Zoom lens and monitoring device

Abstract

The utility model discloses a zoom lens and a monitoring device, and relates to the technical field of optical systems, the zoom lens is provided with an optical axis extending along a first direction, namely an object side and an image side which are oppositely arranged in the first direction, and the zoom lens comprises a first lens group to a seventh lens group which are sequentially arranged from the object side to the image side; the second lens group, the fourth lens group and the fifth lens group are movably arranged in the optical axis direction for zooming; the sixth lens group is movably arranged in the optical axis direction and is used for focusing; the third lens group has a movement stroke that translates in a direction perpendicular to the first direction and a rotation stroke that rotates about a rotation axis in the first direction. According to the utility model, the third lens group is movably arranged and is used for adjusting the imaging position during shaking so as to form a clear image.

Description

Technical Field

[0001] The utility model relates to the technical field of optical systems, in particular to a zoom lens and monitoring equipment. Background Art

[0002] In recent years, as the use scenarios of monitoring equipment in the security field have become increasingly complex, the requirements have become higher and higher, and people have also had higher-level demands on security. In response to the monitoring needs in different environments, people are paying more and more attention to the pursuit of imaging effects and imaging range. They hope to be able to meet both wide-field imaging searches under a large field of view and precise tracking and observation under a small field of view. Therefore, the demand for zoom lenses with relatively large magnification is becoming increasingly greater.

[0003] At the same time, most monitoring scenes are generally outdoors where there is jitter or certain interference in the working environment. Moreover, when the large-magnification zoom optical lens is at the telephoto end, due to the relatively small viewing angle of the monitoring equipment, various factors such as wind blowing or shaking when installed at high places make it difficult for the large-magnification zoom optical lens to maintain a stable working state, resulting in image jitter and difficulty in capturing the subject normally, affecting the normal use of the monitoring equipment. Therefore, the demand for the development of zoom optical lenses that have both large-magnification functions and anti-shake design has become increasingly strong. Utility Model Content

[0004] The main purpose of the utility model is to provide a zoom lens and monitoring equipment, aiming to provide a zoom optical lens with a large magnification adjustment range and an anti-shake function.

[0005] To achieve the above-mentioned purpose, the zoom lens proposed in the utility model has an optical axis extending along a first direction, and has an object side and an image side arranged opposite to each other in the first direction. The zoom lens includes a first lens group, a second lens group, a third lens group, a fourth lens group, a fifth lens group, a sixth lens group, and a seventh lens group arranged in sequence from the object side to the image side; the first lens group, the third lens group, the fifth lens group, and the seventh lens group have positive optical focal length; the second lens group, the fourth lens group, and the sixth lens group have negative optical focal length; wherein the second lens group, the fourth lens group, and the fifth lens group are movably arranged along the optical axis direction for zooming; the sixth lens group is movably arranged along the optical axis direction for focusing; the third lens group has a moving stroke for translation along a vertical first direction, and a rotation stroke for rotation around a rotation axis along the first direction.

[0006] In one embodiment, the movable range of the moving stroke is A31, 0.2mm≥A31≥0mm;

[0007] The rotation range of the rotation stroke is A32, 0.2°≥A32≥-0.2°.

[0008] In one embodiment, the movable travel of the second lens group in the optical axis direction is A2, and A2 ≥ 41.8 mm;

[0009] The movable stroke of the fourth lens group in the optical axis direction is A4, A4 ≥ 4.2 mm;

[0010] The movable stroke of the fifth lens group in the optical axis direction is A5, A5≥13.3mm;

[0011] The movable stroke of the sixth lens group in the optical axis direction is A6, A6≥20.3mm

[0012] The zoom lens has an adjustable focal length range of greater than or equal to 6.4 mm and less than or equal to 250 mm; and an adjustable aperture number range of greater than or equal to 1.69 and less than or equal to 4.92.

[0013] In one embodiment, the total optical length of the zoom lens is TTL, TTL≤139 mm; and satisfies:

[0014] 0.262≤A2 / TTL≤0.340; 0.026≤A4 / TTL≤0.034; 0.083≤A5 / TTL≤0.108; 0.127≤A6 / TTL≤0.165.

