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Coverage of Laser Technology by Health Insurers

Description: This paper presents some empirical information on how insurers consider payment for new medical devices. It describes the survey results of medical directors affiliated with private health insurers about their coverage decisions using, as examples, three applications of lasers: laser angioplasty for opening narrowed or blocked coronary arteries; laser discectomy for treating herniated intervertebral discs; and photodynamic therapy (using a light–sensitive dye) for bladder cancer.
Date: August 1995
Creator: United States. Congress. Office of Technology Assessment.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Phase correction in two-crystal optical parametric oscillators

Description: The effect of the pump, signal, and idler wave phases on three-wave nonlinear parametric mixing is investigated in a series of single-pass-gain experiments. Measurements are made with two angle-tuned KTP crystals in a 532 nm pumped, walkoff-compensated, optical parametric amplifier that is seeded by an 800 nm cw diode laser. In one of the measurements the second crystal is orientated to have its effective nonlinearity d{sub eff.} of opposite sign to that of the first crystal, so that all mixing… more
Date: February 1, 1995
Creator: Armstron, D. J.; Alford, W. J.; Raymond, T. D. & Smith, A. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reduction in fiber damage thresholds due to static fatigue

Description: Damage mechanisms may occur during the transmission of Q-switched, Nd/YAG laser pulses through fused silica fibers. Fiber end-face characteristics, laser characteristics, and aspects of the laser-to-fiber injection typically determine dominant damage mechanisms. However, an additional damage process has been observed at internal sites where fibers were experiencing significant local stresses due to fixturing or bends in the fiber path. A transmission reduction prior to damage was typically not … more
Date: January 1, 1995
Creator: Setchell, R. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Advanced technologies for a compact rf linac FEL

Description: Advanced technologies such as the photoinjector, the short-period microwigglers, and harmonic lasing enable free-electron-laser operation in the infrared with a low-energy ({approximately} 10 MeV) electron beam and thus reduce the size and cost of FELs. The next-generation, rf-linac FEL will fit in a small laboratory and produce high-power, picosecond infrared.
Date: December 31, 1995
Creator: Nguyen, D. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A linear systems description of the CO{sub 2} laser based tangential imaging system

Description: We demonstrate that the phase variation produced by the projection of the density fluctuations onto a laser beam that is aligned tangent to the magnetic field lines in a toroidal plasma, is in fact a convolution of the density fluctuation profile in the tangency plane with a shift-invariant point spread function. Thus a spatial filter can be used to invert the corresponding transfer function to produce an undistorted image of the plasma density fluctuations at the tangency plane. Numerical simu… more
Date: January 1, 1995
Creator: Wright, E. L. J. & Nazikian, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Femtosecond OPOs at 3 microns and beyond: Design and performance issues related to the crystal properties of KTP and similar materials

Description: Femtosecond optical parametric oscillators (OPOs), synchronously pumped by Ti:Sapphire lasers, operating in the near infrared (IR) region are an important light source now under active development. The authors report the results of Ti:Sapphire synchronously pumped noncritically phase matched femtosecond OPOs that are based upon several crystals from the KTP family. The newly developed nonlinear crystal niobium doped KTP (Nb:KTP) has a greater birefringence than undoped KTP and is shown to exten… more
Date: February 1, 1995
Creator: Holtom, G. R.; Crowell, R. A. & Cheng, L. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Laser ultrasonic generation at the surface of a liquid metal

Description: The noncontacting nature of laser-based ultrasonic measurement has made it attractive in many applications. While most applications thus far involve solid samples, molten metals encountered in some stages of metal processing appear well suited to this technique. Possible applications for liquid metals include locating and characterizing the liquid/solid interface; characterizing a surface layer, contaminant, or alloying constituent; and measuring the temperature of the sample surface or bulk. T… more
Date: January 1, 1995
Creator: Walter, J. B.; Telschow, K. L. & Conant, R. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Transient radiation-induced absorption in materials for the DOI laser

