Optical system and camera module

Abstract

This application discloses an optical system and a camera module. The optical system includes a first element group, a second element group, and a third element group in sequence along the optical axis from the object side to the image side. The first element group is used to reflect light. The position of the second element group relative to the image plane disposed on the image side is fixed. The distance between the third element group and the second element group is adjustable. The combined focal length FG12 of the first element group and the second element group, the effective focal length FG3 of the third element group, and the effective focal length EFL of the optical system satisfy: 15.5mm < |EFL / (FG12 / FG3)| < 35.0mm.

Description

[0001] This application is a divisional application of the invention patent filed on September 18, 2024, with application number 2024113051537, entitled "Optical System and Camera Module". This application claims priority to the patent application filed on July 23, 2024, with application number 2024109933718, also entitled "Optical System and Camera Module". Technical Field

[0002] This invention relates to the field of optical devices, and more specifically, to an optical system and a camera module. Background Technology

[0003] With the rapid development of portable devices such as smartphones, telephoto lenses have been widely used due to their advantages such as clear imaging of distant objects, large magnification, and ability to present detailed features of objects.

[0004] The effective focal length of an optical system is a crucial criterion for determining whether it qualifies as a telephoto lens; the longer the effective focal length, the sharper distant objects appear in the image. However, the effective focal length is directly proportional to the required optical path length; that is, the longer the effective focal length, the greater the required optical path. Therefore, to achieve telephoto capabilities, existing optical systems typically have a large overall length, which severely limits their application in portable devices. Summary of the Invention

[0005] One aspect of this application provides an optical system comprising, sequentially from the object side to the image side, a first element group, a second element group, and a third element group along the optical axis. The first element group, from the object side to the image side, includes, in sequence, a first lens with positive optical power, a reflecting element, and a second lens with negative optical power. The reflecting element reflects 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 predetermined angle. The reflecting element receives light rays emitted from the first lens along the first optical axis and reflects them back to the second lens along the second optical axis. The position of the second element group relative to the image plane on the image side is fixed, while the distance between the third element group and the second element group on the second optical axis is adjustable. The distance dP2 between the image-side surfaces of the reflecting element and the second lens along the second optical axis satisfies 0.1 as the total length SL of the optical system along the second optical axis. <dP2 / SL<0.3。

[0006] According to an exemplary embodiment of this application, the reflective element includes a plane mirror.

[0007] According to an exemplary embodiment of this application, 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 or negative optical power, a seventh lens with positive optical power, and an eighth lens with negative optical power.

[0008] According to an exemplary embodiment of this application, the effective focal length f1 of the first lens and the effective focal length f2 of the second lens satisfy: |f1 / f2|≤1.0.

[0009] According to an exemplary embodiment of this application, the combined focal length FG12 of the first element group and the second element group satisfies the following condition with respect to the effective focal length EFL of the optical system: 0.55≤|FG12 / EFL|≤0.67.

[0010] According to an exemplary embodiment of this application, the combined focal length FG12 of the first element group and the second element group and the effective focal length FG3 of the third element group satisfy: 0.9 < |FG12 / FG3| < 1.1.

[0011] According to an exemplary embodiment of this application, the combined focal length FG12 of the first element group and the second element group, the effective focal length FG3 of the third element group, and the effective focal length EFL of the optical system satisfy: 15.5mm < |EFL / (FG12 / FG3)| < 35.0mm.

[0012] According to an exemplary embodiment of this application, the maximum effective half-aperture D1 of the first lens and the center thickness CT1 of the first lens on the first optical axis satisfy: 4.2 <D1 / CT1<6.6。

[0013] According to an exemplary embodiment of this application, the maximum effective half-aperture D2 of the second lens and the center thickness CT2 of the second lens on the second optical axis satisfy: 2.2 <D2 / CT2<6.8。

[0014] According to an exemplary embodiment of this application, the maximum effective half-aperture D2x of the second lens in the first direction, the entrance pupil diameter EPDx of the optical system in the first direction, and the axial distance d12 from the image-side surface of the first lens to the object-side surface of the second lens satisfy: 0.02 mm. -1 ≤D2x / EPDx / d12≤0.10mm -1 .

[0015] According to an exemplary embodiment of this application, the maximum effective half-aperture D2y of the second lens in the second direction, the entrance pupil diameter EPDy of the optical system in the second direction, and the axial distance d12 from the image-side surface of the first lens to the object-side surface of the second lens satisfy: 0.02mm. -1≤D2y / EPDy / d12≤0.10mm -1 .

[0016] According to an exemplary embodiment of this application, the effective focal length fs1 of the object-side surface of the first lens and the effective focal length fs2 of the image-side surface of the first lens satisfy: -0.60 <fs1 / fs2<1.85。

[0017] According to an exemplary embodiment of this application, the effective focal length EFL of the optical system and the total length SL of the optical system along the direction of the second optical axis satisfy: 0.6 <EFL / SL<0.8。

[0018] According to an exemplary embodiment of this application, the maximum effective half-aperture SD1 of the lens closest to the object side in the second element group and the maximum effective half-aperture SD2 of another lens adjacent to the lens closest to the object side in the second element group satisfy: 0.95≤SD1 / SD2≤1.12.

[0019] According to an exemplary embodiment of this application, the maximum field of view (FOV) of the optical system satisfies: 0.1 <Tan(FOV / 2)<0.4。

[0020] According to an exemplary embodiment of this application, the minimum object distance OBJmin of the optical system satisfies: OBJmin≥10cm.

[0021] Another aspect of this application provides a camera module that includes the aforementioned optical system and an imaging element for converting an optical image formed by the optical system into an electrical signal. Attached Figure Description

[0022] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings. Wherein:

[0023] Figure 1A A schematic diagram of the structure of the optical system according to this application is shown;

[0024] Figure 1B A schematic diagram of the optical path of light in the first element group is shown;

[0025] Figure 2 A schematic diagram of the structure of the optical system according to Embodiment 1 of this application in the first state is shown;

[0026] Figure 3 A schematic diagram of the structure of the optical system according to Embodiment 1 of this application in the second state is shown;

[0027] Figure 4A , Figure 4B and Figure 4CThe on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of Embodiment 1 of this application are shown respectively when the optical system is in the first state.

[0028] Figure 5 A schematic diagram of the structure of the optical system according to Embodiment 2 of this application in the first state is shown;

[0029] Figure 6 A schematic diagram of the structure of the optical system according to Embodiment 2 of this application in the second state is shown;

[0030] Figure 7A , Figure 7B and Figure 7C The on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of Embodiment 2 of this application are shown respectively when the optical system is in the first state.

[0031] Figure 8 A schematic diagram of the structure of the optical system according to Embodiment 3 of this application in the first state is shown;

[0032] Figure 9 A schematic diagram of the structure of the optical system according to Embodiment 3 of this application in the second state is shown;

[0033] Figure 10A , Figure 10B and Figure 10C The on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of Embodiment 3 of this application are shown respectively when the optical system is in the first state.

[0034] Figure 11 A schematic diagram of the structure of the optical system according to Embodiment 4 of this application in the first state is shown;

[0035] Figure 12 A schematic diagram of the structure of the optical system according to Embodiment 4 of this application in the second state is shown;

[0036] Figure 13A , Figure 13B and Figure 13C The on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of Embodiment 4 of this application in the first state are shown respectively.

[0037] Figure 14 A schematic diagram of the structure of the optical system according to Embodiment 5 of this application in the first state is shown;

[0038] Figure 15 A schematic diagram of the structure of the optical system according to Embodiment 5 of this application in the second state is shown;

[0039] Figure 16A , Figure 16B and Figure 16CThe on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of Embodiment 5 of this application are shown respectively when the optical system is in the first state.

[0040] Figure 17 A schematic diagram of the structure of the optical system according to Embodiment 6 of this application in the first state is shown;

[0041] Figure 18 A schematic diagram of the structure of the optical system according to Embodiment 6 of this application in the second state is shown;

[0042] Figure 19A , Figure 19B and Figure 19C The on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of Embodiment 6 of this application are shown respectively when the optical system is in the first state.

[0043] Figure 20 A schematic diagram of the structure of the optical system according to Embodiment 7 of this application in the first state is shown;

[0044] Figure 21 A schematic diagram of the structure of the optical system according to Embodiment 7 of this application in the second state is shown;

[0045] Figure 22A , Figure 22B and Figure 22C The on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of Embodiment 7 of this application are shown respectively when the optical system is in the first state.

[0046] Figure 23 A schematic diagram of the structure of the optical system according to Embodiment 8 of this application in the first state is shown;

[0047] Figure 24 A schematic diagram of the structure of the optical system according to Embodiment 8 of this application in the second state is shown;

[0048] Figure 25A , Figure 25B and Figure 25C The on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of Embodiment 8 of this application are shown respectively when the optical system is in the first state.

[0049] Figure 26 A schematic diagram of the structure of the optical system according to Embodiment 9 of this application in the first state is shown;

[0050] Figure 27 A schematic diagram of the optical system according to Embodiment 9 of this application in its second state is shown; and

[0051] Figure 28A , Figure 28B and Figure 28CThe on-axis chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of Embodiment 9 of this application in the first state are shown respectively.

[0052] Illustration:

[0053] 10, 100, 200, 300, 400, 500, 600, 700, 800, 900, optical system;

[0054] 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 stop; G1, First element group; G2, Second element group; G3, Third element group; IMA, Image plane. Detailed Implementation

[0055] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements.

[0056] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of this application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0057] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not drawn strictly to scale.

[0058] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0059] It should also be understood that the terms "comprising" 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. Furthermore, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0060] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formalized sense, unless expressly so specified herein.

[0061] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0062] Periscope camera modules are a common type of camera module used for long-distance shooting. The optical system within a periscope camera module can incorporate prisms. These prisms increase the effective focal length of the periscope camera module by folding the light path, thus meeting the requirements for long-focal-length shooting while reducing the overall length of the periscope camera module, achieving miniaturization.

[0063] Aperture is a crucial parameter for periscope camera modules, directly impacting their capabilities in low-light conditions, snapshots, background blur, and video recording. For instance, a large aperture periscope camera module can enhance background blur and highlight the subject, while also improving shutter speed and autofocus speed, ensuring better image quality.

[0064] However, current periscope camera modules still have some shortcomings in their optical systems. Due to the limitations of the prism's incident and exit surface sizes, the area of ​​the prism that receives light is limited. This results in less light entering the optical system and a smaller effective aperture, leading to problems such as poor low-light performance and inadequate bokeh in periscope camera modules. When the aperture of a periscope camera module increases, the size and weight of the prism also increase, resulting in a larger periscope camera module size and weight. Therefore, the requirement for a large aperture in periscope camera modules contradicts the trend towards miniaturization.

[0065] Furthermore, periscope camera modules typically achieve optical image stabilization by driving a prism with a motor. Larger and heavier prisms place greater demands on the motor's thrust, and they also occupy more space within the periscope camera module, resulting in less usable space for the motor and impacting its driving performance. The dual requirements of high driving force and limited installation space undoubtedly place higher demands on the motor.

[0066] In order to at least partially solve one or more of the above-mentioned problems and other potential problems, this application provides an optical system, specifically, an optical system that reduces the total height and total length of the optical system while achieving a large aperture, and improves the imaging quality and optical image stabilization performance of the optical system.

[0067] Figure 1A A schematic diagram of the optical system according to this application is shown. The optical system can be applied, for example, to a camera module, which can be, for example, a periscope camera module. It should be understood that the optical system can also be applied to other camera modules, and this application does not impose any specific limitations on this.

[0068] refer to Figure 1A The optical system 10 may sequentially include a first element group G1, a second element group G2, and a third element group G3 along the optical axis from the object side to the image side. The first element group G1 may include a first lens E1, a reflecting element P, and a second lens E2. The first lens E1 may have positive optical power. The reflecting element P is used to reflect light rays emitted from the first lens E1. The second lens E2 may have 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.

[0069] The first lens E1 converges the light rays, ensuring that the light remains converged after reflection by the reflecting element P, thereby increasing the amount of light entering the second lens E2. This increases the effective aperture of the optical system 10, improves its image quality, and reduces the effective aperture of the lenses in the rear element group (e.g., the second element group G2 and the third element group G3), decreasing the shoulder height of the rear element group and thus reducing the overall height of the optical system 10. Simultaneously, the second lens E2 enhances the optical image stabilization performance of the optical system 10.

[0070] In an exemplary embodiment, the first lens E1 may have positive optical power and is used to converge light rays. By making the first lens E1 converge light rays, the light rays remain in a converged state after being reflected by the reflecting element P, increasing the amount of light rays entering the second lens E2. This increases the effective aperture (i.e., the amount of light entering) of the optical system 10 without changing the physical aperture of the stop STO. In other words, under the same lighting 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 low-light environments, the large-aperture optical system 10 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 low-light environments.

