Back to results
US 7,253,961 B2Granted
Zoom lens system and image pickup apparatus including the same
AssigneeCanon Kabushiki Kaisha
InventorNobuyuki Miyazawa
Life of this patent
Estimating the term…
Abstract
At least one exemplary embodiment is directed to a zoom lens system which includes, in order from an object side to an image side, a first lens unit with positive optical power, a second lens unit with negative optical power, a third lens unit with positive optical power, a fourth lens unit with positive or negative optical power, and a fifth lens unit with positive optical power. In at least one exemplary embodiment of this zoom lens system, during zooming, the second lens unit, the third lens unit, and the fifth lens unit can move along the optical axis.
Claims20
A zoom lens system comprising, in order from an object side to an image side:
- a first lens unit with positive optical power;
- a second lens unit with negative optical power, the second lens unit moving along an optical axis during zooming;
- a third lens unit with positive optical power, the third lens unit moving along the optical axis during zooming;
- a fourth lens unit;
- a fifth lens unit with positive optical power, the fifth lens unit moving along the optical axis during zooming,
- wherein a distance between the first lens unit and the second lens unit, a distance between the second lens unit and the third lens unit, a distance between the third lens unit and the fourth lens unit, and a distance between the fourth lens unit and the fifth lens unit vary during zooming;
- and
- an aperture stop disposed at the object side with respect to the fourth lens unit,
- wherein the aperture stop does not move for zooming.
6 more elements
A zoom lens system comprising, in order from an object side to an image side:
- a first lens unit with positive optical power;
- a second lens unit with negative optical power, the second lens unit moving along an optical axis during zooming;
- a third lens unit with positive optical power, the third lens unit moving along the optical axis during zooming;
- a fourth lens unit;
- and
- a fifth lens unit with positive optical power, the fifth lens unit moving along the optical axis during zooming,
- wherein a distance between the first lens unit and the second lens unit, a distance between the second lens unit and the third lens unit, a distance between the third lens unit and the fourth lens unit, and a distance between the fourth lens unit and the fifth lens unit vary during zooming and wherein the fifth lens unit moves during focusing.
4 more elements
A zoom lens system comprising, in order from an object side to an image side:
- a first lens unit with positive optical power;
- a second lens unit with negative optical power, the second lens unit moving along an optical axis during zooming;
- a third lens unit with positive optical power, the third lens unit moving along the optical axis during zooming;
- a fourth lens unit;
- and
- a fifth lens unit with positive optical power, the fifth lens unit moving along the optical axis during zooming,
- wherein a distance between the first lens unit and the second lens unit, a distance between the second lens unit and the third lens unit, a distance between the third lens unit and the fourth lens unit, and a distance between the fourth lens unit and the fifth lens unit vary during zooming wherein the third lens unit moves along the optical axis so as to exhibit a locus convex toward the object side during zooming from a wide-angle end to a telephoto end, and
- the following condition is satisfied:
- 0.3<D2m/D2t<0.6
- where D2m is the amount of movement of the second lens unit when the second lens unit moves from the wide-angle end to a zoom position Za, the zoom position Za is a zoom position when the third lens unit is disposed nearest to the object side during the zooming, and D2t is the amount of movement of the second lens unit when the second lens unit moves from the wide-angle end to the telephoto end.
7 more elements
A zoom lens system comprising, in order from an object side to an image side:
- a first lens unit with positive optical power;
- a second lens unit with negative optical power, the second lens unit moving along an optical axis during zooming;
- a third lens unit with positive optical power, the third lens unit moving along the optical axis during zooming;
- a fourth lens unit;
- and
- a fifth lens unit with positive optical power, the fifth lens unit moving along the optical axis during zooming,
- wherein a distance between the first lens unit and the second lens unit, a distance between the second lens unit and the third lens unit, a distance between the third lens unit and the fourth lens unit, and a distance between the fourth lens unit and the fifth lens unit vary during zooming wherein the following condition is satisfied:
- 1.0<(B13w−B2)/D2t<1.2
- where B13w is the distance between the first lens unit and the third lens unit at the wide-angle end, B2 is the distance between an object-side surface of the second lens unit and an image-side surface of the second lens unit, the object-side surface being nearest to the object side and the image-side surface being nearest to the image side in the second lens unit, and D2t is the amount of movement of the second lens unit when the second lens unit moves from the wide-angle end to the telephoto end.
6 more elements
Dependencies are inferred from the claim text.