Electron-beam-addressed active-matrix spatial light modulator

A spatial light modulator contains a substrate, a plurality of overlying liquid-crystal cells, a plurality of respectively corresponding transistors, an electron-beam system ( and ), and a control component. Each transistor is in electrical communication with the corresponding liquid-crystal cell. The electron-beam system bombards each transistor with electrons that cause it to be selectively in (i) a non-conductive condition in which its channel-region electric field is substantially insufficient for conduction or (ii) a conductive condition in which its channel-region electric field is sufficient for at least partial conduction. During selected time periods when a transistor is in its conductive condition, the control component provides the transistor with a control signal that results in the polarization direction of specified light being selectively rotated in passing through the corresponding liquid-crystal cell.