Zoom lens

Abstract

The present application relates to the field of optical lens, provide a kind of zoom lens, the zoom lens is sequentially by the first lens with negative refractive power, the second lens group with positive refractive power, the fifth lens with positive refractive power and the sixth lens with negative refractive power from object side to image side, in zooming, the first lens, the second lens group, the fifth lens and the sixth lens, the interval of adjacent lens or lens group in the direction of optical axis changes, the second lens group is composed of the second lens with positive refractive power, the third lens with negative refractive power and the fourth lens with negative refractive power, and satisfy the following relationship: 1.80≤f_Tele / f_Wide≤2.044;40.00≤D12_Wide / D12_Tele≤48.00;2.00≤d11_Wide / d11_Tele≤2.60.The present application becomes small in contraction, FNO is bright in photography, and has good optical characteristics.

Description

Technical Field

[0001] This invention relates to a zoom lens with a retractable structure. More particularly, it relates to a zoom lens suitable for use with a high-resolution CCD. Smartphone camera components with CMOS and other imaging elements Digital cameras and similar devices have zoom lenses that are bright and have good optical characteristics when the F-number (hereinafter referred to as FNO) at the wide-angle end is 2.0 or less, have a zoom ratio of 1.80 or more, and are compact when the TTL (total optical length of the zoom lens) at the zoom point is 8.00mm or less, and consist of six elements in four groups. Background Technology

[0002] In recent years, there has been a search for a zoom lens with an FNO of ≤2.0 at the wide-angle end, a zoom ratio of ≥1.80, good optical characteristics, and the ability to shorten the TTL by retracting the lens barrel into the camera when not in use, and to become smaller when retracted.

[0003] The development of a zoom lens consisting of six lenses is underway. As a zoom lens with this six-element structure, Patent Document 1 proposes a lens consisting of three groups of six lenses.

[0004] The camera lens disclosed in the embodiment of Patent Document 1 has a zoom ratio of 4.74 or higher, but when the FNO at the wide-angle end is 2.552 or higher, the brightness is insufficient, the TTL during photography is also relatively long, and miniaturization is not sufficient.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: US Patent Publication No. US2020 / 0241265A1 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] The purpose of this invention is to provide a zoom lens that becomes compact when the TTL is ≤ 8.00mm when retracted, becomes bright when the FNO at the wide-angle end is ≤ 2.0 during photography, has good optical characteristics, a zoom ratio ≥ 1.80, and is composed of four groups of six lenses.

[0010] Methods for solving problems

[0011] In order to achieve the above objectives, the inventors of this invention carefully studied the ratio of the on-axis distance from the image side of the first lens to the object side of the second lens at the wide-angle end to the on-axis distance from the image side of the first lens to the object side of the second lens at the telephoto end, and the ratio of the on-axis distance from the image side of the fifth lens to the object side of the sixth lens at the wide-angle end to the on-axis distance from the image side of the fifth lens to the object side of the sixth lens at the telephoto end. As a result, they found that a zoom lens that improves the problems of the prior art could be obtained, and thus the present invention was conceived.

[0012] An embodiment of the present invention provides a zoom lens, which, from the object side to the image side, is composed of a first lens with negative refractive power, a second lens group with positive refractive power, a fifth lens with positive refractive power, and a sixth lens with negative refractive power.

[0013] During zooming, the spacing between adjacent lenses or lens groups along the optical axis changes among the first lens, the second lens group, the fifth lens, and the sixth lens.

[0014] The second lens group consists of a second lens with positive refractive power, a third lens with negative refractive power, and a fourth lens with negative refractive power.