[0071] Simultaneously, the first lens E1 converges the light rays, and the converged light rays remain in a converged state after being reflected by the reflecting element P. This helps to reduce the effective aperture of the second lens E2, and ensures that the aperture of the light rays exiting from the second lens E2 is still smaller than the aperture of the light rays entering the second element group G2 than when the light rays enter the first lens E1. This reduces the effective aperture of the lenses in the rear element group (e.g., the second element group G2 and the third element group G3), thereby reducing the shoulder height of the rear 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 element group affects the thickness of the electronic device. Therefore, reducing the shoulder height of the rear element group helps to reduce the thickness of the electronic device and meet the design requirements of miniaturization.

[0072] Furthermore, compared to parallel light rays, the light rays converged by the first lens E1 have a reflection point closer to the optical axis at the outermost edge of the reflective element P. This allows the reflective element P to be made smaller, further reducing the height of the reflective element P and decreasing the overall height of the optical system 10.

[0073] In an exemplary implementation, reference Figure 1A The reflecting element P is positioned at any desired angle to bend the light path. The reflecting element P can be configured to deflect the incident light path by a predetermined degree (e.g., but not limited to 90°), for example, causing the incident light path to change from propagating along a first optical axis (hereinafter referred to as optical axis I) to propagating along a second optical axis (hereinafter referred to as optical axis II). It should be understood that the optical axis in this document may include a first optical axis and a second optical axis at a predetermined angle.

[0074] In an exemplary implementation, reference Figure 1AThe reflecting element P can be disposed between the first lens E1 and the second lens E2. That is, the first lens E1 can be located on the optical axis I and disposed between the object side and the reflecting element P, and the second lens E2 can be located on the optical axis II and disposed between the reflecting element P and the second element group G2. The reflecting element P can receive the light emitted from the first lens E1 along the optical axis I, and reflect the light and emit it into the second lens E2 along the optical axis II. The optical axis I and the optical axis II are at a predetermined angle, for example, but not limited to, the optical axis I and the optical axis II are perpendicular.

[0075] In an exemplary implementation, reference Figure 1A The reflecting element P can be a plane mirror, which may have a reflecting surface. Light rays emitted from the first lens E1 along optical axis I are totally internally reflected by the reflecting surface of the reflecting element P and emitted along optical axis II into the second lens E2. The reflecting surface of the reflecting element P passes through the intersection of optical axis I and optical axis II; that is, the reflecting surface of the reflecting element P is located on both optical axis I and optical axis II. By using a plane mirror with relatively small weight and size as the reflecting element, while achieving a large aperture in the optical system 10, the weight and size of the first element group G1 can be constrained within a certain range, minimizing the weight and size of the optical system 10 and reducing the driving burden on the reflecting element P.

[0076] It should be understood that the plane mirror only has a reflective surface, and the positions facing the light-incident side and the light-outcident side are empty. When the first lens E1 is set, the first lens E1 can be made closer to the plane mirror, reducing the height space occupied by the first lens E1 and the reflective element P, thereby reducing the total height of the optical system 10.

[0077] In an exemplary embodiment, the second lens E2 may have negative optical power and expand the beam of light reflected by the reflecting element P. By making the second lens E2 have a beam-expanding effect on light, the light emitted from the second lens E2 can be incident on the second element group G2 in a direction that is close to parallel to the optical axis II. That is, the light at each edge position propagates in a direction that is close to parallel to the optical axis II, ensuring that the effective aperture of the lens in the rear element group (e.g., the second element group G2 and the third element group G3) is close to the effective aperture of the second lens E2. Under the beam-contracting effect of the first lens E1, 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.

[0078] Simultaneously, by setting a second lens E2 that expands the light beam, when the reflective element P is driven to achieve optical image stabilization, the movement of the reflective element P has a relatively small impact on the position of the light on the second element group G2. This results in a smaller drop in the MTF of the optical system 10, i.e., lower image stabilization sensitivity. Specifically, the second lens E2 expands the light beam, increasing the coverage area of ​​the light on the second element group G2. Furthermore, the pre-diffused light is not concentrated in a very small area. Therefore, even if the reflective element P moves during optical image stabilization, this movement has a relatively small impact on the position of the light on the second element group G2, resulting in a smaller drop in the MTF of the optical system 10, i.e., lower image stabilization sensitivity.

[0079] If the second lens E2 has no optical power or only positive optical power, the light reflected by the reflecting element P directly reaches the second element group G2, and the light is still converging towards the center when it reaches the second element group G2. This results in a smaller coverage area of ​​the light reaching the second element group G2. In this case, the light reaching the second element group G2 is relatively concentrated. If the reflecting element P moves during optical image stabilization, this movement will significantly affect the position of the light in the second element group G2, leading to a larger drop in the MTF of the optical system 10, i.e., higher image stabilization sensitivity.

[0080] In an exemplary embodiment, a gap may exist between the first lens E1 and the reflecting element P. A gap may also exist between the second lens E2 and the reflecting element P. By creating gaps between the first lens E1, the second lens E2, and the reflecting element P, multiple options can be provided for the surface design of the side of the first lens E1 and the second lens E2 closest to the reflecting element P, thereby improving the flexibility of the surface design of the side of the first lens E1 and the second lens E2 closest to the reflecting element P.

[0081] It should be understood that the gap between the first lens E1 and the reflecting element P refers to a certain gap between the surface of the first lens E1 closest to the reflecting element P and at least a portion of the reflecting element P, not that the first lens E1 and the reflecting element P are completely out of contact. Similarly, the gap between the second lens E2 and the reflecting element P refers to a certain gap between the surface of the second lens E2 closest to the reflecting element P and at least a portion of the reflecting element P, not that the second lens E2 and the reflecting element P are completely out of contact.

[0082] In an exemplary embodiment, at least one surface of the first lens E1 and / or the second lens E2 is an aspherical surface. An aspherical lens is characterized by a continuously changing curvature from its center to its periphery. Unlike a spherical lens, which has a constant curvature from its center to its periphery, an aspherical lens has superior curvature radius characteristics, offering advantages in improving distortion and astigmatism. By using an aspherical lens, aberrations occurring during imaging can be eliminated as much as possible, thereby improving image quality.

[0083] As an example, the object side of the first lens E1 can be convex, and the image side can be either convex or concave.

[0084] As an example, the object side of the second lens E2 can be convex or concave, and the image side can be convex or concave.

[0085] In an exemplary implementation, 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 sequentially from the object side to the image side. The third lens E3, the fourth lens E4, and the fifth lens E5 may be arranged sequentially along the optical axis II from the second lens E2 to the image side.

[0086] As an example, the third lens E3 can have positive optical power. The fourth lens E4 can have negative optical power. The fifth lens E5 can have positive optical power.

[0087] As an example, the second element group G2 may also include an aperture stop STO, which may be disposed, for example, between the second lens E2 and the third lens E3.

[0088] It should be understood that the number of lenses included in the second element group G2 being three is merely exemplary, and this application does not impose any specific limitation on the number of lenses included in the second element group G2.

[0089] In an exemplary implementation, 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 sequentially from the object side to the image side. The sixth lens E6, the seventh lens E7, and the eighth lens E8 may be arranged sequentially along the optical axis II from the fifth lens E5 to the image side.

[0090] As an example, the sixth lens E6 can have positive or negative optical power. The seventh lens E7 can have positive optical power. The eighth lens E8 can have negative optical power.

[0091] It should be understood that the number of lenses included in the third element group G3 is merely exemplary, and this application does not impose any specific limitation on the number of lenses included in the third element group G3.

[0092] In an exemplary implementation, reference Figure 1A The optical system 10 may also 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.

[0093] In an exemplary implementation, reference Figure 1A When light enters the optical system 10, it first enters the first lens E1 along the optical axis I and is converged by the first lens E1 to reach the reflecting element P. Then, it is totally reflected by the reflecting element P and turns to enter the second lens E2 along the optical axis II. After exiting the second lens E2, the light 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 then reaches the filter E9. After passing through the filter E9, it finally reaches the image plane IMA.

[0094] By employing a first lens E1, a reflective element P, and a second lens E2, the aperture of the optical system 10 can be increased, enabling the optical system 10 to obtain higher image plane brightness, and improving the imaging quality and optical image stabilization performance of the optical system 10, while also reducing the weight and size of the optical system 10.

[0095] In an exemplary implementation, reference Figure 1A The second element group G2 can be fixed in position relative to the image plane IMA on the optical axis (e.g., optical axis II). The third element group G3 can move relative to the second element group G2 along the optical axis (e.g., optical axis II), meaning the distance between the third element group G3 and the second element group G2 on the optical axis (e.g., optical axis II) is adjustable. When the subject moves from far to near the optical system 10, adjusting the distance between the third element group G3 and the second element group G2 on the optical axis (e.g., optical axis II) allows the optical system 10 to switch between a first state and a second state, thus achieving the focusing function of the optical system 10. For example, when the subject is infinitely far from the optical system 10, the optical system 10 is in the first state (e.g., long-distance state); when the subject is a preset distance from the optical system 10, the optical system 10 is in the second state (e.g., short-distance state). By making the second element group G2 a fixed group and the third element group G3 a moving group, the motor travel can be shortened during the focusing process of the optical system 10, improving the image quality of the optical system 10. As an example, the first element group G1 can be fixed at a position relative to the image plane IMA on the optical axis (such as optical axis II).

[0096] In an exemplary implementation, reference Figure 2 and Figure 3When the subject moves from far to near the optical system 10, 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 subject moves from near to far from the optical system 10, the third element group G3 can move along the optical axis II in a direction closer to the second element group G2, so that the optical system 10 switches from the second state to the first state.

[0097] In an exemplary embodiment, during the focusing process of the optical system 10, the maximum travel distance of the third element group G3 can be in the range of 1.0 mm to 7.0 mm.

[0098] In an exemplary embodiment, the optical system 10 may further include a lens barrel assembly (not shown). The lens barrel assembly may include a first lens barrel, a second lens barrel, and a third lens barrel. A first element group G1 may be fixed inside the first lens barrel. A second element group G2 may be fixed inside the second lens barrel. A third element group G3 may be fixed inside the third lens barrel. The first lens barrel has a first opening on the light-incident side and a second opening on the light-outcident side. A first lens E1 is disposed inside the first opening, a second lens E2 is disposed inside the second opening, and a reflecting element P is disposed between the first opening and the second opening. The inner diameter of the first opening is larger 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 portions of the second lens barrel corresponding to different lenses are different. The inner diameters of the portions of the third lens barrel corresponding to different lenses are different.

[0099] During the focusing process of the optical system 10, the second lens barrel and the second element group G2 can be fixed in position relative to the image plane IMA on the optical axis II, while the third lens barrel and the third element group G3 can move away from the second element group G2 along the optical axis II, or the third lens barrel and the third element group G3 can move closer to the second element group G2 along the optical axis II. It should be understood that when the optical system 10 performs the focusing function, the third lens barrel and the third element group G3 can be moved along the optical axis II by a motor (not shown), while 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 in position relative to the image plane IMA on the optical axis II.

[0100] In an exemplary embodiment, the optical system 10 may further include a lens barrel assembly (not shown). A second element group G2 may be fixed within the lens barrel assembly. A third element group G3 may be movably disposed within the lens barrel assembly. During focusing of the optical system 10, the lens barrel assembly and the second element group G2 may be fixed at positions relative to 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 closer to the second element group G2. It should be understood that when the optical system 10 performs the focusing function, the third element group G3 may be moved along the optical axis II by a motor (not shown), while the lens barrel assembly and the second element group G2 remain stationary. As an example, a first element group G1 may be fixed within the lens barrel assembly.

[0101] In an exemplary embodiment, when light enters the optical system 10, due to the converging effect of the first lens E1, the light exits from the first lens E1 in a converging state, and after being reflected by the reflecting element P, it still reaches the second lens E2 in the same converging state. However, due to the expanding effect of the second lens E2, the convergence angle of the light after exiting the second lens E2 is reduced (e.g., the convergence angle of the light after exiting the second lens E2 is smaller than the convergence angle of the light by the first lens E1). Simultaneously, the gap between the second lens E2 and the third lens E3 is smaller. Therefore, the effective aperture of the third lens E3 is closer 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 (e.g., the second element group G2 and the third element group G3) is typically related to the maximum effective aperture of the third lens E3 in the second direction, or to the maximum aperture diameter of the aperture stop STO in the second direction.

[0102] Figure 1B A schematic diagram of the light path in the first element group is shown. It should be noted that, for ease of illustration, Figure 1B The reflecting element P is omitted, and the first lens E1 is rotated onto the optical axis II. The actual structural diagram of the first element group should be similar to... Figure 1A .

[0103] As an example, see reference Figure 1A and Figure 1B, the included angle α between the outgoing light ray B1 corresponding to the first lens E1 and the incident light ray A1 corresponding to the first lens E1 and the axial distance d12 from the image side of the first lens E1 to the object side of the second lens E2 can satisfy: 0.1 < Tan(α) × d12 < 1.8. The incident light ray A1 corresponding to the first lens E1 can be, for example, a parallel light ray. The product of Tan(α) and d12 is approximately equal to the difference in the maximum effective semi-aperture between the first lens E1 and the second lens E2. The larger the value of α, the better the light converging effect of the first lens E1, and the larger the difference in the maximum effective semi-aperture between the first lens E1 and the second lens E2. By controlling the above conditional expression, it is possible to make the first lens E1 have a strong light converging ability, ensure 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 aperture of the lenses 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, 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.

