| 摘要 |
PURPOSE:To obtain a simple secured synthetic image by supplying a plural kinds of video signals so that they are electronically switched for each scanning line and used as the input to the fluorescent screen of a CRT, and visually synthesizing the video signals into the CRT screen. CONSTITUTION:A reflected electron 5 traveling from the surface of a sample 4 is detected with a detector 7a. Following that, the detected signal is amplified with an amplifier 8a, treated with a signal-treating circuit 9a, and made into an image signal. On the other hand, a secondary electron 6 discharged from a sample 4 is detected with a detector 7b, and the detected signal is made into an image signal by passing through an amplifier 8b and being treated with a signal-treating circuit 9b. The outputs of the circuits 9a and 9b, image signals, are switched alternately through a switching circuit 12, and used as the input to a CRT13. A photographing singal circuit 14 is made to drive a photographing device 15 which photographs the image of the CRT13. The device 15 is made to provide a photograph which is obtained by synthesizing images of the CRT13 which are obtained through the circuits 9a and 9b. |
