| 摘要 |
PURPOSE:To control a high brightness object according to a picture angle and to allow a small-sized circuit to appropriately prevent a malfunction due to the high brightness object by varying the size of a split small picture angle for control in accordance with the size of a picture angle for extracting a video signal and attaining the same splitting number. CONSTITUTION:An automatic focussing device is provided with a circuit extracting a video signal at an optional picture angle, and a memory device 16 which splits the picture angle into plural parts and can cope with the split picture angles, and its function is to vary the size of the split picture angle depending upon a change in an extraction picture angle. Namely a selection circuit 17, deciding the size of the picture angle to be extracted, decides the extracted picture angle. According to said angle the timing for accessing a memory device group 16 horizontally and vertically is modified. Position information on the picture angle of a high brightness part is stored in the memory device 16, and based on the information the picture angle that should be extracted by a gate circuit is controlled so as not to extract the high brightness object part. Therefore only by an appropriate video signal the automatic focussing can be attained. |
