Visual system

Abstract

The utility model discloses a visual system. The visual system comprises a first lens cone and a second lens cone which are sequentially arranged from a first side to a second side along an optical axis, and a first lens group and a second lens group which are respectively supported on the two lens cones, the first lens group sequentially comprises a first lens, a reflective polarizing element and a quarter-wave plate, and the second lens group sequentially comprises a second lens, a partial reflection element and a third lens; the focal power of the first lens and the second lens is positive, the surface types of the first lens and the third lens are convex and concave-convex respectively, and the second side surface of the second lens is a convex surface; the second lens and the third lens are glued; the second lens group can move along the optical axis to be close to or far away from the display on the second side, so that the system is switched between the first state and the second state; the visual system satisfies 1.11 < = f23 / Dbm < = 3.96 and 6.69 < = (La + Lb) / [Delta] f < = 15.80.

Description

Technical Field

[0001] This application relates to the field of optical devices, and more specifically to a visual system. Background Technology

[0002] With the introduction of the metaverse concept, virtual reality and augmented reality technologies for human-computer interaction have ushered in a second opportunity for development. Visual systems, as a crucial entry point for human-computer interaction, play a key role. Early visual systems primarily used aspherical or Fresnel lenses, which were relatively long, causing the user's center of gravity to shift forward and negatively impacting the user experience.

[0003] The catadioptric optical system represents a significant innovation in visual systems, providing space for the overall design of virtual reality (VR) or augmented reality (AR) devices and becoming a mainstream trend in research and development. By folding the optical path, the catadioptric optical system shortens the overall length of the visual system, thereby shifting the center of gravity of the VR or AR device rearward and enhancing the user experience.

[0004] However, due to significant differences in refractive power among individuals, fixed-focus visual systems are typically only suitable for certain groups of people. Furthermore, ghosting interference can easily occur between lenses, resulting in poor image quality. Utility Model Content

[0005] This application provides a visual system that may include a lens barrel assembly and a lens assembly. The lens barrel assembly includes a first lens barrel and a second lens barrel arranged sequentially from a first side to a second side along the optical axis. The lens assembly includes a first lens assembly and a second lens assembly arranged sequentially from a first side to a second side along the optical axis. The first lens assembly rests against the first lens barrel, and the second lens assembly rests against the second lens barrel. The first lens assembly includes a first lens, a reflective polarizing element, and a quarter-wave plate arranged sequentially from a first side to a second side along the optical axis. The second lens assembly includes a second lens, a partially reflective element, and a third lens arranged sequentially from a first side to a second side along the optical axis. The first lens has positive optical power, with a convex first side and a planar second side. The second lens has positive optical power, with a convex second side. The third lens has either positive or negative optical power, with a concave first side and a convex second side. The second lens and the third lens are cemented together. The second lens group is configured to move along the optical axis to approach or move away from the display located on the second side, enabling the visual system to switch between a first state and a second state. The visual system satisfies the conditions 1.11≤f23 / Dbm≤3.96 and 6.69≤(La+Lb) / Δf≤15.80, where f23 is the combined focal length of the second and third lenses, Dbm is the outer diameter of the second side end face of the second lens barrel, La is the maximum distance on the optical axis from the first side end face to the second side end face of the first lens barrel, Lb is the maximum distance on the optical axis from the first side end face to the second side end face of the second lens barrel, and Δf is the change in effective focal length of the visual system when switching from the first state to the second state.

[0006] In one embodiment, the combined focal length fz of the first lens, the reflective polarizing element, and the quarter-wave plate and the outer diameter Dam of the second side end face of the first lens barrel can satisfy: 2.26≤fz / Dam≤2.50.

[0007] In one embodiment, the effective focal length f1 of the first lens and the maximum distance La on the optical axis from the first side end face of the first lens barrel to the second side end face of the first lens barrel can satisfy: 22.60≤f1 / La≤29.11.

[0008] In one embodiment, the outer diameter Dam of the second side end face of the first lens barrel, the inner diameter das of the first side end face of the first lens barrel, and the center thickness CT1 of the first lens on the optical axis can satisfy: 1.39≤(Dam-das) / CT1≤1.86.

[0009] In one embodiment, the effective focal length f2 of the second lens and the maximum distance Lb on the optical axis from the first side end face to the second side end face of the second lens barrel can satisfy: 11.63≤f2 / Lb≤16.69.

[0010] In one embodiment, the effective focal length f3 of the third lens and the inner diameter dbm of the second side end face of the second lens barrel can satisfy: 2.12≤|f3| / dbm≤4.46.

[0011] In one embodiment, the radius of curvature R1 of the first side surface of the first lens and the outer diameter Das of the first side end face of the first lens barrel can satisfy: 1.30≤R1 / Das≤1.46.

[0012] In one embodiment, the outer diameter Dbs of the first side end face of the second lens barrel and the distance ΔL that the second lens group moves along the optical axis during the process of switching the visual system from the first state to the second state can satisfy: 22.3 <Dbs / ΔL<22.55。

[0013] In one embodiment, the maximum distance Lb between the first side end face and the second side end face of the second lens barrel on the optical axis and the center thickness CT3 of the third lens on the optical axis can satisfy: 2.85 <Lb / CT3<3.2。

[0014] In one embodiment, the center thickness CT2 of the second lens on the optical axis, the outer diameter Dbs of the first side end face of the second lens barrel, and the inner diameter dbs of the first side end face of the second lens barrel can satisfy: 2.15≤CT2 / (Dbs-dbs)≤3.10.

[0015] In one embodiment, the inner diameter dam of the second side end face of the first lens barrel and the distance ΔL that the second lens group moves along the optical axis during the process of switching the visual system from the first state to the second state can satisfy: 18.4 <dam / ΔL<18.7。

[0016] In one embodiment, the outer diameter Dam of the second side end face of the first lens barrel, the inner diameter dam of the second side end face of the first lens barrel, the outer diameter Dbs of the first side end face of the second lens barrel, and the inner diameter dbs of the first side end face of the second lens barrel can satisfy: 1.1 < (Dam - dam) / (Dbs - dbs) < 1.35.

[0017] In one embodiment, the inner diameter dbs of the first side end face of the second lens barrel, the inner diameter dbm of the second side end face of the second lens barrel, and the change in effective focal length Δf of the visual system when switching from the first state to the second state can satisfy: 1.61≤(dbs-dbm) / Δf≤5.70.

[0018] In one embodiment, the entrance pupil diameter EPD of the visual system, the outer diameter Das of the first side end face of the first lens barrel, and the inner diameter Das of the first side end face of the first lens barrel can satisfy: 1.2 <EPD / (Das-das)<1.8。

[0019] The visual system disclosed in this application includes a lens assembly and a lens group. The lens assembly includes a first lens barrel and a second lens barrel arranged sequentially from a first side to a second side along the optical axis. The lens group includes a first lens group and a second lens group arranged sequentially from a first side to a second side along the optical axis. The first lens group rests against the first lens barrel, and the second lens group rests against the second lens barrel. The first lens group includes a first lens, a reflective polarizing element, and a quarter-wave plate arranged sequentially from a first side to a second side along the optical axis. The second lens group includes a second lens, a partially reflective element, and a third lens arranged sequentially from a first side to a second side along the optical axis. The first lens has positive optical power, with a convex first side and a flat second side. The second lens has positive optical power, with a convex second side. The third lens has either positive or negative optical power, with a concave first side and a convex second side. The second lens and the third lens are cemented together. The second lens group is configured to move along the optical axis to approach or move away from a display located on the second side, allowing the visual system to switch between a first state and a second state. By configuring the visual system as described above, and controlling the combined focal length f23 of the second and third lenses and the outer diameter Dbm of the second side end face of the second lens barrel to satisfy the condition 1.11≤f23 / Dbm≤3.96, and the maximum distance La on the optical axis between the first and second side end faces of the first lens barrel and the maximum distance Lb on the optical axis between the first and second side end faces of the second lens barrel, and the change in effective focal length Δf of the visual system when switching from the first state to the second state to satisfy the condition 6.69≤(La+Lb) / Δf≤15.80, the visual system can achieve diopter adjustment from +2D to -5D, while also helping to reduce the influence and interference of ghost images between the first and second lens groups on imaging, ensuring that users can obtain clear images under different visual needs. Attached Figure Description

[0020] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments, taken in conjunction with the accompanying drawings. In the drawings:

[0021] Figure 1 A schematic diagram showing the structure and some parameters of a visual system according to an exemplary embodiment of this application is provided;

[0022] Figure 2 The left and right figures in the figure show the structural schematic diagrams of the visual system according to Embodiment 1 of this application when it is in the first state (+2D state) and the second state (-5D state), respectively;

[0023] Figure 3 The left and right figures in the figure show the structural schematic diagrams of the visual system according to Embodiment 2 of this application when it is in the first state (+2D state) and the second state (-5D state), respectively;

[0024] Figure 4 The left and right figures in the figure show the structural schematic diagrams of the visual system according to Embodiment 3 of this application when it is in the first state (+2D state) and the second state (-5D state), respectively;

[0025] Figure 5 The MTF (Modulation Transfer Function) diagrams of the visual systems according to Embodiments 1, 2 and 3 of this application in the first state (+2D state) are shown.