[0015] The zoom lens satisfies the following relationships (1) to (3):

[0016] 1.80≤f_Tele / f_Wide≤2.044(1)

[0017] 40.00≤D12_Wide / D12_Tele≤48.00(2)

[0018] 2.00≤d11_Wide / d11_Tele≤2.60(3)

[0019] in,

[0020] f_Wide: The overall focal length of the zoom lens at the wide-angle end;

[0021] f_Tele: The overall focal length of the zoom lens at the telephoto end;

[0022] D12_Wide: The on-axis distance from the image side of the first lens to the object side of the second lens at the wide-angle end;

[0023] D12_Tele: The on-axis distance from the image side of the first lens at the telephoto end to the object side of the second lens;

[0024] d11_Wide: The axial distance from the image-side surface of the fifth lens to the object-side surface of the sixth lens at the wide-angle end;

[0025] d11_Tele: The on-axis distance from the image side of the fifth lens at the telephoto end to the object side of the sixth lens.

[0026] Preferably, the following relationship (4) is satisfied:

[0027] 0.30≤d9_Wide / d9_Tele≤0.36(4)

[0028] in,

[0029] d9_Wide: The axial distance from the image side of the fourth lens to the object side of the fifth lens at the wide-angle end;

[0030] d9_Tele: The on-axis distance from the image side of the fourth lens at the telephoto end to the object side of the fifth lens.

[0031] Preferably, the following relationship (5) is satisfied:

[0032] -1.30≤f1 / fG2≤-1.00(5)

[0033] in,

[0034] f1: Focal length of the first lens;

[0035] fG2: Combined focal length of the second lens group.

[0036] Preferably, the following relation (6) is satisfied:

[0037] -1.75≤f3 / f2≤-1.35(6)

[0038] in,

[0039] f2: Focal length of the second lens;

[0040] f3: Focal length of the third lens.

[0041] Preferably, the following relation (7) is satisfied:

[0042] -1.75≤f4 / f2≤-1.35(7)

[0043] in,

[0044] f2: Focal length of the second lens;

[0045] f4: Focal length of the fourth lens.

[0046] Preferably, the following relation (8) is satisfied:

[0047] 0.30≤f5 / fG2≤0.40(8)

[0048] in,

[0049] f5: Focal length of the fifth lens;

[0050] fG2: Combined focal length of the second lens group.

[0051] Preferably, the following relation (9) is satisfied:

[0052] -1.50≤f6 / fG2≤-1.00(9)

[0053] in,

[0054] f6: Focal length of the sixth lens;

[0055] fG2: Combined focal length of the second lens group.

[0056] Preferably, the first lens is made of glass.

[0057] Invention Effects

[0058] The beneficial effects of the present invention are as follows.

[0059] According to the present invention, in particular, there is an invention relating to a zoom lens suitable for using a high-resolution CCD. Smartphone camera components with CMOS and other imaging elements Digital cameras, etc., become smaller when the TTL is ≤ 8.00mm, become bright when the FNO at the wide-angle end is ≤ 2.0, have good optical characteristics, a zoom ratio ≥ 1.80, and are zoom lenses composed of four groups of six elements. Attached Figure Description

[0060] Figure 1 This is a diagram showing a schematic structure of the zoom lens LA according to Embodiment 1 of the present invention.

[0061] Figure 2 This is a diagram showing the axial spherical aberration, astigmatism, and distortion at the wide-angle end of the zoom lens LA of Embodiment 1 of the present invention.

[0062] Figure 3 This is a diagram showing the axial spherical aberration, astigmatism, and distortion at the telephoto end of the zoom lens LA according to Embodiment 1 of the present invention.

[0063] Figure 4 This is a diagram showing a schematic structure of the zoom lens LA according to Embodiment 2 of the present invention.

[0064] Figure 5 This is a diagram showing the axial spherical aberration, astigmatism, and distortion at the wide-angle end of the zoom lens LA of Embodiment 2 of the present invention.

[0065] Figure 6This is a diagram showing the axial spherical aberration, astigmatism, and distortion at the telephoto end of the zoom lens LA of Embodiment 2 of the present invention.

[0066] Figure 7 This is a diagram showing a schematic structure of the zoom lens LA according to Embodiment 3 of the present invention.

[0067] Figure 8 This is a diagram showing the axial spherical aberration, astigmatism, and distortion at the wide-angle end of the zoom lens LA of Embodiment 3 of the present invention.

