Zoom lens and image pickup apparatus
AssigneeCanon Kabushiki Kaisha
InventorTakashi Okada
Life of this patent
Estimating the term…
Abstract
Provided is a zoom lens including: a positive first unit; a negative second unit; a positive third unit; a positive fourth unit; a positive fifth unit; and a sixth unit, wherein the first unit is moved toward the object side for zooming from wide angle end to telephoto end, and an interval between each pair of adjacent units is changed for zooming, wherein the fifth unit is moved for focusing, and wherein a focal length at wide angle end, a focal length of the fifth unit, an F-number of the zoom lens at wide angle end, a total length at wide angle end, a distance from a lens surface on the object side of the fifth unit to an image plane at wide angle end at infinity, and a movement amount of the fifth unit for zooming from wide angle end to telephoto end at infinity are appropriately set.
Claims13
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;
- a third lens unit having a positive refractive power;
- a fourth lens unit having a positive refractive power;
- a fifth lens unit having a positive refractive power;
- and
- a sixth lens unit,
- wherein the first lens unit is configured to move toward the object side for zooming from a wide angle end to a telephoto end, and an interval between each pair of adjacent lens units is changed for zooming,
- wherein the fifth lens unit is configured to move for focusing, and
- wherein the following conditional expressions are satisfied:
- 2.0<f5/fw<10.0;
- 0.1<Fnow×D5iw/Lw<0.8;
- and
- 0.05<M5/Lw<0.30,
- where fw represents a focal length of the zoom lens at the wide angle end, f5 represents a focal length of the fifth lens unit, Fnow represents an F-number of the zoom lens at the wide angle end, Lw represents a total length of the zoom lens at the wide angle end, D5iw represents a distance from a lens surface on the object side of the fifth lens unit to an image plane at the wide angle end when the zoom lens is focused at infinity, and M5 represents a movement amount of the fifth lens unit for zooming from the wide angle end to the telephoto end when the zoom lens is focused at infinity.
An image pickup apparatus comprising:
- a zoom lens;
- and
- an image pickup element configured to receive an image formed by the zoom lens,
- wherein 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;
- a third lens unit having a positive refractive power;
- a fourth lens unit having a positive refractive power;
- a fifth lens unit having a positive refractive power;
- and
- a sixth lens unit,
- wherein the first lens unit is configured to move toward the object side for zooming from a wide angle end to a telephoto end, and an interval between each pair of adjacent lens units is changed for zooming,
- wherein the fifth lens unit is configured to move for focusing, and
- wherein the following conditional expressions are satisfied:
- 2.0<f5/fw<10.0;
- 0.1<Fnow*D5iw/Lw<0.8;
- and
- 0.05<M5/Lw<0.30,
- where “fw” represents a focal length of the zoom lens at the wide angle end, f5 represents a focal length of the fifth lens unit, Fnow represents an F-number of the zoom lens at the wide angle end, Lw represents a total length of the zoom lens at the wide angle end, D5iw represents a distance from a lens surface on the object side of the fifth lens unit to an image plane at the wide angle end when the zoom lens is focused at infinity, and M5 represents a movement amount of the fifth lens unit for zooming from the wide angle end to the telephoto end when the zoom lens is focused at infinity.
Dependencies are inferred from the claim text.