Spatial resolution and detection sensitivity in microanalysis by electron loss selected imaging.

An electron energy filter of the Castaing-Henry type in a high resolution transmission electron microscopy was tested for sensitivity and spatial resolution at a specific electron energy loss in energy selected images of a murine leukaemia virus. Electron spectroscopic images of phosphorus within the virus membrane bilayer demonstrated a best spatial resolution between 0.3 and 0.5 nm and a sensitivity of 2 X 10(-21) g.