Zoom lens with high optical performance and image pickup apparatus having the same

摘要

A zoom lens comprises a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a rear group including at least two lens units and having a positive refractive power as a whole, in order from an object side to an image side. An interval of each of the lens units changes in a zoom operation, the rear group includes a lens unit R having a positive refractive power at the most image side, the lens unit R includes a lens having a concave surface at the image side and having an aspherical surface shape where a negative refractive power becomes stronger with increasing distance from an optical axis, and focal lengths f1, fR, and fw of the first lens unit, the lens unit R, and a whole system at a wide-angle end, respectively, are appropriately set.

主权项

1. A zoom lens comprising:
a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a rear group including at least two lens units and having a positive refractive power as a whole in an entire zoom range, in order from an object side to an image side, wherein an interval of each of the lens units is configured to change in a zoom operation, the rear group includes a lens unit R having a positive refractive power at the most image side of the rear group, the lens unit R includes a lens having a concave surface at the image side and the concave surface having an aspherical surface shape where a negative refractive power becomes stronger with increasing distance from an optical axis, and the following conditional expressions are satisfied,
4.4