Patent ID: 9188770
Filing Date: 2015-11-17
Classification: G02B

Abstract:
1. A zoom lens consisting of, in order from the object side: a first lens unit having a positive refractive power; a second lens unit having a negative refractive power; a third lens unit having a positive refractive power; a fourth lens unit having a negative refractive power; and a fifth lens unit having a positive refractive power, wherein the first lens unit and the fifth lens unit move during zooming from the wide angle end to the telephoto end, and the following conditional expressions (1), (2), and (3) are satisfied: where f t is the focal length of the entire zoom lens system at the telephoto end, f w is the focal length of the entire zoom lens system at the wide angle end, Fno( T ) is the F-number of the entire zoom lens system at the telephoto end, and Σd is the sum of the thicknesses of the first to fifth lens units, where the thickness of each lens unit refers to the distance on the optical axis from the lens surface closest to the object side to the lens surface closest to the image side in each lens unit.