Low-voltage, high-current electron gun

Abstract
A simple, high‐performance, electrostatically focused electron gun, which is useful over an energy range extending from a few electron volts to at least 500 eV, is described. The current is delivered in a beam ∼1 mm in diameter, with <50 mrad angular divergence and typically has a current over 1 mA at 100 eV. The design is small, compact, and rugged. This electron gun has been used successfully in both laboratory and sounding rocketexperiments.