A microtip field‐emission electron microgun of a few cm3 has been developed for a novel type of semiconductor laser. The electron source is provided by an array of a field emissive microtips cathode each of 1.4 μm base diameter. The source current–voltage characteristic has been determined and its geometrical characteristics have been measured by collecting electrons on a phosphor screen in a region of constant electric field. We have observed that about 100 μA are typically emitted for gate‐cathode voltage (VGC) of 80 V with a half‐aperture angle of 28°. Beam focusing is then realized by two electrostatic lenses: a ‘‘thin hole lens’’ and a quadrupole lens. Using a cathode a 70×500 μm2 rectangular spot on a 10 kV biased anode has been obtained which yields a power density of about 3 kW/cm2. Less than 20% of the total electron beam (current) is lost in the electrostatic optics.

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