[0104] 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 converging effect of the first lens E1, thereby causing the difference in the maximum effective semi-aperture between the first lens E1 and the second lens E2 to be too small, the shoulder height of the rear element group to be too large, and the total height of the optical system 10 to be too large. If the value of Tan(α) × d12 is greater than 1.8, it will result in an overly high 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 the total length of the optical system 10 to be too high.

[0105] As an example, refer to Figure 1A and Figure 1B, the included angle α between the outgoing light ray B1 corresponding to the first lens E1 and the incident light ray A1 corresponding to the first lens E1, the included angle β between the outgoing light ray B2 corresponding to the second lens E2 and the incident light ray A1 corresponding to the first lens E1, and the axial distance d12 from the image side surface of the first lens E1 to the object side surface of the second lens E2 and the axial distance d23 from the image side surface of the second lens E2 to the object side surface of the third lens E3 can satisfy: 0.1 < Tan(α) × d12 + Tan(β) × d23 < 1.7. The incident light ray A1 corresponding to the first lens E1 can be, for example, a parallel light ray. 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 converging 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 included angle between the light ray 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 restricting Tan(α) × d12 + Tan(β) × d23 within the range of 0.1 to 1.7, it is possible to make the first lens E1 have a strong light converging ability, ensure that the light ray 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.

[0106] In an exemplary embodiment, referring to Figure 1A , the axial distance d1P from the object side surface of the first lens E1 to the reflecting element P, the axial distance dP2 from the reflecting element P to the image side surface of the second lens E2, and the total height SH of the optical system 10 can satisfy: 1.1 < (d1P + dP2) / SH < 1.6. d1P and dP2 are related to the light converging ability of the first element group G1. Generally speaking, the larger the value of d1P + dP2, the stronger the light converging ability of the first element group G1. By controlling the above conditional formula, it is beneficial to ensure that the first element group G1 has a good light converging ability, and to reasonably arrange the positions of the first lens E1, the reflecting element P, and the second lens E2, so as to avoid interference between the reflecting element P and the first lens E1 and the second lens E2; at the same time, it is also possible to reduce the total height of the optical system 10 when the total length of the optical system 10 meets the design requirements and the reflecting element P does not interfere with the first lens E1 and the second lens E2. Further, 2.9 mm < d1P < 10.4 mm.

[0107] When the value of (d1P + dP2) / SH is less than 1.1, the value of d1P + dP2 is too small, resulting in a poor light convergence ability of the first element group G1 and excessive shoulder heights of the rear element group and the total height of the optical system 10; or when the value of (d1P + dP2) / SH is less than 1.1, the value of SH is too large, resulting in an excessive total height of the optical system 10. When the value of (d1P + dP2) / SH is greater than 1.6, the value of d1P + dP2 is too large, resulting in an excessive total length of the optical system 10. The total height and the total length of the optical system 10 are mutually restrictive. By controlling (d1P + dP2) / SH within the range of 1.1 to 1.6, it is beneficial to reduce the total height and the total length of the optical system 10.

[0108] In an exemplary embodiment, referring to Figure 1A , the on-axis distance dP2 from the reflection element P to the image side surface of the second lens E2 and the total length SL of the optical system 10 along the direction of the second optical axis may satisfy: 0.1 < dP2 / SL < 0.3. By controlling the above conditional expression, 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 convergence effect, reduce the shoulder heights of the rear element group (for example, the second element group G2 and the third element group G3), and further reduce the total height of the optical system 10. d1P, dP2 are related to the light convergence ability of the first element group G1. The larger the value of d1P + dP2, the stronger the light convergence ability of the first element group G1. When the value of d1P + dP2 is fixed, as the value of dP2 increases, the value of d1P decreases. While ensuring that the first element group G1 has a good light convergence effect, it is beneficial to reduce the shoulder heights of the rear element group and the total height of the optical system 10.

[0109] 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 convergence ability of the first element group G1 and excessive shoulder heights of the rear element group and the 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 an excessive 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 an excessive total length of the optical system 10. The total height and the total length of the optical system 10 are mutually restrictive. By controlling dP2 / SL 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.

[0110] In an exemplary embodiment, the on-axis distance d1P from the object side surface of the first lens E1 to the reflecting element P and the on-axis distance dP2 from the reflecting element P to the image side surface of the second lens E2 may satisfy: 0.6 < d1P / dP2 < 1.1. By controlling the above conditional expression, 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 on light, and to 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.

[0111] When the value of d1P / dP2 is less than 0.6, the value of dP2 is too large, resulting in an overly 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 a poor light converging ability of the first element group G1, an overly large shoulder height of the rear element group, and an overly large 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 overly large total height of the optical system 10. The total height and the total length of the optical system 10 restrict each other. By controlling d1P / dP2 within the range of 0.6 to 1.1, it is beneficial to reduce the total height and the total length of the optical system 10.

[0112] In an exemplary embodiment, the effective focal length f1 of the first lens E1 and the effective focal length f2 of the second lens E2 may satisfy: |f1 / f2| ≤ 1.0. By controlling the above conditional expression, it is possible to make the first lens E1 have a strong light converging ability, a strong effect on expanding the aperture, and ensure 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 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 total height of the optical system 10; at the same time, it can also make the angle between the light exiting from the second lens E2 and the optical axis II within a small range, improving the optical anti-shake performance of the optical system 10.

[0113] In an exemplary embodiment, the combined focal length FG12 of the first element group G1 and the second element group G2 and the effective focal length EFL of the optical system 10 may satisfy: 0.55 ≤ |FG12 / EFL| ≤ 0.67. By controlling the above conditional expression, the optical system 10 can image an object relatively close to the optical system 10, ensuring that the optical system 10 has a relatively large range of object distances for imaging; at the same time, it can also enable the first element group G1 to have a certain light converging ability, which is beneficial to reducing the shoulder height of the second element group G2, and ensuring that the light enters the second element group G2 at a direction with a relatively small angle with respect to the optical axis II after passing through the first element group G1, improving the optical anti-shake performance of the optical system 10.

[0114] In an exemplary embodiment, the combined focal length FG12 of the first element group G1 and the second element group G2 and the effective focal length FG3 of the third element group G3 may satisfy: 0.9 < |FG12 / FG3| < 1.1. 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 distributed, improving the imaging performance of the optical system 10 for an object relatively close to the optical system 10, and expanding the range of object distances for imaging of the optical system 10.

[0115] In an exemplary embodiment, the combined focal length FG12 of the first element group G1 and the second element group G2, the effective focal length FG3 of the third element group G3 and the effective focal length EFL of the optical system 10 may satisfy: 15.5 mm < |EFL / (FG12 / FG3)| < 35.0 mm. 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 distributed, ensuring that the optical system 10 can achieve optimal focusing through the limited movement of the moving element group when imaging 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 for imaging of the optical system 10.

[0116] In an exemplary embodiment, the maximum effective semi-aperture D1 of the first lens E1 and the central thickness CT1 of the first lens E1 on the optical axis (such as the optical axis I) may satisfy: 4.2 < D1 / CT1 < 6.6. D1 may be, for example, the maximum value 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 controlling the above conditional expression, 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.

[0117] In an exemplary embodiment, the maximum effective semi-aperture D2 of the second lens E2 and the central thickness CT2 of the second lens E2 on the optical axis (such as optical axis II) may satisfy: 2.2 < D2 / CT2 < 6.8. 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 controlling the above conditional expression, when the workability 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 anti-shake performance of the optical system 10.

[0118] 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.

[0119] In an exemplary embodiment, the maximum effective semi-aperture D2x of the second lens E2 in the first direction, the entrance pupil diameter EPDx of the optical system 10 in the first direction, and the on-axis distance d12 from the image side of the first lens E1 to the object side of the second lens E2 may satisfy: 0.02 mm -1 ≤ D2x / EPDx / d12 ≤ 0.10 mm -1 . 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 requirements of a large aperture, 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.

[0120] In an exemplary embodiment, the maximum effective semi-aperture D2y of the second lens E2 in the second direction, the entrance pupil diameter EPDy of the optical system 10 in the second direction, and the on-axis distance d12 from the image side of the first lens E1 to the object side of the second lens E2 may satisfy: 0.02 mm -1 ≤ D2y / EPDy / d12 ≤ 0.10 mm -1. D2y can be, for example, the maximum value of the effective semi-aperture of the object side and the effective semi-aperture of 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 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 shoulder height of the rear-end element group (for example, the second element group G2 and the third element group G3), thereby reducing the overall height of the optical system 10.

[0121] In an exemplary embodiment, the effective focal length fs1 of the object side of the first lens E1 and the effective focal length fs2 of the image side of the first lens E1 can satisfy: -0.60 < fs1 / fs2 < 1.85. By controlling the above conditional expression, the first lens E1 can have sufficient converging ability, and the surface shape trends of the object side and the image side of the first lens E1 can be restricted, thereby reducing the shoulder height of the rear-end element group (for example, the second element group G2 and the third element group G3) and reducing the overall height of the optical system 10.

[0122] In an exemplary embodiment, referring to Figure 1A , the effective focal length EFL of the optical system 10 and the total length SL of the optical system 10 along the direction of the second optical axis can satisfy: 0.6 < EFL / SL < 0.8. By controlling the above conditional expression, when the optical system 10 realizes characteristics such as long focal length, large aperture, and a certain image plane size, it is beneficial to shorten the total length of the optical system 10, thereby reducing the volume of the optical system 10.

[0123] In an exemplary embodiment, the maximum effective semi-aperture SD1 of the lens closest to the object side in the second element group G2 and the maximum effective semi-aperture SD2 of another lens adjacent to the lens closest to the object side in the second element group G2 can satisfy: 0.95 ≤ SD1 / SD2 ≤ 1.12. 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 the lens can be, for example, the maximum value of the effective semi-aperture of the object side and the effective semi-aperture of the image side of the lens. By controlling the above conditional expression, while ensuring the performance of the optical system 10, it is beneficial to reduce the overall height of the optical system 10.

[0124] In an exemplary embodiment, the maximum field angle FOV of the optical system 10 can satisfy: 0.1 < Tan(FOV / 2) < 0.4. By controlling the above conditional expression, the optical system 10 can have a smaller field angle, which is beneficial to the optical system 10 to image distant objects, thereby ensuring good imaging quality of the optical system 10 at a long distance.

[0125] In an exemplary embodiment, the minimum object distance OBJmin of the optical system 10 can satisfy: OBJmin ≥ 10cm. The object distance can be, for example, the distance between the object being photographed and the optical system 10. As an example, 10cm ≤ OBJmin < 20cm. By controlling the above condition, the optical system 10 can image under the condition that the object distance is greater than or equal to 10cm, and the imaging effect is good.

[0126] 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.

[0127] The optical system 10 according to the above embodiments of this application can employ eight lenses and one reflective element. By rationally allocating the optical parameters of each lens and reflective element, while ensuring the size of the optical system 10 meets the requirements, it is beneficial for the optical system 10 to achieve characteristics such as telephoto 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.

[0128] In this 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 (e.g., the second element group G2 and the third element group G3). Specifically, GH is determined by the maximum effective aperture of the lenses within the second element group G2 and the third element group G3 in the second direction (e.g., 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 (e.g., 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 reflecting element P along the optical axis I, and the distance between the reflecting element P and the object-side surface of the second lens E2 along the optical axis II. d1P represents the axial distance from the object-side surface of the first lens E1 to the reflecting element P. Specifically, d1P is the distance between the object-side surface of the first lens E1 and the reflecting element P along optical axis I. dP2 represents the axial distance from the reflecting element P to the image-side surface of the second lens E2. Specifically, dP2 is the distance between the image-side surfaces of the reflecting element P and the second lens E2 along optical axis II. The modulation transfer function (MTF) is an important indicator describing the imaging quality of the optical system 10, and the MTF can be obtained through simulation. The optical image stabilization (OIS) sensitivity is a drop in MTF, which represents the difference between the MTF and the static MTF design value per unit jitter angle.

[0129] Those skilled in the art will understand that, without departing from the technical solutions claimed in this application, the number of lenses constituting the optical system 10 can be changed to obtain the various results and advantages described in this specification.

[0130] Specific embodiments of the optical system applicable to the above-described embodiments are further described below with reference to the accompanying drawings.

[0131] Example 1

[0132] The following is for reference Figure 2 , Figure 3 , Figure 4A , Figure 4B and Figure 4C The optical system of Example 1 is described.

[0133] 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 sequentially from the object side to the image side. An image plane IMA may be provided on the image side, for example. The imageable object distance range of the optical system 100 can be from 17 cm to infinity. The magnification of the optical system 100 can be 2.5X.

[0134] The first element group G1 may include a first lens E1, a reflecting element P, and a second lens E2. The second element group G2 may include an aperture stop 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 disposed between the object side and the reflecting element P. The second lens E2, aperture stop STO, third lens E3, fourth lens E4, fifth lens E5, sixth lens E6, seventh lens E7, and eighth lens E8 are arranged sequentially along the optical axis II from the reflecting element P to the image side. In one example, a filter E9 may be disposed between the eighth lens E8 and the image plane IMA.

