Patent ID: 8873156
Filing Date: 2014-10-28
Classification: G02B

Abstract:
1. A zoom lens comprising, in order from a magnification conjugate side, a first lens unit that has a positive refractive power and is fixed during magnification variations, and a magnification-variable unit configured to move for magnification variations, wherein the first lens unit includes, in order from the magnification conjugate side, a first lens sub-unit that has a positive refractive power and is configured to move during focusing, and a second lens sub-unit that has a positive refractive power and is configured to move during focusing, wherein the first lens sub-unit and the second lens sub-unit are configured to move and reduce an interval between the first lens sub-unit and the second lens sub-unit for focusing from infinity to a close end, and wherein a surface of the second lens sub-unit closest to the magnification conjugate side has a concave shape on the magnification conjugate side.