Electron microscope specimen scan chamber - has carriage drive along beam axis with pusher roller engaging carriage slot

摘要

A small sized chamber for manipulating specimens analysed by electron microscope is achieved by a compact mechanism controlling the specimen displacement along the instrument axis when sharp change in magnification is implemented. It ensures a constant scan angle of the electron beam and permits precise setting of the tested specimen. The sealed housing contains the stage for the specimen and the drives for its shift along three mutually perpendicular axes of which one is aligned with the electron-optical axis. The latter drive includes an eccentric pusher with shaft featuring a hollow finger holding the spring-biased slide and a roller bearing against the slot of the carriage connected to the slide. The stage with the specimen is set in relation to the X/Y coordinates and inclined as required w.r.t. the Z axis of the instrument. The setting is carried out with handle and gears transmit the motion to a shaft for the advance of the stage. The stage tilt ie controlled by a handle while positioning along the Y axis requires turning of the handle with the shaft moving in the stationary nut. During the shift, the box-shaped frame is displaced along the Y axis due to gear train linkage without interference of any of the other drives.