Lens device and shooting system
AssigneeCanon Kabushiki Kaisha
InventorShinichiro Yakita
Life of this patent
Estimating the term…
Abstract
A lens device having a function of varying a magnification of the lens device and a function of focusing includes, in the order from an object side to an image side, a first lens unit which has a positive optical power and which is fixed during the variation of magnification, a second lens unit which has a negative optical power and which moves during the variation of magnification, and a third lens unit which has a positive optical power and which is fixed during the variation of magnification. The third lens unit includes a first lens sub-unit which is fixed during focusing, a second lens sub-unit which has a positive optical power and which moves during focusing, and a third lens sub-unit which has a positive optical power and which is fixed during focusing, in that order from the object side to the image side.
Claims8
A lens device having a function of varying a magnification of the lens device and a function of focusing, comprising, in the order from an object side to an image side:
- a first lens unit which has a positive optical power and which is fixed during the variation of magnification;
- a second lens unit which has a negative optical power and which moves during the variation of magnification;
- and
- a third lens unit which has a positive optical power and which is fixed during the variation of magnification,
- wherein the third lens unit includes a first lens sub-unit which is fixed during focusing, a second lens sub-unit which has a positive optical power and which moves during focusing, and a third lens sub-unit which has a positive optical power and which is fixed during focusing, in that order from the object side to the image side.
Dependencies are inferred from the claim text.