can be optimized, which helps to reduce aberrations and improve the resolution, contrast and color reproduction ability of the visual system. At the same time, constraining fz2 / dbm not only ensures sufficient light flux, but also improves the aberration correction ability.

[0068] In this embodiment, the outer diameter Dbs of the first side surface of the second lens barrel and the dispersion coefficient V2 of the second lens satisfy: 0.6mm<Dbs / V2<0.85mm. By limiting Dbs / V2 within a reasonable range, the dispersion correction capability of the second lens can be controlled, and the focusing points of light of different wavelengths can be better balanced, thereby reducing color separation, thereby optimizing the dispersion correction performance of the visual system, and improving the clarity and color accuracy of the image.

[0069] Second embodiment

[0070] like Figures 1 to 27As shown, the visual system includes an element group and a lens barrel group, the element group includes a first element group and a second element group in sequence from the first side to the second side along the optical axis of the visual system, the second element group can move along the direction of the optical axis, the first element group includes at least a reflective polarizing element, a first quarter wave plate, a first lens and a partial reflective element along the optical axis from the first side to the second side, the first lens has positive optical power, the first side surface of the first lens is a plane, and the second side surface of the first lens is a convex surface, the second element group includes at least a second lens, a second quarter wave plate, a polarizer and a display along the optical axis from the first side to the second side, the second lens has positive optical power, the first side surface of the second lens is a convex surface, and the second side surface of the second lens is a flat surface. The lens barrel group includes a first lens barrel and a second lens barrel, the first element group is accommodated in the first lens barrel, and the second element group is accommodated in the second lens barrel; wherein, an outer diameter Dam of the second side surface of the first lens barrel, an inner diameter dam of the second side surface of the first lens barrel, and a distance ΔL moved along the optical axis when the refractive power of the visual system ranges from +2D to -5D satisfy: 1.57≤(Dam-dam) / ΔL≤5.60; a maximum thickness Lb from the first side surface of the second lens barrel to the second side surface of the second lens barrel in the direction of the optical axis, an outer diameter Dbs of the first side surface of the second lens barrel, and an inner diameter dbs of the first side surface of the second lens barrel satisfy: 0.56≤Lb / (Dbs-dbs)≤2.36.

[0071] The visual system of the present application is provided with a first element group including at least a reflective polarizing element, a first quarter wave plate, a first lens, and a partially reflective element, and a second element group including a second lens, a second quarter wave plate, a polarizing plate, and a display along the optical axis, and the first element group and the second element group are respectively arranged in a first lens barrel and a second lens barrel, wherein the second lens barrel and the second element group move along the direction of the optical axis as a whole to adjust the diopter of the visual system from +2D to -5D. By controlling the inner and outer diameters of the first lens barrel and the second lens barrel and the thickness along the optical axis, and the moving distance of the second element group when the diopter is adjusted, the generation and propagation of stray light can be reduced, and the aberration caused by the relative position change of the first element group and the second element group during the zooming process can be further reduced, and the friction and resistance of the second element group during the zooming can be reduced, and the response speed and accuracy of the zooming can be improved.

[0072] This embodiment may also include other parameter formulas in the first embodiment, which will not be described in detail here.

[0073] In the present application, the mirror surface of at least one of the first lens and the second lens is an aspherical mirror surface. The characteristic of an aspherical lens is that the curvature changes continuously from the center of the lens to the periphery of the lens. Unlike a spherical lens having a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has a better curvature radius characteristic, and has the advantages of improving distortion aberration and improving astigmatism aberration. After adopting an aspherical lens, the aberration occurring during imaging can be eliminated as much as possible, thereby improving the imaging quality.

[0074] However, those skilled in the art should understand that, without departing from the technical solution claimed in the present application, the number of lenses constituting the visual system can be changed to obtain the various results and advantages described in this specification. For example, although two lenses are used as an example in the embodiment, the visual system is not limited to including two lenses. If necessary, the visual system may also include other numbers of lenses.

[0075] Figure 1 and Figure 2 The schematic diagrams of the structure of a visual system of the present application in a first state and a second state are respectively shown. Figure 1 and Figure 2 Parameters such as das are also indicated in the figure to clearly and intuitively understand the meaning of the parameters. In order to facilitate the display of the visual system structure and the specific face shape, these parameters will no longer be reflected in the drawings when describing the specific embodiments later.

