| 摘要 |
PROBLEM TO BE SOLVED: To provide a novel inner focus type telephoto lens that enables an excellent correction of a chromatic aberration.SOLUTION: An inner focus type telephoto lens comprises; a positive first lens group I; a negative second lens group II; a positive third lens group III, arranged in order from an object side to an image side,; and an aperture stop S between the first lens group and the second lens group, in which the second lens group II moves on an optical axis to thereby implement focusing. The first lens group includes, arranged in order from the object side to the image side: a positive lens; a positive lens; a positive lens; a negative lens; a negative lens; and a positive lens. A sixth lens is in proximity to or bonded to a fifth lens. When a conjugate point on the object side is at infinity, a focal length of the first lens group, a focal length of the second lens group, an Abbe number of a material of the fifth lens and an Abbe number of a material of the sixth lens satisfy appropriately set conditions.SELECTED DRAWING: Figure 1 |
