Super wide angle zoom lens

Claim 2

A super wide angle zoom lens comprising: a front group exhibiting a negative refracting power and including, sequentially from an object, a first lens element having a negative refracting power, a second lens element having a negative refracting power and a third lens element having a positive refracting power, at least one surface of the lens element of said front group being aspherical; and a rear group having a positive refracting power, disposed closer to the image side than said front group, the rear group including a lens group disposed closest to said front group side; wherein when variable power operation is performed from the wide angle end side to the telephoto end side, at least one of said front group and said lens group disposed closest to said front group side in said rear group moves to reduce air space on the optical axis between said front group and said rear group, and wherein said front group is constructed to satisfy the following condition: (300/fw)≦|f.sub.1 |≦(680/fw) where f 1 is the focal distance of said front group, and fw is the focal distance of the whole system at the wide angle end.

Claim 3

The super wide angle zoom lens as set forth in claim 1, wherein said front group is constructed to satisfy the following condition: 0.12≦d.sub.23 /fw≦2.0 where d 23 is the axial air space between a surface, closest to the image, of said second lens element and a surface, closest to the object, of said third lens element, and fw is the focal distance of the entire system at the wide angle end.

Claim 4

The super wide angle zoom lens as set forth in claim 1, wherein said front group has a first lens group including said first, second, and third lens elements, said rear group has said lens group disposed closest to said front group side as a second lens group having a positive refracting power and has a third lens group having a negative refracting power and a fourth lens group having a positive refracting power in the order from the object side, said third lens group having the negative refracting power includes a joint negative lens element consisting of positive and negative lenses joined to each other, and said fourth lens group having the positive refracting power includes a joint positive lens element consisting of positive and negative lenses joined to each other on the closest-to-image-side.

Claim 5

The super wide angle zoom lens as set forth in claim 3, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 15.5˜27.3, 2ω = 111.2°˜76.4°, F.sub.NO = 4.1 r d ν n ______________________________________ 1 69.600 2.50 45.4 1.79668 2 20.275 15.50 3 -80.398 2.00 45.4 1.79668 4 37.112 6.00 5 46.526 5.30 35.2 1.74950 6 -815.420 (d.sub.6).sub. 7 26.848 1.60 33.9 1.80384 8 14.972 4.50 65.8 1.46450 9 97.280 0.20 10 38.990 3.00 41.4 1.57501 11 -50.400 (d.sub.11) 12 -36.378 2.30 28.3 1.72825 13 -13.883 1.50 55.6 1.69680 14 128.521 (d.sub.14) 15 24.647 3.00 54.6 1.51454 16 73.993 0.50 17 41.947 2.00 26.1 1.78470 18 24.197 3.20 19 -103.008 3.00 67.9 1.59319 20 -28.765 0.10 21 217.566 8.00 65.4 1.60300 22 -15.505 2.00 23.0 1.86074 23 -30.196 (Bf) ______________________________________ f 15.450 24.000 27.300 d6 21.412 3.704 0.398 d11 6.575 11.685 13.610 d14 7.671 2.561 0.636 Bf 38.211 47.501 51.002 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 69.600 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.79789E.sup.-05, C.sub.6 = 0.39445E.sup.-08, C.sub.8 = 0.24046E.sup.-11, C.sub.10 = 0.31560E.sup.-14 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.388, |f.sub.1 | = 24.942 |AS-S|/fw = 0.25367 (φ = 55.66) f.sub.2 /fw = 2.330, |f.sub.3 |/fw = 2.773 f.sub.4 /fw = 2.307, d.sub.23 /L = 0.192 d.sub.4p = 8.0, |n.sub.3n -n.sub.3p | = 0.03145 ν.sub.3p -ν.sub.3n = 27.3, n.sub.4n -n.sub.4p = 0.2577 ν.sub.4p -ν.sub.4n = 42.4 ______________________________________ where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; fw: the focal distance of the entire system at the wide angle end; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 1 : the focal distance of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 ]+C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 6

The super wide angle zoom lens as set forth in claim 3, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 16.4˜27.3, 2ω = 108.2°˜76.4°, F.sub.NO = 4.1 r d ν n ______________________________________ 1 56.830 2.50 45.4 1.79668 2 22.588 13.00 3 203.239 2.00 43.4 1.84042 4 29.159 14.20 5 29.712 3.50 25.5 1.80458 6 37.859 (d.sub.6).sub. 7 35.294 1.30 33.9 1.80384 8 16.316 4.00 70.4 1.48749 9 160.741 0.20 10 35.749 3.00 38.0 1.60342 11 -53.604 (d.sub.11) 12 -30.014 2.50 27.8 1.69911 13 -12.979 1.50 60.0 1.64000 14 141.313 (d.sub.14) 15 29.674 3.50 58.9 1.51823 16 -229.981 0.10 17 92.266 2.00 28.6 1.79504 18 28.825 2.50 19 -150.071 3.00 65.4 1.60300 20 -34.756 0.10 21 205.091 8.00 57.5 1.67025 22 -15.837 1.80 23.0 1.86074 23 -34.904 (Bf) ______________________________________ f 16.400 24.000 27.300 d6 18.553 4.145 0.916 d11 8.282 13.087 15.115 d14 7.722 2.917 0.888 Bf 39.789 47.798 51.178 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 56.830 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.41777E.sup.-05, C.sub.6 = 0.36563E.sup.-09, C.sub.8 = -0.98160E.sup.-12, C.sub.10 = 0.21972E.sup.-14 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.8659, |f.sub.1 | = 24.941 |AS-S|/fw = 0.1800 (φ = 55.73) f.sub.2 /fw = 2.195, |f.sub.3 |/fw = 2.612 f.sub.4 /fw = 2.174, d.sub.23 /L = 0.4034 d.sub.4p = 8.0, |n.sub.3n -n.sub.3p | = 0.05911 ν.sub.3p -ν.sub.3n = -32.2, n.sub.4n -n.sub.4p = 0.19049 ν.sub.4p -ν.sub.4n = 34.5 ______________________________________ where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; fw: the focal distance of the entire system at the wide angle end; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 1 the focal distance of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 ]+C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 7

