Zoom lens

Abstract

The embodiment of the utility model discloses a zoom lens. The zoom lens comprises a first fixed lens group, a first zoom lens group, a diaphragm, a second zoom lens group, a focusing lens group and a second fixed lens group which are sequentially arranged from an object space to an image space along an optical axis, wherein the focal powers are positive, negative, positive and negative in sequence; wherein the first fixed lens group comprises four lenses, and the focal powers of the four lenses are negative, positive, positive and positive in sequence; the first zoom lens group comprises three lenses, and the focal power of the three lenses is negative, negative and positive in sequence; the second zoom lens group comprises four lenses of which the focal powers are positive, positive, negative and positive in sequence; the focusing lens group comprises two lenses, and the focal power of the two lenses is positive and negative in sequence; the second fixed lens group comprises two lenses, and the focal power of the two lenses is positive and negative in sequence. According to the embodiment of the utility model, 15 lenses and plate glass with a certain thickness are used, and the five-component zoom lens can be adapted to a 1 / 1.8 ''target surface, so that the five-component zoom lens has the advantages of large multiplying power, large aperture, small distortion and high image quality.

Description

Technical Field

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

[0002] In the security field, zoom lenses have been widely used due to their advantages of long shooting distance, continuous and rapid zooming, and the ability to achieve good shooting effects in different usage scenarios. However, with the development of technology, cameras are gradually moving towards miniaturization and refinement, which also puts forward more stringent requirements for mainstream zoom lenses.

[0003] At present, 1 / 1.8” chips are gradually becoming the mainstream chips on the market and have been more widely used. However, traditional zoom lenses usually use 1 / 2.7” chips, which are difficult to use in a wide range of environments. Traditional zoom lenses also have problems such as small aperture. Therefore, it is necessary to develop a lens with a large magnification, large aperture, small distortion, and all-glass. Utility Model Content

[0004] The utility model provides a zoom lens to adapt to the 1 / 1.8" target surface and realize the optical characteristics of large magnification, large aperture, small distortion and high image quality.

[0005] The embodiment of the utility model provides a zoom lens, comprising a first fixed lens group with positive optical power, a first zoom lens group with negative optical power, an aperture, a second zoom lens group with positive optical power, a focus lens group with positive optical power, and a second fixed lens group with negative optical power, which are arranged in sequence from the object side to the image side along the optical axis;

[0006] The first fixed lens group includes a first lens with negative optical power, a second lens with positive optical power, a third lens with positive optical power, and a fourth lens with positive optical power;

[0007] The first zoom lens group includes a fifth lens with negative optical power, a sixth lens with negative optical power, and a seventh lens with positive optical power;

[0008] The second zoom lens group includes an eighth lens with positive optical power, a ninth lens with positive optical power, a tenth lens with negative optical power, and an eleventh lens with positive optical power;

[0009] The focusing lens group includes a twelfth lens having a positive optical power and a thirteenth lens having a negative optical power;

[0010] The second fixed lens group includes a fourteenth lens having a positive optical power and a fifteenth lens having a negative optical power;

[0011] During the zooming process, the positions of the first fixed lens group and the second fixed lens group are fixed, the first zoom lens group and the second zoom lens group move along the optical axis to zoom, and the focus lens group moves along the optical axis to focus.

[0012] Optionally, the focal power G1 of the first fixed lens group, the focal power G2 of the first variator group, the focal power G3 of the second variator group, the focal power G4 of the focus lens group, the focal power G5 of the second fixed lens group and the wide-angle end focal length FW of the zoom lens satisfy the following condition:

[0013] 7.924≤|G1 / FW|≤8.377;

[0014] 1.503≤|G2 / FW|≤1.657;

[0015] 4.327≤|G3 / FW|≤9.343;

[0016] 3.916≤|G4 / FW|≤4.333;

[0017] 9.151≤|G5 / FW|≤71.320.

[0018] Optionally, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the twelfth lens, the thirteenth lens and the fourteenth lens are all glass spherical lenses;

[0019] The sixth lens, the eleventh lens and the fifteenth lens are glass aspherical lenses.

[0020] Optionally, the refractive index Nd1 and the Abbe number Vd1 of the sixth lens, the refractive index Nd2 and the Abbe number Vd2 of the eleventh lens, and the refractive index Nd3 and the Abbe number Vd3 of the fifteenth lens satisfy the following conditions:

[0021] 1.45≤Nd1≤1.55;50.00≤Vd1≤95.00;

[0022] 1.45≤Nd2≤1.55;74.00≤Vd2≤95.00;

[0023] 1.45≤Nd3≤1.80;63.00≤Vd3≤95.00.

[0024] Optionally, the object side surface of the first lens is convex, the object side and image side surfaces of the second lens are convex-convex, the object side and image side surfaces of the third lens are convex-convex, and the object side and image side surfaces of the fourth lens are convex-concave;

[0025] The object side and image side surfaces of the fifth lens are convex-concave, the object side and image side surfaces of the sixth lens are concave-concave, and the object side and image side surfaces of the seventh lens are convex-convex;

[0026] The object side and image side surfaces of the eighth lens are convex-convex, the object side surface of the ninth lens is convex, the object side and image side surfaces of the tenth lens are concave-concave, and the object side and image side surfaces of the eleventh lens are convex-concave;

[0027] The object side surface of the twelfth lens is convex, and the object side and image side surfaces of the thirteenth lens are concave-convex;

[0028] The object side and image side surfaces of the fourteenth lens are concave-convex, and the object side and image side surfaces of the fifteenth lens are concave-convex.

[0029] Optionally, the first lens and the second lens are glued together to form a first glued lens group;

[0030] The ninth lens and the tenth lens are cemented together to form a second cemented lens group;

[0031] The twelfth lens and the thirteenth lens are cemented together to form a third cemented lens group.

[0032] Optionally, the focal length f8 of the first cemented lens group and the focal length FW at the wide-angle end of the zoom lens satisfy the following condition: 56.464≤f8 / FW≤60.887.

