| 摘要 |
PROBLEM TO BE SOLVED: To provide a comparatively small wide angle lens having a long back focal distance capable of inserting a various kinds of optical members and high optical performance by composing the lens with a front group and a rear group composed of specified lens groups, respectively, and satisfying a specified condition. SOLUTION: This wide angle lens is composed of plural lens groups, a front group closest to the object side has a negative refractive power as a whole, is composed of a first group of a positive lens and a second group of two negative lenses. The rear group closest to the image side has a positive refractive power as a whole, is composed of a first lens group of a positive lens, a second lens group of a negative lens and a third lens group of a positive lens. The conditions: 0.10<|f/fF|<1.00, 2.00|e/f|<9.00, 0.20<|f/fR|<1.20, 0.20<|f/fF-2|<0.90 are satisfied, where, fF, fR: the focal distances of the front group and the rear group, respectively, e: the interval between principal points of the front group and the rear group, fF-2 : the focal distance of the second lens group of front group and f: the focal distance of the whole lens system.
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