[0026] Figure 6 The MTF diagrams of the visual systems according to Embodiments 1, 2 and 3 of this application in the second state (-5D state) are shown.

[0027] Figure 7 The left and right figures in the figure show the structural schematic diagrams of the visual system according to Embodiment 4 of this application when it is in the first state (+2D state) and the second state (-5D state), respectively;

[0028] Figure 8 The left and right figures in the figure show the structural schematic diagrams of the visual system according to Embodiment 5 of this application when it is in the first state (+2D state) and the second state (-5D state), respectively;

[0029] Figure 9 The left and right figures in the figure show the structural schematic diagrams of the visual system according to Embodiment 6 of this application when it is in the first state (+2D state) and the second state (-5D state), respectively;

[0030] Figure 10 The MTF diagrams of the visual system according to Embodiments 4, 5 and 6 of this application in the first state (+2D state) are shown.

[0031] Figure 11 The MTF diagrams of the visual system according to Embodiments 4, 5 and 6 of this application in the second state (-5D state) are shown.

[0032] Figure 12 The left and right figures in the figure show the structural schematic diagrams of the visual system according to Embodiment 7 of this application when it is in the first state (+2D state) and the second state (-5D state), respectively;

[0033] Figure 13 The left and right figures in the figure show the structural schematic diagrams of the visual system according to Embodiment 8 of this application when it is in the first state (+2D state) and the second state (-5D state), respectively;

[0034] Figure 14 The left and right figures in the figure show the structural schematic diagrams of the visual system according to Embodiment 9 of this application when it is in the first state (+2D state) and the second state (-5D state), respectively;

[0035] Figure 15 The MTF diagrams of the visual system according to Embodiments 7, 8 and 9 of this application in the first state (+2D state) are shown.

[0036] Figure 16 The MTF diagrams of the visual system according to Embodiments 7, 8 and 9 of this application in the second state (-5D state) are shown.

[0037] Figure 17 A stray light simulation diagram of an exemplary visual system according to this application is shown when the conditions f23 / Dbm = 0.6 and (La+Lb) / Δf = 5.8 are satisfied;

[0038] Figure 18 A stray light simulation diagram of an exemplary visual system according to this application is shown when the conditions f23 / Dbm = 4.6 and (La+Lb) / Δf = 16.5 are satisfied;

[0039] Figure 19 A stray light simulation diagram of an exemplary visual system according to this application is shown when the conditions f23 / Dbm = 1.46 and (La+Lb) / Δf = 8.36 are satisfied. Detailed Implementation

[0040] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0041] 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.

[0042] 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 strictly to scale.

[0043] In this paper, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the 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 the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region.

[0044] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0045] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having a meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formalized sense, unless expressly so specified herein.

[0046] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other. The following embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this application. It should be pointed out that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0047] The features, principles and other aspects of this application are described in detail below.

[0048] A visual system according to an exemplary embodiment of this application may include a lens barrel assembly and a lens assembly. The lens barrel assembly may include a first lens barrel and a second lens barrel; the lens assembly may include a first lens assembly and a second lens assembly. The first lens barrel and the second lens barrel may be arranged sequentially from a first side to a second side along the optical axis; the first lens assembly and the second lens assembly may be arranged sequentially from a first side to a second side along the optical axis.

[0049] In an exemplary embodiment, the first lens group may rest on or be mounted on the first lens barrel; the second lens group may rest on or be mounted on the second lens barrel.

[0050] In an exemplary embodiment, the first lens group may include a first lens, a reflective polarizing element, and a quarter-wave plate. Exemplarily, the first lens, the reflective polarizing element, and the quarter-wave plate may be arranged sequentially from the first side to the second side along the optical axis.

[0051] In an exemplary embodiment, a reflective polarizing element may be disposed on or attached to a second side surface of a first lens; a quarter-wave plate may be disposed on or attached to a second side surface of the reflective polarizing element. Exemplarily, a first side surface of the reflective polarizing element may at least partially adhere to a second side surface of the first lens; a first side surface of the quarter-wave plate may at least partially adhere to a second side surface of the reflective polarizing element.

[0052] In an exemplary embodiment, the second lens group may include a second lens, a partial reflective element, and a third lens. Exemplarily, the second lens, the partial reflective element, and the third lens may be arranged sequentially from the first side to the second side along the optical axis.

[0053] In an exemplary embodiment, the second lens and the third lens can be cemented together to form a cemented lens. Specifically, the second lens, the partial reflective element, and the third lens can be cemented together to form a cemented lens.

[0054] In an exemplary embodiment, the first lens may have positive optical power, its first side surface may be convex, and its second side surface may be planar.

[0055] In an exemplary embodiment, the second lens may have positive optical power, and its first side surface may be convex or concave, while its second side surface may be convex.

[0056] In an exemplary embodiment, the third lens may have positive or negative optical power, and its first side surface may be concave and its second side surface may be convex.

[0057] By rationally configuring the structure of the visual system, optical path reversal can be achieved, effectively shortening the overall length of the visual system, reducing its size and weight, and making it more portable. The use of cemented lenses provides the system with a high-quality lens material, offering advantages such as lightness, good light transmission, and wear resistance, making it more suitable for VR device lens manufacturing and improving lens quality and fit.

[0058] Understandably, along the optical axis, the surface of each element or structure in the visual system that is closer to the first side and farther from the second side can be considered the first side surface of that element or structure, and the surface of each element that is closer to the second side and farther from the first side can be considered the second side surface of that element or structure. The first and second side surfaces of the element or structure can, for example, be perpendicular to the optical axis.

[0059] In an exemplary embodiment, the first side may be, for example, the human eye side, and the second side may be, for example, the display side. The visual system may be used in various VR devices or apparatuses.

[0060] In an exemplary embodiment, the distance on the optical axis between the first lens group (or the first lens group and the first lens barrel) and the display or image surface on the second side of the viewing system can be fixed. The second lens group (or the second lens group and the second lens barrel) can be configured to move along the optical axis to approach or move away from the display or image surface on the second side of the viewing system, thereby switching the viewing system between a first state and a second state. Specifically, when the second lens group (or the second lens group and the second lens barrel) moves to the position closest to the display or image surface, the distance on the optical axis between the second lens group and the first lens group is at its maximum, and the viewing system can be in a +2D state, i.e., the first state; when the second lens group (or the second lens group and the second lens barrel) moves to the position farthest from the display or image surface, the distance on the optical axis between the second lens group and the first lens group is at its minimum, and the viewing system can be in a -5D state, i.e., the second state.

[0061] For example, when the visual system is in the first state, its diopter is +2D, which is suitable for users with a diopter of +2D. When the visual system is in the second state, its diopter is -5D, which is suitable for users with a diopter of -5D. A negative sign for diopter indicates that the user is myopic; a positive sign indicates that the user is hyperopic. The specific value of diopter represents the user's refractive error. For example, +1D diopter indicates that the user's hyperopia is approximately 100 degrees, and -1D diopter indicates that the user's myopia is approximately 100 degrees.

[0062] It should be understood that, in addition to the first and second states, the visual system according to the embodiments of this application may also have other states, for example, between -5D and +2D. The visual system according to the embodiments of this application can achieve continuous zoom within the range of -5D to +2D, meeting the needs of users with different visual acuity, allowing users to enjoy VR experiences without wearing glasses.

[0063] In an exemplary embodiment, the visual system of this application may include at least one aperture stop. The aperture stop can constrain the optical path and control the light intensity. The aperture stop can be set at an appropriate position in the visual system as needed; for example, the aperture stop can be located between a first side (e.g., the human eye side) and a first lens.

[0064] In an exemplary embodiment, the virtual image distance VID of the visual system in the first state and the second state are different. The virtual image distance can be, for example, the distance on the optical axis from the virtual image formed by the image light from the second side at a predetermined position to the aperture. Wherein, VID = 1000 / diopter.

[0065] In an exemplary embodiment, the visual system of this application can satisfy the condition 1.11≤f23 / Dbm≤3.96, where f23 is the combined focal length of the second lens and the third lens, and Dbm is the outer diameter of the second side end face of the second lens barrel. It can be understood that the first side end face of the lens barrel can be the end face or surface of the lens barrel closest to the first side and perpendicular or approximately perpendicular to the optical axis; the second side end face of the lens barrel can be the end face or surface of the lens barrel closest to the second side and perpendicular or approximately perpendicular to the optical axis.

