Patent ID: 6483648
Filing Date: 2002-11-19
Classification: G02B

Abstract:
A zoom lens system comprising, in order from an object of the zoom lens system, a first lens group having positive refracting power, a second lens group having negative refracting power, a third lens group having positive refracting power, a fourth lens group having negative refracting power and a fifth lens group having positive refracting power, wherein:for zooming from a wide-angle end to a telephoto end of said zoom lens system, a spacing between said first lens group and said second lens group and a spacing between said third lens group and said fourth lens group becomes wider and a spacing between said second lens group and said third lens group and a spacing between said fourth lens group and said fifth lens group becomes narrower, and the following conditions are satisfied: 4.5464&lE;f1/fw<8.0â€ƒâ€ƒ(1) 0.42/fw|<1.0â€ƒâ€ƒ(2) 0.33/fT345<1.2â€ƒâ€ƒ(3) 0.64|/fT345<5.0â€ƒâ€ƒ(4) 0.55/fT345<4.0â€ƒâ€ƒ(5) where fw is a focal length of said zoom lens system at said wide-angle end, f1 is a focal length of said first lens group, f2 is a focal length of said second lens group, f3 is a focal length of said third lens group, f4 is a focal length of said fourth lens group, f5 is a focal length of said fifth lens group, and fT345 is a focal length of said third lens group to said fifth lens group at said telephoto end.