[0135] 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 subject moves from far to near the optical system 100, adjusting the distance between the third element group G3 and the second element group G2 on the optical axis II allows the optical system 100 to switch between a first state and a second state, thereby achieving the focusing function of the optical system 100. During the focusing process of the optical system 100, the maximum travel distance of the third element group G3 can be 1.0898 mm.

[0136] The first lens E1 can have positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The reflecting element P can have a reflecting surface S3, and the reflecting surface S3 is planar. The second lens E2 can have negative optical power, with its object-side surface S4 being convex and its image-side surface S5 being concave. The third lens E3 can have positive optical power, with its object-side surface S6 being convex and its image-side surface S7 being convex. The fourth lens E4 can have negative optical power, with its object-side surface S8 being convex and its image-side surface S9 being concave. The fifth lens E5 can have positive optical power, with its object-side surface S10 being concave and its image-side surface S11 being convex. The sixth lens E6 can have positive optical power, with its object-side surface S12 being concave and its image-side surface S13 being convex. The seventh lens E7 can have positive optical power, with its object-side surface S14 being concave and its image-side surface S15 being convex. The eighth lens E8 can have negative optical power, with its object-side surface S16 being convex and its image-side surface S17 being concave. The filter E9 can have an object-side surface S18 and an image-side surface S19. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the image plane IMA.

[0137] Table 1 shows the basic parameters of the optical system 100 of Embodiment 1, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0138] Table 1

[0139]

[0140]

[0141] In this embodiment, the sign of the numerical value of the radius of curvature of each surface indicates only the direction of curvature. When the curvature directions of the lenses on optical axis I and optical axis II are the same, the signs of the numerical values ​​of the radii of curvature are opposite. Similarly, the sign of the numerical value of the thickness / distance of each surface indicates only the direction. The curvature direction of each surface and the thickness / distance of each surface can be found by referring to... Figure 2 and Figure 3 .

[0142] Among them, the on-axis distance W1 between the second element group G2 and the third element group G3, and the on-axis distance W2 between the third element group G3 and the filter E9 are variables that can change with the distance between the subject and the optical system 100.

[0143] When the subject is infinitely far from the optical system 100, the optical system 100 is in its first state. A structural diagram of the optical system 100 can be found here. Figure 2Wherein, W1 = -1.0163mm, W2 = -4.5910mm, the effective focal length (EFL) of the optical system 100 is 15.20mm, the maximum field of view (FOV) of the optical system 100 is 41.72°, the aperture value (Fnox) of the optical system 100 in the first direction is 2.34, and the aperture value (Fnoy) of the optical system 100 in the second direction is 3.35. When the subject is at a predetermined distance from the optical system 100, the optical system 100 is in its second state. A structural diagram of the optical system 100 can be found here. Figure 3 .

[0144] In this embodiment, the object-side surface and image-side surface of any one of the first lens E1 to the eighth lens E8 are aspherical. The surface shape of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0145]

[0146] Where X(Y) represents the relative distance between a point on the aspherical surface at a distance Y from the optical axis and the tangent plane at the intersection point on the optical axis; Y represents the perpendicular distance between a point on the aspherical curve and the optical axis; R represents the radius of curvature; K represents the conic coefficient; A m Let represent the i-th order Qcon aspheric coefficient; u = (Y / NR), where NR represents the normalized radius of the Qcon aspheric surface; Let represent the m-th order Qcon polynomial. Table 2 gives the conic coefficients K and higher-order coefficients A4, A6, A8, A17 that can be used for each aspherical surface S1-S2, S4-S17 in Example 1. 10 A 12 A 14 A 16 A 18 and A 20 .

[0147] Table 2

[0148]

[0149]

[0150] Figure 4A The on-axis chromatic aberration curve of the optical system 100 of Embodiment 1 in its first state is shown, which represents the deflection of the focal point of light of different wavelengths after passing through the optical system 100. Figure 4B The astigmatism curve of the optical system 100 of Embodiment 1 in its first state is shown, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 4C The distortion curve of the optical system 100 of Embodiment 1 in its first state is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 4A , Figure 4B and Figure 4C It can be seen that the optical system 100 of Embodiment 1 can achieve good imaging quality in the first state.

[0151] Example 2

[0152] The following is for reference Figure 5 , Figure 6 , Figure 7A , Figure 7B and Figure 7C The optical system of Example 2 is described.

[0153] 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 sequentially from the object side to the image side. An image plane IMA may be provided on the image side, for example. The imageable object distance range of the optical system 200 can be from 10 cm to infinity. The magnification of the optical system 200 can be 5X.

[0154] The first element group G1 may include a first lens E1, a reflecting element P, and a second lens E2. The second element group G2 may include an aperture stop 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 disposed between the object side and the reflecting element P. The second lens E2, aperture stop STO, third lens E3, fourth lens E4, fifth lens E5, sixth lens E6, seventh lens E7, and eighth lens E8 are arranged sequentially along the optical axis II from the reflecting element P to the image side. In one example, a filter E9 may be disposed between the eighth lens E8 and the image plane IMA.

[0155] 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 subject moves from far to near the optical system 200, adjusting the distance between the third element group G3 and the second element group G2 on the optical axis II allows the optical system 200 to switch between a first state and a second state, thereby achieving the focusing function of the optical system 200. During the focusing process of the optical system 200, the maximum travel distance of the third element group G3 can be 6.4288 mm.

[0156] The first lens E1 can have positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being convex. The reflecting element P can have a reflecting surface S3, and the reflecting surface S3 is planar. The second lens E2 can have negative optical power, with its object-side surface S4 being concave and its image-side surface S5 being concave. The third lens E3 can have positive optical power, with its object-side surface S6 being convex and its image-side surface S7 being convex. The fourth lens E4 can have negative optical power, with its object-side surface S8 being convex and its image-side surface S9 being concave. The fifth lens E5 can have positive optical power, with its object-side surface S10 being convex and its image-side surface S11 being convex. The sixth lens E6 can have negative optical power, with its object-side surface S12 being concave and its image-side surface S13 being convex. The seventh lens E7 can have positive optical power, with its object-side surface S14 being convex and its image-side surface S15 being convex. The eighth lens E8 can have negative optical power, with its object-side surface S16 being convex and its image-side surface S17 being concave. The filter E9 can have an object-side surface S18 and an image-side surface S19. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the image plane IMA.

[0157] Table 3 shows the basic parameters of the optical system 200 of Embodiment 2, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0158] Table 3

[0159]

[0160] In this embodiment, the sign of the numerical value of the radius of curvature of each surface indicates only the direction of curvature. When the curvature directions of the lenses on optical axis I and optical axis II are the same, the signs of the numerical values ​​of the radii of curvature are opposite. Similarly, the sign of the numerical value of the thickness / distance of each surface indicates only the direction. The curvature direction of each surface and the thickness / distance of each surface can be found by referring to... Figure 5 and Figure 6 .

[0161] Among them, the on-axis distance W1 between the second element group G2 and the third element group G3, and the on-axis distance W2 between the third element group G3 and the filter E9 are variables that can change with the distance between the subject and the optical system 200.

[0162] When the subject is at infinity, the optical system 200 is in its first state. A structural diagram of the optical system 200 can be found here. Figure 5Wherein, W1 = -1.0671mm, W2 = -9.8559mm, the effective focal length (EFL) of the optical system 200 is 31.70mm, the maximum field of view (FOV) of the optical system 200 is 20.3122°, the aperture value (Fnox) of the optical system 200 in the first direction is 1.71, and the aperture value (Fnoy) of the optical system 200 in the second direction is 2.44. When the subject is at a predetermined distance from the optical system 200, the optical system 200 is in its second state. A structural diagram of the optical system 200 can be found here. Figure 6 .

[0163] In this embodiment, the object-side surface and image-side surface of any one of the lenses, from the first lens E1 to the eighth lens E8, are aspherical. Table 4 shows the conic coefficient K and higher-order coefficients A4, A6, A8, and A6 that can be used for the aspherical surfaces S1-S2 and S4-S17 in Embodiment 2. 10 A 12 A 14 A 16 A 18 and A 20 .

[0164] Table 4

[0165] S1 -26.287 -2.94E-01 -7.01E-02 -1.40E-02 -2.94E-03 -7.75E-04 -1.25E-04 -4.40E-05 -2.20E-05 -1.30E-05 S2 90.000 -1.65E-01 -5.69E-02 -1.03E-02 -2.04E-03 -4.82E-04 -4.70E-05 -2.10E-05 -1.80E-05 -6.00E-06 S4 -90.000 6.40E-02 3.60E-04 -1.53E-03 8.66E-04 -3.30E-04 -1.25E-04 3.20E-05 3.70E-05 1.00E-06 S5 90.000 -2.28E-02 4.24E-03 -1.65E-03 8.16E-04 -2.16E-04 -1.08E-04 6.00E-06 2.50E-05 -1.00E-06 S6 -90.000 -1.00E+00 2.12E-01 2.47E-02 1.51E-02 -1.58E-04 9.90E-05 -5.49E-04 -3.37E-08 -7.20E-05 S7 -0.027 -1.32E+00 3.22E-01 5.52E-03 7.55E-03 -4.44E-03 -1.26E-03 3.81E-04 1.62E-04 -1.18E-04 S8 0.056 3.27E+00 3.38E-02 3.44E-02 -5.21E-03 3.29E-03 -1.16E-03 1.31E-03 3.86E-04 -2.07E-04 S9 -2.447 1.64E+00 -1.88E-01 2.67E-02 -1.92E-02 5.31E-03 -1.20E-03 1.56E-03 -2.74E-04 -2.64E-04 S10 -90.000 3.95E-02 -1.67E-01 -2.80E-02 -1.27E-02 7.73E-04 2.00E-03 6.14E-04 -3.12E-04 -2.90E-04 S11 -0.549 -3.38E-01 -1.22E-01 -2.39E-02 -9.04E-03 -1.44E-03 1.23E-04 1.57E-04 -7.20E-05 6.10E-05 S12 -0.249 -3.13E+00 3.86E-01 -9.76E-02 2.01E-02 -6.25E-03 1.10E-03 -4.52E-04 -7.80E-05 4.00E-06 S13 -12.361 -2.07E+00 1.77E-01 -3.64E-02 5.98E-03 -1.12E-03 -1.14E-04 -1.08E-04 -1.08E-04 -3.80E-05 S14 -90.000 -1.60E-01 7.78E-02 2.55E-02 1.40E-02 3.73E-03 1.81E-03 4.05E-04 1.58E-04 2.40E-05 S15 7.032 1.39E-01 -1.93E-02 1.53E-02 -6.87E-03 -1.03E-03 -2.39E-04 -9.39E-04 5.75E-04 -5.40E-05 S16 -90.000 1.31E+00 -4.17E-01 2.01E-02 -2.65E-02 6.55E-03 8.14E-04 -2.97E-04 8.54E-04 -2.95E-04 S17 0.028 2.32E+00 -3.19E-01 5.61E-02 -2.39E-02 3.74E-03 -2.76E-03 -1.03E-04 -3.27E-04 -1.75E-04

[0166] Figure 7A The on-axis chromatic aberration curve of the optical system 200 in the first state of Embodiment 2 is shown, which represents the deflection of the focal point of light of different wavelengths after passing through the optical system 200. Figure 7B The astigmatism curve of the optical system 200 of Embodiment 2 in its first state is shown, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 7C The distortion curve of the optical system 200 of Embodiment 2 in its first state is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 7A , Figure 7B and Figure 7C It can be seen that the optical system 200 of Embodiment 2 can achieve good imaging quality in the first state.

[0167] Example 3

[0168] The following is for reference Figure 8 , Figure 9 , Figure 10A , Figure 10B and Figure 10C The optical system of Example 3 is described.

[0169] like Figure 8 and Figure 9As shown, the optical system 300 may include a first element group G1, a second element group G2, and a third element group G3 arranged sequentially from the object side to the image side. An image plane IMA may be provided on the image side, for example. The imageable object distance range of the optical system 300 can be from 10 cm to infinity. The magnification of the optical system 300 can be 5X.

[0170] The first element group G1 may include a first lens E1, a reflecting element P, and a second lens E2. The second element group G2 may include an aperture stop 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 disposed between the object side and the reflecting element P. The second lens E2, aperture stop STO, third lens E3, fourth lens E4, fifth lens E5, sixth lens E6, seventh lens E7, and eighth lens E8 are arranged sequentially along the optical axis II from the reflecting element P to the image side. In one example, a filter E9 may be disposed between the eighth lens E8 and the image plane IMA.

[0171] 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 subject moves from far to near the optical system 300, adjusting the distance between the third element group G3 and the second element group G2 on the optical axis II allows the optical system 300 to switch between a first state and a second state, thereby achieving the focusing function of the optical system 300. During the focusing process of the optical system 300, the maximum travel distance of the third element group G3 can be 6.3414 mm.

