| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens capable of obtaining higher image quality, an imaging apparatus, and a method for varying a focal length of the zoom lens. SOLUTION: The zoom lens includes, in order from an object: a first lens group G1 having negative refractive power; a second lens group G1 having positive refractive power; a third lens group G3 having negative refractive power; and a fourth lens group G4 having positive refractive power. Upon zooming from a wide-angle end state to a telephoto end state, each lens group moves along an optical axis such that a distance between the first and the second lens groups G1 and G2 decreases, a distance between the second and the third lens groups G2 and G3 increases, and the distance between the third and the fourth lens groups G3 and G4 decreases; and the first lens group G1 includes a negative lens, at least one lens in the negative lens includes an aspherical surface, and the negative lens of the first lens group G1 satisfies prescribed conditionals. COPYRIGHT: (C)2008,JPO&INPIT
|