[0066] In an exemplary embodiment, the visual system of this application can satisfy the condition 6.69≤(La+Lb) / Δf≤15.80, where La is the maximum distance on the optical axis from the first side end face of the first lens barrel to the second side end face of the first lens barrel, Lb is the maximum distance on the optical axis from the first side end face of the second lens barrel to the second side end face of the second lens barrel, and Δf is the change in effective focal length of the visual system when switching from +2D state to -5D state.

[0067] A visual system provided according to an exemplary embodiment of this application includes a lens assembly and a lens group. The lens assembly includes a first lens barrel and a second lens barrel arranged sequentially along the optical axis from a first side to a second side. The lens group includes a first lens group and a second lens group arranged sequentially along the optical axis from a first side to a second side. The first lens group rests against the first lens barrel, and the second lens group rests against the second lens barrel. The first lens group includes a first lens, a reflective polarizing element, and a quarter-wave plate arranged sequentially along the optical axis from a first side to a second side. The second lens group includes a second lens, a partially reflective element, and a third lens arranged sequentially along the optical axis from a first side to a second side. The first lens has positive optical power, with a convex first side and a flat second side. The second lens has positive optical power, with a convex second side. The third lens has either positive or negative optical power, with a concave first side and a convex second side. The second lens and the third lens are cemented together. The second lens group is configured to move along the optical axis to approach or move away from a display located on the second side, allowing the visual system to switch between a first state and a second state. By configuring the visual system as described above, and controlling the combined focal length f23 of the second and third lenses and the outer diameter Dbm of the second side end face of the second lens barrel to satisfy the condition 1.11≤f23 / Dbm≤3.96, and the maximum distance La on the optical axis between the first and second side end faces of the first lens barrel and the maximum distance Lb on the optical axis between the first and second side end faces of the second lens barrel, and the change in effective focal length Δf of the visual system when switching from the first state to the second state to satisfy the condition 6.69≤(La+Lb) / Δf≤15.80, the visual system can achieve diopter adjustment from +2D to -5D, while also helping to reduce the influence and interference of ghost images between the first and second lens groups on imaging, ensuring that users can obtain clear images under different visual needs.

[0068] In an exemplary embodiment, the lens group and lens barrel group of the visual system are configured as described above. Furthermore, by setting the two conditional expressions f23 / Dbm and (La+Lb) / Δf to satisfy different numerical ranges, the following three different visual system schemes can be formed:

[0069] In the visual system 1 of the first scheme, the two conditional expressions f23 / Dbm and (La+Lb) / Δf satisfy f23 / Dbm=0.6 and (La+Lb) / Δf=5.8 respectively. It can be seen that the values ​​of both conditional expressions are relatively small, both less than the lower limits of the ranges defined by conditional expressions 1.11≤f23 / Dbm≤3.96 and 6.69≤(La+Lb) / Δf≤15.80 respectively. The stray light simulation diagram of the imaging effect of the visual system 1 is shown below. Figure 17 As shown, by Figure 17It is evident that this system exhibits a significant amount of stray light, such as stray ghost images that are easily generated between the first and second lens groups. Moreover, the intensity of the stray light is relatively high, reaching 4.8E-5, which has a substantial impact on the imaging effect.

[0070] In the second visual system 2, the two conditional expressions f23 / Dbm and (La+Lb) / Δf satisfy f23 / Dbm = 4.6 and (La+Lb) / Δf = 16.5, respectively. It is evident that the values ​​of both conditional expressions are relatively large, exceeding the upper limits of the ranges defined by conditional expressions 1.11≤f23 / Dbm≤3.96 and 6.69≤(La+Lb) / Δf≤15.80, respectively. The stray light simulation diagram of the imaging effect of visual system 2 is shown below. Figure 18 As shown, by Figure 18 It is evident that this system also exhibits a significant amount of stray light. For instance, stray light ghosting is easily generated between the first and second lens groups, and the intensity of the stray light is relatively high, reaching 4.0E-5, which has a substantial impact on the imaging effect.

[0071] In the third visual system 3, the two conditional expressions f23 / Dbm and (La+Lb) / Δf satisfy f23 / Dbm = 1.46 and (La+Lb) / Δf = 8.36, respectively. It can be seen that the values ​​of the two conditional expressions are within the ranges defined by the conditional expressions 1.11≤f23 / Dbm≤3.96 and 6.69≤(La+Lb) / Δf≤15.80, which are reasonable values. The stray light simulation diagram of the imaging effect of this visual system 3 is shown below. Figure 19 As shown, by Figure 19 As can be seen, this scheme produces less stray light, which can effectively reduce stray ghost image interference generated at locations such as between the first and second lens groups. The stray light intensity is also significantly reduced to 1.4E-6, which has little impact on the system's imaging effect and helps to improve the clarity of the image.

[0072] Therefore, the visual system according to this application, through reasonable configuration and control of the system to satisfy the conditions 1.11≤f23 / Dbm≤3.96 and 6.69≤(La+Lb) / Δf≤15.80, can enable the visual system to adjust the diopter from +2D to -5D, while also effectively reducing the interference of stray light ghost images at positions such as between the first lens group and the second lens group on the imaging system, which is conducive to improving the clarity of the image and ensuring that users can obtain clear images under different visual needs.

[0073] In an exemplary embodiment, the combined focal length fz of the first lens, the reflective polarizing element, and the quarter-wave plate and the outer diameter Dam of the second side end face of the first barrel may satisfy: 2.26 ≤ fz / Dam ≤ 2.50. By controlling this conditional expression, ensuring that the conditional ratio does not exceed the upper limit value can guarantee the strength of the first barrel, which is conducive to ensuring the mechanical performance of the module. At the same time, controlling the conditional ratio not to be less than the lower limit value can avoid the module's outer shape being too large and affecting the overall machine volume, which is conducive to ensuring miniaturization.

[0074] In an exemplary embodiment, the effective focal length f1 of the first lens and the maximum distance La on the optical axis from the first side end face of the first barrel to the second side end face of the first barrel may satisfy: 22.60 ≤ f1 / La ≤ 29.11. By controlling this conditional expression, making the conditional ratio not exceed the upper limit value can guarantee the mechanical strength of the first barrel, which is conducive to ensuring the mechanical performance of the module. At the same time, controlling the conditional ratio not to be less than the lower limit value can help ensure that the overall machine thickness does not increase, which is conducive to system miniaturization and, in turn, conducive to ensuring the user experience.

[0075] In an exemplary embodiment, the outer diameter Dam of the second side end face of the first barrel, the inner diameter das of the first side end face of the first barrel, and the central thickness CT1 of the first lens on the optical axis may satisfy: 1.39 ≤ (Dam - das) / CT1 ≤ 1.86. By controlling this conditional expression, making the conditional value not exceed the upper limit value is conducive to ensuring that the outer dimensions of the module are small, which is conducive to the miniaturization of the overall machine. At the same time, controlling the conditional value not to be less than the lower limit value can guarantee the strength of the first barrel, which is conducive to ensuring the mechanical performance of the module.

[0076] In an exemplary embodiment, the inner diameter dam of the second side end face of the first barrel and the distance ΔL that the second lens group moves along the optical axis during the process of the visual system switching from the +2D state to the -5D state may satisfy: 18.4 < dam / ΔL < 18.7. By controlling this conditional expression, making the conditional ratio not exceed the upper limit value is conducive to ensuring that the system can precisely control the gear subdivision during the focusing process within the range from +2D to -5D. At the same time, controlling the conditional ratio not to be less than the lower limit value can guarantee that the extended length of the module will not be too long, thereby ensuring that the maximum thickness of the overall machine will not be too large, which is conducive to system miniaturization and is conducive to improving the user experience.

[0077] In an exemplary embodiment, the effective focal length f2 of the second lens and the maximum distance Lb on the optical axis from the first side end face of the second barrel to the second side end face of the second barrel may satisfy: 11.63 ≤ f2 / Lb ≤ 16.69. By controlling this conditional expression, making the conditional ratio not exceed the upper limit value can guarantee the mechanical strength of the second barrel, which in turn guarantees the mechanical performance of the module. At the same time, controlling the conditional ratio not to be less than the lower limit value can guarantee that the overall machine thickness will not increase, which is conducive to system miniaturization.

[0078] In an exemplary embodiment, the effective focal length f3 of the third lens and the inner diameter dbm of the second side end face of the second barrel may satisfy: 2.12 ≤ |f3| / dbm ≤ 4.46. By controlling this conditional expression, ensuring that the ratio of the conditional expression does not exceed the upper limit value can guarantee that the incidence of effective light is not affected. At the same time, controlling the ratio of the conditional expression not to be less than the lower limit value can ensure that the wall thickness and strength of the second barrel can meet the requirements, which is conducive to ensuring the mechanical performance of the module.

[0079] In an exemplary embodiment, the curvature radius R1 of the first side face of the first lens and the outer diameter Das of the first side end face of the first barrel may satisfy: 1.30 ≤ R1 / Das ≤ 1.46. By controlling this conditional expression, it can be ensured that under the influence of external factors such as vibration or temperature change, the system can always maintain stable imaging performance, reducing problems such as image distortion or blurring caused by lens or barrel deformation.

