| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a zoom lens achieving a high magnification zoom ratio and a wide viewing angle while having a superior imaging quality. <P>SOLUTION: The wide-angle zoom lens includes, in order from a photographing object side towards an imaging side, a first lens group 10 having a positive refractive power, a second lens group 20 having a negative refractive power, a third lens group 30 having a positive refractive power, and a fourth lens group 40 having a positive refractive power. All of the first lens group 10, the second lens group 20, the third lens group 30 and the fourth lens group 40 are installed movably along an optical axis, and satisfy the following conditional expression: 1.6<f3/fw<2.1, where f3 represents an effective focal length of the third lens group, and fw represents an effective focal length of the wide-angle zoom lens in a wide angle state. <P>COPYRIGHT: (C)2012,JPO&INPIT |