The super wide angle zoom lens as set forth in claim 3, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 18.4˜27.3, 2ω = 101.2°˜76.4°, F.sub.NO = 4.1 r d ν n ______________________________________ 1 49.794 2.50 40.9 1.79631 2 17.702 12.00 3 -83.638 2.00 45.4 1.79668 4 47.407 10.70 5 50.613 3.00 27.8 1.69911 6 511.053 (d.sub.6).sub. 7 28.622 1.50 35.7 1.90265 8 17.512 5.00 65.8 1.46450 9 -37.213 0.10 10 28.185 2.00 54.6 1.51454 11 54.221 (d.sub.11) 12 -50.475 2.00 25.5 1.73038 13 -17.366 1.50 52.3 1.74810 14 90.015 (d.sub.14) 15 21.344 3.00 60.3 1.51835 16 47.510 1.00 17 25.698 2.00 25.5 1.80458 18 19.106 3.20 19 -108.848 3.50 54.6 1.51454 20 -24.560 0.10 21 -1489.718 6.50 60.6 1.60311 22 -13.865 1.50 25.5 1.80458 23 -34.842 (Bf) ______________________________________ f 18.400 24.000 27.300 d6 17.323 6.811 2.987 d11 4.870 7.898 9.649 d14 8.112 5.084 3.333 Bf 42.968 48.575 51.818 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 49.794 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.89224E.sup.-05, C.sub.6 = 0.47558E.sup.-08, C.sub.8 = 0.82136E.sup.-11, C.sub.10 = 0.33662E.sup.-14 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.5816, |f.sub.1 | = 26.262 |AS-S|/fw = 0.10589 (φ = 43.33) f.sub.2 /fw = 1.9565, |f.sub.3 |/fw = 2.2581 f.sub.4 /fw = 2.0842, d.sub.23 /L = 0.3543 d.sub.4p = 6.5, |n.sub.3n -n.sub.3p | = 0.017721 6 ν.sub.3p -ν.sub.3n = -26.8, n.sub.4n -n.sub.4p = 0.20147 ν.sub.4p -ν.sub.4n = 35.1 ______________________________________ where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; fw: the focal distance of the entire system at the wide angle end; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group-and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 1 : the focal distance of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 ]+C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 8

The super wide angle zoom lens as set forth in claim 3, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 18.4˜27.3, 2ω = 101.5°˜76.4°, F.sub.NO = 4.07˜4.60 r d ν n ______________________________________ 1 90.937 2.50 45.4 1.79668 2 31.382 13.00 3 -278.297 1.50 43.4 1.84042 4 27.974 4.00 49.5 1.77279 5 30.032 8.01 6 43.281 4.70 25.5 1.80458 7 215.269 (d.sub.7).sub. 8 22.602 1.50 27.6 1.75520 9 12.892 5.00 65.8 1.46450 10 -42.867 0.10 11 27.354 2.00 70.0 1.51860 12 41.149 (d.sub.12) 13 -55.604 1.50 55.6 1.69680 14 16.631 2.00 25.5 1.73038 15 66.434 (d.sub.15) 16 17.545 3.00 25.5 1.73038 17 17.053 3.00 18 -27.216 3.00 58.5 1.65160 19 -19.139 0.10 20 97.697 9.00 65.4 1.60300 21 -11.988 1.50 25.5 1.73038 22 -33.438 (Bf) ______________________________________ f 18.399 24.000 27.300 d7 20.808 7.653 2.694 d12 3.914 6.449 7.934 d15 5.867 3.333 1.847 Bf 35.003 39.227 41.703 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 90.937 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.41120E.sup.-05, C.sub.6 = -0.10463E.sup.08, C.sub.8 = 0.26766E.sup.-12, C.sub.10 = 0.94821E.sup.-15 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.4352, |f.sub.1 | = 33.000 |AS-S|/fw = 0.12817 (φ = 55.75) f.sub.2 /fw = 1.9293, |f.sub.3 |/fw = 2.5000 f.sub.4 /fw = 1.9567 d.sub.23 /L = 0.2376 d.sub.4p = 9.0, |n.sub.3n -n.sub.3p | = 0.033578 7 ν.sub.3p -ν.sub.3n = -30.1, n.sub.4n -n.sub.4p = 0.12738 ν.sub.4p -ν.sub.4n = 39.9 ______________________________________ where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; fw: the focal distance of the entire system at the wide angle end; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 1 : the focal distance of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν3p: the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; 84 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 ]+C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 9

The super wide angle zoom lens as set forth in claim 3, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 18.4˜27.3, 2ω = 101.3°˜76.4°, F.sub.NO = 4.6 r d ν n ______________________________________ 1 48.498 1.80 39.8 1.86994 2 15.829 11.00 3 -48.419 1.50 43.3 1.84042 4 479.543 13.69 5 42.228 4.30 27.8 1.69911 6 -30.868 1.30 35.7 1.90265 7 218.115 (d.sub.7).sub. 8 44.084 1.50 33.9 1.80384 9 18.238 4.00 65.7 1.46450 10 -110.754 0.10 11 36.956 4.00 54.6 1.51454 12 -48.126 (d.sub.12) 13 -36.432 3.00 26.1 1.78470 14 -16.787 1.50 52.3 1.74810 15 164.469 (d.sub.15) 16 21.601 2.50 60.2 1.51835 17 37.689 1.00 18 23.788 2.00 25.5 1.80458 19 19.149 3.70 20 -285.297 4.00 54.6 1.51454 21 -23.565 0.20 22 115.249 7.00 82.5 1.49782 23 -16.557 1.50 25.5 1.80458 24 -43.420 (Bf) ______________________________________ f 18.400 24.000 27.300 d7 9.147 2.641 0.502 d12 6.616 10.597 12.842 d15 8.058 4.076 1.832 Bf 50.193 57.567 61.723 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 48.498 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.15694E.sup.-04, C.sub.6 = -0.11607E.sup.-07, C.sub.8 = 0.18735E.sup.-10, C.sub.10 = 0.28146E.sup.-13 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.7440, |f.sub.1 | = 20.000 |AS-S|/fw = 0.10283 (φ = 37.59) f.sub.2 /fw = 1.9565, |f.sub.3 |/fw = 2.2581 f.sub.4 /fw = 2.0841, d.sub.23 /L = 0.40755 d.sub.4p = 7.0, |n.sub.3n -n.sub.3p | = 0.036603 8 ν.sub.3p -ν.sub.3n = -26.3, n.sub.4n -n.sub.4p = 0.30676 ν.sub.4p -ν.sub.4n = 57.0 ______________________________________ where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the f-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; fw: the focal distance of the entire system at the wide angle end; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 1 : the focal distance of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r .sup.2).sup.1/2 ]+ C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 10

