ZOOM LENS AND INFORMATION DEVICE

摘要

PROBLEM TO BE SOLVED: To obtain a zoom lens whose half-viewing angle at a wide-angle end is 38°or larger, whose variable power ratio is 4.5 or larger, and which is compact and has resolving power coping with an imaging device having 4,000,000 to 8,000,000 pixels or more. SOLUTION: The zoom lens has a first lens group I having positive refractive power, a second lens group II having negative refractive power, a third lens group III having positive refractive power and a fourth lens group IV having positive refractive power in order from an object side, where the first lens group I moves to the object side, when power is varied from the wide angle end to a telephoto end. The fourth lens group IV is constituted of one positive lens, and both surfaces of the positive lens are aspherical. The total moving amount of the first lens group I, when the power is varied from the wide-angle end to the telephoto end: where X1 is the focal distance of the entire system at the telephoto end: and fT satisfy the condition: (1) 0.30