Wide angle zoom lens
AssigneePanavision International, L.P.
InventorTakanori Yamanashi
Life of this patent
Estimating the term…
Abstract
Embodiments of a zoom lens system may comprise at least four lens groups having a NPNP power sequence. The first lens group may include a stationary lens element. The second through fourth lens groups may be movable during zooming. An additional movable N or P lens group on the image side of the system may correct field curvatures or astigmatism. The first lens group may include a stationary, N first lens subgroup and an N second lens subgroup having a movable lens element for focusing. The first lens group may contribute to low focus breathing. Multiple lens groups may have matching movement plans. Some embodiments may be high speed and have a first lens group that can be stationary during zoom. Some embodiments may have only one aspheric surface.
Claims15
A zoom lens system for forming an image of an object, said system having an object side and an image side, said system having a wide position and a tele position for zooming, said system comprising in order from the object side to the image side:
- a first lens group with negative power and having a stationary lens element;
- a second lens group with positive power;
- a third lens group with negative power;
- a fourth lens group with positive power;
- and
- a fifth lens group;
- wherein the second, third, fourth, and fifth lens groups are movable to vary magnification of the image during zooming,
- the second and fourth lens groups moving toward the object side during zooming from the wide position to the tele position, and
- the fifth lens group moving toward the image side and then toward the object side during zooming from the wide position to the tele position.
A zoom lens system for forming an image of an object, said system having an object side and an image side, said system comprising in order from the object side to the image side:
- a first lens group with negative power, the first lens group including:
- a first lens subgroup with negative power and being stationary and
- a second lens subgroup with negative power and including a lens element being movable to vary focus of the image;
- a second lens group with positive power;
- a third lens group with negative power;
- a fourth lens group with positive power;
- and
- wherein the second, third, and fourth lens groups are movable to vary magnification of the image during zooming.
A zoom lens system for forming an image of an object, said system having an object side and an image side, said system having a wide position and a tele position for zooming, said system comprising in order from the object side to the image side:
- a first lens group with negative power, the first lens group including:
- a first lens subgroup with negative power and being stationary and
- a second lens subgroup with negative power and including a lens element being movable to vary focus of the image;
- a second lens group with positive power;
- a third lens group with negative power;
- a fourth lens group with positive power;
- and
- a fifth lens group;
- wherein the second, third, fourth, and fifth lens groups are movable to vary magnification of the image during zooming,
- the second and fourth lens groups moving toward the object side during zooming from the wide position to the tele position, and
- the fifth lens group moving toward the image side and then toward the object side during zooming from the wide position to the tele position.
Dependencies are inferred from the claim text.