[0076] It should be noted that the movement of the second element group of the visual system along the optical axis close to the first element group brings about a change in diopter. The diopter of the visual system is +2D in the first state and -5D in the second state. In the first state, it means that the visual system is suitable for users with a hyperopia of 200 degrees, and in the second state, it means that the visual system is suitable for users with a myopia of 500 degrees. The visual system also has other states besides the first state and the second state, and the diopter of the visual system in other states can be between +2D and -5D.

[0077] It should be noted that the first side refers to the human eye side, the second side refers to the display side, and the image plane is located on the display.

[0078] The following further describes examples of specific surface shapes and parameters of the visual system applicable to the above-mentioned embodiment with reference to the accompanying drawings.

[0079] Embodiment 1

[0080] like Figure 3 to Figure 4 As shown, the structures of the visual system of embodiment 1 of the present application in the first state and the second state are described respectively.

[0081] like Figure 3 to Figure 4As shown, the first element group is accommodated in the first lens barrel Pa, the second element group is accommodated in the second lens barrel Pb, and the visual system includes a reflective polarizing element RP, a first quarter wave plate QWP1, a first lens E1, a partial reflection element BS, a second lens E2, a second quarter wave plate QWP2, and a polarizing plate LP in sequence from the first side to the second side. It should be noted that, in this embodiment, the first side end of the first lens barrel Pa extends in the direction of the optical axis so that the first side surface of the reflective polarizing element RP bears on the first lens barrel Pa, and therefore, the reflective polarizing element RP, the first quarter wave plate QWP1, the first lens E1, and the partial reflection element BS are assembled from the second side of the first lens barrel Pa; at the same time, the second side end of the second lens barrel Pb extends in the direction of the optical axis so that the second side surface of the second lens bears on the second lens barrel Pb, and therefore, the second lens E2, the second quarter wave plate QWP2, and the polarizing plate LP are assembled from the first side of the second lens barrel Pb.

[0082] In this embodiment, the first lens has positive focal power, the first side surface of the first lens is a plane, the second side surface of the first lens is a convex surface, the second lens has positive focal power, the first side surface of the second lens is a convex surface, and the second side surface of the second lens is a plane. The visual system further has an aperture located between the first side and the first element group, the second side surface of the reflective polarizing element is bonded to the first side surface of the first quarter wave plate, the second side surface of the first quarter wave plate is bonded to at least a portion of the first side surface of the first lens, the first side surface of the partial reflective element is bonded to at least a portion of the second side surface of the first lens; the first side surface of the second quarter wave plate is bonded to at least a portion of the second side surface of the second lens, the second side surface of the second quarter wave plate is bonded to the first side surface of the polarizing plate, and the first side surface of the image surface is bonded to at least a portion of the second side surface of the polarizing plate.

[0083] In this embodiment, the light from the image surface IMG passes through the polarizer LP, the second quarter-wave plate QWP2, the second lens E2, the first lens E1, and the first quarter-wave plate QWP1 to reach the reflective polarizing element RP. After being reflected by the reflective polarizing element RP, the light passes through the first quarter-wave plate QWP1 and the first lens E1 in sequence to reach the partially reflecting element BS on the second side surface of the first lens. After being reflected by the partially reflecting element BS, the light is returned to the first lens E1 and the first quarter-wave plate QWP1, and is emitted through the reflective polarizing element RP.

[0084] Table 2 shows the basic structural parameter table of the visual system of Example 1, wherein the units of the curvature radius, thickness / distance, and effective focal length are all in millimeters (mm). In Table 2, the light from the image surface IMG propagates from surface number 14 to the side of surface number 1, and the refraction / reflection is the refraction or reflection effect of the surface on the light during this passage.

[0085] Table 2

[0086]

[0087]

[0088] In the first embodiment, the second side surface of the first lens and the first side surface of the second lens are aspherical surfaces, and the surface shape of the aspherical surface can be defined by but not limited to the following aspherical surface formula:

[0089]

[0090] Wherein, x is the distance vector height from the vertex of the aspheric surface when the aspheric surface is at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface, c=1 / R, that is, the paraxial curvature c is the reciprocal of the curvature radius R in Table 2 above; k is the cone coefficient; Ai is the correction coefficient of the i-th order of the aspheric surface. Table 3 below gives the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for the aspheric surface in Example 1.

