| 摘要 |
PURPOSE:To improve the operation efficiency of an electron microscope and achieve its stable condition in a short time by automatically operating a means for producing and accelerating electron rays, a means for deflecting them and a lens system for converging electron rays and forming an image after a hard vacuum is produced by detecting the vacuum degree of the mirror tube. CONSTITUTION:Within the mirror tube 27 of an electron microscope, electron rays 28 are converged and deflected before being irradiated upon a sample 5 and then electron rays passing through the sample 5 are magnified by an image formation lens system 6 to project an image upon a fluorescent plate 7. The vacuum degree of the mirror tube 27 is detected with a detector 8 and a vacuum meter 20 and a signal produced when a given vacuum degree is achieved is sent into a micro processor 23. The signal from the processor 23 and data read from (ROM24) and (RAM25) are passed through read-out DA converters 17, 18 and 19 respectively before being used to apply acceleration voltage and to excite a lens coil and a deflection coil. In addition, data for cancelling the starting drift are used to achieve a shift to a stable condition. Therefore, the electron microscope can be automatically used only by turning on an operation switch for the exhaust system, thereby facilitating handling of the electron microscope. |
