Zoom lens

A zoom lens comprising a front diverging lens group and a rear converging leng group which are mechanically movable for variable power, said front diverging lens comprising a first lens of negative meniscus which is convex toward on object, a second negative lens, and a third lens of positive meniscus which is convex toward the object, said rear converging lens comprising a fourth positive lens, a fifth positive lens, a sixth negative lens, and a seventh positive lens, there being an aperture disposed more closely than said rear group to the object and movable with said rear group, said zoom lens satisfying the following conditions:

• ##EQU3## where f.sub.T :
• the combined focal length of the entire lens system at a maximum focal length,
• f.sub.I :
• the combined focal length of the front group,
• f.sub.II :
• the combined focal length of the rear group,
• f1, 2:
• the combined focal length from the first to the second lens,
• f1, f2, f3, f6:
• the focal lengths of the first third, and sixth lenses,
• n1, n2:
• the refractive indexes of the first and second lenses with respect to d-line, and
• l2:
• the air gap between the second and third lenses,
• e:
• the distance between a principal point of the front group closer to the image and a principal point of the rear group closer to the object at a maximum focal length, and wherein
• ______________________________________ F = 36-68.5 F number 1:4.1 Angle of view 2.omega. = 64.4.degree.-34.6.degree. ri di n .nu. ______________________________________ 1 103.259 1.980 1.74400 44.7 2 27.613 4.316 3 61.861 1.880 1.74950 35.3 4 30.868 2.886 5 29.874 5.415 1.76182 26.6 6 72.468 39.031-4.243 7 39.784 3.505 1.72000 50.3 8 -131.754 0.100 9 21.700 5.038 1.66892 45.0 10 238.059 0.589 11 -193.355 6.040 1.80518 25.4 12 16.599 6.228 13 -217.297 2.239 1.58144 40.8 14 -33.020 ##STR25## ##STR26## ##STR27## ##STR28## ##STR29## ##STR30## ______________________________________

A zoom lens comprising a front diverging lens group and a rear converging leng group which are mechanically movable for variable power, said front diverging lens comprising a first lens of negative meniscus which is convex toward an object, a second negative lens, and a third lens of positive meniscus which is convex toward the object, said rear converging lens comprising a fourth positive lens, a fifth positive lens, a sixth negative lens, and a seventh positive lens, there being an aperture disposed more closely than said rear group to the object and movable with said rear group, said zoom lens satisfying the following conditions:

• ##EQU4## where f.sub.T :
• the combined focal length of the entire lens system at a maximum focal length,
• f.sub.I :
• the combined focal length of the front group,
• f.sub.II :
• the combined focal length of the rear group,
• f1, 2:
• the combined focal length from the first to the second lens,
• f1, f2, f3, f6:
• the focal lengths of the first, second, third, and sixth lenses,
• n1, n2:
• the refractive indexes of the first and second lenses with respect to d-line,
• l2:
• the air gap between the second and third lenses, and
• e:
• the distance between a principal point of the front group closer to the image and a principal point of the rear group closer to the object at a maximum focal length, and wherein
• ______________________________________ F = 36-68.5 F number 1:4.1 Angle of view 2.omega. = 64.5.degree.-34.7.degree. ri di n .nu. ______________________________________ 1 93.720 1.980 1.83400 37.2 2 28.700 4.240 3 69.120 1.880 1.80610 40.9 4 33.150 2.950 5 31.885 5.370 1.80518 25.4 6 89.072 41.111-3.821 7 39.600 3.500 1.74400 44.7 8 -132.321 0.100 9 21.200 4.040 1.65844 50.9 10 193.485 0.640 11 -206.849 6.040 1.80518 25.4 12 16.570 6.700 13 -92.459 2.230 1.58144 40.8 14 -28.475 ##STR31## ##STR32## ##STR33## ##STR34## ##STR35## ##STR36## ______________________________________