Telephoto zoom lens

Claim 2

A telephoto zoom lens, when viewed from the object, comprises: a first lens group having positive refracting power; a second lens group having negative refracting power; a third lens group having positive refracting power; fourth lens group having positive retracting power; and a fifth lens group having negative refracting power, wherein, when magnification is varied from the wide angle end to the telephoto end, an air interval between said first lens group and said second lens group is enlarged, an air interval between said second lens group and said third lens group is reduced, an air interval between said third lens group and said fourth lens group is enlarged and an air interval between said fourth lens group and said fifth lens group is reduced; and wherein, assuming than the focal distance of the overall system at said wide angle end is f W , the air inteal from the apex of the lens surface of said third lens group G 3 which is most adjacent of the image at said telephoto end to the apex of the lens surface of said fourth lens group G 4 which is most adjacent to said object is D 3T and the air interval from the apex of the lens surface of said third lens group G 3 which is most adjacent to said image at said wide angle end to the apex of the lens surface of said fourth lens group G 4 which is most adjacent to said object is D 3W , said third lens group and said fourth lens group are constituted so as to meet the following relationship: ##EQU8##

Claim 3

A telephoto zoom lens according to claim 1, wherein, assuming that the synthesized focal distance of said second lens group and said third lens group at said telephoto end is f 23 and the synthesized focal distance of said fourth lens group and said fifth lens group is f 45 , said second to fifth lens groups are constituted in such a manner that their synthesized focal distance meets the following conditions: f.sub.23 <0, f.sub.45 <0,

Claim 4

A telephoto zoom lens according to claim 1, wherein, assuming that the synthesized focal distance of said second lens group and said third lens group at said telephoto end is f 23 , the synthesized focal distance of said fourth lens group and said fifth lens group is f 45 and the synthesized focal distance of said second lens group, said third lens group, said fourth lens group and said fifth lens group is f 25 , said second to said fifth lens groups are constituted so as to meet the following conditions: ##EQU9##

Claim 5

A telephoto zoom lens according to claim 3, wherein the synthesized focal distance f 23 of said second lens group and said third lens group at said telephoto end and the synthesized focal distance f 45 of said fourth lens group and said fifth lens group are constituted so as meet the following conditions: ##EQU10##

Claim 6

A telephoto zoom lens according to claim 1, wherein, assuming that the focal distance of the overall system at said wide angle end is f W , the focal distance of said third lens group is f 3 , the focal distance of said fourth lens group is f 4 and the focal distance of said fifth lens group is f 5 , said third, fourth and fifth lens groups are constituted so as to meet the following conditions: ##EQU11##

Claim 7

A telephoto zoom lens according to claim 5, wherein, assuming that the focal distance of the overall system at said wide angle end is f W , the focal distance of said first lens group is f 1 and the focal distance of said second lens group is f 2 , said first and second lens groups are constituted so as to meet the following conditions: ##EQU12##

Claim 8

A telephoto zoom lens according to claim 1, wherein said third lens group includes a positive lens positioned most adjacent to said image and, assuming that the curvature radius of the lens surface of said positive lens adjacent to an object is ra and the curvature radius of the lens surface adjacent to said image is r b , it is constituted so as to meet the following condition: ##EQU13##

Claim 9

A telephoto zoom lens according to claim 1, wherein, said fourth lens group includes a laminated lens consisting of a negative lens and a positive lens laminated to each other and, assuming that the refraction rate of said negative lens in said laminated lens with respect to line d is n 4n and the refraction rate of said positive lens with respect to said line d is n 4p , it is constituted so as to meet the following condition. 0.1≦n.sub.4n -n.sub.4p ≦0.5

