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Sample records for 308-nm excimer lamp

  1. Pathogen control in complex fluids with water-coupled excimer lamps at 282 and 308 nm.

    PubMed

    Coogan, John J

    2005-01-01

    Water-coupled excimer lamp systems have been developed to inactivate microorganisms within complex, low-optical quality, fluids. Monochromatic lamps were selected to minimize UV-B and UV-C absorption within the carrier fluids while maximizing deposition within specific chemical targets. Fundamentals, system scaling and power supply design are discussed. This work used two large-surface area excimer lamps as intense sources of near monochromatic radiation at 308 and 282 nm. Data are presented for two distinct fluid systems: flow-through processing of large-volume metalworking fluids used in heavy industry and batch irradiation of human blood plasma and platelet suspensions used in transfusion medicine. In the first, a 200-600 L/min reactor is used to control bacterial concentrations within metalworking fluids used in large-scale metal machining processes. Control is defined as the maintenance of 10(3) to 10(4) CFU/mL in fluids that without treatment would have concentrations over 10(7) CFU/mL. The second is a batch process for viral inactivation in undiluted blood bank products. Samples of fresh frozen plasma and platelet suspensions were spiked with high titers of porcine parvovirus (PPV) and irradiated at 308 and 282 nm. Although both wavelengths were effective at reducing PPV levels, 308 nm light resulted in both higher rates of viral inactivation (greater than 6 log units) and lower rates of fluid degradation.

  2. 308-nm excimer laser in endodontics

    NASA Astrophysics Data System (ADS)

    Liesenhoff, Tim

    1992-06-01

    Root canal preparation was performed on 20 extracted human teeth. After opening the coronal pulp, the root canals were prepared by 308 nm excimer laser only. All root canals were investigated under SEM after separation in the axial direction. By sagittal separation of the mandibles of freshly slaughtered cows, it was possible to get access to the tissues and irradiate under optical control. Under irradiation of excimer laser light, tissue starts to fluoresce. It was possible to demonstrate that each tissue (dentin, enamel, bone, pulpal, and connective tissue) has a characteristic spectral pattern. The SEM analyses showed that it is well possible to prepare root canals safely. All organic soft tissue has been removed by excimer laser irradiation. There was no case of via falsa. The simultaneous spectroscopic identification of the irradiated tissue provides a safe protection from overinstrumentation. First clinical trials on 20 patients suffering of chronical apical parodontitis have been carried out successfully.

  3. Applications of the 308-nm excimer laser in dermatology

    NASA Astrophysics Data System (ADS)

    Farkas, A.; Kemeny, L.

    2006-05-01

    Excimer lasers contain a mixture of a noble inert gas and a halogen, which form excited dimers only in the activated state. High-energy current is used to produce these dimers, which have a very short lifetime, and after their fast dissociation they release the excitation energy through ultraviolet photons. The application of these lasers proved to be successful in medicine, including the field of ophthalmology, cardiology, angiology, dentistry, orthopaedics, and, in recent years, dermatology. For medical purposes, the 193-nm argon fluoride, the 248-nm krypton fluoride, the 351-nm xenon fluoride, and the 308-nm xenon chloride lasers are used. Recently, the 308-nm xenon chloride laser has gained much attention as a very effective treatment modality in dermatological disorders. It was successfully utilized in psoriasis; later, it proved to be useful in handling other lightsensitive skin disorders and even in the treatment of allergic rhinitis. This review summarizes the possible applications of this promising tool in dermatology.

  4. Electrical and chemical properties of XeCl*(308 nm) exciplex lamp created by a dielectric barrier discharge

    SciTech Connect

    Baadj, S.; Harrache, Z. Belasri, A.

    2013-12-15

    The aim of this work is to highlight, through numerical modeling, the chemical and the electrical characteristics of xenon chloride mixture in XeCl* (308 nm) excimer lamp created by a dielectric barrier discharge. A temporal model, based on the Xe/Cl{sub 2} mixture chemistry, the circuit and the Boltzmann equations, is constructed. The effects of operating voltage, Cl{sub 2} percentage in the Xe/Cl{sub 2} gas mixture, dielectric capacitance, as well as gas pressure on the 308-nm photon generation, under typical experimental operating conditions, have been investigated and discussed. The importance of charged and excited species, including the major electronic and ionic processes, is also demonstrated. The present calculations show clearly that the model predicts the optimal operating conditions and describes the electrical and chemical properties of the XeCl* exciplex lamp.

  5. Ablation of bone and polymethylmethacrylate by an XeCl (308 nm) excimer laser

    SciTech Connect

    Yow, L.; Nelson, J.S.; Berns, M.W.

    1989-01-01

    One of the main problems in orthopaedics is the surgical removal of hard substances, such as bone and polymethylmethacrylate (PMMA). Such materials are often very difficult to remove without mechanical trauma to the remaining tissue. This study investigated the feasibility of the ultraviolet 308 nm excimer laser in the ablation of these materials. The beam was delivered through a 1 mm-diameter fiber optic at 40 Hz with energy densities at the target surface of 20-80 J/cm2 per pulse. The goal of the study was to establish the ideal dosimetry for removing bone and PMMA with minimum trauma to the adjacent tissue. Histology revealed that the 308 nm laser effectively removed bone leaving a thermal damage zone of only 2-3 microns in the remaining tissue. Increasing the energy per pulse gave correspondingly larger and deeper cuts with increasing zones of thermal damage. The excimer laser was also effective in the ablation of PMMA, creating craters in the substrate with a thermal damage zone of 10-40 microns. The debris from both substrates was evaluated.

  6. Interaction of 308-nm excimer laser light with temporomandibular joint related structures

    NASA Astrophysics Data System (ADS)

    Liesenhoff, Tim; Funk, Armin

    1994-02-01

    Arthroscopy of TMJ has become a clinically important and more and more accepted method for diagnosis and treatment of TMJ alteration. This minimal invasive method is clearly limited by the anatomical dimensions of the TMJ. A 308 nm excimer laserlight has already found clinical applications in angioplasty, ophthalmology, and dentistry. The aim of the presented study was to find out if it is possible to ablate TMJ related structures under arthroscopic conditions. It also aims to evaluate the energy-threshold for ablation and the maximal possible rate of ablation. Contrary to other laser systems it offers a unique combination of minimal tissue alteration, precise tissue ablation guidability through optical fibers, and a good transmission through water.

  7. Absorption of 308-nm excimer laser radiation by balanced salt solution, sodium hyaluronate, and human cadaver eyes

    SciTech Connect

    Keates, R.H.; Bloom, R.T.; Schneider, R.T.; Ren, Q.; Sohl, J.; Viscardi, J.J. )

    1990-11-01

    Absorption of the excimer laser radiations of 193-nm argon fluorine and 308-nm xenon chloride in balanced salt solution, sodium hyaluronate, and human cadaver eyes was measured. The absorption of these materials as considerably different for the two wavelengths; we found that 308-nm light experienced much less absorption than the 193-nm light. The extinction coefficient (k) for 308 nm was k = 0.19/cm for balanced salt solution and k = 0.22/cm for sodium hyaluronate. In contrast to this, the extinction coefficient for 193 nm was k = 140/cm for balanced salt solution and k = 540/cm for sodium hyaluronate. Two 1-day-old human phakic cadaver eyes showed complete absorption with both wavelengths. Using aphakic eyes, incomplete absorption was noted at the posterior pole with 308 nm and complete absorption was noted with 193 nm. The extinction in the anterior part of aphakic eyes (the first 6 mm) was 4.2/cm for 308 nm, meaning that the intensity of the light is reduced by a factor of 10 after traveling the first 5.5 mm. However, we observed that the material in the eye fluoresces, meaning the 308 nm is transformed into other (longer) wavelengths that travel through the total eye with minimal absorption. Conclusions drawn from this experiment are that the use of the 308-nm wavelength may have undesirable side effects, while the use of the 193-nm wavelength should be consistent with ophthalmic use on both the cornea and the lens.

  8. Successful treatment with 308-nm monochromatic excimer light and subsequent tacrolimus 0.03% ointment in refractory plasma cell cheilitis.

    PubMed

    Yoshimura, Kazuhiro; Nakano, Shunji; Tsuruta, Daisuke; Ohata, Chika; Hashimoto, Takashi

    2013-06-01

    Plasma cell cheilitis is a chronic inflammatory disease that presents with erythema, erosions, ulcers and occasional nodules within the mucosa, including the lips. It is histopathologically characterized by dense plasma cell infiltration in the lamina propria of the mucous membranes. Several treatments for plasma cell cheilitis have been reported, including topical steroids, topical antibiotics or topical tacrolimus. However, 308-nm monochromatic excimer light (MEL) has never been reported as a treatment option, while it was reported to be very effective in treating erosive oral lichen planus. We report a 62-year-old man who had chronic plasma cell cheilitis on the lower lip, which was refractory to topical and systemic corticosteroid. The lesion and severe pain were significantly improved by the treatment with nine sessions of 308-nm MEL twice per week with a total dose of 1120 mJ/cm(2). However, the lesion gradually worsened after treatment frequency was reduced to once per month. Subsequent tacrolimus 0.03% ointment cleared the lesion completely in a month and no recurrence was observed a year later. Refractory plasma cell cheilitis and concomitant severe pain quickly responded to 308-nm MEL when administrated twice per week. Because the long interval between each MEL treatment seemed ineffective to improve the lesion, appropriate frequency and adequate total dose of MEL treatment may be necessary for a successful treatment.

  9. Treatment of psoriasis and long-term maintenance using 308 nm excimer laser, clobetasol spray, and calcitriol ointment: a case series.

    PubMed

    Wong, Jillian W; Nguyen, Tien V; Bhutani, Tina; Koo, John Y M

    2012-08-01

    Psoriasis is a chronic inflammatory skin disease that is characterized by thickened red plaques covered with silvery scales. Excimer laser therapy is a cutting-edge advancement in UVB phototherapy. In contrast to traditional phototherapy, the 308 nm excimer laser only targets psoriasis plaques, while it spares uninvolved skin. It allows for treatment with a supra-erythmogenic dose of UVB irradiation. Targeted UVB therapy is a possible treatment especially for many who have failed topical treatments, systemic therapy, and traditional phototherapy. For safe and effective psoriasis treatment, a combination of therapies may be used, including a combination of laser treatment with topical medications. We present two cases demonstrating effective treatment with excimer laser in conjunction with clobetasol spray and calcitriol ointment for 12 weeks. Long-term near-clearance of psoriasis was sustained after 6 months and one-year follow up periods without further therapy.

  10. Coaxial HgI excimer lamps

    SciTech Connect

    Malinin, A N; Polyak, A V; Guivan, N N; Shimon, Lyudvik L; Zubrilin, N G

    2002-02-28

    The emission of coaxial HgI excimer lamps pumped by a repetitively pulsed barrier discharge is experimentally studied. The stable operation of the excimer lamps was demonstrated at pump-pulse repetition rates from 0.5 to 12 kHz, and the average emission power attained of 0.6 W at 444 nm. It was found that upon an addition of 0.8% of xenon to the mixture of helium and mercury diiodide, the pulse and average emission powers increased by 30%. The emission power reduced by 5% after 2.5 x 10{sup 6} pulses. An interpretation of the results of optimising the excimer lamp characteristics is given. (laser applications and other topics in quantum electronics)

  11. Absorption by XeCl* excimer molecules of their own emission of the B-X transition (λ = 308 nm) in a dense Ar-Xe-CCl4 medium upon pumping by fast electrons and uranium-235 fission fragments

    NASA Astrophysics Data System (ADS)

    Mis'kevich, A. I.; Dyuzhov, Yu. A.; Suvorov, A. A.

    2016-08-01

    Luminescence of dense Ar-Xe-CCl4 gas mixtures with a low CCl4 content upon pumping by fast electrons and uranium-235 fission fragments is studied by spectroscopic methods. It is found that, in a cell with a resonator tuned to the B-X transition of the XeCl* molecule (λ = 308 nm), the D-state population of the XeCl* excimer molecule (the D-X transition, λ = 235 nm) depends on the B-state population and increases by many times with increasing B-state population of the XeCl* molecule. The stimulated absorption coefficient k = 1.2 × 10-16 of B-X transition emission of the XeCl* molecule (λmax = 308 nm), which leads to population of the D-state of this molecule, and the coefficient of amplification μ = 2.5 × 10-4 cm-1 of B-X transition emission of the Xe Cl* molecule (λ = 308 nm) are measured upon pumping by uranium- 235 fission fragments with the specific energy input into the gas medium of ~60 mJ/cm3 and a specific power of energy input of about 240 W/cm3.

  12. Comparison of ablation channels created by the ultrapulsed CO2 laser, holmium laser, and 308-nm excimer laser in view of transmyocardial revascularization

    NASA Astrophysics Data System (ADS)

    Sachinopoulou, Anna; Verdaasdonck, Rudolf M.; Beek, Johan F.