[0033] Optionally, the focal length f1 of the fifth lens, the focal length f2 of the sixth lens, the focal length f3 of the seventh lens, and the wide-angle end focal length FW of the zoom lens satisfy the following condition:

[0034] 1.817≤|f1 / FW|≤2.002;

[0035] 3.450≤|f2 / FW|≤3.942;

[0036] 4.905≤|f3 / FW|≤5.645;

[0037] The focal length f4 of the eighth lens, the focal length f5 of the ninth lens, the focal length f6 of the tenth lens, the focal length f7 of the eleventh lens and the focal length FW at the wide-angle end of the zoom lens satisfy the following condition:

[0038] 4.349≤|f4 / FW|≤4.684;

[0039] 3.643≤|f5 / FW|≤3.882;

[0040] 1.647≤|f6 / FW|≤1.709;

[0041] 4.016≤|f7 / FW|≤4.220.

[0042] Optionally, the focal length FW at the wide-angle end of the zoom lens and the optical distortion DIS satisfy the following condition: 0.292<|DIS / FW|<1.881.

[0043] Optionally, the movable distance of the first zoom lens group on the optical axis is ZOL1 and the total optical system length TTL of the zoom lens satisfies the following condition: 0.282≤ZOL1 / TTL≤0.337;

[0044] The movable distance of the second zoom lens group on the optical axis is ZOL2 and the total length of the optical system of the zoom lens is TTL, which satisfies the following condition: 0.107≤ZOL2 / TTL≤0.125.

[0045] Optionally, the image plane size HI of the zoom lens and the total length TTL of the optical system satisfy the following condition: 0.070≤HI / TTLT≤0.082.

[0046] The zoom lens provided by the embodiment of the utility model is provided with a first fixed lens group, a first variator group, an aperture, a second variator group, a focus lens group, and a second fixed lens group, and the optical power is positive, negative, positive, positive, and negative in sequence; wherein the first fixed lens group includes four lenses, and the optical power is negative, positive, positive, and positive in sequence; the first variator group includes three lenses, and the optical power is negative, negative, and positive in sequence; the second variator group includes four lenses, and the optical power is positive, positive, negative, and positive in sequence; the focus lens group includes two lenses, and the optical power is positive and negative in sequence; the second fixed lens group includes two lenses, and the optical power is positive and negative in sequence; the first variator group and the second variator group move along the optical axis to zoom, while the focus lens group moves along the optical axis to compensate for aberrations, thereby achieving clear imaging. The embodiment of the utility model uses 15 lenses and a certain thickness of flat glass, which can be adapted to a 1 / 1.8″ target surface, thereby realizing a five-element zoom lens with the advantages of large magnification, large aperture, small distortion, and high image quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a schematic structural diagram of a zoom lens at the wide-angle end provided by Embodiment 1 of the present utility model;

[0048] Figure 2 yes Figure 1 The structure diagram of the zoom lens at the telephoto end is shown;

[0049] Figure 3 yes Figure 1 and Figure 2 The field curvature distortion diagram of the zoom lens at the wide-angle end is shown;

[0050] Figure 4 yes Figure 1 and Figure 2 The light fan diagram of the zoom lens at the wide-angle end is shown;

[0051] Figure 5 yes Figure 1 and Figure 2 The vertical axis chromatic aberration diagram of the zoom lens at the wide angle end is shown;

[0052] Figure 6 yes Figure 1 and Figure 2 Axial aberration diagram of the zoom lens at the wide-angle end shown;

[0053] Figure 7 yes Figure 1 and Figure 2 The field curvature distortion diagram of the zoom lens at the telephoto end is shown;

[0054] Figure 8 yes Figure 1 and Figure 2 The light fan diagram of the zoom lens at the telephoto end is shown;

[0055] Fig. 9 yes Figure 1 and Figure 2 The vertical axis chromatic aberration diagram of the zoom lens at the telephoto end is shown;

[0056] Fig.10 yes Figure 1 and Figure 2 Axial aberration diagram of the zoom lens at the telephoto end shown;

[0057] Fig.11 This is a schematic structural diagram of a zoom lens at the wide-angle end provided by Embodiment 2 of the present utility model;

[0058] Fig.12 yes Fig.11 The structure diagram of the zoom lens at the telephoto end is shown;

[0059] Fig.13 yes Fig.11 and Fig.12 The field curvature distortion diagram of the zoom lens at the wide-angle end is shown;

[0060] Fig.14yes Fig.11 and Fig.12 The light fan diagram of the zoom lens at the wide-angle end is shown;

[0061] Fig.15 yes Fig.11 and Fig.12 The vertical axis chromatic aberration diagram of the zoom lens at the wide angle end is shown;

[0062] Fig.16 yes Fig.11 and Fig.12 Axial aberration diagram of the zoom lens at the wide-angle end shown;

[0063] Fig.17 yes Fig.11 and Fig.12 The field curvature distortion diagram of the zoom lens at the telephoto end is shown;

[0064] Fig.18 yes Fig.11 and Fig.12 The light fan diagram of the zoom lens at the telephoto end is shown;

[0065] Fig.19 yes Fig.11 and Fig.12 The vertical axis chromatic aberration diagram of the zoom lens at the telephoto end is shown;

[0066] Fig. 20 yes Fig.11 and Fig.12 Axial aberration diagram of the zoom lens at the telephoto end shown;

[0067] Fig.21 This is a schematic structural diagram of a zoom lens at the wide-angle end provided by Embodiment 3 of the present utility model;

[0068] Fig. 22 yes Fig.21 The structure diagram of the zoom lens at the telephoto end is shown;

[0069] Fig.23 yes Fig.21 and Fig. 22 The field curvature distortion diagram of the zoom lens at the wide-angle end is shown;

[0070] Fig.24 yes Fig.21 and Fig. 22 The light fan diagram of the zoom lens at the wide-angle end is shown;

[0071] Fig.25 yes Fig.21 and Fig. 22 The vertical axis chromatic aberration diagram of the zoom lens at the wide angle end is shown;

[0072] Fig.26 yes Fig.21 and Fig. 22 Axial aberration diagram of the zoom lens at the wide-angle end shown;

[0073] Fig. 27 yes Fig.21 and Fig. 22 The field curvature distortion diagram of the zoom lens at the telephoto end is shown;

[0074] Fig.28 yes Fig.11 and Fig.12 The light fan diagram of the zoom lens at the telephoto end is shown;