Claim 10

A telephoto zoom lens according to claim 1, wherein the following numerical data are provided: ______________________________________ Focal distance f: 80 to 200, F-number: 4.6 Field Angle: 30.4° to 11.8° ______________________________________ r d Abbe n ______________________________________ 1 110.672 3.50 64.1 1.51680 2 218.033 0.10 3 69.139 2.40 25.4 1.80518 4 44.750 7.80 64.1 1.51680 5 -645.765 (variable) 6 -76.596 1.60 50.7 1.69350 7 41.745 3.50 25.4 1.80518 8 155.995 2.00 9 -87.570 1.60 55.6 1.69680 10 -695.191 (variable) 11 -840.520 3.43 58.5 1.61272 12 -48.249 (variable) 13 42.000 5.50 57.0 1.62280 14 -38.235 1.70 25.4 1.80518 15 -343.786 (variable) 16 106.734 4.00 35.2 1.74950 17 -35.000 2.00 53.9 1.71300 18 28.115 (Bf) ______________________________________ f 80.0000 105.0000 199.9998 ______________________________________ d5 2.3789 16.8784 48.5939 d10 35.9129 25.6780 5.1028 d12 2.1079 6.3724 17.5129 d15 20.8928 18.4686 0.4731 Bf 46.4329 48.8571 66.8526 ds 33.3156 23.0807 2.5055 ______________________________________ where r denotes curvature radius of the lens, d denotes the thickness of the lens and the interval between lens surfaces, n denotes the refraction rate, the Abbe's number and the refraction rate n are the values with respect to line d, symbol ds denotes the distance from the apex of the lens surface of said second lens group which is most adjacent to said image to the diaphragm.

Claim 11

A telephoto zoom lens according to claim 1, wherein the following numerical data are provided: ______________________________________ Focal distance f: 102 to 292, F-number: 5.7 Field Angle: 23.6° to 8.2° ______________________________________ r d Abbe n ______________________________________ 1 110.997 3.50 49.0 1.53172 2 294.483 0.10 3 70.166 2.00 23.0 1.86074 4 46.387 9.50 54.6 1.51454 5 -3821.326 (variable) 6 -75.691 1.80 45.4 1.79668 7 33.777 1.80 8 36.790 3.70 27.6 1.75520 9 373.799 (variable) 10 -121.678 3.00 70.4 1.48749 11 -36.806 (variable) 12 45.927 4.50 82.5 1.49782 13 -37.210 1.50 33.9 1.80384 14 -108.341 (variable) 15 -483.083 2.70 26.1 1.78470 16 -46.198 1.80 53.9 1.71300 17 35.955 (Bf) ______________________________________ f 102.0011 199.9884 292.0030 ______________________________________ d5 2.0772 39.1733 59.3988 d9 42.7123 18.5488 4.8410 d11 1.2855 14.2334 20.7357 d14 38.5035 20.5855 1.5779 Bf 41.1257 59.0280 78.0509 ds 40.0624 15.8989 2.1911 ______________________________________ where r denotes curvature radius of the lens, d denotes the thickness of the lens and the interval between lens surfaces, n denotes the refraction ate, the Abbe's number and the refraction rate n are the values with respect to line d, symbol ds denotes the distance from the apex of the lens surface of said second lens group which is most adjacent to said image to the diaphragm.

Claim 12

A telephoto zoom lens according to claim 1, wherein the following numerical data are provided: ______________________________________ Focal distance f: 102 to 292, F-number: 4.6 to 5.7 Field Angle: 24.0° to 8.2° ______________________________________ r d Abbe n ______________________________________ 1 99.713 4.00 64.1 1.51680 2 225.037 0.10 3 67.093 2.50 23.0 1.86074 4 45.153 10.50 54.6 1.51454 5 15051.901 (variable) 6 -89.484 1.80 49.4 1.77279 7 38.204 2.70 8 42.772 4.30 27.6 1.75520 9 207.568 (variable) 10 -297.330 4.20 82.5 1.49782 11 -46.336 (variable) 12 48.606 5.15 64.1 1.51680 13 -45.148 1.50 28.6 1.79504 14 -143.792 (variable) 15 -225.706 3.00 25.5 1.80458 16 -35.303 1.80 45.4 1.79668 17 47.108 (Bf) ______________________________________ f 102.0002 199.9998 291.9997 ______________________________________ d5 2.3471 31.7951 46.1143 d9 49.4948 20.0467 5.7275 d11 1.8983 25.4568 39.3063 d14 36.5889 18.9029 1.5223 Bf 39.9426 57.6284 75.0089 ds 46.2948 16.8467 2.5275 ______________________________________ where r denotes curvature radius of the lens, d denotes the thickness of the lens and the interval between lens surfaces, n denotes the refraction rate, the Abbe's number and the refraction rate n are the values with respect to lin d, symbol ds denotes the distance from the apex of the lens surface of said second lens group which is most adjacent to said image to the diaphragm.

