| 摘要 |
PURPOSE:To both perform a nondestructive inspection and observation for a large structural body and obtain an easy enlargement of its field of vision, by arranging a mirror body frame and its placing mount for shifting the field of vision on a sample through the respective electron beam passing opening port and vacuum seal. CONSTITUTION:A mirror body frame 1, in which a vacuum seal means 16 consisting of seal packings is provided under the outside of an opening end 15, is mounted on a visual field shifting mount 17 having an opening port 18 for passing an electron beam, permitting the shifting mount 17 longitudinally and laterally adjustable by each pair of screws 19. Said shifting mount 17 is arranged on the surface of a large structural body 21 through a similar vacuum seal means 20 provided under the outside of the opening port 18 to perform an evacuation through a vent 12 and detection 11 for a secondary electron beam or a signal 10 of characteristic X-ray. If a high degree of vacuum should be suspecious, vacuum clay 22 is used for preventing an intrusion of air. In this way, the surface of the large structural body can be nondestructively inspected and observed further with an enlarged field of vision. |
