| 摘要 |
PROBLEM TO BE SOLVED: To provide an imaging optical system which includes a wide angle of view, that is, a half angle of view of 38°or more, a large aperture of F2.0 or less, high performance even at a near distance and can be made compact. SOLUTION: The imaging optical system includes a first group I having positive or negative power, an aperture diaphragm S, and a second group II having positive power, which are disposed in order from an object side. In focusing from infinity to a near distance object, the first group I is moved to an image side and the second group II is moved to the object side. COPYRIGHT: (C)2010,JPO&INPIT |
