Patent ID: 8878911

Claim:
A three-dimensional image pickup optical system for forming two different images having a parallax for left and right eyes alternately in time sequence on a single image pickup element, the three-dimensional image pickup optical system comprising, in order from an object side: a front optical system including a pair of 1f-lens units each having a negative refractive power, a pair of optical path deflecting units, and an optical path combining unit for combining two optical paths on the same optical axis; and a rear optical system including a 1b-lens unit having a positive refractive power which does not move for magnification-varying, a lens unit which moves for the magnification-varying, and a stop, wherein the front optical system includes a pair of light quantity control units, which are disposed in the optical paths for the left and right eyes on the object side of the optical path combining unit, for switching left and right subject images alternately in a time sharing manner, and wherein the following conditions are satisfied: −10.0 <f 1 f/fw<− 1.5; and 0.9 <f 1 b/ft< 5.0, where f1f denotes a focal length of the 1f-lens unit, f1b denotes a focal length of the 1b-lens unit, fw denotes a focal length at a wide angle end of the three-dimensional image pickup optical system, and ft denotes a focal length at a telephoto end of the three-dimensional image pickup optical system.