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: Electrical contacts with low specific-contact resistance to In-based Group III-V compound semiconductors (e.g., p-InGaAsP) are formed by electron beam depositing a thin Pt layer directly on the semiconductor and sintering at about 450.degree.-525.degree. C. for about 5-30 minutes. Light emitting diodes without dark spot defects can be fabricated using this technique.

Abstract: Semiconductor light emitting devices, lasers and LEDs, are described in which the current flow channel is narrower near the top surface of the device and wider at its bottom near the active region. Also, described are several attenuation masks for fabricating the channels of these devices by particle bombardment.

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: Liquid crystal elements are interconnected in an array of rows and columns, which are not independent of one another, and are addressed by pulsed signals which together reduce the number of leads N required to operate the display. The interconnection scheme includes connecting together the last column to the second row, the penultimate column to the third row, etc., and the first column to the last row. In one embodiment for randomly accessing the display, the addressing scheme divides a row-select signal and a column-select signal into two time-wise sequential subsets: a first subset which includes pulses of one polarity in the time slots corresponding to the elements in that row, and a second subset which includes pulses of either polarity depending on which elements in that column are to be turned on and which off. The coincidence of two pulses of opposite polarity applied to an element from the row-select and column-select signals in sufficent to turn on that element.

Abstract: In an arc discharge device, a thin film bridges the gap(s) between adjacent electrodes, thereby enabling the arc discharge to be initiated and sustained by a low voltage D.C. supply. Application of the invention to both light source (e.g., laser) and material working (e.g., metal deposition) embodiments is described. One of the light source embodiments utilizes a cathode electrode which includes a pool of liquid Hg to generate a Hg ion plasma.

Abstract: A TJS light emitting diode (laser or LED) comprises an isotype double heterostructure (DH) and a V-groove which penetrates the intermediate layer of the DH. The groove is filled with a region of semiconductor material which enables carrier injection to occur from the region into the intermediate layer, or conversely, depending on the relative bandgaps of the layer and region. Real-refractive index guiding by the groove is described.

Abstract: Continuous wave laser oscillation has been achieved in a segmented plasma excitation and recombination device in the presence of a low-pressure background gas which rapidly flows across the segmented electrodes. Laser action has been observed in Cd I at 1.40, 1.43, 1.44, and 1.64 .mu.m. Also disclosed are techniques for allowing the background gas to flow between the electrodes and for confining the expanding plasmas with shields in the vicinity of the gaps between electrodes.

Abstract: A single-wavelength, bidirectional fiber optic transmission system is described in which at each terminal the output radiation of a light source (LED or semiconductor laser) is coupled through a small diameter hole in the active area of a photodiode into the core of a larger diameter transmission fiber. On the other hand, radiation propagating through the fiber in the opposite direction exits from the fiber with a large NA so that most of it is incident on the active area of the photodiode and little is lost through the hole. Also described are a number of photodiode configurations for use in such a system, as well as dual photodiodes to perform both signal detection and output monitoring functions.

Abstract: Thermal degradation of compound single crystal substrates (e.g., InP) containing a relatively volatile element (e.g., P) prior to LPE growth has been virtually eliminated by an improved protection technique. A partial pressure of the volatile element is provided by a solution (e.g., Sn-In-P) localized inside a chamber which is external to the LPE boat and which surrounds substrate prior to growth, thereby preventing thermal damage to the substrate surface. Applicability of the technique to other epitaxial growth processes (e.g., VPE and MBE) is also discussed.

Abstract: Photodiodes (10) are fabricated in a single step diffusion process which exploits the characteristic of certain acceptors to form an anomalous diffusion profile (VI) including shallow and deep fronts (VIa and b) joined by an upwardly concave segment (VIc). By performing this type of diffusion into a low-doped n.sup.- -type body (12) with a carrier concentration (VII) below that of the concave segment, a p.sup.+ --p.sup.- junction (15) is formed at the depth of the concave segment and a p.sup.- --n.sup.- junction (17) is formed at a greater depth. The zone (16) between the junctions is at least partially depleted and forms the active region of a p.sup.+ --p.sup.- --n.sup.- photodiode. Specifically described are InP:Cd photodiodes.

