Zoom lens and imaging device

Abstract

The invention relates to the field of optics, in particular to a zoom lens and an imaging device.The zoom lens is sequentially composed of a first fixed lens group with positive focal power, a zoom lens group with negative focal power, a second fixed lens group with positive focal power, a focusing lens group with positive focal power and a third fixed lens group with negative focal power from the object plane side to the image plane side; the zoom lens group and the focusing lens group move in the main optical axis direction of the zoom lens; the zoom lens satisfies the following conditional expressions: 2 < ft / fw < 3; fno is less than 1.8; tTL is less than 150 mm; wherein ft is the focal length of the zoom lens in a telescopic state, fw is the focal length of the zoom lens in a wide-angle state, fno is the number of apertures of the zoom lens, and TTL is the total optical length of the zoom lens. Through the limitation of the structure and parameters, the size of the zoom lens is increased to a certain extent, the aperture in the zoom lens is increased, and the brightness of the zoom lens is improved.

Description

Technical Field

[0001] The present invention relates to the field of optics, and in particular to a zoom lens and an imaging device. Background Art

[0002] A zoom lens is a lens that can change its focal length within a certain range, thereby obtaining different widths of field of view, different sizes of images and different ranges of scenery. A zoom lens can change the shooting range by changing the focal length without changing the shooting distance, so it is very helpful for picture composition.

[0003] Currently, existing small-magnification zoom lenses are usually smaller in size and have fewer lenses within the zoom lens. Therefore, the aperture within the zoom lens is also smaller, and the brightness of the zoom lens is lower. Summary of the Invention

[0004] The present invention solves existing technical problems and provides a zoom lens and an imaging device. Through the above-mentioned structure and parameter limitations, the volume of the zoom lens is increased to a certain extent, the aperture in the zoom lens is increased, and the brightness of the zoom lens is increased.

[0005] The technical solutions provided by the present invention are as follows:

[0006] A zoom lens, comprising, from the object side to the image side, a first fixed lens group with positive optical power, a variable magnification lens group with negative optical power, a second fixed lens group with positive optical power, a focusing lens group with positive optical power, and a third fixed lens group with negative optical power;

[0007] The zoom lens group and the focusing lens group move in the direction of the main optical axis of the zoom lens;

[0008] The focusing lens group is composed of a first focusing lens with negative optical power and a second focusing lens with positive optical power from the object plane side to the image plane side, and the first focusing lens and the second focusing lens are glued together;

[0009] The zoom lens satisfies the following conditional formula:

[0010] 2<ft / fw<3;

[0011] Fno<1.8;

[0012] TTL<150mm;

[0013] Wherein, ft is the focal length of the zoom lens in the telephoto state, fw is the focal length of the zoom lens in the wide-angle state, fno is the aperture number of the zoom lens, and TTL is the total optical length of the zoom lens.

[0014] By limiting the above structure and parameters, the volume of the zoom lens is increased to a certain extent, the aperture in the zoom lens is increased, and the brightness of the zoom lens is increased.

[0015] Preferably, the first fixed lens group, the variable magnification lens group, the second fixed lens group, the focusing lens group, and the third fixed lens group each include a group of cemented lenses.

[0016] In this technical solution, by disposing the cemented lens, the chromatic aberration and spherical aberration in each lens group are reduced, thereby reducing the chromatic aberration and spherical aberration of the zoom lens and increasing the resolution of the zoom lens.

[0017] Preferably, the first lens group consists of a first fixed lens with negative optical power, a second fixed lens with positive optical power and a third fixed lens with positive optical power from the object side to the image side, and the first fixed lens and the second fixed lens are cemented together.

[0018] Preferably, the zoom lens group consists of, from the object side to the image side, a first zoom lens with negative optical focal length, a second zoom lens with negative optical focal length, a third zoom lens with positive optical focal length, a fourth zoom lens with negative optical focal length, and the second zoom lens and the third zoom lens cemented together.

