Patent ID: 7193651

Claim:
A camera system comprising: a camera comprising an image pickup device to pick up an optical image, a first storage circuit for storing information about the image pickup device, and a first communication unit; and a lens apparatus removably mounted on the camera and adapted to form an optical image on the image pickup device, the lens apparatus comprising a focus lens, a second storage circuit for storing a plurality of driving characteristics of the focus lens, and a second communication unit which can communicate with the first communication unit; and a controller selecting one of the plurality of driving characteristics stored in the second storage circuit and driving the focus lens using the selected driving characteristics, wherein the controller selects the driving characteristics in accordance with the information which is stored in the first storage circuit and sent to the controller from the camera through the first and the second communication unit, and wherein the information stored in the first storage circuit is selected from the group consisting of image pickup area size, number of pixels, pixel size, and diameter of a permissible circle of confusion on the image pickup surface of the image pickup device.