| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens that is sufficiently small, while a high quality image and a wide view angle, which has a half-view angle of 42°or larger, are obtained and an F number of 3.0 or smaller at a short focal end is available, and to provide a camera device and a personal digital assistant. SOLUTION: The zoom lens includes 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 having a positive focal distance, in this order starting from the object side, and a diaphragm on the object side of the third lens group G3. When magnification varies from the short focal end to a long focal end, the interval between the first lens group G1 and second lens group G2 increases, the interval between the second lens group G2 and the third lens group G3 decreases, and the interval between the third lens group g3 and the fourth lens group G4 changes; the third lens group G3 has a positive first lens L6, a negative second lens L7, a positive third lens L8, and a negative fourth lens L9, in this order starting from the object side; and the object-side face of the positive first lens L6 and the object-side face of the second lens L7 are convex surfaces oriented toward the object direction. COPYRIGHT: (C)2008,JPO&INPIT
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