[0075] Fig.29 yes Fig.21 and Fig. 22 The vertical axis chromatic aberration diagram of the zoom lens at the telephoto end is shown;

[0076] Fig.30 yes Fig.21 and Fig. 22 Axial aberration diagram of the zoom lens at the telephoto end. DETAILED DESCRIPTION

[0077] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0078] Figure 1 1 is a schematic diagram of the structure of a zoom lens at the wide-angle end provided by the first embodiment of the utility model. Figure 2 yes Figure 1 The structure diagram of the zoom lens at the telephoto end is shown in FIG. Figure 1 and Figure 2 The zoom lens comprises a first fixed lens group 100 with positive focal power, a first zoom lens group 200 with negative focal power, an aperture 600, a second zoom lens group 300 with positive focal power, a focus lens group 400 with positive focal power, and a second fixed lens group 500 with negative focal power, which are arranged in sequence from the object side to the image side along the optical axis;

[0079] The first fixed lens group 100 includes a first lens 101 with negative optical power, a second lens 102 with positive optical power, a third lens 103 with positive optical power, and a fourth lens 104 with positive optical power;

[0080] The first zoom lens group 200 includes a fifth lens 205 with negative optical power, a sixth lens 206 with negative optical power, and a seventh lens 207 with positive optical power;

[0081] The second zoom lens group 300 includes an eighth lens 308 with positive optical power, a ninth lens 309 with positive optical power, a tenth lens 310 with negative optical power, and an eleventh lens 311 with positive optical power;

[0082] The focusing lens group 400 includes a twelfth lens 412 with positive optical power and a thirteenth lens 413 with negative optical power;

[0083] The second fixed lens group 500 includes a fourteenth lens 514 with positive optical power and a fifteenth lens 515 with negative optical power;

[0084] During the zooming process, the positions of the first fixed lens group 100 and the second fixed lens group 500 are fixed, the first zoom lens group 200 and the second zoom lens group 300 move along the optical axis to zoom, and the focus lens group 400 moves along the optical axis to focus.

[0085] First of all, it can be understood that the focal power is equal to the difference between the convergence of the image-side beam and the convergence of the object-side beam, and it characterizes the ability of the optical system to deflect light. The larger the absolute value of the focal power, the stronger the ability to bend light, and the smaller the absolute value of the focal power, the weaker the ability to bend light. When the focal power is a positive number, the refraction of light is convergent; when the focal power is a negative number, the refraction of light is divergent. The focal power can be used to characterize a certain refractive surface of a lens (i.e., a surface of a lens), can be used to characterize a certain lens or lens group, and can also be used to characterize a system composed of multiple lenses (i.e., a group or lens group). In this embodiment, the first fixed lens group 100, the first variator group 200, the second variator group 300, the focus lens group 400, and the second fixed lens group 500 can be arranged in a lens barrel, the first fixed lens group 100 and the second fixed lens group 500 are fixed in the lens barrel, and the first variator group 200, the second variator group 300, and the focus lens group 400 can reciprocate along the optical axis in the lens barrel. The first variator group 200 and the second variator group 300 are used to adjust the focal length of the lens by moving, so as to change the focal length of the zoom lens, and the focus lens group 400 is used to compensate for aberrations caused by the movement of the first variator group 200 and the second variator group 300. It can be understood that, in the process of zooming by moving the corresponding groups, the zoom lens is located at the wide-angle end when the focal length is shortest, and is located at the telephoto end when the focal length is longest. At the wide-angle end and the telephoto end, the zoom lens has different focal lengths and optical powers, and also has different lengths or shapes.

[0086] In this embodiment, by setting the focal length of the first fixed lens group 100 to be positive and the focal length of the first zoom lens group 200 to be negative, it is ensured that the light can enter the subsequent structure through the first fixed lens group 100. At the same time, the focal lengths of the first fixed lens group 100, the first zoom lens group 200, the second zoom lens group 300, the focus lens group 400 and the second fixed lens group 500 are positive, negative, positive, positive, and negative in sequence. By using this combination of focal lengths, it is ensured that the light does not produce a sudden change and passes through the lens smoothly, while achieving a longer focal length. In addition, the diaphragm 600 is set between the first zoom lens group 200 and the second zoom lens group 300, in order to control the high-order aberrations of the lens in the front half of the lens, ensure that the image height can be increased and the target surface can be expanded in the rear half of the lens, and at the same time, achieve good image quality to meet the use requirements in more situations.

[0087] In addition, the first fixed lens group 100 includes three lenses whose optical powers are negative, positive and positive, respectively; the first zoom lens group 200 includes three lenses whose optical powers are negative, negative and positive, respectively; the second zoom lens group 300 includes four lenses whose optical powers are positive, positive, negative and positive, respectively; the focusing lens group 400 includes two lenses whose optical powers are positive and negative, respectively; the second fixed lens group 500 includes two lenses whose optical powers are positive and negative, respectively; and each lens can be connected with each other through a Mylar sheet or a spacer. Through the coordination of the lenses with different optical powers, on the one hand, the role of each lens in the group to which it belongs can be limited, the coordination of the lenses in each group can be ensured, and the role of the group can be realized; on the other hand, the zoom function or compensation function of the group can be adjusted through the material and the surface shape on the basis of ensuring that the lens has the limited optical power, thereby helping to improve the imaging quality of the zoom lens.

[0088] It should be added that the zoom lens of the present invention is also provided with a flat glass 700; the flat glass 700 is located on one side of the image side surface of the fifteenth lens 515, and the flat glass 700 can protect the photosensitive chip (not shown in the figure) in the imaging sensor located on the image plane. The photosensitive chip is used to convert the light signal collected by the zoom lens into an electrical signal, thereby realizing the imaging of the zoom lens.

[0089] The zoom lens provided by the embodiment of the utility model is provided with a first fixed lens group, a first variator group, an aperture, a second variator group, a focus lens group, and a second fixed lens group, and the optical power is positive, negative, positive, positive, and negative in sequence; wherein the first fixed lens group includes four lenses, and the optical power is negative, positive, positive, and positive in sequence; the first variator group includes three lenses, and the optical power is negative, negative, and positive in sequence; the second variator group includes four lenses, and the optical power is positive, positive, negative, and positive in sequence; the focus lens group includes two lenses, and the optical power is positive and negative in sequence; the second fixed lens group includes two lenses, and the optical power is positive and negative in sequence; the first variator group and the second variator group move along the optical axis to zoom, while the focus lens group moves along the optical axis to compensate for aberrations, thereby achieving clear imaging. The embodiment of the utility model uses 15 lenses and a certain thickness of flat glass, which can be adapted to a 1 / 1.8″ target surface, thereby realizing a five-element zoom lens with the advantages of large magnification, large aperture, small distortion, and high image quality.