The super wide angle zoom lens as set forth in claim 3, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 18.4˜27.3, 2ω = 101.4°˜76.4°, F.sub.NO = 4.1 r d ν n ______________________________________ 1 43.716 2.00 39.8 1.86994 2 18.989 14.00 3 -86.359 1.60 43.4 1.84042 4 75.253 18.95 5 95.685 3.00 27.8 1.69911 6 735.641 (d.sub.6).sub. 7 24.693 1.50 35.7 1.90265 8 16.576 4.50 65.8 1.46450 9 -68.174 0.10 10 34.470 2.75 54.6 1.51454 11 -139.738 (d.sub.11) 12 -65.912 2.20 25.5 1.73038 13 -16.570 1.50 52.3 1.74810 14 36.691 (d.sub.14) 15 22.288 3.00 82.5 1.49782 16 81.627 0.30 17 33.611 2.00 25.5 1.80458 18 20.491 3.60 19 -43.822 3.50 54.6 1.51454 20 -20.698 0.10 21 77.825 7.00 82.5 1.49782 22 -18.604 1.50 23.0 1.86074 23 -38.417 (Bf) ______________________________________ f 18.400 24.000 27.300 d6 18.461 5.351 0.300 d11 4.326 6.557 7.846 d14 8.551 6.816 5.813 Bf 42.382 46.845 49.423 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 43.716 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.56396E.sup.-05, C.sub.6 = 0.31551E.sup.-08, C.sub.8 = -0.69514E.sup.-11, C.sub.10 = 0.14709E.sup.-13 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 1.0299, |f.sub.1 | = 26.262 |AS-S|/fw = 0.11679, (φ = 46.16) f.sub.2 /fw = 1.576, |f.sub.3 |/fw 32 1.644 f.sub.4 /fw = 2.283, d.sub.23 /L = 0.4791 d.sub.4p = 7.0, |n.sub.3n -n.sub.3p | = 0.017721 9 ν.sub.3p -ν.sub.3n = -26.8, n.sub.4n -n.sub.4p = 0.36292 ν.sub.4p -ν.sub.4n = 59.5 ______________________________________ where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; fw: the focal distance of the entire system at the wide angle end; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 1 : the focal distance of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 ]+C2h.sup.2 +C4 h.sup.4 +C6h.sup.6 +C8 h.sup.8 +C10 h.sup.10 ps where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 11

The super wide angle zoom lens as set forth in claim 3, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 18.4˜27.3, 2ω = 101.4°˜76.4°, F.sub.NO = 4.1 r d ν n ______________________________________ 1 66.171 2.50 40.9 1.79631 2 17.878 12.00 3 -104.815 2.00 45.4 1.79668 4 47.251 9.44 5 48.413 3.00 27.8 1.69911 6 965.152 (d.sub.6).sub. 7 32.559 1.50 35.7 1.90265 8 17.903 5.00 82.6 1.49782 9 -46.322 0.10 10 24.920 2.00 49.0 1.53172 11 38.591 (d.sub.11) 12 -45.932 2.20 25.5 1.73038 13 -14.583 1.50 55.6 1.69680 14 111.545 (d.sub.14) 15 21.650 3.00 54.6 1.51454 16 65.101 0.30 17 27.419 2.00 25.5 1.80458 18 19.163 3.00 19 300.132 3.70 54.6 1.51454 20 -28.447 0.10 21 -472.607 7.50 67.9 1.59319 22 -14.540 1.50 25.5 1.80458 23 -41.540 (Bf) ______________________________________ f 18.400 24.000 27.300 d6 17.683 7.495 3.887 d11 4.892 8.343 10.354 d14 9.792 6.341 4.330 Bf 44.471 50.862 54.586 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 66.171 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.98928E.sup.-05, C.sub.6 = -0.63815E.sup.-08, C.sub.8 = 0.86133E.sup.-11, C.sub.10 = 0.98912E.sup.-16, ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.5132, |f.sub.1 | = 26.262 |AS-S|/fw = 0.12124 (φ = 44.79) f.sub.2 /fw = 2.2826, |f.sub.3 |/fw = 2.7174 f.sub.4 /fw = 2.1091, d.sub.23 /L = 0.32626 d.sub.4p = 7.5, |n.sub.3n -n.sub.3p | = 0.03357 ν.sub.3p -ν.sub.3n = -30.1, n.sub.4n -n.sub.4p = 0.211392 ν.sub.4p -ν.sub.4n = 42.4 ______________________________________ where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius: fw: the focal distance of the entire system at the wide angle end; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 1 : the focal distance of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative, lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens-group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 ]+C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 12

A super wide angle zoom lens comprising: a front group exhibiting a negative refracting power and including, sequentially from an object, a first lens element having a negative refracting power, a second lens element having a negative refracting power and a third lens element having a positive refracting power, at least one surface of the lens elements of said front group being aspherical; and a rear group having a positive refracting power, disposed closer to the image side than said front group, the rear group including a lens group disposed closest to said front group side; wherein when variable power operation is performed from the wide angle end side to the telephoto end side, at least one of said front group and said lens group disposed closest to said front group side in said rear group moves to reduce air space on the optical axis between said front group and said rear group, and wherein said front group is constructed to satisfy the following condition:

Claim 13

A super wide angle zoom lens comprising: a front group exhibiting a negative refracting power and including, sequentially from an object, a first lens element having a negative refracting power, a second lens element having a negative refracting power and a third lens element having a positive refracting power, at least one surface of the lens elements of said front group being aspherical; and a rear group having a positive refracting power, disposed closer to the image side than said front group, the rear group including a lens group disposed closest to said front group side; wherein when variable power operation is performed from the wide angle end side to the telephoto end side, at least one of said front group and said lens group disposed closest to said front group side in said rear group moves to reduce air space on the optical axis between said front group and said rear group, and wherein said front group is constructed to satisfy the following condition:

Claim 14

25≦d 23 /fw≦1.4 where d 23 is the axial air space between the closest-to-image surface of said second lens element and the closest-to-object surface of said third lens element, and fw is the focal distance of the entire system at the wide angle end.

Claim 15

25≦d 23 /fw≦1.4 where d 23 is the axial air space between the closest-to-image surface of said second lens element and the closest-to-object surface of said third lens element, and fw is the focal distance of the entire system at the wide angle end.

Claim 16

The super wide angle zoom lens as set forth in claim 11, wherein said aspherical surface is configured to satisfy the following condition for compensating mainly a negative distortion: 0.0.≦|AS-S|/fw≦0.5 where AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; and fw: the focal distance of the entire system at the wide angle end.

