Optical system and camera module

Abstract

The present application discloses an optical system and an imaging module. The optical system sequentially includes a first element group, a second element group, and a third element group along the optical axis from the object side to the image side. The first element group includes a first lens with positive optical power, a reflection element, and a second lens with negative optical power. The reflection element is configured to reflect the light rays emitted from the first lens. The optical axis includes a first optical axis and a second optical axis at a preset angle. The reflection element receives the light rays emitted from the first lens along the direction of the first optical axis, and after reflecting the light rays, emits them along the direction of the second optical axis to the second lens. The second element group includes three lenses and is fixed relative to the position of the image plane disposed on the image side. The third element group includes three lenses, and the distance between the third element group and the second element group on the second optical axis is adjustable. The optical system satisfies: 0.6 < d1P / dP2 < 1.1, where d1P is the distance between the object side surface of the first lens and the reflection element along the first optical axis, and dP2 is the distance between the reflection element and the image side surface of the second lens along the second optical axis.

Description

Technical Field

[0001] This application relates to the field of optical devices, and particularly to an optical system and a camera module. Background Art

[0002] With the rapid development of portable devices such as smart phones, telephoto lenses have been widely used due to their advantages of clear imaging of distant objects, large magnification ratio, and ability to present the detailed features of objects.

[0003] The effective focal length of an optical system is an important criterion for measuring whether the optical system is a telephoto lens. The larger the effective focal length of the optical system, the clearer the distant objects photographed by the optical system. However, the effective focal length of the optical system is proportional to the optical path required by the optical system, that is, the larger the effective focal length of the optical system, the larger the optical path required by the optical system. Therefore, in order to achieve the telephoto characteristics of the optical system, the total length of the existing optical systems is usually large, which will severely limit the application of the optical system in portable devices. Summary of the Invention

[0004] One aspect of this application provides such an optical system, which sequentially includes a first element group, a second element group, and a third element group along the optical axis from the object side to the image side. The first element group sequentially includes a first lens with positive optical power, a reflecting element, and a second lens with negative optical power from the object side to the image side. The reflecting element is used to reflect the light rays emitted from the first lens. The second element group includes three lenses. The third element group includes three lenses. The optical axis includes a first optical axis and a second optical axis at a preset angle. The reflecting element receives the light rays emitted from the first lens along the direction of the first optical axis, and reflects the light rays and emits them along the direction of the second optical axis to the second lens. The position of the second element group is fixed relative to the image plane disposed on the image side, and the distance between the third element group and the second element group on the second optical axis is adjustable. The optical system satisfies: 0.6 < d1P / dP2 < 1.1, where d1P is the distance between the object side surface of the first lens and the reflecting element along the first optical axis, and dP2 is the distance between the reflecting element and the image side surface of the second lens along the second optical axis.

[0005] According to an exemplary embodiment of this application, the optical system satisfies: |f1 / f2| ≤ 1.0, where f1 is the effective focal length of the first lens, and f2 is the effective focal length of the second lens.

[0006] According to an exemplary embodiment of this application, the optical system further satisfies: 0.55 ≤ |FG12 / EFL| ≤ 0.67, where FG12 is the combined focal length of the first element group and the second element group, and EFL is the effective focal length of the optical system.

[0007] According to an exemplary embodiment of the present application, the optical system further satisfies: 0.9 < |FG12 / FG3| < 1.1, where FG12 is the combined focal length of the first element group and the second element group, and FG3 is the effective focal length of the third element group.

[0008] According to an exemplary embodiment of the present application, the optical system further satisfies: 15.5 mm < |EFL / (FG12 / FG3)| < 35.0 mm, where FG12 is the combined focal length of the first element group and the second element group, FG3 is the effective focal length of the third element group, and EFL is the effective focal length of the optical system.

[0009] According to an exemplary embodiment of the present application, the optical system further satisfies: 4.2 < D1 / CT1 < 6.6, where D1 is the maximum effective semi-aperture of the first lens, and CT1 is the central thickness of the first lens on the first optical axis.

[0010] According to an exemplary embodiment of the present application, the optical system further satisfies: 2.2 < D2 / CT2 < 6.8, where D2 is the maximum effective semi-aperture of the second lens, and CT2 is the central thickness of the second lens on the second optical axis.

[0011] According to an exemplary embodiment of the present application, the optical system further satisfies: 0.02 mm -1 ≤ D2x / EPDx / d12 ≤ 0.10 mm -1 where D2x is the maximum effective semi-aperture of the second lens in the first direction, EPDx is the entrance pupil diameter of the optical system in the first direction, and d12 is the on-axis distance from the image side of the first lens to the object side of the second lens.

[0012] According to an exemplary embodiment of the present application, the optical system further satisfies: 0.02 mm -1 ≤ D2y / EPDy / d12 ≤ 0.10 mm -1 where D2y is the maximum effective semi-aperture of the second lens in the second direction, EPDy is the entrance pupil diameter of the optical system in the second direction, and d12 is the on-axis distance from the image side of the first lens to the object side of the second lens.

[0013] According to an exemplary embodiment of the present application, the optical system further satisfies: -0.60 < fs1 / fs2 < 1.85, where fs1 is the effective focal length of the object side of the first lens, and fs2 is the effective focal length of the image side of the first lens.

[0014] According to an exemplary embodiment of the present application, the optical system further satisfies: 0.6 < EFL / SL < 0.8, where EFL is the effective focal length of the optical system, and SL is the total length of the optical system along the direction of the second optical axis.

[0015] According to an exemplary embodiment of the present application, the optical system further satisfies: 0.95 ≤ SD1 / SD2 ≤ 1.12, where SD1 is the maximum effective semi-aperture of the lens closest to the object side in the second lens group, and SD2 is the maximum effective semi-aperture of another lens adjacent to the lens closest to the object side in the second lens group.

[0016] According to an exemplary embodiment of the present application, the optical system further satisfies: 0.1 < tan(FOV / 2) < 0.4, where FOV is the maximum field of view angle of the optical system.

[0017] According to an exemplary embodiment of the present application, the optical system further satisfies: OBJmin ≥ 10 cm, where OBJmin is the minimum value of the object distance of the optical system.

[0018] According to an exemplary embodiment of the present application, the reflective element includes a plane mirror.

[0019] According to an exemplary embodiment of the present application, the second lens group includes a third lens with a positive focal power, a fourth lens with a negative focal power, and a fifth lens with a positive focal power, and the third lens group includes a sixth lens with a positive or negative focal power, a seventh lens with a positive focal power, and an eighth lens with a negative focal power.

[0020] Another aspect of the present application provides a camera module, which includes the above-mentioned optical system and an imaging element for converting the optical image formed by the optical system into an electrical signal. Description of the Drawings

[0021] Other features, objectives, and advantages of the present application will become more apparent by reading the detailed description of the non-limiting embodiments with reference to the following drawings. Among them:

[0022] Figure 1A Shows a schematic structural diagram of the optical system according to the present application;

[0023] Figure 1B Shows a schematic diagram of the light path of the light rays in the first lens group;

[0024] Figure 2 Shows a schematic structural diagram of the optical system according to Embodiment 1 of the present application in the first state;

[0025] Figure 3 Shows a schematic structural diagram of the optical system according to Embodiment 1 of the present application in the second state;

[0026] Figure 4A 、 Figure 4B 和 Figure 4CThe axial chromatic aberration curve, the astigmatism curve and the distortion curve are respectively shown when the optical system of Example 1 of the present application is in the first state;

[0027] Figure 5 A schematic structural diagram of an optical system in a first state according to Embodiment 2 of the present application is shown;

[0028] Figure 6 A schematic structural diagram of an optical system in a second state according to Embodiment 2 of the present application is shown;

[0029] Fig. 7A , Figure 7B and Figure 7C The axial chromatic aberration curve, the astigmatism curve and the distortion curve of the optical system of Example 2 of the present application when being in the first state are respectively shown;

[0030] Figure 8 A schematic structural diagram of an optical system in a first state according to Embodiment 3 of the present application is shown;

[0031] Fig. 9 A schematic structural diagram of an optical system in a second state according to Embodiment 3 of the present application is shown;

[0032] Fig. 10A , Fig. 10B and Fig. 10C The axial chromatic aberration curve, the astigmatism curve and the distortion curve of the optical system of Example 3 of the present application when the optical system is in the first state are respectively shown;

[0033] Fig.11 A schematic structural diagram of an optical system in a first state according to Embodiment 4 of the present application is shown;

[0034] Fig.12 shows a schematic structural diagram of an optical system in a second state according to Embodiment 4 of the present application;

[0035] Fig.13A , Fig. 13B and Fig. 13C The axial chromatic aberration curve, the astigmatism curve and the distortion curve of the optical system of Example 4 of the present application in the first state are respectively shown;

[0036] Fig.14 shows a schematic structural diagram of an optical system in a first state according to Embodiment 5 of the present application;

[0037] Fig.15 shows a schematic structural diagram of an optical system in a second state according to Embodiment 5 of the present application;

[0038] Fig.16A , Fig. 16B and Fig. 16CThe axial chromatic aberration curve, the astigmatism curve and the distortion curve of the optical system of Example 5 of the present application in the first state are respectively shown;

[0039] Fig.17 shows a schematic structural diagram of an optical system in a first state according to Embodiment 6 of the present application;

[0040] Fig.18 shows a schematic structural diagram of an optical system in a second state according to Embodiment 6 of the present application;

[0041] Fig.19A , Fig.19B and Fig.19C The axial chromatic aberration curve, the astigmatism curve and the distortion curve of the optical system of Example 6 of the present application when the optical system is in the first state are respectively shown;

[0042] Fig. 20 shows a schematic structural diagram of an optical system in a first state according to Embodiment 7 of the present application;

[0043] Fig.21 shows a schematic structural diagram of an optical system in a second state according to Embodiment 7 of the present application;

[0044] Fig.22A , Fig. 22B and Fig. 22C The axial chromatic aberration curve, the astigmatism curve and the distortion curve of the optical system of Example 7 of the present application in the first state are respectively shown;

[0045] Fig.23 shows a schematic structural diagram of an optical system in a first state according to Embodiment 8 of the present application;

[0046] Fig.24 shows a schematic structural diagram of an optical system in a second state according to Embodiment 8 of the present application;

[0047] Fig.25A , Fig.25B and Fig.25C The axial chromatic aberration curve, the astigmatism curve and the distortion curve of the optical system of Example 8 of the present application in the first state are respectively shown;

[0048] Fig.26 shows a schematic structural diagram of an optical system in a first state according to Embodiment 9 of the present application;

[0049] Fig. 27 shows a schematic structural diagram of an optical system in a second state according to Embodiment 9 of the present application; and

[0050] Fig.28A , Fig.28B and Fig.28CThe axial chromatic aberration curve, the astigmatism curve and the distortion curve are respectively shown when the optical system of Example 9 of the present application is in the first state.

[0051] Illustration Description:

[0052] 10, 100, 200, 300, 400, 500, 600, 700, 800, 900, optical system;

[0053] E1, first lens; E2, second lens; E3, third lens; E4, fourth lens; E5, fifth lens; E6, sixth lens; E7, seventh lens; E8, eighth lens; E9, filter; P, reflective element; STO, aperture; G1, first element group; G2, second element group; G3, third element group; IMA, image plane. DETAILED DESCRIPTION

[0054] In order to better understand the present application, a more detailed description will be made of various aspects of the present application with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of exemplary embodiments of the present application, and do not limit the scope of the present application in any way. Throughout the specification, the same figure numerals refer to the same elements.

[0055] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0056] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are for illustration only and are not drawn strictly to scale.

[0057] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is called the object side of the lens, and the surface of each lens closest to the imaging plane is called the image side of the lens.

[0058] It should also be understood that the terms "including" and / or "having", 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. In addition, when describing the embodiments of the present application, the term "may" is used to mean "one or more embodiments of the present application". And, the term "exemplary" is intended to refer to an example or illustration.

[0059] Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meaning as commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that terms (such as terms defined in commonly used dictionaries) should be interpreted as having the same meaning as their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0060] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0061] The periscope camera module is a common camera module for long-distance shooting. For the optical system in the periscope camera module, the optical system can be provided with a prism, which increases the effective focal length of the periscope camera module by folding the light path, thereby reducing the total length of the periscope camera module while meeting the long focal length shooting requirements, thereby realizing the miniaturization of the periscope camera module.

[0062] Aperture is an important parameter of the periscope camera module, which directly affects the periscope camera module's night scene, snapshot, background blur, video and other functions. For example, a periscope camera module with a large aperture can increase the blurred background of the photo and highlight the subject, while also increasing the shutter speed and focus speed to ensure that the periscope camera module obtains better imaging quality.