Abstract: In LPE boat-slider apparatus the boat, which carries the melts, is made of lower thermal conductivity material than the slider, which carries the substrate. Illustratively, the boat comprises sapphire and the slider comprises graphite. A confined-melt geometry is also described in which another slider, used to skim off thin portions of the melt, is also made of the lower thermal conductivity material.

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: Metal ellipsoidal particles are deposited on an ordered array of silicon dioxide posts. Each of the particles has dimensions that are less than the wavelength of a fundamental beam to be used in the generation of second harmonic radiation. The rows of particles in the ordered array are spaced at a distance that is less than one-half of the fundamental wavelength and greater than one-half of the second harmonic wavelength.

Abstract: Semiconductor light emitting devices, lasers and LEDs, are described in which the current flow channel is narrower near the top surface of the device and wider at its bottom near the active region. Also, described are several attenuation masks for fabricating the channels of these devices by particle bombardment.

Abstract: Photodiodes (10) are fabricated in a single step diffusion process which exploits the characteristic of certain acceptors to form an anomalous diffusion profile (VI) including shallow and deep fronts (VIa and b) joined by an upwardly concave segment (VIc). By performing this type of diffusion into a low-doped n.sup.- -type body (12) with a carrier concentration (VII) below that of the concave segment, a p.sup.+ -p.sup.- junction (15) is formed at the depth of the concave segment and a p.sup.- -n.sup.- junction (17) is formed at a greater depth. The zone (16) between the junctions is at least partially depleted and forms the active region of a p.sup.+ -p.sup.- -n.sup.- photodiode. Specifically described are InP:Cd photodiodes.

Abstract: Under photoluminescence (PL) excitation, the lateral spreading of photo-excited carriers can suppress the photoluminescence signal from double heterostructure (DH) wafers containing a p-n junction. In any DH with a p-n junction in the active layer, PL is suppressed if the power of the excitation source does not exceed a threshold value. This effect can be advantageously used for a nondestructive optical determination of the top cladding layer sheet conductance as well as p-n junction misplacement, important parameters for injection lasers and LEDs.

Abstract: Numerous laser transitions in the visible and near-infrared in four metal vapors (Li, Al, Ca, and Cu) have been observed in the recombination phase of the expanding plasmas produced by a segmented plasma device employing foil electrodes. Also described is a segmented vapor plasma discharge in using Ni foil electrodes.

Abstract: Selected portions of the interior surface of a substrate tube, or of the cladding or core layers deposited on the interior surface of the substrate tube, are treated by one or more process steps such as shaping, diffusing, leaching, or depositing. Patterning processes such as photolithography and lift-off are employed to define the selected portions. The resulting core and/or cladding layers of the fiber can be made to have a variety of geometric shapes and composition profiles useful, for example, in realizing birefringent fibers and multiple-core fibers. Also described is the similar treating of metal layers and the incorporation of such layers into the fiber.

Abstract: A method of liquid phase epitaxy is disclosed for growing a plurality of different layers on each of a plurality of semiconductor wafers during a single heating cycle. Each of a series of melts, each corresponding to a layer to be grown, is divided, in succession, into aliquant portions and a remainder portion. Each aliquant portion is contacted by one or more wafers, and epitaxial growth occurs as the temperature is lowered. Provision of a remainder portion enables a two-phase melt, and a wafer contacts only one distinct melt at a time.After a growth step, the next successive melt likewise is separated into aliquant portions and a remainder portion, the wafers are removed from the preceding melt chambers and placed in contact with the newly formed aliquant portions, and growth of another layer ensues from another drop in temperature. The process is repeated for each melt provided.Apparatus for carrying out the method also is described.