Visual system

Abstract

The utility model 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] This utility model relates to the field of head-mounted display technology, and more specifically, to a visual system. Background Technology

[0002] With the advancement of technology, visual systems have been widely applied in numerous fields. Visual systems typically require high resolution, a wide field of view, good image quality, and a compact design. To meet these requirements, the design of visual systems is constantly being optimized, with improvements in zoom functionality and optical performance becoming key research directions. During zooming, the generation and propagation of stray light is a common problem, reducing image sharpness and user experience, and easily introducing aberrations at different focal lengths, leading to a decline in image quality. Therefore, adjusting 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 is a crucial issue. Utility Model Content

[0003] The main objective of this invention is to provide a visual system that solves the problem in the prior art of simultaneously achieving smooth zooming and improved image quality in visual systems.

[0004] To achieve the above objectives, according to one aspect of the present invention, a visual system is provided, comprising: an element group, the element group including a first element group and a second element group sequentially from a first side to a second side along the optical axis of the visual system, the second element group being movable 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 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 planar, and a second side surface of the first lens being convex; the second element group including 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 having positive optical power, a first side surface of the second lens being convex, and a second side surface of the second lens being planar; and a mirror. The lens assembly includes a first lens barrel and a second lens barrel. A first element group is housed within the first lens barrel, and a second element group is housed within the second lens barrel. The following parameters satisfy the following: 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; 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 polarizer: 0.90mm ≤ ΔL × (fz1 / fz2) ≤ 1.82mm. The maximum thickness Lb from the first side surface 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: 0.56 ≤ Lb / (Dbs-dbs) ≤ 2.36.

[0005] According to another aspect of the present invention, a visual system is provided, comprising: an element group, the element group including a first element group and a second element group sequentially from a first side to a second side along the optical axis of the visual system, the second element group being movable 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 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 planar, and a second side surface of the first lens being convex; the second element group including 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 having positive optical power, a first side surface of the second lens being convex, and the second lens... The second side is a plane; the lens assembly includes a first lens tube and a second lens tube, a first element group is housed in the first lens tube, and a second element group is housed in the second lens tube; wherein, the outer diameter Dam of the second side of the first lens tube, the inner diameter dam of the second side of the first lens tube, and the distance ΔL that the second element group moves along the optical axis when the refractive power of the visual system changes from +2D to -5D satisfy the following: 1.57≤(Dam-dam) / ΔL≤5.60; the maximum thickness Lb from the first side of the second lens tube to the second side of the second lens tube along the optical axis, the outer diameter Dbs of the first side of the second lens tube, and the inner diameter dbs of the first side of the second lens tube satisfy the following: 0.56≤Lb / (Dbs-dbs)≤2.36.

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

[0007] Furthermore, the radius of curvature R3 of the first side of the second lens and the outer diameter Dbm of the second side of the second lens tube satisfy the following condition: 0.98≤R3 / Dbm≤2.10.

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

[0009] Furthermore, the outer diameter Dbm of the second side 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.

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

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

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

[0013] Furthermore, the maximum thickness Lb from the first side to the second side 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.

[0014] Furthermore, when the refractive power 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 tube, and the outer diameter Das of the first side of the first lens tube satisfy the following condition: 0.15mm≤Δf×(Dbs / Das)≤0.25mm.

[0015] Furthermore, the outer diameter Dam of the second side of the first lens tube and the outer diameter Dbm of the second side of the second lens tube satisfy the following condition: 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 of the first lens barrel and the inner diameter dam of the second side of the first lens barrel satisfy the following condition: 0.87≤fz1 / (das+dam)≤1.41.

[0017] Furthermore, 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 of the second lens barrel satisfy the following condition: 1.94≤fz2 / dbm≤5.44.

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

[0019] Applying the technical solution of this utility model, the visual system includes an element group and a lens barrel group. The element group, along the optical axis of the visual system from the first side to the second side, sequentially includes a first element group and a second element group. The second element group is movable along the direction of the optical axis. The first element group, along the optical axis from the first side to the second side, includes at least a reflective polarizing element, a first quarter-wave plate, a first lens, and a partially reflective element. The first lens has positive optical power, its first side surface is planar, and its second side surface is convex. The second element group, along the optical axis from the first side to the second side, includes at least a second lens, a second quarter-wave plate, a polarizer, and a display. The second lens has positive optical power, its first side surface is convex, and its second side surface is planar. The lens barrel group includes a first... The first and second lens tubes are respectively housed within the first lens tube and the second lens tube. The distance ΔL that the second lens tube moves along the optical axis when the refractive power of the visual system changes from +2D to -5D, 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 polarizer satisfy the following: 0.90mm ≤ ΔL × (fz1 / fz2) ≤ 1.82mm. The maximum thickness Lb from the first side to the second side of the second lens tube along the optical axis, the outer diameter Dbs of the first side of the second lens tube, and the inner diameter dbs of the first side of the second lens tube satisfy the following: 0.56 ≤ Lb / (Dbs-dbs) ≤ 2.36.

