| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens which has a large diameter although it is compact and exhibits excellent optical performance over the whole zooming range.SOLUTION: There is provided a zoom lens including in order from an object side to an image side, a first lens group having negative refractive power, a second lens group having positive refractive power, a third lens group having negative refractive power, and a fourth lens group having positive refractive power. In zooming from a wide-angle end to a telescopic end, the first lens group moves to the object side in such a manner that a distance with the second lens group narrows, a distance between the third lens group and the fourth lens group widens, and the fourth lens group is fixed. The second lens group includes four lenses of a first positive lens, a second positive lens, a negative lens and a third positive lens, in order from the object side, and the second positive lens and the negative lens are joined with each other. |