[0080] In an exemplary embodiment, the outer diameter Dbs of the first side end face of the second barrel and the distance ΔL that the second lens group moves along the optical axis during the process of the visual system switching from the +2D state to the -5D state may satisfy: 22.3 < Dbs / ΔL < 22.55. By controlling this conditional expression, making the ratio of the conditional expression less than the upper limit value can ensure that the shape of the module will not increase to affect the volume of the whole machine, which is conducive to the miniaturization of the system. At the same time, controlling the ratio of the conditional expression to be greater than the lower limit value can ensure the strength of the second barrel, which is conducive to ensuring the mechanical performance of the module.

[0081] In an exemplary embodiment, the maximum distance Lb on the optical axis from the first side end face to the second side end face of the second barrel and the central thickness CT3 of the third lens on the optical axis may satisfy: 2.85 < Lb / CT3 < 3.2. By controlling this conditional expression, making the ratio of the conditional expression less than the upper limit value can ensure the processability of the third lens. At the same time, controlling the ratio of the conditional expression to be greater than the lower limit value can ensure that the thickness of the whole machine will not increase, which is conducive to ensuring the user experience.

[0082] In an exemplary embodiment, the outer diameter Dam of the second side end face of the first barrel, the inner diameter dam of the second side end face of the first barrel, the outer diameter Dbs of the first side end face of the second barrel, and the inner diameter dbs of the first side end face of the second barrel may satisfy: 1.1 < (Dam - dam) / (Dbs - dbs) < 1.35. By controlling this conditional expression, the wall thicknesses of the first barrel and the second barrel can be controlled within a reasonable range, improving the processability of the first barrel and the second barrel.

[0083] In an exemplary embodiment, the inner diameter dbs of the first side end face of the second lens barrel, the inner diameter dbm of the second side end face of the second lens barrel, and the change amount Δf of the effective focal length of the visual system when switching from the +2D state to the -5D state may satisfy: 1.61 ≤ (dbs - dbm) / Δf ≤ 5.70. By controlling this conditional expression, ensuring that the ratio of the conditional expression is less than the upper limit value can ensure that the outer shape of the module will not increase so as to affect the volume of the whole machine, which is beneficial to the miniaturization of the system. At the same time, controlling the ratio of the conditional expression to be greater than the lower limit value can ensure that the strength of the second lens barrel meets the requirements, and thus is beneficial to ensuring the mechanical performance of the module.

[0084] In an exemplary embodiment, the central thickness CT2 of the second lens on the optical axis, the outer diameter Dbs of the first side end face of the second lens barrel, and the inner diameter dbs of the first side end face of the second lens barrel may satisfy: 2.15 ≤ CT2 / (Dbs - dbs) ≤ 3.10. By controlling this conditional expression, ensuring that the ratio of the conditional expression does not exceed the upper limit value can ensure that the thickness of the whole machine will not increase, which is beneficial to ensuring the user experience. At the same time, controlling the ratio of the conditional expression to be not less than the lower limit value can ensure the machinability of the second lens.

[0085] In an exemplary embodiment, the entrance pupil diameter EPD of the visual system, the outer diameter Das of the first side end face of the first lens barrel, and the inner diameter das of the first side end face of the first lens barrel may satisfy: 1.2 < EPD / (Das - das) < 1.8. By controlling this conditional expression, ensuring that the ratio of the conditional expression is less than the upper limit value can prevent too much light from entering the system and avoid generating large amounts of stray light. At the same time, controlling the ratio of the conditional expression to be greater than the lower limit value can ensure that the field angle of the system is within a certain range, and a sufficiently large field angle is beneficial to ensuring the user experience effect.

[0086] On the other hand, the present application also provides a visual system. By arranging a first lens barrel and a second lens barrel in sequence from the first side to the second side along the optical axis, and arranging a first lens group and a second lens group in sequence from the first side to the second side along the optical axis, and setting the first lens group to abut against the first lens barrel and the second lens group to abut against the second lens barrel; further setting the first lens group to include a first lens, a reflective polarizing element, and a quarter-wave plate arranged in sequence from the first side to the second side along the optical axis, and the second lens group to include a second lens, a partially reflective element, and a third lens arranged in sequence from the first side to the second side along the optical axis. Among them, the first lens has a positive optical power, its first side is convex, and its second side is flat; the second lens has a positive optical power, its second side is convex; the third lens has a positive or negative optical power, its first side is concave, and its second side is convex; and the second lens and the third lens are cemented lenses that are cemented to each other; and configuring the second lens group to be able to move along the optical axis to approach or move away from a display located on the second side, so that the visual system can switch between a first state and a second state; at the same time, controlling the combined focal length f23 of the second lens and the third lens and the outer diameter Dbm of the second-side end face of the second lens barrel to satisfy: 1.11 ≤ f23 / Dbm ≤ 3.96, and the inner diameter dam of the second-side end face of the first lens barrel and the distance ΔL that the second lens group moves along the optical axis during the process of the visual system switching from the first state to the second state to satisfy: 18.4 < dam / ΔL < 18.7, can enable the visual system to adjust the diopter between the +2D state and the -5D state, and can accurately control the gear subdivision during the adjustment process to ensure that users can obtain clear images under different visual requirements; at the same time, it can also ensure that the extension length during the movement of the module will not be too long, ensure the miniaturization of the system, and thus is beneficial to improving the user experience.

[0087] The visual system according to the exemplary embodiment of the present application adopts, for example, a three-piece catadioptric architecture. By reasonably setting the system structures such as the lens barrel and the lens group, and reasonably configuring multiple parameters of the system structure and components, it can not only reduce the overall optical length, reduce the system weight, realize the miniaturization and light weight of the system, and improve the user's comfort; but also realize zooming within the range of -5D to +2D through the movement of the second lens group to meet the needs of users with different visual acuities, and users can enjoy the VR experience without wearing glasses; at the same time, it can also effectively reduce the interference of stray light ghost images generated at positions such as between the first lens group and the second lens group, which is beneficial to improving the imaging quality and ensuring that users can obtain clear images under different visual requirements; in addition, the use of cemented lenses in the system has the advantages of being lightweight, good light transmittance, wear resistance, etc., and is more suitable for the manufacture of lenses for VR devices, improving the quality and adaptability of the lenses.

[0088] Furthermore, this application also provides a VR device that may include the visual system provided in any of the above embodiments, wherein the first side may be the human eye side and the second side may be the display / image surface side. This VR device can achieve continuous zoom within the range of -5D to +2D, allowing users with different visual conditions to clearly enjoy the VR experience without wearing glasses. It also features miniaturization, lightweight design, high image quality, and stable performance, thus enhancing the user experience.

[0089] Example 1

[0090] The following is for reference Figure 2 A visual system according to Embodiment 1 of this application is described. Figure 2 The left-middle figure shows a schematic diagram of the visual system according to Embodiment 1 of this application in the first state (+2D state). Figure 2 The figure on the right shows a schematic diagram of the visual system according to Embodiment 1 of this application in the second state (-5D state).

[0091] like Figure 2 As shown, the visual system includes a first lens barrel Pa and a second lens barrel Pb, which are arranged sequentially from the first side to the second side along the optical axis. The visual system also includes a first lens group supported by the first lens barrel Pa and a second lens group supported by the second lens barrel Pb. The first lens group includes a first lens E1, a reflective polarizing element RP and a quarter-wave plate QWP arranged sequentially from the first side to the second side along the optical axis. The second lens group includes a second lens E2, a partially reflective element BS (not shown in the figure) and a third lens E3 arranged sequentially from the first side to the second side along the optical axis.

[0092] In this embodiment, the first lens E1 has positive optical power, its first side surface S3 is convex, and its second side surface S4 is flat. The second lens E2 has positive optical power, its first side surface S13 is convex, and its second side surface S14 is convex. The third lens E3 has negative optical power, its first side surface S14 is concave, and its second side surface S15 is convex. A reflective polarizing element RP is disposed on the second side surface of the first lens E1, and a quarter-wave plate QWP is disposed on the second side surface of the reflective polarizing element RP. The second lens E2 and the third lens E3 are cemented lenses bonded together.

[0093] In this embodiment, the first side can be, for example, the human eye side, and the second side can be, for example, the display side. The second side of the visual system is provided with a display / image surface IMG. The first lens group, including a first lens E1, a reflective polarizing element RP, and a quarter-wave plate QWP, and the first lens barrel Pa, are relatively fixed in distance from the display / image surface IMG along the optical axis. The second lens group, including a second lens E2, a partial reflective element BS, and a third lens E3, and the second lens barrel Pb, can move along the optical axis to approach or move away from the display / image surface IMG. During this process, the visual system can achieve zoom within the range of -5D to +2D. Figure 2 The left-middle figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position closest to the display / image surface IMG. At this time, the visual system is in the +2D state. Figure 2 The middle right figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position furthest from the display / image surface IMG. At this time, the visual system is in the -5D state.