[0019] Preferably, the second lens group is composed of a fourth fixed lens with positive focal power, a fifth fixed lens with negative focal power, a sixth fixed lens with positive focal power and a seventh fixed lens with negative focal power from the object plane side to the image plane side, and the fifth fixed lens, the sixth fixed lens and the seventh fixed lens form a triplet lens.

[0020] Preferably, the third fixed lens group is composed of an eighth fixed lens with positive focal power, a ninth fixed lens with positive focal power, a tenth fixed lens with negative focal power and an eleventh fixed lens with positive focal power from the object plane side to the image plane side, and the ninth fixed lens and the tenth fixed lens are cemented together.

[0021] Preferably, the zoom lens satisfies the following conditional formula:

[0022] 0.8<XG2 / fw<1.5;

[0023] Wherein, XG2 is the maximum moving distance of the zoom lens group.

[0024] In this technical solution, by limiting the maximum moving distance of the zoom lens group, the maximum moving distance of the zoom lens group is reduced on the basis of achieving zooming of the zoom lens, thereby achieving miniaturization of the zoom lens.

[0025] Preferably, the zoom lens satisfies the following conditional formula:

[0026] XG4 / XG2<0.5;

[0027] Wherein, XG4 is the maximum moving distance of the focusing lens group.

[0028] In this technical solution, by limiting the moving distance of the focusing lens group, the zoom lens is miniaturized, and at the same time, the resolution of the zoom lens can be increased to a certain extent.

[0029] Preferably, the focusing lens group and the zoom lens group each include at least one aspherical lens.

[0030] In this technical solution, by disposing the aspheric lens in the movable lens group, the phase difference between the focusing lens group and the variable magnification lens group in the zoom lens is reduced at a certain time, thereby improving the imaging quality of the zoom lens.

[0031] Preferably, the zoom lens satisfies the following conditional formula:

[0032] fG3 / fw>3;

[0033] Wherein, fG3 is the focal length of the second fixed lens group.

[0034] In this technical solution, by limiting the focal length of the second fixed lens group, the possibility of the focal length of the focusing lens group and the zoom lens group being too large or too small is reduced. At the same time, the moving distance of the focusing lens group and the zoom lens group can be reduced, thereby achieving miniaturization of the zoom lens.

[0035] Preferably, the zoom lens satisfies the following conditional formula:

[0036] -0.25<fG4 / fG2<-0.15;

[0037] Wherein, fG2 is the focal length of the zoom lens group, and fG4 is the focal length of the focusing lens group.

[0038] In this technical solution, by limiting the distance between the zoom lens group and the focusing lens group, the moving distance of the focusing lens group is reduced, the imaging quality of the zoom lens is improved, and the miniaturization of the zoom lens is achieved.

[0039] In this technical solution, by limiting the moving direction, the efficiency of the first lens group and the second lens group in changing the magnification when moving is further reduced, thereby achieving miniaturization of the zoom lens.

[0040] Another object of the present invention is to provide an imaging device comprising: a zoom lens; and an imaging element configured to receive an image formed by the zoom lens.

[0041] Compared with the prior art, the zoom lens and imaging device provided by the present invention have the following beneficial effects:

[0042] 1. Through the above-mentioned structure and parameter limitations, the volume of the zoom lens is increased to a certain extent, the aperture in the zoom lens is increased, and the brightness of the zoom lens is increased.

[0043] 2. By limiting the maximum moving distance of the zoom lens group, the maximum moving distance of the zoom lens group is reduced while achieving zooming of the zoom lens, thereby realizing miniaturization of the zoom lens.

[0044] 3. By limiting the focal length of the second fixed lens group, the possibility of the focal length of the focusing lens group and the zoom lens group being too large or too small is reduced. At the same time, the moving distance of the focusing lens group and the zoom lens group can be reduced, thereby achieving miniaturization of the zoom lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The preferred embodiments will be described below in a clear and understandable manner with reference to the accompanying drawings to further illustrate the above-mentioned characteristics, technical features, advantages and implementation methods of a zoom lens and an imaging device.