[0063] However, the current optical system of the periscope camera module still has some shortcomings. Due to the size restrictions of the light-entering and light-exiting surfaces of the prism, the area of ​​the prism that receives light is limited, which results in less light entering the optical system and a smaller effective aperture of the optical system, resulting in poor dark light effects and blurring effects in the periscope camera module. When the aperture of the periscope camera module becomes larger, the size and weight of the prism will increase accordingly, resulting in an increase in the size and weight of the periscope camera module. It can be seen that the large aperture requirement of the periscope camera module is inconsistent with the miniaturization development trend of the periscope camera module.

[0064] In addition, periscope camera modules usually use motors to drive prisms to move to achieve optical image stabilization. Larger and heavier prisms place higher demands on the thrust of the motors, and larger and heavier prisms take up more space in periscope camera modules, which results in less space available for the motors, affecting the driving effect of the motors. The dual requirements of large driving force and small installation space undoubtedly place higher demands on the motors.

[0065] In order to at least partially solve one or more of the above-mentioned problems and other potential problems, the present application provides an optical system. Specifically, it provides an optical system that reduces the overall height and overall length of the optical system while achieving a large aperture of the optical system, and improves the imaging quality and optical image stabilization performance of the optical system.

[0066] Figure 1A The schematic diagram of the structure of the optical system according to the present application is shown. The optical system can be applied to a camera module, for example, and the camera module can be a periscope camera module. It should be understood that the optical system can also be applied to other camera modules, and the present application does not make specific restrictions on this.

[0067] refer to Figure 1A , the optical system 10 may include a first element group G1, a second element group G2 and a third element group G3 in order from the object side to the image side along the optical axis. The first element group G1 may include a first lens E1, a reflective element P and a second lens E2. The first lens E1 may have a positive optical power. The reflective element P may be used to reflect the light emitted from the first lens E1. The second lens E2 may have a negative optical power. The second element group G2 may include at least one lens. The third element group G3 may include at least one lens. An image plane IMA may be provided on the image side of the optical system 10.

[0068] The first lens E1 converges the light, so that the light remains in a converged state after being reflected by the reflective element P, and the number of light rays entering the second lens E2 is increased, thereby increasing the effective aperture of the optical system 10, improving the imaging quality of the optical system 10, and also reducing the effective aperture of the lens in the rear element group (for example, the second element group G2 and the third element group G3), reducing the shoulder height of the rear element group, and thus reducing the overall height of the optical system 10. At the same time, the optical anti-shake performance of the optical system 10 can be improved by using the second lens E2.

[0069] In an exemplary embodiment, reference Figure 1A, the reflective element P is arranged at any desired angle to bend the optical path. The reflective element P may be arranged to deflect the incident optical path by a preset degree (for example, but not limited to 90°), for example, to make the incident optical path change from propagating along the first optical axis (abbreviated as, optical axis I) to propagating along the second optical axis (abbreviated as, optical axis II). It should be understood that the optical axis herein may include the first optical axis and the second optical axis at a preset angle.

[0070] In an exemplary embodiment, reference Figure 1A , the reflective element P may be disposed between the first lens E1 and the second lens E2. That is, the first lens E1 may be located on the optical axis I and disposed between the object side and the reflective element P, and the second lens E2 may be located on the optical axis II and disposed between the reflective element P and the second element group G2. The reflective element P may receive the light emitted from the first lens E1 along the direction of the optical axis I, and reflect the light and emit it into the second lens E2 along the direction of the optical axis II. The optical axis I and the optical axis II are at a preset angle, for example but not limited to, the optical axis I is perpendicular to the optical axis II.

[0071] In an exemplary embodiment, reference Figure 1A , the reflective element P may be a plane reflector, and the plane reflector may have a reflective surface. The light emitted from the first lens E1 in the direction of the optical axis I is totally reflected by the reflective surface of the reflective element P and is emitted into the second lens E2 in the direction of the optical axis II. The reflective surface of the reflective element P passes through the intersection of the optical axis I and the optical axis II, that is, the reflective surface of the reflective element P is located on both the optical axis I and the optical axis II. By adopting a plane reflector of smaller weight and size as the reflective element, when the optical system 10 realizes a large aperture, the weight and size of the first element group G1 can be constrained within a certain range, the weight and size of the optical system 10 can be reduced as much as possible, and the driving burden of the reflective element P can be reduced.

[0072] It should be understood that the plane reflector only has a reflective surface, and its position facing the light incident side and the light exit side is empty. When the first lens E1 is set, the first lens E1 can be made closer to the plane reflector, reducing the height space occupied by the first lens E1 and the reflective element P, thereby reducing the overall height of the optical system 10.

[0073] In an exemplary embodiment, the first lens E1 may have a positive focal length and is used to converge light. By making the first lens E1 have a convergence effect on light, the light can remain in a convergence state after being reflected by the reflective element P, increasing the amount of light entering the second lens E2, and increasing the effective aperture (i.e., the amount of light entering) of the optical system 10 without changing the physical aperture of the aperture STO. In other words, under the same light conditions, the optical system 10 can capture more light, thereby improving the brightness of the image formed by the optical system 10. For example, in a dark environment, an optical system 10 with a large aperture can capture more light, which is particularly important for improving the imaging quality of the optical system 10 and the camera module including the optical system 10 in a dark environment.

[0074] At the same time, the first lens E1 converges the light, and the converged light is still in a converged state after being reflected by the reflective element P, which is conducive to reducing the effective aperture of the second lens E2, and the aperture of the light emitted from the second lens E2 when entering the second element group G2 will still be smaller than the aperture of the light when entering the first lens E1, reducing the effective aperture of the lens in the rear-end element group (for example, the second element group G2 and the third element group G3), thereby reducing the shoulder height of the rear-end element group. It should be understood that when the camera module including the optical system 10 is applied to an electronic device, the shoulder height of the rear-end element group will affect the thickness of the electronic device. Therefore, reducing the shoulder height of the rear-end element group is conducive to reducing the thickness of the electronic device and meeting the design requirements of miniaturization.

[0075] In addition, relative to parallel light, the reflection point of the light after being converged by the first lens E1 at the outermost position on the reflective element P is closer to the optical axis, which makes the reflective element P smaller, further reduces the height of the reflective element P, and reduces the overall height of the optical system 10.

[0076] In an exemplary embodiment, the second lens E2 may have a negative optical power and expand the light reflected by the reflective element P. By making the second lens E2 expand the light, the light emitted from the second lens E2 can be incident on the second element group G2 in a direction close to being parallel to the optical axis II, that is, the light at each position of the edge propagates in a direction close to being parallel to the optical axis II, ensuring that the effective aperture of the lens in the rear element group (for example, the second element group G2 and the third element group G3) is relatively close to the effective aperture of the second lens E2. Under the convergence effect of the first lens E1 on the light, the effective aperture of the lens in the rear element group can be further reduced, thereby reducing the shoulder height of the rear element group.

[0077] At the same time, by setting the second lens E2 and making the second lens E2 have a beam expansion effect on the light, when the reflective element P is driven to achieve optical image stabilization, the movement of the reflective element P has a small effect on the position of the light on the second element group G2, and the MTF drop value of the optical system 10 is small, that is, the anti-shake sensitivity is low. Specifically, the second lens E2 expands the light, which can increase the coverage area of ​​the light in the second element group G2, and the pre-diffused light is not all concentrated in a very small area. Therefore, even if the reflective element P moves during the optical image stabilization operation, these movements have a relatively small effect on the position of the light in the second element group G2, and the MTF drop value of the optical system 10 is small, that is, the anti-shake sensitivity is low.

[0078] If the second lens E2 has no optical power or has positive optical power, the light reflected by the reflective element P directly reaches the second element group G2, and the light is still in a state of converging toward the center when reaching the second element group G2, which makes the coverage area of ​​the light reaching the second element group G2 smaller. In this case, the light reaching the second element group G2 is relatively concentrated, and if the reflective element P moves during the optical image stabilization operation, these movements will have a greater impact on the position of the light in the second element group G2, resulting in a larger drop value of the MTF of the optical system 10, that is, a higher image stabilization sensitivity.

[0079] In an exemplary embodiment, there may be a spacing distance between the first lens E1 and the reflective element P. There may be a spacing distance between the second lens E2 and the reflective element P. By providing a spacing between the first lens E1, the second lens E2 and the reflective element P, multiple options can be provided for the surface design of the side surface of the first lens E1 and the second lens E2 close to the reflective element P, thereby improving the flexibility of the surface design of the side surface of the first lens E1 and the second lens E2 close to the reflective element P.

[0080] It should be understood that the spacing distance between the first lens E1 and the reflective element P means that a surface of one side of the first lens E1 close to the reflective element P has a certain gap with at least a portion of the reflective element P, rather than the first lens E1 is completely non-contacting with the reflective element P. Similarly, the spacing distance between the second lens E2 and the reflective element P means that a surface of one side of the second lens E2 close to the reflective element P has a certain gap with at least a portion of the reflective element P, rather than the second lens E2 is completely non-contacting with the reflective element P.

[0081] In an exemplary embodiment, at least one surface of the first lens E1 and / or the second lens E2 is an aspherical surface. The characteristic of an aspherical lens is that the curvature changes continuously from the center of the lens to the periphery of the lens. Unlike a spherical lens having a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has a better curvature radius characteristic, and has the advantages of improving distortion aberration and improving astigmatism aberration. After using an aspherical lens, the aberration occurring during imaging can be eliminated as much as possible, thereby improving the imaging quality.

[0082] As an example, the object-side surface of the first lens E1 may be a convex surface, and the image-side surface may be a convex surface or a concave surface.

[0083] As an example, the object-side surface of the second lens E2 may be a convex surface or a concave surface, and the image-side surface may be a convex surface or a concave surface.

[0084] In an exemplary embodiment, reference Figure 1A The second element group G2 may include three lenses, for example, a third lens E3, a fourth lens E4, and a fifth lens E5 arranged in sequence from the object side to the image side. The third lens E3, the fourth lens E4, and the fifth lens E5 may be arranged in sequence from the second lens E2 to the image side along the optical axis II.

[0085] As an example, the third lens E3 may have positive refractive power. The fourth lens E4 may have negative refractive power. The fifth lens E5 may have positive refractive power.

[0086] As an example, the second element group G2 may further include a stop STO, which may be disposed, for example, between the second lens E2 and the third lens E3.

[0087] It should be understood that the number of lenses included in the second element group G2 being three is merely exemplary, and the present application does not impose any specific limitation on the number of lenses included in the second element group G2.

[0088] In an exemplary embodiment, reference Figure 1A The third element group G3 may include three lenses, for example, a sixth lens E6, a seventh lens E7, and an eighth lens E8 arranged in sequence from the object side to the image side. The sixth lens E6, the seventh lens E7, and the eighth lens E8 may be arranged in sequence from the fifth lens E5 to the image side along the optical axis II.

[0089] As an example, the sixth lens E6 may have positive power or negative power. The seventh lens E7 may have positive power. The eighth lens E8 may have negative power.

[0090] It should be understood that the number of lenses included in the third element group G3 being three is merely exemplary, and the present application does not impose any specific limitation on the number of lenses included in the third element group G3.

[0091] In an exemplary embodiment, reference Figure 1A The optical system 10 may further include a filter E9. The filter E9 may be disposed on the image side of the third element group G3 and is used to filter the light emitted from the third element group G3. The filter E9 may be, for example, an infrared filter.

[0092] In an exemplary embodiment, reference Figure 1A When light enters the optical system 10, first, the light enters the first lens E1 along the direction of the optical axis I and reaches the reflective element P after being converged by the first lens E1, and then is totally reflected by the reflective element P and turns to enter the second lens E2 along the direction of the optical axis II; then, the light emitted from the second lens E2 enters the second element group G2 and the third element group G3, and passes through the third lens E3, the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7, and the eighth lens E8 in sequence, and reaches the filter E9, and finally reaches the image plane IMA after passing through the filter E9.

[0093] By adopting the first lens E1, the reflective element P and the second lens E2, the aperture of the optical system 10 can be increased, so that the optical system 10 can obtain higher image brightness, and the imaging quality and optical anti-shake performance of the optical system 10 are improved, while the weight and size of the optical system 10 can be reduced.

