DIAMOND ELECTRON RADIATION CATHODE, ELECTRON SOURCE, ELECTRON MICROSCOPE, AND ELECTRON BEAM EXPOSER

摘要

Intended is to provide an electron radiation cathode of a high brightness, low energy dispersion and a long lifetime. Also intended is to provide a diamond electron radiation cathode, which can be sufficiently stably gripped, which is sharpened at its leading end and which is improved in a field intensity. The diamond electron radiation cathode (110) is characterized in that it is divided into at least three regions, that is, a leading end region (203) for irradiating a column-shaped leading end with electrons, a trailing end region (201) confronting in the longitudinal direction and adapted to be gripped, and a radially thinned intermediate region (202), in that the trailing end region has a sectional area of 0.2 mm<SUP>2</SUP>, in that the leading region has a sharpened leading end, and in that the radially thinned intermediate region has a sectional area of 0.1 mm<SUP>2</SUP> at most.