[0015] In one embodiment, the focal length of the zoom lens is adjustable within a range of greater than or equal to 6.4 mm and less than or equal to 250 mm, and the focal length F of the zoom lens in a wide-angle state is F=6.4 mm;

[0016] The focal length of the first lens group is f1, 0.085≤F / f1≤0.115; the first lens group includes a first lens, a second lens, a third lens, and a fourth lens arranged in sequence from the object side to the image side;

[0017] The focal length of the first lens is f11, -0.692≤f1 / f11≤-0.511;

[0018] The focal length of the second lens is f12, 0.487≤f1 / f12≤0.659;

[0019] The focal length of the third lens is f13, 0.387≤f1 / f13≤0.523;

[0020] The focal length of the fourth lens is f14, 0.495≤f1 / f14≤0.670;

[0021] The focal length of the second lens group is f2, -0.720≤F / f2≤-0.532;

[0022] The second lens group includes a fifth lens, a sixth lens, and a seventh lens arranged in sequence from the object side to the image side;

[0023] The focal length of the fifth lens is f21, 0.519≤f2 / f21≤0.703;

[0024] The focal length of the sixth lens is f22, 0.556≤f2 / f22≤0.753;

[0025] The focal length of the seventh lens is f23, -0.414≤f2 / f23≤-0.306;

[0026] The focal length of the third lens group is f3, 0.353≤F / f3≤0.478;

[0027] The third lens group includes an eighth lens and a ninth lens;

[0028] The focal length of the eighth lens is f31, 0.518≤f3 / f31≤0.701;

[0029] The focal length of the ninth lens is f32, 0.383≤f3 / f32≤0.518;

[0030] The focal length of the fourth lens group is f4, -0.595≤F / f4≤-0.440; the fourth lens group includes a tenth lens;

[0031] The focal length of the tenth lens is f41, 0.850≤f4 / f41≤1.150;

[0032] The focal length of the fifth lens group is f5, 0.309≤F / f5≤0.418;

[0033] The fifth lens group includes an eleventh lens, a twelfth lens, and a thirteenth lens arranged in sequence from the object side to the image side;

[0034] The focal length of the eleventh lens is f51, 0.830≤f5 / f51≤1.123;

[0035] The focal length of the twelfth lens is f52, -1.148≤f5 / f52≤-0.849;

[0036] The focal length of the thirteenth lens is f53, 0.882≤f5 / f53≤1.194;

[0037] The focal length of the sixth lens group is f6, -0.325≤F / f6≤-0.276; the sixth lens group includes a fourteenth lens;

[0038] The focal length of the fourteenth lens is f61, 0.850≤f6 / f61≤1.150;

[0039] The focal length of the seventh lens group is f7, 0.196≤F / f7≤0.265; the seventh lens group includes a fifteenth lens;

[0040] The focal length of the fifteenth lens is f71, 0.850≤f7 / f71≤1.150.

[0041] In one embodiment, the first lens, the second lens, the third lens, the fourth lens, the sixth lens, the seventh lens, the ninth lens, the twelfth lens, and the thirteenth lens are all configured as spherical lenses;

[0042] The fifth lens, the eighth lens, the tenth lens, the eleventh lens, the fourteenth lens, and the fifteenth lens are all configured as aspherical lenses.

[0043] In one implementation, the first lens is cemented to the second lens, the sixth lens is cemented to the seventh lens, and the twelfth lens is cemented to the thirteenth lens.

[0044] In one implementation, the total optical length of the zoom lens is TTL, the diameter of the first lens is D1, D1≤60.0 mm, and 0.382≤D1 / TTL≤0.496.

[0045] In one embodiment, the zoom lens further includes:

[0046] an aperture, wherein the aperture is disposed between the second lens group and the third lens group;

[0047] An imaging plane, located on the image side of the seventh lens group;

[0048] Wherein, the distance from the aperture to the imaging plane is L, the total optical length of the zoom lens is TTL, and 0.356≤L / TTL≤0.534.