[0091] Table 3

[0092] Face number 9 10 A4 3.2268E-06 1.0535E-05 A6 1.4104E-09 -2.6024E-07 A8 1.7916E-11 1.3695E-09 A10 -2.2793E-14 0.0000E+00 A12 -3.9628E-18 0.0000E+00 A14 0.0000E+00 0.0000E+00 A16 0.0000E+00 0.0000E+00 A18 0.0000E+00 0.0000E+00 A20 0.0000E+00 0.0000E+00

[0093] In this embodiment, the second element group is moved to change the diopter of the visual system, so that Figure 3 The first state shown transitions to Figure 4 In the second state shown in Table 4, some structural parameters of the visual system change, wherein D1 represents the value of the virtual image distance of the visual system of this embodiment, and D2 represents the distance from the second side surface of the first lens to the first side surface of the second lens on the optical axis. When D1 and D2 are positive values, it indicates that the direction is from the first side to the second side, and when they are negative values, it indicates that the direction is from the second side to the first side. The units of D1 and D2 are both millimeters (mm).

[0094] Table 4

[0095] Status / Parameters D1 D2 First State 500.0000 2.5181 Second State -200.0000 1.0000

[0096] Fig. 9 and Fig.10 The MTF curves of the visual system of Example 1 in the first state and the second state are shown. The MTF values ​​under the light of each field of view are all above 0.7, showing good imaging quality.

[0097] Embodiment 2

[0098] like Figures 5 and 6 As shown, the visual system of the second embodiment of the present application is described. Figure 5 and Figure 6The first state and the second state of the visual system of Example 2 are described respectively. The visual system of this embodiment has the same optical parameters as that of Example 1, but different structural parameters. Please refer to the relevant description in Example 1, which will not be repeated here.

[0099] Embodiment 3

[0100] like Figures 7 and 8 As shown, the visual system of embodiment 3 of the present application is described. Figure 7 and Figure 8 The first state and the second state of the visual system of Example 3 are described respectively. The visual system of this embodiment has the same optical parameters as that of Example 1, but different structural parameters. Please refer to the relevant description in Example 1, which will not be repeated here.

[0101] Embodiment 4

[0102] like Figure 11 to Figure 12 As shown, the structures of the first state and the second state of the visual system of Example 4 of the present application are respectively described.

[0103] like Figure 11 to Figure 12 As shown, the first element group is accommodated in the first lens barrel Pa, the second element group is accommodated in the second lens barrel Pb, and the visual system includes a reflective polarizing element RP, a first quarter wave plate QWP1, a first lens E1, a partial reflection element BS, a second lens E2, a second quarter wave plate QWP2, and a polarizing plate LP in sequence from the first side to the second side. It should be noted that, in this embodiment, the first side end of the first lens barrel Pa extends in the direction of the optical axis so that the first side surface of the reflective polarizing element RP bears on the first lens barrel Pa, and therefore, the reflective polarizing element RP, the first quarter wave plate QWP1, the first lens E1, and the partial reflection element BS are assembled from the second side of the first lens barrel Pa; at the same time, the second side end of the second lens barrel Pb extends in the direction of the optical axis so that the second side surface of the second lens bears on the second lens barrel Pb, and therefore, the second lens E2, the second quarter wave plate QWP2, and the polarizing plate LP are assembled from the first side of the second lens barrel Pb.

[0104] In this embodiment, the first lens has positive focal power, the first side surface of the first lens is a plane, the second side surface of the first lens is a convex surface, the second lens has positive focal power, the first side surface of the second lens is a convex surface, and the second side surface of the second lens is a plane. The visual system further has an aperture located between the first side and the first element group, the second side surface of the reflective polarizing element is bonded to the first side surface of the first quarter wave plate, the second side surface of the first quarter wave plate is bonded to at least a portion of the first side surface of the first lens, the first side surface of the partial reflective element is bonded to at least a portion of the second side surface of the first lens; the first side surface of the second quarter wave plate is bonded to at least a portion of the second side surface of the second lens, the second side surface of the second quarter wave plate is bonded to the first side surface of the polarizing plate, and the first side surface of the image surface is bonded to at least a portion of the second side surface of the polarizing plate.

