A method for determining a cam profile curve of an optical lens with a short actuation group travel

Abstract

The application provides an optical lens with a short moving group stroke, which comprises a front fixed group, the front fixed group comprising a first lens, the first surface being a convex spherical surface and the second surface being a concave aspherical surface; a moving group comprising, in sequence along the light entering direction, a zooming group, a compensation group and a focusing group arranged on one side of the compensation group; the zooming group comprising a second lens, the first surface being a plane and the second surface being a concave aspherical surface; the compensation group comprising a third lens and a fourth lens, the first surfaces of the third lens and the fourth lens being convex aspherical surfaces and the second surfaces of the third lens and the fourth lens being concave spherical surfaces; the focusing group comprising a fifth lens close to the fourth lens and a sixth lens away from the fourth lens, the first surface of the fifth lens being a concave spherical surface, the second surface of the fifth lens being a convex aspherical surface, the first surface of the sixth lens being a concave spherical surface and the second surface of the sixth lens being a convex aspherical surface; and a driving assembly used for driving the second lens, the third lens and the fourth lens to move along the optical axis with corresponding movement paths. The optical lens can realize high-quality imaging within a short moving group stroke.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of optical systems, in particular to an optical lens with a short moving group stroke and a determination method of a cam profile curve. BACKGROUND

[0002] With the continuous development of science and technology, optical lenses are increasingly widely used in various fields such as photography, monitoring, medical treatment, etc. However, existing optical lenses often have problems such as large size, low imaging quality, and inflexible zooming and focusing performance.

[0003] In some specific application scenarios, an optical lens with a short moving group stroke is needed to meet the requirements of device miniaturization and high performance. At the same time, in the process of zooming and focusing, traditional optical lenses may have problems such as large change in aberration and poor imaging stability, which affect the imaging quality. SUMMARY

[0004] In view of the above defects or deficiencies in the prior art, the present application aims to provide an optical lens with a short moving group stroke and a determination method of a cam profile curve;

[0005] In a first aspect, the present application provides an optical lens with a short moving group stroke, comprising:

[0006] A front fixed group, the front fixed group comprising a first lens, the first surface of the first lens being a convex spherical surface, and the second surface being a concave aspherical surface;

[0007] A moving group, the moving group comprising a zooming group and a compensation group in sequence along the direction of light incidence;

[0008] A focusing group, the focusing group being arranged on the side of the compensation group away from the zooming group;

[0009] The zooming group comprises a second lens, the first surface of the second lens being a plane, and the second surface being a concave aspherical surface;

[0010] The compensation group comprises a third lens close to the second lens and a fourth lens away from the second lens, the first surfaces of the third lens and the fourth lens being convex aspherical surfaces, and the second surfaces being concave spherical surfaces;

[0011] The focusing group comprises a fifth lens close to the fourth lens and a sixth lens away from the fourth lens, the first surface of the fifth lens being a concave spherical surface, and the second surface being a convex aspherical surface, the first surface of the sixth lens being a concave spherical surface, and the second surface being a convex aspherical surface; the second lens, the third lens and the fourth lens have a motion path corresponding to the magnification of the compensation group;

[0012] The first driving assembly is used for driving the second lens, the third lens and the fourth lens to move along the optical axis with corresponding movement paths.

[0013] The second driving assembly is used for driving the focusing group to move to compensate for the phase difference in an environment with a temperature higher or lower than normal temperature.

[0014] The first surface is a lens surface through which light enters, and the second surface is a lens surface through which light exits.

[0015] According to the technical scheme provided in the embodiments of the present application, each lens has a lens holder; the first driving assembly comprises a motor, the output end of the motor is connected with a cam, the extension direction of the cam is the same as the extension direction of the optical axis, the profile of the cam comprises a first curve, a second curve and a third curve connected in sequence, the first curve corresponds to the movement path of the second lens, the second curve corresponds to the movement path of the third lens, and the third curve corresponds to the movement path of the fourth lens.

