zoom lens

Abstract

The present invention provides a zoom lens. The zoom lens sequentially includes, from the object side to the image side, a first lens group, the first lens group including a first lens with a positive optical power; a second lens group with a negative optical power, the second lens group including a second lens with a negative optical power and a third lens with a negative optical power; a third lens group with a positive optical power, the third lens group including a fourth lens with a positive optical power, a fifth lens with a positive optical power, a sixth lens with a negative optical power, a seventh lens with a negative optical power, and an eighth lens with a positive optical power; satisfying: 1.9 < TTL / Δf < 2.6; satisfying: -1.6 < FG3 / FG2 < -1.2; satisfying: 1.6 < ft / f1 < 2.1. The present invention solves the problem that the existing zoom lens has difficulty in simultaneously achieving continuous zooming ability and high imaging quality.

Description

Technical Field

[0001] This invention relates to the field of optical imaging equipment technology, and more specifically, to a zoom lens. Background Technology

[0002] In recent years, with the continuous development of smartphones, users have increasingly higher demands for smartphone lenses, and at the same time, their performance requirements for lenses have also become higher, especially for zoom lenses. To meet the diverse shooting needs of users, smartphones often require multiple lenses with different designs to suit different shooting purposes. These lenses have different focal lengths to adapt to corresponding shooting needs. For high-end flagship models, four or more lenses are often required to cover various focal lengths. More lenses mean more CMOS image sensors, and more large-size, high-resolution sensors also mean higher production costs and more space occupied in the phone, which is very detrimental to reducing the weight and cost of the phone.

[0003] Given the current state of zoom lens development, to be applicable to mobile phones and cover a wide focal length range while meeting the characteristics of continuous zoom, it is necessary to rationally set up the various lens groups in the zoom lens, which is quite difficult to design. At the same time, it is also necessary to meet good image quality, which further increases the design difficulty.

[0004] In other words, existing zoom lenses suffer from the problem of simultaneously failing to achieve both continuous zoom capability and high image quality. Summary of the Invention

[0005] The main objective of this invention is to provide a zoom lens that solves the problem that existing zoom lenses cannot simultaneously achieve continuous zoom capability and high image quality.

[0006] To achieve the above object, according to one aspect of the present invention, there is provided a zoom lens, which sequentially includes from the object side to the image side: a first lens group, the first lens group includes a first lens with a positive optical power; a second lens group with a negative optical power, the second lens group includes a second lens with a negative optical power and a third lens with a negative optical power; a third lens group with a positive optical power, the third lens group includes a fourth lens with a positive optical power, a fifth lens with a positive optical power, a sixth lens with a negative optical power, a seventh lens with a negative optical power, and an eighth lens with a positive optical power; the second lens group and the third lens group are movably arranged on the optical axis, and by adjusting the positions of the second lens group and the third lens group on the optical axis, continuous zooming of the zoom lens is achieved; when the zoom lens is at the wide-angle end, the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length variable △f of the zoom lens when at the telephoto end and the wide-angle end satisfy: 1.9 < TTL / △f < 2.6; the effective focal length FG2 of the second lens group and the effective focal length FG3 of the third lens group satisfy: -1.6 < FG3 / FG2 < -1.2; the effective focal length ft of the zoom lens when at the telephoto end and the effective focal length f1 of the first lens satisfy: 1.6 < ft / f1 < 2.1.

[0007] Further, when the zoom lens is at the telephoto end, the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length ft of the zoom lens when at the telephoto end satisfy: 0.9 < TTL / ft < 1.3.

[0008] Further, the radius of curvature R4 of the image side surface of the second lens and the radius of curvature R5 of the object side surface of the third lens satisfy: -7.3 < (R4 + R5) / (R4 - R5) < -6.8.

[0009] Further, the radius of curvature R7 of the object side surface of the fourth lens, the radius of curvature R8 of the image side surface of the fourth lens and the effective focal length f4 of the fourth lens satisfy: 0.9 < (R7 + R8) / f4 < 1.4.

[0010] Further, the effective focal length FG3 of the third lens group, the effective focal length f4 of the fourth lens, the effective focal length f5 of the fifth lens and the effective focal length f8 of the eighth lens satisfy: 4.4 < (f4 + f5 + f8) / FG3 < 5.3.

[0011] Further, the radius of curvature R12 of the image side surface of the sixth lens and the radius of curvature R16 of the image side surface of the eighth lens satisfy: 0 < (R12 + R16) / R16 < 1.3.

[0012] Furthermore, when the zoom lens is at the wide-angle end, the air gap T12 between the first and second lenses on the optical axis, and the air gap T34 between the third and fourth lenses on the optical axis and the air gap T23 between the second and third lenses on the optical axis, satisfy the following condition: 4.5 < (T12 + T34) / T23 < 6.4.

[0013] Furthermore, the change in air gap ΔD1 between the first and second lenses of the zoom lens when switching from the wide-angle end to the telephoto end and the change in air gap ΔD2 between the third and fourth lenses of the zoom lens when switching from the wide-angle end to the telephoto end satisfy the following condition: 4.0 < |ΔD2 / ΔD1| < 5.2.

[0014] Furthermore, the air gap T67 between the sixth and seventh lenses on the optical axis, the air gap T56 between the fifth and sixth lenses on the optical axis, and the center thickness CT5 of the fifth lens satisfy the following relationship: 0.7 <T67 / (T56+CT5)<2.2。

[0015] Furthermore, when the zoom lens is at the telephoto end, the distance TDt between the object-side surface of the first lens and the image-side surface of the eighth lens on the optical axis satisfies the following relationship between the air gap T67 between the sixth and seventh lenses on the optical axis: 2.8 <TDt / T67<4.9。

[0016] Furthermore, the air gaps T67 between the sixth and seventh lenses on the optical axis, T78 between the seventh and eighth lenses on the optical axis, T45 between the fourth and fifth lenses on the optical axis, and T56 between the fifth and sixth lenses on the optical axis satisfy the following condition: 2.0 < (T67 + T78) / (T45 + T56) < 4.8.

[0017] Furthermore, the effective focal length f1 of the first lens and the effective focal length f8 of the eighth lens satisfy the following relationship: 0.9 <f1 / f8<1.4。

[0018] Furthermore, the change in effective focal length Δf when the zoom lens is at the telephoto end and the wide-angle end, and the change in air gap ΔD2 of the third and fourth lenses on the optical axis when the zoom lens switches from the wide-angle end to the telephoto end, satisfy the following condition: 2.2 < Δf / ΔD2 < 2.8.

[0019] Furthermore, the center thickness CT1 of the first lens and the edge thickness ET1 at the maximum effective radius of the first lens satisfy: 2.1 <CT1 / ET1<3.7。

[0020] Furthermore, the distance SAG32 on the optical axis between the intersection point of the image-side surface of the third lens and the effective half-aperture of the image-side surface of the third lens, and the distance SAG21 on the optical axis between the intersection point of the object-side surface of the second lens and the effective half-aperture of the object-side surface of the second lens, satisfy the following condition: -2.7 <SAG32 / SAG21<-2.0。

[0021] Furthermore, the effective focal length f1 of the first lens, the radius of curvature R1 of the object-side surface of the first lens, and the radius of curvature R2 of the image-side surface of the first lens satisfy the following relationship: -1.5 <f1 / (R1+R2)<-0.9。

[0022] Furthermore, the effective half-aperture DT52 of the image-side surface of the fifth lens and the effective half-aperture DT61 of the object-side surface of the sixth lens satisfy the following relationship: 1.2 <DT52 / DT61<1.7。

[0023] Furthermore, when the zoom lens is at its middle position, the air gap Dm2 between the third and fourth lenses on the optical axis and the center thickness CT3 of the third lens satisfy the following condition: 4.0 <Dm2 / CT3<7.2。

[0024] Furthermore, the effective focal length fm of the zoom lens when it is at the middle end, the air gap Dm1 between the first and second lenses on the optical axis when the zoom lens is at the middle end, and the air gap Dm2 between the third and fourth lenses on the optical axis when the zoom lens is at the middle end satisfy the following condition: 3.7 <fm / (Dm1+Dm2)<5.6。

[0025] Furthermore, the fifth lens is a glass lens, and the refractive index of the eighth lens is greater than 1.65.

[0026] According to another aspect of the present invention, there is provided a zoom lens, which sequentially includes, from the object side to the image side: a first lens group, the first lens group including a first lens having a positive optical power; a second lens group having a negative optical power, the second lens group including a second lens having a negative optical power and a third lens having a negative optical power; a third lens group having a positive optical power, the third lens group including a fourth lens having a positive optical power, a fifth lens having a positive optical power, a sixth lens having a negative optical power, a seventh lens having a negative optical power, and an eighth lens having a positive optical power; the second lens group and the third lens group are movably arranged on the optical axis, and continuous zoom of the zoom lens is achieved by adjusting the positions of the second lens group and the third lens group on the optical axis; when the zoom lens is at the wide-angle end, the following is satisfied between the effective focal length fw of the zoom lens and half of the maximum field angle Semi-FOV of the zoom lens at the wide-angle end: 31.5 < fw / tan(Semi-FOV) < 64.0; when the zoom lens is at the wide-angle end, the following is satisfied between the distance TTL on the optical axis from the object side surface of the first lens to the imaging surface and the effective focal length variable △f of the zoom lens at the telephoto end and the wide-angle end: 1.9 < TTL / △f < 2.6; the following is satisfied between the change value △D1 of the air gap on the optical axis between the first lens and the second lens when the zoom lens is switched from the wide-angle end to the telephoto end and the change value △D2 of the air gap on the optical axis between the third lens and the fourth lens when the zoom lens is switched from the wide-angle end to the telephoto end: 4.0 < |△D2 / △D1| < 5.2.

[0027] Further, the following is satisfied between the effective focal length FG2 of the second lens group and the effective focal length FG3 of the third lens group: -1.6 < FG3 / FG2 < -1.2.

[0028] Further, the following is satisfied between the effective focal length ft of the zoom lens at the telephoto end and the effective focal length f1 of the first lens: 1.6 < ft / f1 < 2.1.

[0029] Further, when the zoom lens is at the telephoto end, the following is satisfied between the distance TTL on the optical axis from the object side surface of the first lens to the imaging surface and the effective focal length ft of the zoom lens at the telephoto end: 0.9 < TTL / ft < 1.3.

[0030] Further, the following is satisfied between the radius of curvature R4 of the image side surface of the second lens and the radius of curvature R5 of the object side surface of the third lens: -7.3 < (R4 + R5) / (R4 - R5) < -6.8.

[0031] Further, the following is satisfied between the radius of curvature R7 of the object side surface of the fourth lens, the radius of curvature R8 of the image side surface of the fourth lens and the effective focal length f4 of the fourth lens: 0.9 < (R7 + R8) / f'style="font-family: Arial, Helvetica, sans-serif;">4 < 1.4. [[ID=Furthermore, the effective focal lengths of the third lens group (FG3), the fourth lens (f4), the fifth lens (f5), and the eighth lens (f8) satisfy the following condition: 4.4 < (f4 + f5 + f8) / FG3 < 5.3.