[0046] Figure 1 It is a structural schematic diagram of a zoom lens of the present invention;

[0047] Figure 2 This is an aberration diagram of a zoom lens in a wide-angle state according to the present invention;

[0048] Figure 3 This is a coma diagram of a zoom lens in a wide-angle state according to the present invention;

[0049] Figure 4 This is an aberration diagram of a zoom lens in a telephoto state according to the present invention;

[0050] Figure 5 This is a coma diagram of a zoom lens in a telephoto state according to the present invention;

[0051] Figure 6 is a schematic structural diagram of another zoom lens of the present invention;

[0052] Figure 7 is an aberration diagram of another zoom lens in wide-angle state according to the present invention;

[0053] Figure 8 is a coma diagram of another zoom lens in wide-angle state according to the present invention;

[0054] Figure 9 is an aberration diagram of another zoom lens in the telephoto state of the present invention;

[0055] Figure 10 This is a coma diagram of another zoom lens in the telephoto state of the present invention.

[0056] Explanation of the accompanying drawings: G1, first fixed lens group; G2, zoom lens group; G3, second fixed lens group; G4, focusing lens group; G5, third fixed lens group; G6, auxiliary component; a1, first fixed lens; a2, second fixed lens; a3, third fixed lens; a4, fourth fixed lens; a5, fifth fixed lens; a6, sixth fixed lens; a7, seventh fixed lens; a8, eighth fixed lens; a9, ninth fixed lens; a10, tenth fixed lens; a11, eleventh fixed lens; b1, first zoom lens; b2, second zoom lens; b3, third zoom lens; c1, first focusing lens; c2, second focusing lens; STO, aperture; CG1, first protective glass; CG2, second protective glass. DETAILED DESCRIPTION

[0057] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0058] To simplify the drawings, only portions relevant to the invention are schematically depicted in each figure; they do not represent the actual structure of the product. Furthermore, to simplify the drawings and facilitate understanding, in some figures, only one component with the same structure or function is schematically depicted or labeled. In this document, "one" not only means "only one" but also "more than one."

[0059] Example 1

[0060] like Figure 1 and Figure 6 As shown, a zoom lens is composed of, from the object side to the image side, a first fixed lens group G1 with positive optical power, a variator lens group G2 with negative optical power, a second fixed lens group G3 with positive optical power, a focusing lens group G4 with positive optical power, and a third fixed lens group G5 with negative optical power;

[0061] The zoom lens group G2 and the focusing lens group G4 move in the direction of the main optical axis of the zoom lens;

[0062] The focusing lens group G4 is composed of a first focusing lens c1 with negative optical power and a first focusing lens c2 with positive optical power from the object plane side to the image plane side, wherein the first focusing lens c1 and the first focusing lens c2 are cemented together;

[0063] The zoom lens satisfies the following conditional formula:

[0064] 2<ft / fw<3

[0065] Fno<1.8;

[0066] TTL<150mm;

[0067] Wherein, ft is the focal length of the zoom lens in the telephoto state, fw is the focal length of the zoom lens in the wide-angle state, fno is the aperture number of the zoom lens, and TTL is the total optical length of the zoom lens.

[0068] By limiting the above structure and parameters, the volume of the zoom lens is increased to a certain extent, the aperture in the zoom lens is increased, and the brightness of the zoom lens is increased.

[0069] The first fixed lens group G1, the variable magnification lens group G2, the second fixed lens group G3, the focusing lens group G4, and the third fixed lens group G5 each include a set of cemented lenses.

[0070] By setting up the cemented lens, the chromatic aberration and spherical aberration within each lens group are reduced, thereby reducing the chromatic aberration and spherical aberration of the zoom lens and increasing the resolution of the zoom lens.

[0071] The first lens group consists of a first fixed lens a1 with negative optical power, a second fixed lens a2 with positive optical power and a third fixed lens a3 with positive optical power from the object side to the image side. The first fixed lens a1 and the second fixed lens a2 are cemented together.