[0105] In this embodiment, the light from the image surface IMG passes through the polarizer LP, the second quarter-wave plate QWP2, the second lens E2, the first lens E1, and the first quarter-wave plate QWP1 to reach the reflective polarizing element RP. After being reflected by the reflective polarizing element RP, the light passes through the first quarter-wave plate QWP1 and the first lens E1 in sequence to reach the partially reflecting element BS on the second side surface of the first lens. After being reflected by the partially reflecting element BS, the light returns to the first lens E1 and the first quarter-wave plate QWP1, and is transmitted through the reflective polarizing element RP before being emitted.

[0106] Table 5 shows the basic structural parameter table of the visual system of Example 4, wherein the units of the radius of curvature, thickness / distance, and effective focal length are all in millimeters (mm). In Table 5, the light from the image surface IMG propagates from surface number 14 to the side of surface number 1, and the refraction / reflection is the refraction or reflection effect of the surface on the light during this passage.

[0107] Table 5

[0108] Face number Surface type Radius of curvature thickness Refractive Index Dispersion coefficient Refraction / Reflection Cone coefficient Spherical endless D1 refraction 1 Aperture (STO) Spherical endless 9.0000 refraction 2 Reflective polarizer (RP) Spherical endless 0.1000 1.517 64.17 refraction 3 First Quarter Wave Plate (QWP1) Spherical endless 0.1000 1.517 64.17 refraction 4 First lens (E1) Spherical endless 4.7897 1.639 23.52 refraction 5 Partially reflective element (BS) Aspheric -50.3037 -4.7897 1.639 23.52 reflection 2.9593 6 Spherical endless -0.1000 1.517 64.17 refraction 7 Reflective polarizer (RP) Spherical endless 0.1000 1.517 64.17 reflection 8 First lens (E1) Spherical endless 4.7897 1.639 23.52 refraction 9 Aspheric -50.3037 D2 refraction 2.9593 10 Second lens (E2) Aspheric 39.5956 9.0000 1.544 55.92 refraction 8.3873 11 Second Quarter Wave Plate (QWP2) Spherical endless 0.1000 1.517 64.17 refraction 12 Polarizer(LP) Spherical endless 0.1000 1.517 64.17 refraction 13 Spherical endless 0.0000 refraction 14 Image surface (IMG) Spherical endless 0.0000 refraction

[0109] Table 6 shows the coefficients of higher order terms that can be used for each aspherical mirror surface in the embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above embodiment 1. In this embodiment, the second side surface of the first lens and the first side surface of the second lens are aspherical surfaces.

[0110] Table 6

[0111] Face number 9 10 A4 5.7070E-06 3.3403E-05 A6 -7.2912E-09 -2.6483E-07 A8 1.2163E-10 1.6918E-09 A10 -4.1072E-13 0.0000E+00 A12 5.2266E-16 0.0000E+00 A14 0.0000E+00 0.0000E+00 A16 0.0000E+00 0.0000E+00 A18 0.0000E+00 0.0000E+00 A20 0.0000E+00 0.0000E+00

[0112] In this embodiment, the second element group is moved to change the diopter of the visual system, so that Fig.11 The first state shown transitions to Fig.12In the second state shown in Table 7, some structural parameters of the visual system change, wherein D1 represents the value of the virtual image distance of the visual system of this embodiment, and D2 represents the distance from the second side surface of the first lens to the first side surface of the second lens on the optical axis. When D1 and D2 are positive values, it indicates that the direction is from the first side to the second side, and when they are negative values, it indicates that the direction is from the second side to the first side. The units of D1 and D2 are both millimeters (mm).

[0113] Table 7

[0114] Status / Parameters D1 D2 First State 500.0000 2.1933 Second State -200.0000 1.0000

[0115] Fig.17 and Fig.18 The MTF curves of the visual system of Example 4 in the first state and the second state are shown. The MTF values ​​under the light of each field of view are all above 0.7, showing good imaging quality.