[0068] Figure 9 This is a diagram showing the axial spherical aberration, astigmatism, and distortion at the telephoto end of the zoom lens LA of Embodiment 3 of the present invention.

[0069] Figure 10 This is a diagram showing a schematic structure of the zoom lens LA according to Embodiment 4 of the present invention.

[0070] Figure 11 This is a diagram showing the axial spherical aberration, astigmatism, and distortion at the wide-angle end of the zoom lens LA of Embodiment 4 of the present invention.

[0071] Figure 12 This is a diagram showing the axial spherical aberration, astigmatism, and distortion at the telephoto end of the zoom lens LA of Embodiment 4 of the present invention.

[0072] Figure 13 This is a diagram showing a schematic structure of the zoom lens LA according to Embodiment 5 of the present invention.

[0073] Figure 14 This is a diagram showing the axial spherical aberration, astigmatism, and distortion at the wide-angle end of the zoom lens LA of Embodiment 5 of the present invention.

[0074] Figure 15 This is a diagram showing the axial spherical aberration, astigmatism, and distortion at the telephoto end of the zoom lens LA of Embodiment 5 of the present invention. Detailed Implementation

[0075] The present invention will be further described below with reference to the accompanying drawings and embodiments. To make the objectives, technical solutions, and advantages of the present invention clearer, the various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of the present invention to facilitate a better understanding of the invention. However, the technical solutions claimed in the present invention can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0076] An embodiment of the zoom lens of the present invention will be described. This zoom lens LA has a lens system with a four-group, six-element structure. In this lens system, from the object side to the image side, a first lens L1, a second lens group G2, a fifth lens L5, and a sixth lens L6 are arranged. The second lens group G2 is composed of a second lens L2, a third lens L3, and a fourth lens L4. A glass plate GF is disposed between the sixth lens L6 and the image plane. This glass plate GF can be assumed to include a glass cover and various filters. In the present invention, the glass plate GF can be positioned in different locations, or this structure can be omitted.

[0077] The first lens L1 is a lens with negative refractive power, the second lens group G2 is a lens group with positive refractive power, the fifth lens L5 is a lens with positive refractive power, and the sixth lens L6 is a lens with negative refractive power. The second lens group G2 is composed of the second lens L2, the third lens L3, and the fourth lens L4. To effectively correct various aberrations, it is desirable to make all surfaces of these six lenses aspherical.

[0078] The zoom lens LA satisfies the following relationship (1):

[0079] 1.80≤f_Tele / f_Wide≤2.044(1)

[0080] Equation (1) specifies the zoom ratio of the zoom lens LA. When equation (1) is satisfied, it is easy to correct various aberrations and the zoom ratio becomes sufficient, so it is preferred.

[0081] The zoom lens LA satisfies the following relationship (2):

[0082] 40.00≤D12_Wide / D12_Tele≤48.00(2)

[0083] Equation (2) specifies the ratio of the axial distance D12_Wide between the image-side surface S2 of the first lens L1 and the object-side surface S3 of the second lens L2 at the wide-angle end to the axial distance D12_Tele between the image-side surface S2 of the first lens L1 and the object-side surface S3 of the second lens L2 at the telephoto end. Within the range of Equation (2), it is easy to achieve miniaturization during zoom reduction and correction of various aberrations at the wide-angle end with FNO≤2.0 and zoom ratio≥1.80, and is therefore preferred.

[0084] The zoom lens LA satisfies the following relationship (3):

[0085] 2.00≤d11_Wide / d11_Tele≤2.60(3)

[0086] Equation (3) specifies the ratio of the on-axis distance d11_Wide from the image-side surface S10 of the fifth lens L5 to the object-side surface S11 of the sixth lens L6 at the wide-angle end to the on-axis distance d11_Tele from the image-side surface S10 of the fifth lens L5 to the object-side surface S11 of the sixth lens L6 at the telephoto end. Within the range of equation (3), it is easy to achieve miniaturization during zoom reduction and correction of various aberrations at the wide-angle end with FNO≤2.0 and zoom ratio≥1.80, and is therefore preferred.

