Science.gov

Sample records for flash lamp pumped

  1. Laser head for simultaneous optical pumping of several dye lasers. [with single flash lamp

    NASA Technical Reports Server (NTRS)

    Mumola, P. B.; Mcalexander, B. T. (Inventor)

    1975-01-01

    The invention is a laser head for simultaneous pumping several dye lasers with a single flash lamp. The laser head includes primarily a multi-elliptical cylinder cavity with a single flash lamp placed along the common focal axis of the cavity and with capillary tube dye cells placed along each of the other focal axes of the cavity. The inside surface of the cavity is polished. Hence, the single flash lamp supplies the energy to the several dye cells.

  2. Coumarin-4 laser efficiency up to 0. 14% under coaxial flash-lamp pumping

    SciTech Connect

    Zhang, F.G.; Yu, C.L.

    1987-02-01

    Under coaxial flash lamp pumping the laser efficiency of coumarin-4 in slightly basic ethyl alcohol solution as an active medium has reached a value of 0.14%. That is three times higher than that in the basic aqueous solution. Its tunable wavelength range of laser output has extended from 440 to 510 nm with the maximum at 460 nm.

  3. The effect of laser-rod properties on the energy transfer efficiency of pumping cavities using helical flash lamps.

    PubMed

    Skinner, D R

    1969-07-01

    Monte Carlo calculations of energy transfer efficiency are presented for a wide range of configurations typical of practical large ruby laser systems using helical flash lamps. Details of mathematical models used are given. It is shown that the efficiency of the pumping cavity is greatly reduced if the ruby surface is roughened to form a perfect diffuser. Removal of the core of the ruby to form an annular cylinder causes a significant loss of efficiency for smooth rubies only. Also, the efficiency increases significantly with increasing ruby length and diameter, but there is only a marginal improvement with increasing ruby absorption coefficient. PMID:20072455

  4. Flash-lamp pumped Pr:YAP laser operated at wavelengths of 747 nm and 662 nm

    NASA Astrophysics Data System (ADS)

    Fibrich, Martin; Jelínková, Helena; Šulc, Jan; Nejezchleb, Karel; Škoda, Václav

    2009-02-01

    Successful room-temperature generation of Pr:YAP laser radiation at wavelengths of 747 nm and 662 nm was demonstrated. A flash-lamp pumped Pr:YAP laser was operated in free-running pulsed regime at room temperature. Permanent laser action was reached by means of a special UV color glass plate filter placed directly into the laser cavity. The maximum output energy and pulse length reached at wavelengths of 747 nm and 662 nm were 102 mJ, 92 μs and 6.1 mJ, 47.5 μs, respectively. The laser beam parameter M2 ~ 1.5 was measured when the 662 nm wavelength was generated. In the case of 747 nm wavelength generation, M2 ~ 1.2 was reached with a diaphragm inside the resonator. For different pumped energy values, the line shape and linewidth remained stable for both cases.

  5. Rapid flash lamp

    SciTech Connect

    Gavenonis, Thomas L.; Hewitt, William H.

    1989-06-06

    A method and apparatus for providing low peak time and pulse width actinic energy from a lamp by varying the input energy of a capacitive ignition circuit having relatively high voltage to the lamp. The lamp comprises a pair of electrodes disposed within a light transparent envelope in which a combustible and an oxidizing gas reaction combination is located. The combustible is preferably shredded zirconium which is in contact with and provides an electrical discharge path between the electrodes. The gas is preferably pressurized oxygen.

  6. Rapid flash lamp

    DOEpatents

    Gavenonis, Thomas L.; Hewitt, William H.

    1989-01-01

    A method and apparatus for providing low peak time and pulse width actinic energy from a lamp by varying the input energy of a capacitive ignition circuit having relatively high voltage to the lamp. The lamp comprises a pair of electrodes disposed within a light transparent envelope in which a combustible and an oxidizing gas reaction combination is located. The combustible is preferably shredded zirconium which is in contact with and provides an electrical discharge path between the electrodes. The gas is preferably pressurized oxygen.

  7. Investigation of 2.1-micron lasing properties of Ho:Tm:Cr:YAG crystals under flash-lamp pumping at various operating conditions

    NASA Technical Reports Server (NTRS)

    Kim, Kyong H.; Choi, Young S.; Barnes, Norman P.; Hess, Robert V.; Bair, Clayton H.; Brockman, Philip

    1993-01-01

    Flash-lamp-pumped normal-mode and Q-switched 2.1-micron laser operations of Ho:Tm:Cr:YAG crystals have been evaluated under a wide variety of experimental conditions in order to determine an optimum lasing condition and to characterize the laser outputs. Q-switched laser-output energies equal to, or in some cases exceeding the normal-mode laser energies, were obtained in the form of a strong single spike through an optimization of the opening time of a lithium niobate Q switch. The increase of the normal-mode laser slope efficiency was observed with the increase of the Tm concentration from 2.5 to 4.5 at. pct at operating temperatures from 120 K to near room temperature. Laser transitions were observed only at 2.098 and 2.091 microns under various conditions. The 2.091-micron laser transition appeared to be dominant at high-temperature operations with low-reflective-output couplers.

  8. Multi-lamp laser pumping cavity

    SciTech Connect

    Kuppenheimer, J.D. Jr.

    1987-07-21

    An optically pumped laser comprises: A. a cylindrical laser rod having a longitudinal central rod axis; B. cylindrical lamps for optically pumping the laser rod. The lamps have longitudinal central lamp axes parallel to the rod axis. The lamps being so located with respect to each other and to the laser rod as to define in cross section a base line associated with each lamp and extending between the rod axis and the lamp axis of the associated lamp. The base lines being equal in length and equiangularly spaced; and C. a reflector wall consisting essentially of first and second wall sections associated with each lamp, the cross sections of the first and second wall sections associated with a given lamp essentially following first and second curves extending from a lamp cusp associated with the given lamp to second and first rod cusps, respectively, associated with the given lamp. The first and second curves consist of the loci of points to which the sums of the distances, exterior to the laser rod and the given lamp, from first and second rod starting points, respectively, associated with the given lamp and from first and second lamp starting points, respectively, on the given lamp equal a fixed quantity.

  9. EUV resist processing with flash-lamp

    NASA Astrophysics Data System (ADS)

    Santillan, Julius Joseph; Kaneyama, Koji; Morita, Akihiko; Fuse, Kazuhiko; Kiyama, Hiroki; Asai, Masaya; Itani, Toshiro

    2012-03-01

    The reduction of line width roughness (LWR) remains a difficult issue for very fine patterns obtained with extreme ultraviolet (EUV) lithography. Thus, the investigation of LWR-reduction from the viewpoint of resist processing has become necessary. Alternative bake processes, such as the flash-lamp (FL) has been proven feasible as for application in EUV resists. This work focuses on initial investigations for its use in post-development bake (post bake or PB). A polyhydroxystyrene-acryl hybrid EUV model resist was utilized and comparisons with 'no bake' and conventional hot-plate PB conditions were made. As a result, relatively improved LWR was obtained with FL PB with minimal effect on lithographic performance. Moreover, in the course of these experiments, two types of resist reflow mechanisms assumed to be the primary basis for the LWR improvement achieved, are discussed.

  10. CW arc-lamp-pumped alexandrite lasers

    SciTech Connect

    Samelson, H.; Walling, J.C.; Wernikowski, T.; Harter, D.J.

    1988-06-01

    The performance characteristics of arc-lamp- (Xe and Hg) pumped, CW alexandrite lasers are described in detail. The modes of operation considered are free running, tuned, and repetitively Q-switched. The experimental arrangement and apparatus are also outlined. The experimental results are discussed in terms of a steady-state model, and the areas of agreement and difficulty are pointed out.

  11. 49 CFR 234.253 - Flashing light units and lamp voltage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Flashing light units and lamp voltage. 234.253 Section 234.253 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD....253 Flashing light units and lamp voltage. (a) Each flashing light unit shall be inspected...

  12. 49 CFR 234.253 - Flashing light units and lamp voltage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Flashing light units and lamp voltage. 234.253 Section 234.253 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD....253 Flashing light units and lamp voltage. (a) Each flashing light unit shall be inspected...

  13. Portable flash lamp reflectance analyzer system and method

    NASA Technical Reports Server (NTRS)

    Kalshoven, James Edward (Inventor)

    1999-01-01

    The system and method allow spectroscopic analysis of vegetation or the like without effects from changing sun and cloud conditions, undesired portions of the area of interest or atmospheric disturbances. The system (1) includes a light source (5) such as a xenon flash lamp, a telescope (7), a spectrometer (9), an analog/digital converter (11), a memory (13), a display (15), and an on-board microprocessor (17) or a port (19) for attachment to a laptop computer. The system is taken to an area of interest in the woods (step 41), the vegetation is illuminated from below (step 43) and data are taken (step 45).

  14. 49 CFR 234.253 - Flashing light units and lamp voltage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Flashing light units and lamp voltage. 234.253 Section 234.253 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... Maintenance, Inspection, and Testing Inspections and Tests § 234.253 Flashing light units and lamp voltage....

  15. An Electronic Flash Lamp System to Replace the Traditional, Explosively-Driven Light Source

    SciTech Connect

    Stigman, W L; Kihara, R; Scarpetti, R D

    2002-09-25

    Electronic flash lamps are being developed at the Lawrence Livermore National Laboratory (LLNL). These lamps are intended to replace the traditional explosively driven Argon-gas filled light sources (Argon candles) that are currently used to provide illumination for high speed rotating mirror-framing cameras. At Livermore, we are developing an electronic flash lamp system that can match or exceed the light output of a traditional Argon candle. These systems utilize a Plasma Arc Lamp developed by PRISM Science Inc of Chatham, MA, USA. In the past, high-speed photography requiring explosively driven light sources were a one-time-only event that destroyed fixtures and optical alignment. The electronic flash lamp system, utilizing the Plasma Arc Lamp, will replace the explosively driven lighting systems and provide the capability to dry run experimental setups and repeat tests without damage to the experimental set-up. The electronic flash lamp system eliminates the problem of collateral damage to the experiment and does not add to the overall amount of explosives needed for a single test. Since the Pulsed-Power driver is remotely located, only the flash lamp itself is destroyed when the explosive shot is fired. The flexible geometry of this light source also enables the user to create complex light patterns as well as photograph very large areas with a single lighting system. This electronic flash lamp system will provide an extremely bright, stable, and repeatable light source for rotating-mirror framing cameras operating at one million frames per second, using both black & white or color films. The design of the Pulsed-Power driver and the flash lamp, along with experimental data and results will be discussed.

  16. [Study on the discharge properties of xeon flash lamp and experimental measurement].

    PubMed

    Zhao, You-Quan; Miao, Pei-Liang; He, Feng; Gu, Jian; Zhai, Rui-Wei

    2014-07-01

    The Xenon flash lamp is a new type of light source for analytical instrument. The present paper analyzed the discharge process of xenon flash lamp, presented the discharge test system, and conducted experimental measurement of the voltage, current and optical pulse signal in the process of discharge. The results show that in the preliminary discharge, the free electron concentration was at a low level, so the energy was at a low level, then following the gas discharge, numerous free electrons formed in the lamp, resultin in the increase in the concentration of free electrons, therefore discharge current rised rapidly and voltage reduced. The lamp released photons to generate light pulse in the moment of ionic recombination, The pulse xenon lamp light energy output and spectral characteristic is related to electron energy in recombination and combination level of xenon, if the input energy and the energy consumption of the xenon lamp is inconsistent, it will lead to repeated capacitor charging and discharging and produce oscillation waveform. This paper is very useful for understanding the process of xenon lamp discharge, optimizing the driver circuit and the production of xenon flash lamp. PMID:25269320

  17. Effect of flash lamp annealing on electrical activation in boron-implanted polycrystalline Si thin films

    SciTech Connect

    Do, Woori; Jin, Won-Beom; Choi, Jungwan; Bae, Seung-Muk; Kim, Hyoung-June; Kim, Byung-Kuk; Park, Seungho; Hwang, Jin-Ha

    2014-10-15

    Highlights: • Intensified visible light irradiation was generated via a high-powered Xe arc lamp. • The disordered Si atomic structure absorbs the intensified visible light. • The rapid heating activates electrically boron-implanted Si thin films. • Flash lamp heating is applicable to low temperature polycrystalline Si thin films. - Abstract: Boron-implanted polycrystalline Si thin films on glass substrates were subjected to a short duration (1 ms) of intense visible light irradiation generated via a high-powered Xe arc lamp. The disordered Si atomic structure absorbs the intense visible light resulting from flash lamp annealing. The subsequent rapid heating results in the electrical activation of boron-implanted Si thin films, which is empirically observed using Hall measurements. The electrical activation is verified by the observed increase in the crystalline component of the Si structures resulting in higher transmittance. The feasibility of flash lamp annealing has also been demonstrated via a theoretical thermal prediction, indicating that the flash lamp annealing is applicable to low-temperature polycrystalline Si thin films.

  18. Optimum flash lamp annealing conditions for fabrication of low dose ion-implanted Si solar cells

    NASA Astrophysics Data System (ADS)

    Usami, A.; Nishioka, H.; Inoue, Y.

    1984-06-01

    A method to fabricate silicon solar cells was developed around low dose (nonamorphized) ion implantation and Xe flash lamp annealing under assist heating (350-550 C). Solar cells fabricated by low dose B-11/+/ (p+/n-type cell) and P-31/+/ (n+/p-type cell) implantation and flash lamp annealing showing a high efficiency of about 10.4 percent (AM2) without AR coating and BSF structures. The results were compared with those of high dose implanted cells reported previously (in this transaction). Effects of assist heating temperature were also examined.

  19. Rapid measurement of spatial light distribution of a short-arc xenon flash lamp.

    PubMed

    Zhao, Youquan; Guo, Dexia; Liu, Xiao; Wang, Lingli; Jiang, Nan; Wang, Xianquan

    2016-08-20

    Small short-arc xenon flash lamps, yielding high energy and ultraviolet radiation without cooling structures, provide ideal analytic-instrument light. Improving instrument designs requires accurately determining spatial optical-flux distribution. Thus, this paper presents rapid scanning of a xenon lamp's central light intensity using a high-sensitivity photodiode to capture short light pulses. Results show two-dimensional optical illumination patterns. In the horizontal mode, the anode and cathode lie in the target plane. In the vertical mode, the two electrodes are centered in a circle. Thus, because the xenon lamp's spatial light flux varies by orientation and main driving voltage, we recommend sampling light horizontally in front of the lamp across small angles. PMID:27556976

  20. 15 KJ FLASH LAMP, POWER CONDITIONING UNIT DESIGNED FOR SAFTY, RELIABILITY & MANUFACTURABILITY*

    SciTech Connect

    James, G; Merritt, B; Dreifuerst, G; Strickland, S

    2007-08-07

    A 15kJoule, Flash Lamp Power Conditioning Unit has been successfully designed, developed, and deployed in the National Ignition Facility (NIF) Preamplifier Modules (PAM). The primary design philosophy of this power conditioning unit (PCU) is safety, reliability, and manufacturability. Cost reduction over commercially equivalent systems was also achieved through an easily manufactured packaging design optimized to meet NIF requirements. While still maintaining low cost, the PCU design includes a robust control system, fault diagnostic system, and safety features. The pulsed power design includes 6 PFN modules, each including a dual series injection trigger transformer, that drive a total of 12 flash lamp loads. The lamps are individually triggered via a 20kV pulse produced by a 1kV, MCT switched capacitive discharge unit on the primary side of the trigger transformer. The remote control interface includes an embedded controller that captures flash lamp current wave forms and fault status for each shot. The embedded controller provides the flexibility of remotely adjusting both the main drive voltage from 1.6 to 2.5 kV and the trigger voltage from 0 to 20 kV.

  1. A flash-lamp based device for fluorescence detection and identification of individual pollen grains

    NASA Astrophysics Data System (ADS)

    Kiselev, Denis; Bonacina, Luigi; Wolf, Jean-Pierre

    2013-03-01

    We present a novel optical aerosol particle detector based on Xe flash lamp excitation and spectrally resolved fluorescence acquisition. We demonstrate its performances on three natural pollens acquiring in real-time scattering intensity at two wavelengths, sub-microsecond time-resolved scattering traces of the particles' passage in the focus, and UV-excited fluorescence spectra. We show that the device gives access to a rather specific detection of the bioaerosol particles.

  2. Transient absorption in water-micellar solutions of rhodamine 6G with flash lamp excitation

    SciTech Connect

    Levin, M.B.; Cherkasov, A.S.

    1986-06-01

    This paper studies the kinetics of transient losses in water-micellar solutions of rhodamine 6G by using flash lamp excitation. During the experiments, the laser radiation energy was measured, the time evolution of stimulated emission spectra was recorded; pulse shape was monitored by an oscillograph. The change of generation characteristics of water-micellar solutions of rhodamine 6G as a function of cyclooctatetraene concentration is shown.

  3. Homogenization of the melting depth in SiC on Si structures during flash lamp irradiation

    NASA Astrophysics Data System (ADS)

    Voelskow, Matthias; Skorupa, Wolfgang; Smith, Mark P.; McMahon, Richard A.

    2005-12-01

    Flash lamp annealing of heteroepitaxial silicon carbide on silicon structures involves melting the silicon below the SiC layer but the faceted nature of the liquid-solid interface leads to unacceptable surface roughness. This letter describes a method of controlling melting by using a melt stop created at a controlled depth below the Si /SiC interface by implanting a high dose of carbon, which significantly increases the silicon melting temperature. Results confirm the effectiveness of this approach for increasing surface uniformity, making liquid phase processing compatible with standard device fabrication techniques.

  4. Homogenization of the melting depth in SiC on Si structures during flash lamp irradiation

    SciTech Connect

    Voelskow, Matthias; Skorupa, Wolfgang; Smith, Mark P.; McMahon, Richard A.

    2005-12-12

    Flash lamp annealing of heteroepitaxial silicon carbide on silicon structures involves melting the silicon below the SiC layer but the faceted nature of the liquid-solid interface leads to unacceptable surface roughness. This letter describes a method of controlling melting by using a melt stop created at a controlled depth below the Si/SiC interface by implanting a high dose of carbon, which significantly increases the silicon melting temperature. Results confirm the effectiveness of this approach for increasing surface uniformity, making liquid phase processing compatible with standard device fabrication techniques.

  5. Design of multilamp nonimaging laser pump cavities

    SciTech Connect

    Kuppenheimer, J.D. Jr.

    1989-12-01

    A technique has been developed to design single laser rod, multiple flash lamp pump cavities that allow all of the energy generated by the lamp to pass through the laser rod before entering another lamp cavity. The effective lamp and rod perimeters are matched, guaranteeing maximal concentration and uniformity of pumping.

  6. Application of flash-lamp post-exposure baking for EUV resist processing

    NASA Astrophysics Data System (ADS)

    Kaneyama, Koji; Itani, Toshiro

    2011-04-01

    The reduction of linewidth roughness (LWR) is considered one of the most critical issues in extreme ultraviolet (EUV) photoresists. A possible solution to the LWR issue is shortening the acid-diffusion length of the photoacid via the optimized application of post-exposure bake (PEB) processes. In this study, the development and feasibility of the flash-lamp (FL) PEB process as a replacement for the commonly used hot-plate PEB process is investigated. The results indicate that, using the FL PEB process, the acid-diffusion length is controllable and lithographic patterning results are obtained. Further detailed analysis is necessary to optimize this technology for lithographic patterning applications. However, the present results show the potential of FL PEB for applications in EUV photoresist processing.

  7. Flash Lamp Integrating Sphere Technique for Measuring the Dynamic Reflectance of Shocked Materials

    SciTech Connect

    Stevens, Gerald; La Lone, Brandon; Veeser, Lynn; Hixson, Rob; Holtkamp, David

    2013-07-08

    Accurate reflectance (R) measurements of metals undergoing shock wave compression can benefit high pressure research in several ways. For example, pressure dependent reflectance measurements can be used to deduce electronic band structure, and discrete changes with pressure or temperature may indicate the occurrence of a phase boundary. Additionally, knowledge of the wavelength dependent emissivity (1 -R, for opaque samples) of the metal surface is essential for accurate pyrometric temperature measurement because the radiance is a function of both the temperature and emissivity. We have developed a method for measuring dynamic reflectance in the visible and near IR spectral regions with nanosecond response time and less than 1.5% uncertainty. The method utilizes an integrating sphere fitted with a xenon flash-lamp illumination source. Because of the integrating sphere, the measurements are insensitive to changes in surface curvature or tilt. The in-situ high brightness of the flash-lamp exceeds the sample’s thermal radiance and also enables the use of solid state detectors for recording the reflectance signals with minimal noise. Using the method, we have examined the dynamic reflectance of gallium and tin subjected to shock compression from high explosives. The results suggest significant reflectance changes across phase boundaries for both metals. We have also used the method to determine the spectral emissivity of shock compressed tin at the interface between tin and a LiF window. The results were used to perform emissivity corrections to previous pyrometry data and obtain shock temperatures of the tin/LiF interface with uncertainties of less than 2%.

  8. Analysis of a four lamp flash system for calibrating multi-junction solar cells under concentrated light

    SciTech Connect

    Schachtner, Michael Prado, Marcelo Loyo; Reichmuth, S. Kasimir; Siefer, Gerald; Bett, Andreas W.

    2015-09-28

    It has been known for a long time that the precise characterization of multi-junction solar cells demands spectrally tunable solar simulators. The calibration of innovative multi-junction solar cells for CPV applications now requires tunable solar simulators which provide high irradiation levels. This paper describes the commissioning and calibration of a flash-based four-lamp simulator to be used for the measurement of multi-junction solar cells with up to four subcells under concentrated light.

  9. Nonconventional Use of Flash-Lamp Pulsed-Dye Laser in Dermatology

    PubMed Central

    Del Duca, Ester; Bruscino, Nicola; Conti, Rossana; Cannarozzo, Giovanni

    2016-01-01

    Flash-lamp pulsed-dye laser (FPDL) is a nonablative technology, typically used in vascular malformation therapy due to its specificity for hemoglobin. FPDL treatments were performed in a large group of patients with persistent and/or recalcitrant different dermatological lesions with cutaneous microvessel involvement. In particular, 149 patients (73 males and 76 females) were treated. They were affected by the following dermatological disorders: angiokeratoma circumscriptum, genital and extragenital viral warts, striae rubrae, basal cell carcinoma, Kaposi's sarcoma, angiolymphoid hyperplasia, and Jessner-Kanof disease. They all underwent various laser sessions. 89 patients (59.7%) achieved excellent clearance, 32 patients (21.4%) achieved good-moderate clearance, 19 patients (12.7%) obtained slight clearance, and 9 subjects (6.1%) had low or no removal of their lesion. In all cases, FPDL was found to be a safe and effective treatment for the abovementioned dermatological lesions in which skin microvessels play a role in pathogenesis or development. Further and single-indication studies, however, are required to assess a standardized and reproducible method for applying this technology to “off-label” indications.

  10. Blackbody absorption efficiencies for six lamp pumped Nd laser materials.

    PubMed

    Cross, P L; Barnes, N P; Skolaut, M W; Storm, M E

    1990-02-20

    Utilizing high resolution spectra, the absorption efficiency for six Nd laser materials was calculated as functions of the effective blackbody temperature of the lamp and laser crystal size. The six materials were Nd:YAG, Nd:YLF, Nd:Q-98 Glass, Nd:YVO(4), Nd:BEL, and Nd:Cr:GSGG. Under the guidelines of this study, Nd:Cr:GSGG's absorption efficiency is twice the absorption efficiency of any of the other laser materials. PMID:20556185

  11. Blackbody absorption efficiencies for six lamp pumped Nd laser materials

    NASA Technical Reports Server (NTRS)

    Cross, Patricia L.; Barnes, Norman P.; Skolaut, Milton W., Jr.; Storm, Mark E.

    1990-01-01

    Utilizing high resolution spectra, the absorption efficiencies for six Nd laser materials were calculated as functions of the effective blackbody temperature of the lamp and laser crystal size. The six materials were Nd:YAG, Nd:YLF, Nd:Q-98 Glass, Nd:YVO4, Nd:BEL, and Nd:Cr:GSGG. Under the guidelines of this study, Nd:Cr:GSGG's absorption efficiency is twice the absorption efficiency of any of the other laser materials.

  12. Boron activation and diffusion in silicon and strained silicon-on-insulator by rapid thermal and flash lamp annealings

    NASA Astrophysics Data System (ADS)

    Lanzerath, F.; Buca, D.; Trinkaus, H.; Goryll, M.; Mantl, S.; Knoch, J.; Breuer, U.; Skorupa, W.; Ghyselen, B.

    2008-08-01

    We present experimental results on the activation and diffusion behaviors of boron in silicon-on-insulator and strained silicon-on-insulator using standard rapid thermal processing treatments as well as flash lamp annealing. After boron implantation at different doses and at a low energy of 1 keV, samples were annealed to activate the dopants, and secondary ion mass spectrometry and Hall measurements were carried out to determine boron diffusion and the amount of activated dopants, respectively. In contrast to rapid thermal annealing, flash lamp annealing enables the activation without significant diffusion of dopants. In addition, we investigated the effect of coating the samples with antireflection layers to increase the absorbed energy during flash annealing. As a result, the activation was increased significantly to values comparable with the activation obtained with standard annealing. Furthermore, the relation between the observed boron diffusion and activation as a function of the implantation and annealing parameters is discussed in terms of the kinetics of the defects involved in these processes.

