| 摘要 |
This wide angle lens is formed of, in order from the object side to the image side, the following: a first lens group having a positive refractive power; an aperture stop; a second lens group having a negative refractive power; and a third lens group having a positive refractive power. When subject distance changes from infinity to a proximity distance, focusing is performed as a result of the second lens group being moved towards the image side. The first lens group includes: a negative lens which is disposed closest to the object side, and a convex surface of which faces the object side; and at least one cemented lens. The first lens group satisfies conditional formula (1): 0.5<f1/f<1.0. f1: focal length of the first lens group when focusing to infinity. f: focal length of the entire system when focusing to infinity. |