[0033] Furthermore, the radius of curvature R12 of the image side of the sixth lens and the radius of curvature R16 of the image side of the eighth lens satisfy the following condition: 0 < (R12 + R16) / R16 < 1.3.

[0034] Furthermore, when the zoom lens is at the wide-angle end, the air gap T12 between the first and second lenses on the optical axis, and the air gap T34 between the third and fourth lenses on the optical axis and the air gap T23 between the second and third lenses on the optical axis, satisfy the following condition: 4.5 < (T12 + T34) / T23 < 6.4.

[0035] Furthermore, the air gap T67 between the sixth and seventh lenses on the optical axis, the air gap T56 between the fifth and sixth lenses on the optical axis, and the center thickness CT5 of the fifth lens satisfy the following relationship: 0.7 <T67 / (T56+CT5)<2.2。

[0036] Furthermore, when the zoom lens is at the telephoto end, the distance TDt between the object-side surface of the first lens and the image-side surface of the eighth lens on the optical axis satisfies the following relationship between the air gap T67 between the sixth and seventh lenses on the optical axis: 2.8 <TDt / T67<4.9。

[0037] Furthermore, the air gaps T67 between the sixth and seventh lenses on the optical axis, T78 between the seventh and eighth lenses on the optical axis, T45 between the fourth and fifth lenses on the optical axis, and T56 between the fifth and sixth lenses on the optical axis satisfy the following condition: 2.0 < (T67 + T78) / (T45 + T56) < 4.8.

[0038] Furthermore, the effective focal length f1 of the first lens and the effective focal length f8 of the eighth lens satisfy the following relationship: 0.9 <f1 / f8<1.4。

[0039] Furthermore, the change in effective focal length Δf when the zoom lens is at the telephoto end and the wide-angle end, and the change in air gap ΔD2 of the third and fourth lenses on the optical axis when the zoom lens switches from the wide-angle end to the telephoto end, satisfy the following condition: 2.2 < Δf / ΔD2 < 2.8.

[0040] Furthermore, the center thickness CT1 of the first lens and the edge thickness ET1 at the maximum effective radius of the first lens satisfy: 2.1 <CT1 / ET1<3.7。

[0041] Furthermore, the distance SAG32 on the optical axis between the intersection point of the image-side surface of the third lens and the effective half-aperture of the image-side surface of the third lens, and the distance SAG21 on the optical axis between the intersection point of the object-side surface of the second lens and the effective half-aperture of the object-side surface of the second lens, satisfy the following condition: -2.7 <SAG32 / SAG21<-2.0。

[0042] Furthermore, the effective focal length f1 of the first lens, the radius of curvature R1 of the object-side surface of the first lens, and the radius of curvature R2 of the image-side surface of the first lens satisfy the following relationship: -1.5 <f1 / (R1+R2)<-0.9。

[0043] Furthermore, the effective half-aperture DT52 of the image-side surface of the fifth lens and the effective half-aperture DT61 of the object-side surface of the sixth lens satisfy the following relationship: 1.2 <DT52 / DT61<1.7。

[0044] Furthermore, when the zoom lens is at its middle position, the air gap Dm2 between the third and fourth lenses on the optical axis and the center thickness CT3 of the third lens satisfy the following condition: 4.0 <Dm2 / CT3<7.2。

[0045] Furthermore, the effective focal length fm of the zoom lens when it is at the middle end, the air gap Dm1 between the first and second lenses on the optical axis when the zoom lens is at the middle end, and the air gap Dm2 between the third and fourth lenses on the optical axis when the zoom lens is at the middle end satisfy the following condition: 3.7 <fm / (Dm1+Dm2)<5.6。

[0046] Furthermore, the fifth lens is a glass lens, and the refractive index of the eighth lens is greater than 1.65.

[0047] Applying the technical solution of the present invention, the zoom lens sequentially includes a first lens group, a second lens group with negative optical power, and a third lens group with positive optical power from the object side to the image side. The first lens group includes a first lens with positive optical power; the second lens group includes a second lens with negative optical power and a third lens with negative optical power; the third lens group includes a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with negative optical power, a seventh lens with negative optical power, and an eighth lens with positive optical power; the second lens group and the third lens group are movably arranged on the optical axis, and by adjusting the positions of the second lens group and the third lens group on the optical axis, continuous zooming of the zoom lens is achieved; when the zoom lens is at the wide-angle end, the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis satisfies: 1.9 < TTL / Δf < 2.6 with respect to the effective focal length variable Δf of the zoom lens at the telephoto end and the wide-angle end; the effective focal length FG2 of the second lens group and the effective focal length FG3 of the third lens group satisfy: -1.6 < FG3 / FG2 < -1.2; the effective focal length ft of the zoom lens at the telephoto end and the effective focal length f1 of the first lens satisfy: 1.6 < ft / f1 < 2.1.

[0048] The zoom lens of the present application consists of eight lenses from the first lens to the eighth lens. By reasonably matching the optical powers of each lens, the imaging quality of the entire zoom lens is ensured. By reasonably constraining the relationship between the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length variable Δf of the zoom lens at the telephoto end and the wide-angle end when the zoom lens is at the wide-angle end, the characteristics of high zoom of the zoom lens are guaranteed. By constraining the relationship between the effective focal length FG2 of the second lens group and the effective focal length FG3 of the third lens group at the wide-angle end, the continuous zooming ability of the zoom lens can be guaranteed. At the same time, the optical power of the first lens is distributed to improve the aberration of the system and obtain the best imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The schematic diagrams of the drawings forming a part of the present application are used to provide a further understanding of the present invention. The illustrative embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0050] Figures 1 to 3 The structural schematic diagrams of the zoom lens of Example 1 of the present invention at the wide-angle end, the middle end, and the telephoto end are respectively shown;

[0051] Figures 4 to 7 Are respectively shown Figure 1 The axial chromatic aberration curve, astigmatism curve, distortion curve, and lateral chromatic aberration curve of the zoom lens in at the wide-angle end;

[0052] Figures 8 to 11 Are respectively shown Figure 2 The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the zoom lens when it is at the middle end;

[0053] Figures 12 to 15 They are shown respectively Figure 3 The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the zoom lens at the telephoto end;

[0054] Figures 16 to 18 The following are schematic diagrams of the zoom lens of Example 2 of the present invention at the wide-angle end, the middle end, and the telephoto end;

[0055] Figures 19 to 22 They are shown respectively Figure 16 The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the zoom lens at the wide-angle end;

[0056] Figures 23 to 26 They are shown respectively Figure 17 The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the zoom lens when it is at the middle end;

[0057] Figures 27 to 30 They are shown respectively Figure 18 The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the zoom lens at the telephoto end;

[0058] Figures 31 to 33 Schematic diagrams of the zoom lens of Example 3 of the present invention are shown at the wide-angle end, the middle end, and the telephoto end, respectively.

[0059] Figures 34 to 37 They are shown respectively Figure 31 The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the zoom lens at the wide-angle end;

[0060] Figures 38 to 41 They are shown respectively Figure 32 The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the zoom lens when it is at the middle end;

[0061] Figures 42 to 45 They are shown respectively Figure 33 The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the zoom lens at the telephoto end;

[0062] Figures 46 to 48 Schematic diagrams of the zoom lens of Example 4 of the present invention at the wide-angle end, the middle end, and the telephoto end are shown respectively;

[0063] Figures 49 to 52 They are shown respectively Figure 46The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the zoom lens at the wide-angle end;

[0064] Figures 53 to 56 They are shown respectively Figure 47 The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the zoom lens when it is at the middle end;

[0065] Figures 57 to 60 They are shown respectively Figure 48 The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the zoom lens at the telephoto end;

[0066] Figures 61 to 63 The following are schematic diagrams of the zoom lens of Example 5 of the present invention at the wide-angle end, the intermediate end, and the telephoto end;

[0067] Figures 64 to 67 They are shown respectively Figure 61 On-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of a medium zoom lens at the wide-angle end;

[0068] Figures 68 to 71 They are shown respectively Figure 62 On-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of a medium zoom lens at the middle end;

[0069] Figures 72 to 75 They are shown respectively Figure 63 On-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of a medium zoom lens at the telephoto end;

[0070] Figures 76 to 78 The following are schematic diagrams of the zoom lens of Example Six of the present invention at the wide-angle end, the intermediate end, and the telephoto end;

[0071] Figures 79 to 82 They are shown respectively Figure 76 On-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of a medium zoom lens at the wide-angle end;

[0072] Figures 83 to 86 They are shown respectively Figure 77 On-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of a medium zoom lens at the middle end;

[0073] Figures 87 to 90 They are shown respectively Figure 78 On-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of a medium zoom lens at the telephoto end.

[0074] The above figures include the following reference numerals:

[0075] STO, Aperture Stop; G1, First Lens Group; G2, Second Lens Group; G3, Third Lens Group; E1, First Lens; S1, Object-side plane of the first lens; S2, Image-side plane of the first lens; E2, Second Lens; S3, Object-side plane of the second lens; S4, Image-side plane of the second lens; E3, Third Lens; S5, Object-side plane of the third lens; S6, Image-side plane of the third lens; E4, Fourth Lens; S7, Object-side plane of the fourth lens; S8, Image-side plane of the fourth lens; E5, Fifth Lens; S9, Object-side plane of the fifth lens; S10, Image-side plane of the fifth lens; E6, Sixth Lens; S11, Object-side plane of the sixth lens; S12, Image-side plane of the sixth lens; E7, Seventh Lens; S13, Object-side plane of the seventh lens; S14, Image-side plane of the seventh lens; E8, Eighth Lens; S15, Object-side plane of the eighth lens; S16, Image-side plane of the eighth lens; S17, Image plane. Detailed Implementation

[0076] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0077] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0078] In this invention, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" are generally used in relation to the direction shown in the accompanying drawings, or in relation to the vertical, perpendicular, or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0079] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of this application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0080] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not drawn strictly to scale.

[0081] In this text, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closer to the object side is the object side surface of the lens, and the surface of each lens closer to the image side is called the image side surface of the lens. The judgment of the surface shape in the paraxial region can be based on the judgment method of those with ordinary knowledge in this field, and the convexity and concavity are judged by the positive and negative values of the R value (R refers to the radius of curvature in the paraxial region, usually the R value on the lens database (lens data) in optical software). For the object side surface, when the R value is positive, it is judged as convex, and when the R value is negative, it is judged as concave; for the image side surface, when the R value is positive, it is judged as concave, and when the R value is negative, it is judged as convex.

[0082] To solve the problem that the existing zoom lenses are difficult to simultaneously achieve continuous zooming ability and high imaging quality, the present invention provides a zoom lens.