Claim 17

The super wide angle zoom lens as set forth in claim 11, wherein said aspherical surface is configured to satisfy the following condition for compensating mainly a negative distortion: 0.095≦|AS-S|/fw≦0.5 where AS-S: the difference in the optical-axial direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; and fw: the focal distance of the entire system at the wide angle end.

Claim 18

A super wide angle zoom lens comprising: a front group having a first lens group including, in the order from the object side, a first lens element having a negative refracting power, a second lens element having a negative refracting power, and a third lens element having a positive refracting power, the front group having a negative refracting power as a whole, at least one surface of the lens elements of said front group being aspherical; and a rear group including, in the order from the object side, a second lens group having a positive refracting power, a third lens group having a negative refracting power and a fourth lens group having a positive refracting power, the rear group having a positive refracting power as a whole; wherein said front group is constructed to satisfy the following condition: 0.12≦d.sub.23 /fw≦2.0 where d 23 is the axial air space between a surface, closest to the image, of said second lens element and a surface, closest to the object, of said third lens element, and fw is the focal distance of the entire system at the wide angle end; and wherein when variable power operation is performed from the wide angle end side to the telephoto end side, at least two lens groups are moved along the optical axis so that air space between said first lens group and said second lens group reduces, air space between said second lens group and said third lens group increases and air space between said third lens group and said fourth lens group reduces.

Claim 19

A super wide angle zoom lens comprising: a front group having a first lens group including, in the order from the object side, a first lens element having a negative refracting power, a second lens element having a negative refracting power, and a third lens element having a positive refracting power, the front group having a negative refracting power as a whole, at least one surface of the lens elements of said front group being aspherical; and a rear group including, in the order from the object side, a second lens group having a positive refracting power, a third lens group having a negative refracting power and a fourth lens group having a positive refracting power, the rear group having a positive refracting power as a whole; wherein said front group is constructed to satisfy the following condition: 0.12≦d.sub.23 /fw≦2.0 where d 23 is the axial air space between a surface, closest to the image, of said second lens element and a surface, closest to the object, of said third lens element, and fw is the focal distance of the entire system at the wide angle end; and wherein when variable power operation is performed from the wide angle end side to the telephoto end side, at least two lens groups are moved along the optical axis so that air space between said first lens group and said second lens group reduces, air space between said second lens group and said third lens group increases and air space between said third lens group and said fourth lens group reduces.

Claim 20

The super wide angle zoom lens as set forth in claim 14, wherein said second negative lens element and said third positive lens element in said first lens group having the negative refracting power are disposed to satisfy the following condition: 0.16≦d.sub.23 /L≦0.6 where L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group.

Claim 21

The super wide angle zoom lens as set forth in claim 14, wherein said first lens group and said third lens group are constructed to satisfy the following conditions: (300/fw)≦|f.sub.1 |≦(680/fw) 1.1≦|f.sub.3 |/fw≦3.5, f.sub.3 ≦0 where f 1 : the focal distance of said first lens group; and f 3 : the focal distance of said third lens group.

Claim 22

The super wide angle zoom lens as set forth in claim 14, wherein said first lens group and said third lens group are constructed to satisfy the following conditions: (300/fw)≦|f.sub.1 |≦(680/fw) 1.5≦|f.sub.3 |/fw≦3.2, f.sub.3 ≦0 where f 1 : the focal distance of said first lens group; and f 3 : the focal distance of said third lens group.

Claim 23

The super wide angle zoom lens as set forth in claim 14, wherein said second lens group and said fourth lens group are constructed to satisfy the following conditions: 1≦f.sub.2 /fw≦5 1.4≦f.sub.4 /fw≦4 where f 2 : the focal distance of said second lens group; and f 4 : the focal distance of said fourth lens group.

Claim 24

The super wide angle zoom lens as set forth in claim 14, wherein said second lens group and said fourth lens group are constructed to satisfy the following conditions: 1.45≦f.sub.2 /fw≦3 1.7≦f.sub.4 /fw ≦3.0 where f 2 : the focal distance of said second lens group; and f 4 : the focal distance of said fourth lens group.

Claim 25

The super wide angle zoom lens as set forth in claim 14, wherein said third lens group having the negative refracting power includes a joint negative lens element consisting of positive and negative lenses joined to each other, said fourth lens group having the positive refracting power includes a joint positive lens element consisting of positive and negative lenses joined to each other on the closest-to-image side, and said third and fourth lens groups are constructed to satisfy the following conditions: (60/fw)≦d.sub.4p p≦(185/fw) |n.sub.3 n-n.sub.3p |≦0.13 3150≦ν.sub.3p -ν.sub.3n ≦-20 0.1≦n.sub.4n -n.sub.4p ≦0.4 25ν.sub.4p -ν.sub.4n where d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν3n: The Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; and ν4n: the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group.

Claim 26

A super wide angle zoom lens comprising: a front group having a first lens group including, in the order from the object side, a first negative lens element, a second negative lens element and a third positive lens element, said first lens group exhibiting a negative refracting power and having at least one aspherical surface; and a rear group including at least a second lens group sequentially disposed toward an image of said first lens group and exhibiting a positive refracting power, a third lens group exhibiting a negative refracting power and a fourth lens group exhibiting a positive refracting power; wherein said first lens group is constructed to satisfy the following condition: (300/fw)≦|f.sub.1 |≦(680/fw) where f 1 is the focal distance of said first lens group, and fw is the focal distance of the whole system at the wide angle end; and wherein when focusing on object points from infinity to shortest distance is performed, at least one lens group in said second, third and fourth lens groups in said rear group moves along the optical axis, and when variable power operation from the wide angle end side to the telephoto end side is performed, at least two lens groups move along the optical axis so that air space between said first lens group and said second lens group reduces, air space between said second lens group and said third lens group increases and air space between said third lens group and said fourth lens group reduces.

Claim 27

A super wide angle zoom lens comprising: a front group having a first lens group including, in the order from the object side, a first negative lens element, a second negative lens element and a third positive lens element, said first lens group exhibiting a negative refracting power and having at least one aspherical surface; and a rear group including at least a second lens group sequentially disposed toward an image of said first lens group and exhibiting a positive refracting power, a third lens group exhibiting a negative refracting power and a fourth lens group exhibiting a positive refracting power; wherein said first lens group is constructed to satisfy the following condition: (300/fw)≦|f.sub.1 |≦(680/fw) where f 1 is the focal distance of said first lens group, and fw is the focal distance of the whole system at the wide angle end; and wherein when focusing on object points from infinity to shortest distance is performed, at least one lens group in said second, third and fourth lens groups in said rear group moves along the optical axis, and when variable power operation from the wide angle end side to the telephoto end side is performed, at least two lens groups move along the optical axis so that air space between said first lens group and said second lens group reduces, air space between said second lens group and said third lens group increases and air space between said third lens group and said fourth lens group reduces.

