ZOOM LENS SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a zoom lens system optimal for a collapsible camera having a variable power ratio of about 10 times, an angle of view of 70 degrees or more at a short focal length end, a small front lens size and a short lens total length of the short focal length end. SOLUTION: The zoom lens system comprises, from an object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group having a positive refractive power. In variable magnification from the short focal length end to a long focal length end, the first to fourth lens groups are moved in an optical axis direction so that at least the second lens group is moved to an image side with a convex moving trajectory toward the image side, and the fourth lens group is moved temporality to the object side, and then to the image side so as to satisfy following conditional formula (1): 3