    1996-05-01

    The perfusion of hibernating myocardium by oxygenated blood coming from transmyocardial channels to the left ventricular cavity has been considered as an alternative for patients unsuitable for bypass surgery. Channels created by lasers are believed to assure patency in the long term. At this moment, several laser systems have become available to create these channels with minimal thermal effects. The systems should be ECG triggered and the exposure should preferably be within the relaxation phase of the cardiac cycle (0.1 - 0.2 s). The lasers examined were an ultrapulsed carbon-dioxide laser with long focus delivery optics, a Holmium laser coupled to a 1 mm spot fiber and an Excimer laser coupled to a 950 fiber. Pieces of bovine myocardium (10 - 20 mm thickness) were exposed while the displacement during penetration was monitored. Pulse trains were delivered within 0.05 - 0.2 s with a repetition rate of 1 - 3 Hz. The fiber delivery devices were loaded with weights between 10 - 80 gram to study the influence of exerted force. For the carbon dioxide laser the creation of the channels was also recorded on high speed video and with a thermal imaging method in a model tissue to visualize explosive and thermal effects. With the Holmium laser immediate penetration of the fiber was obtained while with the Excimer laser the penetration of the fiber started only after several pulses within the train depending on force and energy. The carbon-dioxide laser beam created a channel instantly, up to 30 mm/pulse depending on spotsize and energy. We conclude that all three lasers are capable of creating a channel of 20 mm long on the heart within a few cardiac cycles. Histologic analysis showed that in contrast to the smooth channels of the carbon-dioxide laser, the Holmium and Excimer laser create irregular channels with ruptures to the sides with some thermal damage. It is not clear which kind of channels will have the best potentials to provide maximum perfusion of the

  13. 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.

  14. Selective irradiation of radicals for biomedical treatment using vacuum ultraviolet light from an excimer lamp

    NASA Astrophysics Data System (ADS)

    Ono, Ryo; Tokumitsu, Yusuke; Zen, Shungo; Yonemori, Seiya

    2014-10-01

    In plasma medicine, radicals are considered to play important roles. However, the medical effect of each radical, such as OH and O, is unknown. To examine the effect of each radical, selective production of radicals is needed. We developed selective production of radicals for biomedical treatment using a vacuum ultraviolet (VUV) light emitted from an excimer lamp. Selective irradiation of OH radicals can be achieved by irradiating the 172-nm VUV light from a Xe2 excimer lamp to a humid helium flow in a quartz tube. The water molecules are strongly photodissociated by the VUV light to produce OH radicals. A photochemical simulation for the selective OH production is developed to calculate the OH density. The calculated OH density is compared with OH density measured using laser-induced fluorescence (LIF). Selective production of other radicals than OH is also discussed.

  15. Influence of humidity on photochemical ozone generation with 172nm xenon excimer lamps

    NASA Astrophysics Data System (ADS)

    Salvermoser, M. J.; Kogelschatz, U.; Murnick, D. E.

    2009-08-01

    The reaction kinetics of photochemical ozone (O{3}) generation in humid air and oxygen (O{2}) using efficient, narrow band vacuum ultra violet (VUV) 172 nm xenon excimer lamps is discussed. Trace amounts of water (H{2}O) vapor in the process gas leads to hydroxyl (OH) and hydroperoxy (HO{2}) radical formation. These radicals drive a catalytic O{3} destruction cycle limiting O{3} saturation concentration. This catalytic O{3} destruction cycle was included into a quantitative kinetic model describing photochemical O{3} production. Experimental O{3} saturation concentrations obtained with coaxial VUV driven photochemical O{3} generators compare satisfactorily with the models predictions.

  16. Cell proliferation on UV-excimer lamp modified and grafted polytetrafluoroethylene

    NASA Astrophysics Data System (ADS)

    Švorčík, V.; Ročková, K.; Ratajová, E.; Heitz, J.; Huber, N.; Bäuerle, D.; Bačáková, L.; Dvořánková, B.; Hnatowicz, V.

    2004-04-01

    Polytetrafluoroethylene (PTFE) was modified by irradiation with 172 nm light from an UV-excimer lamp in reactive ammonia atmosphere. Then, the samples were exposed to aqueous solutions of amino acids (glycine, alanine and leucine). The samples were characterized by water contact angle measurement, UV-VIS spectroscopy and laser-induced fluorescence (LIF). The results indicate, that the amino acids are bound onto the polymer chain. The amount of incorporated amino acid is a decreasing function of its molecular size. By in vitro experiments it was shown that the incorporated amino acids support adhesion and proliferation of rat aortic smooth muscle cells and mouse embryonic 3T3 fibroblasts on the polymer surface. The maximum effect was observed for smallest molecule of glycine.

  17. Electrical and kinetical aspects of homogeneous dielectric-barrier discharge in xenon for excimer lamps

    SciTech Connect

    Belasri, A.; Harrache, Z.

    2010-12-15

    A pulsed dielectric-barrier discharge in xenon has been simulated for operating conditions typical to excimer lamps, in which the discharge is considered spatially homogeneous. The computer model developed is based on the xenon plasma chemistry, the circuit, and the Boltzmann equations. First, the validity of the physical model was checked and compared to experimental and theoretical works, and then the model is applied in the case of a sinusoidal voltage at period frequencies in the range of 50 kHz-2 MHz. The results obtained with the present description are in good agreement with experimental measurements and one-dimensional fluid prediction in terms of electrical characteristics and vacuum ultraviolet (vuv) emission. The effect of operation voltage, power source frequency, dielectric capacitance, as well as gas pressure on the discharge efficiency and the 172, 150, and 147 nm photon generation, under the typical experimental operating conditions and for the case of a sinusoidal applied voltage, have been investigated and discussed. Calculations suggest that the overall conversion efficiency from electrical energy to vuv emission in the lamp is greater than 38%, and it will be very affected at high power source frequency and high gas pressure with a significant dependence on the dielectric capacitance.

  18. Photochemically induced deposition of protective alumina coatings onto UV emitting phosphors for Xe excimer discharge lamps

    SciTech Connect

    Broxtermann, Mike Jüstel, Thomas

    2016-08-15

    Highlights: • A UV-reactor for the pH induced precipitation of inorganic material is described. • The photolysis of Azide (N{sub 3}{sup −}) leads to a steady pH increase used for precipitation. • A UV induced Al(OH){sub 3} precipitation is used to craft Al{sub 2}O{sub 3} coatings onto YPO{sub 4}:Bi. • The influence of Al{sub 2}O{sub 3} coated onto YPO{sub 4}:Bi with different thicknesses is discussed. • SEM, VUV-spectroscopy and ESA measurements were performed on Al{sub 2}O{sub 3} coated samples. - Abstract: This work concerns the particle coating of the UV-C emitting phosphor YPO{sub 4}:Bi, targeting a stability enhancement of the phosphor material for Xe excimer lamp operation. To this end, the material is coated by the wide band gap material Al{sub 2}O{sub 3}. In order to obtain a thin and homogeneous coating layer, a novel process based on the photochemical cleavage of NaN{sub 3} in water was developed. This results in a slow and continuous enhancement of the pH value due to ongoing NaOH formation, which results in the precipitation of Al(OH){sub 3} from an Al{sub 2}(SO{sub 4}){sub 3} {sub ×} 18H{sub 2}O solution. It turned out that the obtained particle coatings are of much better quality, i.e. homogeneity, compared to coatings made from a wet-chemical homogeneous precipitation process. The morphology and electrochemical properties of Al{sub 2}O{sub 3} coated YPO{sub 4}:Bi are discussed on the basis of optical spectroscopy, ESA measurements, and SEM/EDX investigations.

  19. Broadband 308 nm vibrational Raman spectroscopy of gaseous species using a potassium hydrogen phthalate liquid filter and polarization fluorescence suppression.

    PubMed

    Saunders, J E A; Davy, M H

    2010-01-01

    Broadband XeCl excimer lasers operating at 308 nm are not currently used in the field of gas phase vibrational Raman spectroscopy (VRS). An explanation as to why alternative wavelengths, and in particular tuneable, narrowband lasers are currently preferred for gas phase VRS is presented in addition to demonstrating a setup which makes the XeCl laser a viable alternative when considering excitation sources for VRS. A solution of potassium hydrogen phthalate is shown to be a practical low-pass liquid filter and to reduce substantially the effects of Rayleigh scattering on collected Raman spectra. The use of a commercial beam polarizer is also shown to be effective in suppressing background fluorescence that otherwise necessitates the use of expensive tuneable, narrowband lasers when performing VRS with sources of background fluorescence. Finally, an unconventional excitation beam arrangement is shown to produce viable Raman spectra from which species concentrations and distributions can be determined.

  20. Improving vacuum-UV (VUV) photolysis of organic compounds in water with a phosphor converted xenon excimer lamp emitting at 193 nm.

    PubMed

    Schulze-Hennings, U; Pötschke, L; Wietor, C; Bringmann, S; Braun, N; Hayashi, D; Linnemann, V; Pinnekamp, J

    A novel vacuum ultraviolet excimer lamp emitting light at 193 nm was used to investigate the degradation of organic micropollutants in ultrapure water and wastewater treatment plant (WWTP) effluent. Overall, light at 193 nm proved to be efficient to degrade the investigated micropollutants (diclofenac, diatrizoic acid, sulfamethoxazole). Experiments with WWTP effluent proved the ability of radiation at 193 nm to degrade micropollutants which are hardly removed with commonly used oxidation technologies like ozonation (diatrizoic acid, ethylenediaminetetraacetic acid, perfluorooctanoic acid, and perfluorooctanesulfonic acid).

  1. Study of the first pulse of Ne-Xe-HCl dielectric barrier discharge for the excimer lamp

    SciTech Connect

    Belasri, A.; Bendella, S.; Baba-Hamed, T.

    2008-05-15

    A global one-dimensional model of a dielectric barrier discharge which includes the sheath region and the positive column was developed. The model was used to study the electrical properties under operating conditions of the vacuum ultraviolet excimer lamp and to understand the basic processes of plasma kinetics. A 0.5 cm interelectrode gap distance is filled with a Ne-Xe-HCl mixture. Time variations of the charged particles and excited species in the positive column were described. Then the one-dimensional model was used in the cathode region to illustrate (i) the spatio-temporal behavior of electronic and ionic densities and the electric field, and (ii) the time variation of the voltage, the current, and secondary currents due to ion and photon ({lambda}=172 nm) impact on the cathode. It shows a good resolution inside the sheath at high pressure and it correctly predicts the waveform of the discharge behavior. The obtained results have been discussed and analyzed.

  2. Quantum yield of chlorine-atom formation in the photodissociation of chlorine peroxide (ClOOCl) at 308 nm

    NASA Technical Reports Server (NTRS)

    Molina, M. J.; Colussi, A. J.; Molina, L. T.; Schindler, R. N.; Tso, T.-L.

    1990-01-01

    The production of Cl atoms in the laser flash photolysis of ClOOCl at 308 nm has been investigated by time-resolved atomic resonance fluorescence at 235 K. A value of phi = 1.03 +/-0.12 has been obtained for the primary quantum yield based on an absorption cross section ratio sigma(245)/phi(308) = 22 for ClOOCl at 245 and 308 nm.

  3. Engineering of a highly efficient Xe₂*-excilamp (xenon excimer lamp, λmax=172 nm, η=40%) and qualitative comparison to a low-pressure mercury lamp (LP-Hg, λ=185/254 nm) for water purification.

    PubMed

    Al-Gharabli, Samer; Engeßer, Patrick; Gera, Diana; Klein, Sandra; Oppenländer, Thomas

    2016-02-01

    Excilamps are mercury-free gas-discharge sources of non-coherent VUV or UV radiation with high radiant power and a long lifetime. The most efficient excilamp that is currently available on the market is a VUV xenon excilamp system (Xe2(*)-excimer lamp, λ(max) = 172 nm) with a stated radiant efficiency η of 40% at an electrical input power P(el) of 20 W, 50 W or 100 W. In this paper, the use of this highly efficient Xe2(*)-excilamp (P(el) = 20 W) for water treatment is demonstrated using a recirculating laboratory photoreactor system with negative radiation geometry. The efficiency in the 172 nm initiated bleaching of aqueous solutions of Rhodamine B is compared to that initiated by a common low-pressure mercury (LP-Hg) lamp (185 nm, TNN 15/32). The dependence of the pseudo zero order rate constant k´ of decolorization of RhB on the flow rate and on the initial concentration of RhB was investigated. Both lamps exhibited dependences of k´ on the initial concentration of RhB, which represents a typical saturation kinetical behavior. The saturation kinetics was very prominent in the case of the Xe2(*)-excilamp. Also, the Xe2(*)-excilamp treatment exhibited a significant influence on the flow rate of the RhB aqueous solution, which was not the case during the LP-Hg lamp initiated bleaching of RhB. The results of this paper demonstrate that Xe2(*)-excilamps can be used for VUV-initiated water purification. However, to reach the maximum efficacy of the Xe2(*)-excilamp for photo-initiated water purification further engineering optimization of the photoreactor concept is necessary.

  4. Excimer lasers

    NASA Technical Reports Server (NTRS)

    Palmer, A. J.; Hess, L. D.; Stephens, R. R.

    1976-01-01

    A theoretical and experimental investigation into the possibility of achieving CW discharge pumped excimer laser oscillation is reported. Detailed theoretical modeling of capillary discharge pumping of the XeF and KXe and K2 excimer systems was carried out which predicted the required discharge parameters for reaching laser threshold on these systems. Capillary discharge pumping of the XeF excimer system was investigated experimentally. The experiments revealed a lower excimer level population density than predicted theoretically by about an order of magnitude. The experiments also revealed a fluorine consumption problem in the discharge in agreement with theory.