[0094] In an exemplary embodiment, reference Figure 1A , the second element group G2 can be fixed relative to the image plane IMA on the optical axis (such as optical axis II). The third element group G3 can move relative to the second element group G2 along the optical axis (such as optical axis II), that is, the distance between the third element group G3 and the second element group G2 on the optical axis (such as optical axis II) is adjustable. When the distance between the object and the optical system 10 changes from far to near, the distance between the third element group G3 and the second element group G2 on the optical axis (such as optical axis II) can be adjusted to enable the optical system 10 to switch between the first state and the second state, thereby realizing the focusing function of the optical system 10. For example, when the distance between the object and the optical system 10 is infinite, the optical system 10 is in the first state (such as the long-distance state); when the distance between the object and the optical system 10 is a preset value, the optical system 10 is in the second state (such as the short-distance state). By making the second element group G2 a fixed group element group and the third element group G3 a dynamic group element, the stroke of the motor can be shortened during the focusing process of the optical system 10, thereby improving the imaging quality of the optical system 10. As an example, the first element group G1 may be fixed in position relative to the image plane IMA on an optical axis (eg, optical axis II).

[0095] In an exemplary embodiment, reference Figure 2 and Figure 3When the distance between the object and the optical system 10 changes from far to near, the third element group G3 can move along the optical axis II in a direction away from the second element group G2, so that the optical system 10 switches from the first state to the second state. When the distance between the object and the optical system 10 changes from near to far, the third element group G3 can move along the optical axis II in a direction close to the second element group G2, so that the optical system 10 switches from the second state to the first state.

[0096] In an exemplary embodiment, during the focusing process of the optical system 10 , the maximum movement stroke of the third element group G3 may be in the range of 1.0 mm to 7.0 mm.

[0097] In an exemplary embodiment, the optical system 10 may further include a barrel assembly (not shown). The barrel assembly may include a first barrel, a second barrel, and a third barrel. The first element group G1 may be fixed in the first barrel. The second element group G2 may be fixed in the second barrel. The third element group G3 may be fixed in the third barrel. The first barrel has a first opening on the light incident side and a second opening on the light exit side, the first lens E1 is disposed in the first opening, the second lens E2 is disposed in the second opening, and the reflective element P is disposed between the first opening and the second opening, wherein the inner diameter of the first opening is greater than the inner diameter of the second opening; or, the inner diameter of the first opening is equal to the inner diameter of the second opening. The inner diameters of the parts corresponding to different lenses in the second barrel are different. The inner diameters of the parts corresponding to different lenses in the third barrel are different.

[0098] During the focusing process of the optical system 10, the second lens barrel and the second element group G2 may be fixed relative to the image plane IMA on the optical axis II, and the third lens barrel and the third element group G3 may move along the optical axis II in a direction away from the second element group G2, or the third lens barrel and the third element group G3 may move along the optical axis II in a direction close to the second element group G2. It should be understood that when the optical system 10 implements the focusing function, the third lens barrel and the third element group G3 may be driven by a motor (not shown) to move along the optical axis II, and the second lens barrel and the second element group G2 do not move. As an example, the first lens barrel and the first element group G1 are fixed relative to the image plane IMA on the optical axis II.

[0099] In an exemplary embodiment, the optical system 10 may further include a barrel assembly (not shown). The second element group G2 may be fixed in the barrel assembly. The third element group G3 may be movably arranged in the barrel assembly. During the focusing process of the optical system 10, the barrel assembly and the second element group G2 may be fixed relative to the position of the image plane IMA on the optical axis II, and the third element group G3 may move along the optical axis II in a direction away from the second element group G2, or the third element group G3 may move along the optical axis II in a direction close to the second element group G2. It should be understood that when the optical system 10 realizes the focusing function, the third element group G3 may be driven by a motor (not shown) to move along the optical axis II, and the barrel assembly and the second element group G2 may not move. As an example, the first element group G1 may be fixed in the barrel assembly.

[0100] In an exemplary embodiment, when light enters the optical system 10, due to the convergence effect of the first lens E1 on the light, the light is in a convergence state after being emitted from the first lens E1, and after being reflected by the reflective element P, it still reaches the second lens E2 in the same convergence state. However, due to the expansion effect of the second lens E2 on the light, the convergence angle of the light after being emitted from the second lens E2 will decrease (for example, the convergence angle of the light after being emitted from the second lens E2 is less than the convergence angle of the light from the first lens E1), and at the same time, the gap between the second lens E2 and the third lens E3 is small, so the effective aperture of the third lens E3 is relatively close to the effective aperture of the second lens E2, for example, the effective aperture of the third lens E3 is slightly smaller than the effective aperture of the second lens E2. The shoulder height of the rear element group (for example, the second element group G2 and the third element group G3) is usually related to the maximum effective aperture of the third lens E3 in the second direction, or, is related to the maximum aperture diameter of the stop STO in the second direction.

[0101] Figure 1B Schematic diagram of the optical path of light in the first element group is shown. It should be noted that, for the sake of convenience, Figure 1B The reflective element P is omitted, and the first lens E1 is transposed to the optical axis II. The actual structure diagram of the first element group should be similar to Figure 1A .

[0102] As an example, refer to Figure 1A and Figure 1B, the optical system 10 can satisfy: 0.1 < tan(α) × d12 < 1.8, where α is the angle between the outgoing light ray B1 corresponding to the first lens E1 and the incoming light ray A1 corresponding to the first lens E1 (i.e., the light convergence angle of the first lens E1), the incoming light ray A1 corresponding to the first lens E1 can be, for example, a parallel light ray, and d12 is the on-axis distance from the image side surface of the first lens E1 to the object side surface of the second lens E2. The product of tan(α) and d12 is approximately equal to the difference in the maximum effective semi-apertures of the first lens E1 and the second lens E2. The larger the value of α, the better the light convergence effect of the first lens E1, and the larger the difference in the maximum effective semi-apertures of the first lens E1 and the second lens E2. By restricting tan(α) × d12 within the range of 0.1 to 1.8, the first lens E1 can have a strong light convergence ability, ensuring that the light remains in a converging state after being reflected by the reflecting element P, which is beneficial to reducing the effective aperture of the second lens E2, and further reducing the effective apertures of the lenses within the rear-end element group (for example, the second element group G2 and the third element group G3), reducing the shoulder height of the rear-end element group, reducing the total height of the optical system 10, and at the same time, being beneficial to achieving a large aperture of the optical system 10.

[0103] Parameters such as the total height, total length, anti-shake sensitivity, and aperture number of the optical system 10 are mutually restrictive. If the value of tan(α) × d12 is less than 0.1, it will result in a poor light convergence effect of the first lens E1, thereby causing too small a difference in the maximum effective semi-apertures of the first lens E1 and the second lens E2, too large a shoulder height of the rear-end element group, and too large a total height of the optical system 10. If the value of tan(α) × d12 is greater than 1.8, it will result in too high an anti-shake sensitivity of the optical system 10 (for example, the anti-shake sensitivity is about 10%), which cannot meet the design requirement of an anti-shake sensitivity of 5%; or, it will cause too high a total length of the optical system 10.

[0104] As an example, refer to Figure 1A and Figure 1B, the optical system 10 may satisfy: 0.1 < tan(α)×d12 + tan(β)×d23 < 1.8, where α is the angle between the outgoing light ray B1 corresponding to the first lens E1 and the incoming light ray A1 corresponding to the first lens E1 (i.e., the light beam convergence angle of the first lens E1), β is the angle between the outgoing light ray B2 corresponding to the second lens E2 and the incoming light ray A1 corresponding to the first lens E1, the incoming light ray A1 corresponding to the first lens E1 may be, for example, a parallel light ray, d12 is the axial distance from the image side surface of the first lens E1 to the object side surface of the second lens E2, and d23 is the axial distance from the image side surface of the second lens E2 to the object side surface of the third lens E3. The product of tan(α) and d12 is approximately equal to the difference between the maximum effective semi-apertures of the first lens E1 and the second lens E2. The larger the value of α, the better the light beam convergence effect of the first lens E1, and the larger the difference between the maximum effective semi-apertures of the first lens E1 and the second lens E2. The product of tan(β) and d23 is approximately equal to the difference between the maximum effective semi-apertures of the second lens E2 and the third lens E3. On the basis of not affecting the anti-shake performance, by adjusting the beam expansion ability of the second lens E2, it is possible to make there still be a certain angle between the light beam expanded by the second lens E2 and the optical axis II, so as to reduce the shoulder height of the rear element group (for example, the second element group G2 and the third element group G3). By constraining tan(α)×d12 + tan(β)×d23 within the range of 0.1 to 1.8, the first lens E1 can have a strong light beam convergence ability, ensuring that the light beam remains in a converging state after being reflected by the reflecting element P, which is beneficial to reducing the effective aperture of the second lens E2. At the same time, the beam expansion ability of the second lens E2 is weak, which can further reduce the effective aperture of the third lens E3, reduce the shoulder height of the rear element group, and reduce the total height of the optical system 10.

[0105] In an exemplary embodiment, referring to Figure 1A, the optical system 10 may satisfy: 1.1<(d1P+dP2) / SH<1.6, wherein d1P is the on-axis distance from the object side surface of the first lens E1 to the reflective element P (for example, the distance between the object side surface of the first lens E1 and the reflective element P along the optical axis I), dP2 is the on-axis distance from the reflective element P to the image side surface of the second lens E2 (for example, the distance between the reflective element P and the image side surface of the second lens E2 along the optical axis II), and SH is the total height of the optical system 10. d1P and dP2 are related to the light convergence capability of the first element group G1. Generally speaking, the larger the value of d1P+dP2 is, the stronger the light convergence capability of the first element group G1 is. By controlling (d1P+dP2) / SH to be within the range of 1.1 to 1.6, it is helpful to ensure that the first element group G1 has a good light focusing ability, and reasonably arrange the positions of the first lens E1, the reflective element P and the second lens E2 to avoid interference between the reflective element P and the first lens E1 and the second lens E2; at the same time, the total height of the optical system 10 can be reduced when the total length of the optical system 10 meets the design requirements and the reflective element P does not interfere with the first lens E1 and the second lens E2. Further, 2.9mm <d1P<10.4mm。

[0106] When the value of (d1P+dP2) / SH is less than 1.1, the value of d1P+dP2 is too small, resulting in poor light convergence ability of the first element group G1, and the shoulder height of the rear element group and the total height of the optical system 10 are too large; or, when the value of (d1P+dP2) / SH is less than 1.1, the value of SH is too large, resulting in the total height of the optical system 10 being too large. When the value of (d1P+dP2) / SH is greater than 1.6, the value of d1P+dP2 is too large, resulting in the total length of the optical system 10 being too large. The total height of the optical system 10 and the total length of the optical system 10 are mutually constrained. By controlling (d1P+dP2) / SH to be within the range of 1.1 to 1.6, it is beneficial to reduce the total height and total length of the optical system 10.

[0107] In an exemplary embodiment, reference Figure 1A, the optical system 10 can satisfy: 0.1 < dP2 / SL < 0.3, where dP2 is the on-axis distance from the reflection element P to the image side surface of the second lens E2 (for example, the distance between the reflection element P and the image side surface of the second lens E2 along the optical axis II), and SL is the total length of the optical system 10 in the direction where the second optical axis is located. By controlling dP2 / SL to be within the range of 0.1 to 0.3, when the total length of the optical system 10 meets the design requirements, it is beneficial to ensure that the first element group G1 has a good light converging effect, reduce the shoulder height of the rear element group (for example, the second element group G2 and the third element group G3), and thus reduce the total height of the optical system 10. d1P, dP2 are related to the light converging ability of the first element group G1. The larger the value of d1P + dP2, the stronger the light converging ability of the first element group G1. When the value of d1P + dP2 is fixed, if the value of dP2 becomes larger, the value of d1P becomes smaller, which is beneficial to reducing the shoulder height of the rear element group and the total height of the optical system 10 while ensuring that the first element group G1 has a good light converging effect.

[0108] When the value of dP2 / SL is less than 0.1, the value of dP2 is too small, and the value of d1P + dP2 is too small, resulting in a poor light converging ability of the first element group G1, a too large shoulder height of the rear element group, and a too large total height of the optical system 10; or, when the value of dP2 / SL is less than 0.1, the value of dP2 is too small, and the value of d1P is too large, resulting in a too large total height of the optical system 10. When the value of dP2 / SL is greater than 0.3, the value of dP2 is too large, resulting in a too large total length of the optical system 10. The total height and the total length of the optical system 10 restrict each other. By controlling dP2 / SL to be within the range of 0.1 to 0.3, it is beneficial to reduce the total height and the total length of the optical system 10.