Claim 28

The super wide angle zoom lens as set forth in claim 21, wherein said front group is constructed to satisfy the following condition: 0.12≦d.sub.23 /fw≦2.0 where d 23 is the axial air space between a surface, closest to the image, of said second lens element and a surface, closest to the object, of said third lens element.

Claim 29

The super wide angle zoom lens as set forth in claim 21, wherein said first lens group is constructed to satisfy the following condition: 0.25≦d.sub.23 /fw≦1.4 where d 23 is the axial air space between the closest-to-image surface of said second lens element and the closest-to-object surface of said third lens element, and fw is the focal distance of the entire system at the wide angle end.

Claim 30

The super wide angle zoom lens as set forth in claim 21, wherein said aspherical surface is configured to satisfy the following condition for compensating mainly a negative distortion: 0.01≦|AS-S|/fw≦0.5 where AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius.

Claim 31

The super wide angle zoom lens as set forth in claim 21, wherein said aspherical surface is configured to satisfy the following condition for compensating mainly a negative distortion: 0.095≦|AS-S|/fw 0.5 where AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius.

Claim 32

The super wide angle zoom lens as set forth in claim 21, wherein said third lens group is constructed to satisfy the following condition: (300/fw)≦|f.sub.1 ≦(680/fw) 1.1≦|f.sub.3 |/fw≦3.5, f.sub.3 <0 where f 3 : the focal distance of said third lens group.

Claim 33

The super wide angle zoom lens as set forth in claim 21, wherein said third lens group is constructed to satisfy the following condition: 1.5≦|f.sub.3 |/fw≦3.2, f.sub.3 <0 where f 3 : the focal distance of said third lens group.

Claim 34

The super wide angle zoom lens as set forth in claim 21, wherein said second lens group and said fourth lens group are constructed to satisfy the following conditions: 1≦f.sub.2 /fw≦5 1.4≦f.sub.4 /fw≦4 where f 2 : the focal distance of said second lens group; and f 4 : the focal distance of said fourth lens group.

Claim 35

The super wide angle zoom lens as set forth in claim 21, wherein said second lens group and said fourth lens group are constructed to satisfy the following conditions: 1.45≦f.sub.2 /fw≦3 1.7≦f.sub.4 /fw≦3.0 where f 2 : the focal distance of said second lens group; and f 4 : the focal distance of said fourth lens group.

Claim 36

The super wide angle zoom lens as set forth in claim 21, wherein said second negative lens element and said third positive lens element in said first lens group having the negative refracting power are disposed to satisfy the following condition: 0.16≦d.sub.23 /L≦0.6 where d 23 :the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group.

Claim 37

The super wide angle zoom lens as set forth in claim 21, wherein a lens group moved for focusing in said rear group is constructed to satisfy the following condition: βw≦-1.1 or βw≈-0.9 where βw is the image forming magnification at the wide angle end.

Claim 38

The super wide angle zoom lens as set forth in claim 21, wherein said third lens group having the negative refracting power in said rear group is moved for focusing and is constructed to move towards the image along the optical axis on the occasion of focusing from the infinity object point to the shortest distance object point, said third lens group being constructed to satisfy the following condition: βw≦-1.1 or βw≈-0.9 where βw is the image forming magnification of said third lens group at the wide angle end.

Claim 39

The super wide angle zoom lens as set forth in claim 21, wherein said third lens group and said fourth lens group in said rear group are moved for focusing and are constructed to move toward the object along the optical axis on the occasion of focusing from the infinity object point to the shortest distance object point, said third and fourth lens groups being also constructed to satisfy the following condition: βw≦-1.1 or βw≈-0.9 where βw is the synthetic image forming magnification of said third and fourth lens groups at the wide angle end.

Claim 40

The super wide angle zoom lens as set forth in claim 21, wherein said third lens group having the negative refracting power includes a joint negative lens element consisting of positive and negative lenses joined to each other, said fourth lens group having the positive refracting power includes a joint positive lens element consisting of positive and negative lenses joined to each other on the closest-to-image side, and said third and fourth lens groups are constructed to satisfy the following conditions: (60/fw)≦d.sub.4p ≦(185/fw) |n.sub.3n -n.sub.3p |≦0.13 -50≦ν.sub.3p -ν.sub.3n ≦-20 0.1≦n.sub.4n -n.sub.4p ≦0.4 25≦ν.sub.4p -ν.sub.4n where d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens-element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; and ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group.

Claim 41

The super wide angle zoom lens as set forth in claim 21, wherein said third lens group exhibiting the negative refracting power includes a joint negative lens element consisting of positive and negative lenses joined to each other, and said fourth lens group exhibiting the positive refracting power includes a joint positive lens element consisting of positive and negative lenses joined to each other on the closest-to-image-side.

Claim 42

The super wide angle zoom lens as set forth in claim 35, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 15.5˜27.3, 2ω = 111.2°˜76.4°, F.sub.NO = 4.1 r d ν n ______________________________________ 1 69.600 2.50 45.4 1.79668 2 20.275 15.50 3 -80.398 2.00 45.4 1.79668 4 37.112 6.00 5 46.526 5.30 35.2 1.74950 6 -815.420 (d.sub.6).sub. 7 26.848 1.60 33.9 1.80384 8 14.972 4.50 65.8 1.46450 9 97.280 0.20 10 38.990 3.00 41.4 1.57501 11 -50.400 (d.sub.11) 12 -36.378 2.30 28.3 1.72825 13 -13.883 1.50 55.6 1.69680 14 128.521 (d.sub.14) 15 24.647 3.00 54.6 1.51454 16 73.993 0.50 17 41.947 2.00 26.1 1.78470 18 24.197 3.20 19 -103.008 3.00 67.9 1.59319 20 -28.765 0.10 21 217.566 8.00 65.4 1.60300 22 -15.505 2.00 23.0 1.86074 23 -30.196 (Bf) ______________________________________ f 15.450 24.000 27.300 D0 ∞ ∞ ∞ d6 21.412 3.704 0.398 d11 6.575 11.685 13.610 d14 7.671 2.561 0.636 Bf 38.211 47.501 51.002 β -0.033 -0.033 -0.033 D0 446.493 701.446 792.896 d6 21.412 3.704 0.398 d11 6.575 10.640 12.031 d14 7.117 2.445 1.000 Bf 38.765 48.662 52.217 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 69.600 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.79789E.sup.-05, C.sub.6 = -0.39445E.sup.-08, C.sub.8 = 0.24046E.sup.-11, C.sub.10 = 0.31560E.sup.-14 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.388, |f.sub.1 | = 24.942 |AS-S|/fw = 0.25367 (φ = 55.66) βw = -0.6702, f.sub.2 /fw = 2.330 |f.sub.3 |/fw = 2.773, f.sub.4 /fw = 2.307 d.sub.23 /L = 0.192 d.sub.4p = 8.0 |n.sub.3n -n.sub.3p | = 0.03145 ν.sub.3p -ν.sub.3n = -27.3 n.sub.4n -n.sub.4p = 0.2577, ν.sub.4p -ν.sub.4n ______________________________________ = 42.4 where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; DO is the distance from the object to be photographed to the first surface of the lens, and β is the short distance image forming magnification; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; d 23 : the axial air spacing between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; βw: the image forming magnification at the wide angle end, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 ]+C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 43