[0116] Embodiment 5

[0117] like Figure 13 to Figure 14 As shown, the visual system of embodiment 5 of the present application is described. Fig.13 and Fig.14 The first state and the second state of the visual system of Example 5 are described respectively. The visual system of this embodiment has the same optical parameters as those of Example 4, but different structural parameters. Please refer to the relevant description of Example 4, which will not be repeated here.

[0118] Embodiment 6

[0119] like Figure 15 to Figure 16 As shown, the visual system of embodiment 6 of the present application is described. Fig.15 and Fig.16 The first state and the second state of the visual system of Example 6 are described respectively. The visual system of this embodiment has the same optical parameters as those of Example 4, but different structural parameters. Please refer to the relevant description in Example 4, which will not be repeated here.

[0120] Embodiment 7

[0121] like Figure 19 to Figure 20 As shown, the structures of the first state and the second state of the visual system of Example 7 of the present application are respectively described.

[0122] like Figure 19 to Figure 20As shown, the first element group is accommodated in the first lens barrel Pa, the second element group is accommodated in the second lens barrel Pb, and the visual system includes a reflective polarizing element RP, a first quarter wave plate QWP1, a first lens E1, a partial reflection element BS, a second lens E2, a second quarter wave plate QWP2, and a polarizing plate LP in sequence from the first side to the second side. It should be noted that, in this embodiment, the first side end of the first lens barrel Pa extends in the direction of the optical axis so that the first side surface of the reflective polarizing element RP bears on the first lens barrel Pa, and therefore, the reflective polarizing element RP, the first quarter wave plate QWP1, the first lens E1, and the partial reflection element BS are assembled from the second side of the first lens barrel Pa; at the same time, the second side end of the second lens barrel Pb extends in the direction of the optical axis so that the second side surface of the second lens bears on the second lens barrel Pb, and therefore, the second lens E2, the second quarter wave plate QWP2, and the polarizing plate LP are assembled from the first side of the second lens barrel Pb.

[0123] In this embodiment, the first lens has positive focal power, the first side surface of the first lens is a plane, the second side surface of the first lens is a convex surface, the second lens has positive focal power, the first side surface of the second lens is a convex surface, and the second side surface of the second lens is a plane. The visual system further has an aperture located between the first side and the first element group, the second side surface of the reflective polarizing element is bonded to the first side surface of the first quarter wave plate, the second side surface of the first quarter wave plate is bonded to at least a portion of the first side surface of the first lens, the first side surface of the partial reflective element is bonded to at least a portion of the second side surface of the first lens; the first side surface of the second quarter wave plate is bonded to at least a portion of the second side surface of the second lens, the second side surface of the second quarter wave plate is bonded to the first side surface of the polarizing plate, and the first side surface of the image surface is bonded to at least a portion of the second side surface of the polarizing plate.

[0124] In this embodiment, the light from the image surface IMG passes through the polarizer LP, the second quarter-wave plate QWP2, the second lens E2, the first lens E1, and the first quarter-wave plate QWP1 to reach the reflective polarizing element RP. After being reflected by the reflective polarizing element RP, the light passes through the first quarter-wave plate QWP1 and the first lens E1 in sequence to reach the partially reflecting element BS on the second side surface of the first lens. After being reflected by the partially reflecting element BS, the light returns to the first lens E1 and the first quarter-wave plate QWP1, and is transmitted through the reflective polarizing element RP before being emitted.

[0125] Table 8 shows the basic structural parameter table of the visual system of Example 7, wherein the units of the radius of curvature, thickness / distance, and effective focal length are all in millimeters (mm). In Table 8, the light from the image surface IMG propagates from surface number 14 to the side of surface number 1, and the refraction / reflection is the refraction or reflection effect of the surface on the light during this passage.