[0090] In a specific embodiment, optionally, the optical power G1 of the first fixed lens group 100, the optical power G2 of the first variator group 200, the optical power G3 of the second variator group 300, the optical power G4 of the focus lens group 400, the optical power G5 of the second fixed lens group 500 and the wide-angle end focal length FW of the zoom lens meet the following conditions:

[0091] 7.924≤|G1 / FW|≤8.377;

[0092] 1.503≤|G2 / FW|≤1.657;

[0093] 4.327≤|G3 / FW|≤9.343;

[0094] 3.916≤|G4 / FW|≤4.333;

[0095] 9.151≤|G5 / FW|≤71.320.

[0096] In this specific embodiment, by setting the optical focal length of the five groups and the focal length of the wide-angle end of the zoom lens to meet the above conditions, a more refined and reasonable combination of optical focal lengths is achieved on the basis of satisfying the positive-negative-positive-positive-negative optical focal length combination, so that light can pass through the lens more smoothly, and at the same time can correct the high-order aberrations of the lens to a great extent, thereby improving the imaging quality.

[0097] In a specific embodiment, optionally, the first lens 101, the second lens 102, the third lens 103, the fourth lens 104, the fifth lens 205, the seventh lens 207, the eighth lens 308, the ninth lens 309, the tenth lens 310, the twelfth lens 412, the thirteenth lens 413 and the fourteenth lens 514 are all glass spherical lenses; the sixth lens 206, the eleventh lens 311 and the fifteenth lens 515 are glass aspherical lenses.

[0098] In this specific embodiment, a total of fifteen lenses in each group are glass lenses, realizing an all-glass zoom lens. By utilizing the characteristics of glass material, the sensitivity of imaging to temperature can be reduced, the degree of deformation of the lens at different temperatures can be reduced, and clear imaging can still be achieved in high and low temperature environments, thereby increasing the applicable scenarios of the zoom lens. At the same time, the sixth lens 206, the eleventh lens 311, and the fifteenth lens 515 are set to be aspherical lenses, which can be used to correct the geometric aberration of the lens, improve the resolution, and improve the image quality.

[0099] Further optionally, the refractive index Nd1 and the Abbe number Vd1 of the sixth lens 206, the refractive index Nd2 and the Abbe number Vd2 of the eleventh lens 311, and the refractive index Nd3 and the Abbe number Vd3 of the fifteenth lens 515 satisfy the following conditions:

[0100] 1.45≤Nd1≤1.55;50.00≤Vd1≤95.00;

[0101] 1.45≤Nd2≤1.55;74.00≤Vd2≤95.00;

[0102] 1.45≤Nd3≤1.80;63.00≤Vd3≤95.00.

[0103] At this time, based on the fact that the aspherical sixth lens 206, the eleventh lens 311 and the fifteenth lens 515 generally have a good corrective effect on the geometric aberration of the lens, when the above-mentioned refractive index and Abbe number requirements are met at the same time, it is beneficial to eliminate the distortion in the telephoto end image, compress the volume of the lens, and at the same time can correct spherical aberration and higher-order aberrations to a great extent.

[0104] More specifically, in one embodiment, the object-side surface of the first lens 101 is convex, the object-side and image-side surfaces of the second lens 102 are convex-convex, the object-side and image-side surfaces of the third lens 103 are convex-convex, and the object-side and image-side surfaces of the fourth lens 104 are convex-concave;

[0105] The object side and image side surfaces of the fifth lens 205 are convex-concave, the object side and image side surfaces of the sixth lens 206 are concave-concave, and the object side and image side surfaces of the seventh lens 207 are convex-convex;

[0106] The object-side and image-side surfaces of the eighth lens 308 are convex-convex, the object-side surface of the ninth lens 309 is convex, the object-side and image-side surfaces of the tenth lens 310 are concave-concave, and the object-side and image-side surfaces of the eleventh lens 311 are convex-concave;

[0107] The object-side surface of the twelfth lens 412 is convex, and the object-side and image-side surfaces of the thirteenth lens 413 are concave-convex;

[0108] The object-side and image-side surfaces of the fourteenth lens 514 are concave-convex, and the object-side and image-side surfaces of the fifteenth lens 515 are concave-convex.

[0109] In one embodiment, optionally, the first lens 101 and the second lens 102 are cemented to form a first cemented lens group; the ninth lens 309 and the tenth lens 310 are cemented to form a second cemented lens group; the twelfth lens 412 and the thirteenth lens 413 are cemented to form a third cemented lens group.

[0110] Gluing the adjacent partial lenses mentioned above to form a lens group can reduce the distance between lenses, properly correct chromatic aberration, and improve field curvature and coma, thereby further optimizing the imaging quality.

[0111] Further optionally, the focal length f8 of the first cemented lens group and the focal length FW at the wide-angle end of the zoom lens satisfy the following condition: 56.464≤f8 / FW≤60.887.

[0112] In this embodiment, the first lens 101 and the second lens 102 substantially form a convex front and convex back cemented lens group. On this basis, the focal length of the cemented lens group satisfies the above conditions, so that the object side light can be smoothly collected into the imaging system, and high-order aberrations can be corrected to a great extent.

[0113] In a specific embodiment, optionally, the focal length f1 of the fifth lens 205, the focal length f2 of the sixth lens 206, the focal length f3 of the seventh lens 207 and the focal length FW at the wide-angle end of the zoom lens satisfy the following condition:

[0114] 1.817≤|f1 / FW|≤2.002;

[0115] 3.450≤|f2 / FW|≤3.942;

[0116] 4.905≤|f3 / FW|≤5.645;

[0117] The focal length f4 of the eighth lens 308, the focal length f5 of the ninth lens 309, the focal length f6 of the tenth lens 310, the focal length f7 of the eleventh lens 311 and the focal length FW at the wide-angle end of the zoom lens satisfy the following condition:

[0118] 4.349≤|f4 / FW|≤4.684;

[0119] 3.643≤|f5 / FW|≤3.882;

[0120] 1.647≤|f6 / FW|≤1.709;

[0121] 4.016≤|f7 / FW|≤4.220.