[0083] Embodiment 1

[0084] As Figures 1 to 90 shown, the zoom lens sequentially includes a first lens group, a second lens group with negative optical power, and a third lens group with positive optical power from the object side to the image side. The first lens group includes a first lens with positive optical power; the second lens group includes a second lens with negative optical power and a third lens with negative optical power; the third lens group includes a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with negative optical power, a seventh lens with negative optical power, and an eighth lens with positive optical power; the second lens group and the third lens group are movably arranged on the optical axis. By adjusting the positions of the second lens group and the third lens group on the optical axis, continuous zooming of the zoom lens is achieved; when the zoom lens is at the wide-angle end, the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length variable △f of the zoom lens at the telephoto end and the wide-angle end satisfy: 1.9 < TTL / △f < 2.6; the effective focal length FG2 of the second lens group and the effective focal length FG3 of the third lens group satisfy: -1.6 < FG3 / FG2 < -1.2; the effective focal length ft of the zoom lens at the telephoto end and the effective focal length f1 of the first lens satisfy: 1.6 < ft / f1 < 2.1.

[0085] The zoom lens of the present application consists of eight lenses from the first lens to the eighth lens. By reasonably matching the optical powers of each lens, the imaging quality of the entire zoom lens is ensured. By reasonably restricting the relationship between the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis when the zoom lens is at the wide-angle end and the effective focal length variable Δf of the zoom lens when it is at the telephoto end and the wide-angle end, the characteristics of high zoom of the zoom lens are guaranteed. By restricting the relationship between the effective focal length FG2 of the second lens group and the effective focal length FG3 of the third lens group at the wide-angle end, the continuous zoom ability of the zoom lens can be ensured. At the same time, the optical power of the first lens is distributed to improve the aberration of the system and obtain the best imaging quality.

[0086] In this embodiment, when the zoom lens is at the telephoto end, the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length ft of the zoom lens when it is at the telephoto end satisfy: 0.9 < TTL / ft < 1.3. Satisfying this conditional formula ensures that the effective focal length at the telephoto end and the distance from the object side surface of the first lens of the zoom lens to the imaging surface on the optical axis at the wide-angle end are within a certain range, so as to control the field angle within a certain range and prevent the aberration from increasing excessively, which helps to improve the image quality.

[0087] In this embodiment, the radius of curvature R4 of the image side surface of the second lens and the radius of curvature R5 of the object side surface of the third lens satisfy: -7.3 < (R4 + R5) / (R4 - R5) < -6.8. Satisfying this conditional formula restricts the radius of curvature of the image side surface of the second lens and the radius of curvature of the object side surface of the third lens within a certain range, which is beneficial to reducing the magnitude of optical distortion and ensuring better imaging quality.

[0088] In this embodiment, the radius of curvature R\(_7\) of the object side surface of the fourth lens, the radius of curvature R\(_8\) of the image side surface of the fourth lens and the effective focal length f\(_4\) of the fourth lens satisfy: 0.9 < (R\(_7\) + R\(_8\)) / f\(_4\) < 1.4. Satisfying this conditional formula restricts the radius of curvature of the object side surface of the fourth lens and the radius of curvature of the image side surface of the fourth lens within a certain range, which is beneficial to reducing the magnitude of optical distortion and ensuring better imaging quality.

[0089] In this embodiment, the effective focal length FG\(_3\) of the third lens group, the effective focal length f\(_4\) of the fourth lens, the effective focal length f\(_5\) of the fifth lens and the effective focal length f\(_8\) of the eighth lens satisfy: 4.4 < (f\(_4\) + f\(_5\) + f\(_8\)) / FG\(_3\) < 5.3. Satisfying this conditional formula is beneficial to reasonably distributing the optical power of the system and effectively improving the aberration of the system.

[0090] In this embodiment, the curvature radius R12 of the image side surface of the sixth lens and the curvature radius R16 of the image side surface of the eighth lens satisfy: 0 < (R12 + R16) / R16 < 1.3. Satisfying this conditional expression restricts the curvature radius of the image side surface of the sixth lens and the curvature radius of the image side surface of the eighth lens within a certain range, which is beneficial to reducing the magnitude of optical distortion and ensuring good imaging quality.

[0091] In this embodiment, when the zoom lens is at the wide-angle end, the air gap T12 between the first lens and the second lens on the optical axis, when the zoom lens is at the wide-angle end, the air gap T34 between the third lens and the fourth lens on the optical axis, and the air gap T23 between the second lens and the third lens on the optical axis satisfy: 4.5 < (T12 + T34) / T23 < 6.4. Satisfying this conditional expression rationally distributes the air intervals between the first lens, the second lens, the third lens, and the fourth lens on the optical axis, thereby effectively controlling the rear-end size of the zoom lens and avoiding excessive volume of the zoom lens.

[0092] In this embodiment, the change value △D1 of the air gap between the first lens and the second lens on the optical axis when the zoom lens switches from the wide-angle end to the telephoto end and the change value △D2 of the air gap between the third lens and the fourth lens on the optical axis when the zoom lens switches from the wide-angle end to the telephoto end satisfy: 4.0 < |△D2 / △D1| < 5.2. Satisfying this conditional expression controls the ratio of the change values of the air gaps between the first lens and the second lens and between the third lens and the fourth lens on the optical axis from the wide-angle end to the telephoto end within a certain range, which is beneficial to structural adjustment and layout and facilitates production.

[0093] In this embodiment, the air gap T67 between the sixth lens and the seventh lens on the optical axis, the air gap T56 between the fifth lens and the sixth lens on the optical axis, and the central thickness CT5 of the fifth lens satisfy: 0.7 < T67 / (T56 + CT5) < 2.2. Satisfying this conditional expression controls the ratio of the air gap between the sixth lens and the seventh lens on the optical axis to the air gap between the fifth lens and the sixth lens on the optical axis and the central thickness of the fifth lens, thereby effectively controlling the rear-end size of the zoom lens, avoiding excessive volume of the zoom lens, and being beneficial to structural adjustment and layout at the same time.

[0094] In this embodiment, when the zoom lens is at the telephoto end, the distance TDt on the optical axis from the object side surface of the first lens to the image side surface of the eighth lens satisfies 2.8 < TDt / T67 < 4.9 with respect to the air gap T67 on the optical axis between the sixth lens and the seventh lens. By satisfying this conditional formula, the ratio of the distance on the optical axis from the object side surface of the first lens to the image side surface of the eighth lens to the air gap on the optical axis between the sixth lens and the seventh lens at the telephoto end is controlled, thereby facilitating the setting of the gap between the sixth lens and the seventh lens, facilitating the structural adjustment and arrangement of the third lens group, and simultaneously controlling the overall length of the lens.

[0095] In this embodiment, the air gap T67 on the optical axis between the sixth lens and the seventh lens, the air gap T78 on the optical axis between the seventh lens and the eighth lens, the air gap T45 on the optical axis between the fourth lens and the fifth lens, and the air gap T56 on the optical axis between the fifth lens and the sixth lens satisfy 2.0 < (T67 + T78) / (T45 + T56) < 4.8. By satisfying this conditional formula, the air intervals on the optical axis of the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens are reasonably distributed, thereby effectively controlling the internal lens distribution of the zoom lens, enabling the lens group to have sufficient moving distance, and obtaining the best shooting quality.

[0096] In this embodiment, the effective focal length f1 of the first lens and the effective focal length f8 of the eighth lens satisfy 0.9 < f1 / f8 < 1.4. By satisfying this conditional formula, the optical powers of the first lens and the eighth lens are reasonably controlled, thereby effectively reducing the optical sensitivities of the first lens and the eighth lens, and being more conducive to realizing mass production.

[0097] In this embodiment, the change amount △f of the effective focal length when the zoom lens is at the telephoto end and the wide-angle end and the change value △D2 of the air gap on the optical axis between the third lens and the fourth lens when the zoom lens switches from the wide-angle end to the telephoto end satisfy 2.2 < △f / △D2 < 2.8. By satisfying this conditional formula, the ratio of the difference in the effective focal length of the zoom lens to the change value of the air gap on the optical axis between the third lens and the fourth lens from the wide-angle end to the telephoto end is controlled, thereby facilitating the control of the △D2 gap and ensuring the zoom change range.

[0098] In this embodiment, the central thickness CT1 of the first lens and the edge thickness ET1 at the maximum effective radius of the first lens satisfy 2.1 < CT1 / ET1 < 3.7. By satisfying this conditional formula, the ratio of the central thickness and the edge thickness of the first lens is reasonably controlled, which is beneficial to ensuring the molding process of the first lens.

[0099] In this embodiment, the distance SAG32 on the optical axis between the intersection of the image side surface of the third lens on the optical axis and the effective semi-aperture of the image side surface of the third lens and the distance SAG21 on the optical axis between the intersection of the object side surface of the second lens on the optical axis and the effective semi-aperture of the object side surface of the second lens satisfy: -2.7 < SAG32 / SAG21 < -2.0. Satisfying this conditional expression can reasonably distribute the image-side sagittal height of the third lens and the object-side sagittal height of the second lens, thereby reasonably controlling the main ray deflection angle, improving the matching degree with the chip, and facilitating the adjustment of the structure of the zoom lens.

[0100] In this embodiment, the effective focal length f1 of the first lens, the curvature radius R1 of the object side surface of the first lens, and the curvature radius R2 of the image side surface of the first lens satisfy: -1.5 < f1 / (R1 + R2) < -0.9. Satisfying this conditional expression can constrain the curvature radii of the object side surface and the image side surface of the first lens within a certain range, thereby effectively controlling the shape of the effective diameter region of the first lens and reducing the ghost image formed after the light passes through the first lens.

[0101] In this embodiment, the effective semi-aperture DT52 of the image side surface of the fifth lens and the effective semi-aperture DT61 of the object side surface of the sixth lens satisfy: 1.2 < DT52 / DT61 < 1.7. Satisfying this conditional expression can control the ratio of the effective semi-aperture on the image side of the fifth lens to the effective semi-aperture on the object side of the sixth lens, thereby reasonably controlling the effective diameter segment difference of the lens and the radial dimension of the lens, improving the matching degree with the chip, and at the same time facilitating the adjustment of the structure of the zoom lens.

[0102] In this embodiment, the air gap Dm2 on the optical axis between the third lens and the fourth lens when the zoom lens is at the intermediate end and the center thickness CT3 of the third lens satisfy: 4.0 < Dm2 / CT3 < 7.2. Satisfying this conditional expression can control the ratio of the air gap on the optical axis between the third lens and the fourth lens to the center thickness of the third lens when the zoom lens is at the intermediate end, thereby ensuring the spatial distribution of the second lens group in the lens, facilitating the focal length control of the second lens group, and achieving continuous zoom.

[0103] In this embodiment, the effective focal length fm when the zoom lens is at the intermediate end, the air gap Dm1 on the optical axis between the first lens and the second lens when the zoom lens is at the intermediate end, and the air gap Dm2 on the optical axis between the third lens and the fourth lens when the zoom lens is at the intermediate end satisfy: 3.7 < fm / (Dm1 + Dm2) < 5.6. Satisfying this conditional expression can ensure good imaging quality of the zoom lens at the intermediate end by controlling the relationship between the effective focal length at the intermediate end and the distances between the first lens and the second lens and between the third lens and the fourth lens on the optical axis. Controlling the gap can control the overall lens length and ensure that the total lens length during continuous zoom is not too long.

