| 摘要 |
PROBLEM TO BE SOLVED: To provide a variable power optical system capable allowing more correction of various aberrations such as spherical face aberration, color aberration, and astigmatism than those of background technologies despite a compact design, and to provide an imaging apparatus and a digital device. SOLUTION: The variable power optical system 1 includes, in order from the object side to the image side, a first lens group 11 with negative optical power, a second lens group 12 with positive optical power, and a third lens group 13 with negative optical power. For varying power from the wide angle end to the telephoto end, the first lens group 11 and second lens group 12 move so as to decrease a distance between them. When power varies, the first lens group 11 is fixed in position. In the second lens group 12, a lens closest to the object has positive optical power, and at least one negative lens is included. The third lens group 13 has at least one positive lens and at least one negative lens. The second lens group 12 and third lens group 13 each have at least one aspherical face. If the imaging magnifications of the third lens group 13 at the telephoto end and the wide-angle end are represented byβ3t andβ3w, the variable power optical system satisfiesβ3t/β3w>1.5. COPYRIGHT: (C)2009,JPO&INPIT
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