| 摘要 |
PROBLEM TO BE SOLVED: To overcome the problem that a focusing time cannot be sufficiently shortened because the stop position precision of a focusing lens is uniformly determined by a severe stop precision required on the telephoto side. SOLUTION: A camera system is provided with a photographic optical system including a focusing lens 2, driving means 13 and 14 for driving the focusing lens to a target position, a pulse generation means 17 for outputting a pulse signal in accordance with movement of the focusing lens, and a stop decision means 10 which decides it on the basis of the pulse signal from the pulse generation means that the focusing lens has stopped in the target position, and the stop decision means is made to selectively perform first stop decision that stop of the focusing lens in the target position is decided by arrival of a pulse counted value from the pulse generation means at a counted value corresponding to the target position and second stop decision that stop of the focusing lens in the target position is decided by changelessness in an output signal from the pulse generation means for a prescribed time or longer, in accordance with the state of the photographic optical system. COPYRIGHT: (C)2004,JPO |
