| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact large-diameter photographic lens having high performance.SOLUTION: A photographic lens comprises, in order from an object side: a positive first lens group G1; an aperture diaphragm S; a positive second lens group G2; and a negative third group lens G3. The first group lens comprises two lenses of a positive lens with a convex surface facing the object side and a negative lens with a concave surface facing an image side. The second lens group comprises three lenses of a cemented lens of a negative lens with a concave surface facing the object side and a positive lens with a convex surface facing the image side and a positive lens with a convex surface facing the object side. The third lens group comprises two lenses of a positive lens with a convex surface facing the image side and a negative lens with a concave surface facing the object side. The photographic lens satisfies conditions of (1) 0.0<(Y'/F).(D23/TL)<0.1 and (2) 0.4<Y'/F<1.2, where Y' is an image height, F is the focal length of the entire system, D23 is a distance on an optical axis from the surface closest to the image side of the second lens group to the surface closest to the object side of the third lens group, when focusing on infinity, and TL is a distance on the optical axis from the lens surface closest to the object side to an image surface, when focusing on infinity. |
