| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens whose entire lens system is compact, and which has excellent optical performance for a close object at the telephoto end.SOLUTION: The zoom lens includes, in order from the object side to the image side: a first lens group having a negative refractive power; a second lens group having a positive refractive power; and a third lens group having a positive refractive power. The second lens group has a second-a lens group having a positive refractive power and a second-b lens group having a positive refractive power. When zooming, the distances between adjacent lens groups are changed. At least in a part of a zoom range, focusing operation with respect to a close object is performed by advancing the second-b lens group and the third lens group by a predetermined amount. The imaging magnification &bgr;2bT of the second-b lens group at the telephoto end, and the imaging magnification &bgr;3T of the third lens group at the telephoto end are appropriately set, respectively. |
