The invention includes field emitters, field emission displays (FEDs), monitors,
computer systems and methods employing the same for providing uniform electron
beams from cathodes of FED devices. The apparatuses each include electron beam
uniformity circuitry. The electron beam uniformity circuit provides a grid voltage,
VGrid, with a DC offset voltage sufficient to induce field emission
from a cathode and a periodic signal superimposed on the DC offset voltage for
varying the grid voltage at a frequency fast enough to be undetectable by the human
eye. The cathodes may be of the micro-tipped or flat variety. The periodic signal
may be sinusoidal with peak-to-peak voltage of between about 5 volts and about
50 volts.