[0122] In this embodiment, by limiting the focal length of each lens and the wide-angle end to satisfy the above relationship, the light can be reasonably shrunk to form an image on the image plane, thereby adapting to the 1 / 1.8″ target surface.

[0123] In a specific embodiment, optionally, the focal length FW at the wide-angle end of the zoom lens and the optical distortion DIS satisfy the following condition: 0.292<|DIS / FW|<1.881.

[0124] At this time, the zoom lens can have smaller distortion without affecting the imaging effect.

[0125] In a specific embodiment, optionally, the movable distance of the first zoom lens group 200 on the optical axis is between ZOL1 and the total optical system length TTL of the zoom lens, and the following condition is satisfied: 0.282≤ZOL1 / TTL≤0.337;

[0126] The movable distance ZOL2 of the second zoom lens group 300 on the optical axis and the total optical system length TTL of the zoom lens satisfy the following condition: 0.107≤ZOL2 / TTL≤0.125.

[0127] At this time, by limiting the total optical length of the two zoom lens groups and the zoom lens to meet the above range, the total length of the lens can be compressed and the volume of the zoom lens can be reduced, which is conducive to realizing a miniaturized zoom lens and expanding the applicable scenarios.

[0128] In a specific embodiment, optionally, the image plane size HI of the zoom lens and the total length TTL of the optical system satisfy the following condition: 0.070≤HI / TTLT≤0.082.

[0129] In this embodiment, by controlling the ratio of the lens image plane size and the total optical length to meet the above range, the volume of the lens can be controlled to the greatest extent, and the image plane size can be enlarged as much as possible while ensuring the volume, thereby achieving the purpose of small volume and large target surface.

[0130] In summary, the embodiment of the utility model uses 15 lenses and a certain thickness of flat glass, and realizes that the total optical length is ≤120mm, the zoom range is 6.8mm≤≤195mm under the 1 / 1.8″ target surface, and in the 436nm-656nm band, it has the advantages of large magnification, large aperture, small distortion, and high image quality. It is an all-glass five-element zoom lens suitable for use in most situations.

[0131] Based on the same concept above, the utility model provides three different specific embodiments, and the relationship between the optical power and the design range of related physical optical parameters are shown in Table 1:

[0132] Table 1 Relationship between the focal powers of the lenses and the design values ​​of the relevant physical optical parameters in the three embodiments

[0133]

[0134]

[0135] like Figure 1 and Figure 2 The parameter design values ​​of each lens in the zoom lens of the first embodiment are shown in Table 2:

[0136] Table 2 Design values ​​of each lens in the zoom lens in Example 1

[0137]

[0138]

[0139] The surface numbers in Table 2 are numbered according to the order of the surfaces of each lens; among them, "STO" represents the aperture of the zoom lens; the radius of curvature represents the curvature of the lens surface, a positive value represents that the surface is bent toward the image side, and a negative value represents that the surface is bent toward the object side; "INF" indicates that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, the refractive index represents the ability of the material between the current surface and the next surface to deflect light, and the space represents that the current position is air with a refractive index of 1. The Abbe number represents the dispersion characteristics of the material between the current surface and the next surface to light. The zoom interval values ​​in Table 2 above are shown in Table 3:

[0140] Table 3 A design value of the zoom interval of the zoom lens at the wide-angle end and the telephoto end in Example 1

[0141] Wide angle Telephoto end Zoom interval 1 -36.9166 -0.7549 Zoom interval 2 36.9166 0.7549 Zoom interval 3 12.2071 -2.0004 Zoom interval 4 -12.2071 2.0004 Zoom interval 5 -9.9560 -0.7748 Zoom interval 6 9.9560 0.7748

[0142] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0143]

[0144] Wherein, z is the axial vector height of the aspheric surface in the Z direction; r is the height of the aspheric surface; c is the curvature of the fitted spherical surface, which is the inverse of the radius of curvature; k is the fitted cone coefficient; AG is the coefficient of the 4th, 6th, 8th, 10th, 12th, 14th, and 16th order terms of the aspheric polynomial. The even-order coefficients of each aspheric surface in the above embodiment 1 are shown in Table 4:

[0145] Table 4 Aspheric parameters of each lens in the zoom lens of Example 1

[0146]

[0147]

[0148] Surface number D E F G S12 5.749238E-09 -4.105097E-11 1.057423E-13 0.000000E+00 S13 2.065579E-09 -5.176954E-12 -5.844167E-14 0.000000E+00 S23 -4.372086E-09 8.895715E-11 -1.043891E-12 0.000000E+00 S24 -3.669801E-09 6.771719E-11 -9.996667E-13 0.000000E+00 S33 3.657542E-08 -7.469422E-10 -5.615990E-11 0.000000E+00 S34 1.597196E-07 -6.926296E-09 6.345857E-11 0.000000E+00

[0149] Among them, -5.948091E-04 means that the coefficient A of the surface number S12 is -5.948091*10 -4 , and so on.

[0150] The parameter indexes of the zoom lens in the first embodiment are shown in Table 5:

[0151] Table 5 Parameters of the zoom lens in Example 1

[0152]

[0153] Figure 3 yes Figure 1 and Figure 2 The field curvature distortion diagram of the zoom lens at the wide-angle end is shown in the figure. In the left coordinate system of the figure, the horizontal coordinate represents the magnitude of the field curvature, and the unit is mm; the vertical coordinate represents the normalized image height, and there is no unit; T represents the meridian, and S represents the arc loss; the zoom lens provided in the first embodiment is effectively controlled in terms of field curvature, that is, when imaging, the difference between the image quality at the center and the image quality at the periphery is small; in the right coordinate system, the horizontal coordinate represents the magnitude of the distortion, and the unit is %; the vertical coordinate represents the normalized image height, and there is no unit. Figure 3 It can be seen that the distortion of the zoom lens provided in the first embodiment is well corrected, and the imaging distortion is small.