[0016] According to the technical scheme provided in the embodiments of the present application, the optical material of the first lens is silicon crystal glass, the radius of the first surface is 50mm-60mm, the radius of the second surface is 100mm-110mm, the clear aperture is φ55mm-φ57mm and φ51mm-φ53mm in sequence, and the thickness is 7mm-8mm.

[0017] According to the technical scheme provided in the embodiments of the present application, the optical material of the second lens is germanium glass, the first surface is a plane, the radius of the second surface is 15mm-25mm, the clear aperture is φ14mm-φ16mm and φ13.5mm-φ15.5mm in sequence, and the thickness is 1.4mm-2.5mm.

[0018] According to the technical scheme provided in the embodiments of the present application, the optical material of the third lens is silicon crystal glass, the first surface is a non-spherical base diffraction surface, the radius of the first surface is 15mm-17mm, the radius of the back surface is 45mm-55mm, the clear aperture is φ15mm-φ17mm and φ14mm-φ16mm in sequence, and the thickness is 4mm-5mm.

[0019] According to the technical scheme provided in the embodiments of the present application, the optical material of the fourth lens is zinc selenide, the radius of the first surface is 20mm-30mm, the radius of the second surface is 465mm-485mm, the clear aperture is φ11.5mm-φ13.5mm and φ10mm-φ12mm in sequence, and the thickness is 3mm-4mm.

[0020] According to the technical solution provided in the embodiments of this application, the optical material of the fifth lens is zinc sulfide, the radius of the first surface is 5mm-7mm, the radius of the second surface is 7mm-9mm, the light transmission aperture is φ4mm-φ5mm and φ7mm-φ9mm respectively, and the thickness is 4mm-5mm.

[0021] According to the technical solution provided in the embodiments of this application, the optical material of the sixth lens is silicon crystal glass, the radius of the first surface is 20mm-30mm, the second surface is aspherical, the radius of the rear surface is 10mm-20mm, the light transmission aperture is φ9mm~φ11mm and φ10mm-φ12mm respectively, and the thickness is 4mm-5mm.

[0022] According to the technical solution provided in the embodiments of this application, the distance between the first lens and the second lens is 22mm-27.5mm; the distance between the second lens and the third lens is 0.8mm-12mm; the distance between the third lens and the fourth lens is 1mm-12mm; the distance between the fourth lens and the fifth lens is 2mm-8mm; the distance between the fifth lens and the sixth lens is 2.42mm; and the distance between the sixth lens and the detector window is 3mm-3.5mm.

[0023] Secondly, this application proposes a method for determining the profile curve of a cam, used to determine the profile curve of a cam in an optical lens with a short-stroke movement as described above; including the following steps:

[0024] The profile curve equation of the cam is determined, which characterizes the relationship between the geometric parameters of the cam and the displacement of the compensation group; the geometric parameters include at least the rotation angle.

[0025] With the goals of correcting the second-order spectrum, reducing the overall system length, and achieving lightweight, compact, high-magnification continuous zoom, target optimization indicators are determined. These target optimization indicators include at least minimizing the second-order spectrum deviation, minimizing the overall system length, and maximizing the zoom ratio.

[0026] A multi-objective optimization strategy is adopted to optimize the profile curve of the cam in order to obtain the profile curve of the cam.

[0027] According to the technical solution provided in the embodiments of this application, the optical lens has a working wavelength of 3.7μm-4.8μm, an F number of 4, a total length of 70mm, and a focal length that continuously zooms from 45mm to 215mm.

[0028] In summary, this application proposes an optical lens with a short moving-group travel, comprising a front fixed group, which includes a first lens having a first surface that is a convex spherical surface and a second surface that is a concave aspherical surface; a moving group, which sequentially includes a zoom group and a compensation group along the light incident direction, with a focusing group on the side of the compensation group away from the zoom group; the zoom group includes a second lens having a first surface that is a plane and a second surface that is a concave aspherical surface; the compensation group includes a third lens near the second lens and a fourth lens on the side of the third lens away from the second lens, both the third and fourth lenses having first surfaces that are convex aspherical surfaces, the second... All surfaces are concave spherical; the focusing group includes a fifth lens near the fourth lens and a sixth lens away from the fourth lens. The first surface of the fifth lens is a concave spherical surface and the second surface is a convex aspherical surface. The first surface of the sixth lens is a concave spherical surface and the second surface is a convex aspherical surface. The second, third, and fourth lenses have corresponding motion paths. The driving component is at least used to drive the second, third, and fourth lenses to move along the optical axis along a motion path corresponding to the magnification of the compensation group. The first surface is the lens surface into which light enters, and the second surface is the lens surface into which light exits.