[0172] The first lens E1 can have positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being convex. The reflecting element P can have a reflecting surface S3, and the reflecting surface S3 is planar. The second lens E2 can have negative optical power, with its object-side surface S4 being concave and its image-side surface S5 being concave. The third lens E3 can have positive optical power, with its object-side surface S6 being convex and its image-side surface S7 being convex. The fourth lens E4 can have negative optical power, with its object-side surface S8 being convex and its image-side surface S9 being concave. The fifth lens E5 can have positive optical power, with its object-side surface S10 being convex and its image-side surface S11 being convex. The sixth lens E6 can have negative optical power, with its object-side surface S12 being concave and its image-side surface S13 being convex. The seventh lens E7 can have positive optical power, with its object-side surface S14 being convex and its image-side surface S15 being convex. The eighth lens E8 can have negative optical power, with its object-side surface S16 being convex and its image-side surface S17 being concave. The filter E9 can have an object-side surface S18 and an image-side surface S19. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the image plane IMA.

[0173] Table 5 shows the basic parameters of the optical system 300 of Embodiment 3, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0174] Table 5

[0175]

[0176] In this embodiment, the sign of the numerical value of the radius of curvature of each surface indicates only the direction of curvature. When the curvature directions of the lenses on optical axis I and optical axis II are the same, the signs of the numerical values ​​of the radii of curvature are opposite. Similarly, the sign of the numerical value of the thickness / distance of each surface indicates only the direction. The curvature direction of each surface and the thickness / distance of each surface can be found by referring to... Figure 8 and Figure 9 .

[0177] Among them, the on-axis distance W1 between the second element group G2 and the third element group G3, and the on-axis distance W2 between the third element group G3 and the filter E9 are variables that can change with the distance between the subject and the optical system 300.

[0178] When the subject is at infinity, the optical system 300 is in its first state. A structural diagram of the optical system 300 can be found here. Figure 8 Wherein, W1 = -1.1220mm, W2 = -10.7125mm, the effective focal length (EFL) of the optical system 300 is 31.70mm, the maximum field of view (FOV) of the optical system 300 is 20.3122°, the aperture value (Fnox) of the optical system 300 in the first direction is 2.34, and the aperture value (Fnoy) of the optical system 300 in the second direction is 3.35. When the subject is at a predetermined distance from the optical system 300, the optical system 300 is in its second state. A structural diagram of the optical system 300 can be found here. Figure 9 .

[0179] In this embodiment, the object-side surface and image-side surface of any one of the lenses, from the first lens E1 to the eighth lens E8, are aspherical. Table 6 shows the conic coefficient K and higher-order coefficients A4, A6, A8, and A6 that can be used for the aspherical surfaces S1-S2 and S4-S17 in Embodiment 3. 10 A 12 A 14 A 16 A 18 and A 20 .

[0180] Table 6

[0181] S1 -52.355 -5.20E-02 -1.03E-02 -1.12E-03 -2.90E-04 -9.80E-05 -1.30E-05 -8.00E-06 6.00E-06 -3.61E-08 S2 90.000 -6.18E-02 -7.99E-03 -1.14E-03 -2.88E-04 -9.30E-05 -1.10E-05 -5.00E-06 6.00E-06 -1.00E-06 S4 -90.000 3.64E-02 2.36E-04 -3.01E-04 9.00E-06 6.80E-05 -3.10E-05 3.51E-07 4.00E-06 -3.00E-06 S5 -52.916 -8.86E-03 1.30E-03 -3.53E-04 4.20E-05 4.90E-05 -3.90E-05 1.00E-06 1.00E-06 -1.00E-06 S6 -90.000 -4.06E-01 6.00E-02 -2.93E-03 3.29E-03 -4.16E-04 2.51E-04 -2.10E-05 -6.00E-06 4.00E-06 S7 0.274 -7.44E-01 1.06E-01 -8.77E-03 6.05E-03 -1.23E-03 5.71E-04 -1.83E-04 1.70E-05 2.00E-06 S8 0.057 1.62E+00 -5.64E-02 1.81E-02 -2.18E-03 1.40E-03 -3.40E-04 -1.20E-04 3.00E-05 -1.10E-05 S9 -2.336 9.48E-01 -9.59E-02 3.00E-02 -1.15E-02 3.95E-03 -2.02E-03 3.48E-04 3.20E-05 -5.00E-06 S10 -79.556 -9.55E-02 -2.18E-02 -1.38E-02 -9.45E-03 7.00E-06 -6.49E-04 -8.10E-05 1.81E-04 -2.10E-05 S11 -0.293 -7.20E-02 -4.99E-02 -1.71E-02 -7.05E-03 -1.53E-03 -5.16E-04 -1.07E-04 -1.00E-06 -1.40E-05 S12 -0.041 -2.42E+00 2.94E-01 -6.46E-02 1.44E-02 -3.06E-03 4.67E-04 -1.01E-04 -1.10E-05 8.00E-06 S13 -9.564 -2.05E+00 2.02E-01 -4.47E-02 7.30E-03 -5.89E-04 -9.00E-05 -5.40E-05 -4.10E-05 -1.10E-05 S14 -90.000 -1.61E-01 1.02E-01 1.60E-03 5.27E-03 8.60E-05 2.34E-04 -2.10E-04 -8.00E-06 -2.60E-05 S15 -0.491 -2.58E-02 4.68E-02 7.07E-04 -5.76E-03 1.57E-03 -2.30E-03 2.40E-04 2.38E-04 -6.00E-05 S16 -90.000 9.49E-01 -3.49E-01 3.37E-02 -2.05E-02 7.24E-03 -2.99E-03 1.43E-03 2.10E-04 -2.21E-04 S17 0.095 2.09E+00 -2.27E-01 5.97E-02 -1.59E-02 4.01E-03 -1.68E-03 3.84E-04 -1.15E-04 -9.00E-06

[0182] Figure 10AThe on-axis chromatic aberration curve of the optical system 300 of Embodiment 3 is shown in the first state, which represents the deflection of the focal point of light of different wavelengths after passing through the optical system 300. Figure 10B The astigmatism curve of the optical system 300 of Embodiment 3 in its first state is shown, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 10C The distortion curve of the optical system 300 in the first state of Embodiment 3 is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 10A , Figure 10B and Figure 10C It can be seen that the optical system 300 of Embodiment 3 can achieve good imaging quality in the first state.

[0183] Example 4

[0184] The following is for reference Figure 11 , Figure 12 , Figure 13A , Figure 13B and Figure 13C The optical system of Example 4 is described.

[0185] like Figure 11 and Figure 12 As shown, the optical system 400 may include a first element group G1, a second element group G2, and a third element group G3 arranged sequentially from the object side to the image side. An image plane IMA may be provided on the image side, for example. The imageable object distance range of the optical system 400 can be from 10 cm to infinity. The magnification of the optical system 400 can be 5X.

[0186] The first element group G1 may include a first lens E1, a reflecting element P, and a second lens E2. The second element group G2 may include an aperture stop 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 disposed between the object side and the reflecting element P. The second lens E2, aperture stop STO, third lens E3, fourth lens E4, fifth lens E5, sixth lens E6, seventh lens E7, and eighth lens E8 are arranged sequentially along the optical axis II from the reflecting element P to the image side. In one example, a filter E9 may be disposed between the eighth lens E8 and the image plane IMA.

[0187] 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 subject moves from far to near the optical system 400, adjusting the distance between the third element group G3 and the second element group G2 on the optical axis II allows the optical system 400 to switch between a first state and a second state, thereby enabling the focusing function of the optical system 400. During the focusing process of the optical system 400, the maximum travel distance of the third element group G3 can be 6.6345mm.

[0188] The first lens E1 can have positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being convex. The reflecting element P can have a reflecting surface S3, and the reflecting surface S3 is planar. The second lens E2 can have negative optical power, with its object-side surface S4 being concave and its image-side surface S5 being concave. The third lens E3 can have positive optical power, with its object-side surface S6 being convex and its image-side surface S7 being convex. The fourth lens E4 can have negative optical power, with its object-side surface S8 being convex and its image-side surface S9 being concave. The fifth lens E5 can have positive optical power, with its object-side surface S10 being convex and its image-side surface S11 being convex. The sixth lens E6 can have negative optical power, with its object-side surface S12 being concave and its image-side surface S13 being convex. The seventh lens E7 can have positive optical power, with its object-side surface S14 being convex and its image-side surface S15 being convex. The eighth lens E8 can have negative optical power, with its object-side surface S16 being convex and its image-side surface S17 being concave. The filter E9 can have an object-side surface S18 and an image-side surface S19. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the image plane IMA.

[0189] Table 7 shows the basic parameters of the optical system 400 of Embodiment 4, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0190] Table 7

[0191]

[0192] In this embodiment, the sign of the numerical value of the radius of curvature of each surface indicates only the direction of curvature. When the curvature directions of the lenses on optical axis I and optical axis II are the same, the signs of the numerical values ​​of the radii of curvature are opposite. Similarly, the sign of the numerical value of the thickness / distance of each surface indicates only the direction. The curvature direction of each surface and the thickness / distance of each surface can be found by referring to... Figure 11 and Figure 12 .

[0193] Among them, the on-axis distance W1 between the second element group G2 and the third element group G3, and the on-axis distance W2 between the third element group G3 and the filter E9 are variables that can change with the distance between the subject and the optical system 400.

[0194] When the subject is at infinity, the optical system 400 is in its first state. A structural diagram of the optical system 400 can be found here. Figure 11 Wherein, W1 = -1.2040mm, W2 = -11.2879mm, the effective focal length (EFL) of the optical system 400 is 31.70mm, the maximum field of view (FOV) of the optical system 400 is 20.3122°, the aperture value (Fnox) of the optical system 400 in the first direction is 3.00, and the aperture value (Fnoy) of the optical system 400 in the second direction is 4.25. When the subject is at a predetermined distance from the optical system 400, the optical system 400 is in its second state. A structural diagram of the optical system 400 can be found here. Figure 12 .

[0195] In this embodiment, the object-side surface and image-side surface of any one of the lenses, from the first lens E1 to the eighth lens E8, are aspherical. Table 8 shows the conic coefficient K and higher-order coefficients A4, A6, A8, and A6 that can be used for the aspherical surfaces S1-S2 and S4-S17 in Embodiment 4. 10 A 12 A 14 A 16 A 18 and A 20 .

[0196] Table 8

[0197] S1 -60.821 -1.53E-02 -1.26E-03 -6.50E-05 1.10E-05 -1.10E-05 -2.00E-06 -1.28E-07 1.00E-06 1.00E-06 S2 90.000 -2.08E-02 -4.24E-04 -9.70E-05 1.30E-05 -1.10E-05 -2.00E-06 1.00E-06 1.37E-08 1.00E-06 S4 -90.000 1.04E-02 -2.78E-04 1.69E-04 -8.10E-05 2.40E-05 -1.10E-05 -2.00E-06 -1.00E-06 2.00E-06 S5 -45.563 -8.93E-03 1.46E-04 1.14E-04 -7.50E-05 1.50E-05 -1.10E-05 1.00E-06 -1.00E-06 4.00E-06 S6 -90.000 -2.10E-01 2.26E-02 -2.69E-03 8.69E-04 -2.38E-04 6.30E-05 9.00E-06 -5.00E-06 1.00E-06 S7 0.269 -4.39E-01 4.77E-02 -6.79E-03 2.33E-03 -7.78E-04 4.32E-04 -6.10E-05 -1.70E-05 2.00E-06 S8 0.040 9.31E-01 -4.03E-02 8.34E-03 -1.57E-03 5.76E-04 9.10E-05 -1.64E-04 -6.90E-05 -2.00E-06 S9 -2.354 6.03E-01 -6.48E-02 2.05E-02 -6.49E-03 2.80E-03 -1.14E-03 -4.90E-05 -3.80E-05 2.10E-05 S10 -67.816 -6.96E-02 -1.13E-02 1.41E-03 -3.44E-03 1.22E-03 -5.53E-04 -1.72E-04 4.60E-05 -1.70E-05 S11 -0.503 -3.76E-02 -2.15E-02 -4.91E-03 -1.83E-03 4.90E-05 -3.20E-05 6.80E-05 5.70E-05 -2.00E-06 S12 -0.042 -1.84E+00 2.14E-01 -4.06E-02 8.49E-03 -1.28E-03 -1.06E-04 -3.00E-05 -7.00E-05 -1.00E-06 S13 -9.193 -1.65E+00 1.62E-01 -3.04E-02 4.98E-03 3.88E-04 -2.62E-04 -2.50E-05 -7.70E-05 -2.50E-05 S14 -90.000 -1.72E-01 7.76E-02 -3.81E-03 3.83E-03 8.21E-04 3.20E-04 -6.10E-05 -2.40E-05 -2.90E-05 S15 -0.604 -4.25E-02 3.87E-02 1.35E-03 -2.68E-03 2.58E-03 -1.85E-03 3.20E-05 -5.50E-05 -6.00E-06 S16 -90.000 8.46E-01 -2.50E-01 3.09E-02 -1.43E-02 4.38E-03 -2.63E-03 4.94E-04 4.50E-05 -1.50E-05 S17 0.069 1.83E+00 -1.78E-01 4.91E-02 -1.11E-02 2.86E-03 -9.49E-04 2.05E-04 -4.30E-05 -1.10E-05

[0198] Figure 13A The on-axis chromatic aberration curve of the optical system 400 in the first state of Embodiment 4 is shown, which represents the deflection of the focal point of light of different wavelengths after passing through the optical system 400. Figure 13B The astigmatism curve of the optical system 400 of Embodiment 4 in its first state is shown, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 13C The distortion curve of the optical system 400 in the first state of Embodiment 4 is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 13A , Figure 13B and Figure 13C It can be seen that the optical system 400 of Embodiment 4 can achieve good imaging quality in the first state.

