ZOOM LENS AND IMAGING OPTICAL DEVICE HAVING THE SAME

摘要

PURPOSE: A zoom lens and an imaging optical device having the same are provided to photograph an object in the wider range by realizing super wide angle and large aperture. CONSTITUTION: A first lens group(G1) has the positive refractive power. A second lens group(G2) has the negative refractive power. A third lens group(G3) has the positive refractive power. A fourth lens group(G4) has the positive refractive power. The first optic group comprises a joined lens of a positive lens(2) and a negative lens(1).