[0072] The variator lens group G2 is composed of a first variator lens b1 with negative optical power, a second variator lens b2 with negative optical power, a third variator lens b3 with positive optical power, a fourth variator lens with negative optical power, and a cemented combination of the second variator lens b2 and the third variator lens b3 from the object side to the image side.

[0073] The second lens group is composed of, from the object side to the image side, a fourth fixed lens a4 with positive optical focal length, a fifth fixed lens a5 with negative optical focal length, a sixth fixed lens a6 with positive optical focal length and a seventh fixed lens a7 with negative optical focal length. The fifth fixed lens a5, the sixth fixed lens a6 and the seventh fixed lens a7 form a triplet lens.

[0074] The third fixed lens group G5 is composed of, from the object side to the image side, an eighth fixed lens a8 with positive optical focal length, a ninth fixed lens a9 with positive optical focal length, a tenth fixed lens a10 with negative optical focal length, and an eleventh fixed lens a11 with positive optical focal length. The ninth fixed lens a9 and the tenth fixed lens a10 are cemented together.

[0075] The zoom lens satisfies the following conditional formula:

[0076] 0.8<XG2 / fw<1.5;

[0077] Wherein, XG2 is the maximum moving distance of the zoom lens group G2.

[0078] By limiting the maximum moving distance of the zoom lens group G2, the maximum moving distance of the zoom lens group G2 is reduced while achieving zooming of the zoom lens, thereby achieving miniaturization of the zoom lens.

[0079] The zoom lens satisfies the following conditional formula:

[0080] XG4 / XG2<0.5;

[0081] Wherein, XG4 is the maximum moving distance of the focusing lens group G4.

[0082] By limiting the moving distance of the focusing lens group G4, the zoom lens can be miniaturized while also increasing the resolution of the zoom lens to a certain extent.

[0083] The focusing lens group G4 and the zoom lens group G2 each include at least one aspherical lens.

[0084] By disposing the aspheric lens in the movable lens group, the phase difference between the focusing lens group G4 and the variable magnification lens group G2 in the zoom lens is reduced at a certain time, thereby improving the imaging quality of the zoom lens.

[0085] The zoom lens satisfies the following conditional formula:

[0086] fG3 / fw>3;

[0087] Wherein, fG3 is the focal length of the second fixed lens group G3.

[0088] By limiting the focal length of the second fixed lens group G3, the possibility of the focal length of the focusing lens group G4 and the zoom lens group G2 being too large or too small is reduced. At the same time, the moving distance of the focusing lens group G4 and the zoom lens group G2 can be reduced, thereby achieving miniaturization of the zoom lens.

[0089] The zoom lens satisfies the following conditional formula:

[0090] -0.25<fG4 / fG2<-0.15;

[0091] Wherein, fG2 is the focal length of the zoom lens group G2, and fG4 is the focal length of the focusing lens group G4.

[0092] By limiting the distance between the zoom lens group G2 and the focusing lens group G4, the moving distance of the focusing lens group G4 is reduced, the imaging quality of the zoom lens is improved, and the miniaturization of the zoom lens is achieved.

[0093] Example 2

[0094] like Figures 1 to 5 As shown, a zoom lens is composed of, from the object side to the image side, a first fixed lens group G1 with positive optical power, a variator lens group G2 with negative optical power, a second fixed lens group G3 with positive optical power, a focusing lens group G4 with positive optical power, a third fixed lens group G5 with negative optical power, and an auxiliary component G6;

[0095] The zoom lens group G2 and the focusing lens group G4 move in the direction of the main optical axis of the zoom lens;

[0096] The first lens group consists of a first fixed lens a1 with negative optical power, a second fixed lens a2 with positive optical power and a third fixed lens a3 with positive optical power from the object side to the image side. The first fixed lens a1 and the second fixed lens a2 are cemented together.

[0097] The variator lens group G2 is composed of a first variator lens b1 with negative optical power, a second variator lens b2 with negative optical power, a third variator lens b3 with positive optical power, a fourth variator lens with negative optical power, and a cemented combination of the second variator lens b2 and the third variator lens b3 from the object side to the image side.