  5. Pulsed excimer laser angioplasty of human cadaveric arteries.

    PubMed

    Farrell, E M; Higginson, L A; Nip, W S; Walley, V M; Keon, W J

    1986-02-01

    Laser angioplasty has been limited by the lack of precise control of thermal and acoustic vascular injury. Pulsed excimer lasers, by contrast, have a capacity to affect target tissue without heat dispersion or damage to surrounding structures. The ablative properties of three excimer wavelengths, krypton fluoride (249 nm), xenon chloride (308 nm), and xenon fluoride (351 nm), were investigated with the use of fresh human cadaveric normal and atherosclerotic femoral arteries. Light and electron microscopy demonstrated clean cuts with histologically normal edges. There was no evidence of either thermal or acoustic damage with any of the wavelengths studied. The depth of ablation varied directly with the number of pulses and inversely with tissue density while the incision width remained constant. The excimer laser appears to offer significant advantages over its conventional counterparts for the ablation of atherosclerotic plaque.

  6. Analytical Characterization of CFRP Laser Treated by Excimer Laser Radiation

    NASA Astrophysics Data System (ADS)

    Kreling, S.; Fischer, F.; Delmdahl, R.; Gäbler, F.; Dilger, K.

    Due to the increasing interest in lightweight structures, carbon-fiber reinforced plastics are increasingly applied, especially in the transportation industry. An interesting technology for joining these materials is adhesive bonding due to numerous advantages compared to conventional techniques like riveting. However, to achieve a strong and durable bond, surface pre-treatment is necessary to remove residues of release agents that are transferred to the surface during manufacturing. This paper describes analytical experiments, namely SEM and XPS, performed on CFRP surfaces pre-treated with 308 nm excimer laser radiation.

  7. Excimer laser: a module of the alopecia areata common protocol.

    PubMed

    McMichael, Amy J

    2013-12-01

    Alopecia areata (AA) is an autoimmune condition characterized by T cell-mediated attack of the hair follicle. The inciting antigenic stimulus is unknown. A dense perbulbar lymphocytic infiltrate and reproducible immunologic abnormalities are hallmark features of the condition. The cellular infiltrate primarily consists of activated T lymphocytes and antigen-presenting Langerhans cells. The xenon chloride excimer laser emits its total energy at the wavelength of 308 nm and therefore is regarded as a "super-narrowband" UVB light source. Excimer laser treatment is highly effective in psoriasis, another T cell-mediated disorder that shares many immunologic features with AA. The excimer laser is superior in inducing T cell apoptosis in vitro compared with narrowband UVB, with paralleled improved clinical efficacy. The excimer laser has been used successfully in patients with AA. In this context, evaluation of the potential benefit of 308-nm excimer laser therapy in the treatment of AA is clinically warranted. Herein, the use of a common treatment protocol with a specifically designed module to study the outcome of excimer laser treatment on moderate-to-severe scalp AA in adults is described.

  8. Excimer lasers

    NASA Technical Reports Server (NTRS)

    Palmer, A. J.; Hess, L. D.; Stephens, R. R.; Pepper, D. M.

    1977-01-01

    The results of a two-year investigation into the possibility of developing continuous wave excimer lasers are reported. The program included the evaluation and selection of candidate molecular systems and discharge pumping techniques. The K Ar/K2 excimer dimer molecules and the xenon fluoride excimer molecule were selected for study; each used a transverse and capillary discharges pumping technique. Experimental and theoretical studies of each of the two discharge techniques applied to each of the two molecular systems are reported. Discharge stability and fluorine consumption were found to be the principle impediments to extending the XeF excimer laser into the continuous wave regime. Potassium vapor handling problems were the principal difficulty in achieving laser action on the K Ar/K2 system. Of the four molecular systems and pumping techniques explored, the capillary discharge pumped K Ar/K2 system appears to be the most likely candidate for demonstrating continuous wave excimer laser action primarily because of its predicted lower pumping threshold and a demonstrated discharge stability advantage.

  9. Clinical experience with peripheral excimer laser angioplasty

    NASA Astrophysics Data System (ADS)

    Visona, Adriana; Cecchetti, Walter; Liessi, Guido; Miserocchi, Luigi; Bonanome, Andrea; Lusiani, Luigi; Mayellaro, Valeria; Pagnan, Antonio

    1993-06-01

    We used an excimer laser system (xenon-chloride at the wavelength of 308 nm) to treat totally occluded peripheral vessels in 71 patients. Energy was delivered through a multifiber catheter, which combines 12 (7F) or 18 (9F) fibers (260 (mu) diameter each), concentrically arranged. Balloon dilatation was associated to complete the procedure in 84% of the cases. The immediate success rate was 97%. The cumulative patency rate was 49% at one year. The major problems with this system were that the stiff multifiber tips caused dissections, and spasm; dead space/active space ratio of the catheter was unfavorable, allowing mechanical `dottering;' the maximum lumen obtained was considered inadequate. After this three year period, the goal of our clinical laser program is to develop a stand alone laser technique by employing a multifiber catheter which combines 130 - 150 fibers 100 (mu) diameter each, and features a quartz coated distal tip.

  10. Percutaneous transluminal excimer laser angioplasty in total peripheral artery occlusion in man

    SciTech Connect

    Wollenek, G.; Laufer, G.; Grabenwoeger, F.

    1988-01-01

    Laser angioplasty and laser-assisted angioplasty have become a clinical reality. Producing sharply defined borders of the ablated area with minimal adjacent thermal damage, excimer lasers offer several proven and some potential advantages over conventional systems. To evaluate the feasibility of excimer laser angioplasty, we have treated one patient using 308-nm radiation via a bare fiber in direct contact with the total occlusion of a right femoral artery. The lesion was successfully recanalized, thus allowing easy passage of the balloon catheter and subsequent dilatation. This percutaneous laser recanalization of an occluded peripheral artery is one of the first to be done in man using excimer laser radiation, thus demonstrating that the technique is feasible and the system is potentially useful.

  11. Gas-phase photodissociation of CH{sub 3}COCN at 308 nm by time-resolved Fourier-transform infrared emission spectroscopy

    SciTech Connect

    Yeh, Yu-Ying; Chao, Meng-Hsuan; Tsai, Po-Yu; Chang, Yuan-Bin; Tsai, Ming-Tsang; Lin, King-Chuen

    2012-01-28

    By using time-resolved Fourier-transform infrared emission spectroscopy, the fragments of HCN(v= 1, 2) and CO(v= 1-3) are detected in one-photon dissociation of acetyl cyanide (CH{sub 3}COCN) at 308 nm. The S{sub 1}(A'), {sup 1}(n{sub O}, {pi}*{sub CO}) state at 308 nm has a radiative lifetime of 0.46 {+-} 0.01 {mu}s, long enough to allow for Ar collisions that induce internal conversion and enhance the fragment yields. The rate constant of Ar collision-induced internal conversion is estimated to be (1-7) x 10{sup -12} cm{sup 3} molecule{sup -1} s{sup -1}. The measurements of O{sub 2} dependence exclude the production possibility of these fragments via intersystem crossing. The high-resolution spectra of HCN and CO are analyzed to determine the ro-vibrational energy deposition of 81 {+-} 7 and 32 {+-} 3 kJ/mol, respectively. With the aid of ab initio calculations, a two-body dissociation on the energetic ground state is favored leading to HCN + CH{sub 2}CO, in which the CH{sub 2}CO moiety may further undergo secondary dissociation to release CO. The production of CO{sub 2} in the reaction with O{sub 2} confirms existence of CH{sub 2} and a secondary reaction product of CO. The HNC fragment is identified but cannot be assigned, as restricted to a poor signal-to-noise ratio. Because of insufficient excitation energy at 308 nm, the CN and CH{sub 3} fragments that dominate the dissociation products at 193 nm are not detected.

  12. Influence of the chlorine concentration on the radiation efficiency of a XeCl exciplex lamp

    SciTech Connect

    Avtaeva, S. V.; Sosnin, E. A.; Saghi, B.; Panarin, V. A.; Rahmani, B.

    2013-09-15

    The influence of the chlorine concentration on the radiation efficiency of coaxial exciplex lamps (excilamps) excited by a dielectric barrier discharge (DBD) in binary Xe-Cl{sub 2} mixtures at pressures of 240–250 Torr is investigated experimentally and theoretically. The experiments were carried out at Cl{sub 2} concentrations in the range of 0.01–1%. The DBD characteristics were calculated in the framework of a one-dimensional hydrodynamic model at Cl{sub 2} concentrations in the range of 0.1–5%. It is found that the radiation intensities of the emission bands of Xe*{sub 2}(172 nm) and XeCl* (308 nm) are comparable when the chlorine concentration in the mixture is in the range of 0.01–0.1%. In this case, in the mixture, the radiation intensity of the Xe*{sub 2} molecule rapidly decreases with increasing Cl{sub 2} concentration and, at a chlorine concentration of ≥0.2%, the radiation of the B → X band of XeCl* molecules with a peak at 308 nm dominates in the discharge radiation. The radiation efficiency of this band reaches its maximum value at chlorine concentrations in the range of 0.4–0.5%. The calculated efficiencies of DBD radiation exceed those obtained experimentally. This is due to limitations of the one-dimensional model, which assumes the discharge to be uniform in the transverse direction, whereas the actual excilamp discharge is highly inhomogeneous. The influence of the chlorine concentration on the properties of the DBD plasma in binary Xe-Cl{sub 2} mixtures is studied numerically. It is shown that an increase in the Cl{sub 2} concentration in the mixture leads to the attachment of electrons to chlorine atoms and a decrease in the electron density and discharge conductivity. As a result, the electric field and the voltage drop across the discharge gap increase, which, in turn, leads to an increase in the average electron energy and the probability of dissociation of Cl{sub 2} molecules and ionization of Xe atoms and Cl{sub 2} molecules

  13. Modeling boron profiles in silicon after pulsed excimer laser annealing

    SciTech Connect

    Hackenberg, M.; Huet, K.; Negru, R.; Venturini, J.; Fisicaro, G.; La Magna, A.; Pichler, P.

    2012-11-06

    In this work, we investigated four possible mechanisms which were candidates to explain the shape of boron profiles after ion implantation and melting excimer laser annealing in silicon. A laser with a wavelength of 308 nm and a pulse duration of {approx}180 ns was used. To simulate this process, an existing model for the temperature and phase evolution was complemented with equations for the migration of dopants. Outdiffusion, thermodiffusion, segregation, and adsorption were investigated as possible mechanisms. As a result, we found that outdiffusion and segregation can be excluded as major mechanisms. Thermodiffusion as well as adsorption could both reproduce the build-up at low melt depths, but only adsorption the one at deeper melt depths. In both cases, ion beam mixing during SIMS measurement had to be taken into account to reproduce the measured profiles.

  14. Note: Photodissociation of CH3COCN at 308 nm by time-resolved Fourier-transform infrared emission spectroscopy: Is CO a primary or secondary product?

    NASA Astrophysics Data System (ADS)

    Tsai, Po-Yu; Lin, King-Chuen

    2013-06-01

    This Note aims to clarify the source of CO in photodissociation of acetyl cyanide (CH3COCN) at 308 nm. From the theoretical aspects, a new pathway via isomerization transition state (TS) at 391 ± 8 kJ/mol is found leading to the CO + CH3NC products. An amount of 60% reactant molecules at 300 K is estimated to successfully surpass the average TS barrier lying above the excitation energy by 3.5 kJ/mol. Further, a prior distribution method is conducted to characterize the vibrational energy distribution of CO on a statistical basis. The pathway to CH3NC + CO yields a vibrational branching ratio (v = 0:v = 1:v = 2:v = 3˜0.63:0.25:0.093:0.032) in excellent agreement with the observation (0.62:0.25:0.09:0.05).

  15. Calcified lesion modeling for excimer laser ablation

    NASA Astrophysics Data System (ADS)

    Scott, Holly A.; Archuleta, Andrew; Splinter, Robert

    2009-06-01

    Objective: Develop a representative calcium target model to evaluate penetration of calcified plaque lesions during atherectomy procedures using 308 nm Excimer laser ablation. Materials and Methods: An in-vitro model representing human calcified plaque was analyzed using Plaster-of-Paris and cement based composite materials as well as a fibrinogen model. The materials were tested for mechanical consistency. The most likely candidate(s) resulting from initial mechanical and chemical screening was submitted for ablation testing. The penetration rate of specific multi-fiber catheter designs and a single fiber probe was obtained and compared to that in human cadaver calcified plaque. The effects of lasing parameters and catheter tip design on penetration speed in a representative calcified model were verified against the results in human cadaver specimens. Results: In Plaster of Paris, the best penetration was obtained using the single fiber tip configuration operating at 100 Fluence, 120 Hz. Calcified human lesions are twice as hard, twice as elastic as and much more complex than Plaster of Paris. Penetration of human calcified specimens was highly inconsistent and varied significantly from specimen to specimen and within individual specimens. Conclusions: Although Plaster of Paris demonstrated predictable increases in penetration with higher energy density and repetition rate, it can not be considered a totally representative laser ablation model for calcified lesions. This is in part due to the more heterogeneous nature and higher density composition of cadaver intravascular human calcified occlusions. Further testing will require a more representative model of human calcified lesions.

  16. Primary success and one-year followup of percutaneous peripheral excimer laser angioplasty

    NASA Astrophysics Data System (ADS)

    Visona, Adriana; Liessi, Guido; Miserocchi, Luigi; Bonanome, Andrea; Lusiani, Luigi; Breggion, Giovanni; Pagnan, Antonio

    1992-08-01

    Excimer laser angioplasty was performed in 59 patients (44 males and 17 females, mean age 63 +/- 9 years, range 39 - 77) affected by peripheral vascular disease. Fifty patients had a total occlusion of the superficial femoral artery, three of the iliac artery, and one of the popliteal artery; seven patients showed a subocclusive stenosis of the superficial femoral artery. A commercial excimer laser (Technolas Max-10) was used at the Xenon-Chloride wavelength of 308 nm. The laser operated at 120 ns pulse length and at 20 Hz repetition rate. Applied energy fluence was 20 mJ/pulse. The energy was delivered through a multifiber catheter, which combines 12 (7F) or 18 (9F) fibers (260 micron diameter each), concentrically arranged. Balloon dilatation was associated in 51 patients. Successful recanalization was obtained in 59 out of 61 patients (97%). Failure to recanalize the occluded arteries occurred in two cases, and was due to dissection. Early thrombosis and reocclusion (within 48 hours) was observed in five patients. The cumulative patency rate was 56% at one year. On the basis of these results, excimer laser assisted angioplasty seems a feasible and safe procedure. However, this technique did not solve the restenosis problem. A wide application of excimer laser as a stand alone approach can be foreseen for treatment of peripheral vascular disease.