[0104] In this embodiment, the fifth lens is a glass lens, and the refractive index of the eighth lens is greater than 1.65. By selecting appropriate materials and restricting the dispersion coefficient, the thickness of the lens can be reduced, which can effectively control aberration and improve imaging quality.

[0105] Embodiment 2

[0106] As Figures 1 to 90 shown, the zoom lens sequentially includes, from the object side to the image side: a first lens group, the first lens group including a first lens with a positive optical power; a second lens group with a negative optical power, the second lens group including a second lens with a negative optical power and a third lens with a negative optical power; a third lens group with a positive optical power, the third lens group including a fourth lens with a positive optical power, a fifth lens with a positive optical power, a sixth lens with a negative optical power, a seventh lens with a negative optical power, and an eighth lens with a positive optical power; the second lens group and the third lens group are movably arranged on the optical axis, and by adjusting the positions of the second lens group and the third lens group on the optical axis, continuous zooming of the zoom lens is achieved; when the zoom lens is at the wide-angle end, the relationship between the effective focal length fw and half of the maximum field angle Semi-FOV of the zoom lens at the wide-angle end satisfies: 31.5 < fw / tan(Semi-FOV) < 64.0; when the zoom lens is at the wide-angle end, the relationship between the distance TTL on the optical axis from the object side surface of the first lens to the imaging surface and the change amount △f of the effective focal length of the zoom lens at the telephoto end and the wide-angle end satisfies: 1.9 < TTL / △f < 2.6; the change value △D1 of the air gap on the optical axis between the first lens and the second lens when the zoom lens switches from the wide-angle end to the telephoto end and the change value △D2 of the air gap on the optical axis between the third lens and the fourth lens when the zoom lens switches from the wide-angle end to the telephoto end satisfy: 4.0 < |△D2 / △D1| < 5.2.

[0107] The zoom lens of this application consists of eight lenses from the first lens to the eighth lens. By reasonably matching the optical powers of each lens, the imaging quality of the entire zoom lens is ensured and the aberration is reduced. By reasonably restricting the relationship between the effective focal length fw and half of the maximum field angle Semi-FOV when the zoom lens is at the wide-angle end and the relationship between the distance TTL on the optical axis from the object side surface of the first lens to the imaging surface and the change amount of the effective focal length of the zoom lens at the telephoto end and the wide-angle end, it is beneficial for the zoom lens to achieve the characteristics of telephoto and high zoom, and ensure that it still has good imaging quality during continuous zooming. At the same time, controlling the air gap Dm1 + Dm2 on the optical axis between each lens group in the zoom lens is beneficial for the adjustment and arrangement of the lens structure and is convenient for production.

[0108] Of course, other parameter formulas in the above embodiments may also be included in this embodiment, which will not be elaborated here one by one.

[0109] Optionally, the zoom lens may also include a color filter for correcting color deviation and a protective glass for protecting the image sensor located on the imaging surface.

[0110] The zoom lens in this application can employ multiple lenses, such as the eight lenses mentioned above. By rationally allocating the optical power, surface shape, center thickness of each lens, and on-axis distance between each lens, the sensitivity of the lens can be effectively reduced and the manufacturability of the lens can be improved, making the zoom lens more conducive to production and processing and suitable for portable electronic devices such as smartphones.

[0111] In this application, at least one of the mirror surfaces of each lens is an aspherical mirror surface. An aspherical lens is characterized by a continuously changing curvature from its center to its periphery. Unlike a spherical lens, which has a constant curvature from its center to its periphery, an aspherical lens has superior curvature radius characteristics, offering advantages in improving distortion and astigmatism. By using aspherical lenses, aberrations occurring during image formation can be eliminated as much as possible, thereby improving image quality.

[0112] Given that an aspherical surface is a structure obtained by rotating a curved surface in the meridional plane around the optical axis, this structure has rotational symmetry. In an ideal optical system, it can effectively correct aberrations in the meridional and sagittal planes. At the same time, its unique lens model can provide ample space for subsequent adjustments, allowing for more flexible structural and assembly processes without significantly reducing image quality.

[0113] However, those skilled in the art will understand that the number of lenses constituting the zoom lens can be changed without departing from the technical solutions claimed in this application to obtain the various results and advantages described in this specification. For example, although an eight-lens example has been described in the embodiments, the zoom lens is not limited to including eight lenses. If necessary, the zoom lens may also include other numbers of lenses.

[0114] The following description, with reference to the accompanying drawings, further illustrates examples of specific surface shapes and parameters of zoom lenses applicable to the above embodiments.

[0115] It should be noted that any of the examples one through six below are applicable to all embodiments of this application.

[0116] Example 1

[0117] like Figures 1 to 15 As shown, the zoom lens of Example 1 of this application is described. Figure 1 The diagram shows the structure of the zoom lens in Example 1 at the wide-angle end. Figure 2 The diagram shows the structure of the zoom lens in Example 1 when it is at the middle position. Figure 3The diagram shows the structure of the zoom lens in Example 1 when it is at the telephoto end.

[0118] like Figures 1 to 3 As shown, the zoom lens comprises, from the object side to the image side, a first lens group G1, a second lens group G2, and a third lens group G3. The first lens group G1 consists of a first lens E1. The second lens group G2 consists of a second lens E2 and a third lens E3 arranged sequentially from the object side to the image side. The third lens group G3 consists of a fourth lens E4, a fifth lens E5, an aperture stop STO, a sixth lens E6, a seventh lens E7, and an eighth lens E8 arranged sequentially from the object side to the image side.

[0119] The first lens E1 has positive optical power, with both its object-side surface S1 and image-side surface S2 being convex. The second lens E2 has negative optical power, with both its object-side surface S3 and image-side surface S4 being concave. The third lens E3 has negative optical power, with both its object-side surface S5 and image-side surface S6 being concave. The fourth lens E4 has positive optical power, with both its object-side surface S7 and image-side surface S8 being concave. The fifth lens E5 has positive optical power, with both its object-side surface S9 and image-side surface S10 being convex. The sixth lens E6 has negative optical power, with both its object-side surface S11 and image-side surface S12 being concave. The seventh lens E7 has negative optical power, with both its object-side surface S13 and image-side surface S14 being concave. The eighth lens E8 has positive optical power. The object-side surface S15 of the eighth lens is convex, and the image-side surface S16 of the eighth lens is also convex. Light from the object passes through each surface S1 to S16 in sequence and is finally imaged on the imaging surface S17.

[0120] In this example, the distance TTL between the object side of the first lens and the imaging plane on the optical axis when the zoom lens is at the wide-angle end, the intermediate end, and the telephoto end, the effective focal length f of the zoom lens, half of the maximum field of view (Semi-FOV) of the zoom lens, the aperture value FNO of the zoom lens, the distance D1 between the first lens and the second lens, the gap change D2 between the third lens and the fourth lens, and the gap change D3 between the eighth lens and the imaging plane satisfy the following Table 1.

[0121] TTL(mm) f(mm) Semi-FOV (°) FNO D1(mm) D2 (mm) D3(mm) Wide-angle end 25.31 11.94 17.2 2.4 0.642 5.265 0.725 middle end 25.03 16.88 11.9 2.8 1.227 2.816 2.308 telephoto end 25.26 23.86 8.4 3.1 1.709 0.549 4.330

[0122] Table 1

[0123] Table 2 shows the basic structural parameters of the zoom lens in Example 1, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0124]

[0125]

[0126] Table 2

[0127] In Example 1, the object-side surface and image-side surface of any one of the lenses from the first lens E1 to the eighth lens E8 are aspherical. The surface shape of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0128]

[0129] Where x is the distance vector from the vertex of the aspherical surface at a height h along the optical axis; c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above); k is the conic coefficient; Ai is the i-th order correction coefficient of the aspherical surface. Table 3 below gives the higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 that can be used for the aspherical mirrors S1-S16 in Example 1.

[0130]

[0131]

[0132] Table 3

[0133] Figure 4 The on-axis chromatic aberration curve of the zoom lens in Example 1 at the wide-angle end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 5 The astigmatism curve of the zoom lens in Example 1 at the wide-angle end is shown, which represents the meridional image plane curvature and the sagittal image plane curvature. Figure 6 The distortion curve of the zoom lens in Example 1 at the wide-angle end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 7 The magnification chromatic aberration curve of the zoom lens in Example 1 at the wide-angle end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0134] Figure 8 The on-axis chromatic aberration curve for Example 1 with the zoom lens at its middle position is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 9 The astigmatism curve of Example 1 when the zoom lens is at the middle end is shown, which represents the curvature of the meridional image plane and the curvature of the sagittal image plane. Figure 10 The distortion curve of the zoom lens in Example 1 at the middle position is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 11The magnification chromatic aberration curve for Example 1 when the zoom lens is at its middle position is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0135] Figure 12 The on-axis chromatic aberration curve of the zoom lens in Example 1 at the telephoto end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 13 The astigmatism curve of the zoom lens in Example 1 at the telephoto end is shown, which represents the curvature of the meridional image plane and the curvature of the sagittal image plane. Figure 14 The distortion curve of the zoom lens in Example 1 at the telephoto end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 15 The magnification chromatic aberration curve of the zoom lens in Example 1 at the telephoto end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0136] according to Figures 4 to 15 As can be seen, the zoom lens given in Example 1 can achieve good image quality.

[0137] Example 2

[0138] like Figures 16 to 30 As shown, the zoom lens of Example 2 of this application is described. Figure 16 The diagram shows the structure of the zoom lens in Example 2 at the wide-angle end. Figure 17 A schematic diagram of the structure of Example 2 with the zoom lens at the middle position is shown. Figure 18 The diagram shows the structure of the zoom lens in Example 2 when it is at the telephoto end.

[0139] like Figures 16 to 18 As shown, the zoom lens comprises, from the object side to the image side, a first lens group G1, a second lens group G2, and a third lens group G3. The first lens group G1 consists of a first lens E1. The second lens group G2 consists of a second lens E2 and a third lens E3 arranged sequentially from the object side to the image side. The third lens group G3 consists of a fourth lens E4, a fifth lens E5, an aperture stop STO, a sixth lens E6, a seventh lens E7, and an eighth lens E8 arranged sequentially from the object side to the image side.

[0140] The first lens E1 has positive optical power, with both its object-side surface S1 and image-side surface S2 being convex. The second lens E2 has negative optical power, with both its object-side surface S3 and image-side surface S4 being concave. The third lens E3 has negative optical power, with both its object-side surface S5 and image-side surface S6 being concave. The fourth lens E4 has positive optical power, with both its object-side surface S7 and image-side surface S8 being concave. The fifth lens E5 has positive optical power, with both its object-side surface S9 and image-side surface S10 being convex. The sixth lens E6 has negative optical power, with both its object-side surface S11 and image-side surface S12 being concave. The seventh lens E7 has negative optical power, with both its object-side surface S13 and image-side surface S14 being concave. The eighth lens E8 has positive optical power. The object-side surface S15 of the eighth lens is convex, and the image-side surface S16 of the eighth lens is also convex. Light from the object passes through each surface S1 to S16 in sequence and is finally imaged on the imaging surface S17.