[0020] The visual system of this application comprises a first element group along the optical axis, 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 polarizer, and a display. The first and second element groups are respectively disposed within a first lens barrel and a second lens barrel. The second lens barrel and the second element group move as a whole along the optical axis to adjust the refractive power of the visual system from +2D to -5D. By controlling the moving distance of the second element group, 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 polarizer, as well as the inner and outer diameters and the thickness along the optical axis of the second lens barrel during refractive power changes, it is possible to ensure that the stray light level of the visual system remains within an acceptable range during zooming, reducing the generation and propagation of stray light. Furthermore, it can reduce aberrations caused by changes in the relative positions of the first and second element groups during zooming, improving the user's immersive experience and enhancing the stability of the visual system's lens barrel. Attached Figure Description

[0021] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:

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

[0023] Figure 2 It shows Figure 1 A schematic diagram of the parameters of the visual system in the second state;

[0024] Figures 3 to 4 The diagram shows a structural schematic of the visual system of Embodiment 1 of the present invention in a first state and a second state;

[0025] Figures 5 to 6 The diagram shows a schematic representation of the visual system of Embodiment 2 of this invention in a first state and a second state.

[0026] Figures 7 to 8 The diagram shows a schematic representation of the visual system of Embodiment 3 of this utility model in a first state and a second state.

[0027] Figures 9 to 10 The MTF curves of the visual system of Embodiment 1 of this utility model in the first state and the second state are shown respectively.

[0028] Figures 11 to 12 The diagram shows a schematic diagram of the visual system of Embodiment 4 of this utility model in the first and second states.

[0029] Figures 13 to 14 The diagram shows a structural schematic of the visual system of Embodiment 5 of this utility model in a first state and a second state;

[0030] Figures 15 to 16 The diagram shows a schematic representation of the visual system of Embodiment Six of this invention in a first state and a second state.

[0031] Figures 17 to 18 The MTF curves of the visual system of Embodiment 4 of this utility model in the first state and the second state are shown respectively;

[0032] Figures 19 to 20 The diagram shows a structural schematic of the visual system of Embodiment 7 of this utility model in a first state and a second state;

[0033] Figures 21 to 22 The diagram shows a structural schematic of the visual system of Embodiment 8 of this utility model in a first state and a second state;

[0034] Figures 23 to 24 The diagram shows a structural schematic of the visual system of Embodiment 9 of this utility model in a first state and a second state;

[0035] Figures 25 to 26 The MTF curves of the visual system of Embodiment 7 of this utility model in the first state and the second state are shown respectively;

[0036] Figure 27 The diagram shows the stray light energy intensity distribution of the visual system under the conditions of ΔL×(fz1 / fz2)=1.29mm and Lb / (Dbs-dbs)=2.09 according to embodiment 1 of this utility model.

[0037] Figure 28 The stray light energy intensity distribution of the visual system in Comparative Example 1 is shown under the conditions of ΔL×(fz1 / fz2)=0.6mm and Lb / (Dbs-dbs)=0.4; and

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

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

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

[0041] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0042] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0043] In this utility model, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" are generally used in relation to the direction shown in the accompanying drawings, or in relation to the vertical, perpendicular, or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not used to limit this utility model.

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

[0045] In the accompanying drawings, 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 illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not drawn strictly to scale.

[0046] In this paper, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of that convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of that concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The determination of the surface shape in the paraxial region can be based on the judgment method commonly used by those knowledgeable in the field, using the R value (R refers to the radius of curvature of the paraxial region, usually the R value in the lens database of optical software) to determine convexity or concavity. For the eye-side surface, when the R value is positive, it is determined to be convex, and when the R value is negative, it is determined to be concave; for the display-side surface, when the R value is positive, it is determined to be concave, and when the R value is negative, it is determined to be convex.

[0047] To address the issues of smooth zooming and improved image quality in existing visual systems, this invention provides a visual system.

[0048] First Implementation Method

[0049] like Figures 1 to 27As shown, the visual system includes an element group and a lens barrel group. The element group, along the optical axis of the visual system from the first side to the second side, sequentially includes a first element group and a second element group. The second element group is movable along the optical axis. The first element group, along the optical axis from the first side to the second side, includes at least a reflective polarizing element, a first quarter-wave plate, a first lens, and a partially reflective element. The first lens has positive optical power, a first side surface of the first lens is planar, and a second side surface of the first lens is convex. The second element group, along the optical axis from the first side to the second side, includes at least a second lens, a second quarter-wave plate, a polarizer, and a display. The second lens has positive optical power, a first side surface of the second lens is convex, and a second side surface of the second lens is planar. The lens barrel group includes a first lens barrel and a second... The lens barrel has a first element group housed within it and a second element group housed within it. The distance ΔL from which the second element group moves along the optical axis when the refractive power of the visual system changes from +2D to -5D, 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 polarizer satisfy the following: 0.90mm ≤ ΔL × (fz1 / fz2) ≤ 1.82mm. The maximum thickness Lb from the first side to the second side of the second lens barrel along the optical axis, the outer diameter Dbs of the first side of the second lens barrel, and the inner diameter dbs of the first side of the second lens barrel satisfy the following: 0.56 ≤ Lb / (Dbs-dbs) ≤ 2.36.

