Zoom lens and image pickup apparatus having the same

Patent metadata

Field	Value
Publication number	US-8958007-B2
Application number	US-201313942341-A
Country	US
Kind code	B2
Filing date	Jul 15, 2013
Priority date	Jul 18, 2012
Publication date	Feb 17, 2015
Grant date	Feb 17, 2015

Abstract

A zoom lens includes a first lens unit having negative refractive power, a second lens unit having positive refractive power, a third lens unit having negative refractive power, and a fourth lens unit having positive refractive power, in order from an object side to an image side, each lens unit moving during zooming, and the third lens unit moving toward the object side during focusing from an infinitely-distant object to a nearby object. A focal length f 3 of the third lens unit, a composite focal length f 12 t of the first lens unit and the second lens unit at a telephoto end, a focal length fw of the entire system at a wide-angle end, and a focal length ft of the entire system at the telephoto end are appropriately set.

First claim

What is claimed is:

1. A zoom lens comprising, in order from an object side to an image side:
a first lens unit having negative refractive power;
a second lens unit having positive refractive power;
a third lens unit having negative refractive power; and
a fourth lens unit having positive refractive power,
wherein each lens unit moves during zooming,
wherein the third lens unit moves toward the object side during focusing from an infinitely-distant object to a nearby obj…

Assignees

• Canon Kk

Inventors

• Nishimura Takeshi

Classifications

• H04N23/67

  Electricity · mapped topic

• G02B15/177 Primary

  Physics · mapped topic

• H04N5/23212

  Electricity · mapped topic

• G02B27/646

  Physics · mapped topic

• G02B15/14 Primary

  Physics · mapped topic