[0141] In this example, the distance TTL between the object side of the first lens and the imaging plane on the optical axis when the zoom lens is at the wide-angle end, the intermediate end, and the telephoto end, the effective focal length f of the zoom lens, half of the maximum field of view (Semi-FOV) of the zoom lens, the aperture value FNO of the zoom lens, the distance D1 between the first lens and the second lens, the gap change D2 between the third lens and the fourth lens, and the gap change D3 between the eighth lens and the imaging plane satisfy the following Table 4.

[0142] TTL(mm) f(mm) Semi-FOV (°) FNO D1(mm) D2 (mm) D3(mm) Wide-angle end 30.33 14.15 14.4 2.4 0.9869 6.4446 0.7617 middle end 29.78 19.95 10.1 2.8 1.6491 3.4663 2.5298 telephoto end 29.84 28.15 7.1 3.1 2.1859 0.6982 4.8247

[0143] Table 4

[0144] Table 5 shows the basic structural parameters of the lens in Example 2, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0145]

[0146]

[0147] Table 5

[0148] Table 6 shows the higher-order coefficients that can be used for each aspherical mirror in Example 2, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0149]

[0150]

[0151] Table 6

[0152] Figure 19 The on-axis chromatic aberration curve of the zoom lens in Example 2 at the wide-angle end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 20 The astigmatism curve of the zoom lens in Example 2 at the wide-angle end is shown, which represents the meridional image plane curvature and the sagittal image plane curvature. Figure 21 The distortion curve of the zoom lens in Example 2 at the wide-angle end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 22 The magnification chromatic aberration curve of Example 2 when the zoom lens is at the wide-angle end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0153] Figure 23 The on-axis chromatic aberration curve for Example 2 with the zoom lens at its middle position is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 24 The astigmatism curve for Example 2 when the zoom lens is at the middle end is shown, which represents the curvature of the meridional image plane and the curvature of the sagittal image plane. Figure 25 The distortion curve of the zoom lens in Example 2 at the middle position is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 26 The magnification chromatic aberration curve for Example 2 when the zoom lens is at the middle position is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0154] Figure 27 The on-axis chromatic aberration curve of the zoom lens in Example 2 at the telephoto end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 28 The astigmatism curve of the zoom lens in Example 2 at the telephoto end is shown, which represents the curvature of the meridional image plane and the curvature of the sagittal image plane. Figure 29 The distortion curve of the zoom lens in Example 2 at the telephoto end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 30 The magnification chromatic aberration curve of the zoom lens in Example 2 at the telephoto end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0155] according to Figures 19 to 30 As can be seen, the zoom lens given in Example 2 can achieve good image quality.

[0156] Example 3

[0157] like Figures 31 to 45 As shown, the zoom lens of Example 3 of this application is described. Figure 31 A schematic diagram of the zoom lens in Example 3 at the wide-angle end is shown. Figure 32 The diagram shows the structure of Example 3 when the zoom lens is at the middle position. Figure 33A schematic diagram of the structure of the zoom lens in Example 3 when it is at the telephoto end is shown.

[0158] like Figures 31 to 33 As shown, the zoom lens comprises, from the object side to the image side, a first lens group G1, a second lens group G2, and a third lens group G3. The first lens group G1 consists of a first lens E1. The second lens group G2 consists of a second lens E2 and a third lens E3 arranged sequentially from the object side to the image side. The third lens group G3 consists of a fourth lens E4, a fifth lens E5, an aperture stop STO, a sixth lens E6, a seventh lens E7, and an eighth lens E8 arranged sequentially from the object side to the image side.

[0159] The first lens E1 has positive optical power, with both its object-side surface S1 and image-side surface S2 being convex. The second lens E2 has negative optical power, with both its object-side surface S3 and image-side surface S4 being concave. The third lens E3 has negative optical power, with both its object-side surface S5 and image-side surface S6 being concave. The fourth lens E4 has positive optical power, with both its object-side surface S7 and image-side surface S8 being concave. The fifth lens E5 has positive optical power, with both its object-side surface S9 and image-side surface S10 being convex. The sixth lens E6 has negative optical power, with both its object-side surface S11 and image-side surface S12 being concave. The seventh lens E7 has negative optical power, with both its object-side surface S13 and image-side surface S14 being concave. The eighth lens E8 has positive optical power. The object-side surface S15 of the eighth lens is convex, and the image-side surface S16 of the eighth lens is also convex. Light from the object passes through each surface S1 to S16 in sequence and is finally imaged on the imaging surface S17.

[0160] In this example, the distance TTL between the object side of the first lens and the imaging plane on the optical axis when the zoom lens is at the wide-angle end, the intermediate end, and the telephoto end, the effective focal length f of the zoom lens, half of the maximum field of view (Semi-FOV) of the zoom lens, the aperture value FNO of the zoom lens, the distance D1 between the first lens and the second lens, the gap change D2 between the third lens and the fourth lens, and the gap change D3 between the eighth lens and the imaging plane satisfy the following Table 7.

[0161] TTL(mm) f(mm) Semi-FOV (°) FNO D1(mm) D2 (mm) D3(mm) Wide-angle end 32.67 15.20 13.4 2.4 1.1529 6.8228 0.6973 middle end 31.92 21.48 9.3 2.6 1.8497 3.5850 2.4923 telephoto end 31.90 30.37 6.6 3.1 2.3761 0.6056 4.9338

[0162] Table 7

[0163] Table 8 shows the basic structural parameters of the three lenses in Example 3, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0164]

[0165] Table 8

[0166] Table 9 shows the higher-order coefficients that can be used for each aspherical mirror in Example 3, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0167] Face number A4 A6 A8 A10 A12 A14 A16 S1 -4.81E-02 -1.08E-02 -5.32E-03 -1.92E-03 -6.35E-04 -2.45E-04 -4.35E-05 S2 4.76E-02 -8.04E-03 -3.18E-03 -7.86E-04 -2.56E-04 -9.28E-05 8.32E-06 S3 -4.25E-02 -6.82E-02 3.89E-02 -1.56E-02 4.33E-03 -1.07E-03 1.27E-04 S4 6.29E-01 -1.39E-01 4.41E-02 -9.28E-03 7.74E-04 -1.19E-04 -1.72E-04 S5 1.63E-01 -4.56E-02 1.99E-02 -3.00E-05 -1.45E-06 1.42E-04 5.63E-05 S6 -8.80E-01 -6.08E-03 -6.34E-04 8.02E-07 -5.29E-05 6.11E-05 4.75E-05 S7 -2.01E-01 -1.50E-02 -2.83E-02 -1.57E-02 -4.54E-03 -3.18E-04 -1.23E-04 S8 -2.58E-02 7.22E-05 -2.56E-02 -2.30E-02 1.73E-03 1.30E-03 3.30E-04 S9 -1.16E-01 -4.40E-02 6.84E-03 -8.34E-03 5.56E-03 1.64E-03 5.61E-04 S10 4.19E-03 -3.50E-02 1.17E-02 -1.24E-03 6.84E-04 7.97E-04 9.32E-05 S11 1.84E-01 -4.10E-03 4.69E-03 -9.84E-04 1.95E-04 6.36E-05 1.63E-05 S12 2.17E-01 4.62E-03 3.21E-03 -3.49E-04 3.74E-05 1.77E-05 8.98E-06 S13 -4.91E-01 1.98E-01 -2.62E-02 -4.62E-03 -7.53E-04 4.45E-04 -1.50E-03 S14 -2.49E+00 8.45E-02 -9.35E-02 -1.13E-02 -3.09E-02 -1.06E-02 -1.05E-02 S15 1.62E-01 6.77E-02 -4.88E-02 2.30E-02 -3.13E-03 1.07E-03 -7.28E-03 S16 3.92E-01 -3.38E-02 -3.10E-02 2.22E-02 1.43E-02 5.34E-03 -1.12E-03 Face number A18 A20 A22 A24 A26 A28 A30 S1 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S2 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S3 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S4 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S5 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S6 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S7 -5.53E-05 -8.91E-06 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S8 -3.86E-05 -2.25E-05 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S9 7.13E-05 1.64E-05 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S10 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S11 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S12 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S13 -1.03E-03 -5.26E-04 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S14 -2.60E-03 -1.49E-03 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S15 -2.07E-03 -1.32E-03 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S16 -1.07E-03 -4.63E-04 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

[0168] Table 9

[0169] Figure 34 The on-axis chromatic aberration curve of the zoom lens in Example 3 at the wide-angle end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 35 The astigmatism curve of Example 3 when the zoom lens is at the wide-angle end is shown, which represents the meridional image plane curvature and the sagittal image plane curvature. Figure 36 The distortion curve of the zoom lens in Example 3 at the wide-angle end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 37 The magnification chromatic aberration curve of Example 3 when the zoom lens is at the wide-angle end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0170] Figure 38 The on-axis chromatic aberration curve for Example 3 with the zoom lens at its midpoint is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 39 The astigmatism curve of Example 3 when the zoom lens is at the middle end is shown, which represents the curvature of the meridional image plane and the curvature of the sagittal image plane. Figure 40 The distortion curve of the zoom lens in Example 3 at the middle position is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 41 The magnification chromatic aberration curve for Example 3 when the zoom lens is at the middle position is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0171] Figure 42 The on-axis chromatic aberration curve of the zoom lens in Example 3 at the telephoto end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 43 The astigmatism curve of Example 3 when the zoom lens is at the telephoto end is shown, which represents the meridional image plane curvature and the sagittal image plane curvature. Figure 44 The distortion curve of the zoom lens in Example 3 at the telephoto end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 45 The magnification chromatic aberration curve of Example 3 when the zoom lens is at the telephoto end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0172] according to Figures 34 to 45 As can be seen, the zoom lens given in Example 3 can achieve good image quality.

[0173] Example 4

[0174] like Figures 46 to 60 As shown, the zoom lens of Example 4 of this application is described. Figure 46 A schematic diagram of the zoom lens in Example 4 at the wide-angle end is shown. Figure 47 A schematic diagram of the structure of Example 4 with the zoom lens at the middle position is shown. Figure 48 The diagram shows the structure of Example 4 when the zoom lens is at the telephoto end.

[0175] like Figures 46 to 48 As shown, the zoom lens comprises, from the object side to the image side, a first lens group G1, a second lens group G2, and a third lens group G3. The first lens group G1 consists of a first lens E1. The second lens group G2 consists of a second lens E2 and a third lens E3 arranged sequentially from the object side to the image side. The third lens group G3 consists of a fourth lens E4, a fifth lens E5, an aperture stop STO, a sixth lens E6, a seventh lens E7, and an eighth lens E8 arranged sequentially from the object side to the image side.

[0176] The first lens E1 has positive optical power, with both its object-side surface S1 and image-side surface S2 being convex. The second lens E2 has negative optical power, with both its object-side surface S3 and image-side surface S4 being concave. The third lens E3 has negative optical power, with both its object-side surface S5 and image-side surface S6 being concave. The fourth lens E4 has positive optical power, with both its object-side surface S7 and image-side surface S8 being concave. The fifth lens E5 has positive optical power, with both its object-side surface S9 and image-side surface S10 being convex. The sixth lens E6 has negative optical power, with both its object-side surface S11 and image-side surface S12 being convex. The seventh lens E7 has negative optical power, with both its object-side surface S13 and image-side surface S14 being concave. The eighth lens E8 has positive optical power. The object-side surface S15 of the eighth lens is convex, and the image-side surface S16 of the eighth lens is also convex. Light from the object passes through each surface S1 to S16 in sequence and is finally imaged on the imaging surface S17.

