Patent ID: 9268119
Filing Date: 2016-02-23
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 a negative refractive power, a second lens unit having a positive refractive power, and a third lens unit having a positive refractive power, the lens units being configured to change intervals between the respective neighboring lens units for zooming, the zoom lens having an F-number which is constant over an entire zoom range, the zoom lens comprising a first variable stop and a second variable stop, the first variable stop being disposed between the first lens unit and the second lens unit and having an aperture diameter changing for zooming, the second variable stop being disposed in an image side of the first variable stop and having an aperture diameter changing for zooming, wherein the following conditional expressions are satisfied: where Sw1 represents a distance from the first variable stop to an image plane at a wide-angle end, Sw2 represents a distance from the second variable stop to the image plane at the wide-angle end, and Tkw represents a distance from an exit pupil position to the image plane at the wide-angle end.