Abstract: Prior to packaging, semiconductor lasers are purged by being subjected first to high temperature and high current simultaneously so as to suppress stimulated emission and stress the shunt paths which allow leakage current to flow around the active region. A prudent, but nonessential, second step is to lower the temperature and/or current so that the lasers emit stimulated emission (preferably strongly, near the peak output power), thereby stressing the active region. Lasers subjected to such a purge exhibit stabilized degradation rates in short times (of the order of a few hours) and provide a robust population which meets the performance criteria of long lifetime systems.

Abstract: Disclosed is an optical device producing single mode laser emission. The device includes a semiconductor laser which would normally emit a number of closely spaced longitudinal modes and a filter which receives light from the laser active layer and reflects light back to the active layer. The filter includes at least one thin, optically absorbing layer, a dielectric layer, and a reflecting layer. The thickness and refractive indices of the layers are such that the filter reflectivity has a number of narrow maxima, but only one which lies within the gain bandwidth of the laser. The width of the peak and the background amplitude between peaks is such that only a single longitudinal mode of the laser is allowed to oscillate.

Abstract: A semiconductor heterojunction optical loss modulator section (30), having an anti-reflection coating (52) on its optical output beam facet (32), is located with an opposite facet (31) optically coupled to, and closely spaced from, a semiconductor heterojunction laser section (20) having substantially the same cross-section structure as the loss modulator section (30). The laser section is operated CW in a single mode. In this way, the output beam (50) emanating from the laser section (20) and passing through the anti-reflection coating (52) can be coupled into an optical fiber (60) for transmission purposes. This output beam (50) is substantially single frequency and is intensity modulated, in a signal-pattern independent fashion, in accordance with an electrical signal applied to the loss modulator section (30).

Abstract: Room temperature laser action is achieved in a cathode ray tube (CRT) in which the target includes a plurality of semiconductor layers: a thin, wide bandgap buffer layer; a thicker, narrow bandgap active layer; and a much thicker wide bandgap cavity-length-adjusting layer. The light beam direction is essentially parallel to the e-beam direction and hence is scannable.

Abstract: The target of a CRT comprises a single crystal substrate (e.g., YAG) on which are formed a plurality of color stripe triads of epitaxial material. Each stripe triad has three epitaxial layers in a staircase geometry and is overlayed with a metal stripe. The metal stripes are the fingers of a pair of interdigitated electrodes. A single e-beam scans the stripes horizontally, and a sequence of current pulses generated in the electrodes precisely defines the horizontal position of the beam relative to the triads. This information is used to precisely time the beam modulation for introducing color signals. The CRT is particularly suited to miniaturization and application in projection systems.

Abstract: The invention is a matrixing system, involving optical fibers, for accessing data encoded on an optical disk. Illustratively, a plurality of first fiber bundles couples optical sources to disk locations along angular coordinates, and a plurality of second fiber bundles couples disk locations along radial coordinates to optical detectors. Selective activation of a particular source and particular detector enables a predetermined disk location to be read. The system is characterized by a random access time on the order of 100 .mu.s or less.

Abstract: The specification describes a video storage system employing a unique memory tube. The tube employs a single read-write electron beam. The storage target is an insulating grid formed directly on a semiconductor substrate. Since the grid is supported, it can be made very fine and the processing advantageously uses photolithographic techniques.