| 摘要 |
PURPOSE:To view the transmission of the apply voltage as a moving picture by performing the predetermined phase shift of a beam every time when (n) of vertical scanning signals are produced during the scanning of a specimen on which a synchronized pulse beam of an electron beam is applied. CONSTITUTION:The electron beam from an electron gun 2 provided in a mirror tube 1 is deflected by a pulse beam generating deflector 6 to be controlled by a pulse width control circuit 15 and a pulse beam is produced by an aperture board 7. Said beam will pass through a focus lens 3 then deflected 5X, 5Y by the signal from a scan signal generating circuit 14, to irradiate a specimen 4. The secondary electron emitted from the specimen 4 on which the synchronous voltage is applied from a signal generator 10 is detected 16. A pulse oscillator 8 is connected to a phase control circuit and said circuit 10. In such a device when three vertical scan signals are provided from the circuit 14, a counter 11 is set to provided single signal to the circuit 9 thus to display the specimen image having the phase phi, 2phi, 3phi as a moving picture on a cathode ray tube 12. |
