Patent ID: 9335528
Filing Date: 2016-05-10
CPC Classification: G02B

Claim Text:
1. A zoom lens comprising, in order from an object side to an image side, a first lens unit having positive refractive power, a second lens unit having negative refractive power, a third lens unit having positive refractive power, a fourth lens unit having negative refractive power, and a fifth lens unit having positive refractive power, wherein at least the first lens unit, the second lens unit, and the third lens unit move during zooming so that the first lens unit is located closer to an object side, the second lens unit is located closer to an image side, and the third lens unit is located closer to the object side at a telephoto end than a wide-angle end, wherein the following conditional expressions are satisfied: where Tdw is an overall lens length at the wide-angle end, M1 is the amount of movement of the first lens unit during zooming from the wide-angle end toward the telephoto end, M2 is the amount of movement of the second lens unit during zooming from the wide-angle end toward the telephoto end, f1 is the focal length of the first lens unit, fw is the focal length of the entire lens at the wide-angle end, and ft is the focal length of the entire lens at the telephoto end; and the sign of the amounts of movement of the lens units is positive when the lens units are moved to be located closer to the object side at the telephoto end than the wide-angle end, and is negative when the lens units are moved to be located closer to the image side at the telephoto end than the image side.