[0154] Figure 4 yes Figure 1 and Figure 2The light fan diagram of the zoom lens at the wide-angle end is shown in the figure. The light fan diagram is one of the most commonly used evaluation methods in modern optical design. The horizontal axis is the beam diameter, and the vertical axis is the vertical axis aberration. The most ideal curve is a straight line that coincides with the horizontal axis, indicating that all light rays converge at the same point on the image plane, and the corresponding interval on the vertical axis of the curve is the maximum dispersion range of the light beam on the ideal image plane. The light fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also indicate the size of the vertical axis chromatic aberration. Figure 4 It can be seen that the zoom lens is close to the horizontal axis at each wavelength in each field of view, indicating that the vertical axis aberration of each wavelength of the system is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the system is also well corrected, thereby ensuring that the optical system can achieve high-resolution imaging requirements.

[0155] Figure 5 yes Figure 1 and Figure 2 The vertical axis chromatic aberration diagram of the zoom lens at the wide-angle end is shown. In the vertical axis chromatic aberration curve, the vertical direction represents the normalization of the field of view, and 0 represents the optical axis; the main wavelength uses 546nm, and the horizontal direction represents the offset relative to the main wavelength, in micrometers (um). Figure 5 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a good range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled and can meet the needs of wide spectrum applications.

[0156] Figure 6 yes Figure 1 and Figure 2 The axial aberration diagram of the zoom lens at the wide-angle end is shown. In this axial aberration curve, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis direction represents the maximum pupil radius; the main wavelength uses 546nm, and the horizontal direction represents the offset relative to the main wavelength, in millimeters (mm). Figure 6 It can be seen that the axial aberrations of normalized apertures of different wavelengths from 0.2 to 0.9 are all controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the telephoto end is well controlled.

[0157] Figure 7 yes Figure 1 and Figure 2 The field curvature distortion diagram of the zoom lens at the telephoto end is shown in Figure 7 It can be seen that the distortion of the zoom lens provided in the first embodiment is well corrected, and the imaging distortion is small.

[0158] Figure 8 yes Figure 1 and Figure 2 The light fan diagram of the zoom lens at the telephoto end is shown in Figure 8It can be seen that the zoom lens is close to the horizontal axis at each wavelength in each field of view, indicating that the vertical axis aberration of each wavelength of the system is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the system is also well corrected, thereby ensuring that the optical system can achieve high-resolution imaging requirements.

[0159] Fig. 9 yes Figure 1 and Figure 2 The vertical axis chromatic aberration diagram of the zoom lens at the telephoto end is shown in Fig. 9 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a good range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled and can meet the needs of wide spectrum applications.

[0160] Fig.10 yes Figure 1 and Figure 2 The axial aberration diagram of the zoom lens at the telephoto end is shown in Fig.10 It can be seen that the axial aberrations of normalized apertures of different wavelengths from 0 to 0.7 are all controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the telephoto end is well controlled.

[0161] Fig.11 1 is a schematic structural diagram of a zoom lens at the wide-angle end provided by Embodiment 2 of the present utility model. Fig.12 yes Fig.11 The structure diagram of the zoom lens at the telephoto end is shown in FIG. Fig.11 and Fig.12 , the parameter design values ​​of each lens in the zoom lens of the second embodiment are shown in Table 6:

[0162] Table 6 Design values ​​of each lens in the zoom lens in Example 2

[0163]

[0164]

[0165] The surface numbers in Table 6 are numbered according to the order of the surfaces of each lens; among them, "STO" represents the aperture of the zoom lens; the radius of curvature represents the curvature of the lens surface, a positive value represents that the surface is bent toward the image side, and a negative value represents that the surface is bent toward the object side; "INF" indicates that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, the refractive index represents the ability of the material between the current surface and the next surface to deflect light, and the space represents that the current position is air with a refractive index of 1. The Abbe number represents the dispersion characteristics of the material between the current surface and the next surface to light. The zoom interval values ​​in Table 6 above are shown in Table 7:

[0166] Table 7 A design value of the zoom interval of the zoom lens at the wide-angle end and the telephoto end in Example 2

[0167] Wide angle Telephoto end Zoom interval 1 -37.1507 -0.7550 Zoom interval 2 37.1507 0.7550 Zoom interval 3 12.8013 -1.9178 Zoom interval 4 -12.8013 1.9178 Zoom interval 5 -9.9319 -0.8060 Zoom interval 6 9.9319 0.8060

[0168] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0169]

[0170] Wherein, z is the axial vector height of the aspheric surface in the Z direction; r is the height of the aspheric surface; c is the curvature of the fitted spherical surface, which is the inverse of the radius of curvature; k is the fitted cone coefficient; AG is the coefficient of the 4th, 6th, 8th, 10th, 12th, 14th, and 16th order terms of the aspheric polynomial. The even-order coefficients of each aspheric surface in the above-mentioned embodiment 2 are shown in Table 8:

[0171] Table 8 Aspheric parameters of each lens in the zoom lens of Example 2

[0172]

[0173]

[0174] Surface number D E F G S12 5.751607E-09 -4.042231E-11 1.128990E-13 -9.347831E-17 S13 2.063613E-09 -5.076990E-12 -5.426705E-14 6.068549E-17 S23 -4.355750E-09 8.951644E-11 -1.039013E-12 -2.251016E-16 S24 -3.678677E-09 6.722921E-11 -1.007678E-12 1.674090E-16 S33 3.552274E-08 -7.200637E-10 -5.365842E-11 2.439534E-13 S34 1.636846E-07 -6.825614E-09 6.615276E-11 -9.728289E-14

[0175] Among them, -5.977353E-04 means that the coefficient A of the surface number S12 is -5.977353*10 -4 , and so on.

[0176] The parameter indicators of the zoom lens in the second embodiment are shown in Table 9:

[0177] Table 9 Parameters of the zoom lens in Example 2

[0178]

[0179] Fig.13 yes Fig.11 and Fig.12 The field curvature distortion diagram of the zoom lens at the wide-angle end is shown in Fig.13 It can be seen that the distortion of the zoom lens provided in the second embodiment is well corrected, and the imaging distortion is small.

