| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact zoom lens having high optical performance all over the variable power range, consisting of two lens groups between which the lens group having negative refractive power precedes, having the short entire length of a lens and including the wide angle of view. SOLUTION: This zoom lens is provided with a front group having negative refractive power and a rear group having positive refractive power in order from an object side, and performs variable power by changing a distance between the front group and the rear group. The front group is provided with an Fa group having positive refractive power and an Fb group having negative refractive power in order from the object side, and the Fa group and the Fb group are moved so that a distance between the Fa group and the Fb group may be changed at the time of variable power. The rear group is provided with an Ra group having positive refractive power and an Rb group having positive refractive power in this order from the object side, and the Ra group and the Rb group are moved so that a distance between the Ra group and the Rb group may be changed at the time of the variable power. At the time of performing the variable power from a wide-angle end to a telephoto end, the moving directions of the Fa group and the Rb group are reversed with respect to the image surface of the lens entire system.
|