  13. Active lamp pulse driver circuit. [optical pumping of laser media

    NASA Technical Reports Server (NTRS)

    Logan, K. E. (Inventor)

    1983-01-01

    A flashlamp drive circuit is described which uses an unsaturated transistor as a current mode switch to periodically subject a partially ionized gaseous laser excitation flashlamp to a stable, rectangular pulse of current from an incomplete discharge of an energy storage capacitor. A monostable multivibrator sets the pulse interval, initiating the pulse in response to a flash command by providing a reference voltage to a non-inverting terminal of a base drive amplifier; a tap on an emitter resistor provides a feedback signal sensitive to the current amplitude to an inverting terminal of amplifier, thereby controlling the pulse amplitude. The circuit drives the flashlamp to provide a squarewave current flashlamp discharge.

  14. Lamp pumped Nd:YAG laser. Space-qualifiable Nd:YAG laser for optical communications

    NASA Technical Reports Server (NTRS)

    Ward, K. B.

    1973-01-01

    Results are given of a program concerned with the design, fabrication, and evaluation of alkali pump lamps for eventual use in a space qualified Nd:YAG laser system. The study included evaluation of 2mm through 6mm bore devices. Primary emphasis was placed upon the optimization of the 4mm bore lamp and later on the 6mm bore lamp. As part of this effort, reference was made to the Sylvania work concerned with the theoretical modeling of the Nd:YAG laser. With the knowledge gained, a projection of laser performance was made based upon realistic lamp parameters which should easily be achieved during following developmental efforts. Measurements were made on the lamp performance both in and out of the cavity configuration. One significant observation was that for a constant vapor pressure device, the spectral and fluorescent output did not vary for vacuum or argon environment. Therefore, the laser can be operated in an inert environment (eg. argon) with no degradation in output. Laser output of 3.26 watts at 430 watts input was obtained for an optimized 4mm bore lamp.

  15. Implantation-caused open volume defects in Ge after flash lamp annealing (FLA) probed by slow positron implantation spectroscopy (SPIS)

    NASA Astrophysics Data System (ADS)

    Anwand, W.; Skorupa, W.; Schumann, Th.; Posselt, M.; Schmidt, B.; Grötzschel, R.; Brauer, G.

    2008-10-01

    B + and P + ions were implanted into Ge wafers covered with a pre-amorphised surface layer of 150 nm. After this, flash lamp annealing (FLA) in Ar atmosphere was used as post-implantation heat treatment. Radiation with Xenon flash lamps, having a spectrum in the visible range of light and a pulse length of 3 ms or 20 ms, allowed an ultra-short heating up of the near surface region. In this way, a modification of the structure of the as-implanted amorphous Ge layer was possible. Depth profiles of defects, especially those of the vacancy-type, were investigated by slow positron implantation spectroscopy (SPIS) before and after FLA. It was found that the remaining vacancy-type defect structure depends on the parameters of the process of heat treatment, and that these defects could not be completely removed by FLA. Results are compared with such from SRIM 2006 calculations (stopping and range of ions in matter) and Rutherford backscattering spectrometry (RBS).

  16. 49 CFR 393.25 - Requirements for lamps other than head lamps.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... lamps; school bus warning lamps; amber warning lamps or flashing warning lamps on tow trucks and... are not required to be steady burning while the turn signal is in use. Amber warning lamps must meet.... Amber flashing warning lamps must meet SAE J595—Directional Flashing Optical Warning Devices...

  17. 49 CFR 393.25 - Requirements for lamps other than head lamps.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... lamps; school bus warning lamps; amber warning lamps or flashing warning lamps on tow trucks and... are not required to be steady burning while the turn signal is in use. Amber warning lamps must meet.... Amber flashing warning lamps must meet SAE J595—Directional Flashing Optical Warning Devices...

  18. Formation of shallow boron emitters in crystalline silicon using flash lamp annealing: Role of excess silicon interstitials

    SciTech Connect

    Riise, Heine Nygard Azarov, Alexander; Svensson, Bengt G.; Monakhov, Edouard

    2015-07-13

    Shallow, Boron (B)-doped p{sup +} emitters have been realized using spin-on deposition and Flash Lamp Annealing (FLA) to diffuse B into monocrystalline float zone Silicon (Si). The emitters extend between 50 and 140 nm in depth below the surface, have peak concentrations between 9 × 10{sup 19 }cm{sup –3} and 3 × 10{sup 20 }cm{sup –3}, and exhibit sheet resistances between 70 and 3000 Ω/□. An exceptionally large increase in B diffusion occurs for FLA energy densities exceeding ∼93 J/cm{sup 2} irrespective of 10 or 20 ms pulse duration. The effect is attributed to enhanced diffusion of B caused by Si interstitial injection following a thermally activated reaction between the spin-on diffusant film and the silicon wafer.

  19. Femtosecond-precision synchronization of the pump-probe optical laser for user experiments at FLASH

    NASA Astrophysics Data System (ADS)

    Schulz, S.; Czwalinna, M. K.; Felber, M.; Predki, P.; Schefer, S.; Schlarb, H.; Wegner, U.

    2013-05-01

    In this paper, we present the long-term stable synchronization of the FLASH pump-probe Ti:sapphire oscillator to an optical reference with sub-10 fs (rms) timing jitter employing a balanced optical cross-correlator. The reference pulse train, transmitted over an actively transit time-stabilized 500m long fiber link, is generated by the FLASH master laser oscillator. This laser also provides the reference for several electron bunch arrival time monitors with sub-10 fs resolution, which in turn enables a longitudinal feedback reducing the electron bunch arrival time jitter to below 25 fs (rms). Combining the precise synchronization of the laser and the longitudinal accelerator feedback enabled a proof-of-principle pump-probe experiment at FLASH, ultimately showing a significant reduction of the timing jitter between the optical laser and the XUV pulses generated by the FEL, compared to the present standard operation.

  20. Oxygen uptake occurs faster than sodium pumping in bee retina after a light flash.

    PubMed

    Tsacopoulos, M; Orkand, R K; Coles, J A; Levy, S; Poitry, S

    When neurones are active there is an entry of Na+, which must subsequently be pumped out, and an increase in their oxygen consumption rate (Qo2). The Na+ pump derives its energy from ATP, splitting it into ADP and Pi, and it has reasonably been proposed that the changes in concentrations of ATP, ADP and Pi lead to a stimulation of the O2 consumption by the mitochondria and hence to a restoration of the stock of ATP. Here we present evidence suggesting that Qo2 must be controlled differently in the retinal photoreceptor cells of the honeybee drone. Stimulation of drone photoreceptors with a flash of light causes an entry of Na+ (ref. 4) and a transient increase in Qo2 that indicates respiration of the right order of magnitude to provide ATP to pump the Na+ out. We report intracellular recordings of changes in intracellular sodium (Nai+) and potassium (Ki+) in response to single light flashes and have compared the time course of extra oxygen consumption (delta Qo2) with these ion changes and other indices of Na+ pumping. We found that the time course of pumping seems to lag behind the time course of delta Qo2. It follows that the mitochondrial respiration must be stimulated by some signal which is generated earlier than the rise in ADP produced by the Na+ pump. PMID:6828139

  1. Reliability characteristics of microfabricated Rb mini-lamps for optical pumping in miniature atomic clocks and magnetometers

    NASA Astrophysics Data System (ADS)

    Venkatraman, Vinu; Pétremand, Yves; de Rooij, Nico; Shea, Herbert

    2013-03-01

    With the rising need for microfabricated chip-scale atomic clocks to enable high precision timekeeping in portable applications, there has been active interest in developing miniature (lamps, since vapor plasma discharge sources are currently the standard for optical pumping in double-resonance clocks. We reported in 2012 a first microfabricated chip-scale Rubidium dielectric barrier discharge lamp. The device's preliminary results indicated its high potential for optical pumping applications and wafer-scale batch fabrication. The chip-scale plasma light sources were observed to be robust with no obvious performance change after thousands of plasma ignitions, and with no electrode erosion from plasma discharges since the electrodes are external. However, as atomic clocks have strict lamp performance requirements including less than 0.1% sub-second optical power fluctuations, power consumption less than 20 mW and a device lifetime of at least several years, it is important to understand the long-term reliability of these Rb planar mini-lamps, and identify the operating conditions where these devices can be most reliable and stable. In this paper, we report on the reliability of such microfabricated lamps including a continuous several month run of the lamp where the optical power, electrical power consumption and temperature stability were continuously monitored. We also report on the effects of temperature, rf-power and the lamp-drive parasitics on the optical power stability and discuss steps that could be taken to further improve the device's performance and reliability.

  2. The effect of millisecond flash lamp annealing on electrical and structural properties of ZnO:Al/Si structures

    NASA Astrophysics Data System (ADS)

    Lindberg, P. F.; Lipp Bregolin, F.; Wiesenhütter, K.; Wiesenhütter, U.; Riise, H. N.; Vines, L.; Prucnal, S.; Skorupa, W.; Svensson, B. G.; Monakhov, E. V.

    2016-05-01

    The effect of millisecond flash lamp annealing (FLA) on aluminum doped ZnO (AZO) films and their interface with Si have been studied. The AZO films were deposited by magnetron sputtering on Si (100) substrates. The electrical and structural properties of the film and AZO/Si structures were characterized by current-voltage, capacitance-voltage, and deep level transient spectroscopy measurements, X-ray diffraction, and secondary ion mass spectrometry. The resistivity of the AZO film is reduced to a close to state-of-the-art value of 2 × 10-4 Ω cm after FLA for 3 ms with an average energy density of 29 J/cm2. In addition, most of the interfacial defects energy levels are simultaneously annealed out, except for one persisting shallow level, tentatively assigned to the vacancy-oxygen complex in Si, which was not affected by FLA. Subsequent to the FLA, the samples were treated in N2 or forming gas (FG) (N2/H2, 90/10%mole) ambient at 200-500 °C. The latter samples maintained the low resistivity achieved after the FLA, but not the former ones. The interfacial defect level persisting after the FLA is removed by the FG treatment, concurrently as another level emerges at ˜0.18 eV below the conduction band. The electrical data of the AZO films are discussed in term of point defects controlling the resistivity, and it is argued that the FLA promotes formation of electrically neutral clusters of Zink vacancies (VZn's) rather than passivating/compensating complexes between the Al donors and VZn's.

  3. Flash!

    NASA Astrophysics Data System (ADS)

    Schilling, Govert

    2002-04-01

    About three times a day our sky flashes with a powerful pulse of gamma ray bursts (GRB), invisible to human eyes but not to astronomers' instruments. The sources of this intense radiation are likely to be emitting, within the span of seconds or minutes, more energy than the sun will in its entire 10 billion years of life. Where these bursts originate, and how they come to have such incredible energies, is a mystery scientists have been trying to solve for three decades. The phenomenon has resisted study -- the flashes come from random directions in space and vanish without trace -- until very recently. In what could be called a cinematic conflation of Flash Gordon and The Hunt for Red October, Govert Schilling's Flash!: The Hunt for the Biggest Explosions in the Universe describes the exciting and ever-changing field of GRB research. Based on interviews with leading scientists, Flash! provides an insider's account of the scientific challenges involved in unravelling the enigmatic nature of GRBs. A science writer who has followed the drama from the very start, Schilling describes the ambition and jealousy, collegiality and competition, triumph and tragedy, that exists among those who have embarked on this recherche. Govert Schilling is a Dutch science writer and astronomy publicist. He is a contributing editor of Sky and Telescope magazine, and regularly writes for the news sections of Science and New Scientist. Schilling is the astronomy writer for de Volkskrant, one of the largest national daily newspapers in The Netherlands, and frequently talks about the Universe on Dutch radio broadcasts. He is the author of more than twenty popular astronomy books, and hundreds of newspaper and magazine articles on astronomy.

  4. Flash lamp light slicing

    NASA Astrophysics Data System (ADS)

    Saber, A. J.; Abdel-Wahab, T.; Georgallis, M.

    A light slicing system using a short-arc-length high-power flashlamp as the source is discussed, with application to the observation of fluid phenomena such as gas discharge and fuel injection into engines. The geometrical optics of the method, in addition to the attenuation of luminous intensity in the system, is considered, and varying the relative radius of curvature of the cylindrical lens with respect to the width of the laser beam is shown to change the extension of the light sheet lamina. Light slice system generation using CAD is discussed, and experimental results of the observation of pulsed gas discharges in a small scale valve system designed to simulate large-scale dispersion and mixing of gases in air are reported.

  5. Multiple pass effects in high efficiency laser pumping cavities.

    PubMed

    Evtuhov, V; Neeland, J K

    1967-03-01

    Some effects connected with multiple passes of pump radiation in laser pump cavities are discussed. These effects include changes in mercury arc lamp operating characteristics, when the lamps are used inside the cavities as pump sources, and unexpectedly low pulse (but not cw) thresholds in double elliptical cavities. It is shown analytically that these effects can, at least in part, be attributed to the shapes of the pump light energy distribution curves after multiple passes through the pump cavities, and to the relative opacities of flash and continuous lamps. PMID:20057775

  6. Formation and photoluminescence of GaAs{sub 1−x}N{sub x} dilute nitride achieved by N-implantation and flash lamp annealing

    SciTech Connect

    Gao, Kun Helm, M.; Prucnal, S.; Skorupa, W.; Zhou, Shengqiang

    2014-07-07

    In this paper, we present the fabrication of dilute nitride semiconductor GaAs{sub 1−x}N{sub x} by nitrogen-ion-implantation and flash lamp annealing (FLA). N was implanted into the GaAs wafers with atomic concentration of about x{sub imp1} = 0.38% and x{sub imp2} = 0.76%. The GaAs{sub 1−x}N{sub x} layer is regrown on GaAs during FLA treatment in a solid phase epitaxy process. Room temperature near band-edge photoluminescence (PL) has been observed from the FLA treated GaAs{sub 1−x}N{sub x} samples. According to the redshift of the near band-edge PL peak, up to 80% and 44% of the implanted N atoms have been incorporated into the lattice by FLA for x{sub imp1} = 0.38% and x{sub imp2} = 0.76%, respectively. Our investigation shows that ion implantation followed by ultrashort flash lamp treatment, which allows for large scale production, exhibits a promising prospect on bandgap engineering of GaAs based semiconductors.

  7. A high efficiency all-PMOS charge pump for 3D NAND flash memory

    NASA Astrophysics Data System (ADS)

    Liyin, Fu; Yu, Wang; Qi, Wang; Zongliang, Huo

    2016-07-01

    For 3D vertical NAND flash memory, the charge pump output load is much larger than that of the planar NAND, resulting in the performance degradation of the conventional Dickson charge pump. Therefore, a novel all PMOS charge pump with high voltage boosting efficiency, large driving capability and high power efficiency for 3D V-NAND has been proposed. In this circuit, the Pelliconi structure is used to enhance the driving capability, two auxiliary substrate bias PMOS transistors are added to mitigate the body effect, and the degradation of the output voltage and boost efficiency caused by the threshold voltage drop is eliminated by dynamic gate control structure. Simulated results show that the proposed charge pump circuit can achieve the maximum boost efficiency of 86% and power efficiency of 50%. The output voltage of the proposed 9 stages charge pump can exceed 2 V under 2 MHz clock frequency in 2X nm 3D V-NAND technology. Our results provide guidance for the peripheral circuit design of high density 3D V-NAND integration.

  8. Passive apparatus for stabilizing a flashlamp-pumped dye laser

    SciTech Connect

    De Wilde, M.A.; Decker, L.J.

    1986-04-29

    A flash lamp pumped, dye laser apparatus is described which consists of a flash lamp and a liquid dye solution in a transparent compartment proximate to the flash lamp. The compartment is also connected to a tubular circulatory system for moving the liquid dye. The dye solution is activated by flashing of the lamp for lasing to emit light, the lamp and compartment enclosed in a cooling first water jacket, the jacket enclosing deionized water for cooling, an improved cooling system wherein the temperature of the deionized water and the liquid dye solution are maintained within 0.5/sup 0/C of one another, enabling the laser for pulsing at a stabilized 10 pulses per second rate.

  9. Deflagration-induced flash of solid pyrotechnics as pumps for high-energy solid state lasers

    NASA Astrophysics Data System (ADS)

    Kang, Xiaoli; Liu, Liming; Tang, Yongjian

    2013-09-01

    Using the flash produced by deflagration of solid pyrotechnics to pump the laser gain medium is a potentially effective way to develop portable high power lasers. The purpose of this work is to examine the effect of some optimization or modifications in terms of compositions and distribution of the pyrotechnic pumping sources on the laser output. The optimization means the transmittance of the output couple. Modifications include: (1) pyrotechnic compositions are improved by adding small amounts of nano Al powders; (2) distribution of pumping light around the laser rod is changed through changing the discrete pyrotechnic tablets into continuous pyrotechnic bars. Results showed that laser output energy reached the maximum of 656 mJ when the transmittance of output mirror raised to10%; after adding nano Al powders into pyrotechnic compositions, laser energy increased by 80% at addition of 2% in the case of discrete distribution, while in the case of continuous distribution, even the mass of pyrotechnics was halved, laser energy still increased to the maximum of 442 mJ with 1% nano Al added. Besides, typical temporal waveform and spot of the laser as well as the light radiation performance of the pyrotechnic tablet are measured to help analyze the laser output performance. It is suggested that the mechanisms of the three modifications we employed are different though they all lead to increase in laser output.

  10. Development of a lamp-pumped Cr:LiSAF laser operating at 20Hz for a terawatt CPA system

    NASA Astrophysics Data System (ADS)

    Samad, Ricardo E.; Nogueira, Gesse E. C.; Baldochi, Sonia L.; Vieira, Nilson D., Jr.

    2006-02-01

    We report here the development, construction and characterization of a flashlamp pumped Cr:LiSAF rod pumping cavity designed to minimize the thermal load on the crystal. The cavity is a close coupled one with 2 Xe lamps and absorptive filters between the lamps and the Cr:LiSAF rod, and is refrigerated with cooled water. A compact and stable (g I×g II=0.57) resonator was designed for lasers tests and gain medium characterization, and we expected to obtain operation at 20 Hz repetition rate. Nevertheless, the thermal load minimizing design was so successful that allowed laser operation up to 30 Hz with an average power of 20 W. When operating with a 10% transmission output coupler this laser exhibited an overall laser efficiency of 0.6% under 100 J electrical pumping, and a slope efficiency of 0.8%. Under these conditions, a maximum gain per pass of 1.5 was obtained, suitable for regenerative amplifiers. To increase the gain, the intracavity filters were substituted by glass plates, resulting in a gain per pass of 3.6, adequate for multipass amplifiers. In this configuration, and operating as a laser resonator, it showed a maximum overall efficiency of 2.81% under 88 J electrical pumping with a 25% transmission output coupler, and maximum output power of 18 W at 8 Hz. A study of the thermal load on the crystal was conducted by observation of the upper laser level lifetime, and we concluded that there are no noticeable accumulated thermal effects on the Cr:LiSAF emission.

  11. 2.3-ps pulses from a Kerr-lens mode-locked lamp-pumped Nd:YLF laser with a microdot mirror.

    PubMed

    Ramaswamy, M; Gouveia-Neto, A S; Negus, D K; Izatt, J A; Fujimoto, J G

    1993-11-01

    Pulses as short as 2.3 ps have been generated by passive mode locking of a lamp-pumped Nd:YLF laser with a microdot mirror mode locker for Kerr-lens mode-locking (KLM) saturable absorber action and a compact Gires-Tournois interferometer for dispersion compensation. KLM was initiated with an acousto-optic modulator. Average output powers of 800 mW have been achieved. This result demonstrates the potential use of KLM for generating near-bandwidth-limited pulses from high-power lamp-pumped sources. PMID:19829417

  12. Atomic-fluorescence analysis of materials using a lamp-pumped dye LZhI laser as an excitation source

    SciTech Connect

    Denisov, L.K.; Loshin, A.F.; Nikiforov, V.G.; Sterlyadkina, E.A.

    1987-12-01

    The use of frequency-tunable dye lasers in atomic-fluorescence analysis has made it possible to lower significantly the limits of detection for most elements. In this work the commercially produced lamp-pumped dye lasers of the type LZhI were used as the excitation source, which made it possible, first of all, to simplify the design of the atomic-fluorescence spectrometer by eliminating the frequency doubling of the laser radiation and, second, to study the analytical possibilities of commercially produced dye lasers with microsecond lasing. The authors studied solutions of sodium, barium, potassium, calcium, nickel, cobalt, copper, and molybdenum salts. These elements were chosen based on the fact that they have absorption lines with different degrees of intensity in the region of generation of the most efficient rhodamine 6G dye laser.

  13. Novel Pb(Ti, Zr)O3(PZT) Crystallization Technique Using Flash Lamp for Ferroelectric RAM (FeRAM) Embedded LSIs and One Transistor Type FeRAM Devices

    NASA Astrophysics Data System (ADS)

    Yamakawa, Koji; Imai, Keitaro; Arisumi, Osamu; Arikado, Tsunetoshi; Yoshioka, Masaki; Owada, Tatsushi; Okumura, Katsuya

    2002-04-01

    A novel method of ferroelectric capacitor formation for Ferroelectrie random access memory (FeRAM) embedded LSIs and one-transistor-type FeRAMs has been developed. Amorphous Pb(Ti, Zr)O3(PZT) films were successfully transformed to the perovskite phase by a flash lamp technique with a crystallization time of 1.2 ms at a substrate temperature of 350°C. A flash lamp energy of 27 J/cm2 was sufficient to form a ferroelectric crystal structure due to rapid thermal effects with little heat diffusion in the depth direction. This technique enabled PZT film crystallization in Pt/PZT/Pt structures on multi-Al wiring layers. Granular PZT grains were observed on Pt, Ru and RuO2 electrodes, which indicates that crystal growth begins from the film surfaces. Ferroelectric property was verified by the process at 350°C maximum temperature. PZT films were also crystallized directly on SiO2. This is useful for the fabrication of embedded FeRAM devices and 1Tr-type FeRAMs. The flash lamp process was found to have great potential for application to dielectric film formation, annealing processes and so on.

  14. Liquid phase epitaxy of binary III–V nanocrystals in thin Si layers triggered by ion implantation and flash lamp annealing

    SciTech Connect

    Wutzler, Rene Rebohle, Lars; Prucnal, Slawomir; Bregolin, Felipe L.; Hübner, Rene; Voelskow, Matthias; Helm, Manfred; Skorupa, Wolfgang

    2015-05-07

    The integration of III–V compound semiconductors in Si is a crucial step towards faster and smaller devices in future technologies. In this work, we investigate the formation process of III–V compound semiconductor nanocrystals, namely, GaAs, GaSb, and InP, by ion implantation and sub-second flash lamp annealing in a SiO{sub 2}/Si/SiO{sub 2} layer stack on Si grown by plasma-enhanced chemical vapor deposition. Raman spectroscopy, Rutherford Backscattering spectrometry, and transmission electron microscopy were performed to identify the structural and optical properties of these structures. Raman spectra of the nanocomposites show typical phonon modes of the compound semiconductors. The formation process of the III–V compounds is found to be based on liquid phase epitaxy, and the model is extended to the case of an amorphous matrix without an epitaxial template from a Si substrate. It is shown that the particular segregation and diffusion coefficients of the implanted group-III and group-V ions in molten Si significantly determine the final appearance of the nanostructure and thus their suitability for potential applications.

  15. Liquid phase epitaxy of binary III-V nanocrystals in thin Si layers triggered by ion implantation and flash lamp annealing

    NASA Astrophysics Data System (ADS)

    Wutzler, Rene; Rebohle, Lars; Prucnal, Slawomir; Bregolin, Felipe L.; Hübner, Rene; Voelskow, Matthias; Helm, Manfred; Skorupa, Wolfgang

    2015-05-01

    The integration of III-V compound semiconductors in Si is a crucial step towards faster and smaller devices in future technologies. In this work, we investigate the formation process of III-V compound semiconductor nanocrystals, namely, GaAs, GaSb, and InP, by ion implantation and sub-second flash lamp annealing in a SiO2/Si/SiO2 layer stack on Si grown by plasma-enhanced chemical vapor deposition. Raman spectroscopy, Rutherford Backscattering spectrometry, and transmission electron microscopy were performed to identify the structural and optical properties of these structures. Raman spectra of the nanocomposites show typical phonon modes of the compound semiconductors. The formation process of the III-V compounds is found to be based on liquid phase epitaxy, and the model is extended to the case of an amorphous matrix without an epitaxial template from a Si substrate. It is shown that the particular segregation and diffusion coefficients of the implanted group-III and group-V ions in molten Si significantly determine the final appearance of the nanostructure and thus their suitability for potential applications.

