Patent ID: 7230775

Claim:
An electronic imaging system comprising a taking lens and an electronic image pickup device located on an image side thereof, wherein: the taking lens comprises a front lens group consisting of a negative lens component and a positive lens component and having positive refracting power and a rear lens group consisting of, in order from an object side thereof, a negative lens element and a positive lens element and having positive refracting power, with an aperture stop interposed between the front lens group and the rear lens group, and conditions (1) and (2) are satisfied: 2.8 <f B /IH <4.5 (1) 2<SF<3 (2) where f B is a length, as calculated on an air basis, of a back focus of the taking lens, IH is a length that is half a diagonal length of an effective plane of the electronic image pickup device, and SF is a shape factor (R F +R R )/(R F −R R ) for the negative lens component in the front lens group where R F and R R are radii of curvature of the object side and image side of the negative lens component in the front lens group, respectively.