[0050] The visual system of this application comprises a first element group along the optical axis, 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 polarizer, and a display. The first and second element groups are respectively disposed within a first lens barrel and a second lens barrel. The second lens barrel and the second element group move as a whole along the optical axis to adjust the refractive power of the visual system from +2D to -5D. By controlling the moving distance of the second element group, 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 polarizer, as well as the inner and outer diameters and the thickness along the optical axis of the second lens barrel during refractive power changes, it is possible to ensure that the stray light level of the visual system remains within an acceptable range during zooming, reducing the generation and propagation of stray light. Furthermore, it can reduce aberrations caused by changes in the relative positions of the first and second element groups during zooming, improving the user's immersive experience and enhancing the stability of the visual system's lens barrel.

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

[0052] Table 1

[0053] Example 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: Figure 28 As shown, when 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. Simultaneously, the thickness of the second lens barrel along the optical axis is insufficient, and even small displacements of the second lens barrel can cause changes in the position of the elements in the second element group, increasing the amount of ineffective light reflected and scattered within the visual system, further generating stray light. In Comparative Example 2, when the visual system satisfies ΔL×(fz1 / fz2)=2.0mm and Lb / (Dbs-dbs)=2.5, the stray light energy intensity distribution is as follows: Figure 29 As shown, when ΔL×(fz1 / fz2) and Lb / (Dbs-dbs) are too large, the ratio between the focal length change and the second lens barrel size during zooming is not coordinated, resulting in more stray light.

[0055] In embodiment 1 of this application, when ΔL×(fz1 / fz2)=1.29mm and Lb / (Dbs-dbs)=2.09, the stray light energy intensity distribution is as follows: Figure 29 As shown, the visual system produces 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 of the first lens barrel from the first side surface to the second side surface along the optical axis satisfy the following condition: -10.48 ≤ R2 / La ≤ -6.49. By limiting R2 / La to 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. This ensures the relative stability of the positional relationship between the first lens and the first lens barrel while guaranteeing the quality of light transmission, reducing stray light and aberrations, thereby ensuring smoothness during zooming and improving image contrast and color accuracy.

[0057] In this embodiment, the radius of curvature R3 of the first side of the second lens and the outer diameter Dbm of the second side of the second lens barrel satisfy the following relationship: 0.98 ≤ R3 / Dbm ≤ 2.10. By limiting R3 / Dbm within a reasonable range, the relationship between the second lens and the outer diameter of the second side of the second lens barrel is controlled. This ensures the refractive power of the second lens while maintaining the outer diameter of the second side of the second lens barrel, optimizes the light flux received by the second lens from the display, ensures that the light passing through the second lens is uniformly transmitted to the first element group, avoids local overbrightness or underbrightness in the image, reduces aberrations, and improves the image quality of the visual system.

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

[0059] In this embodiment, the outer diameter Dbm of the second side 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 condition: 3.64 ≤ Dbm / (CT2+CTQ2+CTL) ≤ 5.18. By limiting Dbm / (CT2+CTQ2+CTL) to a reasonable range, the relationship between the outer diameter of the second side of the second lens barrel and the thickness of the second element group on the optical axis can be controlled. This improves the rationality of the layout of the second element group, avoiding excessive compression or wasted space between elements. It can reduce light scattering and reflection inside the second lens barrel, improve the optical path matching degree between the second element groups, reduce aberration changes in the optical path during zooming, and maintain high image clarity.

[0060] In this embodiment, the effective focal length change Δf of the visual system from +2D to -5D, the effective focal length f1 of the first lens, and the maximum thickness La along the optical axis from the first side to the second side of the first lens barrel satisfy the following: 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 smaller, 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 changes 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 of the second lens barrel, and the outer diameter Dbm of the second side of the second lens barrel satisfy the following condition: 0.93 ≤ f2 / (dbm+Dbm) ≤ 2.25. By limiting f2 / (dbm+Dbm) within a reasonable range, internal reflections of the visual system can be reduced, ensuring that light propagates along a predetermined path, improving image purity, preventing excessive light from entering the second element group and causing severe stray ghosting, and also preventing the second lens barrel from blocking effective light. While maintaining high optical performance, adjusting the focal length of the second lens and the size of the second lens barrel allows for a more compact visual system structure, avoiding excessive increase in the size 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 refractive power of the visual system changes from +2D to -5D satisfy the following condition: 1.57 ≤ (Dam - dam) / ΔL ≤ 5.60. By limiting (Dam - dam) / ΔL to a reasonable range, the relationship between the width of the annular band on the second side of the first lens barrel and the maximum zoom movement distance of the second element group is controlled. This helps to reduce the friction and resistance of the second element group during zooming, improve the zoom response speed and accuracy, thereby providing a smoother and faster zooming experience. It also helps to ensure that the second lens barrel has sufficient structural strength when the second element group moves, avoiding deformation of the second lens barrel or misalignment of the elements due to vibration or displacement, and improving the durability and stability of the visual system.

[0063] In this embodiment, the maximum thickness Lb of the second lens barrel from its first side to its second side along the optical axis, the refractive index N2 of the second lens, and the refractive index N1 of the first lens satisfy the following condition: 5.23mm ≤ Lb×(N2 / N1) ≤ 8.34mm. By limiting Lb×(N2 / N1) to a reasonable range, the coordination between the second lens and the first lens in the optical path can be ensured to be more harmonious, reducing aberrations and improving the resolution and contrast of the entire visual system. Simultaneously, constraining Lb×(N2 / N1) also helps ensure that the second lens barrel can withstand the weight of internal components and external stress, ensuring the precise position of the second component assembly, preventing deformation of the second lens barrel during zooming or daily use, and avoiding excessive thickness of the second lens barrel that would reduce user experience, thus maintaining the high performance of the visual system.