[0109] In an exemplary embodiment, the optical system 10 can satisfy: 0.6 < d1P / dP2 < 1.1, where d1P is the on-axis distance from the object side surface of the first lens E1 to the reflection element P (for example, the distance between the object side surface of the first lens E1 and the reflection element P along the optical axis I), and dP2 is the on-axis distance from the reflection element P to the image side surface of the second lens E2 (for example, the distance between the reflection element P and the image side surface of the second lens E2 along the optical axis II). By controlling d1P / dP2 to be within the range of 0.6 to 1.1, when the total length of the optical system 10 meets the design requirements, it is beneficial to ensure that the first element group G1 has a good light converging effect, and reasonably allocate the values of d1P and dP2, reduce the shoulder height of the rear element group (for example, the second element group G2 and the third element group G3), and reduce the total height of the optical system 10.

[0110] When the value of d1P / dP2 is less than 0.6, the value of dP2 is too large, resulting in an excessively large total length of the optical system 10. When the value of d1P / dP2 is greater than 1.1, the value of dP2 is too small, and the value of d1P+dP2 is too small, resulting in poor light convergence capability of the first element group G1, excessive shoulder height of the rear element group and excessive total height of the optical system 10; or, when the value of d1P / dP2 is greater than 1.1, the value of d1P is too large, resulting in an excessively large total height of the optical system 10. The total height of the optical system 10 and the total length of the optical system 10 are mutually constrained. By controlling d1P / dP2 to be within the range of 0.6 to 1.1, it is beneficial to reduce the total height and total length of the optical system 10.

[0111] In an exemplary embodiment, the optical system 10 may satisfy: |f1 / f2|≤1.0, where f1 is the effective focal length of the first lens E1, and f2 is the effective focal length of the second lens E2. Reasonable configuration of the effective focal length ratio of the first lens E1 to the second lens E2 can make the first lens E1 have a strong convergence ability for light, a strong effect on expanding the aperture, and ensure that the light is still in a convergence state after being reflected by the reflective element P, which is conducive to reducing the effective aperture of the second lens E2, thereby reducing the effective aperture of the lens in the rear element group (for example, the second element group G2 and the third element group G3), reducing the shoulder height of the rear element group, and reducing the overall height of the optical system 10; at the same time, it can also make the angle between the light emitted by the second lens E2 and the optical axis II within a smaller range, thereby improving the optical anti-shake performance of the optical system 10.

[0112] In an exemplary embodiment, the optical system 10 may satisfy: 0.55≤|FG12 / EFL|≤0.67, where FG12 is the combined focal length of the first element group G1 and the second element group G2, and EFL is the effective focal length of the optical system 10. Reasonable configuration of the ratio of the combined focal length of the first element group G1 and the second element group G2 to the effective focal length of the optical system 10 enables the optical system 10 to image objects that are relatively close to the optical system 10, ensuring that the optical system 10 has a larger imageable object distance range; at the same time, it can also enable the first element group G1 to have a certain convergence ability for light, which is conducive to reducing the shoulder height of the second element group G2, and ensure that the light enters the second element group G2 in a direction with a smaller angle with the optical axis II after passing through the first element group G1, thereby improving the optical anti-shake performance of the optical system 10.

[0113] In an exemplary embodiment, the optical system 10 may satisfy: 0.9 < |FG12 / FG3| < 1.1, where FG12 is the combined focal length of the first element group G1 and the second element group G2, and FG3 is the effective focal length of the third element group G3. By controlling the ratio of the combined focal length of the first element group G1 and the second element group G2 to the effective focal length of the third element group G3, the optical powers of the fixed element group (e.g., the first element group G1 and the second element group G2) and the moving element group (e.g., the third element group G3) can be reasonably allocated, improving the imaging performance of the optical system 10 for objects relatively close to the optical system 10 and expanding the range of object distances that can be imaged by the optical system 10.

[0114] In an exemplary embodiment, the optical system 10 may satisfy: 15.5 mm < |EFL / (FG12 / FG3)| < 35.0 mm, where FG12 is the combined focal length of the first element group G1 and the second element group G2, FG3 is the effective focal length of the third element group G3, and EFL is the effective focal length of the optical system 10. By controlling the above conditional expression, the optical powers of the fixed element group (e.g., the first element group G1 and the second element group G2) and the moving element group (e.g., the third element group G3) can be reasonably allocated, ensuring that the optical system 10 can achieve optimal focusing through limited movement of the moving element group when photographing objects in different object distance states, and the imaging performance of the optical system 10 is good in different object distance states, expanding the range of object distances that can be imaged by the optical system 10.

[0115] In an exemplary embodiment, the optical system 10 may satisfy: 4.2 < D1 / CT1 < 6.6, where D1 is the maximum effective semi-aperture of the first lens E1, and CT1 is the central thickness of the first lens E1 on the optical axis (such as the optical axis I). D1 may be, for example, the maximum of the effective semi-aperture of the object side of the first lens E1 and the effective semi-aperture of the image side of the first lens E1. By reasonably configuring the ratio of the maximum effective semi-aperture of the first lens E1 to the central thickness of the first lens E1, when the processability of the first lens E1 meets the requirements, the total height of the optical system 10 can be reduced, and the structure of the optical system 10 can be made more compact, thereby reducing the volume of the optical system 10; at the same time, it is also beneficial to achieve a large aperture of the optical system 10.

[0116] In an exemplary embodiment, the optical system 10 may satisfy: 2.2 < D2 / CT2 < 6.8, where D2 is the maximum effective semi-aperture of the second lens E2, and CT2 is the central thickness of the second lens E2 on the optical axis (such as the optical axis II). D2 may be, for example, the maximum value of the effective semi-aperture of the object side of the second lens E2 and the effective semi-aperture of the image side of the second lens E2. By reasonably configuring the ratio of the maximum effective semi-aperture of the second lens E2 to the central thickness of the second lens E2, when the processability of the second lens E2 meets the requirements, the total length of the optical system 10 can be reduced, and the structure of the optical system 10 can be made more compact, thereby reducing the volume of the optical system 10; at the same time, it is also beneficial to improve the optical image stabilization performance of the optical system 10.

[0117] In an exemplary embodiment, at least one of the first lens E1 to the eighth lens E8 may be a trimmed lens. The effective semi-apertures of the trimmed lens in the first direction and the second direction may be different. The first direction may be, for example, a direction perpendicular to the plane formed by the optical axis I and the optical axis II. The second direction may be, for example, a direction parallel to the optical axis I. By providing the trimmed lens, the total width of the rear-end element group (for example, the second element group G2 and the third element group G3) in the first direction or the shoulder height of the rear-end element group can be further reduced, thereby reducing the total width of the optical system 10 in the first direction or the total height of the optical system 10.

[0118] In an exemplary embodiment, the optical system 10 may satisfy: 0.02 mm -1 ≤ D2x / EPDx / d12 ≤ 0.10 mm -1 where D2x is the maximum effective semi-aperture of the second lens E2 in the first direction, EPDx is the entrance pupil diameter of the optical system 10 in the first direction, and d12 is the on-axis distance from the image side of the first lens E1 to the object side of the second lens E2. D2x may be, for example, the maximum value of the effective semi-aperture of the object side of the second lens E2 and the effective semi-aperture of the image side of the second lens E2 in the first direction. The first direction may be, for example, a direction perpendicular to the plane formed by the optical axis I and the optical axis II. By controlling the above conditional expression, while the optical system 10 meets the large aperture requirement, the effective aperture of the second lens E2 can be restricted within a reasonable range, which is beneficial to reducing the total width of the rear-end element group (for example, the second element group G2 and the third element group G3) in the first direction, thereby reducing the total width of the optical system 10 in the first direction.

[0119] In an exemplary embodiment, the optical system 10 may satisfy: 0.02 mm -1 ≤ D2y / EPDy / d12 ≤ 0.10 mm -1, where D2y is the maximum effective semi-aperture of the second lens E2 in the second direction, EPDy is the entrance pupil diameter of the optical system 10 in the second direction, and d12 is the on-axis distance from the image side of the first lens E1 to the object side of the second lens E2. D2y can be, for example, the maximum value among the effective semi-apertures of the object side and the image side of the second lens E2 in the second direction. The second direction can be, for example, a direction parallel to the optical axis I. By controlling the above conditional formula, while the optical system 10 meets the large aperture requirement, the effective aperture of the second lens E2 can be restricted within a reasonable range, which is beneficial to reducing the shoulder height of the rear element group (for example, the second element group G2 and the third element group G3), thereby reducing the total height of the optical system 10.

[0120] In an exemplary embodiment, the optical system 10 can satisfy: -0.60 < fs1 / fs2 < 1.85, where fs1 is the effective focal length of the object side of the first lens E1 and fs2 is the effective focal length of the image side of the first lens E1. Reasonably configuring the ratio of the effective focal lengths of the object side and the image side of the first lens E1 can enable the first lens E1 to have sufficient converging ability and limit the surface shape trends of the object side and the image side of the first lens E1, thereby reducing the shoulder height of the rear element group (for example, the second element group G2 and the third element group G3) and reducing the total height of the optical system 10.

[0121] In an exemplary embodiment, referring to Figure 1A , the optical system 10 can satisfy: 0.6 < EFL / SL < 0.8, where EFL is the effective focal length of the optical system 10 and SL is the total length of the optical system 10 along the direction of the second optical axis. Reasonably configuring the ratio of the effective focal length of the optical system 10 to the total length of the optical system 10 along the direction of the second optical axis is beneficial to shortening the total length of the optical system 10 and thus reducing the volume of the optical system 10 when the optical system 10 realizes characteristics such as long focal length, large aperture, and a certain image plane size.

[0122] In an exemplary embodiment, the optical system 10 can satisfy: 0.95 ≤ SD1 / SD2 ≤ 1.12, where SD1 is the maximum effective semi-aperture of the lens closest to the object side in the second element group G2, and SD2 is the maximum effective semi-aperture of another lens adjacent to the lens closest to the object side in the second element group G2. SD1 can be, for example, the maximum effective semi-aperture of the third lens E3, and SD2 can be, for example, the maximum effective semi-aperture of the fourth lens E4. The maximum effective semi-aperture of a lens can be, for example, the maximum value among the effective semi-apertures of the object side and the image side of the lens. Reasonably configuring the ratio of the maximum effective semi-apertures of the third lens E3 and the fourth lens E4 in the second element group G2 is beneficial to reducing the total height of the optical system 10 while ensuring the performance of the optical system 10.

[0123] In an exemplary embodiment, the optical system 10 may satisfy: 0.1 < tan(FOV / 2) < 0.4, where FOV is the maximum field of view angle of the optical system 10. By reasonably configuring the tangent value of half of the maximum field of view angle of the optical system 10, the optical system 10 can have a relatively small field of view angle, which is beneficial for the optical system 10 to image distant objects, thereby ensuring good imaging quality of the optical system 10 at a long distance.

[0124] In an exemplary embodiment, the optical system 10 may satisfy: OBJmin ≥ 10 cm, where OBJmin is the minimum value of the object distance of the optical system 10. The object distance may be, for example, the distance between the object to be photographed and the optical system 10. As an example, 10 cm ≤ OBJmin < 20 cm. By controlling the above conditional expression, the optical system 10 can image under the condition that the object distance is greater than or equal to 10 cm, and the imaging effect is good.

[0125] In an exemplary embodiment, the magnification of the optical system 10 may be greater than or equal to 2.5X and less than or equal to 10X.

[0126] The optical system 10 according to the above embodiment of the present application may employ eight lenses and one reflective element. By reasonably allocating the optical parameters of each lens and the reflective element, when the size of the optical system 10 meets the requirements, it is beneficial for the optical system 10 to achieve characteristics such as long focal length and large aperture, improve the imaging quality and optical image stabilization performance of the optical system 10, and reduce the weight of the optical system 10.

[0127] In the present application, SL represents the total length of the optical system 10 along the direction of the second optical axis, specifically, SL is the distance between the first lens E1 and the image plane IMA along the optical axis II. GH represents the shoulder height of the rear element group (for example, the second element group G2 and the third element group G3), specifically, GH is determined by the maximum effective aperture of the lens in the second element group G2 and the third element group G3 in the second direction (for example, the direction parallel to the optical axis I). SH represents the total height of the optical system 10, specifically, SH is the total height of the optical system 10 in the second direction (for example, the direction parallel to the optical axis I). d12 represents the axial distance from the image side surface of the first lens E1 to the object side surface of the second lens E2, specifically, d12 is the sum of the distance between the image side surface of the first lens E1 and the reflective element P along the optical axis I and the distance between the reflective element P and the object side surface of the second lens E2 along the optical axis II. Modulation transfer function (MTF) is an important indicator to describe the imaging quality of the optical system 10, and MTF can be obtained through simulation. The Optical Image Stabilizer (OIS) sensitivity is the MTF drop value, which represents the difference between the MTF at a unit jitter angle and the static MTF design value.

[0128] Those skilled in the art should understand that, without departing from the technical solution claimed in the present application, the number of lenses constituting the optical system 10 can be changed to obtain the various results and advantages described in this specification.