[0087] The zoom lens LA satisfies the following relationship (4):

[0088] 0.30≤d9_Wide / d9_Tele≤0.36(4)

[0089] Equation (4) specifies the ratio of the on-axis distance d9_Wide from the image-side surface S8 of the fourth lens L4 to the object-side surface S9 of the fifth lens L5 at the wide-angle end to the on-axis distance d9_Tele from the image-side surface S8 of the fourth lens L4 to the object-side surface S9 of the fifth lens L5 at the telephoto end. Within the range of Equation (4), it is easy to achieve miniaturization during zoom reduction and correction of various aberrations at the wide-angle end with FNO≤2.0 and zoom ratio≥1.80, and is therefore preferred.

[0090] The zoom lens LA satisfies the following relationship (5):

[0091] -1.30≤f1 / fG2≤-1.00(5)

[0092] Equation (5) specifies the ratio of the focal length f1 of the first lens L1 to the combined focal length fG2 of the second lens group G2. Within the range of equation (5), it is easy to achieve miniaturization during zooming and correction of various aberrations at the wide-angle end with FNO≤2.0 and zoom ratio≥1.80, and is therefore preferred.

[0093] The zoom lens LA satisfies the following relationship (6):

[0094] -1.75≤f3 / f2≤-1.35(6)

[0095] Equation (6) specifies the ratio of the focal length f3 of the third lens L3 to the focal length f2 of the second lens L2. Within the range of equation (6), it is easy to achieve miniaturization during zooming and correction of various aberrations at the wide-angle end with FNO≤2.0 and zoom ratio≥1.80, and is therefore preferred.

[0096] The zoom lens LA satisfies the following relationship (7):

[0097] -1.75≤f4 / f2≤-1.35(7)

[0098] Equation (7) specifies the ratio of the focal length f4 of the fourth lens L4 to the focal length f2 of the second lens L2. Within the range of equation (7), it is easy to achieve miniaturization during zooming and correction of various aberrations at the wide-angle end with FNO≤2.0 and zoom ratio≥1.80, and is therefore preferred.

[0099] The zoom lens LA satisfies the following relationship (8):

[0100] 0.30≤f5 / fG2≤0.40(8)

[0101] Equation (8) specifies the ratio of the focal length f5 of the fifth lens L5 to the combined focal length fG2 of the second lens group G2. Within the range of equation (8), it is easy to achieve miniaturization during zooming and correction of various aberrations at the wide-angle end with FNO≤2.0 and zoom ratio≥1.80, and is therefore preferred.

[0102] The zoom lens LA satisfies the following relationship (9):

[0103] -1.50≤f6 / fG2≤-1.00(9)

[0104] Equation (9) specifies the ratio of the focal length f6 of the sixth lens L6 to the combined focal length fG2 of the second lens group G2. Within the range of equation (9), it is easy to achieve miniaturization during zooming and correction of various aberrations at the wide-angle end with FNO≤2.0 and zoom ratio≥1.80, and is therefore preferred.

[0105] By satisfying the above structure and relationship in the four groups of six elements constituting the zoom lens LA, a zoom lens can be obtained that is small when the TTL is ≤ 8.00mm, bright when the FNO is ≤ 2.0 at the wide-angle end during photography, has good optical characteristics, a zoom ratio ≥ 1.80, and is composed of four groups of six elements.

[0106] (Example)

[0107] The zoom lens LA of the present invention will be described below using examples. The symbols used in each example are shown below. It should be noted that the units for distance, radius, and on-axis thickness are all millimeters (mm).