[0049] The utility model also proposes a monitoring device, which includes a zoom lens, the zoom lens has an optical axis extending along a first direction, and has an object side and an image side relatively arranged in the first direction, the zoom lens includes a first lens group, a second lens group, a third lens group, a fourth lens group, a fifth lens group, a sixth lens group, and a seventh lens group arranged in sequence from the object side to the image side; the first lens group, the third lens group, the fifth lens group, and the seventh lens group have positive optical focal length; the second lens group, the fourth lens group, and the sixth lens group have negative optical focal length; wherein the second lens group, the fourth lens group, and the fifth lens group are movably arranged along the optical axis direction for zooming; the sixth lens group is movably arranged along the optical axis direction for focusing; the third lens group has a moving stroke for translation along a vertical first direction, and a rotating stroke for rotation around a rotation axis along the first direction.

[0050] The technical solution of the utility model adopts the method that the second lens group, the fourth lens group and the fifth lens group are movably arranged along the optical axis direction for zooming and adjusting the magnification; the sixth lens group is movably arranged along the optical axis direction for focusing to make the image clear; the third lens group has a moving stroke for translation along a vertical first direction and a rotating stroke around a rotation axis along the first direction, which is used to adjust the imaging position during shaking so that the image can fall on the imaging surface to form a clear image. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0052] Figure 1 A schematic structural diagram of an embodiment of a zoom lens provided by the utility model in a wide-angle state;

[0053] Figure 2 A schematic structural diagram of an embodiment of a zoom lens provided by the utility model in a telephoto state;

[0054] Figure 3 for Figure 1 The through-focus MTF graph of a medium zoom lens at 160lp / mm at wide angle;

[0055] Figure 4 for Figure 1 MTF-Field diagram of a medium zoom lens at wide angle;

[0056] Figure 5 for Figure 1 The through-focus MTF graph of a medium zoom lens at 120lp / mm at wide angle;

[0057] Figure 6 for Figure 1 Field curvature-distortion diagram of a medium zoom lens at wide angle;

[0058] Figure 7 for Figure 1 Light fan diagram of a medium zoom lens at wide angle;

[0059] Figure 8 for Figure 1 Axial aberration diagram of a medium zoom lens at wide angle;

[0060] Fig. 9 for Figure 1 Vertical axis chromatic aberration diagram of the medium zoom lens at wide angle;

[0061] Fig.10 for Figure 2 The through-focus MTF graph of a medium zoom lens at 160lp / mm in telephoto mode.

[0062] Fig.11 for Figure 2 MTF-Field diagram of a medium zoom lens in telephoto state;

[0063] Fig.12 for Figure 2 The through-focus MTF graph of a medium zoom lens at 120lp / mm in telephoto mode.

[0064] Fig.13 for Figure 2 Field curvature-distortion diagram of a medium zoom lens at telephoto position;

[0065] Fig.14 for Figure 2 Light fan diagram of a medium zoom lens in telephoto mode;

[0066] Fig.15 for Figure 2 Axial aberration diagram of a medium zoom lens at telephoto position;

[0067] Fig.16 for Figure 2 Vertical axis chromatic aberration diagram of a medium zoom lens in telephoto position.

[0068] Description of Figure Numbers:

[0069] 100. zoom lens; 1. first lens group; 11. first lens; 12. second lens; 13. third lens; 14. fourth lens; 2. second lens group; 21. fifth lens; 22. sixth lens; 23. seventh lens; 3. third lens group; 31. eighth lens; 32. ninth lens; 4. fourth lens group; 41. tenth lens; 5. fifth lens group; 51. eleventh lens; 52. twelfth lens; 53. thirteenth lens; 6. sixth lens group; 61. fourteenth lens; 7. seventh lens group; 71. fifteenth lens; 8. aperture; 9. imaging surface; 10. filter.

[0070] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0071] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0072] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0073] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0074] At the same time, most monitoring scenes are generally outdoors where there is jitter or certain interference in the working environment. Moreover, when the large-magnification zoom optical lens is at the telephoto end, due to the relatively small viewing angle of the monitoring equipment, various factors such as wind blowing or shaking when installed at high places make it difficult for the large-magnification zoom optical lens to maintain a stable working state, resulting in image jitter and difficulty in capturing the subject normally, affecting the normal use of the monitoring equipment. Therefore, the demand for the development of zoom optical lenses that have both large-magnification functions and anti-shake design has become increasingly strong.