  17. Application of optical tweezers and excimer laser to study protoplast fusion

    NASA Astrophysics Data System (ADS)

    Kantawang, Titirat; Samipak, Sompid; Limtrakul, Jumras; Chattham, Nattaporn

    2015-07-01

    Protoplast fusion is a physical phenomenon that two protoplasts come in contact and fuse together. Doing so, it is possible to combine specific genes from one protoplast to another during fusion such as drought resistance and disease resistance. There are a few possible methods to induce protoplast fusion, for example, electrofusion and chemical fusion. In this study, chemical fusion was performed with laser applied as an external force to enhance rate of fusion and observed under a microscope. Optical tweezers (1064 nm with 100X objective N.A. 1.3) and excimer laser (308 nm LMU-40X-UVB objective) were set with a Nikon Ti-U inverted microscope. Samples were prepared by soaking in hypertonic solution in order to induce cell plasmolysis. Elodea Canadensis and Allium cepa plasmolysed leaves were cut and observed under microscope. Concentration of solution was varied to induce difference turgor pressures on protoplasts pushing at cell wall. Free protoplasts in solution were trapped by optical tweezers to study the effect of Polyethylene glycol (PEG) solution. PEG was diluted by Ca+ solution during the process to induced protoplast cell contact and fusion. Possibility of protoplast fusion by excimer laser was investigated and found possible. Here we report a novel tool for plant cell fusion using excimer laser. Plant growth after cell fusion is currently conducted.

  18. Elaboration of excimer lasers dosimetry for bone and meniscus cutting and drilling using optical fibers

    NASA Astrophysics Data System (ADS)

    Jahn, Renate; Dressel, Martin; Neu, Walter; Jungbluth, Karl-Heinz

    1991-05-01

    In order to optimize bone and cartilage ablation, various excimer laser systems at 308 nm wavelength (pulse width 28 ns, 60 ns, 300 ns) and tapered fibers (core diameter 400 micrometers , 600 micrometers , 1000 micrometers ) were combined. By varying the major parameters such as fluence, pulselength, repetition rate, fiber diameter, medium, manner of application (drilling, cutting); analysis was made of the interaction of the excimer laser beam with different organic material (meniscus, bone tissue). More than 300 cuts and drillings have been realized with different parameters. The ablation rate mainly depends on fluence, repetition rate and pulse duration. The achieved ablation rate was 3 micrometers /pulse in bone. The drilling speed of the meniscus was 6 mm/s. The samples showed no carbonization at all, when being cut or drilled in liquid medium. This might be a breakthrough in fiber guided excimer laser surgery. From these and further experiments the authors obtained the dosimetry, which will be the basis for the elaboration of necessary operation guidelines for accident surgery.

  19. Endovascular excimer laser atherectomy techniques to treat complex peripheral vascular disease: an orderly process.

    PubMed

    Garnic, J Daniel; Hurwitz, Andrew S

    2005-12-01

    Peripheral vascular disease represents the largest obstructive subsegment within the vascular system. Advances in equipment, techniques, biochemical treatments, and the influx of multiple specialties into this arena indicate a coming tidal wave of change to the standard treatment plan for patients with claudication and especially critical limb ischemia. Initial attempts in the 1980s to utilize the "laser" to treat peripheral vascular disease led to a clinical debacle: wavelengths and methods were not optimized; tissue heating was excessive, resulting in restenosis. Since then the "laser" has fallen from grace for endovascular treatment, although it has an infinite set of potential wavelengths, energy levels, and delivery methods. The xenon chloride, excimer laser, a pulsed 308-nm system, has overcome many of these early catastrophes. The long, ongoing success of this method of photoablating thrombus and plaque represents a true step forward in the endovascular treatment of occlusive disease. Although only a tool, the excimer laser provides a means to utilize electromagnetic energy instead of shearing mechanical force to resolve occlusions. With its active element at the tip, the excimer laser requires much less mechanical translation force to cross total occlusions, find the distal lumen, and thereby cause less plaque destabilization. In addition, removing the firm surface layer of plaque, decapping, and some of the plaque volume, debulking, exposes the softer subsegments of the plaque to balloon angioplasty. Utilizing this method, more complex lesions can be approached safely, with a high likelihood of successful revascularization and a low risk of potentially limb-threatening complication.

  20. Colouring fabrics with excimer lasers to simulate encoded images: the case of the Shroud of Turin

    NASA Astrophysics Data System (ADS)

    Di Lazzaro, P.; Baldacchini, G.; Fanti, G.; Murra, D.; Santoni, A.

    2008-10-01

    The faint body image embedded into the Turin Shroud has not yet explained by traditional science. We present experimental results of excimer laser irradiation (wavelengths 308 nm and 193 nm) of a raw linen fabric and of a linen cloth, seeking for a possible mechanism of image formation. The permanent coloration of both linens is a threshold effect on the laser beam intensity and it can be achieved only in a surprisingly narrow range of irradiation parameters: the shorter the wavelength, the narrower the range. We also obtained the first direct evidence of latent images impressed on linen that appear in a relatively long period (one year) after a laser irradiation that at first did not generate a clear image. The results are compared to the characteristics of the Turin Shroud, commenting the possibility that a burst of directional ultraviolet radiation may have played a role in the formation of the Shroud image.

  1. Coloring linens with excimer lasers to simulate the body image of the Turin Shroud

    NASA Astrophysics Data System (ADS)

    Baldacchini, Giuseppe; di Lazzaro, Paolo; Murra, Daniele; Fanti, Giulio

    2008-03-01

    The body image of the Turin Shroud has not yet been explained by traditional science; so a great interest in a possible mechanism of image formation still exists. We present preliminary results of excimer laser irradiation (wavelength of 308 nm) of a raw linen fabric and of a linen cloth. The permanent coloration of both linens is a threshold effect of the laser beam intensity, and it can be achieved only in a narrow range of irradiation parameters, which are strongly dependent on the pulse width and time sequence of laser shots. We also obtained the first direct evidence of latent images impressed on linen that appear in a relatively long period (one year) after laser irradiation that at first did not generate a clear image. The results are compared with the characteristics of the Turin Shroud, reflecting the possibility that a burst of directional ultraviolet radiation may have played a role in the formation of the Shroud image.

  2. Excimer laser coronary angioplasty: relative risk analysis of clinical results

    NASA Astrophysics Data System (ADS)

    Bittl, John A.

    1992-08-01

    Reports of successful use of excimer laser coronary angioplasty for complex coronary artery disease abound, yet firm indications for its use have not been defined. We attempted to treat 858 coronary stenoses in 764 consecutive patients (mean age 61 years; range 32 - 91 years; 75% men; 76% with Class III or IV angina) with excimer laser angioplasty at 308 nm. Successful treatment was achieved in 86% of patients, as indicated by excimer laser angioplasty, we used relative risk analysis. This showed that certain angiographic features, such as lesions at a vessel bifurcation (odds ratio, OR equals 0.46; 95% confidence interval 0.23, 0.88; P equals 0.017;) or in a tortuous segment (OR equals 0.54; 95% CI equals 0.34, 0.88; P equals 0.041), have decreased likelihood of clinical success. On the other hand, ostial stenoses (OR equals 1.06; 95% CI equals 0.44, 2.56, P equals 0.903) and saphenous vein graft lesions (OR equals 2.17; 95% CI equals 0.98, 4.82; P equals 0.051) have acceptable success rates. Diffuse disease (> 20 mm), total occlusions and calcified lesions were treated as successfully as all other lesion types. Successful treatment with excimer laser coronary angioplasty was also achieved in almost all patients (15/16) who had a prior unsuccessful attempt at balloon angioplasty in the lesion was crossed with a guidewire yet resists either balloon catheter passage or full dilatation. Follow-up angiography was obtained in 70% of eligible patients. Angiographic restenosis, defined by > 50% stenosis, was seen in 60% of patients. Relative risk analysis showed an increased risk of restenosis when adjunctive balloon angioplasty was not used (OR equals 1.68; 95% CI equals 1.02, 2.28; P equals 0.039). Other variables known to affect the outcome of balloon angioplasty, such as lesion length or stenosis in degenerated saphenous vein bypass graft, did not influence the

  3. Excimer Lasers In Medicine

    NASA Astrophysics Data System (ADS)

    Tittel, Frank K.; Saidi, Iyad S.; Pettit, George H.; Wisoff, P. J.; Sauerbrey, Roland A.

    1989-06-01

    Excimer lasers emit light energy, short optical pulses at ultraviolet wavelengths, that results in a unique laser tissue interaction. This has led to an increasing number of studies into medical applications of these lasers in fields such as ophthalmology, urology, cardiology and neurology.

  4. Comparative shock wave analysis during corneal ablation with an excimer laser, picosecond laser, and femtosecond laser

    NASA Astrophysics Data System (ADS)

    Krueger, Ronald R.; Juhasz, Tibor

    1995-05-01

    With the event of topographic steep central islands following excimer laser surgery and the potential damage to the corneal endothelium, shock waves are playing an increasingly important role in laser refractive surgery. With this in mind, we performed a comparative shock wave analysis in corneal tissue using an excimer laser, picosecond laser, and femtosecond laser. We used a Lambda Physik excimer laser at 308 nm wavelength, a Nd:YLF picosecond laser at 1053 nm wavelength and a synchronously pumped linear cavity femtosecond laser at 630 nm wavelength. The pulse widths of the corresponding lasers were 8 ns, 18 ps, 150 fs, respectively. The energy density of irradiation was 2.5 to 8 times the threshold level being 2 J/cm2 (excimer laser), 86 J/cm2 (picosecond laser) and 10.3 J/cm2 (femtosecond laser). Shock wave dynamics were analyzed using time-resolved photography on a nanosecond time scale using the picosecond laser in corneal tissue, water and air. Shock wave dynamics using the femtosecond laser were studied in water only while the excimer laser induced shock wave during corneal ablation was studied in air only. We found the dynamics of shock waves to be similar in water and corneal tissue indicating that water is a good model to investigate shock wave effects in the cornea. The magnitude of the shock wave velocity and pressure decays over time to that of a sound wave. The distance over which it decays is 3 mm in air with the excimer laser and 600 - 700 micrometers in air with the picosecond laser. In water, the picosecond laser shock wave decays over a distance of 150 micrometers compared to the femtosecond laser shock wave which decays over a distance of 30 micrometers . Overall the excimer laser shock wave propagates 5 times further than that of the picosecond laser and the picosecond laser shock wave propagates 5 times further than that of the femtosecond laser. In this preliminary comparison, the time and distance for shock wave decay appears to be directly

  5. Pulsed excimer laser processing

    NASA Technical Reports Server (NTRS)

    Wong, D.

    1985-01-01

    The status of pulsed excimer laser processing of PV cells is presented. The cost effective feasibility of fabricating high efficiency solar cells on Czochralski wafers using a pulsed excimer laser for junction formation, surface passivation, and front metallization. Laser annealing results were promising with the best AR coated cell having an efficiency of 16.1%. Better results would be expected with larger laser spot size because there was some degradation in open circuit voltage caused by laser spot overlap and edge effects. Surface heating and photolytic decomposition by the laser was used to deposit tungsten from the reaction of tungsten hexafluoride and hydrogen. The line widths were 5 to 10 mils, and the depositions passed the tape adhesion test. Thinner lines are practical using an optimized optical system.

  6. Pulsed excimer laser processing

    NASA Astrophysics Data System (ADS)

    Wong, D.

    1985-06-01

    The status of pulsed excimer laser processing of PV cells is presented. The cost effective feasibility of fabricating high efficiency solar cells on Czochralski wafers using a pulsed excimer laser for junction formation, surface passivation, and front metallization. Laser annealing results were promising with the best AR coated cell having an efficiency of 16.1%. Better results would be expected with larger laser spot size because there was some degradation in open circuit voltage caused by laser spot overlap and edge effects. Surface heating and photolytic decomposition by the laser was used to deposit tungsten from the reaction of tungsten hexafluoride and hydrogen. The line widths were 5 to 10 mils, and the depositions passed the tape adhesion test. Thinner lines are practical using an optimized optical system.

  7. Effects of XeCl excimer lasers and fluoride application on artificial caries-like lesions

    NASA Astrophysics Data System (ADS)

    Wilder-Smith, Petra B. B.; Phan, T.; Liaw, Lih-Huei L.; Berns, Michael W.

    1994-09-01

    In this study the affects of a pulsed excimer laser emitting at 308 nm (XeCl) on enamel susceptibility to artificial caries-like lesions were investigated. Additional effects of fluoride (F) application were also studied and SEC examinations performed. Sixty-four extracted human molar teeth were coated with acid resistant varnish leaving four windows, then sectioned, leaving one window on each tooth quarter. The windows were treated in one of the following ways: untreated (control), or lased, or exposed to 4 min. APF (1.23% F) before lasing, or exposed to 4 min. APF (1.23% F) after lasing. After lasing, microhardness profiles were obtained and SEM was performed. Caries resistance was generally increased at moderate fluences. F application combined with lasing enhanced caries resistance at some parameters. SEM showed effects ranging from minimal to localized effects to extended glazing. Pulsed excimer laser irradiation, especially combined with topical F application can inhibit development of artificial caries-like lesions.