[0098] The second lens group is composed of, from the object side to the image side, a fourth fixed lens a4 with positive optical focal length, a fifth fixed lens a5 with negative optical focal length, a sixth fixed lens a6 with positive optical focal length and a seventh fixed lens a7 with negative optical focal length. The fifth fixed lens a5, the sixth fixed lens a6 and the seventh fixed lens a7 form a triplet lens.

[0099] The focusing lens group G4 is composed of a first focusing lens c1 with negative optical power and a first focusing lens c2 with positive optical power from the object plane side to the image plane side, wherein the first focusing lens c1 and the first focusing lens c2 are cemented together;

[0100] The third fixed lens group G5 is composed of, from the object side to the image side, an eighth fixed lens a8 with positive optical focal length, a ninth fixed lens a9 with positive optical focal length, a tenth fixed lens a10 with negative optical focal length, and an eleventh fixed lens a11 with positive optical focal length. The ninth fixed lens a9 and the tenth fixed lens a10 are cemented together.

[0101] The auxiliary assembly G6 consists of a first cover glass CG1 and a second cover glass CG2 in order from the object plane side to the image plane side.

[0102] Table 1 shows basic lens data of the zoom lens of this embodiment, Table 2 shows variable parameters in Table 1, and Table 3 shows aspherical coefficients.

[0103] The surface number column shows the surface number when the object side surface is set as the first surface and the numbers increase one by one toward the image side; the surface type column shows the surface type of a certain lens; the curvature radius column shows the curvature radius of a certain lens, when the curvature radius is positive, it indicates that the surface is curved toward the object side, and when the curvature radius is negative, it indicates that the surface is curved toward the image side; the center thickness column shows the surface spacing on the optical axis between each surface and the surface adjacent to its image side; the refractive index column shows the refractive index of a certain lens; and the Abbe number column shows the Abbe number of a certain lens.

[0104] In Table 2, the WIDE column indicates specific values of various variable parameters when the zoom lens is at the wide-angle end state, and the TELE column indicates specific values of various variable parameters when the zoom lens is at the telephoto end state.

[0105] In Table 3, K is the cone coefficient, and e is the scientific notation, for example, e-005 represents 10 -5 .

[0106]

Table 1

[0107]

[0108]

[0109]

Table 2

[0110] Wide TELE D1 0.56 17.7 D2 21.46 4.32 D3 6.84 2.21 D4 1 5.63

[0111]

Table 3

[0112]

[0113]

[0114] In this embodiment, fw=16mm, ft=40mm, fw / ft=2.5, fno=1.62-1.67, TTL=130mm;

[0115] Wherein, ft is the focal length of the zoom lens in the telephoto state, fw is the focal length of the zoom lens in the wide-angle state, fno is the aperture number of the zoom lens, and TTL is the total optical length of the zoom lens.

[0116] XG2=17.14mm, XG2 / fw=1.07;

[0117] XG4=4.63mm, XG4 / XG2=0.27;

[0118] Wherein, XG2 is the maximum moving distance of the zoom lens group G2, and XG4 is the maximum moving distance of the focusing lens group G4.

[0119] fG3=58.29mm, fG3 / fw=3.64;

[0120] fG3 is the focal length of the second fixed lens group G3.

[0121] fG4=-16.83mm, fG2=81.01mm, fG4 / fG2=-0.208;

[0122] Wherein, fG2 is the focal length of the zoom lens group G2, and fG4 is the focal length of the focusing lens group G4.

[0123] Example 3

[0124] like Figures 6 to 10 As shown, a zoom lens is composed of, from the object side to the image side, a first fixed lens group G1 with positive optical power, a variator lens group G2 with negative optical power, a second fixed lens group G3 with positive optical power, a focusing lens group G4 with positive optical power, a third fixed lens group G5 with negative optical power, and an auxiliary component G6;

[0125] The zoom lens group G2 and the focusing lens group G4 move in the direction of the main optical axis of the zoom lens;

[0126] The first lens group consists of a first fixed lens a1 with negative optical power, a second fixed lens a2 with positive optical power and a third fixed lens a3 with positive optical power from the object side to the image side. The first fixed lens a1 and the second fixed lens a2 are cemented together.