[0108] f: Overall focal length of the zoom lens LA

[0109] f1: Focal length of the first lens L1

[0110] fG2: Combined focal length of the second lens group G2

[0111] f2: Focal length of the second lens L2

[0112] f3: Focal length of the third lens L3

[0113] f4: Focal length of the fourth lens L4

[0114] f5: Focal length of the fifth lens L5

[0115] f6: Focal length of the sixth lens L6

[0116] FNO: Aperture value (the ratio of the effective focal length to the entrance pupil diameter of a zoom lens), F-number

[0117] 2ω: Full View

[0118] STOP: Aperture

[0119] R: Radius of curvature of the optical surface; for lenses, it is the central radius of curvature.

[0120] R1: Radius of curvature of the object surface S1 of the first lens L1

[0121] R2: Radius of curvature of the image-side surface S2 of the first lens L1.

[0122] R3: Radius of curvature of the object surface S3 of the second lens L2

[0123] R4: Radius of curvature of the image-side surface S4 of the second lens L2.

[0124] R5: Radius of curvature of the object surface S5 of the third lens L3.

[0125] R6: Radius of curvature of the image-side surface S6 of the third lens L3.

[0126] R7: Radius of curvature of the object surface S7 of the fourth lens L4

[0127] R8: Radius of curvature of the image-side surface S8 of the fourth lens L4.

[0128] R9: Radius of curvature of the object surface S9 of the fifth lens L5.

[0129] R10: Radius of curvature of the image-side surface S10 of the fifth lens L5.

[0130] R11: Radius of curvature of the object surface S11 of the sixth lens L6

[0131] R12: Radius of curvature of the image-side surface S12 of the sixth lens L6.

[0132] R13: Radius of curvature of the surface S13 of the glass plate GF.

[0133] R14: Radius of curvature of the image-side surface S14 of the glass plate GF.

[0134] d: Axial thickness of the lens, or axial distance between lenses

[0135] d1: On-axis thickness of the first lens L1

[0136] D12: The axial distance from the image-side surface S2 of the first lens L1 to the object-side surface S3 of the second lens L2.

[0137] d2: The axial distance from the image-side surface S2 of the first lens L1 to the aperture STOP.

[0138] d3: The axial distance from the aperture stop to the object-side surface S3 of the second lens L2.

[0139] d4: On-axis thickness of the second lens L2

[0140] d5: The axial distance from the image-side surface S4 of the second lens L2 to the object-side surface S5 of the third lens L3.

[0141] d6: On-axis thickness of the third lens L3

[0142] d7: The axial distance from the image-side surface S6 of the third lens L3 to the object-side surface S7 of the fourth lens L4.

[0143] d8: On-axis thickness of the fourth lens L4

[0144] d9: The axial distance from the image-side surface S8 of the fourth lens L4 to the object-side surface S9 of the fifth lens L5.

[0145] d10: On-axis thickness of the fifth lens L5

[0146] d11: The axial distance from the image-side surface S10 of the fifth lens L5 to the object-side surface S11 of the sixth lens L6.

[0147] d12: On-axis thickness of the sixth lens L6

[0148] d13: The axial distance from the image-side surface S12 of the sixth lens L6 to the object-side surface S13 of the glass plate GF.

[0149] d14: Axial thickness of the glass plate GF

[0150] d15: The axial distance from the image-side surface S14 of the glass plate GF to the image plane.

[0151] nd: Refractive index of the d-line

[0152] nd1: Refractive index of the d-line of the first lens L1

[0153] nd2: Refractive index of the d-line of the second lens L2

[0154] nd3: Refractive index of the d-line of the third lens L3

[0155] nd4: Refractive index of the d-line of the fourth lens L4

[0156] nd5: Refractive index of the d-line of the fifth lens L5

[0157] nd6: Refractive index of the d-line of the sixth lens L6

[0158] ndg: The refractive index of the d-line of the glass plate GF

[0159] νd: Abbe number

[0160] ν1: Abbe number of the first lens L1

[0161] ν2: Abbe number of the second lens L2

[0162] ν3: Abbe number of the third lens L3

[0163] ν4: Abbe number of the fourth lens L4

[0164] ν5: Abbe number of the fifth lens L5

[0165] ν6: Abbe number of the sixth lens L6

[0166] νg: Abbe number of the glass plate GF

[0167] TTL: Total optical length of a zoom lens (the axial distance from the object surface S1 of the first lens L1 to the image plane).