  8. Short-pulse excimer laser performances and its applications: I. ophthamology

    NASA Astrophysics Data System (ADS)

    Przybylski, Marius; Simon, Gabriel

    1997-05-01

    A new very small powerful air-cooled excimer laser (193, 248, 308 nm) with metal-ceramic technology was developed by ATL Lasertechnik in Germany. The laser won 1995 Prize for the best innovation awarded by German federal states of Berlin & Brandenburg. The pulse energy of 10 - 20 mJ at high rep rates (200 - 500 Hz) from an active volume of only 1 cm3 are reached. The raw laser beam produces energy density of > 100 mJ/cm2 which is comparable to the performance of standard (large) excimer lasers. Its very short pulse length (3 ns), permits extremely high peak power density (30 MW/cm2). The ATLEX SP laser uses a new type of pre-ionization technique providing high beam homogeneity at low discharge voltages. Small footprint and weight, low operation costs opens up new industrial (micro-machining) and biomedical applications. Recently the ATLEX SP laser (193 nm) has been used for corneal refractive surgery. The setup consists of splitting a 193 nm laser beam into couples of beams which simultaneously ablates the corneal surface in a symmetrical scan-like fashion. Refractive changes up to 20 diopters were realized. Results of an analysis by corneal topography showed homogeneous ablation throughout the entire ablation zone.

  9. The Results of Raster-Scan Laser Conditioning Studies on DKDP Triplers Using Nd: YAG and Excimer Lasers

    SciTech Connect

    Runkel, M; Neeb, K; Staggs, M; Auerbach, J; Burnham, A

    2001-11-01

    In this paper we present the results of damage tests performed at 1064 and 355-nm at 8-10 ns on conventional and rapid growth DKDP tripler crystals. The crystals were laser conditioned prior to damage testing by raster scanning using either Nd:YAG (1064 and 355 nm, 8-10ns) or excimer lasers at 248, 308 or 351 nm with pulse durations of approximately 30-47 ns. The results show that it is possible to attain increases in 355-nm damage probability fluences of 2X for excimer conditioning at 248 and 308 nm. However these wavelengths can induce absorption sufficient to induce bulk fracture by thermal shock when impurities such as arsenic, rubidium and sulfur are present in the crystals in sufficient quantity. Tests to evaluate the efficiency of 351-nm conditioning (XeF excimer) show improvements of 2X and that thermal fracture by induced absorption is not a problem. We also discuss our recent discovery that low fluence raster scanning at UV wavelengths leads to 1064-nm damage thresholds of over 100 J/cm{sup 2} (10-ns pulses).

  10. Excimer laser ablation of thick SiOx-films: Etch rate measurements and simulation of the ablation threshold

    NASA Astrophysics Data System (ADS)

    Ihlemann, J.; Meinertz, J.; Danev, G.

    2012-08-01

    Excimer laser ablation of 4.5 μm thick SiOx-films with x ≈ 1 is investigated at 193 nm, 248 nm, and 308 nm. Strong absorption enables precisely tunable removal depths. The ablation rates correlate with laser penetration depths calculated from low level absorption coefficients. The experimental ablation thresholds are in agreement with numerical simulations on the basis of linear absorption and one-dimensional heat flow. This behaviour is similar to that of strongly UV-absorbing polymers, leading to well controllable micro machining prospects. After laser processing, SiOx can be converted to SiO2, opening a route to laser based fabrication of micro optical components.

  11. Direct carbide synthesis by multipulse excimer laser treatment of Ti samples in ambient CH4 gas at superatmospheric pressure

    NASA Astrophysics Data System (ADS)

    Mihailescu, I. N.; Chitica, N.; Teodorescu, V. S.; Popescu, M.; De Giorgi, M. L.; Luches, A.; Perrone, A.; Boulmer-Leborgne, Ch.; Hermann, J.; Dubreuil, B.; Udrea, S.; Barborica, A.; Iova, I.

    1994-05-01

    Successful carbidation of Ti in a layer forming on the surface of a Ti sample submitted to multipulse excimer (λ=308 nm) laser treatment in CH4 at a slightly superatmospheric pressure is reported. The layer is only surface contaminated with oxygen while its main part consists of fcc TiC. The layer apparently ends with a tail of carbides with low C content, extending deeper into the sample's bulk. The characteristics of the synthesized layer are suggested to be related to the peculiarities of the chemical synthesis which are enhanced by gas propulsion into a melted layer under the recoil action of a plasma evolving in front of the sample. A cavitation mechanism inside the melted surface layer in order to account for plasma initiation is proposed. This mechanism also facilitates the strong substance propulsion into the sample's bulk.

  12. Control of structure and electric properties of amorphous organic semiconductive thin films prepared by excimer laser ablation

    NASA Astrophysics Data System (ADS)

    Nishio, S.; Sato, H.; Yamabe, T.

    Excimer laser ablation (ELA) of 3,4,9,10-perylene-tetracarboxylic dianhydride (PTCDA) with ArF (193 nm), KrF (248 nm), XeCl (308 nm), and XeF (351 nm) beams under optimized conditions enables us to obtain organic semiconductor thin films with various structures such as amorphous carbon, polyperinaphthalene (PPN), and PTCDA itself. Electric conductivity and carrier species of the films depend strongly on the ablation wavelength, fluence, substrate temperature, and ambient vapor species. It is found that electric conductivities of the films are controllable, ranging from 10-6 to 101 Scm-1 with the selection of appropriate ablation conditions. An organic pn junction is successfully constructed by the change of ablation conditions during ELA. Furthermore, ELA of PTCDA at 248 nm in iodine vapor leads to formation of tetraiodoallene in the film.

  13. An open label pilot study of supraerythemogenic excimer laser in combination with clobetasol spray and calcitriol ointment for the treatment of generalized plaque psoriasis.

    PubMed

    Levin, Ethan; Nguyen, Catherine M; Danesh, Melissa J; Beroukhim, Kourosh; Leon, Argentina; Koo, John

    2016-01-01

    A common therapeutic modality for psoriasis includes the combination of phototherapy with topical treatments. The recent development of targeted phototherapy with the excimer laser and spray formulations for topical treatments has increased the efficacy and convenience of these combinational therapies. Herein, we aim to assess the efficacy of a novel combination of therapies using the 308 nm excimer laser, clobetasol propionate spray and calcitriol ointment for the treatment of moderate to severe generalized psoriasis. In this 12-week study, patients with moderate to severe psoriasis received twice weekly treatments with a 308-nm excimer laser combined with clobetasol proprionate twice daily for a month followed by calcitriol ointment twice daily for the next month. Of the 30 patients enrolled, 83% of patients (25/30) achieved PASI-75 [65-94%, 95% confidence interval (CI)] at week 12. For PGA, there was an estimated decrease of 3.6 points (3.1-4.1, 95% CI, p < 0.0005) by week 12. In conclusion, the combination of excimer laser with alternating clobetasol and calcitriol application has shown to be a promising combination of therapies for the treatment of moderate to severe generalized psoriasis. Further evaluation may be conducted with a larger study inclusive of control groups and head-to-head comparisons against topical steroid and UVB therapy as monotherapies.

  14. 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.

  15. 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…

  16. An excimer-based FAIMS detector for detection of ultra-low concentration of explosives

    NASA Astrophysics Data System (ADS)

    Chistyakov, Alexander A.; Kotkovskii, Gennadii E.; Sychev, Alexey V.; Perederiy, Anatoly N.; Budovich, V. L.; Budovich, D. V.

    2014-05-01

    A new method of explosives detection based on the field asymmetric ion mobility spectrometry (FAIMS) and ionization by an excimer emitter has been developed jointly with a portable detector. The excimer emitter differs from usual UVionizing lamps by mechanism of emitting, energy and spectral characteristics. The developed and applied Ar2-excimer emitter has the working volume of 1 cm3, consuming power 0.6 W, the energy of photons of about 10 eV (λ=126 nm), the FWHM radiation spectrum of 10 nm and emits more than 1016 photon per second that is two orders of magnitude higher than UV-lamp of the same working volume emits. This also exceeds by an order of magnitude the quantity of photons per second for 10-Hz solid state YAG:Nd3+ - laser of 1mJ pulse energy at λ=266 nm that is also used to ionize the analyte. The Ar2-excimer ionizes explosives by direct ionization mechanism and through ionization of organic impurities. The developed Ar2-excimer-based ion source does not require cooling due to low level discharge current of emitter and is able to work with no repair more than 10000 hrs. The developed excimer-based explosives detector can analyze both vapors and traces of explosives. The FAIMS spectra of the basic types of explosives like trinitrotoluene (TNT), cyclotrimethylenetrinitramine (RDX), dinitrotoluene (DNT), cyclotetramethylenetetranitramine (HMX), nitroglycerine (NG), pentaerythritol tetranitrate (PETN) under Ar2-excimer ionization are presented. The detection limit determined for TNT vapors equals 1x10-14 g/cm3, for TNT traces- 100 pg.

  17. Communication: Photodissociation of CH{sub 3}CHO at 308 nm: Observation of H-roaming, CH{sub 3}-roaming, and transition state pathways together along the ground state surface

    SciTech Connect

    Li, Hou-Kuan; Tsai, Po-Yu; Hung, Kai-Chan; Kasai, Toshio; Lin, King-Chuen

    2015-01-28

    Following photodissociation of acetaldehyde (CH{sub 3}CHO) at 308 nm, the CO(v = 1–4) fragment is acquired using time-resolved Fourier-transform infrared emission spectroscopy. The CO(v = 1) rotational distribution shows a bimodal feature; the low- and high-J components result from H-roaming around CH{sub 3}CO core and CH{sub 3}-roaming around CHO radical, respectively, in consistency with a recent assignment by Kable and co-workers (Lee et al., Chem. Sci. 5, 4633 (2014)). The H-roaming pathway disappears at the CO(v ≥ 2) states, because of insufficient available energy following bond-breaking of H + CH{sub 3}CO. By analyzing the CH{sub 4} emission spectrum, we obtained a bimodal vibrational distribution; the low-energy component is ascribed to the transition state (TS) pathway, consistent with prediction by quasiclassical trajectory calculations, while the high-energy component results from H- and CH{sub 3}-roamings. A branching fraction of H-roaming/CH{sub 3}-roaming/TS contribution is evaluated to be (8% ± 3%)/(68% ± 10%)/(25% ± 5%), in which the TS pathway was observed for the first time. The three pathways proceed concomitantly along the electronic ground state surface.

  18. 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.

  19. 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.

  20. [Theoretical and physical aspects of excimer laser trabeculotomy (ELT) ab interno with the AIDA laser with a wave length of 308 mm].

    PubMed

    Walker, R; Specht, H

    2002-05-01

    Ablation of tissue structures containing and surrounded by water differs from tissue ablation at a surface, not only theoretically, but also in terms of outcome. In contrast to the situation often observed with surface ablation, it is shown that the trabecular meshwork in the anterior chamber of the eye can be ablated cleanly and accurately with the 308 nm Excimer laser without causing collateral thermal damage. The reason for this is that in the trabecular meshwork, the ratio of radiation-absorbing tissue to water--which absorbs very little energy--is very small. A marked cooling effect thus results, which permits the development of only a very small amount of collateral thermal damage at the boundaries of the ablation zone.

  1. High-power gas-discharge excimer ArF, KrCl, KrF and XeCl lasers utilising two-component gas mixtures without a buffer gas

    SciTech Connect

    Razhev, A M; Kargapol'tsev, E S; Churkin, D S

    2016-03-31

    Results of an experimental study of the influence of a gas mixture (laser active medium) composition on an output energy and total efficiency of gas-discharge excimer lasers on ArF* (193 nm), KrCl* (222 nm), KrF* (248 nm) and XeCl* (308 nm) molecules operating without a buffer gas are presented. The optimal ratios of gas components (from the viewpoint of a maximum output energy) of an active medium are found, which provide an efficient operation of laser sources. It is experimentally confirmed that for gas-discharge excimer lasers on halogenides of inert gases the presence of a buffer gas in an active medium is not a necessary condition for efficient operation. For the first time, in two-component gas mixtures of repetitively pulsed gas-discharge excimer lasers on electron transitions of excimer molecules ArF*, KrCl*, KrF* and XeCl*, the pulsed energy of laser radiation obtained under pumping by a transverse volume electric discharge in a low-pressure gas mixture without a buffer gas reached up to 170 mJ and a high pulsed output power (of up to 24 MW) was obtained at a FWHM duration of the KrF-laser pulse of 7 ns. The maximal total efficiency obtained in the experiment with two-component gas mixtures of KrF and XeCl lasers was 0.8%. (lasers)

  2. High-power gas-discharge excimer ArF, KrCl, KrF and XeCl lasers utilising two-component gas mixtures without a buffer gas

    NASA Astrophysics Data System (ADS)

    Razhev, A. M.; Kargapol'tsev, E. S.; Churkin, D. S.