[0129] Specific embodiments of the optical system applicable to the above-mentioned embodiments will be further described below with reference to the accompanying drawings. Example 1

[0130] The following reference Figure 2 , Figure 3 , Figure 4A , Figure 4B and Figure 4C The optical system of Embodiment 1 is described.

[0131] like Figure 2 and Figure 3 As shown, the optical system 100 may include a first element group G1, a second element group G2, and a third element group G3 arranged in sequence from the object side to the image side. The image side may be provided with an image plane IMA, for example. The imageable object distance range of the optical system 100 may be 17 cm to infinity. The magnification of the optical system 100 may be 2.5X.

[0132] The first element group G1 may include a first lens E1, a reflective element P, and a second lens E2. The second element group G2 may include an aperture STO, a third lens E3, a fourth lens E4, and a fifth lens E5. The third element group G3 may include a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 is located on the optical axis I and is arranged between the object side and the reflective element P. The second lens E2, the aperture STO, the third lens E3, the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7, and the eighth lens E8 are arranged in sequence from the reflective element P to the image side along the optical axis II. In one example, a filter E9 may be provided between the eighth lens E8 and the image plane IMA.

[0133] The first element group G1 and the second element group G2 are fixed in position relative to the image plane IMA on the optical axis II. The third element group G3 can move relative to the second element group G2 along the optical axis II. When the distance between the object and the optical system 100 changes from far to near, the distance between the third element group G3 and the second element group G2 on the optical axis II is adjusted, so that the optical system 100 can switch between the first state and the second state, thereby realizing the focusing function of the optical system 100. During the focusing process of the optical system 100, the maximum movement stroke of the third element group G3 can be 1.0898 mm.

[0134] The first lens E1 may have positive power, and its object side surface S1 is convex, and its image side surface S2 is concave. The reflective element P may have a reflective surface S3, and the reflective surface S3 is a plane. The second lens E2 may have negative power, and its object side surface S4 is convex, and its image side surface S5 is concave. The third lens E3 may have positive power, and its object side surface S6 is convex, and its image side surface S7 is convex. The fourth lens E4 may have negative power, and its object side surface S8 is convex, and its image side surface S9 is concave. The fifth lens E5 may have positive power, and its object side surface S10 is concave, and its image side surface S11 is convex. The sixth lens E6 may have positive power, and its object side surface S12 is concave, and its image side surface S13 is convex. The seventh lens E7 may have positive power, and its object side surface S14 is concave, and its image side surface S15 is convex. The eighth lens E8 may have negative power, and its object-side surface S16 is convex, and its image-side surface S17 is concave. The filter E9 may have an object-side surface S18 and an image-side surface S19. Light from the object passes through each surface S1 to S19 in sequence and is finally imaged on the image plane IMA.

[0135] Table 1 shows a basic parameter table of the optical system 100 of Example 1, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm).

[0136] Table 1

[0137]

[0138] In this embodiment, the positive and negative values ​​of the numerical signs of the radius of curvature of each surface only indicate the curvature direction of the surface. When the curvature directions of the surfaces of the lenses on the optical axis I and the optical axis II are the same, the positive and negative values ​​of the numerical signs of the radius of curvature of the surfaces are opposite. Similarly, the positive and negative values ​​of the numerical signs of the thickness / distance of each surface only indicate the direction. The curvature direction of each surface and the thickness / distance of each surface can be referred to Figure 2 and Figure 3 .

[0139] The on-axis distance W1 from the second element group G2 to the third element group G3 and the on-axis distance W2 from the third element group G3 to the filter E9 are variables, which may change as the distance between the object and the optical system 100 changes.

[0140] When the object is infinitely far from the optical system 100, the optical system 100 is in the first state. The structure diagram of the optical system 100 can be referred to Figure 2 , where W1=-1.0163mm, W2=-4.5910mm, effective focal length EFL of optical system 100=15.20mm, maximum field of view FOV of optical system 100=41.72°, aperture value Fnox of optical system 100 in the first direction=2.34, aperture value Fnoy of optical system 100 in the second direction=3.35. When the object is at a predetermined distance from optical system 100, optical system 100 is in the second state, and the structure diagram of optical system 100 can be referred to Figure 3 .

[0141] In this embodiment, the object side surface and the image side surface of any lens among the first lens E1 to the eighth lens E8 are both aspherical surfaces, and the surface shape of each aspherical lens can be defined by but not limited to the following aspherical surface formula:

[0142] (1)

[0143] Where X(Y) represents the relative distance between the point on the aspherical surface that is Y away from the optical axis and the tangent plane that is tangent to the optical axis of the aspherical surface; Y represents the vertical distance between the point on the aspherical curve and the optical axis; R represents the radius of curvature; K represents the cone coefficient; A m represents the i-th order Qcon aspheric coefficient; u=(Y / NR), where NR represents the normalized radius of the Qcon aspheric surface; Table 2 shows the cone coefficient K and the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, 10 , A 12 , A 14 , A 16 , A 18and A 20 .

[0144] Table 2

[0145]

[0146] Figure 4A The axial chromatic aberration curve of the first state of the optical system 100 of Example 1 is shown, which indicates the deviation of the convergence point of light rays of different wavelengths after passing through the optical system 100 . Figure 4B The astigmatism curve of the first state of the optical system 100 of Example 1 is shown, which represents the meridional image curvature and the sagittal image curvature corresponding to different image heights. Figure 4C The distortion curve of the first state of the optical system 100 of Example 1 is shown, which indicates the distortion magnitude values ​​corresponding to different image heights. Figure 4A , Figure 4B and Figure 4C It can be seen that the optical system 100 of Example 1 can achieve good imaging quality in the first state. Example 2

[0147] The following reference Figure 5 , Figure 6 , Fig. 7A , Figure 7B and Figure 7C The optical system of Embodiment 2 is described.

[0148] like Figure 5 and Figure 6 As shown, the optical system 200 may include a first element group G1, a second element group G2, and a third element group G3 arranged in sequence from the object side to the image side. The image side may be provided with an image plane IMA, for example. The imageable object distance range of the optical system 200 may be 10 cm to infinity. The magnification of the optical system 200 may be 5X.

[0149] The first element group G1 may include a first lens E1, a reflective element P, and a second lens E2. The second element group G2 may include an aperture STO, a third lens E3, a fourth lens E4, and a fifth lens E5. The third element group G3 may include a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 is located on the optical axis I and is arranged between the object side and the reflective element P. The second lens E2, the aperture STO, the third lens E3, the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7, and the eighth lens E8 are arranged in sequence from the reflective element P to the image side along the optical axis II. In one example, a filter E9 may be provided between the eighth lens E8 and the image plane IMA.

[0150] The first element group G1 and the second element group G2 are fixed in position relative to the image plane IMA on the optical axis II. The third element group G3 can move relative to the second element group G2 along the optical axis II. When the distance between the object and the optical system 200 changes from far to near, the distance between the third element group G3 and the second element group G2 on the optical axis II is adjusted, so that the optical system 200 can switch between the first state and the second state, thereby realizing the focusing function of the optical system 200. During the focusing process of the optical system 200, the maximum movement stroke of the third element group G3 can be 6.4288 mm.

[0151] The first lens E1 may have positive power, and its object side surface S1 is convex, and its image side surface S2 is convex. The reflective element P may have a reflective surface S3, and the reflective surface S3 is a plane. The second lens E2 may have negative power, and its object side surface S4 is concave, and its image side surface S5 is concave. The third lens E3 may have positive power, and its object side surface S6 is convex, and its image side surface S7 is convex. The fourth lens E4 may have negative power, and its object side surface S8 is convex, and its image side surface S9 is concave. The fifth lens E5 may have positive power, and its object side surface S10 is convex, and its image side surface S11 is convex. The sixth lens E6 may have negative power, and its object side surface S12 is concave, and its image side surface S13 is convex. The seventh lens E7 may have positive power, and its object side surface S14 is convex, and its image side surface S15 is convex. The eighth lens E8 may have negative power, and its object-side surface S16 is convex, and its image-side surface S17 is concave. The filter E9 may have an object-side surface S18 and an image-side surface S19. Light from the object passes through each surface S1 to S19 in sequence and is finally imaged on the image plane IMA.

[0152] Table 3 shows a basic parameter table of the optical system 200 of Example 2, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm).

[0153] Table 3

[0154]

[0155] In this embodiment, the positive and negative values ​​of the numerical signs of the radius of curvature of each surface only indicate the curvature direction of the surface. When the curvature directions of the surfaces of the lenses on the optical axis I and the optical axis II are the same, the positive and negative values ​​of the numerical signs of the radius of curvature of the surfaces are opposite. Similarly, the positive and negative values ​​of the numerical signs of the thickness / distance of each surface only indicate the direction. The curvature direction of each surface and the thickness / distance of each surface can be referred to Figure 5 and Figure 6 .

[0156] The on-axis distance W1 from the second element group G2 to the third element group G3 and the on-axis distance W2 from the third element group G3 to the filter E9 are variables, which may change as the distance between the object and the optical system 200 changes.

[0157] When the object is infinitely far from the optical system 200, the optical system 200 is in the first state. The structure diagram of the optical system 200 can be referred to Figure 5 , where W1=-1.0671mm, W2=-9.8559mm, effective focal length EFL of optical system 200=31.70mm, maximum field of view FOV of optical system 200=20.3122°, aperture value Fnox of optical system 200 in the first direction=1.71, aperture value Fnoy of optical system 200 in the second direction=2.44. When the object is at a predetermined distance from the optical system 200, the optical system 200 is in the second state. The structure diagram of the optical system 200 can be referred to Figure 6 .

[0158] In this embodiment, the object side surface and the image side surface of any lens from the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 4 shows the cone coefficient K and the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A59, A60, A61, A71, A72, A73, A74, A75 10 , A 12 , A 14 , A 16 , A 18 and A 20 .

[0159] Table 4

[0160]

[0161] Fig. 7A The axial chromatic aberration curve of the first state of the optical system 200 of Example 2 is shown, which indicates the deviation of the convergence point of light rays of different wavelengths after passing through the optical system 200. Figure 7B The astigmatism curve of the first state of the optical system 200 of Example 2 is shown, which represents the meridional image plane curvature and the sagittal image plane curvature corresponding to different image heights. Figure 7C The distortion curve of the first state of the optical system 200 of Example 2 is shown, which indicates the distortion magnitude values ​​corresponding to different image heights. Fig. 7A , Figure 7B and Figure 7C It can be seen that the optical system 200 of Example 2 can achieve good imaging quality in the first state. Example 3

[0162] The following reference Figure 8 , Fig. 9 , Fig. 10A , Fig. 10B and Fig. 10C The optical system of Embodiment 3 is described.

[0163] like Figure 8 and Fig. 9 As shown, the optical system 300 may include a first element group G1, a second element group G2, and a third element group G3 arranged in sequence from the object side to the image side. The image side may be provided with an image plane IMA, for example. The imageable object distance range of the optical system 300 may be 10 cm to infinity. The magnification of the optical system 300 may be 5X.

[0164] The first element group G1 may include a first lens E1, a reflective element P, and a second lens E2. The second element group G2 may include an aperture STO, a third lens E3, a fourth lens E4, and a fifth lens E5. The third element group G3 may include a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 is located on the optical axis I and is arranged between the object side and the reflective element P. The second lens E2, the aperture STO, the third lens E3, the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7, and the eighth lens E8 are arranged in sequence from the reflective element P to the image side along the optical axis II. In one example, a filter E9 may be provided between the eighth lens E8 and the image plane IMA.

[0165] The first element group G1 and the second element group G2 are fixed in position relative to the image plane IMA on the optical axis II. The third element group G3 can move relative to the second element group G2 along the optical axis II. When the distance between the object and the optical system 300 changes from far to near, the distance between the third element group G3 and the second element group G2 on the optical axis II is adjusted, so that the optical system 300 can switch between the first state and the second state, thereby realizing the focusing function of the optical system 300. During the focusing process of the optical system 300, the maximum movement stroke of the third element group G3 can be 6.3414 mm.

[0166] The first lens E1 may have positive power, and its object side surface S1 is convex, and its image side surface S2 is convex. The reflective element P may have a reflective surface S3, and the reflective surface S3 is a plane. The second lens E2 may have negative power, and its object side surface S4 is concave, and its image side surface S5 is concave. The third lens E3 may have positive power, and its object side surface S6 is convex, and its image side surface S7 is convex. The fourth lens E4 may have negative power, and its object side surface S8 is convex, and its image side surface S9 is concave. The fifth lens E5 may have positive power, and its object side surface S10 is convex, and its image side surface S11 is convex. The sixth lens E6 may have negative power, and its object side surface S12 is concave, and its image side surface S13 is convex. The seventh lens E7 may have positive power, and its object side surface S14 is convex, and its image side surface S15 is convex. The eighth lens E8 may have negative power, and its object-side surface S16 is convex, and its image-side surface S17 is concave. The filter E9 may have an object-side surface S18 and an image-side surface S19. Light from the object passes through each surface S1 to S19 in sequence and is finally imaged on the image plane IMA.