[0168] LB: The axial distance from the image-side surface S12 of the sixth lens L6 to the image plane.

[0169] IH: Like high

[0170] (Example 1)

[0171] Figure 1 This is a structural diagram showing the configuration of the zoom lens LA of Embodiment 1. Table 1 shows the radius of curvature R, lens axial thickness or inter-lens axial distance d, refractive index nd, and Abbe number νd of each object-side and image-side surface of the first lens L1 to the sixth lens L6 constituting the zoom lens LA of Embodiment 1. Table 2 shows the values ​​of A to D during photography and during zoom reduction. Table 3 shows the conic coefficient k and aspherical coefficient. Table 4 shows FNO, 2ω, f, TTL, LB, f1, fG2, f2, f3, f4, f5, f6, IH, and zoom ratio.

[0172] Table 1

[0173]

[0174] Reference wavelength = 587.6nm

[0175] Table 2

[0176]

[0177] Table 3

[0178]

[0179] Where k is the conic coefficient, and A4, A6, A8, A10, A12, A14, and A16 are the aspheric coefficients.

[0180] y=(x 2 / R) / [1+{1-(k+1)(x 2 / R 2 )} 1 / 2 ]+A4x 4 +A6x 6 +A8x 8 +A10x 10 +A12x 12 +A14x 14 +A16x 16 (10)

[0181] Where x is the perpendicular distance between a point on the aspherical curve and the optical axis, and y is the aspherical depth (the perpendicular distance between a point on the aspherical surface at a distance x from the optical axis and a tangent plane at the vertex of the aspherical optical axis).

[0182] For convenience, the aspherical surfaces of each lens surface are as shown in formula (10), but are not particularly limited to the aspherical polynomial form of formula (10).

[0183] Table 4

[0184]

[0185]

[0186]

[0187] Table 21, which appears later, shows the values ​​of the parameters in each of Examples 1 to 5 that correspond to the parameters specified in relations (1) to (9).

[0188] As shown in Table 21, Example 1 satisfies the relations (1) to (9).

[0189] Figure 2 The diagram shows the axial spherical aberration, astigmatism, and distortion at the wide-angle end of the zoom lens LA of Example 1. Figure 3The figure shows the axial spherical aberration, astigmatism, field curvature, and distortion at the telephoto end. It should be noted that the field curvature S in the figure is relative to the sagittal image plane, and T is relative to the tangential image plane; this is also the case in Examples 2-5. It can be seen that the zoom lens LA of Example 1 becomes smaller when the TTL = 7.870 at the zoom level, becomes brighter when the FNO = 1.96 at the wide-angle end, and has a zoom ratio of 2.044, and as... Figure 2 , Figure 3 As shown, it has excellent optical properties.

[0190] (Example 2)

[0191] Figure 4 This is a structural diagram showing the configuration of the zoom lens LA of Embodiment 2. Table 5 shows the radius of curvature R, lens axial thickness or inter-lens axial distance d, refractive index nd, and Abbe number νd of each object-side and image-side surface of the first lens L1 to the sixth lens L6 constituting the zoom lens LA of Embodiment 2. Table 6 shows the values ​​of A to D during photography and during zoom reduction. Table 7 shows the conic coefficient k and aspherical coefficient. Table 8 shows FNO, 2ω, f, TTL, LB, f1, fG2, f2, f3, f4, f5, f6, IH, and zoom ratio.

[0192] Table 5

[0193]

[0194] Reference wavelength = 587.6nm

[0195] Table 6

[0196]

[0197] Table 7

[0198]

[0199] Table 8

[0200]

[0201]

[0202]

[0203] As shown in Table 21, Example 2 satisfies the relations (1) to (9).

