Patent ID: 6744468
Filing Date: 2004-06-01
Classification: G02B,H04N

Abstract:
A lens control device comprising:(A) a first lens movable for varying power; (B) a second lens for compensating for a change in position of a focal position due to the movement of the first lens; (C) a memory which stores information about a plurality of loci of the second lens to keep focused state during the movement of the first lens; (D) a third lens mounted in an optical axis of the first and second lenses in a detachable manner; and (E) control means for changing a movable range of the first lens from a first range to a second range in response to the mounting of the third lens to restrict the movable range of the first lens such that the second lens is able to move and compensate the change of the focal position due to the movement of the first lens in the second range in response to the movement of the first lens from the first range to the second range, wherein said control means, when the first lens is moved from the first range to the second range, controls the second lens to move according to the locus on which the second lens has been tracing during the first lens has positioned within the first range.