Current-regulated field emission cathodes for use in a flat panel display in which low-voltage row and column address signals control a much higher pixel activation voltage

Claim 1

A current-regulated field emission display comprising: multiple row address lines; multiple column address lines; said row address lines intersecting said column address lines, with the intersection of a single row address line with a single column address line being associated with a single pixel within said display; a grid which is common to the entire display, and which is held at a first potential; groups of field emission cathodes, each group being associated with a particular pixel, each group being maintained at a second potential during periods of pixel inactivation, said second potential being close enough to said first potential so as to suppress field emission, and each group being maintained at a third potential during periods of pixel activation, said third potential being sufficiently low, with respect to said first potential, to induce field emission; at least one pull-down current path between the cathode group of each pixel and a node held at a fourth potential that is less than or equal to said third potential, said path comprising a current-regulating resistor and at least two field-effect transistors, said resistor and said transistors being series coupled, with said resistor being directly coupled to said node, at least one of said transistors being activatable in response to a signal on pixel's respective row address line, at least one other transistor being activatable in response to a signal on a that pixel's respective column address line, so as to enable switching of the potential applied to the cathode group associated with that pixel between said second potential and said third potential.