[0167] Table 5 shows a basic parameter table of the optical system 300 of Example 3, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm).

[0168] Table 5

[0169]

[0170] In this embodiment, the positive and negative values ​​of the numerical signs of the radius of curvature of each surface only indicate the curvature direction of the surface. When the curvature directions of the surfaces of the lenses on the optical axis I and the optical axis II are the same, the positive and negative values ​​of the numerical signs of the radius of curvature of the surfaces are opposite. Similarly, the positive and negative values ​​of the numerical signs of the thickness / distance of each surface only indicate the direction. The curvature direction of each surface and the thickness / distance of each surface can be referred to Figure 8 and Fig. 9 .

[0171] The on-axis distance W1 from the second element group G2 to the third element group G3 and the on-axis distance W2 from the third element group G3 to the filter E9 are variables, which may change as the distance between the object and the optical system 300 changes.

[0172] When the object is infinitely far from the optical system 300, the optical system 300 is in the first state. The structure diagram of the optical system 300 can be referred to Figure 8, where W1=-1.1220mm, W2=-10.7125mm, effective focal length EFL of optical system 300=31.70mm, maximum field of view FOV of optical system 300=20.3122°, aperture value Fnox of optical system 300 in the first direction=2.34, aperture value Fnoy of optical system 300 in the second direction=3.35. When the object is at a predetermined distance from the optical system 300, the optical system 300 is in the second state. The structure diagram of the optical system 300 can be referred to Fig. 9 .

[0173] In this embodiment, the object side surface and the image side surface of any lens from the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 6 shows the cone coefficient K and the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A59, A60, A61, A71, A72, A73, A74, A75 10 , A 12 , A 14 , A 16 , A 18 and A 20 .

[0174] Table 6

[0175]

[0176] Fig. 10A The axial chromatic aberration curve of the first state of the optical system 300 of Example 3 is shown, which indicates that the convergence point of light rays of different wavelengths after passing through the optical system 300 deviates. Fig. 10B The astigmatism curve of the first state of the optical system 300 of Example 3 is shown, which represents the meridional image plane curvature and the sagittal image plane curvature corresponding to different image heights. Fig. 10C The distortion curve of the first state of the optical system 300 of Example 3 is shown, which indicates the distortion magnitude values ​​corresponding to different image heights. Fig. 10A , Fig. 10B and Fig. 10C It can be seen that the optical system 300 of Example 3 can achieve good imaging quality in the first state. Example 4

[0177] The following reference Fig.11 , Fig.12 , Fig.13A , Fig. 13B and Fig. 13C The optical system of Embodiment 4 is described.

[0178] like Fig.11 and Fig.12As shown, the optical system 400 may include a first element group G1, a second element group G2, and a third element group G3 arranged in sequence from the object side to the image side. The image side may be provided with an image plane IMA, for example. The imageable object distance range of the optical system 400 may be 10 cm to infinity. The magnification of the optical system 400 may be 8X.

[0179] The first element group G1 may include a first lens E1, a reflective element P, and a second lens E2. The second element group G2 may include an aperture STO, a third lens E3, a fourth lens E4, and a fifth lens E5. The third element group G3 may include a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 is located on the optical axis I and is arranged between the object side and the reflective element P. The second lens E2, the aperture STO, the third lens E3, the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7, and the eighth lens E8 are arranged in sequence from the reflective element P to the image side along the optical axis II. In one example, a filter E9 may be provided between the eighth lens E8 and the image plane IMA.

[0180] The first element group G1 and the second element group G2 are fixed in position relative to the image plane IMA on the optical axis II. The third element group G3 can move relative to the second element group G2 along the optical axis II. When the distance between the object and the optical system 400 changes from far to near, the distance between the third element group G3 and the second element group G2 on the optical axis II is adjusted, so that the optical system 400 can switch between the first state and the second state, thereby realizing the focusing function of the optical system 400. During the focusing process of the optical system 400, the maximum movement stroke of the third element group G3 can be 4.1221 mm.

[0181] The first lens E1 may have positive power, and its object side surface S1 is convex, and its image side surface S2 is convex. The reflective element P may have a reflective surface S3, and the reflective surface S3 is a plane. The second lens E2 may have negative power, and its object side surface S4 is concave, and its image side surface S5 is concave. The third lens E3 may have positive power, and its object side surface S6 is convex, and its image side surface S7 is convex. The fourth lens E4 may have negative power, and its object side surface S8 is convex, and its image side surface S9 is concave. The fifth lens E5 may have positive power, and its object side surface S10 is convex, and its image side surface S11 is convex. The sixth lens E6 may have negative power, and its object side surface S12 is concave, and its image side surface S13 is convex. The seventh lens E7 may have positive power, and its object side surface S14 is concave, and its image side surface S15 is convex. The eighth lens E8 may have negative power, and its object-side surface S16 is concave, and its image-side surface S17 is concave. The filter E9 may have an object-side surface S18 and an image-side surface S19. Light from the object passes through each surface S1 to S19 in sequence and is finally imaged on the image plane IMA.

[0182] Table 7 shows a basic parameter table of the optical system 400 of Example 4, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm).

[0183] Table 7

[0184]

[0185] In this embodiment, the positive and negative values ​​of the numerical signs of the radius of curvature of each surface only indicate the curvature direction of the surface. When the curvature directions of the surfaces of the lenses on the optical axis I and the optical axis II are the same, the positive and negative values ​​of the numerical signs of the radius of curvature of the surfaces are opposite. Similarly, the positive and negative values ​​of the numerical signs of the thickness / distance of each surface only indicate the direction. The curvature direction of each surface and the thickness / distance of each surface can be referred to Fig.11 and Fig.12 .

[0186] The on-axis distance W1 from the second element group G2 to the third element group G3 and the on-axis distance W2 from the third element group G3 to the filter E9 are variables, which may change as the distance between the object and the optical system 400 changes.

[0187] When the object is infinitely far from the optical system 400, the optical system 400 is in the first state. The structure diagram of the optical system 400 can be referred to Fig.11 , where W1=-1.3278mm, W2=-7.4926mm, effective focal length EFL of optical system 400=27.73mm, maximum field of view FOV of optical system 400=12.3122°, aperture value Fnox of optical system 400 in the first direction=2.34, aperture value Fnoy of optical system 400 in the second direction=3.35. When the object is at a predetermined distance from optical system 400, optical system 400 is in the second state. The structure diagram of optical system 400 can be referred to Fig.12 .

[0188] In this embodiment, the object side surface and the image side surface of any lens from the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 8 shows the cone coefficient K and the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A59, A60, A61, A71, A72, A73, A74, A75 10 , A 12 , A 14 , A 16 , A 18 and A 20 .

[0189] Table 8

[0190]

[0191] Fig.13AThe axial chromatic aberration curve of the first state of the optical system 400 of Example 4 is shown, which indicates the deviation of the convergence point of light rays of different wavelengths after passing through the optical system 400. Fig. 13B The astigmatism curve of the first state of the optical system 400 of Example 4 is shown, which represents the meridional image plane curvature and the sagittal image plane curvature corresponding to different image heights. Fig. 13C The distortion curve of the first state of the optical system 400 of Example 4 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Fig.13A , Fig. 13B and Fig. 13C It can be seen that the optical system 400 of Example 4 can achieve good imaging quality in the first state. Example 5

[0192] The following reference Fig.14 , Fig.15 , Fig.16A , Fig. 16B and Fig. 16C The optical system of Embodiment 5 is described.

[0193] like Fig.14 and Fig.15 As shown, the optical system 500 may include a first element group G1, a second element group G2, and a third element group G3 arranged in sequence from the object side to the image side. The image side may be provided with an image plane IMA, for example. The imageable object distance range of the optical system 500 may be 17 cm to infinity. The magnification of the optical system 500 may be 2.5X.

[0194] The first element group G1 may include a first lens E1, a reflective element P, and a second lens E2. The second element group G2 may include an aperture STO, a third lens E3, a fourth lens E4, and a fifth lens E5. The third element group G3 may include a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 is located on the optical axis I and is arranged between the object side and the reflective element P. The second lens E2, the aperture STO, the third lens E3, the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7, and the eighth lens E8 are arranged in sequence from the reflective element P to the image side along the optical axis II. In one example, a filter E9 may be provided between the eighth lens E8 and the image plane IMA.

[0195] The first element group G1 and the second element group G2 are fixed in position relative to the image plane IMA on the optical axis II. The third element group G3 can move relative to the second element group G2 along the optical axis II. When the distance between the object and the optical system 500 changes from far to near, the distance between the third element group G3 and the second element group G2 on the optical axis II is adjusted, so that the optical system 500 can switch between the first state and the second state, thereby realizing the focusing function of the optical system 500. During the focusing process of the optical system 500, the maximum movement stroke of the third element group G3 can be 1.0087 mm.

[0196] The first lens E1 may have positive power, and its object side surface S1 is convex, and its image side surface S2 is concave. The reflective element P may have a reflective surface S3, and the reflective surface S3 is a plane. The second lens E2 may have negative power, and its object side surface S4 is convex, and its image side surface S5 is concave. The third lens E3 may have positive power, and its object side surface S6 is convex, and its image side surface S7 is convex. The fourth lens E4 may have negative power, and its object side surface S8 is convex, and its image side surface S9 is concave. The fifth lens E5 may have positive power, and its object side surface S10 is convex, and its image side surface S11 is convex. The sixth lens E6 may have positive power, and its object side surface S12 is concave, and its image side surface S13 is convex. The seventh lens E7 may have positive power, and its object side surface S14 is concave, and its image side surface S15 is convex. The eighth lens E8 may have negative power, and its object-side surface S16 is convex, and its image-side surface S17 is concave. The filter E9 may have an object-side surface S18 and an image-side surface S19. Light from the object passes through each surface S1 to S19 in sequence and is finally imaged on the image plane IMA.

[0197] Table 9 shows a basic parameter table of the optical system 500 of Example 5, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm).

[0198] Table 9

[0199]

[0200] In this embodiment, the positive and negative values ​​of the numerical signs of the radius of curvature of each surface only indicate the curvature direction of the surface. When the curvature directions of the surfaces of the lenses on the optical axis I and the optical axis II are the same, the positive and negative values ​​of the numerical signs of the radius of curvature of the surfaces are opposite. Similarly, the positive and negative values ​​of the numerical signs of the thickness / distance of each surface only indicate the direction. The curvature direction of each surface and the thickness / distance of each surface can be referred to Fig.14 and Fig.15 .

[0201] The on-axis distance W1 from the second element group G2 to the third element group G3 and the on-axis distance W2 from the third element group G3 to the filter E9 are variables, which may change as the distance between the object and the optical system 500 changes.

[0202] When the object is infinitely far from the optical system 500, the optical system 500 is in the first state. The structure diagram of the optical system 500 can be referred to Fig.14 , where W1=-1.0343mm, W2=-4.5275mm, effective focal length EFL of optical system 500=15.19mm, maximum field of view FOV of optical system 500=41.72°, aperture value Fnox of optical system 500 in the first direction=3.3, aperture value Fnoy of optical system 500 in the second direction=3.3. When the object is at a predetermined distance from the optical system 500, the optical system 500 is in the second state. The structural diagram of the optical system 500 can be referred to Fig.15 .

[0203] In this embodiment, the object side surface and the image side surface of any lens from the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 10 shows the cone coefficient K and the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A59, A60, A61, A71, A72, A73, A74, A75 10 , A 12 , A 14 , A 16 , A 18 and A 20 .

[0204] Table 10

[0205]

[0206] Fig.16A The axial chromatic aberration curve of the first state of the optical system 500 of Example 5 is shown, which indicates the deviation of the convergence point of light rays of different wavelengths after passing through the optical system 500. Fig. 16B The astigmatism curve of the first state of the optical system 500 of Example 5 is shown, which represents the meridional image plane curvature and the sagittal image plane curvature corresponding to different image heights. Fig. 16C The distortion curve of the first state of the optical system 500 of Example 5 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Fig.16A , Fig. 16B and Fig. 16C It can be seen that the optical system 500 of Example 5 can achieve good imaging quality in the first state. Example 6

[0207] The following reference Fig.17 , Fig.18 , Fig.19A , Fig.19B and Fig.19C The optical system of Embodiment 6 is described.