[0075] The utility model provides a zoom lens.

[0076] See also Figure 1 In one embodiment of the utility model, the zoom lens 100 has an optical axis extending along a first direction, and has an object side and an image side arranged opposite to each other in the first direction. The zoom lens 100 includes a first lens group 1, a second lens group 2, a third lens group 3, a fourth lens group 4, a fifth lens group 5, a sixth lens group 6, and a seventh lens group 7 arranged in sequence from the object side to the image side; the first lens group 1, the third lens group 3, the fifth lens group 5, and the seventh lens group 7 have positive optical power; the second lens group 2, the fourth lens group 4, and the sixth lens group 6 have negative optical power; wherein the second lens group 2, the fourth lens group 4, and the fifth lens group 5 are movably arranged along the optical axis direction for zooming; the sixth lens group 6 is movably arranged along the optical axis direction for focusing; the third lens group 3 has a moving stroke of translation along the vertical first direction, and a rotation stroke of rotation around the rotation axis along the first direction.

[0077] The magnification of the zoom lens 100, that is, the degree of magnification or reduction of the image, is related to the focal length of the zoom lens 100. The shorter the focal length, the stronger the focusing ability of the zoom lens 100 on light, and the greater the magnification of the image. The magnification of the image is adjusted by changing the relative positions of the lens groups in the zoom lens 100. For example, in the zoom lens 100, by changing the position of the moving lens group, the continuous change of the focal length can be achieved, thereby achieving a zoom effect. Therefore, the technical solution of the utility model is through the object side and the image side that are relatively arranged along the optical axis direction. The zoom lens 100 includes a first lens group 1, a second lens group 2, a third lens group 3, a fourth lens group 4, a fifth lens group 5, a sixth lens group 6, and a seventh lens group 7 arranged in sequence from the object side to the image side, wherein the second lens group 2, the fourth lens group 4 and the fifth lens group 5 are movably arranged along the extension direction of the optical axis to achieve the zoom of the zoom lens 100. The clarity of the zoom lens 100 is affected by many factors, including the quality of the lens groups, the relative positions between the lens groups, and the overall design of the zoom lens 100. The focusing system of the zoom lens 100 can make the image clear by moving the lens groups so that the image is presented on the imaging surface 9. In order to achieve this function, the sixth lens group 6 is movably arranged along the optical axis direction to achieve the focusing of the zoom lens 100. In the zoom lens 100, the movement of the lens group is the key to achieving focal length change. When the focal length of the zoom lens 100 becomes shorter, the range of the captured picture becomes wider; and when the focal length of the zoom lens 100 becomes longer, the range of the captured picture becomes narrower, but the details are clearer. Therefore, the zoom lens 100 has two extreme states, namely the wide-angle state (such as Figure 1 As shown), telephoto state (as shown Figure 2 As shown). As well as the intermediate state adjusted between these two states, the position of the corresponding lens group can be adjusted according to the needs on site. In the zoom lens 100, the optical focal length of multiple lens groups is set to negative or positive in order to achieve specific optical effects and correct aberrations. The third lens group 3 has a moving stroke along a vertical first direction and a rotation stroke around a rotation axis along the first direction. When the zoom lens 100 shakes, the third lens group 3 changes its position with gravity to adjust the propagation direction of light so that the formed image still falls on the imaging surface 9, thereby ensuring clear imaging and achieving an anti-shake effect. In the design of the zoom lens 100, the optical focal length of the lens group is alternately set to negative and positive to achieve better optical performance, ensuring that light can enter the subsequent structure through the focusing lens group at a larger angle, and ensuring the wide-angle characteristics of the zoom lens 100. Therefore, the first lens group 1, the third lens group 3, the fifth lens group 5, and the seventh lens group 7 are set to be lens groups with positive optical power; and the second lens group 2, the fourth lens group 4, and the sixth lens group 6 are set to be lens groups with negative optical power.