  16. Treatment of Port-Wine Stains with Flash Lamp Pumped Pulsed Dye Laser on Indian Skin: A Six Year Study

    PubMed Central

    Thajudheen, Chandroth Ponnambath; Jyothy, Kannangath; Priyadarshini, Arul

    2014-01-01

    Context: Port-wine stain (PWS) is one of the commonly encountered congenital cutaneous vascular lesions, with an equal sex distribution. Pulsed dye lasers (PDL) have revolutionized the treatment of both congential and acquired cutaneous vascular lesions. The pulsed dye lasers owing to its superior efficacy and safety profile have become the gold standard for the management of port-wine stains. Aims: To evaluate the efficacy and side effects of pulsed dye laser for the management of Port-wine stain on Indian skin. Materials and Methods: Seventy five patients of Fitzpatrick skin types IV&V with PWS underwent multiple treatments with PDL (V beam-Candela) over a period of six years at monthly intervals. Laser parameters were wavelength 595nm, spot sizes 7-10mm, fluence 6-12 j/cm2, pulse duration 0.45-10ms, along with cryogen cooling. Serial photographs were taken before and after every session. Clinical improvement scores of comparable photographs using a quartile grading (o=<20%, 1=21-40%, 2=41-60%, 3=61-80%, 4=>80%) were judged independently by two dermatologists after the series of treatment. Minimum number of treatments was 6 and maximum 17. They were followed up at six monthly intervals to observe re darkening of PWS. Results: No patient showed total clearance.Grade3 improvement was observed in 70 % of children and 50% of adults after 8-10 sessions. Children showed better and faster response than adults. Thirty percent of patients developed post inflammatory hyper pigmentation which resolved over a period of six to eight weeks. Two patients had superficial scarring due to stacking of pulses. None of the patients showed re darkening of PWS till now. Conclusion: Pulsed dye laser is an effective and safe treatment for port-wine stain in Indian skin. PMID:24761097

  17. Investigating two-photon double ionization of D2 by XUV-Pump -- XUV-Probe experiments at FLASH

    SciTech Connect

    FLASH Collaboration; Jiang, Y.; Rudenko, A.; Perez-Torres, J.; Foucar, L.; Kurka, M.; Kuhnel, K.; Toppin, M.; Plesiat, E.; Morales, F.; Martin, F.; Herrwerth, O.; Lezius, M.; Kling, M.; Jahnke, T.; Dorner, R.; Sanz-Vicario, J.; van Tilborg, J.; Belkacem, A.; Schulz, M.; Ueda, K.; Zouros, T.; Dusterer, S.; Treusch, R.; Schroter, C.; Moshammer, R.; Ullrich, J.

    2010-08-02

    Using a novel split-mirror set-up attached to a Reaction Microscope at the Free electron LASer in Hamburg (FLASH) we demonstrate an XUV-pump -- XUV-probe ((hbar omega = 38 eV) experiment by tracing the ultra-fast nuclear wave-packet motion in the D2+ (1s sigma g-state) with<10 fs time resolution. Comparison with time-dependent calculations yields excellent agreement with the measured vibrational period of 22+-4 fs in D2+, points to the importance of the inter-nuclear distance dependent ionization probability and paves the way to control sequential and non-sequential two-photon double ionization contributions.

  18. Mode locking of diode- and flashlamp-pumped Nd:YAG lasers using semiconductor saturable absorbers

    NASA Astrophysics Data System (ADS)

    Dombrovsky, Andrej; Kubecek, Vaclav; Zvonicek, K.; Diels, Jean-Claude M.; Stintz, Andreas

    2003-07-01

    Operation of laser diode and flash lamp pumped Nd:YAG lasers mode locked with two different types of semiconductor saturable absorbers is reported. In the first type that is used mainly in diode pumped systems the absorber layers are integrated on highly reflective Bragg mirror. The second type is for use in transmission mode inside the resonator. Different design of semiconductor elements, pumping geometries and resonator configurations were investigated and characteristics of laser operation in mode-locked regime are presented.

  19. The optical pumping of alkali atoms using coherent radiation from semi-conductor injection lasers and incoherent radiation from resonance lamps

    NASA Technical Reports Server (NTRS)

    Singh, G.

    1973-01-01

    An experimental study for creating population differences in the ground states of alkali atoms (Cesium 133) is presented. Studies made on GaAs-junction lasers and the achievement of population inversions among the hyperfine levels in the ground state of Cs 133 by optically pumping it with radiation from a GaAs diode laser. Laser output was used to monitor the populations in the ground state hyperfine levels as well as to perform the hyperfine pumping. A GaAs laser operated at about 77 K was used to scan the 8521 A line of Cs 133. Experiments were performed both with neon-filled and with paraflint-coated cells containing the cesium vapor. Investigations were also made for the development of the triple resonance coherent pulse technique and for the detection of microwave induced hyperfine trasistions by destroying the phase relationships produced by a radio frequency pulse. A pulsed cesium resonance lamp developed, and the lamp showed clean and reproducible switching characteristics.

  20. Analysis of the energy distribution of interface traps related to tunnel oxide degradation using charge pumping techniques for 3D NAND flash applications

    SciTech Connect

    An, Ho-Myoung; Kim, Hee-Dong; Kim, Tae Geun

    2013-12-15

    Graphical abstract: The degradation tendency extracted by CP technique was almost the same in both the bulk-type and TFT-type cells. - Highlights: • D{sub it} is directly investigated from bulk-type and TFT-type CTF memory. • Charge pumping technique was employed to analyze the D{sub it} information. • To apply the CP technique to monitor the reliability of the 3D NAND flash. - Abstract: The energy distribution and density of interface traps (D{sub it}) are directly investigated from bulk-type and thin-film transistor (TFT)-type charge trap flash memory cells with tunnel oxide degradation, under program/erase (P/E) cycling using a charge pumping (CP) technique, in view of application in a 3-demension stackable NAND flash memory cell. After P/E cycling in bulk-type devices, the interface trap density gradually increased from 1.55 × 10{sup 12} cm{sup −2} eV{sup −1} to 3.66 × 10{sup 13} cm{sup −2} eV{sup −1} due to tunnel oxide damage, which was consistent with the subthreshold swing and transconductance degradation after P/E cycling. Its distribution moved toward shallow energy levels with increasing cycling numbers, which coincided with the decay rate degradation with short-term retention time. The tendency extracted with the CP technique for D{sub it} of the TFT-type cells was similar to those of bulk-type cells.

  1. Flickering lamps

    NASA Astrophysics Data System (ADS)

    Vollmer, Michael; Möllmann, Klaus-Peter

    2015-05-01

    Many processes in electromagnetism vary with time. Some of them are well known, in particular those related to line frequencies of 50 Hz or 60 Hz such as fluctuating light output of discharge and incandescent lamps. The flickers of discharge and incandescent lamps have quite different physical principles involved, which are investigated experimentally using high-speed cameras and theoretically using simplified models. The topic is related to other phenomena such as the transient behaviour of phosphor layers covering the screen of oscilloscopes and the time-varying Lorentz force acting on the filament of light bulbs. All studies are well suited for teaching selected aspects of electromagnetism and light at undergraduate level at university.

  2. Lava Lamp

    ERIC Educational Resources Information Center

    Leif, Todd R.

    2008-01-01

    This past semester I brought a Lava Lite[R] Lamp into my classroom. Why bring such a thing into class? Many of today's students are part of the "retro" movement. They buy clothes from the '60s, they wear their hair like people did in the '60s, and they look for the ideals and themes related to living in the 1960s. Physics education reform is also…

  3. Probing with randomly interleaved pulse train bridges the gap between ultrafast pump-probe and nanosecond flash photolysis.

    PubMed

    Nakagawa, Tatsuo; Okamoto, Kido; Hanada, Hiroaki; Katoh, Ryuzi

    2016-04-01

    Despite the long-standing importance of transient absorption (TA) spectroscopy, many researchers remain frustrated by the difficulty of measuring the nanosecond range in a wide spectral range. To address this shortcoming, we propose a TA spectrophotometer in which there is no synchronization between a pump pulse and a train of multiple probe pulses from a picosecond supercontinuum light source, termed the randomly-interleaved-pulse-train (RIPT) method. For each pump pulse, many monochromatized probe pulses impinge upon the sample, and the associated pump-probe time delays are determined passively shot by shot with subnanosecond accuracy. By repeatedly pumping with automatically varying time delays, a TA temporal profile that covers a wide dynamic range from subnanosecond to milliseconds is simultaneously obtained. By scanning wavelength, this single, simple apparatus acquires not only wide time range TA profiles, but also broadband TA spectra from the visible through the near-infrared regions. Furthermore, we present a typical result to demonstrate how the RIPT method may be used to correct for fluorescence, which often pollutes TA curves. PMID:27192271

  4. Aperture lamp

    DOEpatents

    MacLennan, Donald A.; Turner, Brian P.

    2003-01-01

    A discharge lamp includes means for containing a light emitting fill, the fill being capable of absorbing light at one wavelength and re-emitting the light at a different wavelength, the light emitted from the fill having a first spectral power distribution in the absence of reflection of light back into the fill; means for exciting the fill to cause the fill to emit light; and means for reflecting some of the light emitted by the fill back into the fill while allowing some light to exit, the exiting light having a second spectral power distribution with proportionately more light in the visible region as compared to the first spectral power distribution, wherein the light re-emitted by the fill is shifted in wavelength with respect to the absorbed light and the magnitude of the shift is in relation to an effective optical path length. Another discharge lamp includes an envelope; a fill which emits light when excited disposed in the envelope; a source of excitation power coupled to the fill to excite the fill and cause the fill to emit light; and a reflective ceramic structure disposed around the envelope and defining an light emitting opening, wherein the structure comprises a sintered body built up directly on the envelope and made from a combination of alumina and silica.

  5. Lava Lamp

    NASA Astrophysics Data System (ADS)

    Leif, Todd R.

    2008-04-01

    This past semester I brought a Lava Lite® Lamp into my classroom. Why bring such a thing into class? Many of today's students are part of the "retro" movement. They buy clothes from the '60s, they wear their hair like people did in the '60s, and they look for the ideals and themes related to living in the 1960s. Physics education reform is also examining ideas from the "retro" world of science. This was the post-Sputnik era, a time when science was done by actually doing it and not necessarily by lecturing about it. Cliff Swartz, former TPT editor, once mentioned during a presentation at a Texas AAPT meeting, "The world of physics teaching is cyclic, like a swinging pendulum. We as physics teachers jump from `new ideas' back to our old ones, each generation testing what works best for them."

  6. LED lamp

    SciTech Connect

    Galvez, Miguel; Grossman, Kenneth; Betts, David

    2013-11-12

    There is herein described a lamp for providing white light comprising a plurality of light sources positioned on a substrate. Each of said light sources comprises a blue light emitting diode (LED) and a dome that substantially covers said LED. A first portion of said blue light from said LEDs is transmitted through said domes and a second portion of said blue light is converted into a red light by a first phosphor contained in said domes. A cover is disposed over all of said light sources that transmits at least a portion of said red and blue light emitted by said light sources. The cover contains a second phosphor that emits a yellow light in response to said blue light. The red, blue and yellow light combining to form the white light and the white light having a color rendering index (CRI) of at least about 80.

  7. Driving lamps by induction

    NASA Technical Reports Server (NTRS)

    Laue, H. H.; Clough, L. G. (Inventor)

    1973-01-01

    An electrodeless lamp circuit with a coil surrounding a krypton lamp is driven by an RF input source. A coil surrounding a mercury lamp is tapped across the connection of the input central to the krypton-lamp coil. Each coil is connected in parallel with separate capacitors which form resonant circuits at the input frequency.

  8. PUMPS

    DOEpatents

    Thornton, J.D.

    1959-03-24

    A pump is described for conveving liquids, particure it is not advisable he apparatus. The to be submerged in the liquid to be pumped, a conduit extending from the high-velocity nozzle of the injector,and means for applying a pulsating prcesure to the surface of the liquid in the conduit, whereby the surface oscillates between positions in the conduit. During the positive half- cycle of an applied pulse liquid is forced through the high velocity nozzle or jet of the injector and operates in the manner of the well known water injector and pumps liquid from the main intake to the outlet of the injector. During the negative half-cycle of the pulse liquid flows in reverse through the jet but no reverse pumping action takes place.

  9. Precision performance lamp technology

    NASA Astrophysics Data System (ADS)

    Bell, Dean A.; Kiesa, James E.; Dean, Raymond A.

    1997-09-01

    A principal function of a lamp is to produce light output with designated spectra, intensity, and/or geometric radiation patterns. The function of a precision performance lamp is to go beyond these parameters and into the precision repeatability of performance. All lamps are not equal. There are a variety of incandescent lamps, from the vacuum incandescent indictor lamp to the precision lamp of a blood analyzer. In the past the definition of a precision lamp was described in terms of wattage, light center length (LCL), filament position, and/or spot alignment. This paper presents a new view of precision lamps through the discussion of a new segment of lamp design, which we term precision performance lamps. The definition of precision performance lamps will include (must include) the factors of a precision lamp. But what makes a precision lamp a precision performance lamp is the manner in which the design factors of amperage, mscp (mean spherical candlepower), efficacy (lumens/watt), life, not considered individually but rather considered collectively. There is a statistical bias in a precision performance lamp for each of these factors; taken individually and as a whole. When properly considered the results can be dramatic to the system design engineer, system production manage and the system end-user. It can be shown that for the lamp user, the use of precision performance lamps can translate to: (1) ease of system design, (2) simplification of electronics, (3) superior signal to noise ratios, (4) higher manufacturing yields, (5) lower system costs, (6) better product performance. The factors mentioned above are described along with their interdependent relationships. It is statistically shown how the benefits listed above are achievable. Examples are provided to illustrate how proper attention to precision performance lamp characteristics actually aid in system product design and manufacturing to build and market more, market acceptable product products in the

  10. Wood's lamp illumination (image)

    MedlinePlus

    A Wood's lamp emits ultraviolet light and can be a diagnostic aid in determining if someone has a fungal ... is an infection on the area where the Wood's lamp is illuminating, the area will fluoresce. Normally ...

  11. Wood's lamp examination

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003386.htm Wood's lamp examination To use the sharing features on this page, please enable JavaScript. A Wood's lamp examination is a test that uses ultraviolet ( ...

  12. Wood's Lamp Examination

    MedlinePlus

    ... dermatologists to assist in the diagnosis of various pigment and infectious disorders. The examination is performed in ... lamp. If a fungal or bacterial infection or pigment disorder is present, Wood's lamp examination can strengthen ...

  13. Diode laser-pumped solid-state lasers

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1988-01-01

    An evaluation is made of the consequences for solid-state lasers of novel diode laser-pumping technology. Diode laser-pumped neodymium lasers have operated at an electrical-to-optical efficiency of 10 percent in a single spatial mode, with linewidths of less than 10 kHz, and with a spectral power brightness sufficiently great to allow frequency extension by harmonic generation in nonlinear crystals; this has yielded green and blue sources of coherent radiation. Q-switched operation with kW peak powers and mode-locked operation with 10-picosec pulse widths have also been demonstrated. All-solid-state lasers at prices comparable to those of current flash-lamp-pumped laser systems are foreseen, as are power levels exceeding 1 kW, for coherent radar, global satellite sensing, and micromachining.

  14. A system for slit-lamp polaroid photography.

    PubMed

    Miller, D; Taube, J; Miller, R; Gleason, W; Babyn, P; Moon, J; Weiss, J N

    1981-05-01

    A system is described in which a SX-70, Alpha Model II, Polaroid, single lens reflex camera, and photoflash unit can be quickly and sturdily mounted to a slit lamp. Such a system can take sharp anterior segment prints of the eye at all slit-lamp magnifications, with white light and in the flourescein mode. The heart of the unit is the modification of an assembly initially designed to attach the camera to a light microscope. The small flash unit and power supply were designed specifically for slit lamp usage. Examples of "instant" photos of the anterior segment at different magnifications are presented. PMID:7266974

  15. Organic flash cycles for efficient power production

    DOEpatents

    Ho, Tony; Mao, Samuel S.; Greif, Ralph

    2016-03-15

    This disclosure provides systems, methods, and apparatus related to an Organic Flash Cycle (OFC). In one aspect, a modified OFC system includes a pump, a heat exchanger, a flash evaporator, a high pressure turbine, a throttling valve, a mixer, a low pressure turbine, and a condenser. The heat exchanger is coupled to an outlet of the pump. The flash evaporator is coupled to an outlet of the heat exchanger. The high pressure turbine is coupled to a vapor outlet of the flash evaporator. The throttling valve is coupled to a liquid outlet of the flash evaporator. The mixer is coupled to an outlet of the throttling valve and to an outlet of the high pressure turbine. The low pressure turbine is coupled to an outlet of the mixer. The condenser is coupled to an outlet of the low pressure turbine and to an inlet of the pump.

  16. Halogen lamp experiment, HALEX

    NASA Technical Reports Server (NTRS)

    Schmitt, G.; Stapelmann, J.

    1986-01-01

    The main purpose of the Halogen Lamp Experiment (HALEX) was to investigate the operation of a halogen lamp during an extended period in a microgravity environment and to prove its behavior in space. The Mirror Heating Facilities for Crystal Growth and Material Science Experiments in space relies on one or two halogen lamps as a furnace to melt the specimens. The HALEX aim is to verify: full power operation of a halogen lamp for a period of about 60 hours; achievement of about 10% of its terrestrial life span; and operation of the halogen lamp under conditions similar to furnace operation.

  17. Superoxide Flashes

    PubMed Central

    Ma, Qi; Fang, Huaqiang; Shang, Wei; Liu, Lei; Xu, Zhengshuang; Ye, Tao; Wang, Xianhua; Zheng, Ming; Chen, Quan; Cheng, Heping

    2011-01-01

    Irreversible mitochondrial permeability transition and the resultant cytochrome c release signify the commitment of a cell to apoptotic death. However, the role of transient MPT (tMPT) because of flickering opening of the mitochondrial permeability transition pore remains elusive. Here we show that tMPT and the associated superoxide flashes (i.e. tMPT/superoxide flashes) constitute early mitochondrial signals during oxidative stress-induced apoptosis. Selenite (a ROS-dependent insult) but not staurosporine (a ROS-independent insult) stimulated an early and persistent increase in tMPT/superoxide flash activity prior to mitochondrial fragmentation and a global ROS rise, independently of Bax translocation and cytochrome c release. Selectively targeting tMPT/superoxide flash activity by manipulating cyclophilin D expression or scavenging mitochondrial ROS markedly impacted the progression of selenite-induced apoptosis while exerting little effect on the global ROS response. Furthermore, the tMPT/superoxide flash served as a convergence point for pro- and anti-apoptotic regulation mediated by cyclophilin D and Bcl-2 proteins. These results indicate that tMPT/superoxide flashes act as early mitochondrial signals mediating the apoptotic response during oxidative stress, and provide the first demonstration of highly efficacious local mitochondrial ROS signaling in deciding cell fate. PMID:21659534

  18. Determination of the rate constants of molecular processes regulating the level of induced absorption in a laser based on an aqueous-micellar solution of rhodamine 6G with lamp pumping

    SciTech Connect

    Levin, M.B.; Snegov, M.I.; Cherkasov, A.S.

    1987-03-01

    A method of determining the average lifetime tau of the products responsible for inverse induced absorption in aqueous--micellar solutions of rhodamine 6G (R6G) on lamp pumping based on a comparison of threshold intensities of excitation (W/sub th/) in the resonators of a laser with a different Q is proposed. Using the value of tau found (0.2 ..mu..sec) and experimental data on the change in W/sub th/ with the concentration of cyclooctatetraene (COT) added to the solution the rate constant of quenching of the absorbing products by COT molecules (K/sub q/ = 2.6 x 10/sup 7/ M/sup -1/sec/sup -1/) was determined. In the assumption that the absorbing products are triplet dye molecules, the value of the rate constant of interconversion (K/sub 32/) of R6G into an aqueous--micellar solution (K/sub 32/ = 1.3 x 10/sup 7/ sec/sup -1/) was determined. A comparison was made of the values of the constants found with the corresponding values known from the literature.

  19. Discharge lamp technologies

    NASA Technical Reports Server (NTRS)

    Dakin, James

    1994-01-01

    This talk is an overview of discharge lamp technology commonly employed in general lighting, with emphasis on issues pertinent to lighting for plant growth. Since the audience is primarily from the plant growth community, and this begins the light source part of the program, we will start with a brief description of the discharge lamps. Challenges of economics and of thermal management make lamp efficiency a prime concern in controlled environment agriculture, so we will emphasize science considerations relating to discharge lamp efficiency. We will then look at the spectra and ratings of some representative lighting products, and conclude with a discussion of technological advances.

  20. Atomic Oxygen Lamp Cleaning Facility Fabricated and Tested

    NASA Technical Reports Server (NTRS)

    Sechkar, Edward A.; Stueber, Thomas J.

    1999-01-01

    NASA Lewis Research Center's Atomic Oxygen Lamp Cleaning Facility was designed to produce an atomic oxygen plasma within a metal halide lamp to remove carbon-based contamination. It is believed that these contaminants contribute to the high failure rate realized during the production of these lamps. The facility is designed to evacuate a metal halide lamp and produce a radio frequency generated atomic oxygen plasma within it. Oxygen gas, with a purity of 0.9999 percent and in the pressure range of 150 to 250 mtorr, is used in the lamp for plasma generation while the lamp is being cleaned. After cleaning is complete, the lamp can be backfilled with 0.9999-percent pure nitrogen and torch sealed. The facility comprises various vacuum components connected to a radiation-shielded box that encloses the bulb during operation. Radiofrequency power is applied to the two parallel plates of a capacitor, which are on either side of the lamp. The vacuum pump used, a Leybold Trivac Type D4B, has a pumping speed of 4-m3/hr, has an ultimate pressure of <8x10-4, and is specially adapted for pure oxygen service. The electronic power supply, matching network, and controller (500-W, 13.56-MHz) used to supply the radiofrequency power were purchased from RF Power Products Inc. Initial test results revealed that this facility could remove the carbon-based contamination from within bulbs.

  1. Turning on LAMP

    SciTech Connect

    Bostedt, Christoph

    2014-06-30

    Christoph Bostedt, a senior staff scientist at SLAC's Linac Coherent Light Source X-ray laser, provides a sneak peek of a powerful new instrument, called LAMP, that is now available for experiments that probe the atomic and molecular realm. LAMP replaces and updates the first instrument at LCLS, dubbed CAMP, which will be installed at an X-ray laser in Germany.

  2. Turning on LAMP

    ScienceCinema

    Bostedt, Christoph

    2014-07-16

    Christoph Bostedt, a senior staff scientist at SLAC's Linac Coherent Light Source X-ray laser, provides a sneak peek of a powerful new instrument, called LAMP, that is now available for experiments that probe the atomic and molecular realm. LAMP replaces and updates the first instrument at LCLS, dubbed CAMP, which will be installed at an X-ray laser in Germany.

  3. Jacketed lamp bulb envelope

    DOEpatents

    MacLennan, Donald A.; Turner, Brian P.; Gitsevich, Aleksandr; Bass, Gary K.; Dolan, James T.; Kipling, Kent; Kirkpatrick, Douglas A.; Leng, Yongzhang; Levin, Izrail; Roy, Robert J.; Shanks, Bruce; Smith, Malcolm; Trimble, William C.; Tsai, Peter

    2001-01-01

    A jacketed lamp bulb envelope includes a ceramic cup having an open end and a partially closed end, the partially closed end defining an aperture, a lamp bulb positioned inside the ceramic cup abutting the aperture, and a reflective ceramic material at least partially covering a portion of the bulb not abutting the aperture. The reflective ceramic material may substantially fill an interior volume of the ceramic cup not occupied by the bulb. The ceramic cup may include a structural feature for aiding in alignment of the jacketed lamp bulb envelope in a lamp. The ceramic cup may include an external flange about a periphery thereof. One example of a jacketed lamp bulb envelope includes a ceramic cup having an open end and a closed end, a ceramic washer covering the open end of the ceramic cup, the washer defining an aperture therethrough, a lamp bulb positioned inside the ceramic cup abutting the aperture, and a reflective ceramic material filling an interior volume of the ceramic cup not occupied by the bulb. A method of packing a jacketed lamp bulb envelope of the type comprising a ceramic cup with a lamp bulb disposed therein includes the steps of filling the ceramic cup with a flowable slurry of reflective material, and applying centrifugal force to the cup to pack the reflective material therein.

  4. Afterbay, looking north at hydraulic gate check cylinders and lamps. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Afterbay, looking north at hydraulic gate check cylinders and lamps. The gate lift in the foreground is an addition associated with the ca. 1974-1975 regulatory pumps - Wellton-Mohawk Irrigation System, Pumping Plant No. 2, Bounded by Interstate 8 to south, Wellton, Yuma County, AZ

  5. Compact ultrafast orthogonal acceleration time-of-flight mass spectrometer for on-line gas analysis by electron impact ionization and soft single photon ionization using an electron beam pumped rare gas excimer lamp as VUV-light source.

