Patent ID: 9696525
Date: 2017-07-04
CPC Classifications: G02B,H04N

Claim:
1. A zoom lens, comprising: 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; and a fourth lens unit having a positive refractive power, the first through fourth lens units being arranged in order from an object side to an image side, wherein a distance between adjacent lens units changes when zooming, wherein, when zooming, the first lens unit is stationary, wherein, when zooming from a wide angle end to a telephoto end, the second lens unit is configured to move toward the image side and then to move toward the object side, and the third lens unit is configured to move monotonously toward the object side, wherein the second lens unit includes two or more negative lenses, and wherein, when a focal length of the second lens unit is represented by f2, a focal length of the third lens unit is represented by f3, and a focal length of the zoom lens at the wide angle end is represented by fw, conditional expressions −1.05<f2/f3<−0.30 and −5.00<f2/fw<−2.50 are satisfied.