[0208] like Fig.17 and Fig.18 As shown, the optical system 600 may include a first element group G1, a second element group G2, and a third element group G3 arranged in sequence from the object side to the image side. The image side may be provided with an image plane IMA, for example. The imageable object distance range of the optical system 600 may be 10 cm to infinity. The magnification of the optical system 600 may be 5X.

[0209] The first element group G1 may include a first lens E1, a reflective element P, and a second lens E2. The second element group G2 may include an aperture STO, a third lens E3, a fourth lens E4, and a fifth lens E5. The third element group G3 may include a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 is located on the optical axis I and is arranged between the object side and the reflective element P. The second lens E2, the aperture STO, the third lens E3, the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7, and the eighth lens E8 are arranged in sequence from the reflective element P to the image side along the optical axis II. In one example, a filter E9 may be provided between the eighth lens E8 and the image plane IMA.

[0210] The first element group G1 and the second element group G2 are fixed in position relative to the image plane IMA on the optical axis II. The third element group G3 can move relative to the second element group G2 along the optical axis II. When the distance between the object and the optical system 600 changes from far to near, the distance between the third element group G3 and the second element group G2 on the optical axis II is adjusted, so that the optical system 600 can switch between the first state and the second state, thereby realizing the focusing function of the optical system 600. During the focusing process of the optical system 600, the maximum movement stroke of the third element group G3 can be 5.8859 mm.

[0211] The first lens E1 may have positive power, and its object side surface S1 is convex, and its image side surface S2 is convex. The reflective element P may have a reflective surface S3, and the reflective surface S3 is a plane. The second lens E2 may have negative power, and its object side surface S4 is concave, and its image side surface S5 is concave. The third lens E3 may have positive power, and its object side surface S6 is convex, and its image side surface S7 is convex. The fourth lens E4 may have negative power, and its object side surface S8 is convex, and its image side surface S9 is concave. The fifth lens E5 may have positive power, and its object side surface S10 is convex, and its image side surface S11 is convex. The sixth lens E6 may have negative power, and its object side surface S12 is concave, and its image side surface S13 is convex. The seventh lens E7 may have positive power, and its object side surface S14 is concave, and its image side surface S15 is convex. The eighth lens E8 may have negative power, and its object-side surface S16 is convex, and its image-side surface S17 is concave. The filter E9 may have an object-side surface S18 and an image-side surface S19. Light from the object passes through each surface S1 to S19 in sequence and is finally imaged on the image plane IMA.

[0212] Table 11 shows a basic parameter table of the optical system 600 of Example 6, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm).

[0213] Table 11

[0214]

[0215] In this embodiment, the positive and negative values ​​of the numerical signs of the radius of curvature of each surface only indicate the curvature direction of the surface. When the curvature directions of the surfaces of the lenses on the optical axis I and the optical axis II are the same, the positive and negative values ​​of the numerical signs of the radius of curvature of the surfaces are opposite. Similarly, the positive and negative values ​​of the numerical signs of the thickness / distance of each surface only indicate the direction. The curvature direction of each surface and the thickness / distance of each surface can be referred to Fig.17 and Fig.18 .

[0216] The on-axis distance W1 from the second element group G2 to the third element group G3 and the on-axis distance W2 from the third element group G3 to the filter E9 are variables, which may change as the distance between the object and the optical system 600 changes.

[0217] When the object is infinitely far from the optical system 600, the optical system 600 is in the first state. The structure diagram of the optical system 600 can be referred to Fig.17, where W1=-1.1538mm, W2=-9.4875mm, effective focal length EFL of optical system 600=31.68mm, maximum field of view FOV of optical system 600=20.3122°, aperture value Fnox of optical system 600 in the first direction=1.9, aperture value Fnoy of optical system 600 in the second direction=1.9. When the object is at a predetermined distance from optical system 600, optical system 600 is in the second state. The structure diagram of optical system 600 can be referred to Fig.18 .

[0218] In this embodiment, the object side surface and the image side surface of any lens from the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 12 shows the cone coefficient K and the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A59, A60, A61, A71, A72, A73, A74, A75 10 , A 12 , A 14 , A 16 , A 18 and A 20 .

[0219] Table 12

[0220]

[0221] Fig.19A The axial chromatic aberration curve of the first state of the optical system 600 of Example 6 is shown, which indicates the deviation of the convergence point of light of different wavelengths after passing through the optical system 600. Fig.19B The astigmatism curve of the first state of the optical system 600 of Example 6 is shown, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Fig.19C The distortion curve of the first state of the optical system 600 of Example 6 is shown, which indicates the distortion magnitude values ​​corresponding to different image heights. Fig.19A , Fig.19B and Fig.19C It can be seen that the optical system 600 of Example 6 can achieve good imaging quality in the first state. Example 7

[0222] The following reference Fig. 20 , Fig.21 , Fig.22A , Fig. 22B and Fig. 22C The optical system of Example 7 is described.

[0223] like Fig. 20 and Fig.21As shown, the optical system 700 may include a first element group G1, a second element group G2, and a third element group G3 arranged in sequence from the object side to the image side. The image side may be provided with an image plane IMA, for example. The imageable object distance range of the optical system 700 may be 10 cm to infinity. The magnification of the optical system 700 may be 5X.

[0224] The first element group G1 may include a first lens E1, a reflective element P, and a second lens E2. The second element group G2 may include an aperture STO, a third lens E3, a fourth lens E4, and a fifth lens E5. The third element group G3 may include a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 is located on the optical axis I and is arranged between the object side and the reflective element P. The second lens E2, the aperture STO, the third lens E3, the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7, and the eighth lens E8 are arranged in sequence from the reflective element P to the image side along the optical axis II. In one example, a filter E9 may be provided between the eighth lens E8 and the image plane IMA.

[0225] The first element group G1 and the second element group G2 are fixed in position relative to the image plane IMA on the optical axis II. The third element group G3 can move relative to the second element group G2 along the optical axis II. When the distance between the object and the optical system 700 changes from far to near, the distance between the third element group G3 and the second element group G2 on the optical axis II is adjusted, so that the optical system 700 can switch between the first state and the second state, thereby realizing the focusing function of the optical system 700. During the focusing process of the optical system 700, the maximum moving stroke of the third element group G3 can be 5.6900 mm.

[0226] The first lens E1 may have positive power, and its object side surface S1 is convex, and its image side surface S2 is convex. The reflective element P may have a reflective surface S3, and the reflective surface S3 is a plane. The second lens E2 may have negative power, and its object side surface S4 is concave, and its image side surface S5 is concave. The third lens E3 may have positive power, and its object side surface S6 is convex, and its image side surface S7 is convex. The fourth lens E4 may have negative power, and its object side surface S8 is convex, and its image side surface S9 is concave. The fifth lens E5 may have positive power, and its object side surface S10 is convex, and its image side surface S11 is convex. The sixth lens E6 may have negative power, and its object side surface S12 is concave, and its image side surface S13 is convex. The seventh lens E7 may have positive power, and its object side surface S14 is concave, and its image side surface S15 is convex. The eighth lens E8 may have negative power, and its object-side surface S16 is convex, and its image-side surface S17 is concave. The filter E9 may have an object-side surface S18 and an image-side surface S19. Light from the object passes through each surface S1 to S19 in sequence and is finally imaged on the image plane IMA.

[0227] Table 13 shows a basic parameter table of the optical system 700 of Example 7, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm).

[0228] Table 13

[0229]

[0230] In this embodiment, the positive and negative values ​​of the numerical signs of the radius of curvature of each surface only indicate the curvature direction of the surface. When the curvature directions of the surfaces of the lenses on the optical axis I and the optical axis II are the same, the positive and negative values ​​of the numerical signs of the radius of curvature of the surfaces are opposite. Similarly, the positive and negative values ​​of the numerical signs of the thickness / distance of each surface only indicate the direction. The curvature direction of each surface and the thickness / distance of each surface can be referred to Fig. 20 and Fig.21 .

[0231] The on-axis distance W1 from the second element group G2 to the third element group G3 and the on-axis distance W2 from the third element group G3 to the filter E9 are variables, which may change as the distance between the object and the optical system 700 changes.

[0232] When the object is infinitely far from the optical system 700, the optical system 700 is in the first state. The structure diagram of the optical system 700 can be referred to Fig. 20 , where W1=-1.2426mm, W2=-10.5278mm, effective focal length EFL of optical system 700=31.70mm, maximum field of view FOV of optical system 700=20.3122°, aperture value Fnox of optical system 700 in the first direction=2.6, aperture value Fnoy of optical system 700 in the second direction=2.6. When the object is at a predetermined distance from optical system 700, optical system 700 is in the second state. The structure diagram of optical system 700 can be referred to Fig.21 .

[0233] In this embodiment, the object side surface and the image side surface of any lens from the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 14 shows the cone coefficient K and the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A59, A60, A61, A71, A72, A73, A74, A75 10 , A 12 , A 14 , A 16 , A 18 and A 20 .

[0234] Table 14

[0235]

[0236] Fig.22AThe axial chromatic aberration curve of the first state of the optical system 700 of Example 7 is shown, which indicates the deviation of the convergence point of light of different wavelengths after passing through the optical system 700. Fig. 22B The astigmatism curve of the first state of the optical system 700 of Example 7 is shown, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Fig. 22C The distortion curve of the first state of the optical system 700 of Example 7 is shown, which indicates the distortion magnitude values ​​corresponding to different image heights. Fig.22A , Fig. 22B and Fig. 22C It can be seen that the optical system 700 of Example 7 can achieve good imaging quality in the first state. Example 8

[0237] The following reference Fig.23 , Fig.24 , Fig.25A , Fig.25B and Fig.25C The optical system of Example 8 is described.

[0238] like Fig.23 and Fig.24 As shown, the optical system 800 may include a first element group G1, a second element group G2, and a third element group G3 arranged in sequence from the object side to the image side. The image side may be provided with an image plane IMA, for example. The imageable object distance range of the optical system 800 may be 10 cm to infinity. The magnification of the optical system 800 may be 8X.

[0239] The first element group G1 may include a first lens E1, a reflective element P, and a second lens E2. The second element group G2 may include an aperture STO, a third lens E3, a fourth lens E4, and a fifth lens E5. The third element group G3 may include a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 is located on the optical axis I and is arranged between the object side and the reflective element P. The second lens E2, the aperture STO, the third lens E3, the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7, and the eighth lens E8 are arranged in sequence from the reflective element P to the image side along the optical axis II. In one example, a filter E9 may be provided between the eighth lens E8 and the image plane IMA.

[0240] The positions of the first element group G1 and the second element group G2 on the optical axis II relative to the image plane IMA are fixed. The third element group G3 can move relative to the second element group G2 along the optical axis II. When the distance between the object and the optical system 800 changes from far to near, the distance between the third element group G3 and the second element group G2 on the optical axis II is adjusted, so that the optical system 800 can switch between the first state and the second state, thereby realizing the focusing function of the optical system 800. During the focusing process of the optical system 800, the maximum movement stroke of the third element group G3 can be 4.3025 mm.

[0241] The first lens E1 may have positive power, and its object side surface S1 is convex, and its image side surface S2 is convex. The reflective element P may have a reflective surface S3, and the reflective surface S3 is a plane. The second lens E2 may have negative power, and its object side surface S4 is concave, and its image side surface S5 is concave. The third lens E3 may have positive power, and its object side surface S6 is convex, and its image side surface S7 is convex. The fourth lens E4 may have negative power, and its object side surface S8 is convex, and its image side surface S9 is concave. The fifth lens E5 may have positive power, and its object side surface S10 is convex, and its image side surface S11 is convex. The sixth lens E6 may have negative power, and its object side surface S12 is concave, and its image side surface S13 is convex. The seventh lens E7 may have positive power, and its object side surface S14 is concave, and its image side surface S15 is convex. The eighth lens E8 may have negative power, and its object-side surface S16 is concave, and its image-side surface S17 is concave. The filter E9 may have an object-side surface S18 and an image-side surface S19. Light from the object passes through each surface S1 to S19 in sequence and is finally imaged on the image plane IMA.

[0242] Table 15 shows a basic parameter table of the optical system 800 of Example 8, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm).

[0243] Table 15

[0244]

[0245] In this embodiment, the positive and negative values ​​of the numerical signs of the radius of curvature of each surface only indicate the curvature direction of the surface. When the curvature directions of the surfaces of the lenses on the optical axis I and the optical axis II are the same, the positive and negative values ​​of the numerical signs of the radius of curvature of the surfaces are opposite. Similarly, the positive and negative values ​​of the numerical signs of the thickness / distance of each surface only indicate the direction. The curvature direction of each surface and the thickness / distance of each surface can be referred to Fig.23 and Fig.24 .

