PROBLEM TO BE SOLVED: To provide a high variable power zoom lens system having a variable power ratio of 15 times or over, having a viewing angle of 70 degrees or more at a short focal distance end, having a front lens whose diameter is small and having a short lens entire length at the short focal distance end, and optimum for a collapsible camera.;SOLUTION: The high variable power zoom lens system includes in order from an object side: a first lens group having positive refractive power; a second lens group having negative refractive power; a third lens group having positive refractive power; and a fourth lens group having positive refractive power. In varying power, at least one of the first lens group and the third lens group moves in the optical axis direction so that the distance between the first lens group and the second lens group increases, the distance between the second lens group and the third lens group decreases, and the distance between the third lens group and the fourth lens group increases; and the moving amount of the first lens group is larger than the moving amount of the third lens group. The first lens group is constituted of three lenses - a negative lens, a positive lens, and a positive lens - in order from the object side and, in the first lens group, the absolute value of curvature radius of the object side face of the negative lens is smaller than the absolute value of curvature radius of the object side face of the positive lens on the object side, and 1.95n11 is satisfied (n11: the refractive index of the negative lens in the first lens group).;COPYRIGHT: (C)2012,JPO&INPIT
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