[0029] Compared with existing technologies, the beneficial effects of this application are as follows: This application controls the magnification of the compensation group, allowing it to change rapidly, thereby achieving a fast change in the distance between the compensation group and the zoom group. This reduces the travel of the moving group, making the overall structure of the optical lens more compact and facilitating device miniaturization. In applications with high space requirements, such as portable devices and miniature cameras, optical lenses with short moving group travel better meet design needs, reducing the mechanical movement distance of the lens during zooming and focusing, and improving the lens's response speed and stability. Simultaneously, the first lens of the front fixed group uses a convex spherical and concave aspherical design, effectively correcting spherical aberration and coma, improving image quality. The second lens of the zoom group has a planar first surface and a concave aspherical second surface, which helps control the light propagation path and achieve zoom functionality. The third and fourth lenses of the compensation group both have convex aspherical first surfaces and concave spherical second surfaces, compensating for aberrations during zooming and ensuring image stability. The special surface design of the fifth and sixth lenses of the focusing group makes focusing more precise and improves image clarity. Therefore, this optical lens can achieve high-quality imaging within a short motion range. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of an optical lens with a short motion group stroke provided in an embodiment of this application;

[0031] Figure 2 A schematic diagram of a short-motion optical lens in zoom mode provided in an embodiment of this application;

[0032] Figure 3 A schematic diagram of the first curve, second curve, and third curve of the cam provided in the embodiments of this application;

[0033] Figure 4 A flowchart illustrating the steps of the method for determining the cam profile curve provided in this application embodiment;

[0034] Figure 5 The transfer function curve of the optical system at +20°C for the short focal length (f=45mm) of the optical lens provided in the embodiments of this application;

[0035] Figure 6 The transfer function curve of the optical system at +20°C when the optical lens provided in the embodiment of this application is at the mid-focal length (f=125mm);

[0036] Figure 7 The transfer function curve of the optical system at +20°C for the telephoto (f=215mm) optical lens provided in the embodiments of this application;

[0037] Figure 8 The transfer function curve of the optical system at +60°C for the short focal length (f=45mm) of the optical lens provided in the embodiments of this application;

[0038] Figure 9 The transfer function curve of the optical system at +60°C when the optical lens provided in the embodiment of this application is at the mid-focal length (f=125mm);

[0039] Figure 10 The transfer function curve of the optical system at +60°C for the telephoto (f=215mm) optical lens provided in the embodiments of this application;

[0040] Figure 11 The transfer function curve of the optical system at -40°C for the short focal length (f=45mm) of the optical lens provided in the embodiments of this application;

[0041] Figure 12 The transfer function curve of the optical system at -40°C when the optical lens provided in the embodiment of this application is at the mid-focal length (f=125mm);

[0042] Figure 13 The transfer function curve of the optical system at -40°C for the telephoto (f=215mm) optical lens provided in the embodiments of this application;

[0043] Figure 14 A relative distortion curve of the optical system when the optical lens is at a short focal length (f=45mm) according to an embodiment of this application;

[0044] Figure 15A relative distortion curve of the optical system at the mid-focal length (f = 125mm) of the optical lens provided in the embodiments of this application;

[0045] Figure 16 The relative distortion curve of the optical system when the optical lens is at a telephoto distance (f=215mm) according to the embodiments of this application.

[0046] The text labels in the image represent:

[0047] 1. First lens; 2. Second lens; 3. Third lens; 4. Fourth lens; 5. Fifth lens; 6. Sixth lens; 7. Detector. Detailed Implementation

[0048] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0049] 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.