The super wide angle zoom lens as set forth in claim 35, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 16.4˜27.3, 2ω = 108.2°˜76.4°, F.sub.NO = 4.1 r d ν n ______________________________________ 1 56.830 2.50 45.4 1.79668 2 22.588 13.00 3 203.239 2.00 43.4 1.84042 4 29.159 14.20 5 29.712 3.50 25.5 1.80458 6 37.859 (d.sub.6).sub. 7 35.294 1.30 33.9 1.80384 8 16.316 4.00 70.4 1.48749 9 160.741 0.20 10 35.749 3.00 38.0 1.60342 11 -53.604 (d.sub.11) 12 -30.014 2.50 27.8 1.69911 13 -12.979 1.50 60.0 1.64000 14 141.313 (d.sub.14) 15 29.674 3.50 58.9 1.51823 16 -229.981 0.10 17 92.266 2.00 28.6 1.79504 18 28.825 2.50 19 -150.071 3.00 65.4 1.60300 20 -34.756 0.10 21 205.091 8.00 57.5 1.67025 22 -15.837 1.80 23.0 1.86074 23 -34.904 (Bf) ______________________________________ f 16.400 24.000 27.300 D0 ∞ ∞ ∞ d6 18.553 4.145 0.916 d11 8.282 13.087 15.115 d14 7.722 2.917 0.888 Bf 39.789 47.798 51.178 β -0.033 -0.033 -0.033 D0 474.300 695.693 786.445 d6 18.553 4.145 0.916 d11 8.276 11.785 13.299 d14 7.127 3.035 1.493 Bf 40.389 48.979 52.388 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 56.830 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.41777E.sup.-05, C.sub.6 = 0.36563E.sup.-09, C.sub.8 = -0.98160E.sup.-12, C.sub.10 = 0.21972E.sup.-14 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.8659, |f.sub.1 | = 24.941 |AS-S|/fw = 0.1800 (φ = 55.73) βw = -0.6557, f.sub.2 /fw = 2.195 |f.sub.3 |/fw = 2.612, f.sub.4 /fw = 2.174 d.sub.23 /L = 0.4034, d.sub.4p = 8.0 |n.sub.3n -n.sub.3p | = 0.05911, ν.sub.3p -ν.sub.3 n = -32.2 n.sub.4n -n.sub.4p = 0.19049, ν.sub.4p -ν.sub.4n ______________________________________ = 34.5 where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; DO is the distance from the object to be photographed to the first surface of the lens, and β is the short distance image forming magnification; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; βw: the image forming magnification at the wide angle end, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 9 +C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 44

The super wide angle zoom lens as set forth in claim 35, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 18.4˜27.3, 2ω = 101.2°˜76.4°, F.sub.NO = 4.1 r d ν n ______________________________________ 1 49.794 2.50 40.9 1.79631 2 17.702 12.00 3 -83.638 2.00 45.4 1.79668 4 47.407 10.70 5 50.613 3.00 27.8 1.69911 6 511.053 (d.sub.6).sub. 7 28.622 1.50 35.7 1.90265 8 17.512 5.00 65.8 1.46450 9 -37.213 0.10 10 28.185 2.00 54.6 1.51454 11 54.221 (d.sub.11) 12 -50.475 2.00 25.5 1.73038 13 -17.366 1.50 52.3 1.74810 14 90.015 (d.sub.14) 15 21.344 3.00 60.3 1.51835 16 47.510 1.00 17 25.698 2.00 25.5 1.80458 18 19.106 3.20 19 -108.848 3.50 54.6 1.51454 20 -24.560 0.10 21 -1489.718 6.50 60.6 1.60311 22 -13.865 1.50 25.5 1.80458 23 -34.842 (Bf) ______________________________________ f 18.400 24.000 27.300 D0 ∞ ∞ ∞ d6 17.323 6.811 2.987 d11 4.870 7.898 9.649 d14 8.112 5.084 3.333 Bf 42.968 48.575 51.818 β -0.033 -0.033 -0.033 D0 538.530 700.241 786.818 d6 17.323 6.811 2.987 d11 4.869 6.528 7.240 d14 7.414 4.932 3.889 Bf 43.668 50.098 53.671 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 49.794 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.89224E.sup.-05, C.sub.6 = -0.57558E.sup.-08, C.sub.8 = 0.82136E.sup.-11, C.sub.10 = 0.33662E.sup.-14 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.5816, |f.sub.1 | = 26.262 |AS-S|/fw = 0.10589, (φ = 43.33) βw = -0.7518, f.sub.2 /fw = 1.9565 |f.sub.3 |/fw = 2.2581, f.sub.4 /fw = 2.0842 d.sub.23 /L = 0.3543, d.sub.4p = 6.5 |n.sub.3n -n.sub.3p | = 0.017721, ν.sub.3p -ν.sub. 3n = -26.8 n.sub.4n -n.sub.4p = 0.20147, ν.sub.4p -ν.sub.4n ______________________________________ = 35.1 where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; DO is the distance from the object to be photographed to the first surface of the lens, and β is the short distance image forming magnification; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group, βw: the image forming magnification at the wide angle end, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 ]+C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 45