[0127] The variator lens group G2 is composed of a first variator lens b1 with negative optical power, a second variator lens b2 with negative optical power, a third variator lens b3 with positive optical power, a fourth variator lens with negative optical power, and a cemented combination of the second variator lens b2 and the third variator lens b3 from the object side to the image side.

[0128] The second lens group is composed of, from the object side to the image side, a fourth fixed lens a4 with positive optical focal length, a fifth fixed lens a5 with negative optical focal length, a sixth fixed lens a6 with positive optical focal length and a seventh fixed lens a7 with negative optical focal length. The fifth fixed lens a5, the sixth fixed lens a6 and the seventh fixed lens a7 form a triplet lens.

[0129] The focusing lens group G4 is composed of a first focusing lens c1 with negative optical power and a first focusing lens c2 with positive optical power from the object plane side to the image plane side, wherein the first focusing lens c1 and the first focusing lens c2 are cemented together;

[0130] The third fixed lens group G5 is composed of, from the object side to the image side, an eighth fixed lens a8 with positive optical focal length, a ninth fixed lens a9 with positive optical focal length, a tenth fixed lens a10 with negative optical focal length, and an eleventh fixed lens a11 with positive optical focal length. The ninth fixed lens a9 and the tenth fixed lens a10 are cemented together.

[0131] The auxiliary assembly G6 consists of a first cover glass CG1 and a second cover glass CG2 in order from the object plane side to the image plane side.

[0132] Basic lens data of the zoom lens of this embodiment are shown in Table 4, variable parameters in Table 4 are shown in Table 5, and aspheric coefficients are shown in Table 6.

[0133] The surface number column shows the surface number when the object side surface is set as the first surface and the numbers increase one by one toward the image side; the surface type column shows the surface type of a certain lens; the curvature radius column shows the curvature radius of a certain lens, when the curvature radius is positive, it indicates that the surface is curved toward the object side, and when the curvature radius is negative, it indicates that the surface is curved toward the image side; the center thickness column shows the surface spacing on the optical axis between each surface and the surface adjacent to its image side; the refractive index column shows the refractive index of a certain lens; and the Abbe number column shows the Abbe number of a certain lens.

[0134] In Table 5, the WIDE column indicates specific values of various variable parameters when the zoom lens is at the wide-angle end state, and the TELE column indicates specific values of various variable parameters when the zoom lens is at the telephoto end state.

[0135] In Table 6, K is the cone coefficient, and e is the scientific notation, for example, e-005 represents 10 -5 .

[0136]

Table 4

[0137]

[0138]

[0139]

Table 5

[0140] Wide TELE D1 0.5 20.21 D2 21.47 1.76 D3 9.95 1.5 D4 1 9.45

[0141]

Table 6

[0142]

[0143] In this embodiment, fw=16mm, ft=40mm, fw / ft=2.5, fno=1.57-1.65, TTL=130mm;

[0144] Wherein, ft is the focal length of the zoom lens in the telephoto state, fw is the focal length of the zoom lens in the wide-angle state, fno is the aperture number of the zoom lens, and TTL is the total optical length of the zoom lens.

[0145] XG2=19.71mm, XG2 / fw=1.23;

[0146] XG4=8.45mm, XG4 / XG2=0.429;

[0147] Wherein, XG2 is the maximum moving distance of the zoom lens group G2, and XG4 is the maximum moving distance of the focusing lens group G4.

[0148] fG3=122.58mm, fG3 / fw=7.66;

[0149] fG3 is the focal length of the second fixed lens group G3.