[0050] Example 1

[0051] As mentioned in the background section, this application proposes an optical lens with a short motion group stroke to address the problems in the prior art. Please refer to [link / reference]. Figure 1 As shown, it includes:

[0052] The front fixing assembly includes a first lens 1, the first surface of which is a convex spherical surface and the second surface is a concave aspherical surface (it should be noted that, from...) Figure 1 The first surface of the first lens 1 appears to be spherical due to its large radius; in fact, the second surface is a concave aspherical surface.

[0053] The moving group, along the direction of light incidence, includes a zoom group and a compensation group in sequence.

[0054] A focusing group is located on the side of the compensation group away from the zoom group;

[0055] The zoom group includes a second lens 2, the first surface of the second lens 2 is a plane, and the second surface is a concave aspherical surface;

[0056] The compensation group includes a third lens 3 close to the second lens 2 and a fourth lens 4 away from the second lens 2. The first surfaces of the third lens 3 and the fourth lens 4 are both convex aspherical surfaces, and the second surfaces are both concave spherical surfaces.

[0057] The focusing group includes a fifth lens 5 located near the fourth lens 4 and a sixth lens 6 located away from the fourth lens 4. The first surface of the fifth lens 5 is a concave spherical surface and the second surface is a convex aspherical surface. The first surface of the sixth lens 6 is a concave spherical surface and the second surface is a convex aspherical surface. The second lens 2, the third lens 3, and the fourth lens 4 have motion paths corresponding to the magnification of the compensation group.

[0058] A first driving component is used to drive the second lens 2, the third lens 3, and the fourth lens 4 to move along the optical axis along corresponding motion paths;

[0059] The second driving component is used to drive the focusing group to move in order to compensate for phase difference in environments with temperatures higher or lower than normal. Specifically, in order to improve image quality and make the image clearer, the second driving component does not operate in normal temperature environments, that is, the focusing group does not operate.

[0060] Wherein, the first surface is the lens surface on which light enters, and the second surface is the lens surface on which light exits.

[0061] Specifically, along a defined optical axis, the mid-wave infrared radiation from the target area is arranged in the following order from the object side to the image side: a front fixed group with positive optical power, a zoom group consisting of a plano-concave lens with negative optical power, a compensation group consisting of two meniscus lenses with positive optical power arranged sequentially, and a rear fixed group consisting of two meniscus lenses with positive optical power arranged sequentially. This projects the mid-wave infrared radiation within the field of view onto the focal plane, thereby achieving image formation of the target.

[0062] This invention reduces the travel of the moving group by controlling the magnification of the compensation group, allowing for rapid changes in magnification and thus a faster change in the distance between the compensation and zoom groups. However, a shorter travel of the moving group increases the cam curve lift angle. Therefore, while ensuring cam manufacturability, the travel of the zoom and compensation groups is shortened. During the design process, the aperture of the zoom and compensation group lenses is controlled, thereby reducing the size of the zoom cam, zoom group mount, and compensation group mount. This achieves a compact and lightweight design for the continuous zoom optical lens. Ultimately, the optical lens of this invention can achieve continuous zoom from 45mm to 215mm within a total length of 70mm.

[0063] In a preferred embodiment, each lens has a lens mount; the first drive assembly includes a motor, the output end of which is connected to a cam, the extension direction of which is the same as the extension direction of the optical axis, and the profile of the cam includes at least a first curve, a second curve, and a third curve connected end to end, the first curve corresponding to the movement path of the second lens 2, the second curve corresponding to the movement path of the third lens 3, and the third curve corresponding to the movement path of the fourth lens 4.

[0064] In a preferred embodiment, the optical material of the first lens 1 is silicon crystal glass, the radius of the first surface is 50mm-60mm, the radius of the second surface is 100mm-110mm, the light transmission aperture is φ55mm-φ57mm and φ51mm-φ53mm respectively, and the thickness is 7mm-8mm.

[0065] In a preferred embodiment, the optical material of the second lens 2 is germanium glass, the first surface is a plane, the radius of the second surface is 15mm-25mm, the light transmission aperture is φ14mm-φ16mm and φ13.5mm-φ15.5mm respectively, and the thickness is 1.4mm-2.5mm.