[0064] In this embodiment, the effective focal length change Δf of the visual system when the refractive power of the visual system changes from +2D to -5D, 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 condition: 0.15mm ≤ Δf × (Dbs / Das) ≤ 0.25mm. By limiting Δf × (Dbs / Das) within a reasonable range, it is ensured that the first and second lens barrels have sufficient aperture to support optical performance, avoiding limited light incidence or insufficient intensity due to excessively small lens barrel outer diameters, and also avoiding an increase in the size of the visual system due to excessively large lens barrel outer diameters. In addition, constraining Δf × (Dbs / Das) can also ensure that the visual system can maintain high resolution and good contrast under different refractive powers, avoiding image blurring or distortion, and maintaining a high-quality visual experience.

[0065] In this embodiment, the outer diameter Dam of the second side of the first lens barrel and the outer diameter Dbm of the second side of the second lens barrel satisfy the following condition: 0.89 ≤ Dam / Dbm ≤ 1.32. By limiting Dam / Dbm within a reasonable range, the outer diameters of the second side of the first lens barrel and the second side of the second lens barrel are close, simplifying the manufacturing and assembly process of the visual system and reducing the fit tolerance range of the lens barrels. This not only helps to reduce production costs but also improves the reliability and durability of the visual system, and the tight assembly reduces 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 of the first lens barrel, and the inner diameter dam of the second side of the first lens barrel satisfy the following condition: 0.87 ≤ fz1 / (das+dam) ≤ 1.41. By limiting fz1 / (das+dam) within a reasonable range, the propagation path of light within the first element group can be optimized, aberrations can be reduced, and image sharpness and quality can be ensured at different field of view angles. While maintaining optical performance, the size of the first lens barrel can be more compact, helping to reduce the overall size and weight of the visual system, improving 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 of the second lens barrel satisfy the following condition: 1.94 ≤ fz2 / dBm ≤ 5.44. By limiting fz2 / dBm within a reasonable range, the focusing capability of the second element group can be optimized, which helps to reduce aberrations and improve the resolution, contrast, and color reproduction capability of the visual system. Simultaneously, constraining fz2 / dBm improves aberration correction capability while ensuring sufficient light throughput.

[0068] In this embodiment, the outer diameter Dbs of the first side of the second lens barrel and the dispersion coefficient V2 of the second lens satisfy the following condition: 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, the focusing points of different wavelengths of light can be better balanced, thereby reducing color separation, optimizing the dispersion correction performance of the visual system, and improving image clarity and color accuracy.

[0069] Second Implementation Method

[0070] like Figures 1 to 27As shown, the visual system includes an element group and a lens group. The element group, along the optical axis of the visual system from the first side to the second side, sequentially includes a first element group and a second element group. The second element group is movable along the optical axis. The first element group, along the optical axis from the first side to the second side, includes at least a reflective polarizing element, a first quarter-wave plate, a first lens, and a partially reflective element. The first lens has positive optical power, its first side surface is flat, and its second side surface is convex. The second element group, along the optical axis from the first side to the second side, includes at least a second lens, a second quarter-wave plate, a polarizer, and a display. The second lens has positive optical power, its first side surface is convex, and its second side surface is flat. The lens assembly includes a first lens tube and a second lens tube, with a first element group housed within the first lens tube and a second element group housed within the second lens tube. The outer diameter Dam of the second side of the first lens tube, the inner diameter dam of the second side of the first lens tube, and the distance ΔL that the second element group moves along the optical axis when the refractive power of the visual system changes from +2D to -5D satisfy the following: 1.57 ≤ (Dam - dam) / ΔL ≤ 5.60. The maximum thickness Lb from the first side of the second lens tube to the second side of the second lens tube along the optical axis, the outer diameter Dbs of the first side of the second lens tube, and the inner diameter dbs of the first side of the second lens tube satisfy the following: 0.56 ≤ Lb / (Dbs - dbs) ≤ 2.36.

[0071] The visual system of this application comprises a first element group along the optical axis, 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 polarizer, and a display. The first and second element groups are respectively disposed within a first lens barrel and a second lens barrel. The second lens barrel and the second element group move as a whole along the optical axis to adjust the refractive power of the visual system from +2D to -5D. By controlling the inner and outer diameters and thicknesses along the optical axis of the first and second lens barrels, as well as the moving distance of the second element group during refractive power adjustment, the generation and propagation of stray light can be reduced, and aberrations caused by the relative positional changes of the first and second element groups during zooming can be further reduced. Furthermore, it helps to reduce friction and resistance of the second element group during zooming, thereby improving the zoom response speed and accuracy.

[0072] This embodiment may also include other parametric expressions from the first embodiment, which will not be elaborated here.

[0073] In this application, at least one of the first and second lenses has an aspherical mirror surface. An aspherical lens is characterized by a continuously changing curvature from its center to its periphery. Unlike a spherical lens, which has a constant curvature from its center to its periphery, an aspherical lens has superior curvature radius characteristics, offering advantages in improving distortion and astigmatism. By using an aspherical lens, aberrations occurring during imaging can be eliminated as much as possible, thereby improving image quality.