    2016-03-01

    Results of an experimental study of the influence of a gas mixture (laser active medium) composition on an output energy and total efficiency of gas-discharge excimer lasers on ArF* (193 nm), KrCl* (222 nm), KrF* (248 nm) and XeCl* (308 nm) molecules operating without a buffer gas are presented. The optimal ratios of gas components (from the viewpoint of a maximum output energy) of an active medium are found, which provide an efficient operation of laser sources. It is experimentally confirmed that for gas-discharge excimer lasers on halogenides of inert gases the presence of a buffer gas in an active medium is not a necessary condition for efficient operation. For the first time, in two-component gas mixtures of repetitively pulsed gas-discharge excimer lasers on electron transitions of excimer molecules ArF*, KrCl*, KrF* and XeCl*, the pulsed energy of laser radiation obtained under pumping by a transverse volume electric discharge in a low-pressure gas mixture without a buffer gas reached up to 170 mJ and a high pulsed output power (of up to 24 MW) was obtained at a FWHM duration of the KrF-laser pulse of 7 ns. The maximal total efficiency obtained in the experiment with two-component gas mixtures of KrF and XeCl lasers was 0.8%.

  3. Excimer ultraviolet sources for thin film deposition: a 15 year perspective

    NASA Astrophysics Data System (ADS)

    Boyd, Ian W.; Liaw, Irving I.

    2010-02-01

    High intensity intensity ultraviolet (UV) and vacuum ultraviolet (VUV) radiation provide a singular dominant narrow-band emission at various wavelengths(λ) between 108 - 351 nm. The use of dielectric-barrier discharges in its embodiment of an excimer lamp as a photon-source provides a novel method to induce surface modification. From its in relatively humble beginnings in ozone generation, the excimer lamp has found new applications in the field of low-temperature processing of surfaces. Herein, a 15 year perspective of work done at the Materials & Devices Group at University College London between 1992 and 2007 is presented. The excimer lamps' application to the modification of surfaces for materials processing include: photo-induced formation of high-κ dielectric thin films and more recently the UV-induced photo-doping of silicon substrates, amongst others. With its robust yet inexpensive setup and flexibility of geometric configurations, they are easily coupled in parallel resulting in the provision of high photon fluxes over large areas. These sources also have an incoherent and almost monochromatic selectivity for application to process chemical pathway specific tasks by simple variation of the discharge gas mixture. These sources are an interesting addition to and an alternative to lasers for scalable industrial applications and have potential for a myriad of applications across different fields.

  4. Vacuum barrier for excimer lasers

    DOEpatents

    Shurter, Roger P.

    1992-01-01

    A barrier for separating the vacuum area of a diode from the pressurized gas area of an excimer laser. The barrier is a composite material comprising layers of a metal such as copper, along with layers of polyimide, and a matrix of graphite fiber yarns impregnated with epoxy. The barrier is stronger than conventional foil barriers, and allows greater electron throughput.

  5. Vacuum barrier for excimer lasers

    DOEpatents

    Shurter, R.P.

    1992-09-15

    A barrier for separating the vacuum area of a diode from the pressurized gas area of an excimer laser. The barrier is a composite material comprising layers of a metal such as copper, along with layers of polyimide, and a matrix of graphite fiber yarns impregnated with epoxy. The barrier is stronger than conventional foil barriers, and allows greater electron throughput. 3 figs.

  6. Fine structure in krypton excimer

    SciTech Connect

    Hemici, M.; Saoudi, R.; Descroix, E.; Audouard, E.; Laporte, P. ); Spiegelmann, F. )

    1995-04-01

    By using laser reduced fluorescence techniques, molecular absorption from the first relaxed excited excimer states of krypton is obtained in the 960--990-nm wavelength range. Five bands are observed and analyzed by comparison with an [ital ab] [ital initio] calculated spectrum. The fine structure is thus evidenced.

  7. Irradiation planning for automated treatment of psoriasis with a high-power excimer laser

    NASA Astrophysics Data System (ADS)

    Klämpfl, Florian; Schmidt, Michael; Hagenah, Hinnerk; Görtler, Andreas; Wolfsgruber, Frank; Lampalzer, Ralf; Kaudewitz, Peter

    2006-02-01

    American and European statistics have shown that 1-2 per cent of the human population is affected by the skin disease psoriasis. Recent research reports promising treatment results when irradiating skin areas affected by psoriasis with high powered excimer lasers with a wavelength of 308 nm. In order to apply the necessary high energy dose without hurting healthy parts of the skin new approaches regarding the system technology must be considered. The aim of the current research project is the development of a sensor-based, automated laser treatment system for psoriasis. In this paper we present the algorithms used to cope with the diffculties of irradiating irregularly shaped areas on curved surfaces with a predefined energy level using a pulsed laser. Patients prefer the treatment to take as little time as possible. This also helps to reduce costs. Thus the distribution of laser pulses on the surface to achieve the given energy level on every point of the surface has to be calculated within a limited time frame. The remainder of the paper will describe in detail an efficient method to plan and optimize the laser pulse distribution. Towards the end, some first results will be presented.

  8. 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

  9. 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 ( ...

  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. 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.

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

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 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 fog.... 108. Auxiliary driving lamps and/or front fog lamps may not be used to satisfy the requirements...

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

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 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 fog.... 108. Auxiliary driving lamps and/or front fog lamps may not be used to satisfy the requirements...

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 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 fog.... 108. Auxiliary driving lamps and/or front fog lamps may not be used to satisfy the requirements...

  15. Characterization of polyperinaphthalenic organic semiconductor thin films prepared by excimer laser ablation and application to anode electrodes for ultrathin rechargeable Li ion batteries

    NASA Astrophysics Data System (ADS)

    Nishio, Satoru; Tamura, Kazuyuki; Tsujine, Yukari; Fukao, Tomoko; Murata, Jun; Nakano, Masyoshi; Matsuzaki, Akiyoshi; Sato, Hiroyasu; Ando, Nobuo; Hato, Yukinori

    2001-06-01

    Polyperinaphthlenic organic semiconductor (PPNOS) films with polyperinaphthalene (PPN) structure for anode electrodes for ultra thin rechargeable Li ion batteries are prepared on temperature-controlled substrates by excimer laser ablation (ELA) of 3, 4, 9, 10-perylenetetracarboxylic dianhydride (PTCDA) or mixture target of PTCDA with a few metal powder (PTCDA/M) using a 308 nm (XeCl) pulsed excimer laser beam. It is demonstrated that ELA of PTCDA at a fluence of less than 0.5 Jcm-2pulse-1 enables us to obtain PPNOS on a substrate at 300 degree(s)C. It is found that ELA of PTCDA/Co at a fluence of more than 1.0 Jcm-4pulse-1 leads to produce effectively fragments without anhydride groups of PTCDA. FT-IR and Raman spectroscopies reveal that ELA of PTCDA/Co enables us to obtain better-defined PPN films with electric conductivity of approximately 1x10-1Scm-1 on a substrate at 300 degree(s)C. Electrochemical doping characteristics of lithium ion into the films obtained by ELA are performed to verify the lithium doping mechanism by in situ Raman spectroscopy. Furthermore a trial piece of thin lithium ion rechargeable battery with the films is fabricated to appraise performance of the films as anode thin electrodes for ultra thin rechargeable lithium ion batteries.

  16. Excimer laser in arthroscopic surgery

    NASA Astrophysics Data System (ADS)

    Koort, Hans J.

    1991-05-01

    The development of efficient high-power lasersystems for use in surgery, especially in arthroscopic fields, leads to a new push for all endoscopic techniques. Both techniques, laser and endoscope, complete each other in an ideal way and allow applications which could not be reached with conventional techniques. One of the newer laser types is the excimer laser, which will be a good choice for surface treatment because of its very considerate interaction with tissue. One example is the ablation or smoothing of articular cartilage and meniscal shaving in orthopaedics. On the other hand, the power of this laser system is high enough to cut tissue, for instance in the lateral release, and offers therefore an alternative to the mechanical and electrical instruments. All lasers can only work fine with effective delivery systems. Sometimes there is only a single fiber, which becomes very stiff at diameters of more than 800 micrometers . This fiber often allows only the tangential treatment of tissue, most of the laser power is lost in the background. New fiber systems with many, sometimes hundreds of very thin single fibers, could offer a solution. Special handpieces and fibersystems offer distinct advantages in small joint arthroscopy, especially those for use with excimer lasers will be discussed.

  17. 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.

  18. A repetitively pulsed xenon chloride excimer laser with all ferrite magnetic cores (AFMC) based all solid state exciter

    NASA Astrophysics Data System (ADS)

    Benerji, N. S.; Varshnay, N. K.; Ghodke, D. V.; Singh, A.

    2016-10-01

    Performance of repetitively pulsed xenon chloride excimer laser (λ~308 nm) with solid state pulser consisting of magnetic pulse compression circuit (MPC) using all ferrite magnetic cores (AFMC) is reported. Laser system suitable for 100 Hz operation with inbuilt pre-ionizer, compact gas circulation and cooling has been developed and presented. In this configuration, high voltage pulses of ~8 μs duration are compressed to ~100 ns by magnetic pulse compression circuit with overall compression factor of ~80. Pulse energy of ~18 J stored in the primary capacitor is transferred to the laser head with an efficiency of ~85% compared to ~70% that is normally achieved in such configurations using annealed met-glass core. This is a significant improvement of about 21%. Maximum output laser pulse energy of ~100 mJ was achieved at repetition rate of 100 Hz with a typical pulse to pulse energy stability of ±5% and laser pulse energy of 150 mJ was generated at low rep-rate of ~40 Hz. This exciter uses a low current and low voltage solid state switch (SCR) that replaces high voltage and high current switch i. e, thyratron completely. The use of solid state exciter in turn reduces electromagnetic interference (EMI) effects particularly in excimer lasers where high EMI is present due to high di/dt. The laser is focused on a thin copper sheet for generation of micro-hole and the SEM image of the generated micro hole shows the energy stability of the laser at high repetition rate operation. Nearly homogeneous, regular and well developed xenon chloride (XeCl) laser beam spot was achieved using the laser.

  19. Investigation into the interaction of a XeCl excimer laser with hard tissue

    NASA Astrophysics Data System (ADS)

    Murray, Andrea K.; Dickinson, Mark R.

    2000-06-01

    An investigation into the interaction of a fiber deliverable, long pulse, xenon chloride (308 nm) excimer laser with hard biotissue has been carried out. The laser produces pulses of 200+ ns as opposed to around 10 - 20 ns for most of the previously reported data. The threshold of ablation and the maximum ablation depth (AD) in human molar dentine were found to be 0.30 +/- 0.05 J/cm2 and 1.57 +/- 0.04 micrometer/pulse respectively. The threshold for enamel was found to be above the achievable fluence with the available optics. The ablation process was investigated as a function of fluence (approximately 0.1 - 6 J/cm2), pulse repetition rate (PRR) (5 - 25 Hz) and number of pulses (500 - 4000). Each variable was altered independently of the other two. At a constant number of pulses, ablation depth per pulse was found to increase linearly as a function of fluence, up to a saturation fluence of approximately 4 J/cm2. Variation of the PRR alone was found to affect both the ablation threshold and the AD. For constant fluence and PRR, AD decreases non- linearly with an increasing number of pulses. This could be because at high pulse numbers the craters are deep, the walls of the crater absorb more energy and as it is increasingly difficult for the debris to escape, shielding of the tissue occurs. Shielding may also be due to absorption in a luminescent plume. At high fluence and PRR, sharp holes were formed in the dentine although charring was sometimes found around the edges. High PRR also induced considerable mechanical damage.

  20. Semiconductor processing with excimer lasers

    SciTech Connect

    Young, R.T.; Narayan, J.; Christie, W.H.; van der Leeden, G.A.; Rothe, D.E.; Cheng, L.J.

    1983-01-01

    The advantages of pulsed excimer lasers for semiconductor processing are reviewed. Extensive comparisons of the quality of annealing of ion-implanted Si obtained with XeCl and ruby lasers have been made. The results indicate that irrespective of the large differences in the optical properties of Si at uv and visible wavelengths, the efficiency of usage of the incident energy for annealing is comparable for the two lasers. However, because of the excellent optical beam quality, the XeCl laser can provide superior control of the surface melting and the resulting junction depth. Furthermore, the concentrations of electrically active point defects in the XeCl laser annealed region are 2 to 3 orders of magnitude lower than that obtained from ruby or Nd:YAG lasers. All these results seem to suggest that XeCl lasers should be suitable for fabricating not only solar cells but also the more advanced device structures required for VLSI or VHSIC applications.

  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. 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.

  3. Turning on LAMP

    ScienceCinema

    Bostedt, Christoph

    2016-07-12

    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.

  4. 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.

  5. Rapid flash lamp

    DOEpatents

    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. Single photon ionization (SPI) via incoherent VUV-excimer light: robust and compact time-of-flight mass spectrometer for on-line, real-time process gas analysis.

