| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens whose aberration is satisfactorily corrected, which has such a wide viewing angle that a half viewing angle is≥38°, and whose f-number at a short focus end is≤2.5 though it is very compact, and to provide a camera device and a personal digital assistant. SOLUTION: The zoom lens has a first lens group G1 having a positive focal distance, a second lens group G2 having a negative focal distance, a third lens group G3 having a positive focal distance, and a fourth lens group G4 having a positive focal distance in order from an object side, and has a diaphragm on the object side of the third lens group G3. When varying power from the short focus end to a long focus end, a distance between the first lens group G1 and the second lens group G2 is increased, a distance between the second lens group G2 and the third lens group G3 is decreased, and a distance between the third lens group G3 and the fourth lens group G4 is increased. The third lens group G3 has a cemented lens comprising a positive lens, a negative lens and a positive lens, and besides at least one or more lenses in order from the object side. COPYRIGHT: (C)2007,JPO&INPIT
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