Rear converter optical system and imaging apparatus including the same
AssigneeCanon Kabushiki Kaisha
InventorSatoshi Maetaki
Life of this patent
Estimating the term…
Abstract
Provided is a rear converter optical system which is detachably mounted on an image side of a main lens system to increase a focal length of the main lens system, in which an effective diameter Φim of an imaging area of the main lens system, an effective diameter Φcr of a lens surface closest to the image side of the rear converter optical system, a lateral magnification βc of the rear converter optical system in the case where the rear converter optical system is mounted on the main lens system, a backfocus skc in the case where the rear converter optical system is mounted on the main lens system are appropriately set.
Claims14
A rear converter optical system which is detachably mounted on an image side of a main lens system to increase a focal length of the main lens system, wherein following conditional expressions are satisfied:
- 0.58≤Φcr/(Φim×βc)<1.0;
- and
- 0.8<(Φcr/2+0.35×skc)/(Φim×βc/2)<1.5,
- where Φim represents a diameter of an image circle of the main lens system, Φcr represents an effective diameter, which is a diameter of a region through which light rays imaged by the main lens system and the rear converter optical system pass, of a lens surface closest to the image side of the rear converter optical system, βc represents a lateral magnification of the rear converter optical system in the case where the rear converter optical system is mounted on the main lens system, and skc represents a backfocus in the case where the rear converter optical system is mounted on the main lens system.
A rear converter optical system which is detachably mounted on an image side of a main lens system to expand an imaging area of the main lens system,
- wherein following conditional expressions are satisfied:
- 0.8<Φcr/Ymax<2.0;
- and
- 0.9<(Φcr/2+0.35×skc)/Ymax<1.3,
- where 2Ymax represents a diameter of an image circle in the case where the rear converter optical system is mounted on the main lens system, Φcr represents an effective diameter, which is a diameter of a region through which light rays imaged by the main lens system and the rear converter optical system pass, of a lens surface closest to the image side of the rear converter optical system, and skc represents a backfocus in the case where the rear converter optical system is mounted on the main lens system.
A rear converter optical system which is detachably mounted on an image side of a main lens system to increase a focal length of the main lens system, wherein following conditional expressions are satisfied:
- 0.4<Φcr/(Φim×βc)<1.0;
- 0.8<(Φcr/2+0.35×skc)/(Φim×βc/2)<1.5;
- and
- 1.4<Φic/Φim<2.0,
- where Φim represents an effective diameter of an imaging area of the main lens system, Φcr represents an effective diameter of a lens surface closest to the image side of the rear converter optical system, βc represents a lateral magnification of the rear converter optical system in the case where the rear converter optical system is mounted on the main lens system, skc represents a backfocus in the case where the rear converter optical system is mounted on the main lens system, and Φic represents an effective diameter of an imaging area in the case where the rear converter optical system is mounted on the main lens system.
A rear converter optical system which is detachably mounted on an image side of a main lens system to expand an imaging area of the main lens system, wherein following conditional expressions are satisfied:
- 0.8<Φcr/Ymax<2.0;
- 0.8<(Φcr/2+0.35×skc)/Ymax<1.5;
- and
- 1.4<Φic/Φim<2.0,
- where 2Ymax represents an effective diameter of an imaging area in the case where the rear converter optical system is mounted on the main lens system, Φcr represents an effective diameter of a lens surface closest to the image side of the rear converter optical system, skc represents a backfocus in the case where the rear converter optical system is mounted on the main lens system, Φim represents the effective diameter of the imaging area of the main lens system and Φic represents an effective diameter of an imaging area in the case where the rear converter optical system is mounted on the main lens system.
Dependencies are inferred from the claim text.