Zoom lens and image pickup apparatus having the same
AssigneeCanon Kabushiki Kaisha
InventorShigenobu Sugita
Life of this patent
Estimating the term…
Abstract
A zoom lens includes an aperture stop and a plurality of lens units which are moved during zooming. The plurality of lens units includes, on an object side of the aperture stop, a lens unit Lp having a positive refractive power and a lens unit Ln having a negative refractive power which is disposed to be adjacent to an image side of the positive lens unit Lp. At least one of the positive lens unit Lp and the negative lens unit Ln includes two or less lenses which are moved during focusing, and a focal length Fp of the positive lens unit Lp and a focal length Fn of the negative lens unit Ln are appropriately set based on predetermined mathematical conditions.
Claims23
A zoom lens comprising:
- an aperture stop;
- and
- a plurality of lens units which are moved during zooming,
- wherein the plurality of lens units includes, on an object side of the aperture stop, a positive lens unit Lp having a positive refractive power and a negative lens unit Ln having a negative refractive power which is disposed to be adjacent to an image side of the positive lens unit Lp,
- wherein at least one of the positive lens unit Lp and the negative lens unit Ln includes two or less lenses which are moved during focusing, and
- wherein a composite focal length of lens units disposed on the image side of the negative lens unit Ln at a wide-angle end is positive, and a composite focal length of lens units disposed on the object side of the positive lens unit Lp at the wide-angle end is negative,
- wherein, when focal lengths of the positive and negative lens units Lp and Ln are respectively denoted by Fp and Fn, and a lateral magnification of the negative lens unit Ln at a wide-angle end is denoted by βnw, the following conditions are satisfied:
- 0.5<|Fp/Fn|<2.0,
- |βnw|<1.0.
An optical apparatus comprising:
- a zoom lens;
- an aperture stop;
- a plurality of lens units which are moved during zooming;
- and
- an image sensor configured to receive an image formed by the zoom lens,
- wherein the plurality of lens units includes, on an object side of the aperture stop, a positive lens unit Lp having a positive refractive power and a negative lens unit Ln having a negative refractive power which is disposed to be adjacent to an image side of the positive lens unit Lp,
- wherein at least one of the positive lens unit Lp and the negative lens unit Ln includes two or less lenses which are moved during focusing,
- wherein a composite focal length of lens units disposed on the image side of the negative lens unit Ln at a wide-angle end is positive, and a composite focal length of lens units disposed on the object side of the positive lens unit Lp at the wide-angle end is negative, and
- wherein, when focal lengths of the positive and negative lens units Lp and Ln are respectively denoted by Fp and Fn, a lateral magnification of the negative lens unit Ln at a wide-angle end is denoted by βnw, the following conditions are satisfied:
- 0.5<|Fp/Fn|<2.0, and
- |βnw|<1.0.
A zoom lens comprising:
- an aperture stop;
- and
- a plurality of lens units which are moved during zooming,
- wherein the plurality of lens units includes, on an object side of the aperture stop, a positive lens unit Lp having a positive refractive power and a negative lens unit Ln having a negative refractive power which is disposed to be adjacent to an image side of the positive lens unit Lp,
- wherein at least one of the positive lens unit Lp and the negative lens unit Ln includes two or less lenses which are moved during focusing,
- wherein a composite focal length of lens units disposed on the image side of the negative lens unit Ln at a wide-angle end is positive, and a composite focal length of lens units disposed on the object side of the positive lens unit Lp at the wide-angle end is negative, and
- wherein, when focal lengths of the positive and negative lens units Lp and Ln are respectively denoted by Fp and Fn, the following condition is satisfied:
- 0.938≦|Fp/Fn|<2.0.
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, a third lens unit having a positive refractive power, a fourth lens unit having a negative refractive power, a fifth lens unit having a positive refractive power, and a sixth lens unit having a positive refractive power, wherein each lens unit is moved during zooming, the zoom lens comprising:
- an aperture stop on the image side of the fourth lens unit,
- wherein at least one of the third lens unit and the fourth lens unit includes two or less lenses which are moved during focusing, and
- wherein, when focal lengths of the third and fourth lens units are respectively denoted by Fp and Fn, the following condition is satisfied:
- 0.5<|Fp/Fn|<2.0.
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, a third lens unit having a positive refractive power, a fourth lens unit having a negative refractive power, and a fifth lens unit having a positive refractive power, wherein each lens unit is moved during zooming, the zoom lens comprising:
- an aperture stop on the image side of the fourth lens unit,
- wherein at least one of the third lens unit and the fourth lens unit includes two or less lenses which are moved during focusing, and
- wherein, when focal lengths of the third and fourth lens units are respectively denoted by Fp and Fn, the following condition is satisfied:
- 0.5<|Fp/Fn|<2.0.
A zoom lens including, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, a third lens unit having a negative refractive power, a fourth lens unit having a positive refractive power, and a fifth lens unit having a positive refractive power, wherein each lens unit is moved during zooming, the zoom lens comprising:
- an aperture stop on the image side of the third lens unit,
- wherein at least one of the second lens unit and the third lens unit includes two or less lenses which are moved during focusing, and
- wherein, when focal lengths of the second and the third lens units are respectively denoted by Fp and Fn, the following condition is satisfied:
- 0.5<|Fp/Fn|<2.0.
Dependencies are inferred from the claim text.