[0246] The on-axis distance W1 from the second element group G2 to the third element group G3 and the on-axis distance W2 from the third element group G3 to the filter E9 are variables, which may change as the distance between the object and the optical system 800 changes.

[0247] When the object is infinitely far from the optical system 800, the optical system 800 is in the first state. The structure diagram of the optical system 800 can be referred to Fig.23 , where W1=-1.1817mm, W2=-7.4147mm, effective focal length EFL of optical system 800=27.73mm, maximum field of view FOV of optical system 800=12.3122°, aperture value Fnox of optical system 800 in the first direction=1.9, aperture value Fnoy of optical system 800 in the second direction=1.9. When the object is at a predetermined distance from the optical system 800, the optical system 800 is in the second state. The structural diagram of the optical system 800 can be referred to Fig.24 .

[0248] In this embodiment, the object side surface and the image side surface of any lens from the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 16 shows the cone coefficient K and the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A59, A60, A61, A71, A72, A73, A74, A75 10 , A 12 , A 14 , A 16 , A 18 and A 20 .

[0249] Table 16

[0250]

[0251] Fig.25A The axial chromatic aberration curve of the first state of the optical system 800 of Example 8 is shown, which indicates the deviation of the convergence point of light rays of different wavelengths after passing through the optical system 800. Fig.25B The astigmatism curve of the first state of the optical system 800 of Example 8 is shown, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Fig.25C The distortion curve of the first state of the optical system 800 of Example 8 is shown, which indicates the distortion magnitude values ​​corresponding to different image heights. Fig.25A , Fig.25B and Fig.25C It can be seen that the optical system 800 of Example 8 can achieve good imaging quality in the first state. Example 9

[0252] The following reference Fig.26 , Fig. 27 , Fig.28A , Fig.28B and Fig.28C The optical system of Example 9 is described.

[0253] like Fig.26 and Fig. 27 As shown, the optical system 900 may include a first element group G1, a second element group G2, and a third element group G3 arranged in sequence from the object side to the image side. The image side may be provided with an image plane IMA, for example. The imageable object distance range of the optical system 900 may be 10 cm to infinity. The magnification of the optical system 900 may be 8X.

[0254] The first element group G1 may include a first lens E1, a reflective element P, and a second lens E2. The second element group G2 may include an aperture STO, a third lens E3, a fourth lens E4, and a fifth lens E5. The third element group G3 may include a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 is located on the optical axis I and is arranged between the object side and the reflective element P. The second lens E2, the aperture STO, the third lens E3, the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7, and the eighth lens E8 are arranged in sequence from the reflective element P to the image side along the optical axis II. In one example, a filter E9 may be provided between the eighth lens E8 and the image plane IMA.

[0255] The first element group G1 and the second element group G2 are fixed in position relative to the image plane IMA on the optical axis II. The third element group G3 can move relative to the second element group G2 along the optical axis II. When the distance between the object and the optical system 900 changes from far to near, the distance between the third element group G3 and the second element group G2 on the optical axis II is adjusted, so that the optical system 900 can switch between the first state and the second state, thereby realizing the focusing function of the optical system 900. During the focusing process of the optical system 900, the maximum movement stroke of the third element group G3 can be 3.5362 mm.

[0256] The first lens E1 may have positive power, and its object side surface S1 is convex, and its image side surface S2 is convex. The reflective element P may have a reflective surface S3, and the reflective surface S3 is a plane. The second lens E2 may have negative power, and its object side surface S4 is concave, and its image side surface S5 is concave. The third lens E3 may have positive power, and its object side surface S6 is convex, and its image side surface S7 is convex. The fourth lens E4 may have negative power, and its object side surface S8 is convex, and its image side surface S9 is concave. The fifth lens E5 may have positive power, and its object side surface S10 is convex, and its image side surface S11 is convex. The sixth lens E6 may have negative power, and its object side surface S12 is concave, and its image side surface S13 is convex. The seventh lens E7 may have positive power, and its object side surface S14 is concave, and its image side surface S15 is convex. The eighth lens E8 may have negative power, and its object-side surface S16 is concave, and its image-side surface S17 is convex. The filter E9 may have an object-side surface S18 and an image-side surface S19. Light from the object passes through each surface S1 to S19 in sequence and is finally imaged on the image plane IMA.

[0257] Table 17 shows a basic parameter table of the optical system 900 of Example 9, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm).

[0258] Table 17

[0259]

[0260] In this embodiment, the positive and negative values ​​of the numerical signs of the radius of curvature of each surface only indicate the curvature direction of the surface. When the curvature directions of the surfaces of the lenses on the optical axis I and the optical axis II are the same, the positive and negative values ​​of the numerical signs of the radius of curvature of the surfaces are opposite. Similarly, the positive and negative values ​​of the numerical signs of the thickness / distance of each surface only indicate the direction. The curvature direction of each surface and the thickness / distance of each surface can be referred to Fig.26 and Fig. 27 .

[0261] The on-axis distance W1 from the second element group G2 to the third element group G3 and the on-axis distance W2 from the third element group G3 to the filter E9 are variables, which may change as the distance between the object and the optical system 900 changes.

[0262] When the object is infinitely far from the optical system 900, the optical system 900 is in the first state. The structure diagram of the optical system 900 can be referred to Fig.26, where W1=-1.2964mm, W2=-7.0189mm, effective focal length EFL of optical system 900=27.73mm, maximum field of view FOV of optical system 900=12.3122°, aperture value Fnox of optical system 900 in the first direction=3.3, aperture value Fnoy of optical system 900 in the second direction=3.3. When the object is at a predetermined distance from the optical system 900, the optical system 900 is in the second state. The structure diagram of the optical system 900 can be referred to Fig. 27 .

[0263] In this embodiment, the object side surface and the image side surface of any lens from the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 18 shows the cone coefficient K and the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A59, A60, A61, A71, A72, A73, A74, A75 10 , A 12 , A 14 , A 16 , A 18 and A 20 .

[0264] Table 18

[0265]

[0266] Fig.28A The axial chromatic aberration curve of the first state of the optical system 900 of Example 9 is shown, which indicates the deviation of the convergence point of light rays of different wavelengths after passing through the optical system 900. Fig.28B The astigmatism curve of the first state of the optical system 900 of Example 9 is shown, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Fig.28C The distortion curve of the first state of the optical system 900 of Example 9 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Fig.28A , Fig.28B and Fig.28C It can be seen that the optical system 900 of Example 9 can achieve good imaging quality in the first state.

[0267] Table 19 shows the values ​​of parameters such as f1, f2, f3, f4, f5, f6, f7, f8, SL, SH, GH, D1, D2, D2x, D2y, fs1, fs2, SD1, SD2, FG12, FG3, EPDx, EPDy, α, β, etc. in each of Examples 1 to 9. Among them, SL, SH, GH, α, β can be calculated according to Figure 1A or Figure 1BThe units of parameters such as f1, f2, f3, f4, f5, f6, f7, f8, SL, SH, GH, D1, D2, D2x, D2y, fs1, fs2, SD1, SD2, FG12, FG3, EPDx, and EPDy in Table 19 are all millimeters (mm), and the units of α and β are degrees.

[0268] Table 19

[0269]

[0270] Table 20 shows the values ​​of the conditional expressions of each embodiment in Embodiments 1 to 9. It should be noted that the values ​​of the conditional expressions involving FOV, EFL, EPDx and EPDy in Table 20 are all calculated by the FOV, EFL, EPDx and EPDy of the optical system in the first state.

[0271] Table 20

[0272]

[0273] The present application also provides a camera module, which may be, for example, a periscope camera module. The camera module may include the above-mentioned optical system and an imaging element for converting an optical image formed by the optical system into an electrical signal.

[0274] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with (but not limited to) technical features with similar functions disclosed in the present application.

Claims

1. An optical system, characterized in that Along the optical axis from the object side to the image side, they include: A first element group, consisting of a first lens, a reflective element, and a second lens arranged in sequence from the object side to the image side, the first lens having positive optical power, the reflective element being used to reflect light emitted from the first lens, and the second lens having negative optical power; A second element group includes three lenses; and A third element group includes three lenses; The optical axis includes a first optical axis and a second optical axis at a preset angle, and the reflective element receives the light emitted from the first lens along the direction of the first optical axis, and reflects the light and emits it to the second lens along the direction of the second optical axis; The position of the second element group relative to the image plane arranged on the image side is fixed, and the distance between the third element group and the second element group on the second optical axis is adjustable; The optical system meets the following requirements: 0.6 <d1P / dP2<1.1,0.9<|FG12 / FG3|<1.1, Among them, d1P is the distance between the object side of the first lens and the reflective element along the first optical axis, dP2 is the distance between the reflective element and the image side of the second lens along the second optical axis, FG12 is the combined focal length of the first element group and the second element group, and FG3 is the effective focal length of the third element group.

2. The optical system according to claim 1, wherein: The optical system satisfies: |f1 / f2|≤1.0, Wherein, f1 is the effective focal length of the first lens, and f2 is the effective focal length of the second lens.

3. The optical system according to claim 1, wherein: The optical system also satisfies: 0.55≤|FG12 / EFL|≤0.67, Wherein, FG12 is the combined focal length of the first element group and the second element group, and EFL is the effective focal length of the optical system.

4. The optical system according to claim 1, wherein: The optical system also satisfies: 15.5mm<|EFL / (FG12 / FG3)|<35.0mm, Among them, FG12 is the combined focal length of the first element group and the second element group, FG3 is the effective focal length of the third element group, and EFL is the effective focal length of the optical system.

5. The optical system according to claim 1, wherein: The optical system also satisfies: 4.2 <D1 / CT1<6.6, Wherein, D1 is the maximum effective semi-aperture of the first lens, and CT1 is the center thickness of the first lens on the first optical axis.

6. The optical system according to claim 1, wherein: The optical system also satisfies: 2.2 <D2 / CT2<6.8, Wherein, D2 is the maximum effective semi-aperture of the second lens, and CT2 is the center thickness of the second lens on the second optical axis.

7. The optical system according to claim 1, wherein: The optical system also satisfies: 0.02mm -1 ≤D2x / EPDx / d12≤0.10mm -1 , Wherein, D2x is the maximum effective semi-aperture of the second lens in the first direction, EPDx is the entrance pupil diameter of the optical system in the first direction, d12 is the axial distance from the image side surface of the first lens to the object side surface of the second lens, and the first direction is perpendicular to the plane formed by the first optical axis and the second optical axis.

8. The optical system according to claim 1, wherein: The optical system also satisfies: 0.02mm -1 ≤D2y / EPDy / d12≤0.10mm -1 , Wherein, D2y is the maximum effective semi-aperture of the second lens in the second direction, EPDy is the entrance pupil diameter of the optical system in the second direction, d12 is the axial distance from the image side surface of the first lens to the object side surface of the second lens, and the second direction is parallel to the first optical axis.

9. The optical system according to claim 1, wherein: The optical system also satisfies: -0.60 <fs1 / fs2<1.85, Wherein, fs1 is the effective focal length of the object side of the first lens, and fs2 is the effective focal length of the image side of the first lens.

10. The optical system according to claim 1, wherein: The optical system also satisfies: 0.6 <EFL / SL<0.8, Wherein, EFL is the effective focal length of the optical system, and SL is the total length of the optical system along the direction of the second optical axis.

11. The optical system according to claim 1, wherein: The optical system also satisfies: 0.95≤SD1 / SD2≤1.12, SD1 is the maximum effective semi-aperture of the lens closest to the object side in the second element group, and SD2 is the maximum effective semi-aperture of another lens adjacent to the lens closest to the object side in the second element group.

12. The optical system according to claim 1, wherein: The optical system also satisfies: 0.1 <tan(FOV / 2)<0.4, Wherein, FOV is the maximum field of view of the optical system.

13. The optical system according to claim 1, wherein: The optical system also satisfies: OBJmin≥10cm, Wherein, OBJmin is the minimum value of the object distance of the optical system.

14. An optical system according to any one of claims 1 to 13, wherein: The reflective element includes a plane reflector.

15. An optical system according to any one of claims 1 to 13, wherein: The second element group includes a third lens with positive optical power, a fourth lens with negative optical power and a fifth lens with positive optical power, and the third element group includes a sixth lens with positive optical power or negative optical power, a seventh lens with positive optical power and an eighth lens with negative optical power.

16. A camera module, characterized in that: The optical system comprises the optical system as claimed in any one of claims 1 to 15 and an imaging element for converting an optical image formed by the optical system into an electrical signal.

Images