The super wide angle zoom lens as set forth in claim 35, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 18.4˜27.3, 2ω = 101.5°˜76.4°, F.sub.NO = 4.7˜4.60 r d ν n ______________________________________ 1 90.937 2.50 45.4 1.79668 2 31.382 13.00 3 -278.297 1.50 43.4 1.84042 4 27.974 4.00 49.5 1.77279 5 30.032 8.01 6 43.281 4.70 25.5 1.80458 7 215.269 (d.sub.7).sub. 8 22.602 1.50 2.76 1.75520 9 12.892 5.00 65.8 1.46450 10 -42.867 0.10 11 27.354 2.00 70.0 1.51860 12 41.149 (d.sub.12) 13 -55.604 1.50 55.6 1.69680 14 16.631 2.00 25.5 1.73038 15 66.434 (d.sub.15) 16 17.545 3.00 25.5 1.73038 17 17.053 3.00 18 -27.216 3.00 58.5 1.65160 19 -19.139 0.10 20 97.697 9.00 65.4 1.60300 21 -11.988 1.50 25.5 1.73038 22 -33.438 (Bf) ______________________________________ f 18.399 24.000 27.300 D0 ∞ ∞ ∞ d7 20.808 7.653 2.694 d12 3.914 6.449 7.934 d15 5.867 3.333 1.847 Bf 35.003 39.227 41.703 β -0.033 -0.033 -0.033 D0 533.258 693.544 780.668 d7 20.808 7.653 2.694 d12 3.908 4.835 5.121 d15 5.246 3.479 2.785 Bf 35.630 40.693 43.578 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 90.937 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.41120E.sup.-05, C.sub.6 = -0.10463E.sup.-08, C.sub.8 = 0.26766E.sup.-12, C.sub.10 = 0.94821E.sup.-15 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.4352, |f.sub.1 | = 33.000 |AS-S|/fw = 0.12817 (φ = 55.75) βw = -0.7116, f.sub.2 /fw = 1.9293 |f.sub.3 |/fw = 2.5000, f.sub.4 /fw = 1.9567 d.sub.23 /L = 0.2376, d.sub.4p = 9.0 |n.sub.3n -n.sub.3p | = 0.033578, ν.sub.3p -ν.sub. 3n = -30.1 n.sub.4n -n.sub.4p = 0.12738, ν.sub. 4p -ν.sub.4n ______________________________________ = 39.9 where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; DO is the distance from the object to be photographed to the first surface of the lens, and β is the short distance image forming magnification; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n4n: the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; βw: the image forming magnification at the wide angle end, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 ]+C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 46

The super wide angle zoom lens as set forth in claim 35, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 18.4˜27.3, 2ω = 101.3°˜76.4°, F.sub.NO = 4.6 r d ν n ______________________________________ 1 48.498 1.80 39.8 1.86994 2 15.829 11.00 3 -48.419 1.50 43.3 1.84042 4 479.543 13.69 5 42.228 4.30 27.8 1.69911 6 -30.868 1.30 35.7 1.90265 7 218.115 (d.sub.7).sub. 8 44.084 1.50 33.9 1.80384 9 18.238 4.00 65.7 1.46450 10 -110.754 0.10 11 36.956 4.00 54.6 1.51454 12 -48.126 (d.sub.12) 13 -36.432 3.00 26.1 1.78470 14 -16.787 1.50 52.3 1.74810 15 164.469 (d.sub.15) 16 21.601 2.50 60.2 1.51835 17 37.689 1.00 18 23.788 2.00 25.5 1.80458 19 19.149 3.70 20 -285.297 4.00 54.6 1.51454 21 -23.565 0.20 22 115.249 7.00 82.5 1.49782 23 -16.557 1.50 25.5 1.80458 24 -43.420 (Bf) ______________________________________ f 18.400 24.000 27.300 D0 ∞ ∞ ∞ d7 9.147 2.641 0.502 d12 6.616 10.597 12.842 d15 8.058 4.076 1.832 Bf 50.193 57.567 61.723 β -0.033 -0.033 -0.033 D0 546.246 705.614 792.210 d7 9.147 2.641 0.502 d12 6.607 9.414 11.227 d15 7.135 3.944 2.370 Bf 51.125 58.882 62.799 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 48.498 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.15694E.sup.-04, C.sub.6 = -0.11607E.sup.-07, C.sub.8 = 0.18735E.sup.-10, C.sub.10 = 0.28146E.sup.-13 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.7440, |f.sub.1 | = 20.000 |AS-S|/fw = 0.10283 (φ = 37.59) βw = -0.6355, f.sub.2 /fw = 1.9565 |f.sub.3 |/fw = 2.2581, f.sub.4 /fw = 2.0841 d.sub.23 /L = 0.40755, d.sub.4p = 7.0 |n.sub.3n -n.sub.3p | = 0.036603, ν.sub.3p -ν.sub. 3n = -26.3 n.sub. 4n -n.sub.4p = 0.30676 ν.sub.4p -ν.sub.4n = 57.0 ______________________________________ where the leftmost numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; DO is the distance from the object to be photographed to the first surface of the lens, and β is the short distance image forming magnification; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; d 23 : the axial between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative-lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; βw: the image forming magnification at the wide angle end, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 ]+C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 47

The super wide angle zoom lens as set forth in claim 25, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 18.4˜27.3, 2ω = 101.4°˜76.4°, F.sub.NO = 4.1 r d ν n ______________________________________ 1 43.716 2.00 39.8 1.86994 2 18.989 14.00 3 -86.359 1.60 43.4 1.84042 4 75.253 18.95 5 95.685 3.00 27.8 1.69911 6 735.641 (d.sub.6).sub. 7 24.693 1.50 35.7 1.90265 8 16.576 4.50 65.8 1.46450 9 -68.174 0.10 10 34.470 2.75 54.6 1.51454 11 -139.738 (d.sub.11) 12 -65.912 2.20 25.5 1.73038 13 -16.570 1.50 52.3 1.74810 14 36.691 (d.sub.14) 15 22.288 3.00 82.5 1.49782 16 81.627 0.30 17 33.611 2.00 25.5 1.80458 18 20.491 3.60 19 -43.822 3.50 54.6 1.51454 20 -20.698 0.10 21 77.825 7.00 82.5 1.49782 22 -18.604 1.50 23.0 1.86074 23 -38.417 (Bf) ______________________________________ f 18.400 24.000 27.300 D0 ∞ ∞ ∞ d7 18.461 5.351 0.300 d11 4.326 6.557 7.846 d14 8.551 6.816 5.813 Bf 42.382 46.845 49.423 β -0.033 -0.033 -0.033 D0 535.971 709.394 812.035 d6 18.461 5.351 0.300 d11 4.671 7.023 8.385 d14 8.206 6.350 5.274 Bf 42.382 46.845 49.423 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 43.716 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.56396E.sup.-05, C.sub.6 = 0.31551E.sup.-08, C.sub.8 = -0.69514E.sup.-11, C.sub.10 = 0.14709E.sup.-13 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 1.0299, |f.sub.1 | = 26.262 |AS-S|/fw = 0.11679 (φ = 46.16) βw = -6.5185, f.sub.2 /fw = 1.576 |f.sub.3 |/fw = 1.644, f.sub.4 /fw = 2.283 d.sub.23 /L = 0.4791, d.sub.4p = 7.0 |n.sub.3n -n.sub.3p | = 0.017721, ν.sub.3p -ν.sub. 3n = -26.8 n.sub.4n -n.sub.4p = 0.36292, ν.sub.4p -ν.sub.4n ______________________________________ = 59.5 where the left most numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; DO is the distance from the object to be photographed to the first surface of the lens, and β is the short distance image forming magnification; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 1 : the focal distance of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; 84 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; βw: the image forming magnification at the wide angle end, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2)1/2]+C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .

