Patent ID: 7099089

Claim:
A control apparatus controlling a zoom lens including, in order from an object side, a first lens unit which moves for varying the magnification, a light amount adjusting unit which adjusts a light amount, and a second lens unit which moves for focusing, the control apparatus comprising: a memory which stores in-focus position data of the second lens unit with respect to a position of the first lens unit; and a controller which controls a position of the second lens unit with respect to a position of the first lens unit based on the in-focus position data, wherein the controller sets a reference position of the second lens unit for position control of the second lens unit with the in-focus position data based on a difference between an in-focus position of the second lens unit for an object at anywhere from a minimum object distance to an infinite distance when the first lens unit is located at a wide-angle end and an in-focus position of the second lens unit for the object when the first lens unit is located at a predetermined focal length position other than the wide-angle end, and the zoom lens satisfies the following condition: 2 εF/|s|≦|Mw| where ε represents a permissible circle of confusion of the camera, F represents a full F number when the first lens unit is located at a wide-angle end, s represents amount of displacement of an image-forming position in the optical axis direction during movement of the second lens unit by a predetermined amount, and Mw represents a difference between in-focus positions of the second lens unit for an object at the infinite distance and for an object at the minimum distance, when the first lens unit is located at the wide-angle end.