[0094] Table 1 shows the basic parameters of the visual system of Example 1, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0095]

[0096]

[0097] Table 1

[0098] The parameters D1 to D5 in Table 1 can be understood as follows: D5 can be understood as the value along the optical axis from the first side of the filter and / or protective glass IR / CG disposed on the first side of the image plane IMG to the second side of the third lens E3; D4 can be understood as the value along the optical axis from the first side of the second lens E2 to the second side of the quarter-wave plate QWP; D3 can be understood as the value along the optical axis from the second side of the quarter-wave plate QWP to the first side of the second lens E2; D2 can be understood as the value along the optical axis again from the first side of the second lens E2 to the second side of the quarter-wave plate QWP; D1 can be understood as the value of the virtual image distance of the visual system according to this embodiment. During the zooming process achieved by the visual system according to this embodiment through the movement of the second lens group and the second lens barrel Pb along the optical axis, the values ​​of the above parameters D1 to D5 will change accordingly. The visual system in... Figure 2 The +2D state shown in the middle left figure and Figure 2 The values ​​of parameters D1 to D5 under the -5D state shown in the middle right figure are shown in Table 2 below.

[0099] D1 D2 D3 D4 D5 +2D state 500.0000 2.7456 -2.7456 2.7456 1.0000 -5D status -200.0000 0.5194 -0.5194 0.5194 3.2262

[0100] Table 2

[0101] In this embodiment, the first side surface S3 of the first lens E1, the first side surface S13 and the second side surface S14 of the second lens E2, and the first side surface S14 and the second side surface S15 of the third lens E3 are all aspherical surfaces. The surface shape of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0102]

[0103] Where x is the distance vector from the vertex of the aspherical surface at a height of h along the optical axis; c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the reciprocal of the radius of curvature R in Table 2 above); k is the conic coefficient; Ai is the i-th order correction coefficient of the aspherical surface. Table 3 gives the higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for the aspherical surfaces S3 and S13-S15 in Example 1.

[0104] coefficient\surface S3 S13 S14 S15 A4 -1.1105E-06 -1.8981E-06 7.4443E-07 -5.0283E-05 A6 1.0020E-08 -1.8679E-08 -2.6128E-09 1.2222E-07 A8 -3.3669E-11 -1.3839E-11 -8.2786E-12 -1.4558E-10 A10 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A12 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A14 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A18 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A20 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00

[0105] Table 3

[0106] Referring to Table 10, the values ​​of various structural parameters of the visual system according to this embodiment are shown in the 'Embodiment 1' column of Table 10, where das is the inner diameter of the first side end face of the first lens barrel Pa, dam is the inner diameter of the second side end face of the first lens barrel Pa, Das is the outer diameter of the first side end face of the first lens barrel Pa, Dam is the outer diameter of the second side end face of the first lens barrel Pa, dbs is the inner diameter of the first side end face of the second lens barrel Pb, dbm is the inner diameter of the second side end face of the second lens barrel Pb, Dbs is the outer diameter of the first side end face of the second lens barrel Pb, Dbm is the outer diameter of the second side end face of the second lens barrel Pb, La is the maximum distance on the optical axis from the first side end face to the second side end face of the first lens barrel Pa, and Lb is the maximum distance on the optical axis from the first side end face to the second side end face of the second lens barrel Pb. The values ​​of the above structural parameters of the visual system according to this embodiment are consistent in both +2D and -5D focal length states. The units for all parameters shown in Table 10 are millimeters (mm). A schematic diagram of the visual system structure for each parameter can be found in the provided text. Figure 1 .

[0107] Example 2

[0108] The following is for reference Figure 3 A visual system according to Embodiment 2 of this application is described.

[0109] like Figure 3As shown, similar to the visual system in Embodiment 1, the visual system in this embodiment also includes a first lens barrel Pa and a second lens barrel Pb, which are arranged sequentially from the first side to the second side along the optical axis. It also includes a first lens group supported by the first lens barrel Pa and a second lens group supported by the second lens barrel Pb. The first lens group includes a first lens E1, a reflective polarizing element RP and a quarter-wave plate QWP arranged sequentially from the first side to the second side along the optical axis. The second lens group includes a second lens E2, a partial reflective element BS (not shown in the figure) and a third lens E3 arranged sequentially from the first side to the second side along the optical axis.

[0110] Similar to Embodiment 1, in this embodiment, the first side can be, for example, the human eye side, and the second side can be, for example, the display side. A display / image surface IMG is provided on the second side of the visual system. The first lens group, including a first lens E1, a reflective polarizing element RP, and a quarter-wave plate QWP, and the first lens barrel Pa, are relatively fixed in distance from the display / image surface IMG along the optical axis. The second lens group, including a second lens E2, a partial reflective element BS, and a third lens E3, and the second lens barrel Pb, can move along the optical axis to approach or move away from the display / image surface IMG. During this process, the visual system can achieve zoom within the range of -5D to +2D. Figure 3 The left-middle figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position closest to the display / image surface IMG. At this time, the visual system is in the first state (+2D state). Figure 3 The middle right figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position furthest from the display / image surface IMG. At this time, the visual system is in the second state (-5D state).

[0111] The basic parameter table of the visual system in this embodiment is the same as Table 1 in Embodiment 1, the values ​​of parameters D1 to D5 are the same as Table 2 in Embodiment 1, and the table of higher-order coefficients of the aspherical mirror is the same as Table 3 in Embodiment 1.

[0112] The numerical values ​​of the structural parameters of the visual system in this embodiment are shown in the 'Embodiment 2' column of Table 10. The specific descriptions of the meanings represented by each parameter are the same as those in Embodiment 1 above, and will not be repeated here.

[0113] Example 3

[0114] The following is for reference Figure 4 A visual system according to Embodiment 3 of this application is described.

[0115] like Figure 4As shown, similar to the visual system in Embodiment 1, the visual system in this embodiment also includes a first lens barrel Pa and a second lens barrel Pb, which are arranged sequentially from the first side to the second side along the optical axis. It also includes a first lens group supported by the first lens barrel Pa and a second lens group supported by the second lens barrel Pb. The first lens group includes a first lens E1, a reflective polarizing element RP and a quarter-wave plate QWP arranged sequentially from the first side to the second side along the optical axis. The second lens group includes a second lens E2, a partial reflective element BS (not shown in the figure) and a third lens E3 arranged sequentially from the first side to the second side along the optical axis.

[0116] Similar to Embodiment 1, in this embodiment, the first side can be, for example, the human eye side, and the second side can be, for example, the display side. A display / image surface IMG is provided on the second side of the visual system. The first lens group, including a first lens E1, a reflective polarizing element RP, and a quarter-wave plate QWP, and the first lens barrel Pa, are relatively fixed in distance from the display / image surface IMG along the optical axis. The second lens group, including a second lens E2, a partial reflective element BS, and a third lens E3, and the second lens barrel Pb, can move along the optical axis to approach or move away from the display / image surface IMG. During this process, the visual system can achieve zoom within the range of -5D to +2D. Figure 4 The left-middle figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position closest to the display / image surface IMG. At this time, the visual system is in the first state (+2D state). Figure 4 The middle right figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position furthest from the display / image surface IMG. At this time, the visual system is in the second state (-5D state).

[0117] The basic parameter table of the visual system in this embodiment is the same as Table 1 in Embodiment 1, the values ​​of parameters D1 to D5 are the same as Table 2 in Embodiment 1, and the table of higher-order coefficients of the aspherical mirror is the same as Table 3 in Embodiment 1.

[0118] The numerical values ​​of the structural parameters of the visual system in this embodiment are shown in the 'Embodiment 3' column of Table 10. The specific descriptions of the meanings represented by each parameter are the same as those in Embodiment 1 above, and will not be repeated here.

[0119] Figure 5 The MTF curves of the visual systems in Examples 1, 2, and 3 when they are in +2D mode are shown. Figure 6 The MTF curves of the visual systems in Embodiments 1, 2, and 3 are shown when they are in a -5D state. The MTF (Modulation Transfer Function) curve can represent the optical modulation function values ​​corresponding to different spatial frequencies. Figure 5 and Figure 6 As can be seen, the visual systems given in Examples 1, 2 and 3 can achieve good imaging quality in both +2D and -5D focal length states.

[0120] Example 4

[0121] The following is for reference Figure 7 A visual system according to Embodiment 4 of this application is described. Figure 7 The left-middle figure shows a schematic diagram of the visual system according to Embodiment 4 of this application in the first state (+2D state). Figure 7 The figure on the right shows a schematic diagram of the visual system according to Embodiment 4 of this application in the second state (-5D state).