Claim 13

A telephoto zoom lens according to claim 1, wherein the following numerical data are provided: ______________________________________ Focal distance f: 102 to 388, F-number: 5.7 to 8.0 Field Angle: 23.8° to 6.2° ______________________________________ r d Abbe n ______________________________________ 1 76.053 4.00 54.6 1.51454 2 273.365 0.10 3 79.449 1.60 35.7 1.90265 4 47.968 7.50 82.5 1.49782 5 611.314 (variable) 6 -75.740 1.50 43.3 1.84042 7 37.159 1.80 8 38.932 3.50 27.8 1.69911 9 -1850.633 (variable) 10 -143.797 3.00 82.5 1.49782 11 -40.716 (variable) 12 45.004 4.50 82.5 1.49782 13 -46.200 1.30 35.7 1.90265 14 -133.998 (variable) 15 -355.098 2.35 25.5 1.73038 16 -42.542 1.30 52.3 1.74810 17 40.938 (Bf) ______________________________________ f 102.0047 250.0017 387.9986 ______________________________________ d5 2.1439 51.4283 77.1678 d9 53.9750 19.6458 8.9607 d11 1.7434 20.7774 21.7498 d14 48.2818 25.3248 0.5598 Bf 37.4736 60.4301 85.1945 ds 51.9750 17.6459 6.9607 ______________________________________ where rr denotes curvature radius of the lens, d denotes the thickness of the lens and the interval between lens surfaces, n denotes the refraction ate, the Abbe's number and the refraction rate n are the values with respect to line d, symbol ds denotes the distance from the apex of the lens surface of said second lens group which is most adjacent to said image to the diaphragm.

Claim 14

A telephoto zoom lens according to claim 1, wherein the following numerical data are provided: ______________________________________ Focal distance f: 204 to 588, F-number: 5.7 to 8.0 Field Angle: 12.0° to 4.2° ______________________________________ r d Abbe n ______________________________________ 1 553.910 4.00 45.9 1.54814 2 -1179.705 0.20 3 108.444 3.00 25.5 1.80458 4 75.675 11.00 82.5 1.49782 5 1809.705 (variable) 6 -191.100 2.50 52.3 1.74810 7 64.006 4.00 8 70.449 6.00 27.8 1.69911 9 316.273 (variable) 10 -906.473 5.00 82.5 1.49782 11 -90.369 (variable) 12 96.107 7.50 70.4 1.48749 13 -73.565 2.00 28.6 1.79504 14 -172.530 (variable) 15 461.565 3.50 25.5 1.73038 16 -52.207 1.40 17 -51.990 2.00 39.8 1.86994 18 67.671 (Bf) ______________________________________ f 204.0165 400.0025 588.0043 ______________________________________ d5 2.8635 56.5702 80.2283 d9 99.7316 38.6171 9.4726 d11 1.4970 45.9439 78.8618 d14 66.6878 37.2231 6.6014 Bf 85.2559 114.7210 145.3431 ds 96.5316 35.4171 6.2726 ______________________________________ where r denotes curvature radius of the lens, d denotes the thickness of the lens and the interval between lens surfaces, n denotes the refraction rate, the Abbe's number and the refraction rate n are the values with respect to line d, symbol ds denotes the distance from the apex of the lens surface of said second lens group which is most adjacent to said image to the diaphragm.

Claim 15

A telephoto zoom lens according to claim 1, wherein the following numerical data are provided: ______________________________________ Focal distance f: 204 to 585, F-number: 5.7 Field Angle: 12.0° to 4.2° ______________________________________ r d Abbe n ______________________________________ 1 747.377 6.00 45.9 1.54814 2 -1473.962 0.20 3 129.752 4.00 25.5 1.80458 4 90.902 17.60 82.5 1.49782 5 -4432.360 (variable) 6 -171.026 3.60 52.3 1.74810 7 74.655 4.10 8 80.571 7.00 27.8 1.69911 9 440.540 (variable) 10 -989.301 7.00 82.5 1.49782 11 -98.573 (variable) 12 108.265 7.50 70.4 1.48749 13 -82.425 3.00 28.6 1.79504 14 -189.936 (variable) 15 711.702 4.50 25.5 1.80458 16 -77.649 4.00 40.9 1.79631 17 71.724 (Bf) ______________________________________ f 204.0103 400.0025 585.0035 ______________________________________ d5 9.3357 68.1754 93.4110 d9 101.8839 43.0442 17.8086 d11 1.1095 50.1426 85.1848 d14 75.1643 38.5559 3.2212 Bf 83.3343 119.9431 155.2781 ds 73.6643 37.0559 1.7213 ______________________________________ where r denotes curvature radius of the lens, d denotes the thickness of the lens and the interval between lens surfaces, n denotes the refraction rate, the Abbe's number and the refraction rate n are the values with respect to line d, symbol ds denotes the distance from the apex of the lens surface of the fourth lens group which is most adjacent to the image of the diaphragm.