[0074] However, those skilled in the art will understand that the number of lenses constituting the visual system can be varied to obtain the various results and advantages described herein without departing from the technical solutions claimed in this application. For example, although two lenses are described as an example in the embodiments, 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 diagrams show the structure of a visual system of this application in the first and second states, respectively. Figure 1 and Figure 2 The accompanying drawings also indicate parameters such as das to clearly and intuitively explain their meaning. To facilitate the demonstration of the visual system structure and specific surface shapes, these parameters will not be shown in the subsequent descriptions of specific embodiments.

[0076] It should be noted that the movement of the second element group of the visual system closer to the first element group along the optical axis causes a change in refractive power. The refractive power of the visual system is +2D in the first state and -5D in the second state. Specifically, the first state indicates that the visual system is suitable for users with a hyperopia of 200 diopters, and the second state indicates that the visual system is suitable for users with a myopia of 500 diopters. The visual system also has other states besides the first and second states, and the refractive power of the visual system in these other states can be between +2D and -5D.

[0077] It should be noted that the first side refers to the side of the human eye, and the second side refers to the side of the display screen, with the image surface located on the display screen.

[0078] The following describes in further detail, with reference to the accompanying drawings, specific surface features and parameters of the visual system applicable to the above embodiments.

[0079] Example 1

[0080] like Figures 3 to 4 As shown, the structure of the visual system of Embodiment 1 of this application in the first state and the second state are described respectively.

[0081] like Figures 3 to 4As shown, the first element group is housed within the first lens barrel Pa, and the second element group is housed within the second lens barrel Pb. The visual system, from the first side to the second side, sequentially includes a reflective polarizing element RP, a first quarter-wave plate QWP1, a first lens E1, a partially reflective element BS, a second lens E2, a second quarter-wave plate QWP2, and a polarizer LP. It should be noted that in this embodiment, the first end of the first lens barrel Pa extends towards the optical axis so that the first side of the reflective polarizing element RP rests against the first lens barrel Pa. Therefore, the reflective polarizing element RP, the first quarter-wave plate QWP1, the first lens E1, and the partially reflective element BS are assembled from the second side of the first lens barrel Pa. Simultaneously, the second end of the second lens barrel Pb extends towards the optical axis so that the second side of the second lens rests against the second lens barrel Pb. Therefore, the second lens E2, the second quarter-wave plate QWP2, and the polarizer LP are assembled from the first side of the second lens barrel Pb.

[0082] In this embodiment, the first lens has positive optical power, a first side surface of the first lens is planar, and a second side surface of the first lens is convex. The second lens also has positive optical power, a first side surface of the second lens is convex, and a second side surface of the second lens is planar. The visual system further includes an aperture stop located between the first side and the first element group. The second side surface of the reflective polarizing element is in contact with the first side surface of the first quarter-wave plate. The second side surface of the first quarter-wave plate is in contact with at least a portion of the first side surface of the first lens. The first side surface of the partially reflective element is in contact with at least a portion of the second side surface of the first lens. The first side surface of the second quarter-wave plate is in contact with at least a portion of the second side surface of the second lens. The second side surface of the second quarter-wave plate is in contact with the first side surface of the polarizer. The first side surface of the image plane is in contact with at least a portion of the second side surface of the polarizer.

[0083] In this embodiment, light from the image plane IMG passes through polarizer LP, second quarter-wave plate QWP2, second lens E2, first lens E1, and first quarter-wave plate QWP1 before reaching reflective polarizer RP. After being reflected by reflective polarizer RP, the light passes through first quarter-wave plate QWP1 and first lens E1 in sequence before reaching partial reflective element BS on the second side of the first lens. After being reflected by partial reflective element BS, the light returns to first lens E1 and first quarter-wave plate QWP1, and exits through reflective polarizer RP.

[0084] Table 2 shows the basic structural parameters of the visual system in Embodiment 1. The units of radius of curvature, thickness / distance, and effective focal length are all millimeters (mm). In Table 2, light from the image surface IMG propagates from surface number 14 to the side of surface number 1. Refraction / reflection refers to the refraction or reflection of light by that surface during this passage.

[0085] Table 2

[0086]

[0087]

[0088] In Embodiment 1, the second side surface of the first lens and the first side surface of the second lens are aspherical surfaces. The shape of the aspherical surface can be defined using, but is not limited to, the following aspherical surface formula:

[0089]

[0090] Where x is the distance vector from the vertex of the aspherical surface at a height h along the optical axis; c is the paraxial curvature of the aspherical surface, c = 1 / R, that is, the paraxial curvature c is the reciprocal of the radius of curvature R in Table 2 above; k is the conic coefficient; Ai is the i-th order correction coefficient of the aspherical surface. Table 3 below gives the higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for the aspherical 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, moving the second element group changes the refractive power of the visual system, thereby achieving the desired effect. Figure 3 The first state transition shown is to Figure 4 The second state shown in Table 4 is characterized by changes in some structural parameters of the visual system. In this state, D1 represents the virtual image distance of the visual system in this embodiment, and D2 represents the distance on the optical axis between the second side of the first lens and the first side of the second lens. When D1 and D2 are positive, the direction is from the first side to the second side, and when they are negative, 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] Figure 9 and Figure 10 The MTF curves of the visual system of Embodiment 1 are shown in the first state and the second state, respectively. The MTF values ​​under the light of each field of view are all above 0.7, showing good imaging quality.