[0204] Figure 5 The diagram shows the axial spherical aberration, astigmatism, and distortion at the wide-angle end of the zoom lens LA in Example 2. Figure 6The diagram shows the axial spherical aberration, astigmatism, and distortion at the telephoto end. It can be seen that the zoom lens LA of Example 2 becomes smaller when the TTL = 7.925 at the zoom level, becomes brighter when the FNO = 1.96 at the wide-angle end, and has a zoom ratio of 2.000. Figure 5 , Figure 6 As shown, it has excellent optical properties.

[0205] (Example 3)

[0206] Figure 7 This is a structural diagram showing the configuration of the zoom lens LA of Embodiment 3. Table 9 shows the radius of curvature R, lens axial thickness or inter-lens axial distance d, refractive index nd, and Abbe number νd of each object-side and image-side surface of the first lens L1 to the sixth lens L6 constituting the zoom lens LA of Embodiment 3. Table 10 shows the values ​​of A to D during photography and during zoom reduction. Table 11 shows the conic coefficient k and aspherical coefficient. Table 12 shows FNO, 2ω, f, TTL, LB, f1, fG2, f2, f3, f4, f5, f6, IH, and zoom ratio.

[0207] Table 9

[0208]

[0209] Reference wavelength = 587.6nm

[0210] Table 10

[0211]

[0212] Table 11

[0213]

[0214] Table 12

[0215]

[0216]

[0217]

[0218] As shown in Table 21, Example 3 satisfies the relations (1) to (9).

[0219] Figure 8 The diagram shows the axial spherical aberration, astigmatism, and distortion at the wide-angle end of the zoom lens LA in Example 3. Figure 9The diagram shows the axial spherical aberration, astigmatism, and distortion at the telephoto end. It can be seen that the zoom lens LA of Example 3 becomes smaller when the TTL = 7.902 at the zoom level, becomes brighter when the FNO = 1.97 at the wide-angle end, and has a zoom ratio of 2.000. Figure 8 , Figure 9 As shown, it has excellent optical properties.

[0220] (Example 4)

[0221] Figure 10 This is a structural diagram showing the configuration of the zoom lens LA of Embodiment 4. Table 13 shows the radius of curvature R, lens axial thickness or inter-lens axial distance d, refractive index nd, and Abbe number νd of each object-side and image-side surface of the first lens L1 to the sixth lens L6 constituting the zoom lens LA of Embodiment 4. Table 14 shows the values ​​of A to D during photography and during zoom reduction. Table 15 shows the conic coefficient k and aspherical coefficient. Table 16 shows FNO, 2ω, f, TTL, LB, f1, fG2, f2, f3, f4, f5, f6, IH, and zoom ratio.

[0222] Table 13

[0223]

[0224] Reference wavelength = 587.6nm

[0225] Table 14

[0226]

[0227] Table 15

[0228]

[0229] Table 16

[0230]

[0231]

[0232]

[0233] As shown in Table 21, Example 4 satisfies the relations (1) to (9).

[0234] Figure 11 The diagram shows the axial spherical aberration, astigmatism, and distortion at the wide-angle end of the zoom lens LA in Example 4. Figure 12The diagram shows the axial spherical aberration, astigmatism, and distortion at the telephoto end. It can be seen that the zoom lens LA of Example 4 becomes smaller when the TTL = 7.898 at the zoom level, becomes brighter when the FNO = 1.96 at the wide-angle end, and has a zoom ratio of 2.000. Figure 11 , Figure 12 As shown, it has excellent optical properties.

[0235] (Example 5)

[0236] Figure 13 This is a structural diagram showing the configuration of the zoom lens LA of Embodiment 5. Table 17 shows the radius of curvature R, lens axial thickness or inter-lens axial distance d, refractive index nd, and Abbe number νd of each object-side and image-side surface of the first lens L1 to the sixth lens L6 constituting the zoom lens LA of Embodiment 5. Table 18 shows the values ​​of A to D during photography and during zoom reduction. Table 19 shows the conic coefficient k and aspherical coefficient. Table 20 shows FNO, 2ω, f, TTL, LB, f1, fG2, f2, f3, f4, f5, f6, IH, and zoom ratio.

