| | Global imaging
The filter breaks down the electrons according to their energy (green with, red without energy loss), but the slit is not in the beam path. The second projector system combines all electrons into joint imaging.
The result corresponds to the quality of CTEM images, where the advantages of the filter are not utilised.
Elastic imaging
The slit is in the beam path. High voltage is set to the selected voltage, e.g. 200 kV. The slit allows only electrons without energy loss to pass. All electrons which have lost energy due to inelastic scattering are filtered out.
This mode enhances the contrast for all imaging modes such as bright field, dark field and diffraction.
Inelastic imaging (ESI)
The slit is in the beam path. High voltage is increased by the required energy DE. The slit position and the filter current remain constant. The slit only allows electrons to pass that have lost the DE energy and are therefore back to the rated voltage.
This mode is used for imaging with selective contrast on thin and thick specimens. |