Zoom lens and image pickup apparatus
AssigneeCanon Kabushiki Kaisha
InventorMakoto Nakahara
Life of this patent
Estimating the term…
Abstract
Provided is a zoom lens including, in order from an object side to an image side: a first lens unit having a positive refractive power; a second lens unit having a negative refractive power; and a third lens unit having a positive refractive power, in which an interval between each pair of adjacent lens units is changed during zooming, the first lens unit consists of, in order from the object side to the image side, a positive lens and a negative lens, and a focal length of the first lens unit, a focal length of the third lens unit, a focal length of the negative lens, and a focal length of an entire system of the zoom lens at a wide-angle end are each appropriately set.
Claims16
A zoom lens comprising, in order from an object side to an image side:
- a first lens unit having a positive refractive power;
- a second lens unit having a negative refractive power;
- and
- a third lens unit having a positive refractive power,
- wherein an interval between each pair of adjacent lens units is changed during zooming,
- wherein the first lens unit consists of a positive lens and a negative lens arranged on the image side of the positive lens,
- wherein the following conditional expressions are satisfied:
- 5.0<f1/f3<12.0;
- and
- −14.0<fG2/fw<−3.0,
- where f1 represents a focal length of the first lens unit, f3 represents a focal length of the third lens unit, fG2 represents a focal length of the negative lens, and fw represents a focal length of an entire system of the zoom lens at a wide-angle end.
An image pickup apparatus comprising:
- a zoom lens;
- and
- an image pickup element configured to receive an image formed by the zoom lens,
- the zoom lens including, in order from an object side to an image side:
- a first lens unit having a positive refractive power;
- a second lens unit having a negative refractive power;
- and
- a third lens unit having a positive refractive power,
- wherein an interval between each pair of adjacent lens units is changed during zooming,
- wherein the first lens unit consists of a positive lens and a negative lens arranged on the image side of the positive lens,
- wherein the following conditional expressions are satisfied:
- 5.0<f1/f3<12.0;
- and
- −14.0<fG2/fw<−3.0,
- where f1 represents a focal length of the first lens unit, f3 represents a focal length of the third lens unit, fG2 represents a focal length of the negative lens, and fw represents a focal length of an entire system of the zoom lens at a wide-angle end.
Dependencies are inferred from the claim text.