[0180] Fig.14 yes Fig.11 and Fig.12 The light fan diagram of the zoom lens at the wide-angle end is shown in Fig.14It can be seen that the zoom lens is close to the horizontal axis at each wavelength in each field of view, indicating that the vertical axis aberration of each wavelength of the system is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the system is also well corrected, thereby ensuring that the optical system can achieve high-resolution imaging requirements.

[0181] Fig.15 yes Fig.11 and Fig.12 The vertical axis chromatic aberration diagram of the zoom lens at the wide-angle end is shown in Fig.15 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a good range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled and can meet the needs of wide spectrum applications.

[0182] Fig.16 yes Fig.11 and Fig.12 The axial aberration diagram of the zoom lens at the wide-angle end is shown in Fig.16 It can be seen that the axial aberrations of normalized apertures of different wavelengths from 0.3 to 1.0 are all controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the telephoto end is well controlled.

[0183] Fig.17 yes Fig.11 and Fig.12 The field curvature distortion diagram of the zoom lens at the telephoto end is shown in Fig.17 It can be seen that the distortion of the zoom lens provided in the second embodiment is well corrected, and the imaging distortion is small.

[0184] Fig.18 yes Fig.11 and Fig.12 The light fan diagram of the zoom lens at the telephoto end is shown in Fig.18 It can be seen that the zoom lens is close to the horizontal axis at each wavelength in each field of view, indicating that the vertical axis aberration of each wavelength of the system is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the system is also well corrected, thereby ensuring that the optical system can achieve high-resolution imaging requirements.

[0185] Fig.19 yes Fig.11 and Fig.12 The vertical axis chromatic aberration diagram of the zoom lens at the telephoto end is shown in Fig.19 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a good range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled and can meet the needs of wide spectrum applications.

[0186] Fig. 20 yes Fig.11 and Fig.12 The axial aberration diagram of the zoom lens at the telephoto end is shown in Fig. 20It can be seen that the axial aberrations of normalized apertures of different wavelengths from 0.3 to 0.7 are all controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the telephoto end is well controlled.

[0187] Fig.21 1 is a schematic diagram of the structure of a zoom lens at the wide-angle end provided by Embodiment 3 of the present utility model. Fig. 22 yes Fig.21 The structure diagram of the zoom lens at the telephoto end is shown in FIG. Fig.21 and Fig. 22 , the parameter design values ​​of each lens in the zoom lens of the third embodiment are shown in Table 10:

[0188] Table 10: Design values ​​of each lens in the zoom lens in Example 3

[0189]

[0190]

[0191] The surface numbers in Table 10 are numbered according to the order of the surfaces of each lens; among them, "STO" represents the aperture of the zoom lens; the radius of curvature represents the curvature of the lens surface, a positive value represents that the surface is bent toward the image side, and a negative value represents that the surface is bent toward the object side; "INF" indicates that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, the refractive index represents the ability of the material between the current surface and the next surface to deflect light, and the space represents that the current position is air with a refractive index of 1. The Abbe number represents the dispersion characteristics of the material between the current surface and the next surface to light. The zoom interval values ​​in Table 10 above are shown in Table 11:

[0192] Table 11 A design value of the zoom interval of the zoom lens at the wide-angle end and the telephoto end in Example 3

[0193]

[0194]

[0195] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0196]

[0197] Wherein, z is the axial vector height of the aspheric surface in the Z direction; r is the height of the aspheric surface; c is the curvature of the fitted spherical surface, which is the inverse of the radius of curvature; k is the fitted cone coefficient; AG is the coefficient of the 4th, 6th, 8th, 10th, 12th, 14th, and 16th order terms of the aspheric polynomial. The even-order coefficients of each aspheric surface in the above-mentioned embodiment 3 are shown in Table 12:

[0198] Table 12 Aspheric parameters of each lens in the zoom lens of Example 3

[0199] Surface number Cone coefficient A B C S12 -26.1642 -6.042621E-04 1.791120E-05 -4.076528E-07 S13 12.8708 -3.362430E-04 8.590754E-06 -1.986797E-07 S23 0.1292 -4.376365E-05 -2.637103E-06 8.460887E-08 S24 6.9640 9.944372E-05 -1.704265E-06 6.958171E-08 S33 4.6987 6.253119E-04 -1.663916E-04 4.112855E-06 S34 441.2438 1.143345E-03 -1.770753E-04 3.175366E-06

[0200]

[0201]

[0202] Among them, -6.042621E-04 means that the coefficient A of the surface number S12 is -6.042621*10 -4 , and so on.

[0203] The parameter indicators of the zoom lens in the third embodiment are shown in Table 13:

[0204] Table 13 Parameters of the zoom lens in Example 3

[0205]

[0206] Fig.23 yes Fig.21 and Fig. 22 The field curvature distortion diagram of the zoom lens at the wide-angle end is shown in Fig.23 It can be seen that the distortion of the zoom lens provided in the third embodiment is well corrected, and the imaging distortion is small.

[0207] Fig.24 yes Fig.21 and Fig. 22 The light fan diagram of the zoom lens at the wide-angle end is shown in Fig.24 It can be seen that the zoom lens is close to the horizontal axis at each wavelength in each field of view, indicating that the vertical axis aberration of each wavelength of the system is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the system is also well corrected, thereby ensuring that the optical system can achieve high-resolution imaging requirements.

[0208] Fig.25 yes Fig.21 and Fig. 22 The vertical axis chromatic aberration diagram of the zoom lens at the wide-angle end is shown in Fig.25 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a good range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled and can meet the needs of wide spectrum applications.

[0209] Fig.26 yes Fig.21 and Fig. 22 The axial aberration diagram of the zoom lens at the wide-angle end is shown in Fig.26It can be seen that the axial aberrations of normalized apertures of different wavelengths from 0 to 1.0 are all controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the telephoto end is well controlled.

[0210] Fig. 27 yes Fig.21 and Fig. 22 The field curvature distortion diagram of the zoom lens at the telephoto end is shown in Fig. 27 It can be seen that the distortion of the zoom lens provided in the second embodiment is well corrected, and the imaging distortion is small.

[0211] Fig.28 yes Fig.11 and Fig.12 The light fan diagram of the zoom lens at the telephoto end is shown in Fig.28 It can be seen that the zoom lens is close to the horizontal axis at each wavelength in each field of view, indicating that the vertical axis aberration of each wavelength of the system is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the system is also well corrected, thereby ensuring that the optical system can achieve high-resolution imaging requirements.