[0122] like Figure 7 As shown, the visual system includes a first lens barrel Pa and a second lens barrel Pb, which are arranged sequentially from the first side to the second side along the optical axis. The visual system also includes a first lens group supported by the first lens barrel Pa and a second lens group supported by the second lens barrel Pb. The first lens group includes a first lens E1, a reflective polarizing element RP and a quarter-wave plate QWP arranged sequentially from the first side to the second side along the optical axis. The second lens group includes a second lens E2, a partially reflective element BS (not shown in the figure) and a third lens E3 arranged sequentially from the first side to the second side along the optical axis.

[0123] In this embodiment, the first lens E1 has positive optical power, its first side surface S3 is convex, and its second side surface S4 is flat. The second lens E2 has positive optical power, its first side surface S13 is convex, and its second side surface S14 is convex. The third lens E3 has positive optical power, its first side surface S14 is concave, and its second side surface S15 is convex. A reflective polarizing element RP is disposed on the second side surface of the first lens E1, and a quarter-wave plate QWP is disposed on the second side surface of the reflective polarizing element RP. The second lens E2 and the third lens E3 are cemented lenses bonded together.

[0124] In this embodiment, the first side can be, for example, the human eye side, and the second side can be, for example, the display side. The second side of the visual system is provided with a display / image surface IMG. The first lens group, including a first lens E1, a reflective polarizing element RP, and a quarter-wave plate QWP, and the first lens barrel Pa, are relatively fixed in distance from the display / image surface IMG along the optical axis. The second lens group, including a second lens E2, a partial reflective element BS, and a third lens E3, and the second lens barrel Pb, can move along the optical axis to approach or move away from the display / image surface IMG. During this process, the visual system can achieve zoom within the range of -5D to +2D. Figure 7The left-middle figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position closest to the display / image surface IMG. At this time, the visual system is in the +2D state. Figure 7 The middle right figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position furthest from the display / image surface IMG. At this time, the visual system is in the -5D state.

[0125] Table 4 shows the basic parameters of the visual system of Example 4, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0126]

[0127]

[0128] Table 4

[0129] According to this embodiment, when the visual system is in the +2D state and the -5D state, the values ​​of parameters D1 to D5 in Table 4 are shown in Table 5 below. The meanings of parameters D1 to D5 can be referred to the description in Embodiment 1.

[0130] D1 D2 D3 D4 D5 +2D state 500.0000 2.7219 -2.7219 2.7219 1.0000 -5D status -200.0000 0.5006 -0.5006 0.5006 3.2213

[0131] Table 5

[0132] In this embodiment, the first side surface S3 of the first lens E1, the first side surface S13 and the second side surface S14 of the second lens E2, and the first side surface S14 and the second side surface S15 of the third lens E3 are all aspherical surfaces. Table 6 gives the higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for each aspherical surface S3 and S13-S15 in Embodiment 4. The aspherical surface shape can be defined by the formula (1) given in Embodiment 1 above.

[0133] coefficient\surface S3 S13 S14 S15 A4 -2.9247E-06 1.2102E-05 2.3863E-06 6.3263E-06 A6 1.6227E-08 -3.2768E-08 -1.5857E-09 -6.2153E-08 A8 -4.0928E-11 -2.2534E-12 -1.1040E-11 6.2266E-11 A10 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A12 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A14 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A18 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A20 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00

[0134] Table 6

[0135] Referring to Table 10, the values ​​of each structural parameter of the visual system in this embodiment are shown in the 'Embodiment 4' column of Table 10. The specific description of the meaning of each parameter is the same as that in Embodiment 1 above, and will not be repeated here.

[0136] Example 5

[0137] The following is for reference Figure 8 A visual system according to Embodiment 5 of this application is described.

[0138] like Figure 8As shown, similar to the visual system in Embodiment 4, the visual system in this embodiment also includes a first lens barrel Pa and a second lens barrel Pb, which are arranged sequentially from the first side to the second side along the optical axis. It also includes a first lens group supported by the first lens barrel Pa and a second lens group supported by the second lens barrel Pb. The first lens group includes a first lens E1, a reflective polarizing element RP and a quarter-wave plate QWP arranged sequentially from the first side to the second side along the optical axis. The second lens group includes a second lens E2, a partially reflective element BS (not shown in the figure) and a third lens E3 arranged sequentially from the first side to the second side along the optical axis.

[0139] Similar to Embodiment 4, in this embodiment, the first side can be, for example, the human eye side, and the second side can be, for example, the display side. A display / image surface IMG is provided on the second side of the visual system. The first lens group, including a first lens E1, a reflective polarizing element RP, and a quarter-wave plate QWP, and the first lens barrel Pa, are relatively fixed in distance from the display / image surface IMG along the optical axis. The second lens group, including a second lens E2, a partial reflective element BS, and a third lens E3, and the second lens barrel Pb, can move along the optical axis to approach or move away from the display / image surface IMG. During this process, the visual system can achieve zoom within the range of -5D to +2D. Figure 8 The left-middle figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position closest to the display / image surface IMG. At this time, the visual system is in the first state (+2D state). Figure 8 The middle right figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position furthest from the display / image surface IMG. At this time, the visual system is in the second state (-5D state).

[0140] The basic parameter table of the visual system in this embodiment is the same as Table 4 in Embodiment 4, the values ​​of parameters D1 to D5 are the same as Table 5 in Embodiment 4, and the table of higher-order coefficients of the aspherical mirror is the same as Table 6 in Embodiment 4.

[0141] The numerical values ​​of the structural parameters of the visual system in this embodiment are shown in the 'Embodiment 5' column of Table 10. The specific descriptions of the meanings represented by each parameter are the same as those in Embodiment 1 above, and will not be repeated here.

[0142] Example 6

[0143] The following is for reference Figure 9 A visual system according to Embodiment 6 of this application is described.

[0144] like Figure 9As shown, similar to the visual system in Embodiment 4, the visual system in this embodiment also includes a first lens barrel Pa and a second lens barrel Pb, which are arranged sequentially from the first side to the second side along the optical axis. It also includes a first lens group supported by the first lens barrel Pa and a second lens group supported by the second lens barrel Pb. The first lens group includes a first lens E1, a reflective polarizing element RP and a quarter-wave plate QWP arranged sequentially from the first side to the second side along the optical axis. The second lens group includes a second lens E2, a partially reflective element BS (not shown in the figure) and a third lens E3 arranged sequentially from the first side to the second side along the optical axis.

[0145] Similar to Embodiment 4, in this embodiment, the first side can be, for example, the human eye side, and the second side can be, for example, the display side. A display / image surface IMG is provided on the second side of the visual system. The first lens group, including a first lens E1, a reflective polarizing element RP, and a quarter-wave plate QWP, and the first lens barrel Pa, are relatively fixed in distance from the display / image surface IMG along the optical axis. The second lens group, including a second lens E2, a partial reflective element BS, and a third lens E3, and the second lens barrel Pb, can move along the optical axis to approach or move away from the display / image surface IMG. During this process, the visual system can achieve zoom within the range of -5D to +2D. Figure 9 The left-middle figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position closest to the display / image surface IMG. At this time, the visual system is in the first state (+2D state). Figure 9 The middle right figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position furthest from the display / image surface IMG. At this time, the visual system is in the second state (-5D state).

[0146] The basic parameter table of the visual system in this embodiment is the same as Table 4 in Embodiment 4, the values ​​of parameters D1 to D5 are the same as Table 5 in Embodiment 4, and the table of higher-order coefficients of the aspherical mirror is the same as Table 6 in Embodiment 4.

[0147] The numerical values ​​of the structural parameters of the visual system in this embodiment are shown in the 'Embodiment 6' column of Table 10. The specific descriptions of the meanings represented by each parameter are the same as those in Embodiment 1 above, and will not be repeated here.

[0148] Figure 10 The MTF curves of the visual systems in Examples 4, 5, and 6 when they are in +2D mode are shown. Figure 11 The MTF curves of the visual systems of Examples 4, 5, and 6 in the -5D state are shown. Figure 10 and Figure 11As can be seen, the visual systems given in Examples 4, 5 and 6 can achieve good imaging quality in both +2D and -5D focal length states.

[0149] Example 7

[0150] The following is for reference Figure 12 A visual system according to Embodiment 7 of this application is described. Figure 12 The left-middle figure shows a schematic diagram of the visual system according to Embodiment 7 of this application in the first state (+2D state). Figure 12 The figure on the right shows a schematic diagram of the visual system according to Embodiment 7 of this application in the second state (-5D state).

[0151] like Figure 12 As shown, the visual system includes a first lens barrel Pa and a second lens barrel Pb, which are arranged sequentially from the first side to the second side along the optical axis. The visual system also includes a first lens group supported by the first lens barrel Pa and a second lens group supported by the second lens barrel Pb. The first lens group includes a first lens E1, a reflective polarizing element RP and a quarter-wave plate QWP arranged sequentially from the first side to the second side along the optical axis. The second lens group includes a second lens E2, a partially reflective element BS (not shown in the figure) and a third lens E3 arranged sequentially from the first side to the second side along the optical axis.