[0237] Table 17

[0238]

[0239] Reference wavelength = 587.6nm

[0240] Table 18

[0241]

[0242] Table 19

[0243]

[0244] Table 20

[0245]

[0246]

[0247]

[0248] As shown in Table 21, Example 5 satisfies the relations (1) to (9).

[0249] Figure 14 The diagram shows the axial spherical aberration, astigmatism, and distortion at the wide-angle end of the zoom lens LA in Example 5. Figure 15The diagram shows axial spherical aberration, astigmatism, and distortion at the telephoto end. It can be seen that the zoom lens LA of Example 5 becomes smaller when the TTL is 7.864 at the zoom level, becomes brighter when the FNO at the wide-angle end is 1.95, and has a zoom ratio of 2.000. Figure 14 , Figure 15 As shown, it has excellent optical properties.

[0250] Table 21 shows the values ​​of the parameters in Examples 1 to 5 that correspond to the parameters specified in relations (1) to (9).

[0251] Table 21

[0252]

[0253] Those skilled in the art will understand that the above embodiments are specific embodiments for implementing the present invention, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of the present invention.

Claims

1. A zoom lens, characterized in that, The zoom lens, from the object side to the image side, consists of a first lens with negative refractive power, a second lens group with positive refractive power, a fifth lens with positive refractive power, and a sixth lens with negative refractive power. During zooming, the spacing between adjacent lenses or lens groups along the optical axis changes among the first lens, the second lens group, the fifth lens, and the sixth lens. The second lens group consists of a second lens with positive refractive power, a third lens with negative refractive power, and a fourth lens with negative refractive power. Wherein, the overall focal length of the zoom lens at the wide-angle end is f_Wide, the overall focal length of the zoom lens at the telephoto end is f_Tele, the axial distance from the image side of the first lens to the object side of the second lens at the wide-angle end is D12_Wide, the axial distance from the image side of the first lens to the object side of the second lens at the telephoto end is D12_Tele, the axial distance from the image side of the fifth lens to the object side of the sixth lens at the wide-angle end is d11_Wide, and the axial distance from the image side of the fifth lens to the object side of the sixth lens at the telephoto end is d11_Tele, and the following relationships (1)~(3) are satisfied: 1.80≤f_Tele / f_Wide≤2.044; (1) 40.00≤D12_Wide / D12_Tele≤48.00; (2) 2.00≤d11_Wide / d11_Tele≤2.60(3).

2. The zoom lens according to claim 1, characterized by The axial distance from the image side of the fourth lens at the wide-angle end to the object side of the fifth lens is d9_Wide, and the axial distance from the image side of the fourth lens to the object side of the fifth lens at the telephoto end is d9_Tele, and satisfies the following relationship (4): 0.30≤d9_Wide / d9_Tele≤0.36(4).

3. The zoom lens according to claim 1, characterized by The focal length of the first lens is f1, and the combined focal length of the second lens group is fG2, and they satisfy the following relationship (5): -1.30≤f1 / fG2≤-1.00(5).

4. The zoom lens according to claim 1, characterized by The focal length of the second lens is f2, and the focal length of the third lens is f3, and they satisfy the following relationship (6): -1.75≤f3 / f2≤-1.35(6).

5. The zoom lens according to claim 1, characterized by The focal length of the second lens is f2, and the focal length of the fourth lens is f4, and they satisfy the following relationship (7): -1.75≤f4 / f2≤-1.35(7).

6. The zoom lens according to claim 1, characterized by The focal length of the fifth lens is f5, the combined focal length of the second lens group is fG2, and the following relationship (8) is satisfied: 0.30≤f5 / fG2≤0.40(8).

7. The zoom lens according to claim 1, characterized by The focal length of the sixth lens is f6, the combined focal length of the second lens group is fG2, and the following relationship (9) is satisfied: -1.50≤f6 / fG2≤-1.00(9).

8. The zoom lens according to claim 1, characterized by The first lens is made of glass.

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