    PubMed

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

    2002-08-01

    Fast on-line detection of organic compounds from complex mixtures, such as industrial process gas streams, require selective and sensitive analytical methods. One feasible approach for this purpose is the use of mass spectrometry (MS) with a selective and soft (fragment-free) ionization technique, such as chemical ionization (CI) or photo ionization (PI). Single photon ionization (SPI) with vacuum ultraviolet (VUV) light is a particularly sof tionization technique, well-suited for detection of both aromatic and aliphatic species. Problematic, however, is the generation of the VUV light. In general, the vacuum ultraviolet (VUV) light sources for SPI-MS are based either on lasers (e.g., 118-nm radiation generated by frequency-tripling of the third harmonic of a Nd:YAG laser) or on conventional VUV lamps, such as deuterium lamps. Althoughthe laser-based techniques are very sophisticated and expensive, the conventional lamps have serious drawbacks regarding their optical parameters, such as low-output power, low spectral power density, and broad emission bands. In this work, a novel excimer VUV light source, in which an electron beam is used to form rare gas excimer species, is used. The excimer VUV light sourceproduces brilliant and intense VUV light. The novel VUV light source was coupled to a compact and mobile time-of-flight mass spectrometer (TOFMS). A special interface design, including optical (VUV optics) as well as electronic measures (e.g., pulsed ion extraction) was realized. The use of the excimer VUV lamp for SPI will allow the realization of very compact, rugged, and sensitive SPI-TOFMS devices, which preferably will be adapted for process analytical application or monitoring issues (e.g., chemical warfare detection). The excimer VUV-lamp technology delivers VUV light with a good beam quality and high-output power at low costs. Furthermore, it allows changing the emitted wavelength as well as the bandwidth of the excimer VUV lamp in t he 100-200-nm region

  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. Effect of monochromatic excimer light on palmoplantar pustulosis: a clinical study performed in a private clinic by a dermatological specialist.

    PubMed

    Fumimori, Takeaki; Tsuruta, Daisuke; Kawakami, Tamihiro; Ohata, Chika; Furumura, Minao; Hashimoto, Takashi

    2013-12-01

    Palmoplantar pustulosis (PPP) is currently treated with various modalities, including excimer light, a form of ultraviolet lamp. This study reports effect of excimer light treatment in 34 Japanese PPP patients treated at a private clinic by one doctor, who was certified as a dermatological specialist by the Japanese Dermatological Association. The statistical analyses were performed upon a collaborative basis with faculties in universities. Disease response scores were determined by response to excimer light treatment. Scores of 1, 2, 3 or 4 were assigned to patients whose palmoplantar pustular psoriasis area and severity index (PPPASI) decreased to 25% or less, 25.1-50%, 50.1-75% or more than 75.1% of pretreatment PPPASI, respectively. In this study, 44.1% PPP cases had scores of 1 or 2, and considered good responders to excimer light treatment. There were no statistical differences between males and females, and between older (≥40 years) and younger groups (≤39 years) in terms of disease response score. Disease duration did not show any significant difference among these scores. Treatment times, total amount of ultraviolet and total treatment duration showed significant differences between score 1 and score 4 groups (P = 0.0164, =0.0137 and =0.0267, respectively). Particular interest was paid to smoking habits. Smoking in male patients was significantly higher than that in female patients (P = 0.0169). There was no statistical difference between smokers and non-smokers in terms of response to excimer light. In conclusion, this study suggested that excimer light is useful for both initial regimen and suppression of exacerbation in treatments of PPP.

  10. 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.

  11. 49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of the required headlamps. Auxiliary driving lamps shall meet SAE Standard J581 Auxiliary Upper Beam Lamps, July 2004, and front fog lamps shall meet SAE Standard J583 Front Fog Lamp, August 2004. (See... specifications in FMVSS No. 108 (49 CFR 571.108), SAE J581, and SAE J583, respectively. [70 FR 48046, Aug....

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of the required headlamps. Auxiliary driving lamps shall meet SAE Standard J581 Auxiliary Upper Beam Lamps, July 2004, and front fog lamps shall meet SAE Standard J583 Front Fog Lamp, August 2004. (See... specifications in FMVSS No. 108 (49 CFR 571.108), SAE J581, and SAE J583, respectively....

  13. Effect of excimer laser on microbiological organisms

    SciTech Connect

    Keates, R.H.; Drago, P.C.; Rothchild, E.J.

    1988-10-01

    The effect of radiation emitted from an excimer laser filled with argon fluoride gas at 193 nm on Serratia marcescens, Pseudomonas aeruginosa, Staphylococcus aureus, streptococcus faecalis, Hemophilus influenzae, Candida albicans, and Aspergillus niger (collectively labeled the microorganisms) was examined. Colonies were subjected to a variable number of radiation pulses from the excimer laser applied after a 36-hour period of incubation at 37 degrees C, at which time the colonies were fully grown and showed no viability. The lack of viability was confirmed with a subculture from each area that received radiation; all subcultures were negative. The characteristics of the radiation paralleled those used by Serdavic, Darrell, Krueger, et al in 1985. This radiation treatment is believed to be within a therapeutic range, which suggests that the excimer laser, pending further investigation, may be useful in the treatment of corneal infections.

  14. Developments in polymerization lamps.

    PubMed

    Jiménez-Planas, Amparo; Martín, Juan; Abalos, Camilo; Llamas, Rafael

    2008-02-01

    Polymerization shrinkage of composite resins and the consequent stress generated at the composite-tooth interface continue to pose a serious clinical challenge. The development of high-intensity halogen lamps and the advent of curing units providing higher energy performance, such as laser lamps, plasma arc units, and, most recently, light-emitting diode (LED) curing units, have revolutionized polymerization lamp use and brought major changes in light-application techniques. A comprehensive review of the literature yielded the following conclusions: (1) the most reliable curing unit for any type of composite resin is the high-density halogen lamp, fitted with a programming device to enable both pulse-delay and soft-start techniques; (2) if any other type of curing unit is used, information must be available on the compatibility of the unit with the composite materials to be used; (3) polymerization lamp manufacturers need to focus on the ongoing development of LED technology; (4) further research is required to identify the most reliable light-application techniques.

  15. Fluorescence Spectra Of Corneal Tissue Under Excimer Laser Irradiation

    NASA Astrophysics Data System (ADS)

    Loree, Thomas R.; Johnson, Tamara M.; Birmingham, Brian S.; McCord, Roy C.

    1988-06-01

    The corneas of pigs' eyes were irradiated with ablative levels of 193, 248, and 308 nm and the spectra of the produced light recorded. In all cases there was an appreciable amount of uv light produced in the 300-400 nm band. The 193 nm irradiation exhibited a threshold at 0.5 J/cm2; markedly different spectra were produced below and above that threshold.

  16. Profile characteristics of excimer laser micromachined features

    NASA Astrophysics Data System (ADS)

    Tabat, Martin D.; O'Keeffe, Terence R.; Ho, Wen

    1993-04-01

    In our work with excimer lasers, we observe a complex depth profile in processed blind holes that is energy, material, and process independent. This feature occurs when processing ceramics, polyimide, semiconductors, and metals. Further it occurs under different optical configurations. An understanding of this phenomena is essential when micron-precision features are required. We present our findings and explore explanations.

  17. Slit-lamp exam (image)

    MedlinePlus

    A slit-lamp, which is a specialized magnifying microscope, is used to examine the structures of the eye (including the cornea, iris, vitreous, and retina). The slit-lamp is used to examine, treat (with a laser), ...

  18. Luminescence characteristics of Xe{sub 2}Cl excimer molecules under pumping the dense Xe-CCl{sub 4} gas mixtures with a pulsed electron beam

    SciTech Connect

    Mis'kevich, A I; Jinbo, Guo

    2013-05-31

    Temporal and spectral characteristics of the luminescence of dense Xe-CCl{sub 4} gas mixtures of different composition, excited by a 5-ns pulsed electron beam, were measured. The energy of the electrons amounted to 150 keV and the electron beam current pulse amplitude was 5 A. The gas mixtures were used containing Xe (38-700 Torr) and CCl{sub 4} (0.03-0.3 Torr). The studies were performed within the wavelength range 200-1200 nm using a MAYA-2000Pro diffraction grating spectrometer and a RIGOL DS 5022 ME fast digital oscilloscope. The luminescence lifetimes of the excimer molecules XeCl* (band with {lambda}{sub max} = 308 nm) and Xe{sub 2}Cl* (band with {lambda}{sub max} = 486 nm) were measured, as well as the constants of quenching by the components of the gas mixture for Xe{sub 2}Cl* molecules. A model of plasma-chemical processes for dense Xe-CCl{sub 4} gas mixtures with a very low content of the CCl{sub 4} donor is proposed. It is shown that in such 'poor' mixtures Xe{sub 2}Cl* molecules are mainly produced as a result of recombination of the Xe{sub 2}{sup +} and Cl{sup -} ions. (active media)

  19. 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

  20. Dimming of metal halide lamps

    NASA Astrophysics Data System (ADS)

    Schurer, Kees

    1994-03-01

    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.

  1. 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.

  2. Concentration, temperature, and density in a hydrogen-air flame by excimer-induced Raman scattering

    NASA Technical Reports Server (NTRS)

    Wehrmeyer, Joseph A.; Bowling, John M.; Pitz, Robert W.

    1988-01-01

    Single-pulse, vibrational Raman scattering (VRS) is an attractive laser diagnostic for the study of supersonic hydrogen-air combustion. The VRS technique gives a complete thermodynamic description of the gas mixture at a point in the reacting flow. Single-pulse, vibrational Raman scattering can simultaneously provide independent measurements of density, temperature, and concentration of each major species (H2, H2O, O2 and N2) in a hydrogen/air turbulent combustor. Also the pressure can be calculated using the ideal gas law. However, single-pulse VRS systems in current use for measurement of turbulent combustion have a number of shortcomings when applied to supersonic flows: (1) slow repetition rate (1 to 5 Hz), (2) poor spatial resolution (0.5x0.3x0.3 cu mm), and (3) marginal time resolution. Most of these shortcomings are due to the use of visible wavelength flash-lamp pumped dye lasers. The advent of UV excimer laser allows the possibility of dramatic improvements in the single-pulse, vibrational Raman scattering. The excimer based VRS probe will greatly improve repetition rate (100 to 500 Hz), spatial resolution (0.1x0.1x0.1 cu mm) and time resolution (30ns). These improvements result from the lower divergence of the UV excimer, higher repetition rate, and the increased Raman cross-sections (15 to 20 times higher) at ultra-violet (UV) wavelengths. With this increased capability, single-pulse vibrational Raman scattering promises to be an ideal non-intrusive probe for the study of hypersonic propulsion flows.

  3. Compact fluorescent lamps, LED lamps and harmonic distortion

    NASA Astrophysics Data System (ADS)

    Franco, A. M. R.; Debatin, R. M.; Cotia, F. C. G.; Silva, M. V. M.; Ribeiro, R. S.; Zampilis, R. R. N.

    2015-01-01

    The aim of this paper is to evaluate the harmonic distortion in the current waveform of Compact Fluorescent Lamps (CFL) and Lamps Lighting Emitting Diode (LED). For this, we analysed the power factor, voltage waveform, current waveform, total harmonic distortion (THD) and active power consumed.

  4. 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.

  5. Human excimer laser corneal surgery: preliminary report.

    PubMed Central

    L'Esperance, F A; Taylor, D M; Del Pero, R A; Roberts, A; Gigstad, J; Stokes, M T; Warner, J W; Telfair, W B; Martin, C A; Yoder, P R

    1988-01-01

    The first human trial utilizing the argon fluoride excimer laser at 193 nm to produce a superficial keratectomy in ten human eyes has been described with the histopathological evaluation of four eyes and the longer gross appearance of six eyes at intervals extending to 10 months post-excimer laser treatment. The process of laser superficial keratectomy has proved to be one of the promising areas of surgical intervention for reconstructive or refractive keratoplasty in the future. Intensive investigations need to be undertaken on the corneal wound healing process following laser ablation as well as the nature, and long-term stability of the corneal excisions or induced refractive corrections. It is essential that the optimal laser parameters be established for the various refractive corrections and other corneal surgical techniques, and that pathophysiologic and histopathologic changes that have been induced by the excimer laser-corneal tissue interaction in animals and humans be critically and extensively analyzed. Images FIGURE 1 FIGURE 19 A FIGURE 19 B FIGURE 20 A FIGURE 20 B FIGURE 21 A FIGURE 21 B FIGURE 22 A FIGURE 22 B FIGURE 23 FIGURE 24 FIGURE 25 FIGURE 26 FIGURE 27 FIGURE 28 FIGURE 29 A FIGURE 29 B FIGURE 29 C FIGURE 29 D FIGURE 30 A FIGURE 30 B FIGURE 31 A FIGURE 31 B FIGURE 32 FIGURE 33 FIGURE 34 FIGURE 35 FIGURE 36 FIGURE 37 A FIGURE 37 B FIGURE 37 C FIGURE 38 A FIGURE 38 B FIGURE 39 A FIGURE 39 B FIGURE 39 C FIGURE 40 A FIGURE 40 B PMID:2979049

  6. 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.

  7. Quantum dot intermixing using excimer laser irradiation

    SciTech Connect

    Djie, H. S.; Ooi, B. S; Gunawan, O.

    2006-08-21

    The authors report a spatial control of the band gap in InGaAs/GaAs quantum dots (QDs) using the combined effects of pulsed excimer laser irradiation and impurity-free dielectric cap induced intermixing technique. A large band gap shift of up to 180 meV has been obtained under laser irradiation of 480 mJ/cm{sup 2} and 150 pulses to the SiO{sub 2} capped shallow QD structure, while the nonirradiated SiO{sub 2} and Si{sub x}N{sub y} capped QDs only exhibit band gap shifts of 18 and 91 meV, respectively.

  8. Excimer laser surface processing of titanium

    SciTech Connect

    Jervis, T.R.; Hubbard, K.M.; Zocco, T.G.; Foster, L.; Nastasi, M.; Tesmer, J.R.

    1993-05-01

    We have examined the effect of laser surface processing of Ti alloys using pulsed excimer laser light at 248 nm. Thermal transformations of the surface are accomplished by heating the surface and rapid cooling. Alloying and formation of compounds can be obtained by melting and mixing surface layers into the material and by gas alloying. Multiple melting-resolidification cycles result in the inter-diffusion of surface layers in the liquid state and the diffusion of gas species into the material. The effect of alloying from both solid and gas sources and the effects of thermal transformations on the microstructure and surface hardness properties of these alloys will be examined.