[0126] Table 8

[0127] surface Surface type Radius of curvature thickness Refractive Index Dispersion coefficient Refraction / Reflection Cone coefficient 0 Spherical endless D1 refraction 1 Aperture (STO) Spherical endless 13.0000 refraction 2 Reflective polarizer (RP) Spherical endless 0.1000 1.517 64.17 refraction 3 First Quarter Wave Plate (QWP1) Spherical endless 0.1000 1.517 64.17 refraction 4 First lens (E1) Spherical endless 7.9973 1.810 41.00 refraction 5 Partially reflective element (BS) Aspheric -66.6356 -7.9973 1.810 41.00 reflection 3.5114 6 Spherical endless -0.1000 1.517 64.17 refraction 7 Reflective polarizer (RP) Spherical endless 0.1000 1.517 64.17 reflection 8 First lens (E1) Spherical endless 7.9973 1.810 41.00 refraction 9 Aspheric -66.6356 D2 refraction 3.5114 10 Second lens (E2) Aspheric 86.3340 9.0000 1.544 55.92 refraction 25.3678 11 Second Quarter Wave Plate (QWP2) Spherical endless 0.1000 1.517 64.17 refraction 12 Polarizer(LP) Spherical endless 0.1000 1.517 64.17 refraction 13 Spherical endless 0.0000 refraction 14 Image surface (IMG) Spherical endless 0.0000 refraction

[0128] Table 9 shows the high-order coefficients that can be used for each aspherical mirror surface in the embodiment, wherein the surface shape of each aspherical surface can be defined by the formula (1) given in the above embodiment 1. In this embodiment, the second side surface of the first lens and the first side surface of the second lens are aspherical surfaces.

[0129] Table 9

[0130] Face number 9 10 A4 2.8237E-06 2.8805E-05 A6 -4.0411E-09 -2.3764E-07 A8 2.4381E-11 7.0914E-10 A10 -3.7137E-14 0.0000E+00 A12 2.1215E-17 0.0000E+00 A14 0.0000E+00 0.0000E+00 A16 0.0000E+00 0.0000E+00 A18 0.0000E+00 0.0000E+00 A20 0.0000E+00 0.0000E+00

[0131] In this embodiment, the second element group is moved to change the diopter of the visual system, so that Fig.19 The first state shown transitions to Fig. 20 In the second state shown in Table 10, some structural parameters of the visual system change, wherein D1 represents the value of the virtual image distance of the visual system of this embodiment, and D2 represents the distance from the second side surface of the first lens to the first side surface of the second lens on the optical axis. When D1 and D2 are positive values, it indicates that the direction is from the first side to the second side, and when they are negative values, it indicates that the direction is from the second side to the first side. The units of D1 and D2 are both millimeters (mm).

[0132] Status / Parameters D1 D2 First State 500.0000 2.7364 Second State -200.0000 1.0000

[0133] Fig.25 and Fig.26 The MTF curves of the visual system of Example 7 in the first state and the second state are shown. The MTF values ​​under the light of each field of view are all above 0.7, showing good imaging quality.

[0134] Embodiment 8

[0135] like Figure 21 to Figure 22 As shown, the visual system of embodiment eight of the present application is described. Figure 21 to Figure 22 The first state and the second state of the visual system of Example 8 are described respectively. The visual system of this embodiment has the same optical parameters as that of Example 7, but different structural parameters. Please refer to the relevant description in Example 7, which will not be repeated here.

[0136] Embodiment 9

[0137] like Figure 23 to Figure 24 As shown, the visual system of embodiment 9 of the present application is described. Fig.23 and Fig.24 The first state and the second state of the visual system of Example 9 are described respectively. The visual system of this embodiment has the same optical parameters as that of Example 7, but different structural parameters. Please refer to the relevant description in Example 7, which will not be repeated here.

[0138] In summary, the first to ninth embodiments of the visual system respectively satisfy the relationship shown in Table 11. The conditional expressions of the first state and the second state corresponding to each embodiment of the visual system have the same values.