[0066] In a preferred embodiment, the optical material of the third lens 3 is silicon crystal glass, the first surface is an aspherical substrate diffraction surface, the radius of the first surface is 15mm-17mm, the radius of the rear surface is 45mm-55mm, the light transmission aperture is φ15mm-φ17mm and φ14mm-φ16mm respectively, and the thickness is 4mm-5mm.

[0067] In a preferred embodiment, the optical material of the fourth lens 4 is zinc selenide, the radius of the first surface is 20mm-30mm, the radius of the second surface is 465mm-485mm, the light transmission aperture is φ11.5mm-φ13.5mm and φ10mm-φ12mm respectively, and the thickness is 3mm-4mm.

[0068] In a preferred embodiment, the optical material of the fifth lens 5 is zinc sulfide, the radius of the first surface is 5mm-7mm, the radius of the second surface is 7mm-9mm, the light transmission aperture is φ4mm-φ5mm and φ7mm-φ9mm respectively, and the thickness is 4mm-5mm.

[0069] In a preferred embodiment, the optical material of the sixth lens 6 is silicon glass, the radius of the first surface is 20mm-30mm, the second surface is aspherical, the radius of the rear surface is 10mm-20mm, the light transmission aperture is φ9mm~φ11mm and φ10mm-φ12mm respectively, and the thickness is 4mm-5mm.

[0070] In a preferred embodiment, the distance between the first lens 1 and the second lens 2 is 22mm-27.5mm; the distance between the second lens 2 and the third lens 3 is 0.8mm-12mm; the distance between the third lens 3 and the fourth lens 4 is 1mm-12mm; the distance between the fourth lens 4 and the fifth lens 5 is 2mm-8mm; the distance between the fifth lens 5 and the sixth lens 6 is 2.42mm; and the distance between the sixth lens 6 and the detector 7 window is 3mm-3.5mm.

[0071] In a preferred embodiment, the optical lens operates in the 3.7μm-4.8μm wavelength range, has an F-number of 4, and a total length of 70mm. Please refer to [reference needed]. Figure 2 As shown, the focal length continuously zooms from 45mm to 215mm.

[0072] Furthermore, the maximum distortion across the entire field of view of this optical lens is less than 2.9% throughout the entire zoom process, the optical lens weighs 39.3 grams, and the image plane position remains unchanged throughout the entire zoom process, enabling clear imaging at a fixed F-number.

[0073] The fitting of the cam curve is based on the condition of ensuring image plane stability and excellent image quality. In this design, the zoom group and the compensation group move in curves with a certain step size under the drive of the cam. By optimizing the cam curve of the zoom group, the rise angle of the curves of the three motion groups is less than 40°. In addition, the image transformation rate is smooth throughout the zoom process, and the visual effect is more comfortable.

[0074] The fitting of the cam curve was designed to ensure image plane stability and good image quality. Five focal length positions were selected for system optimization. A macro program (CODE V) was used to optimize the cam curves of each moving group, resulting in the following... Figure 3 The cam curves are shown, with each moving group's motion curve being smooth and without inflection points. In the figure, the vertical axis represents the interval value of each moving group's movement along the optical axis at different focal lengths, and the horizontal axis represents the number of points. The curves, from bottom to top, represent the second lens 2 of the zoom group, the third lens 3 of the compensation group, and the fourth lens 4 of the compensation group. As can be seen from the figure, each cam curve is smooth. Fitting the obtained data yields the cam curve equation, which is then used to machine the cam.

[0075] Figure 5 , Figure 6 and Figure 7To create the optimal embodiment optical transfer function (OPF) curve using Code V optical design software, the input wavelengths were designed to be 3.7 μm, 4.25 μm, and 4.8 μm, with half-image heights of 0, 1.23, 3.08, 4.31, and 6.15, and an F-number of 4. Since the image quality is the same in both the positive and negative directions, only the positive image height is used as input. In the figure, the horizontal axis represents spatial frequency, and the vertical axis represents the ORF value. Furthermore, Figure 8 - Figure 16 It can also be seen that the optical lens proposed in this application meets the performance requirements.