[0152] In this embodiment, the first lens E1 has positive optical power, its first side surface S3 is convex, and its second side surface S4 is flat. The second lens E2 has positive optical power, its first side surface S13 is concave, and its second side surface S14 is convex. The third lens E3 has positive optical power, its first side surface S14 is concave, and its second side surface S15 is convex. A reflective polarizing element RP is disposed on the second side surface of the first lens E1, and a quarter-wave plate QWP is disposed on the second side surface of the reflective polarizing element RP. The second lens E2 and the third lens E3 are cemented lenses bonded together.

[0153] In this embodiment, the first side can be, for example, the human eye side, and the second side can be, for example, the display side. The second side of the visual system is provided with a display / image surface IMG. The first lens group, including a first lens E1, a reflective polarizing element RP, and a quarter-wave plate QWP, and the first lens barrel Pa, are relatively fixed in distance from the display / image surface IMG along the optical axis. The second lens group, including a second lens E2, a partial reflective element BS, and a third lens E3, and the second lens barrel Pb, can move along the optical axis to approach or move away from the display / image surface IMG. During this process, the visual system can achieve zoom within the range of -5D to +2D. Figure 12The left-middle figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position closest to the display / image surface IMG. At this time, the visual system is in the +2D state. Figure 12 The middle right figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position furthest from the display / image surface IMG. At this time, the visual system is in the -5D state.

[0154] Table 7 shows the basic parameters of the visual system of Example 7, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0155]

[0156]

[0157] Table 7

[0158] According to this embodiment, when the visual system is in the +2D state and the -5D state, the values ​​of parameters D1 to D5 in Table 7 are shown in Table 8 below. The meanings of parameters D1 to D5 can be referred to the description in Embodiment 1.

[0159] D1 D2 D3 D4 D5 +2D state 500.0000 3.0597 -3.0597 3.0597 1.0000 -5D status -200.0000 0.8400 -0.8400 0.8400 3.2197

[0160] Table 8

[0161] In this embodiment, the first side surface S3 of the first lens E1, the first side surface S13 and the second side surface S14 of the second lens E2, and the first side surface S14 and the second side surface S15 of the third lens E3 are all aspherical surfaces. Table 9 gives the higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for each aspherical surface S3 and S13-S15 in Embodiment 7. The aspherical surface shape can be defined by the formula (1) given in Embodiment 1 above.

[0162] coefficient\surface S3 S13 S14 S15 A4 -3.0146E-06 1.9696E-05 4.7944E-06 3.9629E-05 A6 2.0191E-08 -4.7456E-08 -4.4489E-09 -1.7519E-07 A8 -4.6596E-11 9.9562E-12 -1.0327E-11 1.9510E-10 A10 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A12 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A14 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A18 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 A20 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00

[0163] Table 9

[0164] Referring to Table 10, the values ​​of each structural parameter of the visual system in this embodiment are shown in the 'Embodiment 7' column of Table 10. The specific description of the meaning of each parameter is the same as that in Embodiment 1 above, and will not be repeated here.

[0165] Example 8

[0166] The following is for reference Figure 13 A visual system according to Embodiment 8 of this application is described.

[0167] like Figure 13As shown, similar to the visual system in Embodiment 7, the visual system in this embodiment also includes a first lens barrel Pa and a second lens barrel Pb, which are arranged sequentially from the first side to the second side along the optical axis. It also includes a first lens group supported by the first lens barrel Pa and a second lens group supported by the second lens barrel Pb. The first lens group includes a first lens E1, a reflective polarizing element RP and a quarter-wave plate QWP arranged sequentially from the first side to the second side along the optical axis. The second lens group includes a second lens E2, a partial reflective element BS (not shown in the figure) and a third lens E3 arranged sequentially from the first side to the second side along the optical axis.

[0168] Similar to Embodiment 7, in this embodiment, the first side can be, for example, the human eye side, and the second side can be, for example, the display side. A display / image surface IMG is provided on the second side of the visual system. The first lens group, including a first lens E1, a reflective polarizing element RP, and a quarter-wave plate QWP, and the first lens barrel Pa, are relatively fixed in distance from the display / image surface IMG along the optical axis. The second lens group, including a second lens E2, a partial reflective element BS, and a third lens E3, and the second lens barrel Pb, can move along the optical axis to approach or move away from the display / image surface IMG. During this process, the visual system can achieve zoom within the range of -5D to +2D. Figure 13 The left-middle figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position closest to the display / image surface IMG. At this time, the visual system is in the first state (+2D state). Figure 13 The middle right figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position furthest from the display / image surface IMG. At this time, the visual system is in the second state (-5D state).

[0169] The basic parameter table of the visual system in this embodiment is the same as Table 7 in Embodiment 7, the values ​​of parameters D1 to D5 are the same as Table 8 in Embodiment 7, and the table of higher-order coefficients of the aspherical mirror is the same as Table 9 in Embodiment 7.

[0170] The numerical values ​​of the structural parameters of the visual system in this embodiment are shown in the 'Embodiment 8' column of Table 10. The specific descriptions of the meanings represented by each parameter are the same as those in Embodiment 1 above, and will not be repeated here.

[0171] Example 9

[0172] The following is for reference Figure 14 A visual system according to Embodiment 9 of this application is described.

[0173] like Figure 14As shown, similar to the visual system in Embodiment 7, the visual system in this embodiment also includes a first lens barrel Pa and a second lens barrel Pb, which are arranged sequentially from the first side to the second side along the optical axis. It also includes a first lens group supported by the first lens barrel Pa and a second lens group supported by the second lens barrel Pb. The first lens group includes a first lens E1, a reflective polarizing element RP and a quarter-wave plate QWP arranged sequentially from the first side to the second side along the optical axis. The second lens group includes a second lens E2, a partial reflective element BS (not shown in the figure) and a third lens E3 arranged sequentially from the first side to the second side along the optical axis.

[0174] Similar to Embodiment 7, in this embodiment, the first side can be, for example, the human eye side, and the second side can be, for example, the display side. A display / image surface IMG is provided on the second side of the visual system. The first lens group, including a first lens E1, a reflective polarizing element RP, and a quarter-wave plate QWP, and the first lens barrel Pa, are relatively fixed in distance from the display / image surface IMG along the optical axis. The second lens group, including a second lens E2, a partial reflective element BS, and a third lens E3, and the second lens barrel Pb, can move along the optical axis to approach or move away from the display / image surface IMG. During this process, the visual system can achieve zoom within the range of -5D to +2D. Figure 14 The left-middle figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position closest to the display / image surface IMG. At this time, the visual system is in the first state (+2D state). Figure 14 The middle right figure shows a schematic diagram of the visual system when the second lens group and the second lens barrel Pb move along the optical axis to the position furthest from the display / image surface IMG. At this time, the visual system is in the second state (-5D state).

[0175] The basic parameter table of the visual system in this embodiment is the same as Table 7 in Embodiment 7, the values ​​of parameters D1 to D5 are the same as Table 8 in Embodiment 7, and the table of higher-order coefficients of the aspherical mirror is the same as Table 9 in Embodiment 7.

[0176] The numerical values ​​of the structural parameters of the visual system in this embodiment are shown in the 'Embodiment 9' column of Table 10. The specific descriptions of the meanings represented by each parameter are the same as those in Embodiment 1 above, and will not be repeated here.

[0177] Figure 15 The MTF curves of the visual systems in Examples 7, 8, and 9 when they are in +2D mode are shown. Figure 16 The MTF curves of the visual systems of Examples 7, 8, and 9 in the -5D state are shown. Figure 15 and Figure 16As can be seen, the visual systems given in Examples 7, 8 and 9 can achieve good imaging quality in both +2D and -5D focal length states.

[0178] Table 10 shows the values ​​of the parameters das, dam, Das, Dam, dbs, dbm, Dbs, Dbm, La, and Lb of the visual system according to embodiments 1-9 above. At least some of these parameters can be configured according to... Figure 1 The measurements were obtained using the annotation method shown, and the units for the parameters listed in Table 10 are all in mm. It should be noted that the values ​​of the above parameters are consistent for the visual systems of each embodiment at both +2D and -5D focal lengths.