    PubMed

    Mühlberger, F; Saraji-Bozorgzad, M; Gonin, M; Fuhrer, K; Zimmermann, R

    2007-11-01

    Orthogonal acceleration time-of-flight mass spectrometers (oaTOFMS), which are exhibiting a pulsed orthogonal extraction of ion bunches into the TOF mass analyzer from a continuous primary ion beam, are well-suited for continuous ionization methods such as electron impact ionization (EI). Recently an electron beam pumped rare gas excimer lamp (EBEL) was introduced, which emits intensive vacuum UV (VUV) radiation at, e.g., 126 nm (argon excimer) and is well suited as the light source for soft single photon ionization (SPI) of organic molecules. In this paper, a new compact oaTOFMS system which allows switching between SPI, using VUV-light from an EBEL-light source, and conventional EI is described. With the oaTOFMS system, EBEL-SPI and EI mass spectral transients can be recorded at very high repetition rates (up to 100 kHz), enabling high duty cycles and therefore good detection efficiencies. By using a transient recorder card with the capability to perform on-board accumulation of the oaTOF transients, final mass spectra with a dynamic range of 106 can be saved to the hard disk at a rate of 10 Hz. As it is possible to change the ionization modes (EI and SPI) rapidly, a comprehensive monitoring of complex gases with highly dynamic compositions, such as cigarette smoke, is possible. In this context, the EI based mass spectra address the bulk composition (compounds such as water, oxygen, carbon dioxide, etc. in the up to percentage concentration range) as well as some inorganic trace gases such as argon, sulfur dioxide, etc. down to the low ppm level. The EBEL-SPI mass spectra on the other hand are revealing the organic composition down to the lower ppb concentration range. PMID:17900147

  6. Excimer lamp stereolithography

    NASA Astrophysics Data System (ADS)

    Satoh, Saburoh; Tanaka, Takao; Ihara, Satoshi; Yamabe, Chobei

    2000-06-01

    For the laser stereo-lithography, a XeCl excimer lamp with cylindrical tube has been adopted to achieve a lower cost type UV light source. Because of excellent high output efficiency, it is possible to be down sizing of a power supplier and a lamp head and to be air-cooling. And moreover to extract the maximum output power and efficiency, we applied an optical fiber system for its lithography optics. With this excimer lamp the maximum UV emission per pulse 25 (mu) J at 100 Hz and the maximum average power 10 mW at 1000 Hz were obtained.

  7. Hollow-Core Fiber Lamp

    NASA Technical Reports Server (NTRS)

    Yi, Lin (Inventor); Tjoelker, Robert L. (Inventor); Burt, Eric A. (Inventor); Huang, Shouhua (Inventor)

    2016-01-01

    Hollow-core capillary discharge lamps on the millimeter or sub-millimeter scale are provided. The hollow-core capillary discharge lamps achieve an increased light intensity ratio between 194 millimeters (useful) and 254 millimeters (useless) light than conventional lamps. The capillary discharge lamps may include a cone to increase light output. Hollow-core photonic crystal fiber (HCPCF) may also be used.

  8. Physics of Incandescent Lamp Burnout

    ERIC Educational Resources Information Center

    Gluck, Paul; King, John

    2008-01-01

    Incandescent lamps with tungsten filaments have been in use for about a century while being gradually replaced by fluorescent lamps; in another generation both will quite probably be largely replaced by light-emitting diodes. Incandescent lamps (simply called "lamps" in what follows) burn out after a lifetime that depends mostly on the temperature…

  9. Slit-lamp exam

    MedlinePlus

    ... to light for a few hours after the exam if dilating drops are used. ... The slit lamp exam may detect many diseases of the eye, including: Clouding of the lens of the eye ( cataract ) Injury to the ...

  10. Wood's lamp examination

    MedlinePlus

    A Wood's lamp examination is a test that uses ultraviolet (UV) light to look at the skin closely. ... Gebhard RE. Wood's light examination. In: Pfenninger JL, Fowler GC, eds. ... Care . 3rd ed. Philadelphia, PA: Elsevier Mosby; 2010:chap ...

  11. Magnetic fluorescent lamp

    DOEpatents

    Berman, S.M.; Richardson R.W.

    1983-12-29

    The radiant emission of a mercury-argon discharge in a fluorescent lamp assembly is enhanced by providing means for establishing a magnetic field with lines of force along the path of electron flow through the bulb of the lamp assembly, to provide Zeeman splitting of the ultraviolet spectral line. Optimum results are obtained when the magnetic field strength causes a Zeeman splitting of approximately 1.7 times the thermal line width.

  12. 49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... specifications in FMVSS No. 108 (49 CFR 571.108), SAE J581, and SAE J583, respectively. ... lamps and front fog lamps. 393.24 Section 393.24 Transportation Other Regulations Relating to... Devices, and Electrical Wiring § 393.24 Requirements for head lamps, auxiliary driving lamps and front...

  13. Integrity Monitoring of Mercury Discharge Lamps

    NASA Technical Reports Server (NTRS)

    Tjoelker, Robert L.

    2010-01-01

    Mercury discharge lamps are critical in many trapped ion frequency standard applications. An integrity monitoring system can be implemented using end-of-life signatures observed in operational mercury discharge lamps, making it possible to forecast imminent failure and to take action to mitigate the consequences (such as switching to a redundant system). Mercury lamps are used as a source of 194-nm ultraviolet radiation for optical pumping and state selection of mercury trapped ion frequency standards. Lamps are typically fabricated using 202Hg distilled into high-purity quartz, or other 194-nm transmitting material (e.g., sapphire). A buffer gas is also placed into the bulb, typically a noble gas such as argon, neon, or krypton. The bulbs are driven by strong RF fields oscillating at .200 MHz. The lamp output may age over time by two internal mechanisms: (1) the darkening of the bulb that attenuates light transmission and (2) the loss of mercury due to migration or chemical interactions with the bulb surface. During fabrication, excess mercury is placed into a bulb, so that the loss rate is compensated with new mercury emanating from a cool tip or adjacent reservoir. The light output is nearly constant or varies slightly at a constant rate for many months/years until the mercury source is depleted. At this point, the vapor pressure abruptly falls and the total light output and atomic clock SNR (signal-to-noise ratio) decrease. After several days to weeks, the light levels decrease to a point where the atomic clock SNR is no longer sufficient to stay in lock, or the lamp self-extinguishes. This signature has been observed in four separate end-of-life lamp failures while operating in the Deep Space Network (DSN). A simple integrator circuit can observe and document steady-state lamp behavior. When the light levels drop over a predetermined time interval by a specified amount (e.g., 20 percent), an alarm is set. For critical operational applications, such as the DSN

  14. Fluorescent discharge lamp

    NASA Technical Reports Server (NTRS)

    Mukai, E.; Otsuka, H.; Nomi, K.; Honmo, I.

    1982-01-01

    A rapidly illuminating fluorescent lamp 1,200 mm long and 32.5 mm in diameter with an interior conducting strip which is compatible with conventional fixtures and ballasts is described. The fluorescent lamp is composed of a linear glass tube, electrodes sealed at both ends, mercury and raregas sealed in the glass tube, a fluorescent substance clad on the inner walls of the glass tube, and a clad conducting strip extending the entire length of the glass tube in the axial direction on the inner surface of the tube.

  15. Improved ultraviolet resonance lamp

    NASA Technical Reports Server (NTRS)

    Bass, A. M.

    1970-01-01

    Removal of the seal area from the path of the lamp discharge eliminates the gradual deterioration of lithium fluoride window surfaces from condensation of products formed by interaction of a resonant rare-gas discharge with window sealing materials. The discharge is confined to the inner tube.

  16. The fundus slit lamp.

    PubMed

    Gellrich, Marcus-Matthias

    2015-01-01

    Fundus biomicroscopy with the slit lamp as it is practiced widely nowadays was not established until the 1980-es with the introduction of the Volk lenses +90 and +60D. Thereafter little progress has been made in retinal imaging with the slit lamp. It is the aim of this paper to fully exploit the potential of a video slit lamp for fundus documentation by using easily accessible additions. Suitable still images are easily retrieved from videorecordings of slit lamp examinations. The effects of changements in the slit lamp itself (slit beam and apertures) and its examination equipment (converging lenses from +40 to +90D) on quality and spectrum of fundus images are demonstrated. Imaging software is applied for reconstruction of larger fundus areas in a mosaic pattern (Hugin®) and to perform the flicker test in order to visualize changes in the same fundus area at different points of time (Power Point®). The three lenses +90/+60/+40D are a good choice for imaging the whole spectrum of retinal diseases. Displacement of the oblique slit light can be used to assess changes in the surface profile of the inner retina which occurs e.g. in macular holes or pigment epithelial detachment. The mosaic function in its easiest form (one strip macula adapted to one strip with the optic disc) provides an overview of the posterior pole comparable to a fundus camera's image. A reconstruction of larger fundus areas is feasible for imaging in vitreoretinal surgery or occlusive vessel disease. The flicker test is a fine tool for monitoring progressive glaucoma by changes in the optic disc, and it is also a valuable diagnostic tool in macular disease. Nearly all retinal diseases can be imaged with the slit lamp - irrespective whether they affect the posterior pole, mainly the optic nerve or the macula, the whole retina or only its periphery. Even a basic fundus controlled perimetry is possible. Therefore fundus videography with the slit lamp is a worthwhile approach especially for the

  17. Lunar Impact Flash Locations

    NASA Technical Reports Server (NTRS)

    Moser, D. E.; Suggs, R. M.; Kupferschmidt, L.; Feldman, J.

    2015-01-01

    A bright impact flash detected by the NASA Lunar Impact Monitoring Program in March 2013 brought into focus the importance of determining the impact flash location. A process for locating the impact flash, and presumably its associated crater, was developed using commercially available software tools. The process was successfully applied to the March 2013 impact flash and put into production on an additional 300 impact flashes. The goal today: provide a description of the geolocation technique developed.

  18. Dimming of metal halide lamps

    NASA Technical Reports Server (NTRS)

    Schurer, Kees

    1994-01-01

    We ran some tests on the effect of dimming of metal halide (MH) lamps upon the stability and the spectral quality of the light output. Lamps used were a new Philips lamp HPI-T 250W, a similar Philips lamp with a few thousand burning hours and a new Osram lamp HQI-T 250W/D. The ballast was a BBC type DJ 250/2KS, the starter a BAS TORGI type MZN 250 SE and the dimmer an Elstrom Control System type ERHQ-T 250. Power was derived from a Philips stabilizer, type PE 1602. Lamp output was monitored with a PAR meter. Spectra were taken at 100% and at 50% output as measured with the PAR meter. Lamps were allowed to stabilize at any setting for 30 minutes before measurements were made. Lamp manufacturers advise against dimming for fear of poor stability and intolerable changes of the spectrum. However, none of the lamps showed a decrease in stability, no flicker or wandering of the discharge, and the changes of the spectrum were not negligible, but certainly not dramatic. Lamps of either manufacture retain their white color, relative peak heights of spectral lines did shift, but no gaps in the spectrum occurred. Spectra taken at 50% with 30 minutes intervals coincided. Differences between the new and the older Philips lamp were noticeable, but not really significant.

  19. The orthoptic slit lamp.

    PubMed

    Gellrich, Marcus-Matthias

    2013-12-01

    Recently we presented our concept of "videography with the slit lamp," which provides an imaging solution for nearly every pathological finding in ophthalmology. This paper deals with the changes that must be made to prepare the slit lamp for documenting squint. To achieve this goal we propose: 1. Changes in the observation system: minus lenses in front of the objective of the slit lamp to achieve a sharp image of both eyes (eg, -8 diopters [dpt] if the patient sits at a distance of 50 cm). 2. Changes in the illumination system: minimizing the narrowed angle between illumination and observation axis by holding a "recentration" prism of 14 dpt horizontally in front of the slit light. This procedure creates equally sufficient illumination of the patient's face and central corneal reflexes. 3. Recording clinical findings with a digital recorder. This enables us to identify binocular eye positions, which sometimes last only part of a second, eg, in latent or intermittent strabism. 4. Visualizing clinical findings by using Microsoft PowerPoint® to build up 9-gaze composites or adjust corneal reflexes on subsequent foils. Changes in binocular eye positions (eg, after surgery, but also during diagnostic covering) can be made visible by flickering between the foils to compare. PMID:24090104

  20. Investigations on the potential of a novel diode pumped Er:YAG laser system for dental applications

    NASA Astrophysics Data System (ADS)

    Stock, Karl; Hausladen, Florian; Hibst, Raimund

    2012-01-01

    The successful clinical application of the Er:YAG-laser in dentistry is well known, documented by numerous published studies. These lasers are flash lamp pumped systems and emit pulses of typically some 100 μs duration with energies of up to 1 J. Pulse repetition rates can reach up to 100Hz, and mean powers are up to about 8W. As an alternative to these laser systems recently a novel diode pumped Er:YAG laser system (Pantec Engineering AG) became available. This laser can provide a pulse repetition rate up to 2kHz and a mean laser power up to 15W. The aim of the presented study is to investigate the effect of this laser system on dental hard and soft tissue at various irradiation parameters, particular at repetition rates more than 100 Hz. At first an appropriate experimental set-up was realized with a beam delivery and focusing unit, a computer controlled stepper unit with sample holder, and a shutter unit. The stepper unit allows to move the samples (dentin or enamel slides of extracted human teeth, chicken breast, pig bone) with a defined velocity during irradiation by various laser parameters. For rinsing the sample surface a water spray was also included. The laser produced grooves and cuts were analyzed by light microscopy and laser scanning microscopy regarding to the ablation quality, geometry, ablation efficacy, and thermal effects. The grooves in dentin and enamel show a rough surface, typical for Er:YAG laser ablation. The craters are slightly cone shaped with sharp edges on the surface. Water cooling is essential to prevent thermal injury. The ablation efficacy in dentin is comparable to literature values of the flash lamp pumped Er:YAG laser. The cutting of bone and soft tissue is excellent and appears superior to earlier results obtained with flash lamp pumped system. As a further advantage, the broad range of repetition rates allows to widely vary the thermal side effects. In conclusion, these first experiments with a diode pumped Er:YAG laser

  1. Wedge Heat-Flux Indicators for Flash Thermography

    NASA Technical Reports Server (NTRS)

    Koshti, Ajay M.

    2003-01-01

    Wedge indicators have been proposed for measuring thermal radiation that impinges on specimens illuminated by flash lamps for thermographic inspection. Heat fluxes measured by use of these indicators would be used, along with known thermal, radiative, and geometric properties of the specimens, to estimate peak flash temperatures on the specimen surfaces. These indicators would be inexpensive alternatives to high-speed infrared pyrometers, which would otherwise be needed for measuring peak flash surface temperatures. The wedge is made from any suitable homogenous material such as plastic. The choice of material is governed by the equation given. One side of the wedge is covered by a temperature sensitive compound that decomposes irreversibly when its temperature exceeds a rated temperature (T-rated). The uncoated side would be positioned alongside or in place of the specimen and exposed to the flash, then the wedge thickness at the boundary between the white and blackened portions measured.

  2. Physics of Incandescent Lamp Burnout

    NASA Astrophysics Data System (ADS)

    Gluck, Paul; King, John

    2008-01-01

    Incandescent lamps with tungsten filaments have been in use for about a century while being gradually replaced by fluorescent lamps; in another generation both will quite probably be largely replaced by light-emitting diodes. Incandescent lamps (simply called lamps in what follows) burn out after a lifetime that depends mostly on the temperature of the filament and hence the applied voltage. A full-term project (about 100 hours) on lamp burnout was carried out by two students in 1965 and has been briefly described. Many aspects of the physics of lamps have been dealt with in articles that have appeared in this journal, in the American Journal of Physics, and in Physics Education.2,3

  3. High brightness microwave lamp

    DOEpatents

    Kirkpatrick, Douglas A.; Dolan, James T.; MacLennan, Donald A.; Turner, Brian P.; Simpson, James E.

    2003-09-09

    An electrodeless microwave discharge lamp includes a source of microwave energy, a microwave cavity, a structure configured to transmit the microwave energy from the source to the microwave cavity, a bulb disposed within the microwave cavity, the bulb including a discharge forming fill which emits light when excited by the microwave energy, and a reflector disposed within the microwave cavity, wherein the reflector defines a reflective cavity which encompasses the bulb within its volume and has an inside surface area which is sufficiently less than an inside surface area of the microwave cavity. A portion of the reflector may define a light emitting aperture which extends from a position closely spaced to the bulb to a light transmissive end of the microwave cavity. Preferably, at least a portion of the reflector is spaced from a wall of the microwave cavity. The lamp may be substantially sealed from environmental contamination. The cavity may include a dielectric material is a sufficient amount to require a reduction in the size of the cavity to support the desired resonant mode.

  4. Inductive tuners for microwave driven discharge lamps

    SciTech Connect

    Simpson, J.E.

    1999-11-02

    An RF powered electrodeless lamp utilizing an inductive tuner in the waveguide which couples the RF power to the lamp cavity, for reducing reflected RF power and causing the lamp to operate efficiently.

  5. Inductive tuners for microwave driven discharge lamps

    DOEpatents

    Simpson, James E.

    1999-01-01

    An RF powered electrodeless lamp utilizing an inductive tuner in the waveguide which couples the RF power to the lamp cavity, for reducing reflected RF power and causing the lamp to operate efficiently.

  6. High power diode lasers for solid-state laser pumps

    NASA Technical Reports Server (NTRS)

    Linden, Kurt J.; Mcdonnell, Patrick N.

    1994-01-01

    The development and commercial application of high power diode laser arrays for use as solid-state laser pumps is described. Such solid-state laser pumps are significantly more efficient and reliable than conventional flash-lamps. This paper describes the design and fabrication of diode lasers emitting in the 780 - 900 nm spectral region, and discusses their performance and reliability. Typical measured performance parameters include electrical-to-optical power conversion efficiencies of 50 percent, narrow-band spectral emission of 2 to 3 nm FWHM, pulsed output power levels of 50 watts/bar with reliability values of over 2 billion shots to date (tests to be terminated after 10 billion shots), and reliable operation to pulse lengths of 1 ms. Pulse lengths up to 5 ms have been demonstrated at derated power levels, and CW performance at various power levels has been evaluated in a 'bar-in-groove' laser package. These high-power 1-cm stacked-bar arrays are now being manufactured for OEM use. Individual diode laser bars, ready for package-mounting by OEM customers, are being sold as commodity items. Commercial and medical applications of these laser arrays include solid-state laser pumping for metal-working, cutting, industrial measurement and control, ranging, wind-shear/atmospheric turbulence detection, X-ray generation, materials surface cleaning, microsurgery, ophthalmology, dermatology, and dental procedures.

  7. High power diode lasers for solid-state laser pumps

    NASA Astrophysics Data System (ADS)

    Linden, Kurt J.; McDonnell, Patrick N.

    1994-02-01

    The development and commercial application of high power diode laser arrays for use as solid-state laser pumps is described. Such solid-state laser pumps are significantly more efficient and reliable than conventional flash-lamps. This paper describes the design and fabrication of diode lasers emitting in the 780 - 900 nm spectral region, and discusses their performance and reliability. Typical measured performance parameters include electrical-to-optical power conversion efficiencies of 50 percent, narrow-band spectral emission of 2 to 3 nm FWHM, pulsed output power levels of 50 watts/bar with reliability values of over 2 billion shots to date (tests to be terminated after 10 billion shots), and reliable operation to pulse lengths of 1 ms. Pulse lengths up to 5 ms have been demonstrated at derated power levels, and CW performance at various power levels has been evaluated in a 'bar-in-groove' laser package. These high-power 1-cm stacked-bar arrays are now being manufactured for OEM use. Individual diode laser bars, ready for package-mounting by OEM customers, are being sold as commodity items. Commercial and medical applications of these laser arrays include solid-state laser pumping for metal-working, cutting, industrial measurement and control, ranging, wind-shear/atmospheric turbulence detection, X-ray generation, materials surface cleaning, microsurgery, ophthalmology, dermatology, and dental procedures.

  8. TIR lenses for fluorescent lamps

    NASA Astrophysics Data System (ADS)

    Parkyn, William A.; Pelka, David G.

    1995-08-01

    The total internal reflection lens has been successfully applied to the efficient collimation of light from incandescent lamps and light-emitting diodes, and it is currently being marketed in several retail products. These circularly symmetric designs operated with relatively small sources. Two new forms of the TIR lens have been designed, and prototypes fabricated, for forming beams from fluorescent lamps. The toroidal fluorescent lamp is formed by circularly sweeping a faceted profile about its outer edge. A 5 inch diameter prototype lens has been diamond turned, and has 80% efficiency. When covering a 2.5 inch toroidal source of 0.25 inch minor diameter, it forms a smooth structureless beam of 40 degrees FWHM. The linear TIR lens has a faceted profile that is extended in cylindrical symmetry. In conjunction with a planar back mirror, a 6 inch diameter lens collects 85% of the light from a 5/8 inch lamp. The full width at half maximum is 30 degrees transversely and 120 degrees longitudinally, in a stripe pattern with twin peaks at +/- 47 degrees parallel to the lamp axis. These designs are applicable to other tubular light sources: discharge lamps, such as aircraft strobes and camera flashlamps, as well as neon lamps. They offer greater efficiency, narrower beamwidths, and much more compact profiles than conventional relfector designs.

  9. Evaluation of GOES encoder lamps

    NASA Technical Reports Server (NTRS)

    Viehmann, W.; Helmold, N.

    1983-01-01

    Aging characteristics and life expectancies of flight quality, tungsten filament, encoder lamps are similar to those of 'commercial' grade gas filled lamps of similar construction, filament material and filament temperature. The aging and final failure by filament burnout are caused by single crystal growth over large portions of the filament with the concomitant development of facets and notches resulting in reduction of cross section and mechanical weakening of the filament. The life expectancy of presently produced lamps is about one year at their nominal operating voltage of five volts dc. At 4.5 volts, it is about two years. These life times are considerably shorter, and the degradation rates of lamp current and light flux are considerably higher, than were observed in the laboratory and in orbit on lamps of the same type manufactured more than a decade ago. It is speculated that the filaments of these earlier lamps contained a crystallization retarding dopant, possibly thorium oxide. To obtain the desired life expectancy of or = to four years in present lamps, operating voltages of or = to four volts dc would be required.

  10. Flash Diffusivity Technique Applied to Individual Fibers

    NASA Technical Reports Server (NTRS)

    Mayeaux, Brian; Yowell, Leonard; Wang, Hsin

    2007-01-01

    A variant of the flash diffusivity technique has been devised for determining the thermal diffusivities, and thus the thermal conductivities, of individual aligned fibers. The technique is intended especially for application to nanocomposite fibers, made from narrower fibers of polyphenylene benzobisthiazole (PBZT) and carbon nanotubes. These highly aligned nanocomposite fibers could exploit the high thermal conductivities of carbon nanotubes for thermal-management applications. In the flash diffusivity technique as practiced heretofore, one or more heat pulse(s) is (are) applied to the front face of a plate or disk material specimen and the resulting time-varying temperature on the rear face is measured. Usually, the heat pulse is generated by use of a xenon flash lamp, and the variation of temperature on the rear face is measured by use of an infrared detector. The flash energy is made large enough to produce a usefully high temperature rise on the rear face, but not so large as to significantly alter the specimen material. Once the measurement has been completed, the thermal diffusivity of the specimen is computed from the thickness of the specimen and the time dependence of the temperature variation on the rear face. Heretofore, the infrared detector used in the flash diffusivity technique has been a single-point detector, which responds to a spatial average of the thermal radiation from the rear specimen surface. Such a detector cannot distinguish among regions of differing diffusivity within the specimen. Moreover, two basic assumptions of the thermaldiffusivity technique as practiced heretofore are that the specimen is homogeneous and that heat flows one-dimensionally from the front to the rear face. These assumptions are not valid for an inhomogeneous (composite) material.

  11. Flash protection controller

    DOEpatents

    Galbraith, Lee K.

    1981-01-01

    A controller provides a high voltage to maintain an electro-optic shutter in a transparent condition until a flash of light which would be harmful to personnel is sensed by a phototransistor. The controller then shorts the shutter to ground to minimize light transmission to the user and maintains light transmission at the pre-flash level for a predetermined time to allow the flash to subside. A log converter and differential trigger circuit keep the controller from being triggered by other light flashes which are not dangerous.

  12. Apollo light flash investigations

    NASA Technical Reports Server (NTRS)

    Osborne, W. Z.; Pinsky, L. S.; Bailey, J. V.

    1975-01-01

    The visual phenomenon of light flashes resulting from high energy, heavy cosmic rays penetrating the command module structure and crewmembers' eyes is investigated. Light flash events observed during dedicated sessions on Apollo 15, 16, 17 are described along with a Monte Carlo simulation of the exposure of an astronaut to cosmic radiation during a mission. Results of the Apollo Light Flash Moving Emulsion Detector experiment developed for Apollo 16 and 17 to obtain a direct record of incident cosmic ray particles are correlated with crewmembers' reports of light flashes.

  13. Flash protection controller

    DOEpatents

    Galbraith, L.K.

    1979-12-07

    A controller provides a high voltage to maintain an electro-optic shutter in a transparent condition until a flash of light which would be harmful to personnel is sensed by a phototransistor. The controller then shorts the shutter to ground to minimize light transmission to the user and maintains light transmission at the pre-flash level for a predetermined time to allow the flash to subside. A log converter and differential trigger circuit keep the controller from being triggered by other light flashes which are not dangerous.

  14. Custom blending of lamp phosphors

    NASA Technical Reports Server (NTRS)

    Klemm, R. E.