[0177] In this example, the distance TTL between the object side of the first lens and the imaging plane on the optical axis when the zoom lens is at the wide-angle end, the intermediate end, and the telephoto end, the effective focal length f of the zoom lens, half of the maximum field of view (Semi-FOV) of the zoom lens, the aperture value FNO of the zoom lens, the distance D1 between the first lens and the second lens, the gap change D2 between the third lens and the fourth lens, and the gap change D3 between the eighth lens and the imaging plane satisfy the following Table 10.

[0178] TTL(mm) f(mm) Semi-FOV (°) FNO D1(mm) D2 (mm) D3(mm) Wide-angle end 24.07 11.76 17.5 2.4 0.6162 3.8838 0.4600 middle end 23.77 16.00 12.7 2.8 1.0914 1.8356 1.7424 telephoto end 23.92 21.30 9.5 3.1 1.4437 0.1109 3.2813

[0179] Table 10

[0180] Table 11 shows the basic structural parameters of the four lenses in the example, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0181]

[0182] Table 11

[0183] Table 12 shows the higher-order coefficients that can be used for each aspherical mirror in Example 4, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0184]

[0185]

[0186] Table 12

[0187] Figure 49 The on-axis chromatic aberration curve of Example 4 when the zoom lens is at the wide-angle end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 50 The astigmatism curves of Example 4 when the zoom lens is at the wide-angle end are shown, which represent the meridional image plane curvature and the sagittal image plane curvature. Figure 51 The distortion curve of the zoom lens in Example 4 at the wide-angle end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 52 The magnification chromatic aberration curve for Example 4 when the zoom lens is at the wide-angle end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0188] Figure 53 The on-axis chromatic aberration curve for Example 4 with the zoom lens at its midpoint is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 54 The astigmatism curves for Example 4 when the zoom lens is at the middle end are shown, representing the meridional image plane curvature and the sagittal image plane curvature. Figure 55 The distortion curve of the zoom lens in Example 4 at the middle position is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 56 The magnification chromatic aberration curve for Example 4 with the zoom lens at the middle position is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0189] Figure 57 The on-axis chromatic aberration curve of Example 4 when the zoom lens is at the telephoto end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 58 The astigmatism curves of Example 4 when the zoom lens is at the telephoto end are shown, which represent the curvature of the meridional image plane and the curvature of the sagittal image plane. Figure 59 The distortion curve of the zoom lens in Example 4 at the telephoto end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 60 The magnification chromatic aberration curve for Example 4 when the zoom lens is at the telephoto end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0190] according to Figures 49 to 60 As can be seen, the zoom lens given in Example 4 can achieve good image quality.

[0191] Example 5

[0192] like Figures 61 to 75 As shown, the zoom lens of Example 5 of this application is described. Figure 61 A schematic diagram of the structure of Example 5 when the zoom lens is at the wide-angle end is shown. Figure 62 A schematic diagram of the structure of Example 5 when the zoom lens is at the middle end is shown. Figure 63 The diagram shows the structure of Example 5 when the zoom lens is at the telephoto end.

[0193] like Figures 61 to 63 As shown, the zoom lens comprises, from the object side to the image side, a first lens group G1, a second lens group G2, and a third lens group G3. The first lens group G1 consists of a first lens E1. The second lens group G2 consists of a second lens E2 and a third lens E3 arranged sequentially from the object side to the image side. The third lens group G3 consists of a fourth lens E4, a fifth lens E5, an aperture stop STO, a sixth lens E6, a seventh lens E7, and an eighth lens E8 arranged sequentially from the object side to the image side.

[0194] The first lens E1 has positive optical power, with both its object-side surface S1 and image-side surface S2 being convex. The second lens E2 has negative optical power, with both its object-side surface S3 and image-side surface S4 being concave. The third lens E3 has negative optical power, with both its object-side surface S5 and image-side surface S6 being concave. The fourth lens E4 has positive optical power, with both its object-side surface S7 and image-side surface S8 being concave. The fifth lens E5 has positive optical power, with both its object-side surface S9 and image-side surface S10 being convex. The sixth lens E6 has negative optical power, with both its object-side surface S11 and image-side surface S12 being convex. The seventh lens E7 has negative optical power, with both its object-side surface S13 and image-side surface S14 being concave. The eighth lens E8 has positive optical power. The object-side surface S15 of the eighth lens is convex, and the image-side surface S16 of the eighth lens is concave. Light from the object passes through each surface S1 to S16 in sequence and is finally imaged on the imaging surface S17.

[0195] In this example, the distance TTL between the object side of the first lens and the imaging plane on the optical axis when the zoom lens is at the wide-angle end, the intermediate end, and the telephoto end, the effective focal length f of the zoom lens, half of the maximum field of view (Semi-FOV) of the zoom lens, the aperture value FNO of the zoom lens, the distance D1 between the first lens and the second lens, the gap change D2 between the third lens and the fourth lens, and the gap change D3 between the eighth lens and the imaging plane satisfy the following Table 13.

[0196] TTL(mm) f(mm) Semi-FOV (°) FNO D1(mm) D2 (mm) D3(mm) Wide-angle end 26.73 12.93 15.8 2.4 0.7212 4.2981 0.4469 middle end 26.31 17.60 11.4 2.8 1.2432 2.0317 1.7731 telephoto end 26.38 23.43 8.6 3.1 1.6064 0.1186 3.4168

[0197] Table 13

[0198] Table 14 shows the basic structural parameters of the lens in Example 5, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0199]

[0200]

[0201] Table 14

[0202] Table 15 shows the higher-order coefficients that can be used for each aspherical mirror in Example 5, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0203]

[0204]

[0205] Table 15

[0206] Figure 64 The on-axis chromatic aberration curve of Example 5 when the zoom lens is at the wide-angle end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 65 The astigmatism curves of Example 5 when the zoom lens is at the wide-angle end are shown, representing the meridional image plane curvature and the sagittal image plane curvature. Figure 66 The distortion curve of the zoom lens in Example 5 at the wide-angle end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 67 The magnification chromatic aberration curve for Example 5 when the zoom lens is at the wide-angle end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0207] Figure 68 The on-axis chromatic aberration curve for Example 5 with the zoom lens at its midpoint is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 69 The astigmatism curves for Example 5 when the zoom lens is at the middle end are shown, representing the meridional image plane curvature and the sagittal image plane curvature. Figure 70The distortion curve of the zoom lens in Example 5 at the middle end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 71 The magnification chromatic aberration curve for Example 5 when the zoom lens is at the middle position is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0208] Figure 72 The on-axis chromatic aberration curve of Example 5 when the zoom lens is at the telephoto end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 73 The astigmatism curve of Example 5 when the zoom lens is at the telephoto end is shown, which represents the meridional image plane curvature and the sagittal image plane curvature. Figure 74 The distortion curve of the zoom lens in Example 5 at the telephoto end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 75 The magnification chromatic aberration curve of Example 5 when the zoom lens is at the telephoto end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0209] according to Figures 64 to 75 As can be seen, the zoom lens given in Example 5 can achieve good image quality.

[0210] Example 6

[0211] like Figures 76 to 90 As shown, a zoom lens of Example Six of this application is described. Figure 76 A schematic diagram of the zoom lens in Example 6 at the wide-angle end is shown. Figure 77 A schematic diagram of the structure of Example 6 with the zoom lens at the middle position is shown. Figure 78 The diagram shows the structure of Example Six when the zoom lens is at the telephoto end.

[0212] like Figures 76 to 78 As shown, the zoom lens comprises, from the object side to the image side, a first lens group G1, a second lens group G2, and a third lens group G3. The first lens group G1 consists of a first lens E1. The second lens group G2 consists of a second lens E2 and a third lens E3 arranged sequentially from the object side to the image side. The third lens group G3 consists of a fourth lens E4, a fifth lens E5, an aperture stop STO, a sixth lens E6, a seventh lens E7, and an eighth lens E8 arranged sequentially from the object side to the image side.

[0213] The first lens E1 has positive optical power, with both its object-side surface S1 and image-side surface S2 being convex. The second lens E2 has negative optical power, with both its object-side surface S3 and image-side surface S4 being concave. The third lens E3 has negative optical power, with both its object-side surface S5 and image-side surface S6 being concave. The fourth lens E4 has positive optical power, with both its object-side surface S7 and image-side surface S8 being concave. The fifth lens E5 has positive optical power, with both its object-side surface S9 and image-side surface S10 being convex. The sixth lens E6 has negative optical power, with both its object-side surface S11 and image-side surface S12 being concave. The seventh lens E7 has negative optical power, with both its object-side surface S13 and image-side surface S14 being concave. The eighth lens E8 has positive optical power. The object-side surface S15 of the eighth lens is convex, and the image-side surface S16 of the eighth lens is also convex. Light from the object passes through each surface S1 to S16 in sequence and is finally imaged on the imaging surface S17.

[0214] In this example, the distance TTL between the object side of the first lens and the imaging plane on the optical axis when the zoom lens is at the wide-angle end, the intermediate end, and the telephoto end, the effective focal length f of the zoom lens, half of the maximum field of view (Semi-FOV) of the zoom lens, the aperture value FNO of the zoom lens, the distance D1 between the first lens and the second lens, the gap change D2 between the third lens and the fourth lens, and the gap change D3 between the eighth lens and the imaging plane satisfy the following Table 16.

[0215] TTL(mm) f(mm) Semi-FOV (°) FNO D1(mm) D2 (mm) D3(mm) Wide-angle end 22.45 10.85 18.8 2.4 0.5562 4.5327 0.9949 middle end 22.45 15.35 13.2 2.8 0.8941 2.4448 2.7361 telephoto end 22.45 21.69 9.2 3.1 1.5313 0.5000 4.0572

[0216] Table 16

[0217] Table 17 shows the basic structural parameters of the lens in Example Six, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0218]

[0219] Table 17

[0220] Table 18 shows the higher-order coefficients that can be used for each aspherical mirror in Example 6, wherein each aspherical surface type can be defined by formula (1) given in Example 1 above.

