| 摘要 |
PROBLEM TO BE SOLVED: To provide a sighting telescope capable of focusing in a short distance of several meters by a slight movement of a focusing lens. SOLUTION: The sighting telescope comprises an objective lens, an erecting lens, and an ocular lens. The objective lens comprises a positive first lens group and a second lens group for focusing while moving. The second lens group for focusing is an objective lens including a convex lens group and a concave lens group. By moving only the convex lens group or the concave lens group out of the second lens group in the optical axis direction at the focusing, focus adjustment is achieved to a short distance with a dramatically small moving amount. COPYRIGHT: (C)2010,JPO&INPIT
|
