Patent ID: 7511893
Filing Date: 2009-03-31
Classification: G02B

Abstract:
1. A zoom lens system in sequence arranging from an object side toward an image side comprising: a first lens group with a negative optical power, comprising in sequence from an object side to an image side, a first negative lens, a first positive lens, and a second negative lens made of plastic; a second lens group with a positive optical power comprising, in sequence from an object side to an image side, a second positive lens, a third negative lens adhered to the second positive lens, and a third meniscus positive lens; and a third lens group with a positive optical power, comprising a fourth positive lens; wherein the zoom lens system meets a criteria of where R1 indicates a curvature radius facing the object side of a first surface of the second negative lens; and R2 indicates a curvature radius facing the image side of a second surface of the second negative lens.