[0221] Face number A4 A6 A8 A10 A12 A14 A16 S1 -3.03E-02 -7.28E-03 -3.54E-03 -1.44E-03 -4.61E-04 -2.17E-04 -5.17E-05 S2 3.01E-02 -5.25E-03 -1.88E-03 -6.17E-04 -1.37E-04 -1.01E-04 1.62E-06 S3 -2.75E-02 -4.47E-02 2.51E-02 -9.69E-03 2.66E-03 -6.33E-04 7.15E-05 S4 4.04E-01 -9.04E-02 2.83E-02 -5.28E-03 6.14E-04 -4.18E-05 -1.08E-04 S5 1.05E-01 -2.90E-02 1.31E-02 1.79E-04 1.92E-04 -5.96E-05 -1.15E-05 S6 -5.65E-01 -3.36E-03 9.11E-05 7.62E-05 1.28E-04 -4.48E-05 8.66E-06 S7 -1.30E-01 -8.58E-03 -1.84E-02 -1.01E-02 -2.69E-03 -2.11E-04 -2.99E-05 S8 -1.59E-02 -6.25E-04 -1.63E-02 -1.48E-02 1.15E-03 9.08E-04 3.72E-04 S9 -7.61E-02 -2.79E-02 4.59E-03 -5.51E-03 3.40E-03 1.41E-03 6.69E-04 S10 2.93E-03 -2.24E-02 7.15E-03 -6.99E-04 4.23E-04 7.23E-04 9.43E-05 S11 1.18E-01 -3.27E-03 3.12E-03 -4.86E-04 2.86E-05 1.28E-04 2.73E-06 S12 1.40E-01 2.46E-03 2.07E-03 -1.01E-04 -5.99E-05 4.18E-05 8.69E-06 S13 -4.41E-01 1.41E-01 -9.52E-03 -2.77E-03 -2.04E-03 -2.50E-05 -9.31E-04 S14 -1.57E+00 7.45E-02 -7.00E-02 -2.94E-03 -2.33E-02 -5.41E-03 -6.16E-03 S15 -2.98E-04 8.16E-02 -4.04E-02 2.18E-02 -7.15E-03 1.21E-03 -3.90E-03 S16 2.10E-01 4.49E-02 -3.35E-02 1.40E-02 8.39E-03 4.95E-03 1.77E-04 Face number A18 A20 A22 A24 A26 A28 A30 S1 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S2 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S3 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S4 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S5 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S6 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S7 -6.32E-05 -2.45E-05 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S8 -1.66E-04 2.74E-05 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S9 -9.54E-06 8.52E-05 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S10 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S11 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S12 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S13 -1.50E-04 -3.05E-04 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S14 -1.82E-03 -1.28E-03 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S15 -2.18E-03 -1.12E-03 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 S16 -7.34E-04 -4.69E-04 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

[0222] Table 18

[0223] Figure 79 The on-axis chromatic aberration curve of Example Six when the zoom lens is at the wide-angle end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 80The astigmatism curves of Example Six when the zoom lens is at the wide-angle end are shown, representing the meridional image plane curvature and the sagittal image plane curvature. Figure 81 The distortion curve of the zoom lens in Example 6 at the wide-angle end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 82 The magnification chromatic aberration curve of Example Six when the zoom lens is at the wide-angle end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0224] Figure 83 The on-axis chromatic aberration curve for Example Six is ​​shown when the zoom lens is at its middle position, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 84 The astigmatism curve of Example Six when the zoom lens is at the middle end is shown, which represents the meridional image plane curvature and the sagittal image plane curvature. Figure 85 The distortion curve of the zoom lens in Example 6 is shown when it is at the middle end, which represents the distortion magnitude value corresponding to different field of view angles. Figure 86 The magnification chromatic aberration curve for Example Six when the zoom lens is at its middle position is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0225] Figure 87 The on-axis chromatic aberration curve of Example Six when the zoom lens is at the telephoto end is shown, which indicates the deflection of the focal point of light of different wavelengths after passing through the zoom lens. Figure 88 The astigmatism curve of Example Six when the zoom lens is at the telephoto end is shown, which represents the meridional image plane curvature and the sagittal image plane curvature. Figure 89 The distortion curve of the zoom lens in Example 6 at the telephoto end is shown, which represents the distortion magnitude corresponding to different field of view angles. Figure 90 The magnification chromatic aberration curve of Example Six when the zoom lens is at the telephoto end is shown, which represents the deviation of light at different image heights on the imaging plane after passing through the zoom lens.

[0226] according to Figures 79 to 90 As can be seen, the zoom lens given in Example 6 can achieve good image quality.

[0227] In summary, Examples 1 through 6 satisfy the relationships shown in Table 19.

[0228] Conditional expressions / examples one two three Four five six FG3 / FG2 -1.54 -1.53 -1.47 -1.33 -1.31 -1.41 TTL / △f 2.12 2.17 2.15 2.52 2.55 2.07 ft / f1 2.03 2.02 2.02 1.77 1.80 2.02 TTL / ft 1.06 1.06 1.05 1.12 1.13 1.03 (R4+R5) / (R4-R5) -7.16 -7.11 -6.98 -6.94 -6.96 -7.11 (R7+R8) / f4 1.31 1.32 1.32 1.09 1.10 1.34 (f4+f5+f8) / FG3 4.59 4.53 4.70 5.19 5.22 5.11 (R12+R16) / R16 0.23 0.48 0.88 1.12 0.95 0.61 (T12+T34) / T23 5.85 6.24 6.24 4.65 4.67 5.54 |△D2 / △D1| 4.42 4.79 5.08 4.56 4.72 4.14 T67 / (T56+CT5) 1.94 1.99 2.07 0.88 1.00 1.81 TDt / T67 2.99 2.99 2.94 4.77 4.47 2.99 (T67+T78) / (T45+T56) 4.25 4.36 4.69 2.32 2.26 3.87 f1 / f8 1.14 1.21 1.23 1.16 1.17 1.05 △f / △D2 2.53 2.44 2.44 2.53 2.51 2.69 CT1 / ET1 2.95 2.68 3.36 2.61 2.30 3.50 SAG32 / SAG21 -2.26 -2.53 -2.30 -2.35 -2.45 -2.12 f1 / (R1+R2) -1.31 -1.34 -1.35 -1.07 -1.15 -1.25 DT52 / DT61 1.39 1.39 1.36 1.50 1.50 1.41 Dm2 / CT3 7.08 7.03 6.39 4.23 4.21 6.99 fm / (Dm1+Dm2) 4.18 3.90 3.95 5.47 5.38 4.60 fw / tan(Semi-FOV) 38.46 54.93 63.85 37.34 45.70 31.86

[0229] Table 19

[0230] Table 20 gives the effective focal lengths f1 to f8 of each lens in Examples 1 to 6, as well as the effective focal lengths FG2 of the second lens group and FG3 of the third lens group.

[0231] Optical parameters / examples one two three Four five six f1(mm) 11.77 13.90 15.01 12.01 13.03 10.73 f2 (mm) -8.73 -10.35 -11.12 -8.87 -9.58 -8.04 f3 (mm) -13.98 -16.44 -17.84 -14.02 -15.56 -12.47 f4 (mm) 16.82 19.90 21.47 17.36 18.91 15.17 f5 (mm) 8.27 9.77 10.51 7.17 7.84 7.56 f6 (mm) -13.70 -15.61 -17.00 -11.42 -12.07 -12.78 f7 (mm) -10.55 -12.02 -12.68 -10.98 -11.91 -9.53 f8(mm) 10.34 11.52 12.23 10.36 11.14 10.23 FG2(mm) -5.02 -5.93 -6.39 -5.07 -5.54 -4.57 FG3 (mm) 7.71 9.09 9.40 6.73 7.25 6.45

[0232] Table 20

[0233] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0234] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0235] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0236] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A zoom lens, characterized in that, From the object side to the image side, the following are included in sequence: The first lens group includes a first lens with positive optical power, and the total number of lenses with optical power in the first lens group is 1. A second lens group with negative optical power, the second lens group including a second lens with negative optical power and a third lens with negative optical power, the total number of lenses with optical power in the second lens group is 2; A third lens group with positive optical power, the third lens group including a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with negative optical power, a seventh lens with negative optical power, and an eighth lens with positive optical power, the total number of lenses with optical power in the third lens group is 5. The zoom lens has a total of 3 lens groups with optical power. The first lens has a convex object-side surface and a convex image-side surface; the second lens has a concave object-side surface and a concave image-side surface; the third lens has a convex object-side surface and a concave image-side surface; the fourth lens has a convex object-side surface and a concave image-side surface; the fifth lens has a convex object-side surface and a convex image-side surface; the sixth lens has a concave object-side surface; the seventh lens has a convex object-side surface and a concave image-side surface; and the eighth lens has a convex object-side surface. The second lens group and the third lens group are movably arranged on the optical axis. By adjusting the positions of the second lens group and the third lens group on the optical axis, continuous zoom of the zoom lens can be achieved. When the zoom lens is at the wide-angle end, the distance TTL from the object side of the first lens to the imaging plane on the optical axis satisfies the following condition with respect to the effective focal length variable Δf when the zoom lens is at the telephoto end and the wide-angle end: 2.07≤TTL / Δf<2.6; The effective focal length FG2 of the second lens group and the effective focal length FG3 of the third lens group satisfy the following condition: -1.54 ≤ FG3 / FG2 ≤ -1.31; The effective focal length ft of the zoom lens at the telephoto end satisfies the following relationship with the effective focal length f1 of the first lens: 1.77≤ft / f1≤2.

03.

2. The zoom lens according to claim 1, characterized in that, When the zoom lens is at the telephoto end, the distance TTL from the object side of the first lens to the imaging surface on the optical axis satisfies the following condition with respect to the effective focal length ft of the zoom lens at the telephoto end: 1.03≤TTL / ft≤1.

13.

3. The zoom lens according to claim 1, characterized in that, The radius of curvature R4 of the image side of the second lens and the radius of curvature R5 of the object side of the third lens satisfy the following condition: -7.16≤(R4+R5) / (R4-R5)≤-6.

94.

4. The zoom lens according to claim 1, characterized in that, The radius of curvature R7 of the object side of the fourth lens, the radius of curvature R8 of the image side of the fourth lens, and the effective focal length f4 of the fourth lens satisfy the following condition: 1.09≤(R7+R8) / f4≤1.

34.

5. The zoom lens according to claim 1, characterized in that, The effective focal lengths of the third lens group (FG3), the fourth lens (f4), the fifth lens (f5), and the eighth lens (f8) satisfy the following condition: 4.53 ≤ (f4 + f5 + f8) / FG3 ≤ 5.

22.

6. The zoom lens according to claim 1, characterized in that, The radius of curvature R12 of the image side surface of the sixth lens and the radius of curvature R16 of the image side surface of the eighth lens satisfy the following condition: 0.23≤(R12+R16) / R16≤1.

12.

7. The zoom lens according to claim 1, characterized in that, When the zoom lens is at the wide-angle end, the air gap T12 between the first lens and the second lens on the optical axis, and the air gap T34 between the third lens and the fourth lens on the optical axis and the air gap T23 between the second lens and the third lens on the optical axis, satisfy the following condition: 4.65≤(T12+T34) / T23≤6.

24.

8. The zoom lens according to claim 1, characterized in that, The change in air gap ΔD1 between the first and second lenses on the optical axis when the zoom lens switches from the wide-angle end to the telephoto end and the change in air gap ΔD2 between the third and fourth lenses on the optical axis when the zoom lens switches from the wide-angle end to the telephoto end satisfy the following condition: 4.14≤|ΔD2 / ΔD1|≤5.

08.