Description: This is the final report on a series of experiments concerned with transient radiation-induced absorption in materials for a Cr,Nd:GSGG laser. Both the Sandia National Laboratories SPR III pulsed reactor and the Hermes III pulsed X-ray machine are used as radiation sources. The time dependence and the magnitude of the induced absorption in filter glasses and in doped and undoped LiNbO{sub 3} Q-switch materials have been measured. Gain has been observed in Cr,Nd:GSGG, the laser medium, when it i… more
Date: January 1, 1995
Creator: Brannon, P. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Development of a Superferric Undulator for Advanced Radiation Sources. CRADA Final Report

Description: Under this CRADA we have carried out a joint research and development program between the Accelerator Test Facility at the National Synchrotron Light Source Department at Brookhaven National Laboratory and Northrop-Grumman Corporate Research Center of Princeton New Jersey, for the purpose of developing an advanced superferric undulator for the generation of Free-Electron Laser (FEL) radiation. The intent of this work was to enhance the performance of the superconducting microundulator recently … more
Date: December 31, 1995
Creator: Ben-Zvi, Ilan & Ingold, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Phosphors for flat panel emissive displays

Description: An overview of emissive display technologies is presented. Display types briefly described include: cathode ray tubes (CRTs), field emission displays (FEDs), electroluminescent displays (ELDs), and plasma display panels (PDPs). The critical role of phosphors in further development of the latter three flat panel emissive display technologies is outlined. The need for stable, efficient red, green, and blue phosphors for RGB fall color displays is emphasized.
Date: July 1, 1995
Creator: Anderson, M.T.; Walko, R.J. & Phillips, M.L.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Sandia Combustion Research: Technical review

Description: This report contains reports from research programs conducted at the Sandia Combustion Research Facility. Research is presented under the following topics: laser based diagnostics; combustion chemistry; reacting flow; combustion in engines and commercial burners; coal combustion; and industrial processing. Individual projects were processed separately for entry onto the DOE databases.
Date: July 1, 1995
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

An optically-triggered semiconductor switch for high power laser beams

Description: The work involves research leading to an optically triggered switch for a high power laser pulse. The switch uses a semiconductor heterostructure whose optical properties are modified by a low power laser trigger such as a laser diode. Potential applications include optical control of pulsed power systems, control of medical lasers and implementation of security features in optical warhead architectures.
Date: April 1995
Creator: Chow, Weng W. & Warren, M. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Applications of microlens-conditioned laser diode arrays

Description: The ability to condition the radiance of laser diodes using shaped-fiber cylindrical-microlens technology has dramatically increased the number of applications that can be practically engaged by diode laser arrays. Lawrence Livermore National Laboratory (LLNL) has actively pursued optical efficiency and engineering improvements in this technology in an effort to supply large radiance-conditioned laser diode array sources for its own internal programs. This effort has centered on the development… more
Date: January 1, 1995
Creator: Beach, R. J.; Emanuel, M. A. & Freitas, B. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Flat panel planar optic display. Revision 4/95

Description: A prototype 10 inch flat panel Planar Optic display, (POD), screen has been constructed and tested. This display screen is comprised of hundreds of planar optic glass sheets bonded together with a cladding layer between each sheet where each glass sheet represents a vertical line of resolution. The display is 9 inches wide by 5 inches high and approximately 1 inch thick. A 3 milliwatt HeNe laser is used as the illumination source and a vector scanning technique is employed.
Date: May 1, 1995
Creator: Veligdan, J.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development of high damage threshold optics for petawatt-class short-pulse lasers

Description: The authors report laser-induced damage threshold measurements on pure and multilayer dielectrics and gold-coated optics at 1053 and 526 nm for pulse durations, {tau}, ranging from 140 fs to 1 ns. Damage thresholds of gold coatings are limited to 500 mJ/cm{sup 2} in the subpicosecond range for 1053-nm pulses. In dielectrics, qualitative differences in the morphology of damage and a departure from the diffusion-dominated {tau}1/2 scaling indicate that damage results from plasma formation and abl… more
Date: February 22, 1995
Creator: Stuart, B. C.; Perry, M. D. & Boyd, R. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Properties of transition metal-doped zinc chalcogenide crystals for tunable IR laser radiation