[0097] Example 2

[0098] like Figures 5 to 6 The image shows a visual system according to Embodiment 2 of this application. Figure 5 and Figure 6The first and second states of the visual system in Embodiment 2 are described respectively. The visual system in this embodiment has the same optical parameters as that in Embodiment 1, but different structural parameters. Please refer to the relevant description in Embodiment 1, which will not be repeated here.

[0099] Example 3

[0100] like Figures 7 to 8 The image shows a visual system according to Embodiment 3 of this application. Figure 7 and Figure 8 The first and second states of the visual system in Embodiment 3 are described respectively. The visual system in this embodiment has the same optical parameters as that in Embodiment 1, but different structural parameters. Please refer to the relevant description in Embodiment 1, which will not be repeated here.

[0101] Example 4

[0102] like Figures 11 to 12 As shown, the structures of the first and second states of the visual system of Embodiment 4 of this application are described respectively.

[0103] like Figures 11 to 12 As shown, the first element group is housed within the first lens barrel Pa, and the second element group is housed within the second lens barrel Pb. The visual system, from the first side to the second side, sequentially includes a reflective polarizing element RP, a first quarter-wave plate QWP1, a first lens E1, a partially reflective element BS, a second lens E2, a second quarter-wave plate QWP2, and a polarizer LP. It should be noted that in this embodiment, the first end of the first lens barrel Pa extends towards the optical axis so that the first side of the reflective polarizing element RP rests against the first lens barrel Pa. Therefore, the reflective polarizing element RP, the first quarter-wave plate QWP1, the first lens E1, and the partially reflective element BS are assembled from the second side of the first lens barrel Pa. Simultaneously, the second end of the second lens barrel Pb extends towards the optical axis so that the second side of the second lens rests against the second lens barrel Pb. Therefore, the second lens E2, the second quarter-wave plate QWP2, and the polarizer LP are assembled from the first side of the second lens barrel Pb.

[0104] In this embodiment, the first lens has positive optical power, a first side surface of the first lens is planar, and a second side surface of the first lens is convex. The second lens also has positive optical power, a first side surface of the second lens is convex, and a second side surface of the second lens is planar. The visual system further includes an aperture stop located between the first side and the first element group. The second side surface of the reflective polarizing element is in contact with the first side surface of the first quarter-wave plate. The second side surface of the first quarter-wave plate is in contact with at least a portion of the first side surface of the first lens. The first side surface of the partially reflective element is in contact with at least a portion of the second side surface of the first lens. The first side surface of the second quarter-wave plate is in contact with at least a portion of the second side surface of the second lens. The second side surface of the second quarter-wave plate is in contact with the first side surface of the polarizer. The first side surface of the image plane is in contact with at least a portion of the second side surface of the polarizer.

[0105] In this embodiment, light from the image plane IMG passes through polarizer LP, second quarter-wave plate QWP2, second lens E2, first lens E1, and first quarter-wave plate QWP1 before reaching reflective polarizer RP. After being reflected by reflective polarizer RP, the light passes sequentially through first quarter-wave plate QWP1 and first lens E1 before reaching partial reflective element BS on the second side of the first lens. After being reflected by partial reflective element BS, the light returns to first lens E1 and first quarter-wave plate QWP1, and is then transmitted through reflective polarizer RP before exiting.

[0106] Table 5 shows the basic structural parameters of the visual system in Embodiment 4. The units for radius of curvature, thickness / distance, and effective focal length are all millimeters (mm). In Table 5, light from the image surface IMG propagates from surface number 14 to the side of surface number 1. Refraction / reflection refers to the refraction or reflection of light by that surface during this passage.

[0107] Table 5

[0108] Face number Surface type radius of curvature thickness Refractive index Dispersion coefficient Refraction / Reflection Conic coefficient spherical endless D1 refraction 1 Stabilizer (STO) spherical endless 9.0000 refraction 2 Reflective polarizing element (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 Partial reflective element (BS) aspherical -50.3037 -4.7897 1.639 23.52 reflection 2.9593 6 spherical endless -0.1000 1.517 64.17 refraction 7 Reflective polarizing element (RP) spherical endless 0.1000 1.517 64.17 reflection 8 First lens (E1) spherical endless 4.7897 1.639 23.52 refraction 9 aspherical -50.3037 D2 refraction 2.9593 10 Second lens (E2) aspherical 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 Polarizing filter (LP) spherical endless 0.1000 1.517 64.17 refraction 13 spherical endless 0.0000 refraction 14 Image View (IMG) spherical endless 0.0000 refraction

[0109] Table 6 shows the higher-order coefficients that can be used for each aspherical mirror in the embodiments, wherein the surface shape of each aspherical surface can be defined by formula (1) given in Embodiment 1 above. 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, moving the second element group changes the refractive power of the visual system, thereby achieving the desired effect. Figure 11 The first state transition shown is to Figure 12The second state shown in Table 7 is characterized by changes in some structural parameters of the visual system. In this state, D1 represents the virtual image distance of the visual system in this embodiment, and D2 represents the distance on the optical axis between the second side of the first lens and the first side of the second lens. When D1 and D2 are positive, the direction is from the first side to the second side, and when they are negative, 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] Figure 17 and Figure 18 The MTF curves of the visual system of Embodiment 4 are shown in the first and second states, respectively. The MTF values ​​under the light of each field of view are all above 0.7, showing good imaging quality.