[0076] Table 1 shows the imaging quality of the low-cost, lightweight, high-magnification continuous zoom optical lens at different focal lengths. It can be seen that the optical system exhibits excellent imaging quality from the center field of view to the edge field of view within a focal length range of 45mm-215mm. In summary, this invention achieves the design requirements of a low-cost, lightweight, high-magnification, and continuous zoom optical lens.

[0077] Table 1 Image Quality of Low-Cost, Lightweight, High-Magnification Continuous Zoom Lenses

[0078] focal length 45mm 125mm 215mm relative field of view theoretical theoretical theoretical 0 0.323 0.332 0.271 0.3 0.295 0.299 0.241 0.5 0.251 0.251 0.186 0.7 0.198 0.201 0.142 1 0.136 0.145 0.117

[0079] Example 2

[0080] Based on Example 1, this example proposes a method for determining the cam profile curve, used to determine the cam profile curve in an optical lens with a short-stroke optical group as described above; please refer to... Figure 4 As shown, it includes the following steps:

[0081] S1. Determine the profile curve equation of the cam, wherein the profile curve equation is used to characterize the relationship between the geometric parameters of the cam and the displacement of the compensation group; the geometric parameters include at least the rotation angle.

[0082] Further analysis of the relationship between the displacement of the compensation group and the magnification is conducted, establishing a functional expression for the magnification with respect to the geometric parameters of the cam. Using optical design software, the performance of the optical system under different cam geometric parameters is simulated, including the correction of the second-order spectrum, image quality, and overall system length. The influence of magnification on the second-order spectrum correction and the trade-off between it and the overall system length are determined.

[0083] S2. With the goals of correcting the secondary spectrum, reducing the total system length, and achieving lightweight, compact, high zoom ratio continuous zoom, determine the target optimization indicators. The target optimization indicators include at least minimizing the secondary spectrum deviation, minimizing the total system length, and maximizing the zoom ratio.

[0084] Specifically, optimization algorithms such as genetic algorithms and simulated annealing algorithms are used. During the optimization process, the geometric parameters of the cam are continuously adjusted to meet the requirements of the optimization objective.

[0085] S3. A multi-objective optimization strategy is adopted to optimize the profile curve of the cam to obtain the profile curve of the cam.

[0086] A multi-objective optimization strategy can be adopted. Optionally, weighted summation, Pareto optimization, and other methods can be used to balance and optimize among multiple objectives in order to obtain the profile curve of the cam that minimizes the second-order spectral deviation, minimizes the total system length, and maximizes the zoom ratio.

[0087] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this invention, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. An optical lens with a short motion group stroke, characterized in that, include: The front fixing group includes a first lens (1), the first surface of the first lens (1) is a convex spherical surface, and the second surface is a concave aspherical surface; The moving group, along the direction of light incidence, includes a zoom group and a compensation group in sequence. A focusing group is located on the side of the compensation group away from the zoom group; The zoom group includes a second lens (2), the first surface of the second lens (2) is a plane, and the second surface is a concave aspherical surface; The compensation group includes a third lens (3) close to the second lens (2) and a fourth lens (4) away from the second lens (2). The first surfaces of the third lens (3) and the fourth lens (4) are both convex aspherical surfaces, and the second surfaces are both concave spherical surfaces. The focusing group includes a fifth lens (5) close to the fourth lens (4) and a sixth lens (6) away from the fourth lens (4). The first surface of the fifth lens (5) is a concave spherical surface and the second surface is a convex aspherical surface. The first surface of the sixth lens (6) is a concave spherical surface and the second surface is a convex aspherical surface. The second lens (2), the third lens (3), and the fourth lens (4) have motion paths corresponding to the magnification of the compensation group. A first driving component is used to drive the second lens (2), the third lens (3), and the fourth lens (4) to move along the optical axis along corresponding motion paths; A second drive assembly is used to drive the focusing group to move in order to compensate for phase difference in environments with temperatures above or below normal. Wherein, the first surface is the lens surface into which light enters, and the second surface is the lens surface into which light exits; the optical lens has six lenses with optical power, and the first lens (1) has positive optical power, the second lens (2) has negative optical power, the third lens (3) has positive optical power, the fourth lens (4) has positive optical power, the fifth lens (5) has positive optical power, and the sixth lens (6) has positive optical power; The distance between the first lens (1) and the second lens (2) is 22mm-27.5mm; the distance between the second lens (2) and the third lens (3) is 0.8mm-12mm; the distance between the third lens (3) and the fourth lens (4) is 1mm-12mm; the distance between the fourth lens (4) and the fifth lens (5) is 2mm-8mm; the distance between the fifth lens (5) and the sixth lens (6) is 2.42mm; and the distance between the sixth lens (6) and the detector (7) window is 3mm-3.5mm.