[0199] Example 5

[0200] The following is for reference Figure 14 , Figure 15 , Figure 16A , Figure 16B and Figure 16C The optical system of Example 5 is described.

[0201] like Figure 14 and Figure 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 sequentially from the object side to the image side. An image plane IMA may be provided on the image side, for example. The imageable object distance range of the optical system 500 can be from 17 cm to infinity. The magnification of the optical system 500 can be 2.5X.

[0202] The first element group G1 may include a first lens E1, a reflecting element P, and a second lens E2. The second element group G2 may include an aperture stop 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 disposed between the object side and the reflecting element P. The second lens E2, aperture stop STO, third lens E3, fourth lens E4, fifth lens E5, sixth lens E6, seventh lens E7, and eighth lens E8 are arranged sequentially along the optical axis II from the reflecting element P to the image side. In one example, a filter E9 may be disposed between the eighth lens E8 and the image plane IMA.

[0203] 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 subject moves from far to near the optical system 500, adjusting the distance between the third element group G3 and the second element group G2 on the optical axis II allows the optical system 500 to switch between a first state and a second state, thereby enabling the focusing function of the optical system 500. During the focusing process of the optical system 500, the maximum travel distance of the third element group G3 can be 1.0087 mm.

[0204] The first lens E1 can have positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The reflecting element P can have a reflecting surface S3, and the reflecting surface S3 is planar. The second lens E2 can have negative optical power, with its object-side surface S4 being convex and its image-side surface S5 being concave. The third lens E3 can have positive optical power, with its object-side surface S6 being convex and its image-side surface S7 being convex. The fourth lens E4 can have negative optical power, with its object-side surface S8 being convex and its image-side surface S9 being concave. The fifth lens E5 can have positive optical power, with its object-side surface S10 being convex and its image-side surface S11 being convex. The sixth lens E6 can have positive optical power, with its object-side surface S12 being concave and its image-side surface S13 being convex. The seventh lens E7 can have positive optical power, with its object-side surface S14 being concave and its image-side surface S15 being convex. The eighth lens E8 can have negative optical power, with its object-side surface S16 being convex and its image-side surface S17 being concave. The filter E9 can have an object-side surface S18 and an image-side surface S19. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the image plane IMA.

[0205] Table 9 shows the basic parameters of the optical system 500 of Embodiment 5, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0206] Table 9

[0207]

[0208]

[0209] In this embodiment, the sign of the numerical value of the radius of curvature of each surface indicates only the direction of curvature. When the curvature directions of the lenses on optical axis I and optical axis II are the same, the signs of the numerical values ​​of the radii of curvature are opposite. Similarly, the sign of the numerical value of the thickness / distance of each surface indicates only the direction. The curvature direction of each surface and the thickness / distance of each surface can be found by referring to... Figure 14 and Figure 15 .

[0210] Among them, the on-axis distance W1 between the second element group G2 and the third element group G3, and the on-axis distance W2 between the third element group G3 and the filter E9 are variables that can change with the distance between the subject and the optical system 500.

[0211] When the subject is at infinity, the optical system 500 is in its first state. A structural diagram of the optical system 500 can be found here. Figure 14Wherein, W1 = -1.0343mm, W2 = -4.5275mm, the effective focal length (EFL) of optical system 500 is 15.19mm, the maximum field of view (FOV) of optical system 500 is 41.72°, the aperture value (Fnox) of optical system 500 in the first direction is 3.3, and the aperture value (Fnoy) of optical system 500 in the second direction is 3.3. When the subject is at a predetermined distance from optical system 500, optical system 500 is in its second state. A structural diagram of optical system 500 can be found here. Figure 15 .

[0212] In this embodiment, the object-side surface and image-side surface of any one of the lenses, from the first lens E1 to the eighth lens E8, are aspherical. Table 10 shows the conic coefficient K and higher-order coefficients A4, A6, A8, and A6 that can be used for the aspherical surfaces S1-S2 and S4-S17 in Embodiment 5. 10 A 12 A 14 A 16 A 18 and A 20 .

[0213] Table 10

[0214] S1 -20.959 -3.26E-02 -4.33E-03 3.14E-04 -3.20E-05 -9.00E-06 1.00E-06 4.00E-06 2.00E-06 -2.00E-06 S2 90.000 -7.72E-02 -2.76E-03 2.10E-04 -4.50E-05 -4.00E-06 1.00E-06 5.00E-06 -1.43E-07 -3.00E-06 S4 -90.000 -9.61E-03 5.02E-03 -9.96E-04 1.82E-04 -1.50E-05 1.50E-05 -7.00E-06 1.00E-06 -1.00E-06 S5 -42.424 -1.27E-02 3.52E-03 -6.17E-04 9.20E-05 -8.00E-06 1.20E-05 -5.00E-06 2.00E-06 2.61E-07 S6 -90.000 -5.32E-02 3.22E-03 -2.17E-04 9.60E-05 -3.30E-05 1.20E-05 -4.07E-09 2.00E-06 1.00E-06 S7 0.592 -1.20E-01 9.31E-03 -1.97E-04 -1.09E-04 5.90E-05 -8.00E-06 1.80E-05 -8.00E-06 7.00E-06 S8 0.052 2.93E-01 -1.04E-02 2.94E-03 -7.22E-04 1.21E-04 -1.50E-05 1.70E-05 -7.00E-06 7.00E-06 S9 -2.343 1.96E-01 -1.75E-02 4.01E-03 -9.31E-04 1.39E-04 -1.50E-05 7.00E-06 -8.94E-08 2.00E-06 S10 -90.000 -4.06E-02 4.55E-04 4.03E-04 -6.50E-05 -5.40E-05 -1.20E-05 2.00E-06 1.00E-06 2.00E-06 S11 -0.537 -3.32E-02 -2.19E-03 1.02E-04 -1.60E-05 -3.90E-05 -3.10E-05 1.00E-06 -2.00E-06 2.00E-06 S12 0.100 -1.24E+00 1.08E-01 -2.26E-02 5.56E-03 -1.24E-03 1.24E-04 7.20E-05 -4.60E-05 9.00E-06 S13 -0.248 -1.41E+00 1.48E-01 -3.23E-02 9.64E-03 -2.26E-03 1.76E-04 1.50E-05 1.80E-05 -7.00E-06 S14 -90.000 -1.37E-01 1.08E-02 -1.48E-02 4.18E-03 -1.94E-03 5.40E-05 -1.97E-04 1.12E-04 1.00E-05 S15 -1.064 -8.92E-03 -1.19E-02 -3.87E-03 -1.01E-03 -8.99E-04 -7.17E-04 -6.09E-04 -5.70E-05 9.00E-06 S16 -90.000 1.10E+00 -1.07E-01 2.87E-02 -4.69E-03 1.97E-03 -5.40E-04 -6.16E-04 -1.02E-04 -2.20E-05 S17 0.014 2.76E+00 -2.14E-01 1.03E-01 -1.57E-02 9.97E-03 -2.03E-03 1.18E-03 -1.13E-04 8.10E-05

[0215] Figure 16A The on-axis chromatic aberration curve of the optical system 500 in the first state of Embodiment 5 is shown, which represents the deflection of the focal point of light of different wavelengths after passing through the optical system 500. Figure 16B The astigmatism curve of the optical system 500 of Embodiment 5 is shown in the first state, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 16C The distortion curve of the optical system 500 of Embodiment 5 in its first state is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 16A , Figure 16B and Figure 16C It can be seen that the optical system 500 of Embodiment 5 can achieve good imaging quality in the first state.

[0216] Example 6

[0217] The following is for reference Figure 17 , Figure 18 , Figure 19A , Figure 19B and Figure 19C The optical system of Example 6 is described.

[0218] like Figure 17 and Figure 18As shown, the optical system 600 may include a first element group G1, a second element group G2, and a third element group G3 arranged sequentially from the object side to the image side. An image plane IMA may be provided on the image side, for example. The imageable object distance range of the optical system 600 can be from 10 cm to infinity. The magnification of the optical system 600 can be 5X.

[0219] The first element group G1 may include a first lens E1, a reflecting element P, and a second lens E2. The second element group G2 may include an aperture stop 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 disposed between the object side and the reflecting element P. The second lens E2, aperture stop STO, third lens E3, fourth lens E4, fifth lens E5, sixth lens E6, seventh lens E7, and eighth lens E8 are arranged sequentially along the optical axis II from the reflecting element P to the image side. In one example, a filter E9 may be disposed between the eighth lens E8 and the image plane IMA.

[0220] 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 subject moves closer to the optical system 600, adjusting the distance between the third element group G3 and the second element group G2 on the optical axis II allows the optical system 600 to switch between a first state and a second state, thereby enabling the focusing function of the optical system 600. During the focusing process of the optical system 600, the maximum travel distance of the third element group G3 can be 5.8859 mm.

[0221] The first lens E1 can have positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being convex. The reflecting element P can have a reflecting surface S3, and the reflecting surface S3 is planar. The second lens E2 can have negative optical power, with its object-side surface S4 being concave and its image-side surface S5 being concave. The third lens E3 can have positive optical power, with its object-side surface S6 being convex and its image-side surface S7 being convex. The fourth lens E4 can have negative optical power, with its object-side surface S8 being convex and its image-side surface S9 being concave. The fifth lens E5 can have positive optical power, with its object-side surface S10 being convex and its image-side surface S11 being convex. The sixth lens E6 can have negative optical power, with its object-side surface S12 being concave and its image-side surface S13 being convex. The seventh lens E7 can have positive optical power, with its object-side surface S14 being concave and its image-side surface S15 being convex. The eighth lens E8 can have negative optical power, with its object-side surface S16 being convex and its image-side surface S17 being concave. The filter E9 can have an object-side surface S18 and an image-side surface S19. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the image plane IMA.

[0222] Table 11 shows the basic parameters of the optical system 600 of Embodiment 6, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0223] Table 11

[0224]

[0225]

[0226] In this embodiment, the sign of the numerical value of the radius of curvature of each surface indicates only the direction of curvature. When the curvature directions of the lenses on optical axis I and optical axis II are the same, the signs of the numerical values ​​of the radii of curvature are opposite. Similarly, the sign of the numerical value of the thickness / distance of each surface indicates only the direction. The curvature direction of each surface and the thickness / distance of each surface can be found by referring to... Figure 17 and Figure 18 .

[0227] Among them, the on-axis distance W1 between the second element group G2 and the third element group G3, and the on-axis distance W2 between the third element group G3 and the filter E9 are variables that can change with the distance between the subject and the optical system 600.

[0228] When the subject is at infinity, the optical system 600 is in its first state. A structural diagram of the optical system 600 can be found here. Figure 17 Wherein, W1 = -1.1538mm, W2 = -9.4875mm, the effective focal length (EFL) of the optical system 600 is 31.68mm, the maximum field of view (FOV) of the optical system 600 is 20.3122°, the aperture value (Fnox) of the optical system 600 in the first direction is 1.9, and the aperture value (Fnoy) of the optical system 600 in the second direction is 1.9. When the subject is at a predetermined distance from the optical system 600, the optical system 600 is in its second state. A structural diagram of the optical system 600 can be found here. Figure 18 .

[0229] In this embodiment, the object-side surface and image-side surface of any one of the lenses, from the first lens E1 to the eighth lens E8, are aspherical. Table 12 shows the conic coefficient K and higher-order coefficients A4, A6, A8, and A6 that can be used for the aspherical surfaces S1-S2 and S4-S17 in Embodiment 6. 10 A 12 A 14 A 16 A 18 and A 20 .

