John S. Toeppen
Method for Optical and Mechanically Coupling Optical Fibers
U.S. Patent 5,560,760
October 1, 1996
An inexpensive technique to splice optical fibers that does not cause deformation of the host fibers, does not require repeated thermal cycling of the optical fibers, does not cause thermal and photonic degradation of the fibers even at high power applications, does not cause the fibers to prematurely deteriorate with age, and is suitable for use with optical fibers having a core diameter of as much as 1,000 micrometers or greater. A solder-glass frit having a melting point lower than the melting point of the optical fibers is used to splice the two optical fibers together.

Rex Booth
Charge Line Quad Pulser
U.S. Patent 5,563,457
October 8, 1996
A quartet of parallel coupled planar triodes that is removably mounted in a quadrahedron-shaped PCB structure. Releasable brackets and flexible means attached to each triode socket make triode cathode and grid contact with respective conductive coatings on the PCB and with a detachable cylindrical conductive element enclosing and contacting the triode anodes.The configuration permits quick and easy replacement of faulty triodes. By such orientation, the quad pulser can convert a relatively low and broad pulse into a very high and narrow pulse. A maximum impedance mismatch within a quartet planar triode circuit of less than 10% is maintained.

Thomas E. McEwan
Precision Digital Pulse Phase Generator
U.S. Patent 5,563,457
October 8, 1996
A timing generator comprising a crystal oscillator connected to provide an output reference pulse. A resistor-capacitor combination is connected to provide a variable-delay output pulse from an input connected to the crystal oscillator. A phase monitor is connected to provide duty-cycle representation of the reference and variable-delay output pulse phase. An operational amplifier drives a control voltage to the resistor-capacitor combination according to currents integrated from the phase monitor and injected into summing junctions. A digital-to-analog converter injects a control current into the summing junctions according to an input digital control code.

Kurt H. Weiner and Thomas W. Sigmon
Process for Forming Retrograde Profiles in Silicon
U.S. Patent 5,565,377
October 15, 1996
A process for the formation of retrograde profiles in silicon, either previously doped crystalline or polycrystalline silicon, or for introducing dopant into amorphous silicon so as to produce the retrograde profiles. This process involves the formation of higher dopant concentrations in the bulk than at the surface of the silicon. By this process, n- and p-well regions in CMOS (complementary metal oxide silicon) transistors can be formed by a simple, flexible, and inexpensive manner. This technique has particular application in the manufacture of silicon integrated circuits where retrograde profiles are desired for the n- and p-well regions of CMOS transistor technology and for buried collectors in bipolar transistors.

Daniel W. Shimer and Arnold C. Lange
E-Beam High Voltage Switching Power Supply
U.S. Patent 5,566,060
October 15, 1996
A circuit device for generating a ground-level voltage feedback signal for controlling the output voltage of one of a plurality of dc-dc converter modules having their outputs connected in series to form a supply output lead. Each module includes a switching device for producing a pulsating voltage of controlled duty cycle, an inductor mechanism for converting the pulsating voltage into a smooth direct current, and an inverter mechanism for producing from the direct current an alternating current through the primary of a transformer. The transformer has at least one secondary winding inductively coupled to the primary winding for producing an output voltage of the module.

George P. Roberson and Michael F. Skeate
Image Matrix Processor for Fast Multidimensional Computations
U.S. Patent 5,566,341
October 15, 1996
An apparatus for multidimensional computation that comprises a computation engine, including a plurality of processing modules. The processing modules are configured in parallel and compute respective contributions to a computed multidimensional image of respective two-dimensional data sets. A storage system is provided that stores the multidimensional data sets, and a switching circuit routes the data among the processing modules in the computation engine and the storage system. The processing modules include a programmable local host, by which they may be configured to execute a plurality of different types of multidimensional algorithms.

Gary W. Johnson
Apparatus for Controlling the Scan Width of a Scanning Laser Beam
U.S. Patent 5,568,255
October 22, 1996
A system whereby the scan width of a swept ring-dye laser or a semiconductor diode laser can be measured and controlled in real-time with a resolution better than 0.1%. Scan linearity, or conformity to a nonlinear scan waveform, can be measured and controlled. The system consists of a Fabry-Perot interferometer, three CAMAC interface modules, and a microcomputer running a simple analysis and proportional-integral control algorithm. With additional modules, multiple lasers can be simultaneously controlled. Also included is an embodiment implemented on an ordinary personal computer with a multifunction plug-in board.

