Patent ID: 8279532
Filing Date: 2012-10-02
Classification: G02B

Abstract:
1. A zoom lens system comprising a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive refractive power; the first, second, and third lens groups being arranged sequentially from an object side; when the zoom lens system is zoomed from a wide angle position to a telephoto position, an interval between the first lens group and the second lens group decreases and an interval between the second lens group and the third lens group increases; the first lens group comprising a first lens, a second lens, and a third lens arranged sequentially from the object side; and the zoom lens system satisfying the following expression: wherein fw indicates a focal length of the zoom lens system at the wide angle position, ft indicates a focal length of the zoom lens system at the telephoto position, and N2 indicates a refractive index of the second lens of the first lens group.