    1978-01-01

    Spectral output of fluorescent lamps can be precisely adjusted by using computer-assisted analysis for custom blending lamp phosphors. With technique, spectrum of main bank of lamps is measured and stored in computer memory along with emission characteristics of commonly available phosphors. Computer then calculates ratio of green and blue intensities for each phosphor according to manufacturer's specifications and plots them as coordinates on graph. Same ratios are calculated for measured spectrum. Once proper mix is determined, it is applied as coating to fluorescent tubing.

  15. Possibilities of increasing the pumping efficiency of solid active medium laser generators by optimizing the pumping cavity profile

    NASA Astrophysics Data System (ADS)

    Dontu, O.; Ganatsios, S.; Alexandrescu, N.

    2008-03-01

    The paper presents some design elements concerning the optical pumping cavities of the laser generators with active solid medium, as well as the way of increasing their performance. We start from the fact that the laser cavity is a closed optical system, where the active laser medium and the pumping source are conjugated, in order to achieve a maximum concentration of the light flux of the pumping source towards the active medium. We discuss the simple elliptical section laser pumping cavities (with one pumping lamp) and triple elliptical (with three lamps), also presenting a series on calculus nomograms, very useful to those who design the laser generation optical pumping cavities.

  16. LAMP Observes the LCROSS Plume

    NASA Video Gallery

    This video shows LAMP’s view of the LCROSS plume. The first half of the animation shows the LAMP viewport scanning across the horizon, passing through the plume, and moving on. The second half of...

  17. Lamp for generating high power ultraviolet radiation

    DOEpatents

    Morgan, Gary L.; Potter, James M.

    2001-01-01

    The apparatus is a gas filled ultraviolet generating lamp for use as a liquid purifier. The lamp is powred by high voltage AC, but has no metallic electrodes within or in contact with the gas enclosure which is constructed as two concentric quartz cylinders sealed together at their ends with the gas fill between the cylinders. Cooling liquid is pumped through the volume inside the inner quartz cylinder where an electrically conductive pipe spaced from the inner cylinder is used to supply the cooling liquid and act as the high voltage electrode. The gas enclosure is enclosed within but spaced from a metal housing which is connected to operate as the ground electrode of the circuit and through which the treated fluid flows. Thus, the electrical circuit is from the central pipe, and through the cooling liquid, the gas enclosure, the treated liquid on the outside of the outer quartz cylinder, and to the housing. The high voltage electrode is electrically isolated from the source of cooling liquid by a length of insulated hose which also supplies the cooling liquid.

  18. 49 CFR 393.25 - Requirements for lamps other than head lamps.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Requirements for lamps other than head lamps. 393.25 Section 393.25 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL... Wiring § 393.25 Requirements for lamps other than head lamps. (a) Mounting. All lamps shall be...

  19. 49 CFR 393.25 - Requirements for lamps other than head lamps.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Requirements for lamps other than head lamps. 393.25 Section 393.25 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL... Wiring § 393.25 Requirements for lamps other than head lamps. (a) Mounting. All lamps shall be...

  20. Note: Hollow cathode lamp with integral, high optical efficiency isolation valve: a modular vacuum ultraviolet source.

    PubMed

    Roberts, F Sloan; Anderson, Scott L

    2013-12-01

    The design and operating conditions of a hollow cathode discharge lamp for the generation of vacuum ultraviolet radiation, suitable for ultrahigh vacuum (UHV) application, are described in detail. The design is easily constructed, and modular, allowing it to be adapted to different experimental requirements. A thin isolation valve is built into one of the differential pumping stages, isolating the discharge section from the UHV section, both for vacuum safety and to allow lamp maintenance without venting the UHV chamber. The lamp has been used both for ultraviolet photoelectron spectroscopy of surfaces and as a "soft" photoionization source for gas-phase mass spectrometry. PMID:24387477

  1. Note: Hollow cathode lamp with integral, high optical efficiency isolation valve: A modular vacuum ultraviolet source

    SciTech Connect

    Sloan Roberts, F.; Anderson, Scott L.

    2013-12-15

    The design and operating conditions of a hollow cathode discharge lamp for the generation of vacuum ultraviolet radiation, suitable for ultrahigh vacuum (UHV) application, are described in detail. The design is easily constructed, and modular, allowing it to be adapted to different experimental requirements. A thin isolation valve is built into one of the differential pumping stages, isolating the discharge section from the UHV section, both for vacuum safety and to allow lamp maintenance without venting the UHV chamber. The lamp has been used both for ultraviolet photoelectron spectroscopy of surfaces and as a “soft” photoionization source for gas-phase mass spectrometry.

  2. Comparison of TID Response and SEE Characterization of Single and Multi Level High Density NAND Flash Memories

    NASA Technical Reports Server (NTRS)

    Irom, Farokh; Nguyen, Duc N.; Harboe-Sorensen, Reno; Virtanen, Ari

    2009-01-01

    Heavy ion single-event measurements and TID response for 8Gb commercial NAND flash memories are reported. Radiation results of multi-level flash technology are compared with results from single-level flash technology. In general, these commercial high density memories appear to be much less susceptible to SEE and have better TID response compared to older generations of flash memories. The charge pump survived up to 600 krads.

  3. Flash-Type Discrimination

    NASA Technical Reports Server (NTRS)

    Koshak, William J.

    2010-01-01

    This viewgraph presentation describes the significant progress made in the flash-type discrimination algorithm development. The contents include: 1) Highlights of Progress for GLM-R3 Flash-Type discrimination Algorithm Development; 2) Maximum Group Area (MGA) Data; 3) Retrieval Errors from Simulations; and 4) Preliminary Global-scale Retrieval.

  4. NUCLEAR FLASH TYPE STEAM GENERATOR

    DOEpatents

    Johns, F.L.; Gronemeyer, E.C.; Dusbabek, M.R.

    1962-09-01

    A nuclear steam generating apparatus is designed so that steam may be generated from water heated directly by the nuclear heat source. The apparatus comprises a pair of pressure vessels mounted one within the other, the inner vessel containing a nuclear reactor heat source in the lower portion thereof to which water is pumped. A series of small ports are disposed in the upper portion of the inner vessel for jetting heated water under pressure outwardly into the atmosphere within the interior of the outer vessel, at which time part of the jetted water flashes into steam. The invention eliminates the necessity of any intermediate heat transfer medium and components ordinarily required for handling that medium. (AEC)

  5. Understanding Green Flashes

    NASA Astrophysics Data System (ADS)

    Young, Andrew T.

    1998-05-01

    Most astronomers learn about green flashes from either Minnaert's old book (Dover, 1954) or O'Connell's ``The Green Flash....'' Both have defects. Minnaert's account mostly represents what was known in the 1920s; it repeats Mulder's 3-fold classification, which omits Joule's second type of flash --- the one most commonly seen from mountain observatories. O'Connell searched only the astronomical literature, missing Dietze's crucially important paper (Z.f.Met. 9, 169 (1955)) showing that the ``textbook'' mechanism cannot produce flashes visible to the naked eye. He also erred in thinking that distortions of the setting Sun arise in the upper atmosphere (they are due to the marine boundary layer), and copied an error from Feenstra Kuiper's thesis that misidentified a common mirage-like phenomenon as Wegener's ``blank strip'' (Young et al., Appl. Opt. 36, 2689 (1997).) Most phenomena shown in O'Connell's book are caused by inversion layers below eye level, not above as in Wegener's phenomenon. The two commonest forms of green flash are associated with the inferior mirage and the mock mirage, corresponding to Fisher's Type A and Type B sunsets, respectively. Superrefraction, advocated by Wood and by Rayleigh as the cause of large flashes, actually suppress them: the airmass is proportional to the refraction (by Laplace's extinction theorem), so no green is transmitted when refraction is much larger than average. Although there is a physical green flash that can be photographed, the colors seen at sunset are strongly modified by bleaching of the L cones. Most ``green'' sunset flashes are actually yellow. Writers should stop representing Jules Verne's ``ancient legend'' as fact, as it was invented by Verne as a plot device for his novel ``Le Rayon Vert.'' Green-flash photos and simulations will be shown. This material is based upon work supported by the NSF under Award No. ATM-9714357.

  6. High pressure neon arc lamp

    DOEpatents

    Sze, Robert C.; Bigio, Irving J.

    2003-07-15

    A high pressure neon arc lamp and method of using the same for photodynamic therapies is provided. The high pressure neon arc lamp includes a housing that encloses a quantity of neon gas pressurized to about 500 Torr to about 22,000 Torr. At each end of the housing the lamp is connected by electrodes and wires to a pulse generator. The pulse generator generates an initial pulse voltage to breakdown the impedance of the neon gas. Then the pulse generator delivers a current through the neon gas to create an electrical arc that emits light having wavelengths from about 620 nanometers to about 645 nanometers. A method for activating a photosensitizer is provided. Initially, a photosensitizer is administered to a patient and allowed time to be absorbed into target cells. Then the high pressure neon arc lamp is used to illuminate the target cells with red light having wavelengths from about 620 nanometers to about 645 nanometers. The red light activates the photosensitizers to start a chain reaction that may involve oxygen free radicals to destroy the target cells. In this manner, a high pressure neon arc lamp that is inexpensive and efficiently generates red light useful in photodynamic therapy is provided.

  7. Floods and Flash Flooding

    MedlinePlus

    Floods and flash flooding Now is the time to determine your area’s flood risk. If you are not sure whether you ... If you are in a floodplain, consider buying flood insurance. Do not drive around barricades. If your ...

  8. Flash Bulletin: Fireflies

    ERIC Educational Resources Information Center

    Brown, Debbie

    1984-01-01

    Explains the flashes of light emitted by fireflies as competition, species-specific code, species identification and mating behavior and ecology. Suggests activities to conduct to study the insects and their behavior. (ERB)

  9. Flashes and Floaters

    MedlinePlus

    ... either in the form of lightening bolts, shooting stars, sparks, or an arc of light to the ... against it that causes the sparks and shooting stars phenomenon. But flashes and floaters may have more ...

  10. A polychromatic flash photolysis apparatus (PFPA).

    PubMed

    Uhl, R; Meyer, B; Desel, H

    1984-11-01

    A wide variety of biologically relevant chemical intermediates have been identified and characterised by their spectral properties. When rapid kinetics, i.e. rapid changes in these spectral properties are studied, the equipment designed for these studies (flash photolysis-, T-jump apparatus) usually allows only the registration of intensity changes of the monitoring light beam at one particular wavelength. Quite frequently, however, particularly in biological systems, the reactions of interest are too complex to be fully understood using single wavelength techniques. We have therefore designed and built a flash photolysis apparatus which permits the simultaneous recording of absorbance changes at 32 wavelengths, freely selectable between 300 and 1000 nm, as well as changes in fluorescence, luminescence, birefringence and light scattering. The apparatus, which we have called Polychromatic Flash Photolysis Apparatus (PFPA), acquires up to 8000 difference spectra per second with an amplitude resolution of better than 0.0001 absorbance unit. Data acquisition and activation of an actinic xenon flash unit occurs under computer control. The same computer is responsible for data storage, handling and graphic display. This communication describes the PFPA, its performance, and, as a demonstration of its potential usefulness, its application to the measurement of the light driven photocycle of bacterial rhodopsin, the proton pumping protein of Halobacterium halobium. PMID:6520324

  11. LAMP: Peering Into the Lunar Dark

    NASA Video Gallery

    The Lyman-Alpha Mapping Project (LAMP) is an instrument on NASA’s Lunar Reconnaissance Orbiter mission to map and study the moon. LAMP is a spectrograph that images the ultraviolet region of the...

  12. Single photon ionization time-of-flight mass spectrometry with a pulsed electron beam pumped excimer VUV lamp for on-line gas analysis: setup and first results on cigarette smoke and human breath.

    PubMed

    Mühlberger, F; Streibel, T; Wieser, J; Ulrich, A; Zimmermann, R

    2005-11-15

    Single-photon ionization (SPI) using vacuum ultraviolet (VUV) light produced by an electron beam pumped rare gas excimer source has been coupled to a compact and mobile time-of-flight mass spectrometer (TOFMS). The novel device enables real-time on-line monitoring of organic trace substances in complex gaseous matrixes down to the ppb range. The pulsed VUV radiation of the light source is employed for SPI in the ion source of the TOFMS. Ion extraction is also carried out in a pulsed mode with a short time delay with respect to ionization. The experimental setup of the interface VUV light source/time-of-flight mass spectrometer is described, and the novel SPI-TOFMS system is characterized by means of standard calibration gases. Limits of detection down to 50 ppb for aliphatic and aromatic hydrocarbons were achieved. First on-line applications comprised real-time measurements of aromatic and aliphatic trace compounds in mainstream cigarette smoke, which represents a highly dynamic fluctuating gaseous matrix. Time resolution was sufficient to monitor the smoking process on a puff-by-puff resolved basis. Furthermore, human breath analysis has been carried out to detect differences in the breath of a smoker and a nonsmoker, respectively. Several well-known biomarkers for smoke could be identified in the smoker's breath. The possibility for even shorter measurement times while maintaining the achieved sensitivity makes this new device a promising tool for on-line analysis of organic trace compounds in process gases or biological systems. PMID:16285693

  13. Thermal analysis of a linear infrared lamp

    SciTech Connect

    Nakos, J.T.

    1982-01-01

    A theoretical and experimental analysis of an infrared lamp is presented based on radiant heat transfer theory. The analysis is performed on a specific type of linear lamp which has a coiled tungsten filament surrounded by a fused quartz envelope. The purpose of the study was to model the lamp thermally, not electrically, to arrive at a better understanding of the operation of the lamp.

  14. Vibration-Resistant Support for Halide Lamps

    NASA Technical Reports Server (NTRS)

    Kiss, J.

    1987-01-01

    Lamp envelope protected against breakage. Old and new mounts for halide arc lamp sealed in housing with parabolic refector and quartz window. New version supports lamp with compliant garters instead of rigid brazed joint at top and dimensionally unstable finger stock at bottom.

  15. 21 CFR 890.5500 - Infrared lamp.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Infrared lamp. 890.5500 Section 890.5500 Food and... PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp. (a) Identification. An infrared lamp is a device intended for medical purposes that emits energy at...

  16. 21 CFR 890.5500 - Infrared lamp.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Infrared lamp. 890.5500 Section 890.5500 Food and... PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp. (a) Identification. An infrared lamp is a device intended for medical purposes that emits energy at...

  17. 21 CFR 890.5500 - Infrared lamp.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Infrared lamp. 890.5500 Section 890.5500 Food and... PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp. (a) Identification. An infrared lamp is a device intended for medical purposes that emits energy at...

  18. 21 CFR 890.5500 - Infrared lamp.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Infrared lamp. 890.5500 Section 890.5500 Food and... PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp. (a) Identification. An infrared lamp is a device intended for medical purposes that emits energy at...

  19. 21 CFR 890.5500 - Infrared lamp.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Infrared lamp. 890.5500 Section 890.5500 Food and... PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp. (a) Identification. An infrared lamp is a device intended for medical purposes that emits energy at...

  20. 30 CFR 57.17010 - Electric lamps.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric lamps. 57.17010 Section 57.17010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....17010 Electric lamps. Individual electric lamps shall be carried for illumination by all...

  1. 30 CFR 57.17010 - Electric lamps.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric lamps. 57.17010 Section 57.17010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....17010 Electric lamps. Individual electric lamps shall be carried for illumination by all...

  2. 30 CFR 57.17010 - Electric lamps.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric lamps. 57.17010 Section 57.17010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....17010 Electric lamps. Individual electric lamps shall be carried for illumination by all...

  3. 30 CFR 57.17010 - Electric lamps.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric lamps. 57.17010 Section 57.17010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....17010 Electric lamps. Individual electric lamps shall be carried for illumination by all...

  4. 30 CFR 57.17010 - Electric lamps.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric lamps. 57.17010 Section 57.17010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....17010 Electric lamps. Individual electric lamps shall be carried for illumination by all...

  5. Flash fire propensity of materials

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Cumming, H. J.

    1977-01-01

    Flash fire test results on 86 materials, evaluated using the USF flash fire screening test, are presented. The materials which appear least prone to flash fires are PVC, polyphenylene oxide and sulfide, and polyether and polyaryl sulfone; these did not produce flash fires under these particular test conditions. The principal value of these screening tests at the present time is in identifying materials which appear prone to flash fires, and in identifying which formulations of a generic material are more or less prone to flash fires.

  6. An artificial molecular pump.

    PubMed

    Cheng, Chuyang; McGonigal, Paul R; Schneebeli, Severin T; Li, Hao; Vermeulen, Nicolaas A; Ke, Chenfeng; Stoddart, J Fraser

    2015-06-01

    Carrier proteins consume fuel in order to pump ions or molecules across cell membranes, creating concentration gradients. Their control over diffusion pathways, effected entirely through noncovalent bonding interactions, has inspired chemists to devise artificial systems that mimic their function. Here, we report a wholly artificial compound that acts on small molecules to create a gradient in their local concentration. It does so by using redox energy and precisely organized noncovalent bonding interactions to pump positively charged rings from solution and ensnare them around an oligomethylene chain, as part of a kinetically trapped entanglement. A redox-active viologen unit at the heart of a dumbbell-shaped molecular pump plays a dual role, first attracting and then repelling the rings during redox cycling, thereby enacting a flashing energy ratchet mechanism with a minimalistic design. Our artificial molecular pump performs work repetitively for two cycles of operation and drives rings away from equilibrium toward a higher local concentration. PMID:25984834

  7. Adiabatically driven Brownian pumps.

    PubMed

    Rozenbaum, Viktor M; Makhnovskii, Yurii A; Shapochkina, Irina V; Sheu, Sheh-Yi; Yang, Dah-Yen; Lin, Sheng Hsien

    2013-07-01

    We investigate a Brownian pump which, being powered by a flashing ratchet mechanism, produces net particle transport through a membrane. The extension of the Parrondo's approach developed for reversible Brownian motors [Parrondo, Phys. Rev. E 57, 7297 (1998)] to adiabatically driven pumps is given. We demonstrate that the pumping mechanism becomes especially efficient when the time variation of the potential occurs adiabatically fast or adiabatically slow, in perfect analogy with adiabatically driven Brownian motors which exhibit high efficiency [Rozenbaum et al., Phys. Rev. E 85, 041116 (2012)]. At the same time, the efficiency of the pumping mechanism is shown to be less than that of Brownian motors due to fluctuations of the number of particles in the membrane. PMID:23944411

  8. An artificial molecular pump

    NASA Astrophysics Data System (ADS)

    Cheng, Chuyang; McGonigal, Paul R.; Schneebeli, Severin T.; Li, Hao; Vermeulen, Nicolaas A.; Ke, Chenfeng; Stoddart, J. Fraser

    2015-06-01

    Carrier proteins consume fuel in order to pump ions or molecules across cell membranes, creating concentration gradients. Their control over diffusion pathways, effected entirely through noncovalent bonding interactions, has inspired chemists to devise artificial systems that mimic their function. Here, we report a wholly artificial compound that acts on small molecules to create a gradient in their local concentration. It does so by using redox energy and precisely organized noncovalent bonding interactions to pump positively charged rings from solution and ensnare them around an oligomethylene chain, as part of a kinetically trapped entanglement. A redox-active viologen unit at the heart of a dumbbell-shaped molecular pump plays a dual role, first attracting and then repelling the rings during redox cycling, thereby enacting a flashing energy ratchet mechanism with a minimalistic design. Our artificial molecular pump performs work repetitively for two cycles of operation and drives rings away from equilibrium toward a higher local concentration.

  9. 14. INTERIOR VIEW, DETAIL OF TRIMMED FLASH; FLASH IS EXCESS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. INTERIOR VIEW, DETAIL OF TRIMMED FLASH; FLASH IS EXCESS METAL EXTRUDED BETWEEN THE DIES USED TO FORGE THE BLADE END OF THE POST HOLE DIGGER - Warwood Tool Company, Foot of Nineteenth Street, Wheeling, Ohio County, WV

  10. Selective removal of dental caries with a diode-pumped Er:YAG laser

    NASA Astrophysics Data System (ADS)

    Yan, Ruth; Chan, Kenneth H.; Tom, Henry; Simon, Jacob C.; Darling, Cynthia L.; Fried, Daniel

    2015-02-01

    Selective removal of caries lesions with high precision is best accomplished using lasers operating at high pulse repetition rates utilizing small spot sizes. Conventional flash-lamp pumped Er:YAG lasers are poorly suited for this purpose, but new diode-pumped Er:YAG lasers have become available operating at high pulse repetition rates. The purpose of this study was to measure the ablation rate and selectivity of sound and demineralized enamel and dentin for a 30 W diode-pumped Er:YAG laser operating with a pulse duration of 20-30-μs and evaluate it's potential for the selective removal of natural occlusal lesions on extracted teeth. Microradiography was used to determine the mineral content of the demineralized enamel and dentin of 300-μm thick sections with natural caries lesions prior to laser ablation. The ablation rate was calculated for varying mineral content. In addition, near-IR reflectance measurements at 1500-1700- nm were used to guide the laser for the selective ablation of natural occlusal caries lesions on extracted teeth.

  11. Selective removal of dental composite with a diode-pumped Er:YAG laser

    NASA Astrophysics Data System (ADS)

    Fried, William A.; Chan, Kenneth H.; Darling, Cynthia L.; Fried, Daniel

    2016-02-01

    Selective removal of dental composite with high precision is best accomplished using lasers operating at high pulse repetition rates focused to a small spot size. Conventional flash-lamp pumped Er:YAG lasers are poorly suited for this purpose, but new diode-pumped Er:YAG lasers have become available operating at high pulse repetition rates. The purpose of this study was to compare the ablation rates and selectivity of enamel and composite for a 30 W diode-pumped Er:YAG laser operating with a pulse duration of 30-50-μs and evaluate it's suitability for the selective removal of composite from tooth surfaces. The depth of ablation and changes in surface morphology were assessed using digital microscopy. The fluence range of 30-50 J/cm2 appeared optimal for the removal of composite, and damage to sound enamel was limited to less than 100-μm after the removal of composite as thick as 700-800-μm. Future studies will focus on the use of methods of feedback to further increase selectivity.

  12. Selective removal of dental composite with a diode-pumped Er:YAG laser

    PubMed Central

    Fried, William A.; Chan, Kenneth H.; Darling, Cynthia L.; Fried, Daniel

    2016-01-01

    Selective removal of dental composite with high precision is best accomplished using lasers operating at high pulse repetition rates focused to a small spot size. Conventional flash-lamp pumped Er:YAG lasers are poorly suited for this purpose, but new diode-pumped Er:YAG lasers have become available operating at high pulse repetition rates. The purpose of this study was to compare the ablation rates and selectivity of enamel and composite for a 30 W diode-pumped Er:YAG laser operating with a pulse duration of 30–50-μs and evaluate it’s suitability for the selective removal of composite from tooth surfaces. The depth of ablation and changes in surface morphology were assessed using digital microscopy. The fluence range of 30–50 J/cm2 appeared optimal for the removal of composite, and damage to sound enamel was limited to less than 100-μm after the removal of composite as thick as 700–800-μm. Future studies will focus on the use of methods of feedback to further increase selectivity. PMID:26997741

  13. 49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... specifications in FMVSS No. 108 (49 CFR 571.108), SAE J581, and SAE J583, respectively. ... § 393.11(a). The headlamps shall provide an upper and lower beam distribution of light, selectable at... of the required headlamps. Auxiliary driving lamps shall meet SAE Standard J581 Auxiliary Upper...

  14. 49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... specifications in FMVSS No. 108 (49 CFR 571.108), SAE J581, and SAE J583, respectively. ... § 393.11(a). The headlamps shall provide an upper and lower beam distribution of light, selectable at... of the required headlamps. Auxiliary driving lamps shall meet SAE Standard J581 Auxiliary Upper...

  15. 49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... specifications in FMVSS No. 108 (49 CFR 571.108), SAE J581, and SAE J583, respectively. ... § 393.11(a). The headlamps shall provide an upper and lower beam distribution of light, selectable at... of the required headlamps. Auxiliary driving lamps shall meet SAE Standard J581 Auxiliary Upper...

  16. 49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... specifications in FMVSS No. 108 (49 CFR 571.108), SAE J581, and SAE J583, respectively. ... § 393.11(a). The headlamps shall provide an upper and lower beam distribution of light, selectable at... of the required headlamps. Auxiliary driving lamps shall meet SAE Standard J581 Auxiliary Upper...

  17. Methods for reducing the divergence of lamp-excited rhodamine 6G solution lasers

    SciTech Connect

    Smirnov, V.S.

    1980-11-01

    Different methods for reducing the divergence of rhodamine 6G solution lasers with lamp pumping are studied experimentally. A reduction of divergence to 2--4 mrad is achieved. It is shown that some methods provide such low divergence for comparatively low losses of lasing energy.

  18. Theory of optical flashes

    SciTech Connect

    London, R.A.

    1983-09-30

    The theory of optical flashes created by x- and ..gamma..-ray burst heating of stars in binaries is reviewed. Calculations of spectra due to steady-state x-ray reprocessing and estimates of the fundamental time scales for the non-steady case are discussed. The results are applied to the extant optical data from x-ray and ..gamma..-ray bursters. Finally, I review predictions of flashes from ..gamma..-ray bursters detectable by a state of the art all-sky optical monitor.

  19. Evaluating fluorescent lamp options under EPACT

    SciTech Connect

    Palko, E.

