| 摘要 |
PURPOSE:To obtain two functions by one device, by constituting a digital subtraction system by using a quickly rising image pickup tube to realize an afterimage effect at the time of through-vision mode by using the frame memory. CONSTITUTION:When a through-vision mode is selected, a switching circuit 22 is switched so that a video signal, which does not pass a logarithmic conversion circuit 21, is stored in frame memories 25 and 26 by every one frame, which is successively obtained, through an AD conversion circuit 23 and arithmetic processing circuit 24. The arithmetic processing circuit 24 adds video signals, which are continuously obtained at real time, of one frame before and two frames before for each picture element. When this integrated signals are displayed, a through-vision picture integrated by every three frames at real time is shown. Therefore, so-called a picture image having a large afterimage effect is obtained. |
