| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical system which offers a wide view angle and high optical performance.SOLUTION: An optical system comprises, in order from the object side to the image side, a front group LF having negative refractive power, an aperture stop SP, and a rear group LR having positive refractive power, where the front group LF has a meniscus-shaped negative lens g1 located on the most object side. A focal length fw of the entire system, a focal length fg1 of the negative lens g1, a curvature radius R2 of an image-side surface of the negative lens g1 satisfy the following conditional expressions: 3.0<|fg1/fw|<6.1, and 1.9<R2/fw<3.0. |