[0116] Example 5

[0117] like Figures 13 to 14 The image shows a visual system according to Embodiment 5 of this application. Figure 13 and Figure 14 The first and second states of the visual system in Embodiment 5 are described respectively. The visual system in this embodiment has the same optical parameters as that in Embodiment 4, but different structural parameters. Please refer to the relevant description in Embodiment 4, which will not be repeated here.

[0118] Example 6

[0119] like Figures 15 to 16 The image shows a visual system according to Embodiment Six of this application. Figure 15 and Figure 16 The first and second states of the visual system in Embodiment Six are described respectively. The visual system in this embodiment has the same optical parameters as that in Embodiment Four, but different structural parameters. Please refer to the relevant description in Embodiment Four, which will not be repeated here.

[0120] Example 7

[0121] like Figures 19 to 20 As shown, the structures of the first and second states of the visual system of Embodiment Seven of this application are described respectively.

[0122] like Figures 19 to 20As shown, the first element group is housed within the first lens barrel Pa, and the second element group is housed within the second lens barrel Pb. The visual system, from the first side to the second side, sequentially includes a reflective polarizing element RP, a first quarter-wave plate QWP1, a first lens E1, a partially reflective element BS, a second lens E2, a second quarter-wave plate QWP2, and a polarizer LP. It should be noted that in this embodiment, the first end of the first lens barrel Pa extends towards the optical axis so that the first side of the reflective polarizing element RP rests against the first lens barrel Pa. Therefore, the reflective polarizing element RP, the first quarter-wave plate QWP1, the first lens E1, and the partially reflective element BS are assembled from the second side of the first lens barrel Pa. Simultaneously, the second end of the second lens barrel Pb extends towards the optical axis so that the second side of the second lens rests against the second lens barrel Pb. Therefore, the second lens E2, the second quarter-wave plate QWP2, and the polarizer LP are assembled from the first side of the second lens barrel Pb.

[0123] In this embodiment, the first lens has positive optical power, a first side surface of the first lens is planar, and a second side surface of the first lens is convex. The second lens also has positive optical power, a first side surface of the second lens is convex, and a second side surface of the second lens is planar. The visual system further includes an aperture stop located between the first side and the first element group. The second side surface of the reflective polarizing element is in contact with the first side surface of the first quarter-wave plate. The second side surface of the first quarter-wave plate is in contact with at least a portion of the first side surface of the first lens. The first side surface of the partially reflective element is in contact with at least a portion of the second side surface of the first lens. The first side surface of the second quarter-wave plate is in contact with at least a portion of the second side surface of the second lens. The second side surface of the second quarter-wave plate is in contact with the first side surface of the polarizer. The first side surface of the image plane is in contact with at least a portion of the second side surface of the polarizer.

[0124] In this embodiment, light from the image plane IMG passes through polarizer LP, second quarter-wave plate QWP2, second lens E2, first lens E1, and first quarter-wave plate QWP1 before reaching reflective polarizer RP. After being reflected by reflective polarizer RP, the light passes sequentially through first quarter-wave plate QWP1 and first lens E1 before reaching partial reflective element BS on the second side of the first lens. After being reflected by partial reflective element BS, the light returns to first lens E1 and first quarter-wave plate QWP1, and is then transmitted through reflective polarizer RP before exiting.

[0125] Table 8 shows the basic structural parameters of the visual system of Embodiment 7, in which the units of radius of curvature, thickness / distance, and effective focal length are all 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 refraction / reflection refers to the refraction or reflection of light by that surface during this passage.

[0126] Table 8

[0127] surface Surface type radius of curvature thickness Refractive index Dispersion coefficient Refraction / Reflection Conic coefficient 0 spherical endless D1 refraction 1 Stabilizer (STO) spherical endless 13.0000 refraction 2 Reflective polarizing element (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 Partial reflective element (BS) aspherical -66.6356 -7.9973 1.810 41.00 reflection 3.5114 6 spherical endless -0.1000 1.517 64.17 refraction 7 Reflective polarizing element (RP) spherical endless 0.1000 1.517 64.17 reflection 8 First lens (E1) spherical endless 7.9973 1.810 41.00 refraction 9 aspherical -66.6356 D2 refraction 3.5114 10 Second lens (E2) aspherical 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 Polarizing filter (LP) spherical endless 0.1000 1.517 64.17 refraction 13 spherical endless 0.0000 refraction 14 Image View (IMG) spherical endless 0.0000 refraction

[0128] Table 9 shows the higher-order coefficients that can be used for each aspherical mirror in the embodiments, wherein the surface shape of each aspherical surface can be defined by formula (1) given in Embodiment 1 above. 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]

[0131]

[0132] In this embodiment, moving the second element group changes the refractive power of the visual system, thereby achieving the desired effect. Figure 19 The first state transition shown is to Figure 20 The second state shown in Table 10 is characterized by changes in some structural parameters of the visual system. In this embodiment, D1 represents the virtual image distance of the visual system, and D2 represents the distance on the optical axis between the second side of the first lens and the first side of the second lens. When D1 and D2 are positive, the direction is from the first side to the second side, and when they are negative, the direction is from the second side to the first side. The units of D1 and D2 are both millimeters (mm).