[0078] In order to achieve a better anti-shake effect, the movable range of the moving stroke of the third lens group 3 is A31, which must satisfy: 0.2mm≥A31≥0mm; the rotation range of the rotation stroke is A32, which must satisfy: 0.2°≥A32≥-0.2°.

[0079] In order to make the zoom lens 100 have a larger magnification adjustment range, the zoom lens 100 needs to have an adjustable focal length range of: greater than or equal to 6.4 mm and less than or equal to 250 mm; and an adjustable aperture range of: greater than or equal to 1.69 and less than or equal to 4.92. Therefore, the corresponding lens group for the movable setting needs to meet the following requirements: the movable stroke of the second lens group 2 in the optical axis direction is A2, A2 ≥ 41.8mm; the movable stroke of the fourth lens group 4 in the optical axis direction is A4, A4 ≥ 4.2mm; the movable stroke of the fifth lens group 5 in the optical axis direction is A5, A5 ≥ 13.3mm; the movable stroke of the sixth lens group 6 in the optical axis direction is A6, A6 ≥ 20.3mm.

[0080] In order to ensure that the zoom lens 100 is compact, the total optical length of the zoom lens 100 is TTL, TTL≤139mm; in order to meet the requirements of a larger magnification, the movable stroke corresponding to each movable lens group must meet the following requirements: 0.262≤A2 / TTL≤0.340; 0.026≤A4 / TTL≤0.034; 0.083≤A5 / TTL≤0.108; 0.127≤A6 / TTL≤0.165.

[0081] For specific implementation, the focal length of the zoom lens 100 is adjustable within a range of greater than or equal to 6.4 mm and less than or equal to 250 mm. For an optical lens, different maximum aperture values ​​are provided at different focal lengths, and the range of aperture values ​​will also change. It is also necessary to make the aperture number of the zoom lens 100 adjustable within a range of greater than or equal to 1.69 and less than or equal to 4.92.In a specific embodiment, each lens group must meet the following requirements: the focal length F of the zoom lens in the wide-angle state is F=6.4 mm; the focal length of the first lens group is f1, 0.085≤F / f1≤0.115; the first lens group includes a first lens, a second lens, a third lens, and a fourth lens arranged in sequence from the object side to the image side; the focal length of the first lens is f11, -0.692≤f1 / f11≤-0.511; the focal length of the second lens is f12, 0.487≤f1 / f12≤0.659; the focal length of the third lens is f13, 0.387≤f1 / f13≤0.523; the focal length of the fourth lens is f14, 0.495≤f 1 / f14≤0.670; the focal length of the second lens group is f2, -0.720≤F / f2≤-0.532; the second lens group includes a fifth lens, a sixth lens, and a seventh lens arranged in sequence from the object side to the image side; the focal length of the fifth lens is f21, 0.519≤f2 / f21≤0.703; the focal length of the sixth lens is f22, 0.556≤f2 / f22≤0.753; the focal length of the seventh lens is f23, -0.414≤f2 / f23≤-0.306; the focal length of the third lens group is f3, 0.353≤F / f3≤0.478; the third lens group includes an eighth lens and a ninth lens; the eighth lens The focal length of the ninth lens is f32, 0.383≤f3 / f32≤0.518; the focal length of the fourth lens group is f4, -0.595≤F / f4≤-0.440; the fourth lens group includes a tenth lens; the focal length of the tenth lens is f41, 0.850≤f4 / f41≤1.150; the focal length of the fifth lens group is f5, 0.309≤F / f5≤0.418; the fifth lens group includes an eleventh lens, a twelfth lens, and a thirteenth lens arranged in sequence from the object side to the image side; the focal length of the eleventh lens is f51, 0.830≤f5 / f51≤ 1.123; the focal length of the twelfth lens is f52, -1.148≤f5 / f52≤-0.849; the focal length of the thirteenth lens is f53, 0.882≤f5 / f53≤1.194; the focal length of the sixth lens group is f6, -0.325≤F / f6≤-0.276; the sixth lens group includes a fourteenth lens; the focal length of the fourteenth lens is f61, 0.850≤f6 / f61≤1.150; the focal length of the seventh lens group is f7, 0.196≤F / f7≤0.265; the seventh lens group includes a fifteenth lens; the focal length of the fifteenth lens is f71, 0.850≤f7 / f71≤1.150.

