A camera which drives a focusing lens to a target position in a short
period of time while maintaining required stop accuracy in accordance with
the status of an image-taking optical system, is disclosed. The camera
comprises the image-taking optical system and a pulse generator that
outputs pulse signals in accordance with movement of the focusing lens. A
stop judging unit selectively carries out, in accordance with the status
of the image-taking optical system, a first stop judgement of the focusing
lens by detecting that the count value of pulse signals has reached a
target count value, and a second stop judgement of the focusing lens by
detecting that the output signal from the pulse generator does not change.