Claim 16

A telephoto zoom lens comprising, in the order from an object side: a first lens group having positive refracting power; a second lens group having negative refracting power; a third lens group having positive refracting power; a fourth lens group having positive refracting power; a fifth lens group having negative refracting power, said fifth lens group being moved toward the object at the time of the zooming operation performed from the wide angle end to the telephoto end in order to reduce the positive distortion generated at the telephoto end, wherein, when magnification is varied from the wide angle end to telephoto end, an air interval between said first lens group and said second lens group is enlarged, an air interval between said second lens group and said third lens group is reduced, an air interval between said third lens group and aid fourth lens group is enlarged and an air interval between said fourth lens group and said fifth lens group is reduced.

Claim 17

A telephoto zoom lens comprising, in the order from an object side: a first lens group having positive refracting power; a second lens group having negative refracting power; a third lens group having positive refracting power; a fourth lens group having positive refracting power; a fifth lens group having negative refracting power, said fifth lens group being moved toward the object at the time of the zooming operation performed from the wide angle end to the telephoto end in order to reduce the positive distortion generated at the telephoto end, wherein, when magnification is varied from the wide angle end to telephoto end, an air interval between said first lens group and said second lens group is enlarged, an air interval between said second lens group and said third lens group is reduced, an air interval between said third lens group and aid fourth lens group is enlarged and an air interval between said fourth lens group and said fifth lens group is reduced.

Claim 18

A telephoto zoom lens according to claim 15, wherein aid third lens group consists of a positive meniscus lens convex to the image side.

Claim 19

A telephoto zoom lens according to claim 16, wherein said positive meniscus lens of said third lens group satisfies the following condition, where the curvature radius of the lens surface of said positive lens adjacent to an object is r a and the curvature radius of the lens surface adjacent to said image is r b ##EQU14##

Claim 20

A telephoto zoom lens comprising, in the order from an object side: a first lens group having positive refracting power; a second lens group having negative refracting power; a third lens group having positive refracting power; a fourth lens group having positive refracting power; a fifth lens group having negative refracting power, wherein, when magnification is varied from the wide angle end to the telephoto end, an air interval between said first lens group and said second lens group is enlarged, an air interval between said second lens group and said third lens group is reduced, an air interval between said third lens group and said fourth lens group is enlarged and an air interval between said fourth lens group and said fifth lens group is reduced, and wherein, at the telephoto end, said second lens group and said third lens group from an intermediate negative lens group G M to compensate the spherical aberration, and said fourth lens group and said fifth lens group form a rearward negative lens group G R to compensate off-axis aberration.

Claim 21

A telephoto zoom lens comprising, in the order from an object side: a first lens group having positive refracting power; a second lens group having negative refracting power; a third lens group having positive refracting power; a fourth lens group having positive refracting power; a fifth lens group having negative refracting power, wherein, when magnification is varied from the wide angle end to the telephoto end, an air interval between said first lens group and said second lens group is enlarged, an air interval between said second lens group and said third lens group is reduced, an air interval between said third lens group and said fourth lens group is enlarged and an air interval between said fourth lens group and said fifth lens group is reduced, and wherein, at the telephoto end, said second lens group and said third lens group from an intermediate negative lens group G M to compensate the spherical aberration, and said fourth lens group and said fifth lens group form a rearward negative lens group G R to compensate off-axis aberration.

Claim 22

A telephoto zoom lens according to claim 18, wherein said fifth lens group is moved toward the object at the time of the zooming operation performed from the wide angle and to the telephoto end in order to reduce the positive distortion generated at the telephoto end.