| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens system which offers increased magnification in a range of approximately 28x to 30x, good short distance performance throughout a zoom range from the short focal length end to the long focal length end, and a reduced size (total length).SOLUTION: A zoom lens system includes a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, a fourth lens group having negative refractive power, and a fifth lens group having positive refractive power arranged in order from the object side. When zooming from the short focal length end to the long focal length end, the distance between the first lens group and the second lens group is widened while the distance between the second lens group and the third lens group is narrowed. At least in part of an entire zoom range, both the fourth lens group and the fifth lens group move when focusing acting as a focusing lens group. |
