Patent ID: 6606194
Filing Date: 2003-08-12
Classification: G02B

Abstract:
A variable magnification optical system having an image stabilizing function, comprising, in order from an object side, a fixed first lens unit of positive refractive power, a second lens unit of negative refractive power, a third lens unit of positive refractive power and a fourth lens unit of positive refractive power, said second lens unit and said fourth lens unit being moved along an optical axis to effect variation of magnification, wherein said third lens unit comprises a first lens sub-unit of negative refractive power and a second lens sub-unit of positive refractive power, and said second lens sub-unit is made to move in a direction perpendicular to the optical axis to stabilize an image, said variable magnification optical system satisfying the following conditions:83/fw<25 0.332/f3|<0.75 where f3 is a focal length of said third lens unit, fw is a focal length in a wide-angle end of the entire optical system, and f32 is a focal length of said second lens sub-unit.