| 摘要 |
PURPOSE:To increase the range of the use and improve the automatic reaquisition performance after losing of the target, by providing plural edge gates, which function independently of one another, at upper, lower, left, and right edges of the target on a screen and by detecting edge signals to track always the center point of the target. CONSTITUTION:The video signal obtained by image pickup machine 1 is supplied to horizontal edge detecting circuit 2 and vertical edge detecting circuit 3. In horizontal edge detecting circuit 2, left and right edge signals of the target are detected by left edge detecting circuit 21 and right edge detecting circuit 22 and are supplied to horizontal error signal generating circuit 23, and horizontal shift is detected and is output to control part 4. Meanwhile, in vertical edge detecting circuit 3, upper and lower edge signals of the target are detected by upper edge detecting circuit 31 and lower edge detecting circuit 32 and are supplied to vertical error signal generating circuit 33, and vertical shift is detected and is output to control part 4. Control part 4 controls horizontal and vertical directions of image pickup machine 1 according to these signals. |
