Patent ID: 6084722
Filing Date: 2000-07-04
Classification: G02B

Abstract:
A zoom lens of rear focus type, comprising, in order from an object side to an image side:a first lens unit of positive refractive power;a second lens unit of negative refractive power, said second lens unit moving toward the image side during zooming from a wide-angle end to a telephoto end;a third lens unit of positive refractive power; anda fourth lens unit of positive refractive power, at least a part of said fourth lens unit moving to compensate for an image shift caused by the zooming and moving to effect focusing,wherein said second lens unit comprises, in order from the object side to the image side, a first lens of negative refractive power, a second lens of negative refractive power, a third lens of negative refractive power, and a fourth lens of positive refractive power.