    1994-02-01

    The National Energy Policy Act (EPACT) sweeps the full spectrum of energy use in all forms, prescribing minimum efficiency standards for energy-consuming products. Notable among the products covered under EPACT are general-purpose fluorescent lamps commonly used to illuminate manufacturing, storage, laboratory, and office areas of industrial plants. Some specialty fluorescent lamp categories are exempt from the provisions of EPACT. Included in this specialty group are plant-growth, reflectorized or aperture, colored, reprographic, cold-temperature, and impact-resistant lamps. EPACT decrees moratorium dates on the manufacture of many types of lamps in common use in plants today. Lamps proscribed by EPACT, and their effective manufacturing cutoff dates, are given in the accompanying section, Fluorescent Lamps Outlawed Under EPACT. Noncomplying lamps, however, are permitted to remain in service, and can continue to be sold until stock is depleted. This paper explains the provisions of the Act.

  20. Microwave lamp with multi-purpose rotary motor

    DOEpatents

    Ury, Michael G.; Turner, Brian; Wooten, Robert D.

    1999-01-01

    In a microwave powered electrodeless lamp, a single rotary motor is used to a) rotate the bulb and b) provide rotary motion to a blower or pump means for providing cooling fluid to the magnetron and/or to a forced gas cooling for providing cooler gas to the bulb. The blower may consist of only of an impeller without the usual blower housing. The motor, bulb stem and bulb, or motor, bulb stem, bulb and blower may be formed as an integral unit so as to facilitate replacement.

  1. Microwave lamp with multi-purpose rotary motor

    DOEpatents

    Ury, M.G.; Turner, B.; Wooten, R.D.

    1999-02-02

    In a microwave powered electrodeless lamp, a single rotary motor is used to (a) rotate the bulb and (b) provide rotary motion to a blower or pump means for providing cooling fluid to the magnetron and/or to a forced gas cooler for providing cooling gas to the bulb. The blower may consist of only of an impeller without the usual blower housing. The motor, bulb stem and bulb, or motor, bulb stem, bulb and blower may be formed as an integral unit so as to facilitate replacement. 8 figs.

  2. A flash photographic method for droplet impingement studies

    SciTech Connect

    Hart, V.

    1999-07-01

    This paper describes an experimental method to visualize the impingement process of a liquid droplet onto a solid surface with sufficient clarity to reveal fine details of the droplet surface structure and rim jet produced during the impingement process. The method incorporates a 35 mm SLR camera with bellows, motor drive, macro lens, backlighting by a short duration flash lamp, diffusers and a commercially available timing control unit to trigger the flash. Results using the experimental arrangement are demonstrated for a water droplet striking a horizontal surface at a velocity of about 1 m/s, though the photographic method may be applied to any other condition and liquid. A series of photographs are presented that show the repeatability of the impingement process, image clarity, surface structure of the droplet during impingement.

  3. Flashing anomalous color contrast.

    PubMed

    Pinna, Baingio; Spillmann, Lothar; Werner, John S

    2004-01-01

    A new visual phenomenon that we call flashing anomalous color contrast is described. This phenomenon arises from the interaction between a gray central disk and a chromatic annulus surrounded by black radial lines. In an array of such figures, the central gray disk no longer appears gray, but assumes a color complementary to that of the surrounding annulus. The induced color appears: (1) vivid and saturated; (2) self-luminous, not a surface property; (3) flashing with eye or stimulus movement; (4) floating out of its confines; and (5) stronger in extrafoveal than in foveal vision. The strength of the effect depends on the number, length, width, and luminance contrast of the radial lines. The results suggest that the chromatic ring bounding the inner tips of the black radial lines induces simultaneous color contrast, whereas the radial lines elicit, in conjunction with the gray disk and the ring, the flashing, vividness, and high saturation of the effect. The stimulus properties inducing the illusion suggest that flashing anomalous color contrast may be based on asynchronous interactions among multiple visual pathways. PMID:15518215

  4. Measuring and Estimating Normalized Contrast in Infrared Flash Thermography

    NASA Technical Reports Server (NTRS)

    Koshti, Ajay M.

    2013-01-01

    Infrared flash thermography (IRFT) is used to detect void-like flaws in a test object. The IRFT technique involves heating up the part surface using a flash of flash lamps. The post-flash evolution of the part surface temperature is sensed by an IR camera in terms of pixel intensity of image pixels. The IR technique involves recording of the IR video image data and analysis of the data using the normalized pixel intensity and temperature contrast analysis method for characterization of void-like flaws for depth and width. This work introduces a new definition of the normalized IR pixel intensity contrast and normalized surface temperature contrast. A procedure is provided to compute the pixel intensity contrast from the camera pixel intensity evolution data. The pixel intensity contrast and the corresponding surface temperature contrast differ but are related. This work provides a method to estimate the temperature evolution and the normalized temperature contrast from the measured pixel intensity evolution data and some additional measurements during data acquisition.

  5. Lamp with a truncated reflector cup

    DOEpatents

    Li, Ming; Allen, Steven C.; Bazydola, Sarah; Ghiu, Camil-Daniel

    2013-10-15

    A lamp assembly, and method for making same. The lamp assembly includes first and second truncated reflector cups. The lamp assembly also includes at least one base plate disposed between the first and second truncated reflector cups, and a light engine disposed on a top surface of the at least one base plate. The light engine is configured to emit light to be reflected by one of the first and second truncated reflector cups.

  6. The low-pressure sodium lamp

    SciTech Connect

    Hooker, J.D.

    1997-12-31

    For many years before the introduction of the sodium vapor lamp, scientists had been aware of the remarkably high luminous efficacy of the sodium discharge. However, many technical problems had to be overcome before these lamps could be marketed. The first commercial low pressure sodium lamps were introduced in the early 1930s and to this day they remain the most efficient light sources available. The high efficacy is due partly to the fact that these lamps emit nearly monochromatic yellow light, which is very close to the peak sensitivity of the human eye. Sodium lamps have come a long way since their introduction, and efficacies are now approaching 200 lumens per watt. Despite increasing competition from other types of discharge lamp, low pressure sodium lamps of the SOX type find widespread use in road and security lighting, particularly in Great Britain and many other parts of Europe. This paper reviews the operation and development of the low pressure sodium lamp, and shows what makes it different from the many other types of discharge lamp available.

  7. 30 CFR 20.9 - Class 2 lamps.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Class 2 lamps. 20.9 Section 20.9 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MINE LAMPS OTHER THAN STANDARD CAP LAMPS § 20.9 Class 2 lamps. (a) Safety. (1) Unless special features of the lamp...

  8. Lamp bulb with integral reflector

    DOEpatents

    Levin, Izrail; Shanks, Bruce; Sumner, Thomas L.

    2001-01-01

    An improved electrodeless discharge lamp bulb includes an integral ceramic reflector as a portion of the bulb envelope. The bulb envelope further includes two pieces, a reflector portion or segment is cast quartz ceramic and a light transmissive portion is a clear fused silica. In one embodiment, the cast quartz ceramic segment includes heat sink fins or stubs providing an increased outside surface area to dissipate internal heat. In another embodiment, the quartz ceramic segment includes an outside surface fused to eliminate gas permeation by polishing.

  9. Flash Lidar Data Processing

    NASA Astrophysics Data System (ADS)

    Bergkoetter, M. D.; Ruppert, L.; Weimer, C. S.; Ramond, T.; Lefsky, M. A.; Burke, I. C.; Hu, Y.

    2009-12-01

    Late last year, a prototype Flash LIDAR instrument flew on a series of airborne tests to demonstrate its potential for improved vegetation measurements. The prototype is a precursor to the Electronically Steerable Flash LIDAR (ESFL) currently under development at Ball Aerospace and Technology Corp. with funding from the NASA Earth Science Technology Office. ESFL may soon significantly expand our ability to measure vegetation and forests and better understand the extent of their role in global climate change and the carbon cycle - all critical science questions relating to the upcoming NASA DESDynI and ESA BIOMASS missions. In order to more efficiently exploit data returned from the experimental Flash Lidar system and plan for data exploitation from future flights, Ball funded a graduate student project (through the Ball Summer Intern Program, summer 2009) to develop and implement algorithms for post-processing of the 3-Dimensional Flash Lidar data. This effort included developing autonomous algorithms to resample the data to a uniform rectangular grid, geolocation of the data, and visual display of large swaths of data. The resampling, geolocation, surface hit detection, and aggregation of frame data are implemented with new MATLAB code, and the efficient visual display is achieved with free commercial viewing software. These efforts directly support additional tests flights planned as early as October 2009, including possible flights over Niwot Ridge, CO, for which there is ICESat data, and a sea-level coastal area in California to test the effect of higher altitude (above ground level) on the divergence of the beams and the beam spot sizes.

  10. 10 CFR 429.27 - General service fluorescent lamps, general service incandescent lamps, and incandescent reflector...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false General service fluorescent lamps, general service incandescent lamps, and incandescent reflector lamps. 429.27 Section 429.27 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification §...

  11. Effective Fluorescence Lifetime and Stimulated Emission Cross-Section of Nd/Cr:YAG Ceramics under CW Lamplight Pumping

    NASA Astrophysics Data System (ADS)

    Saiki, Taku; Motokoshi, Shinji; Imasaki, Kazuo; Fujioka, Kana; Fujita, Hisanori; Nakatsuka, Masahiro; Izawa, Yasukazu; Yamanaka, Chiyoe

    2008-10-01

    Remarkable improvements in the lifetime of the Nd upper level and in the effective stimulated emission cross-section of Nd/Cr:YAG ceramics have been theoretically and experimentally studied. Until recently, it had been thought that the long energy transition time from Cr ions to Nd ions of Nd/Cr:YAG adversely affects laser action, degrading optical-optical conversion efficiency under CW and flash lamp pumping. However, current research showed that high-efficiency energy transition has a positive effect on laser action. The effective lifetime is increased from 0.23 to 1.1 ms and the emission cross-section is effectively increased to three times for that of the conventional Nd:YAG. A small signal gain is significantly improved, and the saturation power density is reduced to 1/10 that of the Nd:YAG for the same pumping power density. A CW laser light generated in a laser diode (LD)-pumped 1064 nm Nd:YAG laser oscillator was amplified, and the measured output power was saturated. The output laser power calculated using theoretical saturation power density was consistent with the experimental results.

  12. Investigations on the potential of a low power diode pumped Er:YAG laser system for oral surgery

    NASA Astrophysics Data System (ADS)

    Stock, Karl; Wurm, Holger; Hausladen, Florian; Wagner, Sophia; Hibst, Raimund

    2015-02-01

    Flash lamp pumped Er:YAG-lasers are used in clinical practice for dental applications successfully. As an alternative, several diode pumped Er:YAG laser systems (Pantec Engineering AG) become available, with mean laser power of 2W, 15W, and 30W. The aim of the presented study is to investigate the potential of the 2W Er:YAG laser system for oral surgery. At first an appropriate experimental set-up was realized with a beam delivery and both, a focusing unit for non-contact tissue cutting and a fiber tip for tissue cutting in contact mode. In order to produce reproducible cuts, the samples (porcine gingiva) were moved by a computer controlled translation stage. On the fresh samples cutting depth and quality were determined by light microscopy. Afterwards histological sections were prepared and microscopically analyzed regarding cutting depth and thermal damage zone. The experiments show that low laser power ≤ 2W is sufficient to perform efficient oral soft tissue cutting with cut depth up to 2mm (sample movement 2mm/s). The width of the thermal damage zone can be controlled by the irradiation parameters within a range of about 50μm to 110μm. In general, thermal injury is more pronounced using fiber tips in contact mode compared to the focused laser beam. In conclusion the results reveal that even the low power diode pumped Er:YAG laser is an appropriate tool for oral surgery.

  13. Optimal flash rate and duty cycle for flashing visual indicators.

    NASA Technical Reports Server (NTRS)

    Markowitz, J.

    1971-01-01

    This experiment examined the ability of observers to determine, as quickly as possible, whether a visual indicator was steadily on or flashing. Six flash rates (periods) were combined factorially with three duty cycles (on-off ratios) to define 18 ?types' of intermittent signals. Experimental sessions were divided into six runs of 100 trials, each run utilizing one of the six flash rates. On any given trial in a run, the probability of a steady signal occurring was 0.5 and the probability of a flashing signal occurring was 0.5. A different duty cycle was employed daily for each experimental session. In all, 400 trials were devoted to each of the flash rates at each duty cycle. Accuracy and latency of response were the dependent variables of interest. The results show that the observers view the light for an interval of time appropriate to the expected flash rate and duty cycle; whether they judge the light to be steady or intermittent depends upon whether the light is extinguished during the predetermined waiting period. Adoption of this temporal criterion delays responding in comparison to those tasks involving responses to light onset. The decision or response criteria held by the observers are also sensitive to the parameters of the flashing light: observers become increasingly willing to call a flashing light ?steady' as flash duration increases.

  14. Discharge lamp with reflective jacket

    DOEpatents

    MacLennan, Donald A.; Turner, Brian P.; Kipling, Kent

    2001-01-01

    A discharge lamp includes an envelope, a fill which emits light when excited disposed in the envelope, a source of excitation power coupled to the fill to excite the fill and cause the fill to emit light, and a reflector disposed around the envelope and defining an opening, the reflector being configured to reflect some of the light emitted by the fill back into the fill while allowing some light to exit through the opening. The reflector may be made from a material having a similar thermal index of expansion as compared to the envelope and which is closely spaced to the envelope. The envelope material may be quartz and the reflector material may be either silica or alumina. The reflector may be formed as a jacket having a rigid structure which does not adhere to the envelope. The lamp may further include an optical clement spaced from the envelope and configured to reflect an unwanted component of light which exited the envelope back into the envelope through the opening in the reflector. Light which can be beneficially recaptured includes selected wavelength regions, a selected polarization, and selected angular components.

  15. PNNL 331 Building Arc Flash Team Investigation Report

    SciTech Connect

    Deichman, Mark L.; Drewrey, John C.; Hodges, Hurtis; Madson, Vernon J.; Minton, Allen L.; Montgomery, Daniel M.; Olson, Marvin E.; Rojas, Pedro H.; Sanan, Sanjay K.; Sharp, Reed D.; Sparks, Bobby R.; Swearingen, Gary L.

    2006-06-06

    On Friday, April 21, 2006, a PNNL electrician was performing repair of an electrical system for the 331 Building chilled water pump (CHWP) No.2, when an electrical arc flash occurred inside a 480V combination motor starter. The electrician was taken to the on-site medical provider for evaluation and was released for return to work without restriction. The electrician was not shocked, but did receive a minor, superficial (first degree) burn on the left wrist. This report, the result of a thorough review by the 331 Building Arc Flash Assessment Team, provides an in-depth look at the steps leading up to the arc-flash and recommendations and opportunities for improvement.

  16. 200-W InGaAlAs/GaAs diode laser bars for pumping

    NASA Astrophysics Data System (ADS)

    Acklin, Bruno D.; Behringer, Martin; Herrmann, Gerhard; Luft, Johann; Hanke, Christian; Korte, Lutz; Marchiano, Marcel; Wilhelmi, Jens; De Odorico, B.

    2000-04-01

    Solid state laser pumping is an important application for high power semiconductor lasers. The higher electro-optical conversion efficiency (50%), and narrower spectral emission (2 - 5 nm) of laser diodes allow for more efficient pumping compared to flash lamps, and consequently lead to superior thermal and optical properties of the solid state laser. A further performance increase and thus price reduction, especially for pulsed and qcw operation, is conceivable using a promising approach proposed almost 20 years ago which we dubbed 'micro-stack lasers.' It consists in vertically integrating multiple active laser junctions in one -- structure using degenerately doped tunnel junctions to electrically connect the intermediate reverse junctions. By stacking 2 to 4 emitters in this way, the output power of semiconductor lasers could theoretically be increased by a factor of 2 to 4 as the reliable output power is mainly limited by the power density at the laser facets. Modern growth technology can provide the necessary 10 to 20 micrometer thick high quality epitaxial layers. The limiting factors rather originate from the additional electrical and thermal resistance, and from current spreading towards the deeper junctions.

  17. Loop-Mediated Isothermal Amplification (LAMP) Signature Identification Software

    Energy Science and Technology Software Center (ESTSC)

    2009-03-17

    This is an extendable open-source Loop-mediated isothermal AMPlification (LAMP) signature design program called LAVA (LAMP Assay Versatile Analysis). LAVA was created in response to limitations of existing LAMP signature programs.

  18. Laser flash effects on laser speckle shift visual evoked potential.

    PubMed

    Schmeisser, E T

    1985-10-01

    Steady-state visual evoked potentials (VEP's) were recorded from four cynomolgus monkeys in response to a sinusoidally oscillating 10 degrees helium-neon laser speckle field (632.8 nm), moving vertically 2.5 degrees at 8 shifts per second. A 5-pulse flash train at the maximum permissible exposure (MPE) dose from a collimated Q-switched frequency-doubled neodymium laser (532 nm) was superimposed on the foveal stimulus and the subsequent disruption and recovery of the VEP measured. Minimal disruption of the response signal magnitude was demonstrated (0.1 greater than p greater than 0.05) which recovered within 300 ms of the termination of the pulse train. A small but significant (p less than 0.01) disruption of phase entrainment was also noted that recovered within the same period. This is contrasted with a second experiment with three monkeys in which an argon (514 nm) laser served both as the speckle stimulus source and as the shuttered flash. Exposure to collimated MPE argon radiation for 250 ms immediately depressed the VEP (97%, p less than 0.01) and showed recovery to 70% of the pre-flash baseline only after 3 s. Phase lock was also severely degraded for several seconds. These results imply that visual processing of nonacuity-limited medium contrast stimuli with broad spatial frequency content will probably not be materially affected by ultra-short pulsed laser exposure at these energy levels and frequencies. However, even safe levels of collimated continuous laser light may have severe effects on vision that could parallel flash effects seen with Xenon discharge flash lamps. PMID:4073205

  19. General service incandescent lamp with improved efficiency

    SciTech Connect

    Berlec, I.

    1985-06-18

    A high efficiency general service incandescent lamp is disclosed. The disclosed improved general service incandescent lamp has an outer and an inner envelope. The inner envelope has a relatively small housing containing a halogen gas and a relatively high pressure efficient fill-gas and in which a low voltage filament is spatially disposed therein.

  20. Temperature and Color of Incandescent Lamps.

    ERIC Educational Resources Information Center

    Wagner, William S.

    1991-01-01

    Two different methods of measuring the temperature of an incandescent lamp at various voltage levels are described. By observing the color produced at a particular voltage levels, the lamp's color as a function of temperature can be determined. Needed equipment include a variac, a voltmeter, and an ammeter. (KR)

  1. Lamp modulator provides signal magnitude indication

    NASA Technical Reports Server (NTRS)

    Zeman, J. R.

    1970-01-01

    Lamp modulator provides visible indication of presence and magnitude of an audio signal carrying voice or data. It can be made to reflect signal variations of up to 32 decibels. Lamp life is increased by use of a bypass resistor to prevent filament failure.

  2. 21 CFR 878.4580 - Surgical lamp.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Surgical lamp. 878.4580 Section 878.4580 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4580 Surgical lamp. (a) Identification....

  3. 21 CFR 878.4580 - Surgical lamp.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Surgical lamp. 878.4580 Section 878.4580 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4580 Surgical lamp. (a) Identification....

  4. 21 CFR 878.4580 - Surgical lamp.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Surgical lamp. 878.4580 Section 878.4580 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4580 Surgical lamp. (a) Identification....

  5. 21 CFR 878.4580 - Surgical lamp.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Surgical lamp. 878.4580 Section 878.4580 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4580 Surgical lamp. (a) Identification....

  6. 21 CFR 878.4580 - Surgical lamp.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Surgical lamp. 878.4580 Section 878.4580 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4580 Surgical lamp. (a) Identification....

  7. Primer of School Lighting Lamps and Maintenance.

    ERIC Educational Resources Information Center

    Allphin, Willard

    The basic principles of the most commonly used lamp types and the circuitry which makes them operate are discussed. The two objectives of this book are to serve as a--(1) guide to economical lighting, and (2) a permanent reference source for troubleshooting. Areas dealt with include--(1) lighting fundamentals, (2) incandescent lamps, (3)…

  8. Gun muzzle blast and flash

    NASA Astrophysics Data System (ADS)

    Klingenberg, Guenter; Heimerl, Joseph M.

    A repository of fundamental experimental and analytical data concerning the complex phenomena associated with gun-muzzle blast and flash effects is presented, proceeding from gun muzzle signatures to modern gun-propulsion concepts, interior and transitional ballistics, and characterizations of blast-wave research and muzzle flash. Data are presented in support of a novel hypothesis which explains the ignition of secondary flash and elucidates the means for its suppression. Both chemical and mechanical (often competing) methods of flash suppression are treated. The historical work of Kesslau and Ladenburg is noted, together with French, British, Japanese and American research efforts and current techniques of experimental characterization for gun muzzle phenomena.

  9. High efficiency fluorescent excimer lamps: An alternative to mercury based UVC lamps

    SciTech Connect

    Masoud, N. M.; Murnick, D. E.

    2013-12-15

    A high efficiency xenon excimer lamp radiating at 172 nm, with an internal phosphor coating shifting to UVC has been demonstrated, showing the feasibility of a cost effective alternative to UVC mercury lamps. Fluorescent lamps so designed can be fabricated in various geometries with high efficiency. Unlike other xenon excimer lamps based on dielectric barrier discharges this new system is highly compatible with existing and proposed phosphors as it operates in an inert gas environment at modest temperature and is subject only to 172 nm primary radiation. Using a lamp coated with a UVC phosphor we have demonstrated the feasibility of germicidal and curing lamps with 40% energy conversion efficiency and high power density. These lamps are rapidly switchable, have long projected lifetimes and are compatible with dimmers.

  10. High efficiency fluorescent excimer lamps: an alternative to mercury based UVC lamps.

    PubMed

    Masoud, N M; Murnick, D E

    2013-12-01

    A high efficiency xenon excimer lamp radiating at 172 nm, with an internal phosphor coating shifting to UVC has been demonstrated, showing the feasibility of a cost effective alternative to UVC mercury lamps. Fluorescent lamps so designed can be fabricated in various geometries with high efficiency. Unlike other xenon excimer lamps based on dielectric barrier discharges this new system is highly compatible with existing and proposed phosphors as it operates in an inert gas environment at modest temperature and is subject only to 172 nm primary radiation. Using a lamp coated with a UVC phosphor we have demonstrated the feasibility of germicidal and curing lamps with 40% energy conversion efficiency and high power density. These lamps are rapidly switchable, have long projected lifetimes and are compatible with dimmers. PMID:24387421

  11. Optimized design of LED plant lamp

    NASA Astrophysics Data System (ADS)

    Chen, Jian-sheng; Cai, Ruhai; Zhao, Yunyun; Zhao, Fuli; Yang, Bowen

    2014-12-01

    In order to fabricate the optimized LED plant lamp we demonstrated an optical spectral exploration. According to the mechanism of higher plant photosynthesis process and the spectral analysis we demonstrate an optical design of the LED plant lamp. Furthermore we built two kins of prototypes of the LED plant lamps which are suitable for the photosynthesis of higher green vegetables. Based on the simulation of the lamp box of the different alignment of the plants we carried out the growing experiment of green vegetable and obtain the optimized light illumination as well as the spectral profile. The results show that only blue and red light are efficient for the green leave vegetables. Our work is undoubtedly helpful for the LED plant lamping design and manufacture.

  12. Portable lamp with dynamically controlled lighting distribution

    DOEpatents

    Siminovitch, Michael J.; Page, Erik R.

    2001-01-01

    A double lamp table or floor lamp lighting system has a pair of compact fluorescent lamps (CFLs) arranged vertically with a reflective septum in between. By selectively turning on one or both of the CFLs, down lighting, up lighting, or both up and down lighting is produced. The control system can also vary the light intensity from each CFL. The reflective septum insures that almost all the light produced by each lamp will be directed into the desired light distribution pattern which is selected and easily changed by the user. Planar compact fluorescent lamps, e.g. circular CFLs, particularly oriented horizontally, are preferable. CFLs provide energy efficiency. The lighting system may be designed for the home, hospitality, office or other environments.

  13. Optimization of white polychromatic semiconductor lamps

    NASA Astrophysics Data System (ADS)

    Žukauskas, A.; Vaicekauskas, R.; Ivanauskas, F.; Gaska, R.; Shur, M. S.

    2002-01-01

    A stochastic method of optimization of a white-light source that relies on additive color mixing of the emissions from colored light-emitting diodes (LEDs) was developed. The method allows for finding the optimal wavelengths of LEDs in order to obtain the best possible trade off between luminous efficacy and the general color rendering index (CRI) of the white source for an arbitrary number of primary LEDs. Optimal solid-state lamps composed of two, three, four, and five different LEDs were analyzed. We show that a dichromatic LED lamp can only provide high efficacy with a general CRI close to zero, whereas trichromatic and quadrichromatic lamps are able to cover the entire range of reasonable general CRI values. The optimization of quintichromatic LED lamps and lamps with a higher number of primary color LEDs yields a negligible benefit in improving CRI but provides for quasicontinuous spectra that might be required for special lighting needs.

