Abstract: A plurality of semi-conductor diodes disposed in an array may be constructed to emit light when subjected to a particular voltage. This voltage reversely biases the semi-conductor diodes to break down the semi-conductor diodes and to provide for the emission of light upon breakdown. The breakdown occurs at the junction between a pair of electrodes in each semi-conductor diode. One of the electrodes may be an n electrode and the other electrode may be a p electrode. To break down the diode, a positive voltage (e.g. 3-5 volts) may be applied to the n electrode and a ground voltage may be applied to the p electrode. The diodes are so small that an array of 1024.times.1024 diodes can be disposed in a space approximately 0.4" square to act as pixels. The diodes may be scanned, as in a raster scan, preferably on a repetitive basis.