Patent ID: 6710934
Filing Date: 2004-03-23
Classification: G02B

Abstract:
A compact zoom lens system, the lens system when viewed from an object side, comprising:a first lens group of a negative refractive power, the first lens group comprising at least one lens of a negative refractive power and at least one lens of a positive refractive power; a second lens group of a positive refractive power, the second lens group comprising a first lens of a positive refractive power, a second lens of a positive refractive power, and a third lens of a negative refractive power; and a third lens group of a positive refractive power, the third lens group comprising at least a lens of a positive refractive power; wherein the first, the second, and the third lens groups move along an optical axis, and the zoom lens system satisfies the following conditions: 0.4&leq;tIIfW&it;fT&leq;0.6&it;â€ƒ&it;and&it;â€ƒ&it;2.8&leq;fTfW&leq;3.0;andwhereinfW represents a total focal length at a wide-angle position, fT represents a total focal length at a telephoto position, and IIrepresents a total thickness of the second lens group.