[0230] Table 12

[0231] S1 -47.710 -1.89E-01 -5.01E-02 -7.65E-03 -1.57E-03 -3.32E-04 -5.10E-05 -1.00E-05 -5.00E-06 -1.00E-06 S2 90.000 -3.35E-01 -7.46E-02 -1.44E-02 -3.21E-03 -7.14E-04 -1.41E-04 -4.30E-05 -1.60E-05 1.66E-09 S4 -90.000 8.68E-02 -1.24E-03 -1.04E-03 2.04E-04 8.00E-05 4.00E-06 -3.10E-05 8.00E-06 -4.00E-06 S5 -90.000 -1.02E-02 3.25E-03 -1.47E-03 3.10E-04 6.30E-05 -1.80E-05 -3.90E-05 1.00E-05 -8.00E-06 S6 -90.000 -5.75E-01 1.14E-01 5.91E-03 9.19E-03 1.04E-04 6.80E-05 -3.20E-04 9.20E-05 -2.60E-05 S7 0.231 -1.01E+00 1.73E-01 -3.87E-03 9.57E-03 -1.23E-03 -1.34E-03 1.39E-04 1.94E-04 -5.40E-05 S8 0.046 1.93E+00 -4.42E-02 2.31E-02 -3.42E-03 2.19E-03 -1.71E-03 -7.10E-05 2.34E-04 -4.20E-05 S9 -2.380 9.52E-01 -9.23E-02 2.61E-02 -8.62E-03 3.39E-03 -1.38E-03 1.32E-04 8.70E-05 -2.70E-05 S10 -73.513 -8.37E-02 -1.55E-02 -9.69E-03 -4.16E-03 3.60E-05 -1.40E-05 -2.13E-04 1.90E-05 5.00E-06 S11 -0.431 -8.62E-02 -3.83E-02 -1.12E-02 -4.44E-03 -8.09E-04 -1.97E-04 -1.38E-04 -3.80E-05 1.00E-06 S12 -0.095 -2.92E+00 3.43E-01 -8.22E-02 1.91E-02 -3.78E-03 1.06E-03 -7.20E-05 1.00E-06 -9.00E-06 S13 -10.994 -2.06E+00 1.71E-01 -4.46E-02 3.99E-03 -6.20E-04 1.80E-05 9.60E-05 6.90E-05 1.40E-05 S14 -90.000 -1.39E-01 7.92E-02 2.78E-03 4.25E-03 1.27E-04 2.89E-04 -8.50E-05 3.60E-05 2.00E-06 S15 0.009 -4.31E-03 2.91E-02 -4.55E-04 -8.06E-03 8.20E-04 -1.20E-03 -3.19E-04 2.63E-04 -7.30E-05 S16 -90.000 1.12E+00 -3.76E-01 1.90E-02 -2.32E-02 7.74E-03 -1.11E-03 5.03E-04 4.61E-04 -2.43E-04 S17 0.018 2.24E+00 -2.56E-01 5.67E-02 -1.74E-02 3.70E-03 -1.71E-03 1.44E-04 -7.00E-05 -2.80E-05

[0232] Figure 19A The on-axis chromatic aberration curve of the optical system 600 of Embodiment 6 is shown in the first state, which represents the deflection of the focal point of light of different wavelengths after passing through the optical system 600. Figure 19B The astigmatism curve of the optical system 600 of Embodiment 6 is shown in the first state, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 19C The distortion curve of the optical system 600 of Embodiment 6 in its first state is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 19A , Figure 19B and Figure 19C It can be seen that the optical system 600 of Embodiment 6 can achieve good imaging quality in the first state.

[0233] Example 7

[0234] The following is for reference Figure 20 , Figure 21 , Figure 22A , Figure 22B and Figure 22C The optical system of Example 7 is described.

[0235] like Figure 20 and Figure 21 As shown, the optical system 700 may include a first element group G1, a second element group G2, and a third element group G3 arranged sequentially from the object side to the image side. An image plane IMA may be provided on the image side, for example. The imageable object distance range of the optical system 700 can be from 10 cm to infinity. The magnification of the optical system 700 can be 5X.

[0236] The first element group G1 may include a first lens E1, a reflecting element P, and a second lens E2. The second element group G2 may include an aperture stop 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 disposed between the object side and the reflecting element P. The second lens E2, aperture stop STO, third lens E3, fourth lens E4, fifth lens E5, sixth lens E6, seventh lens E7, and eighth lens E8 are arranged sequentially along the optical axis II from the reflecting element P to the image side. In one example, a filter E9 may be disposed between the eighth lens E8 and the image plane IMA.

[0237] 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 subject moves from far to near the optical system 700, adjusting the distance between the third element group G3 and the second element group G2 on the optical axis II allows the optical system 700 to switch between a first state and a second state, thereby enabling the focusing function of the optical system 700. During the focusing process of the optical system 700, the maximum travel distance of the third element group G3 can be 5.5307 mm.

[0238] The first lens E1 can have positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being convex. The reflecting element P can have a reflecting surface S3, and the reflecting surface S3 is planar. The second lens E2 can have negative optical power, with its object-side surface S4 being concave and its image-side surface S5 being concave. The third lens E3 can have positive optical power, with its object-side surface S6 being convex and its image-side surface S7 being convex. The fourth lens E4 can have negative optical power, with its object-side surface S8 being convex and its image-side surface S9 being concave. The fifth lens E5 can have positive optical power, with its object-side surface S10 being convex and its image-side surface S11 being convex. The sixth lens E6 can have negative optical power, with its object-side surface S12 being concave and its image-side surface S13 being convex. The seventh lens E7 can have positive optical power, with its object-side surface S14 being convex and its image-side surface S15 being convex. The eighth lens E8 can have negative optical power, with its object-side surface S16 being convex and its image-side surface S17 being concave. The filter E9 can have an object-side surface S18 and an image-side surface S19. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the image plane IMA.

[0239] Table 13 shows the basic parameters of the optical system 700 of Embodiment 7, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0240] Table 13

[0241]

[0242]

[0243] In this embodiment, the sign of the numerical value of the radius of curvature of each surface indicates only the direction of curvature. When the curvature directions of the lenses on optical axis I and optical axis II are the same, the signs of the numerical values ​​of the radii of curvature are opposite. Similarly, the sign of the numerical value of the thickness / distance of each surface indicates only the direction. The curvature direction of each surface and the thickness / distance of each surface can be found by referring to... Figure 20 and Figure 21 .

[0244] Among them, the on-axis distance W1 between the second element group G2 and the third element group G3, and the on-axis distance W2 between the third element group G3 and the filter E9 are variables that can change with the distance between the subject and the optical system 700.

[0245] When the subject is at infinity, the optical system 700 is in its first state. A structural diagram of the optical system 700 can be found here. Figure 20 Wherein, W1 = -1.2789mm, W2 = -11.1713mm, the effective focal length (EFL) of optical system 700 is 31.70mm, the maximum field of view (FOV) of optical system 700 is 20.3122°, the aperture value (Fnox) of optical system 700 in the first direction is 3.3, and the aperture value (Fnoy) of optical system 700 in the second direction is 3.3. When the subject is a predetermined distance from optical system 700, optical system 700 is in its second state. A structural diagram of optical system 700 can be found here. Figure 21 .

[0246] In this embodiment, the object-side surface and image-side surface of any one of the lenses, from the first lens E1 to the eighth lens E8, are aspherical. Table 14 shows the conic coefficient K and higher-order coefficients A4, A6, A8, and A6 that can be used for the aspherical surfaces S1-S2 and S4-S17 in Embodiment 7. 10 A 12 A 14 A 16 A 18 and A 20 .

[0247] Table 14

[0248]

[0249]

[0250] Figure 22A The on-axis chromatic aberration curve of the optical system 700 of Embodiment 7 is shown in the first state, which represents the deflection of the focal point of light of different wavelengths after passing through the optical system 700. Figure 22B The astigmatism curve of the optical system 700 of Embodiment 7 is shown in the first state, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 22C The distortion curve of the optical system 700 of Embodiment 7 in its first state is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 22A , Figure 22B and Figure 22C It can be seen that the optical system 700 of Embodiment 7 can achieve good imaging quality in the first state.

[0251] Example 8

[0252] The following is for reference Figure 23 , Figure 24 , Figure 25A , Figure 25B and Figure 25C The optical system of Example 8 is described.

[0253] like Figure 23 and Figure 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 sequentially from the object side to the image side. An image plane IMA may be provided on the image side, for example. The imageable object distance range of the optical system 800 can be from 10 cm to infinity. The magnification of the optical system 800 can be 8X.

[0254] The first element group G1 may include a first lens E1, a reflecting element P, and a second lens E2. The second element group G2 may include an aperture stop 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 disposed between the object side and the reflecting element P. The second lens E2, aperture stop STO, third lens E3, fourth lens E4, fifth lens E5, sixth lens E6, seventh lens E7, and eighth lens E8 are arranged sequentially along the optical axis II from the reflecting element P to the image side. In one example, a filter E9 may be disposed 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 subject moves from far to near the optical system 800, adjusting the distance between the third element group G3 and the second element group G2 on the optical axis II allows the optical system 800 to switch between a first state and a second state, thereby enabling the focusing function of the optical system 800. During the focusing process of the optical system 800, the maximum travel distance of the third element group G3 can be 3.5912 mm.

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

[0257] Table 15 shows the basic parameters of the optical system 800 of Embodiment 8, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0258] Table 15

[0259]

[0260] In this embodiment, the sign of the numerical value of the radius of curvature of each surface indicates only the direction of curvature. When the curvature directions of the lenses on optical axis I and optical axis II are the same, the signs of the numerical values ​​of the radii of curvature are opposite. Similarly, the sign of the numerical value of the thickness / distance of each surface indicates only the direction. The curvature direction of each surface and the thickness / distance of each surface can be found by referring to... Figure 23 and Figure 24 .

[0261] Among them, the on-axis distance W1 between the second element group G2 and the third element group G3, and the on-axis distance W2 between the third element group G3 and the filter E9 are variables that can change with the distance between the subject and the optical system 800.

[0262] When the subject is at infinity, the optical system 800 is in its first state. A structural diagram of the optical system 800 can be found here. Figure 23Wherein, W1 = -1.3070mm, W2 = -6.9702mm, the effective focal length (EFL) of optical system 800 is 27.73mm, the maximum field of view (FOV) of optical system 800 is 12.3122°, the aperture value (Fnox) of optical system 800 in the first direction is 2.591, and the aperture value (Fnoy) of optical system 800 in the second direction is 2.591. When the subject is at a predetermined distance from optical system 800, optical system 800 is in its second state. A structural diagram of optical system 800 can be found here. Figure 24 .

[0263] In this embodiment, the object-side surface and image-side surface of any one of the lenses, from the first lens E1 to the eighth lens E8, are aspherical. Table 16 shows the conic coefficient K and higher-order coefficients A4, A6, A8, and A6 that can be used for the aspherical surfaces S1-S2 and S4-S17 in Embodiment 8. 10 A 12 A 14 A 16 A 18 and A 20 .

[0264] Table 16

[0265]

[0266]

[0267] Figure 25A The on-axis chromatic aberration curve of the optical system 800 in the first state of Embodiment 8 is shown, which represents the deflection of the focal point of light of different wavelengths after passing through the optical system 800. Figure 25B The astigmatism curve of the optical system 800 of Embodiment 8 is shown in the first state, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 25C The distortion curve of the optical system 800 of Embodiment 8 in its first state is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 25A , Figure 25B and Figure 25C It can be seen that the optical system 800 of Embodiment 8 can achieve good imaging quality in the first state.

[0268] Example 9

[0269] The following is for reference Figure 26 , Figure 27 , Figure 28A , Figure 28B and Figure 28C The optical system of Example 9 is described.

[0270] like Figure 26 and Figure 27As shown, the optical system 900 may include a first element group G1, a second element group G2, and a third element group G3 arranged sequentially from the object side to the image side. An image plane IMA may be provided on the image side, for example. The imageable object distance range of the optical system 900 can be from 10 cm to infinity. The magnification of the optical system 900 can be 8X.

[0271] The first element group G1 may include a first lens E1, a reflecting element P, and a second lens E2. The second element group G2 may include an aperture stop 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 disposed between the object side and the reflecting element P. The second lens E2, aperture stop STO, third lens E3, fourth lens E4, fifth lens E5, sixth lens E6, seventh lens E7, and eighth lens E8 are arranged sequentially along the optical axis II from the reflecting element P to the image side. In one example, a filter E9 may be disposed between the eighth lens E8 and the image plane IMA.

[0272] 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 subject moves from far to near the optical system 900, adjusting the distance between the third element group G3 and the second element group G2 on the optical axis II allows the optical system 900 to switch between a first state and a second state, thereby enabling the focusing function of the optical system 900. During the focusing process of the optical system 900, the maximum travel distance of the third element group G3 can be 3.5362 mm.

[0273] The first lens E1 can have positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being convex. The reflecting element P can have a reflecting surface S3, and the reflecting surface S3 is planar. The second lens E2 can have negative optical power, with its object-side surface S4 being concave and its image-side surface S5 being concave. The third lens E3 can have positive optical power, with its object-side surface S6 being convex and its image-side surface S7 being convex. The fourth lens E4 can have negative optical power, with its object-side surface S8 being convex and its image-side surface S9 being concave. The fifth lens E5 can have positive optical power, with its object-side surface S10 being convex and its image-side surface S11 being convex. The sixth lens E6 can have negative optical power, with its object-side surface S12 being concave and its image-side surface S13 being convex. The seventh lens E7 can have positive optical power, with its object-side surface S14 being concave and its image-side surface S15 being convex. The eighth lens E8 can have negative optical power, with its object-side surface S16 being concave and its image-side surface S17 being convex. The filter E9 can have an object-side surface S18 and an image-side surface S19. Light from the object passes sequentially through each surface S1 to S19 and is finally imaged on the image plane IMA.

