The purpose of this paper is to investigate the applicability of field
emission (FE) cathode arrays for a cathodoluminescent display device.
We proposed a tetrode structure which has a grid inserted between the
Mo emitter FE cathode arrays and the anode. The focusing properties o
f electron beams were measured using the Y2 SiO5:Tb phosphor, and a gr
een emission of about 66,700 cd/m2 was achieved at the anode current o
f about 90 mA/cm2 and the anode voltage of 8 kV in a vacuum chamber ke
pt at 1 x 10(-9) Torr, in which 14,700 Spindt-type cathode tips were u
sed. The experimental results showed that the dispersion of electron b
eams can be controlled to a considerable extent by the shape, distance
and voltage of the grid. An effect of SO2 gas on the emission propert
y of FE cathode arrays was measured, too.