Kurt H. Weiner
Method for Shallow Junction Formation
U.S. Patent 5,569,624
October 29, 1996
A doping sequence that reduces the cost and complexity of forming source/drain regions in complementary metal oxide silicon (CMOS) integrated circuit technologies. The process combines the use of patterned excimer laser annealing, dopant-saturated spin-on glass, silicide contact structures, and interference effects created by thin dielectric layers to produce source and drain junctions that are ultrashallow in depth but exhibit low sheet and contact resistance. The process uses no photolithography and can be achieved without the use of expensive vacuum equipment. The process margins are wide, and yield loss due to contact of the ultrashallow dopants is eliminated.

Alexander R. Mitchell, Philip F. Pagoria, and Robert D. Schmidt
Vicarious Nucleophilic Substitution to Prepare 1,3-Diamino-2,4,6-Trinitrobenzene or 1,3,5-Triamino-2,4,6-Trinitrobenzene
U.S. Patent 5,569,783
October 29, 1996
A process that is milder and more environmentally benign to easily convert nitroaromatic compounds to DATB, TATB, or mixtures thereof by using processes that avoid strong acids (H2SO4, HNO3) at elevated temperatures (100 to 150°ree;C) and the need for noxious materials such as ammonia, thionyl chloride, and hydrogen sulfide. DATB and TATB can be useful specialty explosives. TATB can also be used for the preparation of benzenehexamine, a starting material for the synthesis of novel materials such as optical imaging devices, liquid crystals, and ferromagnetic compounds.

Howard Nathel, John H. Kinney, and Linda L. Otis
Method for Detection of Dental Caries and Periodontal Disease Using Optical Imaging
U.S. Patent 5,570,182
October 29, 1996
A method of optical imaging that may be used both for the detection of dental caries and for the diagnosis and monitoring of gingivitis. Optical radiation is used in the wavelength region between 500 and 1,400 nanometers, where carious dental tissue is much more strongly absorbing than healthy tissue, so that transmitted or reflected optical radiation can be used to create a shadowgram of structures within the dental tissue. The same wavelength region used for the detection and location of tissue boundaries may be used to diagnose and monitor the progress and treatment of gingivitis.

Joseph T. Salmon
Split-Field Pupil Plane Determination Apparatus
U.S. Patent 5,570,189
October 29, 1996
An apparatus for locating a pupil plane following relay telescope optics along an optical path using a pair of optical wedges disposed side by side on the optical path for splitting an incident beam of collimated light on the optical path to provide two parallel side-by-side beams of collimated light on the optical path, the parallel side-by-side beams of collimated light being provided such that they diverge while being parallel to the path of the incident beam of collimated light.

George G. Pollock
Precision Control of High Temperature Furnaces Using an Auxiliary Power Supply and Charged Particle Current Flow
U.S. Patent 5,597,501
January 28, 1997
A high-temperature furnace with two power supplies. A main power supply connected to a heating element in the furnace heats the furnace in the traditional manner. An auxiliary power supply introduces a current flow through charged particles between the heating element and an object holder. The main power supply provides the bulk heating power; the auxiliary provides temperature control.


Laboratory scientists Paul Coronado, Dan Calef, Bob Sanner, and Lucy Hair were recently selected by the Society of Automotive Engineers to be honored by the Partnership for New Generation Vehicles (PNGV) for their contribution to the development of affordable, energy-efficient, nonpolluting vehicles to get up to 80 miles per gallon. On March 31 in Washington, D.C., they received medals from Vice President Al Gore. PNGV is a collaboration of eight federal agencies, the U.S. Council for Automotive Research, Chrysler, Ford, General Motors, and 18 laboratories, among them Livermore, Los Alamos, and Sandia national laboratories. Its goal is to select the most promising new technologies by 1997 and produce a concept car by the year 2000. The Livermore team was honored for the development of aerogels to be catalysts for the next-generation vehicles. Sanner, a materials chemist, made materials that Coronado, a chemist, developed into aerogels, which were tested for use as a catalyst. Calef, a theoretical chemist, did modeling to determine which metals would or would not work in an aerogel environment, and Hair, a chemical engineer, served as principal investigator on the project.

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