Patent ID: 6339508
Filing Date: 2002-01-15
Classification: G02B

Abstract:
A photographic optical system comprising in order from the object side: a front lens unit which comprises at least a negative lens element and has negative refractive power as a whole; and a rear lens unit which comprises at least two positive lens elements and at least a negative lens element, and has positive refractive power as a whole, wherein a reflecting member to fold an optical path and an aperture stop are disposed in order from the object side between said front lens unit and said rear lens unit, and wherein said photographic optical system satisfies the following conditions (1) and (2):1.5F|/f<3.5â€ƒâ€ƒ(1) 1.6<dM/f<2.6â€ƒâ€ƒ(2) wherein the reference symbol f represents a focal length of said optical system as a whole, the reference symbol fF designates a focal length of said front lens unit and the reference symbol dM denotes an optical path length on an optical axis from a final surface of said front lens unit to said aperture stop.