| US 7,515,194 B2 | ||
| Image pickup optical system and optical apparatus using the same | ||
| Tetsuo Nagata, Hachioji (Japan); Tomoko Sato, Hachioji (Japan); Akihiro Sakurai, Hino (Japan); Tetsuya Ishii, Hachioji (Japan); Takeshi Takahashi, Hachioji (Japan); and Kazuhiro Matsumoto, Hachioji (Japan) | ||
| Assigned to Olympus Corporation, Tokyo (Japan) | ||
| Filed on Jul. 30, 2004, as Appl. No. 10/902,302. | ||
| Claims priority of application No. 2003-284162 (JP), filed on Jul. 31, 2003; and application No. 2004-007900 (JP), filed on Jan. 15, 2004. | ||
| Prior Publication US 2005/0046952 A1, Mar. 03, 2005 | ||
| Int. Cl. G02B 13/16 (2006.01); H04N 5/225 (2006.01) | ||
| U.S. Cl. 348—335 [348/337; 348/338; 359/720; 359/726; 359/728; 359/831; 359/833; 359/856] | 17 Claims |
| 1. An image pickup optical system comprising, in order from an object side:
a front unit having at least one reflecting surface with power that is rotationally asymmetrical;
an aperture stop; and
a rear unit having at least one reflecting surface with power that is rotationally asymmetrical,
wherein F-numbers in two directions perpendicular to each other on a plane perpendicular to an optical axis are different,
to satisfy the following condition:
1.1<FNY/FNX<2.0
where FNY is the F-number in a decentering direction and FNX is the F-number in a direction perpendicular to the decentering
direction.
|