Description: The spectroscopic properties of Cr{sup 2+}, Co{sup 2+}, and Ni{sup 2+}-doped single crystals of ZnS, ZnSe, and ZnTe have been investigated to understand their potential application as mid-IR tunable solid-state laser media. The spectroscopy indicated divalent Cr was the most favorable candidate for efficient room temperature lasing, and accordingly, a laser-pumped laser demonstration of Cr:ZnS and Cr:ZnSe has been performed. The lasers` output were peaked at {approximately} 2.35 {mu}m and the h… more
Date: March 17, 1995
Creator: DeLoach, L.D.; Page, R.H. & Wilke, G.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

RTAP evaluation

Description: An in-depth analysis of the RTAP product was undertaken within the CNC associate program to determine the feasibility of utilizing it to replace the current Supervisory Control System that supports the AVLIS program. This document contains the results of that evaluation. With some fundamental redesign the current Supervisory Control system could meet the needs described above. The redesign would require a large amount of software rewriting and would be very time consuming. The higher level func… more
Date: January 23, 1995
Creator: Cupps, K.; Elko, S. & Folta, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A photocathode rf gun design for a mm-wave linac-based FEL

Description: In recent years, advances in the rf gun technology have made it possible to produce small beam emittances suitable for short period microundulators which take advantage of the low emittance beam to reduce the wavelength of FELs. At the Advanced Photon Source, we are studying the design of a compact 50-MeV superconducting mm-wave linac-based FEL for the production of short wavelengths ({approximately}300 nm) to carry out FEL demonstration experiments. The electron source considered for the linac… more
Date: July 1, 1995
Creator: Nassiri, A.; Berenc, T,; Foster, J.; Waldschmidt, G. & Zhou, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High efficiency oxide confined vertical cavity surface emitting lasers

Description: Optical loss is studied in devices with either two aligned apertures above and below the active region or with a single effective aperture above the active region. The latter exhibit slope efficiencies of up to 1 W/A.
Date: August 1, 1995
Creator: Lear, K. L.; Kilcoyne, S. P.; Schneider, R. P., Jr.; Choquette, K. D. & Hadley, G. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Rapid growth of diamond-like-carbon films by copper vapor laser ablation

Description: Visible light from a copper vapor laser (CVL) operating with 510 and 578 nm radiation (intensity ratio approximately 2:1), an average power of 100 W, a pulse duration of 50 ns, and a repetition frequency of 4.4 kHz has been shown to produce high quality diamond-like-carbon (DLC) films at fluences between 2x10{sup 8} and 5x10{sup 10} W/cm{sup 2}. Maximum deposition rates of 2000 {mu}m{center_dot}cm{sup 2}/h were obtained at 5x10{sup 8} W/cm{sup 2}. DLC films with hardness values of approximately… more
Date: April 1, 1995
Creator: McLean, W.; Warner, B. E. & Havstad, M. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Photoconductive semiconductor switches for firing sets and electro-optic modulators

Description: Optically activated GaAs switches operated in their high main mode are being used or tested for pulsed power applications as diverse as low impedance, high current pursers, and high impedance, low current Pockels cell or Q switch drivers. These are important to firing sets in munitions, lasers used in detonation of munitions, and lasers used in large weapons effects simulators (such as Jupiter). For firing, sets we have switched 2.8 kA at 3 kV dc charge in a very compact package. For driving Q … more
Date: July 1, 1995
Creator: Loubriel, G. M.; Zutavern, F. J.; Baca, A. G.; Hjalmarson, H. P.; Helgeson, W. D. & O`Malley, M. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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