[0082] The wide-angle state of the zoom lens 100 in the present invention (eg Figure 1 As shown), the imaging surface 9 has a size of Φ9.3 mm, a focal length of 6.4 mm, a distortion degree of less than or equal to -2.90%, and an applicable wavelength range of 436 mm to 870 mm; the telephoto state of the zoom lens 100 (as shown Figure 2 As shown), the imaging surface 9 has a size of Φ9.3mm, a focal length of 250mm, a distortion degree of less than or equal to -2.15%, and an applicable band of 436mm-870mm.

[0083] In a specific embodiment, the focal length parameters of each component are as follows (unit: mm):

[0084]

[0085]

[0086] In the zoom lens 100, spherical lenses and aspherical lenses are usually used in combination. Spherical lenses can be used as basic elements for preliminary correction of aberrations, while aspherical lenses are used for fine adjustment to achieve higher optical performance. Through this combination, lens designers can maximize the imaging quality of the lens while maintaining cost-effectiveness. In summary, different types of lenses are used in the zoom lens 100 to balance cost, manufacturing complexity and optical performance. Spherical lenses provide basic optical functions, while aspherical lenses are used to improve and optimize these functions to achieve high-quality imaging effects together. In one embodiment, the first lens 11, the second lens 12, the third lens 13, the fourth lens 14, the sixth lens 22, the seventh lens 23, the ninth lens 32, the twelfth lens 52, and the thirteenth lens 53 are all set as spherical lenses; the fifth lens 21, the eighth lens 31, the tenth lens 41, the eleventh lens 51, the fourteenth lens 61, and the fifteenth lens 71 are all set as aspherical lenses. Aspherical lenses are placed near the object side to reduce common distortions in wide-angle lenses, such as barrel distortion, making the image more realistic. They are placed near the image side to help improve the imaging quality of telephoto lenses, especially in areas far from the optical center. Aspherical lenses are used at specific zoom positions to compensate for specific aberrations that occur at that position.

[0087] In a specific embodiment:

[0088]

[0089]

[0090]

[0091]

[0092] Specifically, the surface shape of each aspheric lens can be defined by but not limited to the following aspheric formula:

[0093]

[0094] Among them, c is the curvature corresponding to the radius, y is the radial coordinate (its unit is the same as the lens length unit), k is the coefficient of the conic quadratic curve (when the k coefficient is less than -1, the surface curve is a hyperbola, when the k coefficient is equal to -1, it is a parabola, when the k coefficient is between -1 and 0, it is an ellipse, when the k coefficient is equal to 0, it is a circle, and when the k coefficient is greater than 0, it is an oblate circle), A, B, C, D, E, F are high-order aspheric coefficients, and the high-order coefficients of each aspheric mirror surface can be seen from the above table.

[0095] In order to optimize the optical performance of the lens, reduce aberrations, improve the imaging quality, simplify the manufacturing process and reduce costs. In one embodiment, the first lens 11 is bonded with the second lens 12, the sixth lens 22 is bonded with the seventh lens 23, and the twelfth lens 52 is bonded with the thirteenth lens 53. The reason why the optical performance of the lens can be optimized, the aberration can be reduced, the imaging quality can be improved, the manufacturing process can be simplified and the cost can be reduced is that lenses of different materials will produce different degrees of refraction when passing through light of different colors, resulting in chromatic aberration. By bonding two or more lenses of different materials together, the chromatic aberration can be offset to obtain a clearer color image. When a single lens contacts the air, there will be a large reflection loss, while the reflection loss between the bonded lens and the glass is greatly reduced, thereby improving the transmission efficiency of light energy and increasing the brightness of the image. Bonding can compensate for the slight differences between the lenses, reduce the requirements for precision processing, and simplify the optical design. This helps to reduce manufacturing costs while maintaining high-quality imaging performance. The sealing layer formed during the bonding process can protect the surface of the optical parts, prevent the intrusion of dust and other particles, and extend the service life of the lens. Cemented lenses can combine two or more lenses into a single optical unit, which can reduce the spacing between lenses and improve optical performance, such as reducing spherical aberration and coma.