[0139] Table 11

[0140] Conditional / Example 1 2 3 4 5 6 7 8 9 ΔL×(fz1 / fz2)(mm) 1.82 1.82 1.82 1.29 1.29 1.29 0.90 0.90 0.90 Lb / (Dbs-dbs) 1.70 1.68 0.91 2.09 2.09 0.56 2.20 2.36 0.59 R2 / La -8.11 -10.48 -9.66 -8.07 -6.49 -7.49 -8.66 -8.25 -8.38 R3 / Dbm 1.18 1.14 1.01 1.18 1.17 0.98 2.08 2.10 1.81 (Das-das) / CT1 2.06 0.50 2.05 2.17 0.84 2.26 2.04 0.38 1.43 Dbm / (CT2+CTQ2+CTL) 4.06 4.20 4.71 3.64 3.69 4.38 4.51 4.47 5.18 Δf×(f1 / La)(mm) 3.43 4.43 4.08 2.40 1.93 2.23 1.82 1.73 1.76 f2 / (dbm+Dbm) 1.25 1.37 0.97 1.37 1.38 0.93 2.25 2.24 1.71 (Dam-dam) / ΔL 1.80 5.60 1.80 2.30 4.55 2.30 1.57 3.11 1.57 Lb×(N2 / N1)(mm) 6.41 6.31 5.28 7.86 8.34 5.45 7.51 8.05 5.23 Δf×(Dbs / Das)(mm) 0.25 0.24 0.24 0.22 0.19 0.21 0.16 0.15 0.17 Dam / Dbm 1.32 1.19 1.09 1.08 0.99 0.89 1.29 1.22 1.04 fz1 / (das+dam) 1.28 1.18 1.31 1.41 1.26 1.40 0.98 0.87 1.02 fz2 / dbm 2.97 3.99 2.01 3.75 3.88 1.94 5.44 5.34 3.53 Dbs / V2(mm) 0.68 0.71 0.63 0.68 0.69 0.66 0.82 0.82 0.79

[0141] Table 12 gives the effective focal lengths and some structural parameters of each lens and element group of the visual system of Examples 1 to 9, in mm.

[0142] Table 12

[0143]

[0144]

[0145] Table 13 gives some structural parameters of the visual systems of Examples 1 to 9, in units of mm.

[0146] Table 13

[0147] Parameters / Examples 1 2 3 4 5 6 7 8 9 das 26.540 40.868 26.596 22.296 34.358 22.843 33.194 49.714 33.244 dam 41.063 32.474 39.463 33.585 28.101 33.276 50.603 44.790 47.074 Das 40.185 44.205 40.175 32.707 38.358 33.661 49.525 52.714 44.684 Dam 43.796 40.985 42.195 36.317 33.513 36.008 53.335 50.202 49.806 dbs 33.790 35.428 29.285 34.040 34.242 26.506 41.976 41.615 33.678 dbm 24.288 18.060 35.909 19.437 18.762 37.581 29.154 29.698 44.967 Dbs 37.790 39.428 35.417 38.040 38.473 36.917 45.976 45.615 44.089 Dbm 33.263 34.408 38.641 33.513 33.963 40.314 41.449 41.087 47.699 La 6.809 5.269 5.717 6.237 7.752 6.718 7.696 8.077 7.949 Lb 6.805 6.702 5.601 8.347 8.857 5.784 8.807 9.440 6.130

[0148] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0149] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0150] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned 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 numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0151] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A visual system, characterized in that: The visual system comprises: An element group, the element group includes a first element group and a second element group in sequence from a first side to a second side along the optical axis of the visual system, the second element group is capable of moving along the direction of the optical axis, the first element group includes at least a reflective polarizing element, a first quarter wave plate, a first lens and a partial reflective element along the optical axis from the first side to the second side, the first lens has positive optical power, a first side surface of the first lens is a plane, and a second side surface of the first lens is a convex surface, the second element group includes at least a second lens, a second quarter wave plate, a polarizing plate and a display along the optical axis from the first side to the second side, the second lens has positive optical power, a first side surface of the second lens is a convex surface, and a second side surface of the second lens is a plane; A lens barrel group, the lens barrel group comprising a first lens barrel and a second lens barrel, the first element group is accommodated in the first lens barrel, and the second element group is accommodated in the second lens barrel; Wherein, when the diopter of the visual system changes from +2D to -5D, the distance ΔL moved by the second element group along the optical axis, the combined focal length fz1 of the reflective polarizing element, the first quarter wave plate and the first lens, and the combined focal length fz2 of the second lens, the second quarter wave plate and the polarizing plate satisfy the following conditions: 0.90 mm≤ ΔL×(fz1 / fz2)≤1.82mm; The maximum thickness Lb from the first side surface of the second lens barrel to the second side surface of the second lens barrel along the optical axis, the outer diameter Dbs of the first side surface of the second lens barrel, and the inner diameter dbs of the first side surface of the second lens barrel satisfy: 0.56≤Lb / (Dbs-dbs)≤2.

