Chapter/Index: Introduction | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Appendix
Apart from a long lifetime, the main requirements of the electron source are high brightness (electron current density per solid angle) and small spread of the kinetic electron energy. This requires materials with a small work function. Table 4963. Operating parameters and characteristics of electron sources
** ds -- Effective (or virtual) source diameter; ΔE -- Energy spread of the electron beam; φ -- Work function; T -- Operating temperature; E -- Electric field; Je -- current density of electron beam; β -- Electron-optical brightness at the cathode.
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