| 摘要 |
PURPOSE:To continue a focusing control even at the fluctuating time of an object image by detecting the change of the object image due to a panning, etc., with an object image change detecting means and limitting the passing frequency band of an image-pick up signal to the extent of the change. CONSTITUTION:To obtain the high frequency signals of two types for a down- hill control, two high-pass filters (HPF) 14A and 14B, whose low frequency band cut-off frequencies are different, are provided and by changing-over switches 26 and 28 with the output of an object image change detecting circuit 30, the high frequency signal of a different band is impressed to a detecting circuit 16. In the case fo the HPF 14A of which the low frequency band cut-off frequency is high, a steep characteristic is obtained and in the case of the HPF 14B in which the low frequency band cut-off frequency is low, a gentle characteristic is obtained. When the object is moved, a camera is panned or the photographed object is changed by a hand-shaking, the down-hill control can be continued even at the fluctuating time of the object image by selecting the HPF 14B. |