9. The zoom lens according to claim 1, characterized in that, The air gap T67 between the sixth and seventh lenses on the optical axis, the air gap T56 between the fifth and sixth lenses on the optical axis, and the center thickness CT5 of the fifth lens satisfy the following condition: 0.88≤T67 / (T56+CT5)≤2.

07.

10. The zoom lens according to claim 1, characterized in that, When the zoom lens is at the telephoto end, the distance TDt between the object side of the first lens and the image side of the eighth lens on the optical axis and the air gap T67 between the sixth lens and the seventh lens on the optical axis satisfy the following: 2.94≤TDt / T67≤4.

77.

11. The zoom lens according to claim 1, characterized in that, The air gaps T67 between the sixth and seventh lenses on the optical axis, T78 between the seventh and eighth lenses on the optical axis, T45 between the fourth and fifth lenses on the optical axis, and T56 between the fifth and sixth lenses on the optical axis satisfy the following condition: 2.26≤(T67+T78) / (T45+T56)≤4.

69.

12. The zoom lens according to claim 1, characterized in that, The effective focal length f1 of the first lens and the effective focal length f8 of the eighth lens satisfy the following condition: 1.05 ≤ f1 / f8 ≤ 1.

23.

13. The zoom lens according to claim 1, characterized in that, The change in effective focal length Δf when the zoom lens is at the telephoto end and the wide-angle end, and the change in air gap ΔD2 of the third lens and the fourth lens on the optical axis when the zoom lens switches from the wide-angle end to the telephoto end, satisfy the following condition: 2.44≤Δf / ΔD2≤2.

69.

14. The zoom lens according to claim 1, characterized in that, The center thickness CT1 of the first lens and the edge thickness ET1 at the maximum effective radius of the first lens satisfy the following condition: 2.30≤CT1 / ET1≤3.

50.

15. The zoom lens according to claim 1, characterized in that, The distance SAG32 between the intersection of the image side of the third lens on the optical axis and the effective half-aperture of the image side of the third lens, and the distance SAG21 between the intersection of the object side of the second lens on the optical axis and the effective half-aperture of the object side of the second lens, satisfy the following condition: -2.53≤SAG32 / SAG21≤-2.

12.

16. The zoom lens according to claim 1, characterized in that, The effective focal length f1 of the first lens, the radius of curvature R1 of the object side of the first lens, and the radius of curvature R2 of the image side of the first lens satisfy the following condition: -1.35≤f1 / (R1+R2)≤-1.

07.

17. The zoom lens according to claim 1, characterized in that, The effective half-aperture DT52 of the image side of the fifth lens and the effective half-aperture DT61 of the object side of the sixth lens satisfy the following condition: 1.36≤DT52 / DT61≤1.

50.

18. The zoom lens according to claim 1, characterized in that, When the zoom lens is at the middle end, the air gap Dm2 between the third lens and the fourth lens on the optical axis and the center thickness CT3 of the third lens satisfy the following condition: 4.21≤Dm2 / CT3≤7.

08.

19. The zoom lens according to claim 1, characterized in that, The effective focal length fm of the zoom lens when it is in the middle position, the air gap Dm1 between the first lens and the second lens on the optical axis when the zoom lens is in the middle position, and the air gap Dm2 between the third lens and the fourth lens on the optical axis when the zoom lens is in the middle position satisfy the following condition: 3.90≤fm / (Dm1+Dm2)≤5.

47.

20. The zoom lens according to claim 1, characterized in that, The fifth lens is a glass lens, and the refractive index of the eighth lens is greater than 1.65 and less than or equal to 1.

69.

21. A zoom lens, characterized in that, From the object side to the image side, the following are included in sequence: The first lens group includes a first lens with positive optical power, and the total number of lenses with optical power in the first lens group is 1. A second lens group with negative optical power, the second lens group including a second lens with negative optical power and a third lens with negative optical power, the total number of lenses with optical power in the second lens group is 2; A third lens group with positive optical power, the third lens group including a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with negative optical power, a seventh lens with negative optical power, and an eighth lens with positive optical power, the total number of lenses with optical power in the third lens group is 5. The zoom lens has a total of 3 lens groups with optical power; the first lens has a convex object-side surface and a convex image-side surface; the second lens has a concave object-side surface and a concave image-side surface; the third lens has a convex object-side surface and a concave image-side surface; the fourth lens has a convex object-side surface and a concave image-side surface; the fifth lens has a convex object-side surface and a convex image-side surface; the sixth lens has a concave object-side surface; the seventh lens has a convex object-side surface and a concave image-side surface; and the eighth lens has a convex object-side surface. The second lens group and the third lens group are movably arranged on the optical axis. By adjusting the positions of the second lens group and the third lens group on the optical axis, continuous zoom of the zoom lens can be achieved. The effective focal length fw of the zoom lens at the wide-angle end and half of the maximum field of view (Semi-FOV) of the zoom lens at the wide-angle end satisfy the following condition: 31.86≤fw / tan(Semi-FOV)≤63.85; When the zoom lens is at the wide-angle end, the distance TTL from the object side of the first lens to the imaging plane on the optical axis satisfies the following condition with respect to the effective focal length variable Δf when the zoom lens is at the telephoto end and the wide-angle end: 2.07≤TTL / Δf<2.6; The change in air gap ΔD1 between the first and second lenses on the optical axis when the zoom lens switches from the wide-angle end to the telephoto end and the change in air gap ΔD2 between the third and fourth lenses on the optical axis when the zoom lens switches from the wide-angle end to the telephoto end satisfy the following condition: 4.14≤|ΔD2 / ΔD1|≤5.

08.

22. The zoom lens according to claim 21, characterized in that, The effective focal length FG2 of the second lens group and the effective focal length FG3 of the third lens group satisfy the following condition: -1.54≤FG3 / FG2≤-1.

31.

23. The zoom lens according to claim 21, characterized in that, The effective focal length ft of the zoom lens at the telephoto end satisfies the following relationship with the effective focal length f1 of the first lens: 1.77≤ft / f1≤2.

03.

24. The zoom lens according to claim 21, characterized in that, When the zoom lens is at the telephoto end, the distance TTL from the object side of the first lens to the imaging surface on the optical axis satisfies the following condition with respect to the effective focal length ft of the zoom lens at the telephoto end: 1.03≤TTL / ft≤1.

13.

25. The zoom lens according to claim 21, characterized in that, The radius of curvature R4 of the image side of the second lens and the radius of curvature R5 of the object side of the third lens satisfy the following condition: -7.16≤(R4+R5) / (R4-R5)≤-6.

94.

26. The zoom lens according to claim 21, characterized in that, The radius of curvature R7 of the object side of the fourth lens, the radius of curvature R8 of the image side of the fourth lens, and the effective focal length f4 of the fourth lens satisfy the following condition: 1.09≤(R7+R8) / f4≤1.

34.

27. The zoom lens according to claim 21, characterized in that, The effective focal lengths of the third lens group (FG3), the fourth lens (f4), the fifth lens (f5), and the eighth lens (f8) satisfy the following condition: 4.53 ≤ (f4 + f5 + f8) / FG3 ≤ 5.

22.

28. The zoom lens according to claim 21, characterized in that, The radius of curvature R12 of the image side surface of the sixth lens and the radius of curvature R16 of the image side surface of the eighth lens satisfy the following condition: 0.23≤(R12+R16) / R16≤1.

12.

29. The zoom lens according to claim 21, characterized in that, When the zoom lens is at the wide-angle end, the air gap T12 between the first lens and the second lens on the optical axis, and the air gap T34 between the third lens and the fourth lens on the optical axis and the air gap T23 between the second lens and the third lens on the optical axis, satisfy the following condition: 4.65≤(T12+T34) / T23≤6.

24.

30. The zoom lens according to claim 21, characterized in that, The air gap T67 between the sixth and seventh lenses on the optical axis, the air gap T56 between the fifth and sixth lenses on the optical axis, and the center thickness CT5 of the fifth lens satisfy the following condition: 0.88≤T67 / (T56+CT5)≤2.

07.

31. The zoom lens according to claim 21, characterized in that, When the zoom lens is at the telephoto end, the distance TDt between the object side of the first lens and the image side of the eighth lens on the optical axis and the air gap T67 between the sixth lens and the seventh lens on the optical axis satisfy the following: 2.94≤TDt / T67≤4.

77.

32. The zoom lens according to claim 21, characterized in that, The air gaps T67 between the sixth and seventh lenses on the optical axis, T78 between the seventh and eighth lenses on the optical axis, T45 between the fourth and fifth lenses on the optical axis, and T56 between the fifth and sixth lenses on the optical axis satisfy the following condition: 2.26 ≤ (T67 + T78) / (T45 + T56) ≤ 4.

69.

33. The zoom lens according to claim 21, characterized in that, The effective focal length f1 of the first lens and the effective focal length f8 of the eighth lens satisfy the following condition: 1.05 ≤ f1 / f8 ≤ 1.

23.

34. The zoom lens according to claim 21, characterized in that, The change in effective focal length Δf when the zoom lens is at the telephoto end and the wide-angle end, and the change in air gap ΔD2 of the third lens and the fourth lens on the optical axis when the zoom lens switches from the wide-angle end to the telephoto end, satisfy the following condition: 2.44≤Δf / ΔD2≤2.

69.

35. The zoom lens according to claim 21, characterized in that, The center thickness CT1 of the first lens and the edge thickness ET1 at the maximum effective radius of the first lens satisfy the following condition: 2.30≤CT1 / ET1≤3.

50.

36. The zoom lens according to claim 21, characterized in that, The distance SAG32 between the intersection of the image side surface of the third lens and the effective half-aperture of the image side surface of the third lens on the optical axis and the distance SAG21 between the intersection of the object side surface of the second lens and the effective half-aperture of the object side surface of the second lens on the optical axis satisfy the following condition: -2.53≤SAG32 / SAG21≤≤-2.

12.

37. The zoom lens according to claim 21, characterized in that, The effective focal length f1 of the first lens, the radius of curvature R1 of the object side of the first lens, and the radius of curvature R2 of the image side of the first lens satisfy the following condition: -1.35≤f1 / (R1+R2)≤-1.

07.

38. The zoom lens according to claim 21, characterized in that, The effective half-aperture DT52 of the image side of the fifth lens and the effective half-aperture DT61 of the object side of the sixth lens satisfy the following condition: 1.36≤DT52 / DT61≤1.

50.

39. The zoom lens according to claim 21, characterized in that, When the zoom lens is at the middle end, the air gap Dm2 between the third lens and the fourth lens on the optical axis and the center thickness CT3 of the third lens satisfy the following condition: 4.21≤Dm2 / CT3≤7.

08.

40. The zoom lens according to claim 21, characterized in that, The effective focal length fm of the zoom lens when it is in the middle position, the air gap Dm1 between the first lens and the second lens on the optical axis when the zoom lens is in the middle position, and the air gap Dm2 between the third lens and the fourth lens on the optical axis when the zoom lens is in the middle position satisfy the following condition: 3.90≤fm / (Dm1+Dm2)≤5.

47.

41. The zoom lens according to claim 21, characterized in that, The fifth lens is a glass lens, and the refractive index of the eighth lens is greater than 1.65 and less than or equal to 1.69.

Images