[0212] Fig.29 yes Fig.21 and Fig. 22 The vertical axis chromatic aberration diagram of the zoom lens at the telephoto end is shown in Fig.29 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a good range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled and can meet the needs of wide spectrum applications.

[0213] Fig.30 yes Fig.21 and Fig. 22 The axial aberration diagram of the zoom lens at the telephoto end is shown in Fig.30 It can be seen that the axial aberrations of normalized apertures of different wavelengths from 0 to 1.0 are all controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the telephoto end is well controlled.

[0214] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention is described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A zoom lens, characterized in that: The lens comprises a first fixed lens group with positive focal power, a first zoom lens group with negative focal power, an aperture, a second zoom lens group with positive focal power, a focus lens group with positive focal power, and a second fixed lens group with negative focal power, which are arranged in sequence from the object side to the image side along the optical axis; The first fixed lens group includes a first lens with negative optical power, a second lens with positive optical power, a third lens with positive optical power, and a fourth lens with positive optical power; The first zoom lens group includes a fifth lens with negative optical power, a sixth lens with negative optical power, and a seventh lens with positive optical power; The second zoom lens group includes an eighth lens with positive optical power, a ninth lens with positive optical power, a tenth lens with negative optical power, and an eleventh lens with positive optical power; The focusing lens group includes a twelfth lens having a positive optical power and a thirteenth lens having a negative optical power; The second fixed lens group includes a fourteenth lens having a positive optical power and a fifteenth lens having a negative optical power; During the zooming process, the positions of the first fixed lens group and the second fixed lens group are fixed, the first zoom lens group and the second zoom lens group move along the optical axis to zoom, and the focus lens group moves along the optical axis to focus.

2. The zoom lens according to claim 1, wherein: The following conditions are satisfied between the focal length G1 of the first fixed lens group, the focal length G2 of the first variator group, the focal length G3 of the second variator group, the focal length G4 of the focus lens group, the focal length G5 of the second fixed lens group and the focal length FW of the zoom lens at the wide angle end: 7.924≤|G1 / FW|≤8.377; 1.503≤|G2 / FW|≤1.657; 4.327≤|G3 / FW|≤9.343; 3.916≤|G4 / FW|≤4.333; 9.151≤|G5 / FW|≤71.

320.

3. The zoom lens according to claim 1, wherein: The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the twelfth lens, the thirteenth lens and the fourteenth lens are all glass spherical lenses; The sixth lens, the eleventh lens and the fifteenth lens are glass aspherical lenses.

4. The zoom lens according to claim 3, wherein: The refractive index Nd1 and the Abbe number Vd1 of the sixth lens, the refractive index Nd2 and the Abbe number Vd2 of the eleventh lens, and the refractive index Nd3 and the Abbe number Vd3 of the fifteenth lens satisfy the following conditions: 1.45≤Nd1≤1.55;50.00≤Vd1≤95.00; 1.45≤Nd2≤1.55;74.00≤Vd2≤95.00; 1.45≤Nd3≤1.80;63.00≤Vd3≤95.

00.

5. The zoom lens according to claim 1, wherein: The object side surface of the first lens is convex, the object side and image side surfaces of the second lens are convex-convex, the object side and image side surfaces of the third lens are convex-convex, and the object side and image side surfaces of the fourth lens are convex-concave; The object side and image side surfaces of the fifth lens are convex-concave, the object side and image side surfaces of the sixth lens are concave-concave, and the object side and image side surfaces of the seventh lens are convex-convex; The object side and image side surfaces of the eighth lens are convex-convex, the object side surface of the ninth lens is convex, the object side and image side surfaces of the tenth lens are concave-concave, and the object side and image side surfaces of the eleventh lens are convex-concave; The object side surface of the twelfth lens is convex, and the object side and image side surfaces of the thirteenth lens are concave-convex; The object side and image side surfaces of the fourteenth lens are concave-convex, and the object side and image side surfaces of the fifteenth lens are concave-convex.

6. The zoom lens according to claim 1, wherein: The first lens and the second lens are cemented together to form a first cemented lens group; The ninth lens and the tenth lens are cemented together to form a second cemented lens group; The twelfth lens and the thirteenth lens are cemented together to form a third cemented lens group.

7. The zoom lens according to claim 6, wherein: The focal length f8 of the first cemented lens group and the focal length FW at the wide-angle end of the zoom lens satisfy the following condition: 56.464≤f8 / FW≤60.

887.

8. The zoom lens according to claim 1, wherein: The focal length f1 of the fifth lens, the focal length f2 of the sixth lens, the focal length f3 of the seventh lens and the focal length FW of the zoom lens at the wide angle end satisfy the following condition: 1.817≤|f1 / FW|≤2.002; 3.450≤|f2 / FW|≤3.942; 4.905≤|f3 / FW|≤5.645; The focal length f4 of the eighth lens, the focal length f5 of the ninth lens, the focal length f6 of the tenth lens, the focal length f7 of the eleventh lens and the focal length FW at the wide-angle end of the zoom lens satisfy the following condition: 4.349≤|f4 / FW|≤4.684; 3.643≤|f5 / FW|≤3.882; 1.647≤|f6 / FW|≤1.709; 4.016≤|f7 / FW|≤4.

220.

9. The zoom lens according to claim 1, wherein: The focal length FW at the wide-angle end of the zoom lens and the optical distortion DIS satisfy the following condition: 0.292<|DIS / FW|<1.

881.

10. The zoom lens according to claim 1, wherein: The movable distance of the first zoom lens group on the optical axis is ZOL1 and the total length TTL of the optical system of the zoom lens satisfies the following condition: 0.282≤ZOL1 / TTL≤0.337; The movable distance of the second zoom lens group on the optical axis is ZOL2 and the total length of the optical system of the zoom lens is TTL, which satisfies the following condition: 0.107≤ZOL2 / TTL≤0.

125.

11. The zoom lens according to claim 1, wherein: The image plane size HI of the zoom lens and the total length TTL of the optical system satisfy the following condition: 0.070≤HI / TTLT≤0.082.

Images