[0096] The ratio of the distance from the aperture 8 to the imaging plane 9 to the total length affects the design flexibility and imaging performance of the lens. A smaller ratio means that the optical part of the lens occupies most of the total length, which may help to achieve a more compact design, but may also limit the focal length range and field of view of the lens. On the contrary, a larger ratio may mean that the optical part of the lens is shorter and the mechanical part is longer, which may allow a larger focal length range and a more flexible design, but may also result in a larger overall size of the lens. For the zoom lens 100 proposed in the utility model, the aperture 8 is arranged between the second lens group 2 and the third lens group 3; and the imaging plane 9 is located on the image side of the seventh lens group 7; wherein the distance from the aperture 8 to the imaging plane 9 is L, 0.356≤L / TTL≤0.534. In order to meet the lens volume requirements, the corresponding optical total length of the zoom lens 100 is TTL, and the diameter of the first lens 11 is D1, which needs to satisfy D1≤60.0mm and 0.382≤D1 / TTL≤0.496.

[0097] The utility model also proposes a monitoring device, which includes a zoom lens 100. The specific structure of the zoom lens 100 refers to the above embodiment. Since the monitoring device adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here one by one. Wherein, the monitoring device includes a zoom lens 100, the zoom lens 100 has an optical axis extending along a first direction, and has an object side and an image side relatively arranged in the first direction, the zoom lens 100 includes a first lens group 1, a second lens group 2, a third lens group 3, a fourth lens group 4, a fifth lens group 5, a sixth lens group 6, and a seventh lens group 7 arranged in sequence from the object side to the image side; the first lens group 1, the third lens group 3, the fifth lens group 5, and the seventh lens group 7 have positive optical power; the second lens group 2, the fourth lens group 4, and the sixth lens group 6 have negative optical power; wherein, the second lens group 2, the fourth lens group 4, and the fifth lens group 5 are movably arranged along the optical axis direction for zooming; the sixth lens group 6 is movably arranged along the optical axis direction for focusing; the third lens group 3 has a moving stroke of translation along a vertical first direction, and a rotation stroke of rotation around a rotation axis along the first direction.

[0098] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A zoom lens, characterized in that: The zoom lens has an optical axis extending along a first direction, and has an object side and an image side arranged opposite to each other in the first direction, and comprises a first lens group, a second lens group, a third lens group, a fourth lens group, a fifth lens group, a sixth lens group, and a seventh lens group arranged in sequence from the object side to the image side; The first lens group, the third lens group, the fifth lens group, and the seventh lens group have positive refractive power; The second lens group, the fourth lens group and the sixth lens group have negative optical power; Wherein, the second lens group, the fourth lens group, and the fifth lens group are movably arranged along the optical axis direction for zooming; The sixth lens group is movably arranged along the optical axis direction for focusing; the third lens group has a moving stroke of translation along a vertical first direction and a rotating stroke around a rotation axis along the first direction.

2. The zoom lens according to claim 1, wherein: The movable range of the moving stroke is A31, 0.2mm≥A31≥0mm; The rotation range of the rotation stroke is A32, 0.2°≥A32≥-0.2°.

3. The zoom lens according to claim 1, wherein: The movable stroke of the second lens group in the optical axis direction is A2, A2 ≥ 41.8 mm; The movable stroke of the fourth lens group in the optical axis direction is A4, A4≥4.2mm; The movable stroke of the fifth lens group in the optical axis direction is A5, A5≥13.3mm; The movable stroke of the sixth lens group in the optical axis direction is A6, A6≥20.3mm The zoom lens has an adjustable focal length range of greater than or equal to 6.4 mm and less than or equal to 250 mm; and an adjustable aperture number range of greater than or equal to 1.69 and less than or equal to 4.

92.