2. The optical lens with a short motion group stroke according to claim 1, characterized in that: Each lens has a lens mount; the first drive assembly includes a motor, the output end of which is connected to a cam, the extension direction of which is the same as the extension direction of the optical axis, and the profile curve of the cam includes at least a first curve, a second curve and a third curve connected end to end, the first curve corresponds to the movement path of the second lens (2), the second curve corresponds to the movement path of the third lens (3), and the third curve corresponds to the movement path of the fourth lens (4).

3. The optical lens with a short motion group stroke according to claim 1, characterized in that: The optical material of the first lens (1) is silicon crystal glass, the radius of the first surface is 50mm-60mm, the radius of the second surface is 100mm-110mm, the light transmission aperture is φ55mm-φ57mm and φ51mm-φ53mm respectively, and the thickness is 7mm-8mm.

4. The optical lens with a short motion group stroke according to claim 1, characterized in that: The optical material of the second lens (2) is germanium glass. The first surface is a plane, the radius of the second surface is 15mm-25mm, the light transmission aperture is φ14mm-φ16mm and φ13.5mm-φ15.5mm respectively, and the thickness is 1.4mm-2.5mm.

5. The optical lens with a short motion group stroke according to claim 1, characterized in that: The optical material of the third lens (3) is silicon crystal glass. The first surface is an aspherical substrate diffraction surface with a radius of 15mm-17mm and a rear surface radius of 45mm-55mm. The light transmission aperture is φ15mm-φ17mm and φ14mm-φ16mm respectively, and the thickness is 4mm-5mm.

6. The optical lens with a short motion group stroke according to claim 1, characterized in that: The optical material of the fourth lens (4) is zinc selenide. The radius of the first surface is 20mm-30mm, the radius of the second surface is 465mm-485mm, the light transmission aperture is φ11.5mm-φ13.5mm and φ10mm-φ12mm respectively, and the thickness is 3mm-4mm.

7. The optical lens with a short motion group stroke according to claim 1, characterized in that: The optical material of the fifth lens (5) is zinc sulfide, the radius of the first surface is 5mm-7mm, the radius of the second surface is 7mm-9mm, the light transmission aperture is φ4mm-φ5mm and φ7mm-φ9mm respectively, and the thickness is 4mm-5mm.

8. The optical lens with a short motion group stroke according to claim 1, characterized in that: The optical material of the sixth lens (6) is silicon crystal glass. The radius of the first surface is 20mm-30mm, the second surface is aspherical, the radius of the rear surface is 10mm-20mm, the light transmission aperture is φ9mm~φ11mm and φ10mm-φ12mm respectively, and the thickness is 4mm-5mm.

9. A method for determining a cam profile curve, used to determine the profile curve of a cam in an optical lens with a short-stroke movement as described in any one of claims 2-8; characterized in that: Includes the following steps: The profile curve equation of the cam is determined, which characterizes the relationship between the geometric parameters of the cam and the displacement of the compensation group; the geometric parameters include at least the rotation angle. With the goals of correcting the second-order spectrum, reducing the overall system length, and achieving lightweight, compact, high-magnification continuous zoom, target optimization indicators are determined. These target optimization indicators include at least minimizing the second-order spectrum deviation, minimizing the overall system length, and maximizing the zoom ratio. A multi-objective optimization strategy is adopted to optimize the profile curve of the cam in order to obtain the profile curve of the cam.

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