NUMERICAL CALCULATIONS OF ELECTRON TRAJECTORIES IN THE 127 degree ANALYZER USING A POSITION-SENSITIVE DETECTOR UNDER CONDITIONS OF FRINGING FIELDS.

The theoretical performance of the 127 degree electron analyzer equipped with a position-sensitive detector has been discussed on the basis of a numerical calculation of electron trajectories. Including the Herzog correction in the calculation allows one to obtain good foci of electron onto almost all regions of the position-sensitive detector; it suggests that electron energy loss spectroscopy with high-energy resolution ( DELTA E/E//O equals 1. 6 multiplied by 10** minus **3) can be realized by the new analyzer. A nonlinear relation between the arriving point on the detector and electron energy has also been examined for some different fringing fields.