| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact zoom lens suitable for a photographing lens and a video camera lens or the like and having a variable power ratio being abut 4.5, and optical equipment using the zoom lens. SOLUTION: This zoom lens is provided with a 1st lens group having negative refractive power, a 2nd lens group having positive refractive power, a 3rd lens group having positive refractive power, and a 4th lens group having negative refractive power from an object side. In the case of variable power, the respective lens groups are moved on an optical axis at a telephoto end with respect to a wide-angle end so that a distance between the 1st lens group and the 2nd lens group may be long, a distance between the 2nd lens group and the 3rd lens group may be long and a distance between the 3rd lens group and the 4th lens group may be short. Then, the focal distance Fw of an entire system at the wide-angle end, the focal distance Fi of an i-th lens group, and the synthetic focal distance F12w of the 1st lens group and the 2nd lens group at the wide-angle end are appropriately set, respectively.
|