  14. Flash Proton Radiography

    NASA Astrophysics Data System (ADS)

    Merrill, Frank E.

    Protons were first investigated as radiographic probes as high energy proton accelerators became accessible to the scientific community in the 1960s. Like the initial use of X-rays in the 1800s, protons were shown to be a useful tool for studying the contents of opaque materials, but the electromagnetic charge of the protons opened up a new set of interaction processes which complicated their use. These complications in combination with the high expense of generating protons with energies high enough to penetrate typical objects resulted in proton radiography becoming a novelty, demonstrated at accelerator facilities, but not utilized to their full potential until the 1990s at Los Alamos. During this time Los Alamos National Laboratory was investigating a wide range of options, including X-rays and neutrons, as the next generation of probes to be used for thick object flash radiography. During this process it was realized that the charge nature of the protons, which was the source of the initial difficulty with this idea, could be used to recover this technique. By introducing a magnetic imaging lens downstream of the object to be radiographed, the blur resulting from scattering within the object could be focused out of the measurements, dramatically improving the resolution of proton radiography of thick systems. Imaging systems were quickly developed and combined with the temporal structure of a proton beam generated by a linear accelerator, providing a unique flash radiography capability for measurements at Los Alamos National Laboratory. This technique has now been employed at LANSCE for two decades and has been adopted around the world as the premier flash radiography technique for the study of dynamic material properties.

  15. Dispenser printed electroluminescent lamps on textiles for smart fabric applications

    NASA Astrophysics Data System (ADS)

    de Vos, Marc; Torah, Russel; Tudor, John

    2016-04-01

    Flexible electroluminescent (EL) lamps are fabricated onto woven textiles using a novel dispenser printing process. Dispenser printing utilizes pressurized air to deposit ink onto a substrate through a syringe and nozzle. This work demonstrates the first use of this technology to fabricate EL lamps. The luminance of the dispenser printed EL lamps is compared to screen-printed EL lamps, both printed on textile, and also commercial EL lamps on polyurethane film. The dispenser printed lamps are shown to have a 1.5 times higher luminance than the best performing commercially available lamp, and have a comparable performance to the screen-printed lamps.

  16. Methods of flash sintering

    DOEpatents

    Raj, Rishi; Cologna, Marco; Francis, John S.

    2016-05-10

    This disclosure provides methods of flash sintering and compositions created by these methods. Methods for sintering multilayered bodies are provided in which a sintered body is produced in less than one minute. In one aspect, each layer is of a different composition, and may be constituted wholly from a ceramic or from a combination of ceramic and metallic particles. When the body includes a layer of an anode composition, a layer of an electrolyte composition and a layer of a cathode composition, the sintered body can be used to produce a solid oxide fuel cell.

  17. Flash evaporator systems test

    NASA Technical Reports Server (NTRS)

    Dietz, J. B.

    1976-01-01

    A flash evaporator heat rejection system representative of that proposed for the space shuttle orbiter underwent extensive system testing at the NASA Johnson Space Center (JSC) to determine its operational suitability and to establish system performance/operational characteristics for use in the shuttle system. During the tests the evaporator system demonstrated its suitability to meet the shuttle requirements by: (1) efficient operation with 90 to 95% water evaporation efficiency, (2) control of outlet temperature to 40 + or - 2 F for partial heat load operation, (3) stability of control system for rapid changes in Freon inlet temperature, and (4) repeated dormant-to-active device operation without any startup procedures.

  18. Laboratory prototype flash evaporator

    NASA Technical Reports Server (NTRS)

    Gaddis, J. L.

    1972-01-01

    A laboratory prototype flash evaporator that is being developed as a candidate for the space shuttle environmental control system expendable heat sink is described. The single evaporator configuration uses water as an evaporant to accommodate reentry and on-orbit peak heat loads, and Freon 22 for terrestrial flight phases below 120,000 feet altitude. The design features, fabrication techniques used for the prototype unit, redundancy considerations, and the fluid temperature control arrangement are reported in detail. The results of an extensive test program to determine the evaporator operational characteristics under a wide variety of conditions are presented.

  19. Network of LAMP systems for atmospheric monitoring in India

    NASA Astrophysics Data System (ADS)

    Yellapragada, Bhavani Kumar; Jayaraman, Achuthan

    2012-07-01

    A systematic knowledge of the vertical distribution of aerosol particles in the atmosphere is required for understanding many atmospheric processes such as dynamics of boundary layer, pollution transport, modification of cloud microphysics etc. At present, the information on the particle distribution in the atmosphere is far from sufficient to estimate properly the load of aerosols in the atmosphere. Light detection and ranging (LIDAR) has been demonstrated to be a reliable remote sensing technique to obtain altitude profiles of atmospheric cloud and aerosol scattering. A LIDAR network is being implemented by National Atmospheric Research Laboratory (NARL), a Department of Space unit, in India for the measurement and monitoring of the atmospheric aerosols and clouds. Towards this, the technology of boundary layer lidar (BLL) (Bhavani Kumar, 2006) has been exploited. Several industrial grade BLL systems are being fabricated at a private industry in India through technological transfer from NARL. The industrial BLL lidar is named as LAMP, stands for LIDAR for Atmospheric Measurement and Probing. Five LAMP systems have already been fabricated and deployed at several locations of the country for continuous monitoring of aerosols and clouds under the Indian Lidar network (I-LINK) programme. The LAMP system employs a single barrel construction so that no realignment is required in future. Moreover, the network lidar system employs several features like rotation facility about the elevation (EL) axis, a provision of front window for environmental protection to the telescope optics and a silica gel pocket for desiccation (for transmit and receive assembly) and a provision of nitrogen purging to overcome the humidity effects. The LAMP system is an autonomous system equipped with a diode pumped Nd-YAG laser, a PMT for the detection of the backscattered photons, and a PC based photon counting electronics for recording the photon returns. In this paper, a report describing

  20. NAND FLASH Radiation Tolerant Intelligent Memory Stack (RTIMS FLASH)

    NASA Astrophysics Data System (ADS)

    Sellier, Charles; Wang, Pierre

    2014-08-01

    The NAND Flash Radiation Tolerant and Intelligent Memory Stack (RTIMS FLASH) is a User's Friendly, Plug-and- Play and Radiation Protected high density NAND Flash Memory. It provides a very high density, radiation hardened by design and non-volatile memory module suitable for all space applications such as commercial or scientific geo-stationary missions, earth observation, navigation, manned space vehicles and deep space scientific exploration. The Intelligent Memory Module embeds a very high density of non-volatile NAND Flash memory and one Intelligent Flash Memory Controller (FMC). The FMC provides the module with a full protection against the radiation effects such as SEL, SEFI and SEU. It's also granting the module with bad block immunity as well as high level service functions that will benefit to the user's applications.

  1. FLASH: a rapid method for prototyping paper-based microfluidic devices.

    PubMed

    Martinez, Andres W; Phillips, Scott T; Wiley, Benjamin J; Gupta, Malancha; Whitesides, George M

    2008-12-01

    This article describes FLASH (Fast Lithographic Activation of Sheets), a rapid method for laboratory prototyping of microfluidic devices in paper. Paper-based microfluidic devices are emerging as a new technology for applications in diagnostics for the developing world, where low cost and simplicity are essential. FLASH is based on photolithography, but requires only a UV lamp and a hotplate; no clean-room or special facilities are required (FLASH patterning can even be performed in sunlight if a UV lamp and hotplate are unavailable). The method provides channels in paper with dimensions as small as 200 microm in width and 70 microm in height; the height is defined by the thickness of the paper. Photomasks for patterning paper-based microfluidic devices can be printed using an ink-jet printer or photocopier, or drawn by hand using a waterproof black pen. FLASH provides a straightforward method for prototyping paper-based microfluidic devices in regions where the technological support for conventional photolithography is not available. PMID:19023478

  2. FLASH: A rapid method for prototyping paper-based microfluidic devices‡

    PubMed Central

    Martinez, Andres W.; Phillips, Scott T.; Wiley, Benjamin J.; Gupta, Malancha

    2011-01-01

    This article describes FLASH (Fast Lithographic Activation of Sheets), a rapid method for laboratory prototyping of microfluidic devices in paper. Paper-based microfluidic devices are emerging as a new technology for applications in diagnostics for the developing world, where low cost and simplicity are essential. FLASH is based on photolithography, but requires only a UV lamp and a hotplate; no clean-room or special facilities are required (FLASH patterning can even be performed in sunlight if a UV lamp and hotplate are unavailable). The method provides channels in paper with dimensions as small as 200 μm in width and 70 μm in height; the height is defined by the thickness of the paper. Photomasks for patterning paper-based microfluidic devices can be printed using an ink-jet printer or photocopier, or drawn by hand using a waterproof black pen. FLASH provides a straightforward method for prototyping paper-based microfluidic devices in regions where the technological support for conventional photolithography is not available. PMID:19023478

  3. High concentration (2500 suns), high throughput, automated flash tester with calibrated color balance and intensity control

    NASA Astrophysics Data System (ADS)

    Ludowise, Michael; Taylor, Sean; Lucow, Ewelina; Chan, Hing

    2008-08-01

    SolFocus has designed and built a flexible and adaptable solar flash tester capable of reaching in excess of 2500x suns flux using a commercially available Xenon flash and power supply. Using calibrated isotype cells and photodetectors, the intensity and color balance of the flash are controlled through software algorithms that compensate for tube aging and thermal drift. The data acquisition system dynamically normalizes each of the 1600 I-V data pairs to the lamp intensity during each flash. Up to 32 cells can be measured simultaneously, with a flash re-cycle time of 3 seconds. The dynamic current range is 100μA to 10A over 0 to 5V. Test ranges are limited by user input through a modern GUI screen. The system is mated to a commercially available probe station tester which allows automated testing of up to 150mm diameter wafers, and is capable of testing a 4000 cell wafer in less than 8 minutes. The core software and optical components are easily adaptable to receiver and full panel testing as well. Data on the calibration and performance of the flash tester, the dynamic range achieved in test, and throughputs obtained during operation are presented.

  4. Flash xenon CPV simulator with low-cost elastic bent-trough mirrors

    NASA Astrophysics Data System (ADS)

    Yamada, Noboru; Okamoto, Kazuya; Ijiro, Toshikazu; Kiryu, Mitsugu; Yoshida, Takanori

    2013-09-01

    In the research and development of concentrator photovoltaic (CPV) systems, a highly collimated artificial sunlight source with a wide irradiated area is very helpful in the reliable evaluation of module efficiency and optical performance. To collimate the light, a conventional flash xenon CPV simulator uses an expensive large concave mirror. This paper introduces a new flash xenon CPV simulator that consists of two low-cost elastic bent-trough mirrors. The prototype simulator achieved an irradiance deviation of less than 10%, collimation of 0.228° - 0.330°, and good spectral matching at an irradiated area of 700 mm × 500 mm. The major drawback of the present concept is that the flash lamp must provide higher emissive power than the conventional method because of the light attenuation caused by the two reflections from the mirrors.

  5. Vacuum flash evaporated polymer composites

    DOEpatents

    Affinito, John D.; Gross, Mark E.

    1997-01-01

    A method for fabrication of polymer composite layers in a vacuum is disclosed. More specifically, the method of dissolving salts in a monomer solution, vacuum flash evaporating the solution, condensing the flash evaporated solution as a liquid film, and forming the condensed liquid film into a polymer composite layer on a substrate is disclosed.

  6. Vacuum flash evaporated polymer composites

    DOEpatents

    Affinito, J.D.; Gross, M.E.

    1997-10-28

    A method for fabrication of polymer composite layers in a vacuum is disclosed. More specifically, the method of dissolving salts in a monomer solution, vacuum flash evaporating the solution, condensing the flash evaporated solution as a liquid film, and forming the condensed liquid film into a polymer composite layer on a substrate is disclosed.

  7. Intensified phototherapy using daylight fluorescent lamps.

    PubMed

    De Carvalho, M; De Carvalho, D; Trzmielina, S; Lopes, J M; Hansen, T W

    1999-07-01

    Jaundice is a common reason for therapeutic intervention in newborn infants and phototherapy is effective treatment if enough light energy is delivered to a skin surface area of sufficient size. Narrow spectrum blue light is superior to white light, but in developing countries fluorescent blue lamps often have to be imported and are much more expensive than white lamps. We developed a phototherapy unit in which seven daylight fluorescent tubes are placed immediately under the floor of a transparent plexiglass crib. The efficacy of this unit, delivering approximately 19 microW/cm2/nm, was compared with that of two conventional phototherapy units using overhead lamps placed 35 cm above the infants. One unit used daylight fluorescent tubes and delivered approximately 4 microW/cm2/nm, the other unit used special blue fluorescent tubes and delivered approximately 22 microW/cm2/nm. Fifty-one infants were included in the analyses, all of them breastfed on demand. Serum bilirubin levels were determined spectrophotometrically at 0, 12 and 24 h. The decrement in serum bilirubin concentrations was significantly greater in infants undergoing phototherapy with the new device or with special blue lamps compared to conventional overhead daylight lamps (p < 0.001 both at 12 and at 24 h). We conclude that highly efficient phototherapy may be delivered with daylight fluorescent lamps placed in very close proximity to the patient. Thus, lack of access to expensive imported special blue lamps does not preclude delivery of effective phototherapy in developing countries. PMID:10447138

  8. Geometric Modelling of Octagonal Lamp Poles

    NASA Astrophysics Data System (ADS)

    Chan, T. O.; Lichti, D. D.

    2014-06-01

    Lamp poles are one of the most abundant highway and community components in modern cities. Their supporting parts are primarily tapered octagonal cones specifically designed for wind resistance. The geometry and the positions of the lamp poles are important information for various applications. For example, they are important to monitoring deformation of aged lamp poles, maintaining an efficient highway GIS system, and also facilitating possible feature-based calibration of mobile LiDAR systems. In this paper, we present a novel geometric model for octagonal lamp poles. The model consists of seven parameters in which a rotation about the z-axis is included, and points are constrained by the trigonometric property of 2D octagons after applying the rotations. For the geometric fitting of the lamp pole point cloud captured by a terrestrial LiDAR, accurate initial parameter values are essential. They can be estimated by first fitting the points to a circular cone model and this is followed by some basic point cloud processing techniques. The model was verified by fitting both simulated and real data. The real data includes several lamp pole point clouds captured by: (1) Faro Focus 3D and (2) Velodyne HDL-32E. The fitting results using the proposed model are promising, and up to 2.9 mm improvement in fitting accuracy was realized for the real lamp pole point clouds compared to using the conventional circular cone model. The overall result suggests that the proposed model is appropriate and rigorous.

  9. Primary investigations on the potential of a novel diode pumped Er:YAG laser system for middle ear surgery

    NASA Astrophysics Data System (ADS)

    Stock, Karl; Wurm, Holger; Hausladen, Florian

    2016-02-01

    Flashlamp pumped Er:YAG lasers are successfully used clinically for both precise soft and hard tissue ablation. Since several years a novel diode pumped Er:YAG laser system (Pantec Engineering AG) is available, with mean laser power up to 40 W and pulse repetition rate up to 1 kHz. The aim of the study was to investigate the suitability of the laser system specifically for stapedotomy. Firstly an experimental setup was realized with a beam focusing unit and a computer controlled translation stage to move the samples (slices of porcine bone) with a defined velocity while irradiation with various laser parameters. A microphone was positioned in a defined distance to the ablation point and the resulting acoustic signal of the ablation process was recorded. For comparison, measurements were also performed with a flash lamp pumped Er:YAG laser system. After irradiation the resulting ablation quality and efficacy were determined using light microscopy. Using a high speed camera and "Töpler-Schlierentechnik" the cavitation bubble in water after perforation of a bone slice was investigated. The results show efficient bone ablation using the diode pumped Er:YAG laser system. Also a decrease of the sound level and of the cavitation bubble volume was observed with decreasing pulse duration. Higher repetition rates lead to a slightly increase of thermal side effects but have no influence on the ablation efficiency. In conclusion, these first experiments demonstrate the high potential of the diode pumped Er:YAG laser system for use in middle ear surgery.

  10. Compact fluorescent lamp applications in luxury hotels

    SciTech Connect

    Gilleskie, R.J.

    1996-01-01

    Over the past several years, consumers, lighting designers, and energy conservationists have paid increasing attention to the special characteristics of compact fluorescent lamps (CFLs). CFLs can typically be used to replace incandescent lamps of three to four times their own wattage, and their color rendering indices (CRIs)-80 to 85-make them virtually indistinguishable from incandescents. The typical 10,0000-hour life of a CFL often makes savings in labor its most desirable feature when compared to a shorter-lived incandescent lamp.

  11. Lamp system for uniform semiconductor wafer heating

    SciTech Connect

    Zapata, Luis E.; Hackel, Lloyd

    2001-01-01

    A lamp system with a very soft high-intensity output is provided over a large area by water cooling a long-arc lamp inside a diffuse reflector of polytetrafluorethylene (PTFE) and titanium dioxide (TiO.sub.2) white pigment. The water is kept clean and pure by a one micron particulate filter and an activated charcoal/ultraviolet irradiation system that circulates and de-ionizes and biologically sterilizes the coolant water at all times, even when the long-arc lamp is off.

  12. Lasing studies of new coumarin derivatives under laser and lamp excitation

    SciTech Connect

    Aristov, A. V.; Veselova, T. V.; Kozlovskii, D. A.; Komlev, I. V.; Levin, M. B.; Reznichenko, A. V.; Tavrizova, M. A.; Cherkasov, A. S.

    1988-09-01

    The luminescence characteristics and results of a study of the comparative laser efficiency of ethanol solutions of a series of coumarin derivatives and rhodamine 6G are presented. It is shown that under laser excitation (neodymium laser third harmonic) and lamp excitation, the solutions of certain coumarins match rhodamine 6G in lasing efficiency values. A comparatively low photostability of the investigated coumarin solutions and its weak dependence on the spectral composition of the pumping radiation have been observed.

  13. 30 CFR 75.522-1 - Incandescent and fluorescent lamps.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Incandescent and fluorescent lamps. 75.522-1...-1 Incandescent and fluorescent lamps. (a) Except for areas of a coal mine inby the last open crosscut, incandescent lamps may be used to illuminate underground areas. When incandescent lamps are...

  14. 30 CFR 75.522-1 - Incandescent and fluorescent lamps.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Incandescent and fluorescent lamps. 75.522-1...-1 Incandescent and fluorescent lamps. (a) Except for areas of a coal mine inby the last open crosscut, incandescent lamps may be used to illuminate underground areas. When incandescent lamps are...

  15. 30 CFR 75.522-1 - Incandescent and fluorescent lamps.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Incandescent and fluorescent lamps. 75.522-1...-1 Incandescent and fluorescent lamps. (a) Except for areas of a coal mine inby the last open crosscut, incandescent lamps may be used to illuminate underground areas. When incandescent lamps are...

  16. 30 CFR 75.522-1 - Incandescent and fluorescent lamps.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Incandescent and fluorescent lamps. 75.522-1...-1 Incandescent and fluorescent lamps. (a) Except for areas of a coal mine inby the last open crosscut, incandescent lamps may be used to illuminate underground areas. When incandescent lamps are...

  17. 49 CFR 393.23 - Power supply for lamps.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.23 Power supply for lamps. All required lamps must be powered by the electrical system of the motor vehicle with the exception of battery powered lamps used on projecting loads....

  18. 49 CFR 393.23 - Power supply for lamps.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.23 Power supply for lamps. All required lamps must be powered by the electrical system of the motor vehicle with the exception of battery powered lamps used on projecting loads....

  19. 49 CFR 393.23 - Power supply for lamps.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.23 Power supply for lamps. All required lamps must be powered by the electrical system of the motor vehicle with the exception of battery powered lamps used on projecting loads....

  20. FLASH LIDAR Based Relative Navigation

    NASA Technical Reports Server (NTRS)

    Brazzel, Jack; Clark, Fred; Milenkovic, Zoran

    2014-01-01

    Relative navigation remains the most challenging part of spacecraft rendezvous and docking. In recent years, flash LIDARs, have been increasingly selected as the go-to sensors for proximity operations and docking. Flash LIDARS are generally lighter and require less power that scanning Lidars. Flash LIDARs do not have moving parts, and they are capable of tracking multiple targets as well as generating a 3D map of a given target. However, there are some significant drawbacks of Flash Lidars that must be resolved if their use is to be of long-term significance. Overcoming the challenges of Flash LIDARs for navigation-namely, low technology readiness level, lack of historical performance data, target identification, existence of false positives, and performance of vision processing algorithms as intermediaries between the raw sensor data and the Kalman filter-requires a world-class testing facility, such as the Lockheed Martin Space Operations Simulation Center (SOSC). Ground-based testing is a critical step for maturing the next-generation flash LIDAR-based spacecraft relative navigation. This paper will focus on the tests of an integrated relative navigation system conducted at the SOSC in January 2014. The intent of the tests was to characterize and then improve the performance of relative navigation, while addressing many of the flash LIDAR challenges mentioned above. A section on navigation performance and future recommendation completes the discussion.

  1. LED lamp power management system and method

    DOEpatents

    Gaines, James; Clauberg, Bernd; Van Erp, Josephus A. M.

    2013-03-19

    An LED lamp power management system and method including an LED lamp having an LED controller 58; a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 reduces power loss in one of the channel switch 62 and the shunt switch 68 when LED lamp electronics power loss (P.sub.loss) exceeds an LED lamp electronics power loss limit (P.sub.lim); and each of the channel switches 62 receives a channel switch control signal 63 from the LED controller 58 and each of the shunt switches 68 receives a shunt switch control signal 69 from the LED controller 58.

  2. CALiPER Retail Lamps Study 3

    SciTech Connect

    Royer, Michael P.; Beeson, Tracy A.

    2014-02-01

    The CALiPER program first began investigating LED lamps sold at retail stores in 2010, purchasing 33 products from eight retailers and covering six product categories. The findings revealed a fragmented marketplace, with large disparities in performance of different products, accuracy of manufacturer claims, and offerings from different retail outlets. Although there were some good products, looking back many would not be considered viable competitors to other available options, with too little lumen output, not high enough efficacy, or poor color quality. CALiPER took another look in late 2011purchasing 38 products of five different types from nine retailers and the improvement was marked. Performance was up; retailer claims were more accurate; and the price per lumen and price per unit efficacy were down, although the price per product had not changed much. Nonetheless, there was still plenty of room for improvement, with the performance of LED lamps not yet reaching that of well-established classes of conventional lamps (e.g., 75 W incandescent A19 lamps). Since the second retail lamp study was published in early 2012, there has been substantial progress in all aspects of LED lamps available from retailers. To document this progress, CALiPER again purchased a sample of lamps from retail stores 46 products in total, focusing on A19, PAR30, and MR16 lamps but instead of a random sample, sought to select products to answer specific hypotheses about performance. These hypotheses focused on expanding ranges of LED equivalency, the accuracy of lifetime claims, efficacy and price trends, as well as changes to product designs. Among other results, key findings include: There are now very good LED options to compete with 60 W, 75 W, and 100 W incandescent A19 lamps, and 75 W halogen PAR30 lamps. MR16 lamps have shown less progress, but there are now acceptable alternatives to 35 W, 12 V halogen MR16 lamps and 50 W, 120 V halogen MR16 lamps for some applications. Other

  3. UVIS tungsten lamp cross-check

    NASA Astrophysics Data System (ADS)

    Baggett, Sylvia

    2009-07-01

    This proposal will verify the operation of the spare UVIS channel calsystem tungsten lamp. Internal flatfields will be obtained in one filter from each of the twelve filter wheels, providing an initial baseline and comparison for those taken with the primary lamp {WF09, 11422}. Filters for this proposal were chosen based upon a balance of multiple factors: reasonable countrate with calsystem tungsten lamp {no long exposure times}, science priority of the filter, overall coverage of UVIS wavelength regime, and slot location in the wheel. Exposures will be taken in the default full-frame, four-amp, unbinned readout mode.This proposal corresponds to the spare lamp portion of SMOV activity id WFC3-09.

  4. WFC3 SS UVIS Spare Tungsten Lamp

    NASA Astrophysics Data System (ADS)

    MacKenty, John

    2012-10-01

    Part of side switch activities.This proposal will verify the operation of the spare UVIS channel calsystem tungsten lamp. Internal flatfields will be obtained in one filter from each of the twelve filter wheels, providing an initial baseline and comparison for those taken with the primary lamp {WF09}. Filters for this proposal were chosen based upon a balance of multiple factors: reasonable countrate with calsystem tungsten lamp {no long exposure times}, science priority of the filter, overall coverage of UVIS wavelength regime, and slot location in the wheel. Exposures will be taken in the default full-frame, four-amp, unbinned readout mode.This proposal corresponds to the spare lamp portion of SS SMOV activity ID: WF09b

  5. Spectral comparisons of sunlight and different lamps

    NASA Technical Reports Server (NTRS)

    Deitzer, Gerald

    1994-01-01

    The tables in this report were compiled to characterize the spectra of available lamp types and provide comparison to the spectra of sunlight. Table 1 reports the spectral distributions for various lamp sources and compares them to those measured for sunlight. Table 2 provides the amount of energy in Wm(exp -2) relative to the number of photons of PAR (photosynthetically active radiation) (400-700 nm) for each light source.