Claim 48

The super wide angle zoom lens as set forth in claim 35, wherein said zoom lens is constructed based on the data of the following table: ______________________________________ f = 18.4˜27.3, 2ω = 101.4°˜76.4°, F.sub.NO = 4.1 r d ν n ______________________________________ 1 66.171 2.50 40.9 1.79631 2 17.878 12.00 3 -104.815 2.00 45.4 1.79668 4 47.251 9.44 5 48.413 3.00 27.8 1.69911 6 965.152 (d.sub.6).sub. 7 32.559 1.50 35.7 1.90265 8 17.903 5.00 82.6 1.49782 9 -46.322 0.10 10 24.920 2.00 49.0 1.53172 11 38.591 (d.sub.11) 12 -45.932 2.20 25.5 1.73038 13 -14.583 1.50 55.6 1.69680 14 111.545 (d.sub.14) 15 21.650 3.00 54.6 1.51454 16 65.101 0.30 17 27.419 2.00 25.5 1.80458 18 19.163 3.00 19 300.132 3.70 54.6 1.51454 20 -28.447 0.10 21 -472.607 7.50 67.9 1.59319 22 -14.540 1.50 25.5 1.80458 23 -41.540 (Bf) ______________________________________ f 18.400 24.000 27.300 D0 ∞ ∞ ∞ d6 17.683 7.495 3.887 d11 4.892 8.343 10.354 d14 9.792 6.341 4.330 Bf 44.471 50.862 54.586 β -0.033 -0.033 -0.033 D0 541.063 699.052 793.913 d6 17.683 7.495 3.887 d11 4.885 7.045 8.805 d14 9.060 6.640 4.911 Bf 45.210 51.861 55.554 ______________________________________ Aspherical Surface (First Surface) ______________________________________ Reference Paraxial Curvature Radius: r = 66.171 Conical Coefficient: k = 1 Aspherical Surface Coefficient C.sub.2 = 0.0, C.sub.4 = 0.98928E.sup.-05, C.sub.6 = -0.63815E.sup.-08, C.sub.8 = 0.86133E.sup.-11, C.sub.10 = 0.98912E.sup.-16 ______________________________________ Conditional Formula Corresponding Values ______________________________________ d.sub.23 /fw = 0.5132, |f.sub.1 | = 26.262 |AS-S|/fw = 0.12124 (φ = 44.79) βw = -0.5443, f.sub.2 /fw = 2.2826 |f.sub.3 |/fw = 2.7174, f.sub.4 /fw = 2.1091 d.sub.23 /L = 0.32626, d.sub.4p = 7.5 |n.sub.3n -n.sub.3p | = 0.03357, ν.sub.3p -ν.sub.3 n = -30.1 n.sub.4n -n.sub.4p = 0.211392, ν.sub.4p -ν.sub.4n ______________________________________ = 42.4 where the left most numeral in the Table indicates the order from the object, r is the curvature radius of the lens surface, d is the lens surface spacing, ν is the Abbe number, n is the refractive index in the d-line (λ=587.6 nm), f is the focal distance of the whole system, F NO is the F-number, 2ω is the view angle, and φ is the effective diameter of the aspherical surface lens; DO is the distance from the object to be photographed to the first surface of the lens, and β is the short distance image forming magnification; AS-S: the difference in the optical-axis direction between said aspherical surface in an effective diameter outermost periphery and a reference spherical surface having a predetermined vertex curvature radius; d 23 : the axial air space between the closest-to-image surface of said second lens element in said first lens group and the closest-to-object surface of said third lens element; and L: the axial thickness (distance between a lens vertex of the close-to-object surface of the closest-to-object lens in said first lens group and a lens vertex of the close-to-image surface of the closest-to-image lens in said first lens group) of said first lens group; f 2 : the focal distance of said second lens group; f 3 : the focal distance of said third lens group; f 4 : the focal distance of said fourth lens group; d 4p : the axial thickness of the positive lens in the joint positive lens element positioned closest to the image in said fourth lens group; n 3n : the refractive index to a d-line (587.6 nm) of the negative lens of the joint negative lens element in said third lens group; n 3p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint negative lens element in said third lens group; ν 3p : the Abbe number of the positive lens of the joint negative lens element in said third lens group; ν 3n : the Abbe number of the negative lens of the joint negative lens element in said third lens group; n 4n : the refractive index to the d-line (587.6 nm) of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; n 4p : the refractive index to the d-line (587.6 nm) of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens, group; ν 4p : the Abbe number of the positive lens of the joint positive lens element positioned closest to the image in said fourth lens group; ν 4n : the Abbe number of the negative lens of the joint positive lens element positioned closest to the image in said fourth lens group; βw: the image forming magnification at the wide angle end, and further, the aspherical surface shown by values of the items is expressed such as: X (h)=(h.sup.2 /r)/[1+(1-Kh.sup.2 /r.sup.2).sup.1/2 ]+C2 h.sup.2 +C4 h.sup.4 +C6 h.sup.6 +C8 h.sup.8 +C10 h.sup.10 where X(h) is the distance along the optical-axis direction from the nodal plane of the vertex of each aspherical surface at a height y in the vertical direction from the optical axis, r is the reference paraxial curvature radius, k is the conical coefficient, Cn is the n-order aspherical surface coefficient, and E -n at the left end in the n-order aspherical surface coefficient Cn indicates 10 -n .