| 摘要 |
PROBLEM TO BE SOLVED: To provide a lightweight, large-diameter telephoto lens that increases spacing between first and second lenses while maintaining satisfactory optical performance and that has a simple configuration. SOLUTION: The lens includes, in order from an object side, a first lens group L1 with positive refractive power, a second lens group L2 with negative refractive power, and a third lens group L3 with positive refractive power. When the lens focuses on a close-distance object from the infinity distance of an object, the second lens group L2 moves from the object side to the image surface side on an optical axis. The lens satisfies prescribed conditional expressions. COPYRIGHT: (C)2011,JPO&INPIT
|