  6. Electrodeless-discharge-vapor-lamp-based Faraday anomalous-dispersion optical filter.

    PubMed

    Sun, Qinqing; Zhuang, Wei; Liu, Zhiwen; Chen, Jingbiao

    2011-12-01

    We report an excited-state Faraday anomalous-dispersion optical filter operating on the rubidium 5P(3/2)-5D(5/2) transition (775.9 nm in vacuum) without the use of a pump laser. An electrodeless discharge vapor lamp is employed to replace the Rb vapor cell in a traditional Faraday anomalous-dispersion optical filter system. Atoms can be excited by power rather than a complex frequency-locked pump laser. A proof-of-concept experimental demonstration with a maximum transmission of 1.9% and a filter bandwidth of 650 MHz is presented. PMID:22139259

  7. High frequency inductive lamp and power oscillator

    DOEpatents

    MacLennan, Donald A.; Turner, Brian P.; Dolan, James T.; Kirkpatrick, Douglas A.; Leng, Yongzhang

    2000-01-01

    A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and/or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to match the driving frequency of the oscillator to a plurality of tuning states of the lamp.

  8. PUMP CONSTRUCTION

    DOEpatents

    Strickland, G.; Horn, F.L.; White, H.T.

    1960-09-27

    A pump which utilizes the fluid being pumped through it as its lubricating fluid is described. This is achieved by means of an improved bearing construction in a pump of the enclosed or canned rotor type. At the outlet end of the pump, adjacent to an impeller mechanism, there is a bypass which conveys some of the pumped fluid to a chamber at the inlet end of the pump. After this chamber becomes full, the pumped fluid passes through fixed orifices in the top of the chamber and exerts a thrust on the inlet end of the pump rotor. Lubrication of the rotor shaft is accomplished by passing the pumped fluid through a bypass at the outlet end of the rotor shaft. This bypass conveys Pumped fluid to a cooling means and then to grooves on the surface of the rotor shait, thus lubricating the shaft.

  9. Industrial Pumps

    NASA Technical Reports Server (NTRS)

    1986-01-01

    A flow inducer is a device that increases the pump intake capacity of a Worthington Centrifugal pump. It lifts the suction pressure sufficiently for the rotating main impeller of the centrifugal pump to operate efficiently at higher fluid intake levels. The concept derives from 1960's NASA technology which was advanced by Worthington Pump Division. The pumps are used to recirculate wood molasses, a highly viscous substance.

  10. Corrosion testing in flash tanks

    SciTech Connect

    Clarke, S.J.; Stead, N.J.

    1999-07-01

    As kraft pulp mills adopt modified cooking processes, an increasing amount of corrosion of carbon steel digester systems is being encountered. Many mills have had severe corrosion in the flash tanks, in particular, the first ({number{underscore}sign}1) flash tank. The work described in this report was aimed at characterizing the corrosion. Coupons of carbon steel, several stainless steels and titanium were exposed at two mills. At mill A, identical sets of coupons were exposed in the {number{underscore}sign}1 and {number{underscore}sign}2 flash tank. At mill B, three identical sets of coupons were placed in flash tank {number{underscore}sign}1. The results of the exposures showed that both carbon steel and titanium suffered high rates of general corrosion, while the stainless steels suffered varying degrees of localized attack. The ranking of the resistance of corrosion in the flash tank was the same ranking as would be expected in a reducing acid environment. In the light of the coupon results, organic acids is concluded to be the most likely cause of corrosion of the flash tanks.

  11. 49 CFR 393.25 - Requirements for lamps other than head lamps.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... have each lamp located so that it meets the visibility requirements specified in the SAE standards..., and all lamps on converter dollies and pole trailers must meet the following applicable SAE standards... SAE J845—Optical Warning Devices for Authorized Emergency, Maintenance and Service Vehicles, May...

  12. 10 CFR 429.40 - Candelabra base incandescent lamps and intermediate base incandescent lamps.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Candelabra base incandescent lamps and intermediate base incandescent lamps. 429.40 Section 429.40 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification §...

  13. 10 CFR 429.40 - Candelabra base incandescent lamps and intermediate base incandescent lamps.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Candelabra base incandescent lamps and intermediate base incandescent lamps. 429.40 Section 429.40 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification §...

  14. 10 CFR 429.40 - Candelabra base incandescent lamps and intermediate base incandescent lamps.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Candelabra base incandescent lamps and intermediate base incandescent lamps. 429.40 Section 429.40 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification §...

  15. Dual-energy flash x-ray generator

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Sagae, Michiaki; Takahashi, Kei; Shikoda, Arimitsu; Oizumi, Teiji; Ojima, Hidenori; Takayama, Kazuyoshi; Tamakawa, Yoshiharu; Yanagisawa, Toru; Fujiwara, Akihiro; Mitoya, Kanji

    1995-05-01

    The fundamental studies on a dual-energy flash x-ray generator for performing the energy-selective two-direction radiography are described. This generator consisted of the following components: a negative high- voltage power supply, a polarity-inversion-type high-voltage pulser having a 5 nF combined ceramic condenser, a turbo molecular pump, and two flash x-ray tubes. The condenser in the pulser was charged from -60 to -80 kV, and the electric charges in the condenser were discharged to two x-ray tubes. The maximum output voltage from the pulser was about -1.5 times the charged voltage because the cable transmission line was employed. Using a tube, the maximum tube voltage was about 110 kV. The maximum tube current and the x-ray intensity were less than 3 kA and 5 (mu) C/kg at 0.5 m per pulse, respectively. In contrast, the tube current and the intensity has approximately half the above values when two tubes were employed. The pulse widths were less than 200 ns, and two shots of flash x rays were obtained simultaneously. Each photon energy of flash x rays can be changed by controlling the space between the anode and cathode electrodes.

  16. Protons Trigger Mitochondrial Flashes.

    PubMed

    Wang, Xianhua; Zhang, Xing; Huang, Zhanglong; Wu, Di; Liu, Beibei; Zhang, Rufeng; Yin, Rongkang; Hou, Tingting; Jian, Chongshu; Xu, Jiejia; Zhao, Yan; Wang, Yanru; Gao, Feng; Cheng, Heping

    2016-07-26

    Emerging evidence indicates that mitochondrial flashes (mitoflashes) are highly conserved elemental mitochondrial signaling events. However, which signal controls their ignition and how they are integrated with other mitochondrial signals and functions remain elusive. In this study, we aimed to further delineate the signal components of the mitoflash and determine the mitoflash trigger mechanism. Using multiple biosensors and chemical probes as well as label-free autofluorescence, we found that the mitoflash reflects chemical and electrical excitation at the single-organelle level, comprising bursting superoxide production, oxidative redox shift, and matrix alkalinization as well as transient membrane depolarization. Both electroneutral H(+)/K(+) or H(+)/Na(+) antiport and matrix proton uncaging elicited immediate and robust mitoflash responses over a broad dynamic range in cardiomyocytes and HeLa cells. However, charge-uncompensated proton transport, which depolarizes mitochondria, caused the opposite effect, and steady matrix acidification mildly inhibited mitoflashes. Based on a numerical simulation, we estimated a mean proton lifetime of 1.42 ns and diffusion distance of 2.06 nm in the matrix. We conclude that nanodomain protons act as a novel, to our knowledge, trigger of mitoflashes in energized mitochondria. This finding suggests that mitoflash genesis is functionally and mechanistically integrated with mitochondrial energy metabolism. PMID:27463140

  17. COS/FUV Mapping of Stray PtNe Lamp Light Through FCA

    NASA Astrophysics Data System (ADS)

    Oliveira, Cristina

    2010-09-01

    order.LAMP2 with CURRENT=LOW is used in all of these visits. In addition, at each position, one exposure with LAMP1 CURRENT=MED is also taken with the G130M/1055 setting, which leads to total counts in 10 sec more than a factor of 10 below the 600,000 limit. This exposure is used so that the ratio of LAMP1/MED to LAMP2/LOW can be calculated for the FCA at each position {in conjunction with the data obtained in visits 11, 12, and 13; see below}. In addition, the G130M/1055 exposures with LAMP1/MED and LAMP2/LOW will be used to determine if the lamp spot size is changing at each position.Depending on the total counts estimated for each setting, either a typical wave exposure is taken or special flash commands are used. Details are given in each visit.Exposures obtained with LAMP1/CURRENT=LOW are expected to have a 20% smaller count rate than exposures obtained with LAMP1/CURRENT=MED. Exposures obtained with LAMP2/CURRENT=MED are expected to have count rates similar to those obtained with LAMP1/CURRENT=MED, and exposures obtained with LAMP2/CURRENT=LOW are expected to have a count rate which is 1/7 of that obtainedwith LAMP2/CURRENT=MED.VISIT 10 OBTAINS LAMP1/CURRENT=MED+ LOW SPECTRA AT ALL THE M SETTINGS USED IN THIS PROGRAM, AT THE NOMINAL POSITION {0.0"}.VISIT 11 OBTAINS LAMP2/CURRENT=MED SPECTRA AT ALL THE M SETTINGS USED IN THIS PROGRAM, AT THE NOMINAL POSITION {0.0"}.VISIT 12 OBTAINS LAMP2/CURRENT=LOW SPECTRA AT ALL THE M SETTINGS USED IN THIS PROGRAM, AT THE NOMINAL POSITION {0.0"}.VISIT 13 OBTAINS LAMP1/CURRENT=MED, LOW AND LAMP2/CURRENT=MED, LOW SPECTRA AT ALL OF THE L SETTINGS USED IN THIS PROGRAM, AT THE NOMINAL POSITION {0.0"}.THE GOAL OF THESE VISITS IS TO DETERMINE THE RATIOS OF THE DIFFERENT LAMP SETTINGS AT DIFFERENT WAVELENGTHS, TO HELP IN ANALYZING THE DATA OBTAINED IN VISITS WHERE ONLY LAMP2/LOW IS USED.ALSO, THESE DATA WILL BE USED TO PREDICT WHAT THE COUNTS WOULD BE WITH G140L/1280/LAMP1/MED AT THE +6.0" POSITION {VIS6N, WHERE LAMP2/LOW IS USED}. THESE

  18. LED solution for E14 candle lamp

    NASA Astrophysics Data System (ADS)

    Li, Yun; Liu, Ye; Boonekamp, Erik P.; Shi, Lei; Mei, Yi; Jiang, Tan; Guo, Qing; Wu, Huarong

    2009-08-01

    On a short to medium term, energy efficient retrofit LED products can offer an attractive solution for traditional lamps replacement in existing fixtures. To comply with user expectations, LED retrofit lamps should not only have the same mechanical interface to fit (socket and shape), but also have the similar light effect as the lamps they replace. The decorative lighting segment shows the best conditions to meet these requirements on short term. In 2008, Philips Lighting Shanghai started with the development of an LED candle lamp for the replacement of a 15W Candle shape (B35 E14) incandescent bulb, which is used in e.g. chandeliers. In this decorative application the main objective is not to generate as much light as possible, but the application requires the lamp to have a comparable look and, primarily, the same light effect as the incandescent candle lamp. This effect can be described as sparkling light, and it has to be directed sufficiently downwards (i.e., in the direction of the base of the lamp). These requirements leave very limited room for optics, electronics, mechanics and thermal design to play with in the small outline of this lamp. The main voltage AC LED concept is chosen to save the space for driver electronics. However the size of the AC LED is relatively big, which makes the optical design challenging. Several optical solutions to achieve the required light effect, to improve the optical efficiency, and to simplify the system are discussed. A novel prismatic lens has been developed which is capable of transforming the Lambertian light emission from typical high power LEDs into a butter-fly intensity distribution with the desired sparkling light effect. Thanks to this lens no reflecting chamber is needed, which improves the optical efficiency up to 70%, while maintaining the compact feature of the original optics. Together with advanced driver solution and thermal solution, the resulting LED candle lamp operates at 230V, consumes 1.8W, and

  19. Max Tech and Beyond: Fluorescent Lamps

    SciTech Connect

    Scholand, Michael

    2012-04-01

    Fluorescent lamps are the most widely used artificial light source today, responsible for approximately 70% of the lumens delivered to our living spaces globally. The technology was originally commercialized in the 1930's, and manufacturers have been steadily improving the efficacy of these lamps over the years through modifications to the phosphors, cathodes, fill-gas, operating frequency, tube diameter and other design attributes. The most efficient commercially available fluorescent lamp is the 25 Watt T5 lamp. This lamp operates at 114-116 lumens per watt while also providing good color rendering and more than 20,000 hours of operating life. Industry experts interviewed indicated that while this lamp is the most efficient in the market today, there is still a further 10 to 14% of potential improvements that may be introduced to the market over the next 2 to 5 years. These improvements include further developments in phosphors, fill-gas, cathode coatings and ultraviolet (UV) reflective glass coatings. The commercialization of these technology improvements will combine to bring about efficacy improvements that will push the technology up to a maximum 125 to 130 lumens per watt. One critical issue raised by researchers that may present a barrier to the realization of these improvements is the fact that technology investment in fluorescent lamps is being reduced in order to prioritize research into light emitting diodes (LEDs) and ceramic metal halide high intensity discharge (HID) lamps. Thus, it is uncertain whether these potential efficacy improvements will be developed, patented and commercialized. The emphasis for premium efficacy will continue to focus on T5 lamps, which are expected to continue to be marketed along with the T8 lamp. Industry experts highlighted the fact that an advantage of the T5 lamp is the fact that it is 40% smaller and yet provides an equivalent lumen output to that of a T8 or T12 lamp. Due to its smaller form factor, the T5 lamp

  20. Online inspection of circular fluorescent lamp

    NASA Astrophysics Data System (ADS)

    Ang, Beng-Hoe

    1998-10-01

    One step in the manufacture of circular fluorescent lamps is the mercury (Hg) injection process in which a small amount of mercury approximately 20 mg is injected into the fluorescent tube. An on-line detection of mercury is required to ensure that the amount of mercury residual inside the tube is within the acceptable tolerance. This critical operation is to reduce manufacturing overhead by controlling cost and reducing waste of materials. In view of this, an attempt has been made to design and develop an on- line mercury detection system with important benefits to the manufacturers, such as increased throughput, accuracy, reliability and consistency. This paper presents the configuration and development works of the on-line circular fluorescent lamp inspection system developed by Industrial Project Group--Machine Vision Center of Nanyang Polytechnic. The inspection system performs on-line detection of mercury particles (Hg) inside the circular fluorescent lamp. Taking the orientation and translation offsets of the lamp into consideration, it detects the presence/absence as well as the size of the injected mercury. The system has been successfully operating 15 hours per day and inspecting more than 22 thousands lamps in the production plant.

  1. High frequency inductive lamp and power oscillator

    DOEpatents

    MacLennan, Donald A.; Dymond, Jr., Lauren E.; Gitsevich, Aleksandr; Grimm, William G.; Kipling, Kent; Kirkpatrick, Douglas A.; Ola, Samuel A.; Simpson, James E.; Trimble, William C.; Tsai, Peter; Turner, Brian P.

    2001-01-01

    A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and I or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to adjust the driving frequency of the oscillator.

  2. Menopausal hot flashes: Randomness or rhythmicity

    NASA Astrophysics Data System (ADS)

    Kronenberg, Fredi

    1991-10-01

    Menopausal hot flashes are episodes of flushing, increased heart rate, skin blood flow and skin temperature, and a sensation of heat. The thermoregulatory and cardiovascular concomitants of hot flashes are associated with peaks in the levels of various hormones and neurotransmitters in the peripheral circulation. Although hot flashes affect about 75% of women, and are the primary reason that women at menopause seek medical attention, the mechanism of hot flashes is still not understood. Hot flashes vary in frequency and intensity both within and between individuals, and have been thought of as occurring randomly. Yet, some women report that their hot flashes are worse at a particular time of day or year. Initial examination of subjects' recordings of their hot flashes showed diurnal patterns of hot flash occurrence. There also seems to be a diurnal rhythm of hot flash intensity. Continuous physiological monitoring of hot flashes is facilitating the analysis of these patterns, which is revealing circadian and ultradian periodicities. The occurrence of hot flashes can be modulated by external and internal factors, including ambient temperature and fever. Rhythms of thermoregulatory and endocrine functions also may influence hot flash patterns. Examination of the interrelationships between the various systems of the body involved in hot flashes, and a multidisciplinary approach to the analysis of hot flash patterns, will aid our understanding of this complex phenomenon.

  3. Electronic Flash In Data Acquisition

    NASA Astrophysics Data System (ADS)

    Miller, C. E.

    1982-02-01

    Photographic acquisition of data often may be simplified, or the data quality improved upon by employing electronic flash sources with traditional equipment or techniques. The relatively short flash duration compared to movie camera shutters, or to the long integration time of video camera provides improved spatial resolution through blur reduction, particularly important as image movement becomes a significant fraction of film format dimension. Greater accuracy typically is achieved in velocity and acceleration determinations by using a stroboscopic light source rather than a movie camera frame-rate control as a time standard. Electrical efficiency often is an important advantage of electronic flash sources since almost any necessary light level for exposure may be produced, yet the source typically is "off" most of the time. Various synchronization techniques greatly expand the precise control of exposure. Biomechanical and sports equipment studies may involve velocities up to 200 feet-per-second, and often will have associated very rapid actions of interest. The need for brief exposures increases H.s one "ZOOMS in on the action." In golf, for example, the swing may be examined using 100 microsecond (Us) flashes at rates of 60 or 120 flashes-per-second (FPS). Accurate determination of linear and rotational velocity of the ball requires 10 Us flashes at 500-1,000 FPS, while sub-Us flashes at 20,000-50,000 FPS are required to resolve the interaction of the ball and the club, head. Some seldom. used techniques involving streak photography are described, with enhanced results obtained by combining strobe with the usual continuous light source. The combination of strobe and a fast electro-mechanical shutter is considered for Us photography under daylight conditions.

  4. Retail Lamps Study 3.1: Dimming, Flicker, and Power Quality Characteristics of LED A Lamps.

    SciTech Connect

    Royer, Michael P.; Poplawski, Michael E.; Brown, Charles C.

    2014-12-14

    To date, all three reports in the retail lamps series have focused on basic performance parameters, such as lumen output, efficacy, and color quality. This report goes a step further, examining the photoelectric characteristics (i.e., dimming and flicker) of a subset of lamps from CALiPER Retails Lamps Study 3. Specifically, this report focuses on the dimming, power quality, and flicker characteristics of 14 LED A lamps, as controlled by four different retail-available dimmers. The results demonstrate notable variation across the various lamps, but little variation between the four dimmers. Overall, the LED lamps: ~tended to have higher relative light output compared to the incandescent and halogen benchmark at the same dimmer output signal (RMS voltage). The lamps’ dimming curves (i.e., the relationship between control signal and relative light output) ranged from linear to very similar to the square-law curve typical of an incandescent lamp. ~generally exhibited symmetrical behavior—the same dimming curve—when measured proceeding from maximum to minimum or minimum to maximum control signal. ~mostly dimmed below 10% of full light output, with some exceptions for specific lamp and dimmer combinations ~exhibited a range of flicker characteristics, with many comparing favorably to the level typical of a magnetically-ballasted fluorescent lamp through at least a majority of the dimming range. ~ always exceeded the relative (normalized) efficacy over the dimming range of the benchmark lamps, which rapidly decline in efficacy when they are dimmed. This report generally does not attempt to rank the performance of one product compared to another, but instead focuses on the collective performance of the group versus conventional incandescent or halogen lamps, the performance of which is likely to be the baseline for a majority of consumers. Undoubtedly, some LED lamps perform better—or more similar to conventional lamps—than others. Some perform desirably for one

  5. Experimental study of high-speed photonic imaging using a flash-lamp system

    NASA Astrophysics Data System (ADS)

    Hamada, Yutaka

    1997-05-01

    A flashlight system has been developed to generate high intensity luminance which would allow high speed imaging up to 10,000 frames per second in the field where there was no power supply or in a room with restricted power capacity. It gives higher luminance than continuous light sources thus making it possible to set shorter exposure times and use a smaller aperture lens at the same framing rate. We have obtained many successful color images by using a combination of this light source and a 16 mm rotating prism camera. This paper outlines the features of the flashlight system, and describes some applications that make best use of this system.

  6. Optical pumping in a microfabricated Rb vapor cell using a microfabricated Rb discharge light source

    SciTech Connect

    Venkatraman, V.; Kang, S.; Affolderbach, C.; Mileti, G.; Shea, H.

    2014-02-03

    Miniature (pumping of alkali atoms, such as atomic clocks and magnetometers, today mostly employ vertical-cavity surface-emitting lasers as pump light sources. Here, we report on the demonstration of optical pumping in a microfabricated alkali vapor resonance cell using (1) a microfabricated Rb discharge lamp light source, as well as (2) a conventional glass-blown Rb discharge lamp. The microfabricated Rb lamp cell is a dielectric barrier discharge (DBD) light source, having the same inner cell volume of around 40 mm{sup 3} as that of the resonance cell, both filled with suitable buffer gases. A miniature (∼2 cm{sup 3} volume) test setup based on the M{sub z} magnetometer interrogation technique was used for observation of optical-radiofrequency double-resonance signals, proving the suitability of the microfabricated discharge lamp to introduce efficient optical pumping. The pumping ability of this light source was found to be comparable to or even better than that of a conventional glass-blown lamp. The reported results indicate that the micro-fabricated DBD discharge lamp has a high potential for the development of a new class of miniature atomic clocks, magnetometers, and quantum sensors.

  7. Optical radiation emissions from compact fluorescent lamps.

    PubMed

    Khazova, M; O'Hagan, J B

    2008-01-01

    There is a drive to energy efficiency to mitigate climate change. To meet this challenge, the UK Government has proposed phasing out incandescent lamps by the end of 2011 and replacing them with energy efficient fluorescent lighting, including compact fluorescent lamps (CFLs) with integrated ballasts. This paper presents a summary of an assessment conducted by the Health Protection Agency in March 2008 to evaluate the optical radiation emissions of CFLs currently available in the UK consumer market. The study concluded that the UV emissions from a significant percentage of the tested CFLs with single envelopes may result in foreseeable overexposure of the skin when these lamps are used in desk or task lighting applications. The optical output of all tested CFLs, in addition to high-frequency modulation, had a 100-Hz envelope with modulation in excess of 15%. This degree of modulation may be linked to a number of adverse effects. PMID:18757896

  8. LAMP proteins are required for fusion of lysosomes with phagosomes.

    PubMed

    Huynh, Kassidy K; Eskelinen, Eeva-Liisa; Scott, Cameron C; Malevanets, Anatoly; Saftig, Paul; Grinstein, Sergio

    2007-01-24

    Lysosome-associated membrane proteins 1 and 2 (LAMP-1 and LAMP-2) are delivered to phagosomes during the maturation process. We used cells from LAMP-deficient mice to analyze the role of these proteins in phagosome maturation. Macrophages from LAMP-1- or LAMP-2-deficient mice displayed normal fusion of lysosomes with phagosomes. Because ablation of both the lamp-1 and lamp-2 genes yields an embryonic-lethal phenotype, we were unable to study macrophages from double knockouts. Instead, we reconstituted phagocytosis in murine embryonic fibroblasts (MEFs) by transfection of FcgammaIIA receptors. Phagosomes formed by FcgammaIIA-transfected MEFs obtained from LAMP-1- or LAMP-2- deficient mice acquired lysosomal markers. Remarkably, although FcgammaIIA-transfected MEFs from double-deficient mice ingested particles normally, phagosomal maturation was arrested. LAMP-1 and LAMP-2 double-deficient phagosomes acquired Rab5 and accumulated phosphatidylinositol 3-phosphate, but failed to recruit Rab7 and did not fuse with lysosomes. We attribute the deficiency to impaired organellar motility along microtubules. Time-lapse cinematography revealed that late endosomes/lysosomes as well as phagosomes lacking LAMP-1 and LAMP-2 had reduced ability to move toward the microtubule-organizing center, likely precluding their interaction with each other. PMID:17245426

  9. Fundamental studies on a heat driven lamp

    NASA Technical Reports Server (NTRS)

    Lawless, J. L.

    1985-01-01

    A detailed theoretical study of a heat-driven lamp has been performed. This lamp uses a plasma produced in a thermionic diode. The light is produced by the resonance transition of cesium. An important result of this study is that up to 30% of the input heat is predicted to be converted to light in this device. This is a major improvement over ordinary thermionic energy converters in which only approx. 1% is converted to resonance radiation. Efficiencies and optimum inter-electrode spacings have been found as a function of cathode temperature and the radiative escape factor. The theory developed explains the operating limits of the device.

  10. Blackbody Radiation from an Incandescent Lamp

    NASA Astrophysics Data System (ADS)

    Ribeiro, C. I.

    2014-09-01

    In this article we propose an activity aimed at introductory students to help them understand the Stefan-Boltzmann and Wien's displacement laws. It only requires simple materials that are available at any school: an incandescent lamp, a variable dc energy supply, and a computer to run an interactive simulation of the blackbody spectrum. Essentially, the activity consists of calculating the filament's temperature for different values of electric power and comparing the color and brightness of the lamp's light, as seen by the eye, with the correspondent (simulated) black-body spectrum. Although the comparison is only qualitative, we find that the activity provides a tangible introduction to blackbody radiation.