[0150] fG4=-16.61mm, fG2=99.93mm, fG4 / fG2=-0.166;

[0151] Wherein, fG2 is the focal length of the zoom lens group G2, and fG4 is the focal length of the focusing lens group G4.

[0152] Example 4

[0153] An imaging device, such as Figures 1 to 10 As shown, it includes: a zoom lens as described in any one of the above embodiments, and an imaging element, which is configured to receive an image formed by the zoom lens.

[0154] It should be noted that the above embodiments can be freely combined as needed. The above description is only a preferred embodiment of the present invention. It should be pointed out that those skilled in the art can make several improvements and modifications without departing from the principles of the present invention, and such improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A zoom lens, characterized in that: The zoom lens is composed of a first fixed lens group with positive optical power, a zoom lens group with negative optical power, a second fixed lens group with positive optical power, a focusing lens group with positive optical power, and a third fixed lens group with negative optical power, from the object side to the image side. The zoom lens group and the focusing lens group move in the direction of the main optical axis of the zoom lens; The focusing lens group is composed of a first focusing lens with negative optical power and a second focusing lens with positive optical power from the object plane side to the image plane side, and the first focusing lens and the second focusing lens are glued together; The zoom lens satisfies the following conditional formula: 2<ft / fw<3; Fno<1.8; TTL<150mm; Wherein, ft is the focal length of the zoom lens in the telephoto state, fw is the focal length of the zoom lens in the wide-angle state, fno is the aperture number of the zoom lens, and TTL is the total optical length of the zoom lens.

2. The zoom lens according to claim 1, wherein: The first fixed lens group, the variable magnification lens group, the second fixed lens group, the focusing lens group and the third fixed lens group each include a group of cemented lenses.

3. The zoom lens according to claim 1, wherein: The first lens group consists of a first fixed lens with negative optical power, a second fixed lens with positive optical power and a third fixed lens with positive optical power from the object side to the image side, and the first fixed lens and the second fixed lens are cemented together.

4. The zoom lens according to claim 1, wherein: The zoom lens group consists of a first zoom lens with negative optical power, a second zoom lens with negative optical power, a third zoom lens with positive optical power, a fourth zoom lens with negative optical power, and the second zoom lens and the third zoom lens are glued together from the object side to the image side.

5. The zoom lens according to claim 1, wherein: The second lens group is composed of a fourth fixed lens with positive optical power, a fifth fixed lens with negative optical power, a sixth fixed lens with positive optical power and a seventh fixed lens with negative optical power from the object side to the image side, and the fifth fixed lens, the sixth fixed lens and the seventh fixed lens form a triplet lens.

6. The zoom lens according to claim 1, wherein: The third fixed lens group is composed of an eighth fixed lens with positive focal power, a ninth fixed lens with positive focal power, a tenth fixed lens with negative focal power and an eleventh fixed lens with positive focal power from the object plane side to the image plane side, and the ninth fixed lens and the tenth fixed lens are cemented together.

7. The zoom lens according to claim 1, wherein: The zoom lens satisfies the following conditional formula: 0.8<XG2 / fw<1.5; Wherein, XG2 is the maximum moving distance of the zoom lens group.

8. The zoom lens according to claim 7, wherein: The zoom lens satisfies the following conditional formula: XG4 / XG2<0.5; Wherein, XG4 is the maximum moving distance of the focusing lens group.

9. The zoom lens according to claim 1, wherein: The focusing lens group and the variable magnification lens group each include at least one aspherical lens.

10. The zoom lens according to claim 1, wherein: The zoom lens satisfies the following conditional formula: fG3 / fw>3; Wherein, fG3 is the focal length of the second fixed lens group.

11. The zoom lens according to claim 1, wherein: The zoom lens satisfies the following conditional formula: -0.25<fG4 / fG2<-0.15; Wherein, fG2 is the focal length of the zoom lens group, and fG4 is the focal length of the focusing lens group.

12. An imaging device, characterized in that: include: The zoom lens according to any one of claims 1 to 11; and an imaging element configured to receive an image formed by the zoom lens.

Images