| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens which has a high zoom ratio of ≥about 10, which has a viewing angle where a half viewing angle is ≥38° at a wide angle end, which has less aberration, and which has resolution corresponding to an imaging device having more than 5 to 10 million pixels. SOLUTION: The zoom lens includes in order from an object side: a positive first positive lens group G1; a negative second lens group G2; a positive third lens group G3; and a positive fourth lens group G4. Upon varying the power from a wide angle end to a telephoto 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 second lens group G2 includes in order from the object side: a negative lens E4; a positive lens E5; and a negative lens E6. The zoom lens satisfies inequalities (1): 0.50<f1/ft<0.80 and (2): νd1ave>47, wherein f1 denotes a focal length of the first lens group G1, ft denotes a focal length of the whole system at the telephoto end, νd1ave denotes an average Abbe number of the first lens group G1. COPYRIGHT: (C)2010,JPO&INPIT |