36.

2. The visual system according to claim 1, characterized in that: A curvature radius R2 of the second side surface of the first lens and a maximum thickness La from the first side surface of the first lens barrel to the second side surface of the first lens barrel along the optical axis satisfy the following: -10.48≤R2 / La≤-6.

49.

3. The visual system according to claim 1, characterized in that: A curvature radius R3 of the first side surface of the second lens and an outer diameter Dbm of the second side surface of the second lens barrel satisfy the following: 0.98≤R3 / Dbm≤2.

10.

4. The visual system according to claim 1, characterized in that: An outer diameter Das of the first side surface of the first lens barrel, an inner diameter das of the first side surface of the first lens barrel, and a center thickness CT1 of the first lens on the optical axis satisfy the following: 0.38≤(Das-das) / CT1≤2.

26.

5. The visual system according to claim 1, characterized in that: The outer diameter Dbm of the second side surface of the second lens barrel, the center thickness CT2 of the second lens on the optical axis, the center thickness CTQ2 of the second quarter wave plate on the optical axis, and the center thickness CTL of the polarizer on the optical axis satisfy: 3.64≤Dbm / (CT2+CTQ2+CTL)≤5.

18.

6. The visual system according to claim 1, characterized in that: When the refractive power of the visual system ranges from +2D to -5D, the change Δf in the effective focal length of the visual system, the effective focal length f1 of the first lens, and the maximum thickness La from the first side surface of the first lens barrel to the second side surface of the first lens barrel along the optical axis satisfy the following conditions: 1.73mm≤Δf×(f1 / La)≤4.43mm.

7. The visual system according to claim 1, characterized in that: The effective focal length f2 of the second lens, the inner diameter dbm of the second side surface of the second lens barrel, and the outer diameter Dbm of the second side surface of the second lens barrel satisfy the following: 0.93≤f2 / (dbm+Dbm)≤2.

25.

8. The visual system according to claim 1, characterized in that: The outer diameter Dam of the second side of the first lens barrel, the inner diameter dam of the second side of the first lens barrel, and the distance ΔL that the second element group moves along the optical axis when the refractive power of the visual system ranges from +2D to -5D satisfy the following: 1.57≤(Dam-dam) / ΔL≤5.

60.

9. The visual system according to claim 1, characterized in that: The maximum thickness Lb from the first side surface of the second lens barrel to the second side surface of the second lens barrel along the optical axis, the refractive index N2 of the second lens, and the refractive index N1 of the first lens satisfy the following: 5.23 mm ≤ Lb × (N2 / N1) ≤ 8.34 mm.

10. The visual system according to claim 1, characterized in that: When the refractive power of the visual system changes from +2D to -5D, the change Δf of the effective focal length of the visual system, the outer diameter Dbs of the first side of the second lens barrel, and the outer diameter Das of the first side of the first lens barrel satisfy the following relationship: 0.15mm≤Δf×(Dbs / Das)≤0.25mm.

11. The visual system according to claim 1, characterized in that: An outer diameter Dam of the second side surface of the first lens barrel and an outer diameter Dbm of the second side surface of the second lens barrel satisfy the following: 0.89≤Dam / Dbm≤1.

32.

12. The visual system according to claim 1, characterized in that: The combined focal length fz1 of the reflective polarizing element, the first quarter-wave plate and the first lens, the inner diameter das of the first side surface of the first lens barrel and the inner diameter dam of the second side surface of the first lens barrel satisfy: 0.87≤fz1 / (das+dam)≤1.

41.

13. The visual system according to claim 1, characterized in that: The combined focal length fz2 of the second lens, the second quarter wave plate and the polarizing plate, and the inner diameter dbm of the second side surface of the second lens barrel satisfy the following: 1.94≤fz2 / dbm≤5.

44.

14. The visual system according to claim 1, characterized in that: An outer diameter Dbs of the first side surface of the second lens barrel and an Abbe coefficient V2 of the second lens satisfy the following relationship: 0.6 mm<Dbs / V2<0.85 mm.

Images