[0179] Parameters\Example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 das 35.711 36.004 35.240 35.478 35.259 36.387 35.948 35.802 36.800 dam 41.495 41.558 41.454 40.911 41.038 41.001 40.981 41.157 40.892 Das 42.049 42.278 41.186 41.465 41.849 41.165 41.535 41.791 41.335 Dam 44.315 43.875 43.954 43.731 43.622 43.431 43.801 43.678 43.601 dbs 48.012 48.107 47.957 47.502 47.606 47.442 47.513 47.693 47.407 dbm 44.507 44.670 43.924 44.286 43.993 44.702 44.415 44.269 44.731 Dbs 50.119 50.045 50.156 49.898 49.794 49.598 50.027 49.870 49.827 Dbm 47.980 48.200 47.712 47.759 48.064 47.459 47.888 48.041 47.688 La 3.963 3.763 3.971 4.053 4.141 3.965 4.042 3.963 4.385 Lb 7.220 7.365 7.070 7.229 7.126 7.383 7.229 7.129 7.360

[0180] Table 10

[0181] Furthermore, in Examples 1 to 9, the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, the effective focal length f3 of the third lens, the combined focal length f23 of the second and third lenses, the combined focal length fz of the first lens with the reflective polarizing element and the quarter-wave plate, the entrance pupil diameter EPD of the visual system, the distance ΔL that the second lens group moves along the optical axis during the process of switching the visual system from +2D state to -5D state, and the change in the effective focal length Δf of the visual system during the switch from +2D state to -5D state are shown in Table 11 below.

[0182] Parameters\Example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 f1(mm) 109.56 109.56 109.56 104.23 104.23 104.23 99.12 99.12 99.12 f2 (mm) 85.62 85.62 85.62 105.01 105.01 105.01 118.96 118.96 118.96 f3 (mm) -154.84 -154.84 -154.84 196.29 196.29 196.29 95.04 95.04 95.04 f23(mm) 189.12 189.12 189.12 69.40 69.40 69.40 53.47 53.47 53.47 fz(mm) 109.56 109.56 109.56 104.23 104.23 104.23 99.12 99.12 99.12 EPD (mm) 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 ΔL(mm) 2.23 2.23 2.23 2.22 2.22 2.22 2.22 2.22 2.22 Δf(mm) 0.71 0.71 0.71 1.36 1.36 1.36 1.66 1.66 1.66

[0183] Table 11

[0184] Furthermore, Examples 1 to 9 respectively satisfy the conditions shown in Table 12 below. The visual systems of Examples 1 to 9 correspond to the values ​​of the conditional expressions in Table 12 below at two different focal lengths of +2D and -5D.

[0185] Conditional / Example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 f23 / Dbm 3.94 3.92 3.96 1.45 1.44 1.46 1.12 1.11 1.12 (La+Lb) / Δf 15.80 15.72 15.60 8.31 8.30 8.36 6.79 6.69 7.08 fz / Dam 2.47 2.50 2.49 2.38 2.39 2.40 2.26 2.27 2.27 f1 / La 27.65 29.11 27.59 25.72 25.17 26.29 24.52 25.01 22.60 (Dam-das) / CT1 1.83 1.68 1.86 1.74 1.76 1.48 1.61 1.61 1.39 dam / ΔL 18.64 18.67 18.62 18.42 18.47 18.46 18.46 18.54 18.42 f2 / Lb 11.86 11.63 12.11 14.53 14.74 14.22 16.46 16.69 16.16 |f3| / dbm 3.48 3.47 3.53 4.43 4.46 4.39 2.14 2.15 2.12 R1 / Das 1.43 1.42 1.46 1.38 1.36 1.39 1.31 1.30 1.31 Dbs / ΔL 22.51 22.48 22.53 22.46 22.42 22.33 22.54 22.47 22.45 Lb / CT3 2.99 3.05 2.93 3.12 3.07 3.18 2.90 2.86 2.96 (Dam-dam) / (Dbs-dbs) 1.34 1.20 1.14 1.18 1.18 1.13 1.12 1.16 1.12 (dbs-dbm) / Δf 4.95 4.86 5.70 2.37 2.66 2.02 1.87 2.06 1.61 CT2 / (Dbs-dbs) 2.85 3.10 2.73 2.53 2.77 2.81 2.15 2.48 2.24 EPD / (Das-das) 1.26 1.28 1.35 1.34 1.21 1.67 1.43 1.34 1.76

[0186] Table 12

[0187] This application also provides an imaging device equipped with an electronic photosensitive element for imaging. The electronic photosensitive element can be a charge-coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) device. The imaging device can be a standalone imaging device such as a digital camera, or an imaging module integrated into a mobile electronic device such as a mobile phone. This imaging device is equipped with the visual system described above.

[0188] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the application's concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. Vision system, characterized in that The optical system comprises a lens barrel group and a lens group, wherein, the lens barrel group comprises a first lens barrel and a second lens barrel arranged in sequence along an optical axis from a first side to a second side; the lens group comprises a first lens group and a second lens group arranged in sequence along the optical axis from the first side to the second side; the first lens group is supported by the first lens barrel, and the second lens group is supported by the second lens barrel; the first lens group comprises a first lens, a reflective polarizing element and a quarter-wave plate arranged in sequence along the optical axis from the first side to the second side, and the second lens group comprises a second lens, a partial reflective element and a third lens arranged in sequence along the optical axis from the first side to the second side; wherein the first lens has positive focal power, the first side thereof is a convex surface, and the second side thereof is a flat surface; the second lens has positive focal power, the second side thereof is a convex surface; the third lens has positive focal power or negative focal power, the first side thereof is a concave surface, and the second side thereof is a convex surface; and the second lens and the third lens are cemented together; the second lens group is configured to be movable along the optical axis to approach or move away from a display located at the second side, and to switch the visual system between a first state and a second state; the visual system satisfies: 1.11≤f23 / Dbm≤3.96, 6.69≤(La+Lb) / Δf≤15.80, wherein f23 is the combined focal length of the second lens and the third lens, Dbm is the outer diameter of the second side end surface of the second lens barrel, La is the maximum distance on the optical axis from the first side end surface of the first lens barrel to the second side end surface of the first lens barrel, Lb is the maximum distance on the optical axis from the first side end surface of the second lens barrel to the second side end surface of the second lens barrel, and Δf is the change in effective focal length of the visual system when switched from the first state to the second state.

2. The vision system of claim 1, wherein, the combined focal length fz of the first lens, the reflective polarizing element and the quarter-wave plate satisfies: 2.26≤fz / Dam≤2.

50.

3. The vision system of claim 1, wherein, the effective focal length f1 of the first lens satisfies: 22.60≤f1 / La≤29.

11.

4. The vision system of claim 1, wherein, the outer diameter Dam of the second side end surface of the first lens barrel, the inner diameter das of the first side end surface of the first lens barrel and the central thickness CT1 of the first lens on the optical axis satisfy: 1.39≤(Dam-das) / CT1≤1.

86.

5. The vision system of claim 1, wherein, the effective focal length f2 of the second lens satisfies: 11.63≤f2 / Lb≤16.

69.

6. The vision system of claim 1, wherein, the effective focal length f3 of the third lens satisfies: 2.12≤|f3| / dbm≤4.

46.

7. The vision system of claim 1, wherein, the curvature radius R1 of the first side of the first lens satisfies: 1.30≤R1 / Das≤1.

46.

8. The vision system of claim 1, wherein, An outer diameter Dbs of the first side end surface of the second lens barrel and a distance ΔL of movement of the second lens group along the optical axis during the switching of the visual system from the first state to the second state satisfy: 22.3<Dbs / ΔL<22.

55.

9. The vision system of claim 1, wherein, A maximum distance Lb on the optical axis from the first side end surface of the second lens barrel to the second side end surface of the second lens barrel and a center thickness CT3 of the third lens on the optical axis satisfy: 2.85<Lb / CT3<3.

2.

10. The vision system of claim 1, wherein, A center thickness CT2 of the second lens on the optical axis, an outer diameter Dbs of the first side end surface of the second lens barrel, and an inner diameter dbs of the first side end surface of the second lens barrel satisfy: 2.15≤CT2 / (Dbs-dbs)≤3.

10.

11. The vision system of any one of claims 1 to 10, wherein, An inner diameter dam of the second side end surface of the first lens barrel and a distance ΔL of movement of the second lens group along the optical axis during the switching of the visual system from the first state to the second state satisfy: 18.4<dam / ΔL<18.

7.

12. The vision system of any one of claims 1 to 10, wherein, An outer diameter Dam of the second side end surface of the first lens barrel, an inner diameter dam of the second side end surface of the first lens barrel, an outer diameter Dbs of the first side end surface of the second lens barrel, and an inner diameter dbs of the first side end surface of the second lens barrel satisfy: 1.1<(Dam-dam) / (Dbs-dbs)<1.

35.

13. The vision system of any one of claims 1 to 10, wherein, An inner diameter dbs of the first side end surface of the second lens barrel, an inner diameter dbm of the second side end surface of the second lens barrel, and a change Δf of effective focal length of the visual system during the switching from the first state to the second state satisfy: 1.61≤(dbs-dbm) / Δf≤5.

70.

14. The vision system of any one of claims 1 to 10, wherein, An entrance pupil diameter EPD of the visual system, an outer diameter Das of the first side end surface of the first lens barrel, and an inner diameter das of the first side end surface of the first lens barrel satisfy: 1.2<EPD / (Das-das)<1.8.

Images