[0133] Table 10

[0134] Status / Parameters D1 D2 First state 500.0000 2.7364 Second state -200.0000 1.0000

[0135] Figure 25 and Figure 26 The MTF curves of the visual system of Embodiment 7 are shown in the first state and the second state, respectively. The MTF values ​​under the light of each field of view are all above 0.7, showing good imaging quality.

[0136] Example 8

[0137] like Figures 21 to 22 The image shows a visual system according to Embodiment 8 of this application. Figures 21 to 22 The first and second states of the visual system in Embodiment 8 are described respectively. The visual system in this embodiment has the same optical parameters as that in Embodiment 7, but different structural parameters. Please refer to the relevant description in Embodiment 7, which will not be repeated here.

[0138] Example 9

[0139] like Figures 23 to 24 The image shows a visual system according to Embodiment Nine of this application. Figure 23 and Figure 24The first and second states of the visual system in Embodiment 9 are described respectively. The visual system in this embodiment has the same optical parameters as that in Embodiment 7, but different structural parameters. Please refer to the relevant description in Embodiment 7, which will not be repeated here.

[0140] In summary, embodiments one through nine of the visual system satisfy the relationships shown in Table 11. Specifically, the conditional values ​​for the first and second states corresponding to each embodiment of the visual system are identical.

[0141] Table 11

[0142]

[0143]

[0144] Table 12 shows the effective focal length and some structural parameters of each lens and component group of the visual system in Examples 1 to 9, in mm.

[0145] Table 12

[0146] Parameters / Examples 1 2 3 4 5 6 7 8 9 f1 86.41 86.41 86.41 78.70 78.70 78.70 82.27 82.27 82.27 f2 72.10 72.10 72.10 72.80 72.80 72.80 158.73 158.73 158.73 fz1 86.41 86.41 86.41 78.70 78.70 78.70 82.27 82.27 82.27 fz2 72.10 72.10 72.10 72.80 72.80 72.80 158.73 158.73 158.73 ΔL 1.52 1.52 1.52 1.19 1.19 1.19 1.74 1.74 1.74 Δf 0.27 0.27 0.27 0.19 0.19 0.19 0.17 0.17 0.17

[0147] Table 13 shows some structural parameters of the visual systems of Examples 1 to 9, in mm.

[0148] Table 13

[0149] 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

[0150] Obviously, the embodiments described above are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0151] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0152] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0153] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A visual system, characterized in that, The visual system includes: The component group includes, sequentially from a first side to a second side along the optical axis of the visual system, a first component group and a second component group. The second component group is movable along the direction of the optical axis. The first component group, from the first side to the second side along the optical axis, includes at least a reflective polarizing element, a first quarter-wave plate, a first lens, and a partially reflective element. The first lens has positive optical power, a first side surface of the first lens is planar, and a second side surface of the first lens is convex. The second component group, from the first side to the second side along the optical axis, includes at least a second lens, a second quarter-wave plate, a polarizer, and a display. The second lens has positive optical power, a first side surface of the second lens is convex, and a second side surface of the second lens is planar. The lens barrel assembly includes a first lens barrel and a second lens barrel, wherein the first element group is housed in the first lens barrel and the second element group is housed in the second lens barrel; Wherein, when the refractive power of the visual system ranges from +2D to -5D, the distance ΔL that the second element group moves 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 polarizer satisfy the following condition: 0.90mm ≤ ΔL×(fz1 / fz2)≤1.82mm; The maximum thickness Lb from the first side to the second side of the second lens barrel along the optical axis, the outer diameter Dbs of the first side of the second lens barrel, and the inner diameter dbs of the first side of the second lens barrel satisfy the following condition: 0.56≤Lb / (Dbs-dbs)≤2.

36.

2. The visual system according to claim 1, characterized in that, The radius of curvature R2 of the second side of the first lens and the maximum thickness La of the first side 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, The radius of curvature R3 of the first side of the second lens and the outer diameter Dbm of the second side of the second lens barrel satisfy the following condition: 0.98≤R3 / Dbm≤2.

10.

4. The visual system according to claim 1, characterized in that, The outer diameter Das of the first side of the first lens barrel, the inner diameter das of the first side of the first lens barrel, and the center thickness CT1 of the first lens on the optical axis satisfy the following condition: 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 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.

6. 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 in the effective focal length Δf of the visual system, the effective focal length f1 of the first lens, and the maximum thickness La of the first side surface to the second side surface of the first lens barrel along the optical axis satisfy the following: 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 of the second lens barrel, and the outer diameter Dbm of the second side of the second lens barrel satisfy the following condition: 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 tube, the inner diameter dam of the second side of the first lens tube, and the distance ΔL that the second element group moves along the optical axis when the refractive power of the visual system changes 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 to the second side 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.

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 in the effective focal length Δf 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 condition: 0.15mm≤Δf×(Dbs / Das)≤0.25mm.

11. The visual system according to claim 1, characterized in that, The outer diameter Dam of the second side of the first lens tube and the outer diameter Dbm of the second side of the second lens tube satisfy the following condition: 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 of the first lens barrel, and the inner diameter dam of the second side of the first lens barrel satisfy the following condition: 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 polarizer, and the inner diameter dbm of the second side of the second lens barrel satisfy the following condition: 1.94 ≤ fz2 / dbm ≤ 5.

44.

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

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