Patent ID: 6844987
Filing Date: 2005-01-18
Classification: G02B

Abstract:
1. A zoom lens system comprising, in order from an object side, a first lens group having a positive refracting power and a second lens group having a negative refracting power, magnification being changed from a wide-angle end to a telephoto end by moving the first and second lens groups toward the object side and by reducing an interval between the first and second lens groups, said first lens group comprising, in order from the object side: a first lens having a negative refracting power, a concave surface of said first lens being directed to the object side; a second lens having a positive refracting power; a third lens having a negative refracting power; and a fourth lens having a positive refracting power, wherein said zoom lens system satisfies the following conditions: where fs denotes a focal length of the zoom lens system at the wide-angle end, f