Optical device with inherent focusing error correction

摘要

In an imaging apparatus, provided is an optical device which is capable of changing the magnifying power thereof. The optical device includes a zoom lens system having a power varying lens group and a correction lens group both of which are movable in the direction of the optical axis of the zoom lens system with respect to the zoom lens system. The zoom lens system is moved in the direction of the optical axis of the zoom lens system, and the power varying lens is driven synchronously with the movement of the zoom lens system. Further, the zoom lens system and the correction lens are moved in accordance with a magnifying power and data representing the amount of the displacement of the zoom lens system respective to the optical axis and the displacement of the correction lens with respect to the optical system.