4. The zoom lens according to claim 3, wherein: The total optical length of the zoom lens is TTL, TTL≤139mm; and meets the following requirements: 0.262≤A2 / TTL≤0.340; 0.026≤A4 / TTL≤0.034; 0.083≤A5 / TTL≤0.108; 0.127≤A6 / TTL≤0.

165.

5. The zoom lens according to claim 1, wherein: The focal length of the zoom lens is adjustable within a range of greater than or equal to 6.4 mm and less than or equal to 250 mm. In a wide-angle state, the focal length F of the zoom lens is F=6.4 mm; The focal length of the first lens group is f1, 0.085≤F / f1≤0.115; the first lens group includes a first lens, a second lens, a third lens, and a fourth lens arranged in sequence from the object side to the image side; The focal length of the first lens is f11, -0.692≤f1 / f11≤-0.511; The focal length of the second lens is f12, 0.487≤f1 / f12≤0.659; The focal length of the third lens is f13, 0.387≤f1 / f13≤0.523; The focal length of the fourth lens is f14, 0.495≤f1 / f14≤0.670; The focal length of the second lens group is f2, -0.720≤F / f2≤-0.532; The second lens group includes a fifth lens, a sixth lens, and a seventh lens arranged in sequence from the object side to the image side; The focal length of the fifth lens is f21, 0.519≤f2 / f21≤0.703; The focal length of the sixth lens is f22, 0.556≤f2 / f22≤0.753; The focal length of the seventh lens is f23, -0.414≤f2 / f23≤-0.306; The focal length of the third lens group is f3, 0.353≤F / f3≤0.478; The third lens group includes an eighth lens and a ninth lens; The focal length of the eighth lens is f31, 0.518≤f3 / f31≤0.701; The focal length of the ninth lens is f32, 0.383≤f3 / f32≤0.518; The focal length of the fourth lens group is f4, -0.595≤F / f4≤-0.440; the fourth lens group includes a tenth lens; The focal length of the tenth lens is f41, 0.850≤f4 / f41≤1.150; The focal length of the fifth lens group is f5, 0.309≤F / f5≤0.418; The fifth lens group includes an eleventh lens, a twelfth lens, and a thirteenth lens arranged in sequence from the object side to the image side; The focal length of the eleventh lens is f51, 0.830≤f5 / f51≤1.123; The focal length of the twelfth lens is f52, -1.148≤f5 / f52≤-0.849; The focal length of the thirteenth lens is f53, 0.882≤f5 / f53≤1.194; The focal length of the sixth lens group is f6, -0.325≤F / f6≤-0.276; the sixth lens group includes a fourteenth lens; The focal length of the fourteenth lens is f61, 0.850≤f6 / f61≤1.150; The focal length of the seventh lens group is f7, 0.196≤F / f7≤0.265; the seventh lens group includes a fifteenth lens; The focal length of the fifteenth lens is f71, 0.850≤f7 / f71≤1.

150.

6. The zoom lens according to claim 5, wherein: The first lens, the second lens, the third lens, the fourth lens, the sixth lens, the seventh lens, the ninth lens, the twelfth lens, and the thirteenth lens are all configured as spherical lenses; The fifth lens, the eighth lens, the tenth lens, the eleventh lens, the fourteenth lens, and the fifteenth lens are all configured as aspherical lenses.

7. The zoom lens according to claim 5, wherein: The first lens is glued to the second lens, the sixth lens is glued to the seventh lens, and the twelfth lens is glued to the thirteenth lens.

8. The zoom lens according to claim 5, wherein: The total optical length of the zoom lens is TTL, the diameter of the first lens is D1, D1≤60.0 mm, and 0.382≤D1 / TTL≤0.

496.

9. The zoom lens according to claim 1, wherein: The zoom lens further comprises: an aperture, wherein the aperture is disposed between the second lens group and the third lens group; An imaging plane, located on the image side of the seventh lens group; Wherein, the distance from the aperture to the imaging plane is L, the total optical length of the zoom lens is TTL, and 0.356≤L / TTL≤0.

534.

10. A monitoring device, characterized in that: The invention comprises a zoom lens as claimed in any one of claims 1 to 9.

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