AN ELECTRON SPECTROMETER FOR USE WITH TRANSMISSION ELECTRON MICROSCOPE

A simple homogeneous-field magnetic prism spectrometer is described for use below the camera chamber of a conventional transmission electron microscope. The prism is designed for point-to-point focusing from the exit pupil of the electron microscope to the exit slit of the spectrometer. Energy spectra are scanned by varying the accelerating voltage to minimize chromatic effects in the microscope. Scanning coils are used to deflect an image or a diffraction pattern across an area-selecting aperture which also serves as the aperture stop for the spectrometer. A phase-sensitive periodic differential integrator is used to record the output from the scintillation counter detector.