[0274] Table 17 shows the basic parameters of the optical system 900 of Embodiment 9, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0275] Table 17

[0276]

[0277] In this embodiment, the sign of the numerical value of the radius of curvature of each surface indicates only the direction of curvature. When the curvature directions of the lenses on optical axis I and optical axis II are the same, the signs of the numerical values ​​of the radii of curvature are opposite. Similarly, the sign of the numerical value of the thickness / distance of each surface indicates only the direction. The curvature direction of each surface and the thickness / distance of each surface can be found by referring to... Figure 26 and Figure 27 .

[0278] Among them, the on-axis distance W1 between the second element group G2 and the third element group G3, and the on-axis distance W2 between the third element group G3 and the filter E9 are variables that can change with the distance between the subject and the optical system 900.

[0279] When the subject is at infinity, the optical system 900 is in its first state. A structural diagram of the optical system 900 can be found here. Figure 26 Wherein, W1 = -1.2964mm, W2 = -7.0189mm, the effective focal length (EFL) of optical system 900 is 27.73mm, the maximum field of view (FOV) of optical system 900 is 12.3122°, the aperture value (Fnox) of optical system 900 in the first direction is 3.3, and the aperture value (Fnoy) of optical system 900 in the second direction is 3.3. When the subject is a predetermined distance from optical system 900, optical system 900 is in its second state. A structural diagram of optical system 900 can be found here. Figure 27 .

[0280] In this embodiment, the object-side surface and image-side surface of any one of the lenses, from the first lens E1 to the eighth lens E8, are aspherical. Table 18 shows the conic coefficient K and higher-order coefficients A4, A6, A8, and A6 that can be used for the aspherical surfaces S1-S2 and S4-S17 in Embodiment 9. 10 A 12 A 14 A 16 A 18 and A 20 .

[0281] Table 18

[0282] S1 -305.477 -4.57E-02 -8.52E-03 -7.80E-05 -1.54E-04 1.00E-05 -1.80E-05 1.00E-06 -6.00E-06 2.00E-06 S2 90.000 -3.85E-02 -4.54E-04 2.47E-04 3.20E-05 2.60E-05 -7.00E-06 2.00E-06 -4.00E-06 2.00E-06 S4 -90.000 -1.26E-02 -1.86E-03 1.98E-04 -8.00E-06 -1.80E-05 1.30E-05 -8.00E-06 4.00E-06 -1.00E-06 S5 90.000 -2.14E-02 -1.36E-03 1.59E-04 -8.00E-06 -1.30E-05 1.00E-05 -9.00E-06 4.00E-06 -3.62E-08 S6 -90.000 -2.60E-01 5.51E-02 -2.01E-02 4.29E-03 -1.29E-03 -4.22E-04 -6.67E-04 -5.78E-04 -1.80E-04 S7 0.429 -5.43E-01 8.72E-02 -2.31E-02 1.05E-02 -2.46E-03 1.75E-03 2.30E-04 -5.48E-04 -2.81E-04 S8 0.054 1.14E+00 -5.70E-02 1.02E-02 -1.29E-03 -4.40E-04 -2.01E-04 -3.24E-04 -3.93E-04 -2.12E-04 S9 -2.311 6.13E-01 -7.94E-02 1.68E-02 -7.50E-03 3.07E-03 -3.27E-03 -1.11E-03 -3.74E-04 -4.80E-05 S10 -30.253 -2.14E-01 5.59E-02 -1.82E-02 -4.41E-04 5.60E-05 4.80E-04 -6.47E-04 5.00E-05 3.60E-05 S11 0.044 1.28E-02 8.08E-04 5.75E-04 -1.48E-03 2.51E-04 -4.80E-05 -3.71E-04 -2.80E-05 -1.00E-06 S12 0.114 -1.46E+00 1.46E-01 -3.31E-02 3.60E-03 -2.06E-03 8.91E-04 7.05E-04 -1.80E-04 -2.05E-04 S13 -60.755 -5.59E-01 3.75E-02 -3.43E-03 -2.76E-04 6.41E-04 -2.80E-05 -1.02E-04 -2.40E-05 1.00E-06 S14 -90.000 -6.69E-02 1.87E-02 8.48E-04 -8.16E-04 1.99E-04 -2.14E-04 -9.70E-05 -4.10E-05 -5.00E-06 S15 -0.798 -3.54E-02 9.86E-03 2.35E-03 -1.97E-03 8.75E-04 -9.19E-04 2.28E-04 -6.10E-05 -3.00E-06 S16 -20.271 5.77E-01 -7.72E-02 1.56E-02 -9.88E-03 -9.88E-04 -3.60E-03 1.17E-04 -8.66E-04 9.90E-05 S17 90.000 1.86E-01 -3.98E-03 2.23E-03 1.20E-03 -3.00E-06 -2.02E-04 -1.59E-04 -9.00E-05 -1.80E-05

[0283] Figure 28AThe on-axis chromatic aberration curve of the optical system 900 of Embodiment 9 is shown in the first state, which represents the deflection of the focal point of light of different wavelengths after passing through the optical system 900. Figure 28B The astigmatism curve of the optical system 900 of Embodiment 9 is shown in the first state, which represents the meridional image plane curvature and sagittal image plane curvature corresponding to different image heights. Figure 28C The distortion curve of the optical system 900 of Embodiment 9 in its first state is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 28A , Figure 28B and Figure 28C It can be seen that the optical system 900 of Embodiment 9 can achieve good imaging quality in the first state.

[0284] Table 19 shows the values ​​of parameters f1, f2, f3, f4, f5, f6, f7, f8, SL, SH, GH, D1, D2, D2x, D2y, fs1, fs2, SD1, SD2, FG12, FG3, EPDx, EPDy, α, and β for each embodiment in Examples 1 to 9. Among these, SL, SH, GH, α, and β can be determined according to... Figure 1A or Figure 1B The measurements were obtained using the annotation method shown. The units for parameters 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 for α and β are °.

[0285] Table 19

[0286]

[0287]

[0288] Table 20 shows the values ​​of the conditional expressions for each embodiment in Examples 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 using the FOV, EFL, EPDx, and EPDy of the optical system in the first state.

[0289] Table 20

[0290] Tan(α)×d12 0.22 1.38 0.66 0.41 0.18 1.68 0.61 1.10 0.82 Tan(α)×d12+Tan(β)×d23 0.24 1.44 0.67 0.43 0.20 1.69 0.62 1.13 0.86 d1P / dP2 1.00 0.68 0.83 0.87 0.96 1.03 0.96 0.87 0.82 (d1P+dP2) / SH 1.26 1.55 1.32 1.32 1.19 1.19 1.22 1.29 1.35 dP2 / SL 0.15 0.26 0.17 0.14 0.14 0.20 0.16 0.19 0.17 Tan (FOV / 2) 0.38 0.18 0.18 0.18 0.38 0.18 0.18 0.11 0.11 D1 / CT1 5.15 5.93 6.56 5.48 4.84 5.77 4.95 5.45 4.27 D2 / CT2 6.68 4.78 3.82 3.11 5.10 6.67 4.18 2.83 2.25 |f1 / f2| 0.25 0.87 0.99 0.91 0.53 0.97 0.87 0.89 0.79 |FG12 / EFL| 0.66 0.62 0.60 0.60 0.64 0.60 0.57 0.56 0.56 |FG12 / FG3| 0.92 0.95 0.94 0.92 0.96 1.01 0.95 1.00 0.97 |EFL / (FG12 / FG3)| 16.61 33.21 33.57 34.65 15.86 31.24 33.44 27.60 28.64 D2x / EPDx / d12 0.08 0.02 0.04 0.05 0.10 0.02 0.04 0.03 0.04 D2y / EPDy / d12 0.08 0.02 0.04 0.05 0.10 0.02 0.04 0.03 0.04 fs1 / fs2 -0.58 1.38 0.76 0.77 -0.59 0.70 0.60 1.04 1.84 EFL / SL 0.67 0.62 0.70 0.71 0.69 0.64 0.76 0.69 0.72 SD1 / SD2 1.03 1.03 1.00 0.97 0.97 1.09 0.98 1.00 0.99 OBJmin 17.00 10.00 10.00 10.00 17.00 10.00 10.00 10.00 10.00

[0291] This application also provides a camera module, which may be, for example, a periscope camera module. The camera module may include the aforementioned optical system and an imaging element for converting the optical image formed by the optical system into an electrical signal.

[0292] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. An optical system, characterized in that, The optical system comprises eight lenses with optical power, and the optical system includes, in sequence from the object side to the image side along the optical axis of the optical system: A first element group is used to reflect light. The first element group includes a first lens and a second lens. The first lens has positive optical power and its object side is convex. The second lens has negative optical power and its image side is concave. The first element group also includes a reflecting element, which is used to reflect light emitted from the first lens. The reflecting element is disposed between the first lens and the second lens. The second element group is fixed in position relative to the image plane disposed on the image side. The second element group includes a third lens, a fourth lens, and a fifth lens. The third lens has positive optical power, and the object side and image side of the third lens are convex. The fourth lens has negative optical power, and the object side and image side of the fourth lens are convex and concave. The fifth lens has positive optical power, and the image side of the fifth lens is convex. The third element group, the distance between the third element group and the second element group is adjustable, the third element group includes a sixth lens, a seventh lens and an eighth lens, the object side of the sixth lens is concave, the image side of the sixth lens is convex, the seventh lens has positive optical power, the image side of the seventh lens is convex, and the eighth lens has negative optical power. Wherein, the combined focal length FG12 of the first element group and the second element group, the effective focal length FG3 of the third element group and the effective focal length EFL of the optical system satisfy: 15.5mm < |EFL / (FG12 / FG3)| < 35.0mm.

2. The optical system according to claim 1, characterized in that, The combined focal length FG12 of the first element group and the second element group satisfies the following condition with respect to the effective focal length EFL of the optical system: 0.55≤|FG12 / EFL|≤0.

67.

3. The optical system according to claim 1, characterized in that, The combined focal length FG12 of the first element group and the second element group and the effective focal length FG3 of the third element group satisfy: 0.9 < |FG12 / FG3| < 1.

1.

4. The optical system according to claim 1, characterized in that, The optical axis includes a first optical axis and a second optical axis at a preset angle, and the effective focal length EFL of the optical system and the total length SL of the optical system along the direction of the second optical axis satisfy: 0.6 <EFL / SL<0.8。 5. The optical system according to claim 1, characterized in that, The maximum effective half-aperture SD1 of the lens closest to the object side in the second element group and the maximum effective half-aperture SD2 of another lens adjacent to the lens closest to the object side in the second element group satisfy: 0.95≤SD1 / SD2≤1.

12.

6. The optical system according to claim 1, characterized in that, The maximum field of view (FOV) of the optical system satisfies: 0.1 <Tan(FOV / 2)<0.4。 7. The optical system according to claim 1, characterized in that, The minimum object distance OBJmin of the optical system satisfies: OBJmin≥10cm.

8. The optical system according to claim 1, characterized in that, The effective focal length f1 of the first lens and the effective focal length f2 of the second lens satisfy: |f1 / f2|≤1.

0.

9. The optical system according to claim 1, characterized in that, The optical axis includes a first optical axis and a second optical axis at a preset angle, and the maximum effective half-aperture D1 of the first lens and the center thickness CT1 of the first lens on the first optical axis satisfy: 4.2 <D1 / CT1<6.6。 10. The optical system according to claim 1, characterized in that, The optical axis includes a first optical axis and a second optical axis at a preset angle. The distance dP2 between the image-side surface of the reflecting element and the second lens on the second optical axis satisfies the following condition: 0.1 <dP2 / SL<0.3。 11. The optical system according to claim 1, characterized in that, The optical axis includes a first optical axis and a second optical axis at a preset angle, and the maximum effective half-aperture D2 of the second lens and the center thickness CT2 of the second lens on the second optical axis satisfy: 2.2 <D2 / CT2<6.8。 12. The optical system according to claim 1, characterized in that, The optical axis includes a first optical axis and a second optical axis at a preset angle. The maximum effective half-aperture D2x of the second lens in the first direction, the entrance pupil diameter EPDx of the optical system in the first direction, and the axial distance d12 from the image side of the first lens to the object side of the second lens satisfy: 0.02mm. -1 ≤D2x / EPDx / d12≤0.10mm -1 The first direction is perpendicular to the plane formed by the first optical axis and the second optical axis.

13. The optical system according to claim 1, characterized in that, The optical axis includes a first optical axis and a second optical axis at a preset angle. The maximum effective half-aperture D2y of the second lens in the second direction, the entrance pupil diameter EPDy of the optical system in the second direction, and the axial distance d12 from the image side of the first lens to the object side of the second lens satisfy: 0.02mm. -1 ≤D2y / EPDy / d12≤0.10mm -1 The second direction is parallel to the first optical axis.

14. The optical system according to claim 1, characterized in that, The effective focal length fs1 of the object side of the first lens and the effective focal length fs2 of the image side of the first lens satisfy: -0.60 <fs1 / fs2<1.85。 15. The optical system according to claim 1, characterized in that, The reflecting element includes a plane mirror.

16. A camera module, characterized in that, It includes an optical system as described 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