  9. Excimer laser surface processing of titanium

    SciTech Connect

    Jervis, T.R.; Hubbard, K.M.; Zocco, T.G.; Foster, L.; Nastasi, M.; Tesmer, J.R.

    1993-01-01

    We have examined the effect of laser surface processing of Ti alloys using pulsed excimer laser light at 248 nm. Thermal transformations of the surface are accomplished by heating the surface and rapid cooling. Alloying and formation of compounds can be obtained by melting and mixing surface layers into the material and by gas alloying. Multiple melting-resolidification cycles result in the inter-diffusion of surface layers in the liquid state and the diffusion of gas species into the material. The effect of alloying from both solid and gas sources and the effects of thermal transformations on the microstructure and surface hardness properties of these alloys will be examined.

  10. Laser desorption lamp ionization source for ion trap mass spectrometry.

    PubMed

    Wu, Qinghao; Zare, Richard N

    2015-01-01

    A two-step laser desorption lamp ionization source coupled to an ion trap mass spectrometer (LDLI-ITMS) has been constructed and characterized. The pulsed infrared (IR) output of an Nd:YAG laser (1064 nm) is directed to a target inside a chamber evacuated to ~15 Pa causing desorption of molecules from the target's surface. The desorbed molecules are ionized by a vacuum ultraviolet (VUV) lamp (filled with xenon, major wavelength at 148 nm). The resulting ions are stored and detected in a three-dimensional quadrupole ion trap modified from a Finnigan Mat LCQ mass spectrometer operated at a pressure of ≥ 0.004 Pa. The limit of detection for desorbed coronene molecules is 1.5 pmol, which is about two orders of magnitude more sensitive than laser desorption laser ionization mass spectrometry using a fluorine excimer laser (157 nm) as the ionization source. The mass spectrum of four standard aromatic compounds (pyrene, coronene, rubrene and 1,4,8,11,15,18,22,25-octabutoxy-29H,31H-phthalocyanine (OPC)) shows that parent ions dominate. By increasing the infrared laser power, this instrument is capable of detecting inorganic compounds.

  11. Excimer laser irradiation of metal surfaces

    NASA Astrophysics Data System (ADS)

    Kinsman, Grant

    In this work a new method of enhancing CO2 laser processing by modifying the radiative properties of a metal surface is studied. In this procedure, an excimer laser (XeCl) or KrF) exposes the metal surface to overlapping pulses of high intensity, 10(exp 8) - 10(exp 9) W cm(exp -2), and short pulse duration, 30 nsec FWHM (Full Width Half Maximum), to promote structural and chemical change. The major processing effect at these intensities is the production of a surface plasma which can lead to the formation of a laser supported detonation wave (LSD wave). This shock wave can interact with the thin molten layer on the metal surface influencing to a varying degree surface oxidation and roughness features. The possibility of the expulsion, oxidation and redeposition of molten droplets, leading to the formation of micron thick oxide layers, is related to bulk metal properties and the incident laser intensity. A correlation is found between the expulsion of molten droplets and a Reynolds number, showing the interaction is turbulent. The permanent effects of these interactions on metal surfaces are observed through scanning electron microscopy (SEM), transient calorimetric measurements and Fourier transform infrared (FTIR) spectroscopy. Observed surface textures are related to the scanning procedures used to irradiate the metal surface. Fundamental radiative properties of a metal surface, the total hemispherical emissivity, the near-normal spectral absorptivity, and others are examined in this study as they are affected by excimer laser radiation. It is determined that for heavily exposed Al surface, alpha' (10.6 microns) can be increased to values close to unity. Data relating to material removal rates and chemical surface modification for excimer laser radiation is also discussed. The resultant reduction in the near-normal reflectivity solves the fundamental problem of coupling laser radiation into highly reflective and conductive metals such as copper and aluminum. The

  12. 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.

  13. 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.

  14. Excimer laser annealing for low-voltage power MOSFET

    NASA Astrophysics Data System (ADS)

    Chen, Yi; Okada, Tatsuya; Noguchi, Takashi; Mazzamuto, Fulvio; Huet, Karim

    2016-08-01

    Excimer laser annealing of lumped beam was performed to form the P-base junction for high-performance low-voltage-power MOSFET. An equivalent shallow-junction structure for the P-base junction with a uniform impurity distribution is realized by adopting excimer laser annealing (ELA). The impurity distribution in the P-base junction can be controlled precisely by the irradiated pulse energy density and the number of shots of excimer laser. High impurity activation for the shallow junction has been confirmed in the melted phase. The application of the laser annealing technology in the fabrication process of a practical low-voltage trench gate MOSFET was also examined.

  15. 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...

  16. 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...

  17. Permanent excimer superstructures by supramolecular networking of metal quantum clusters

    NASA Astrophysics Data System (ADS)

    Santiago-Gonzalez, Beatriz; Monguzzi, Angelo; Azpiroz, Jon Mikel; Prato, Mirko; Erratico, Silvia; Campione, Marcello; Lorenzi, Roberto; Pedrini, Jacopo; Santambrogio, Carlo; Torrente, Yvan; De Angelis, Filippo; Meinardi, Francesco; Brovelli, Sergio

    2016-08-01

    Excimers are evanescent quasi-particles that typically form during collisional intermolecular interactions and exist exclusively for their excited-state lifetime. We exploited the distinctive structure of metal quantum clusters to fabricate permanent excimer-like colloidal superstructures made of ground-state noninteracting gold cores, held together by a network of hydrogen bonds between their capping ligands. This previously unknown aggregation state of matter, studied through spectroscopic experiments and ab initio calculations, conveys the photophysics of excimers into stable nanoparticles, which overcome the intrinsic limitation of excimers in single-particle applications—that is, their nearly zero formation probability in ultra-diluted solutions. In vitro experiments demonstrate the suitability of the superstructures as nonresonant intracellular probes and further reveal their ability to scavenge reactive oxygen species, which enhances their potential as anticytotoxic agents for biomedical applications.

  18. 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.

  19. The Excimer Laser: Its Impact on Science and Industry

    NASA Astrophysics Data System (ADS)

    Basting, Dirk

    2010-03-01

    After the laser was demonstrated in 1960, 15 years were required to develop a practical method for extending laser emission into the UV: the Excimer laser. This historical review will describe the challenges with the new medium and provide an insight into the technological achievements. In the transition from Science to Industry it will be shown how start-ups successfully commercialized laboratory prototypes. The pioneers in this rapidly expanding field will be identified and the influence of government-funded research as well as the role of venture capital will be discussed. In scientific applications, the fields of photochemistry and material research were particularly stimulated by the advent of a reliable UV light source. Numerous industrial applications and worldwide research in novel applications were fueled In the early and mid 80's by progress in excimer laser performance and technology. The discovery of ablative photocomposition of polymer materials by Srinivasan at IBM opened the door to a multitude of important excimer applications. Micromachining with extreme precision with an excimer laser enabled the success of the inkjet printer business. Biological materials such as the human cornea can also be ``machined'' at 193nm, as proposed in 1983 by Trokel and Srinivasan. This provided the foundation of a new medical technology and an industry relying on the excimer laser to perform refractive surgery to correct vision Today, by far the largest use of the excimer laser is in photolithography to manufacture semiconductor chips, an application discovered by Jain at IBM in the early 80's. Moore's law of shrinking the size of the structure to multiply the number of transistors on a chip could not have held true for so long without the deep UV excimer laser as a light source. The presentation will conclude with comments on the most recent applications and latest market trends.

  20. Excimer laser crystallization of hydrogenated amorphous silicon

    SciTech Connect

    Dai Yongbing; Xu Zhongyang; Wang Changan; Zhang Shaoqiang; An Chengwu; Li Xingjiao; Wan Xinheng; Ding Hui

    1996-12-31

    Hydrogenated amorphous silicon (a-Si:H) films have been crystallized by the irradiations of XeCl excimer laser. The crystallized films have been examined by scanning electron microscopy (SEM), x-ray diffraction (XRD) and conductivity measurements to clarify their morphologies, structure and electrical properties. The results show that a high conductive super thin layer is formed by a single pulse laser irradiation with the energy density of 75mJ/cm{sup 2}. The conductivity increases quickly at laser energy density threshold which decreases when the hydrogen in a-Si:H films is removed by pre-annealing. During crystallization process, oxygen atoms from the air ambient have been introduced into the films and such an introducing process is hindered by the hydrogen eruption. When the oxygen content is high enough, the carrier-transport mechanism includes thermionic emission (TE) and thermionic field emission (TFE) in the vicinity of room temperature, which is similar to semi-insulating polycrystalline silicon (SIPOS).

  1. Excimer laser surface modification: Process and properties

    SciTech Connect

    Jervis, T.R.; Nastasi, M.; Hirvonen, J.P.

    1992-12-01

    Surface modification can improve materials for structural, tribological, and corrosion applications. Excimer laser light has been shown to provide a rapid means of modifying surfaces through heat treating, surface zone refining, and mixing. Laser pulses at modest power levels can easily melt the surfaces of many materials. Mixing within the molten layer or with the gas ambient may occur, if thermodynamically allowed, followed by rapid solidification. The high temperatures allow the system to overcome kinetic barriers found in some ion mixing experiments. Alternatively, surface zone refinement may result from repeated melting-solidification cycles. Ultraviolet laser light couples energy efficiently to the surface of metallic and ceramic materials. The nature of the modification that follows depends on the properties of the surface and substrate materials. Alloying from both gas and predeposited layer sources has been observed in metals, semiconductors, and ceramics as has surface enrichment of Cr by zone refinement of stainless steel. Rapid solidification after melting often results in the formation of nonequilibrium phases, including amorphous materials. Improved surface properties, including tribology and corrosion resistance, are observed in these materials.

  2. Chemical-free cleaning using excimer lasers

    NASA Astrophysics Data System (ADS)

    Lizotte, Todd E.; O'Keeffe, Terence R.

    1996-04-01

    A critical requirement in many industrial processes is the cleaning of oils and grease, oxides, solvent residues, particles, thin films and other contaminants from surfaces. There is a particularly acute need in the electronics industry for cleaning semiconductor wafers and computer chips and in the metals industry for removing oxides and other contaminants. Cleaning traditionally is done by various wet chemical processes, almost all consuming large amounts of water and producing large amounts of hazardous wastes. To further complicate this, some of these cleaning agents and vast water consumption are undergoing stringent restrictions. The Radiance ProcessSM is a novel, patented Excimer Laser approach to dry surface cleaning. The process has removed particles from 80 microns to submicron sizes, paints, inks, oxides, fingerprints, hazes, parts of molecules and metallic ions in fingerprints. The process does not ablate, melt or damage the underlying surface. Micro-roughening on some Silicon and Gallium Arsenide is on the order of 1A or less. This paper will discuss the various applications with this process and the latest results from a beta wafer cleaning prototype test bed system that is being built under an EPA grant and joint partnership between Radiance Services Company, Neuman Micro Technologies, Inc. and the Microelectronics Research Laboratory.

  3. Excimer laser annealing for fabrication of low-cost solar cells

    NASA Technical Reports Server (NTRS)

    Greenwald, A. C.

    1984-01-01

    The goal was to determine if a pulsed excimer laser annealing (PELA) is cost effective compared to a baseline process. An excimer laser pulsed annealing apparatus was built. Three hundred solar cells were fabricated. An economic analysis was performed.

  4. Neutron detection by scintillation of noble-gas excimers

    NASA Astrophysics Data System (ADS)

    McComb, Jacob Collin

    Neutron detection is a technique essential to homeland security, nuclear reactor instrumentation, neutron diffraction science, oil-well logging, particle physics and radiation safety. The current shortage of helium-3, the neutron absorber used in most gas-filled proportional counters, has created a strong incentive to develop alternate methods of neutron detection. Excimer-based neutron detection (END) provides an alternative with many attractive properties. Like proportional counters, END relies on the conversion of a neutron into energetic charged particles, through an exothermic capture reaction with a neutron absorbing nucleus (10B, 6Li, 3He). As charged particles from these reactions lose energy in a surrounding gas, they cause electron excitation and ionization. Whereas most gas-filled detectors collect ionized charge to form a signal, END depends on the formation of diatomic noble-gas excimers (Ar*2, Kr*2,Xe* 2) . Upon decaying, excimers emit far-ultraviolet (FUV) photons, which may be collected by a photomultiplier tube or other photon detector. This phenomenon provides a means of neutron detection with a number of advantages over traditional methods. This thesis investigates excimer scintillation yield from the heavy noble gases following the boron-neutron capture reaction in 10B thin-film targets. Additionally, the thesis examines noble-gas excimer lifetimes with relationship to gas type and gas pressure. Experimental data were collected both at the National Institute of Standards and Technology (NIST) Center for Neutron Research, and on a newly developed neutron beamline at the Maryland University Training Reactor. The components of the experiment were calibrated at NIST and the University of Maryland, using FUV synchrotron radiation, neutron imaging, and foil activation techniques, among others. Computer modeling was employed to simulate charged-particle transport and excimer photon emission within the experimental apparatus. The observed excimer

  5. 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...

  6. 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.

  7. 49 CFR 234.221 - Lamp voltage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Lamp voltage. 234.221 Section 234.221 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., Inspection, and Testing Maintenance Standards § 234.221 Lamp voltage. The voltage at each lamp shall...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. Experimental study of 248nm excimer laser etching of alumina

    NASA Astrophysics Data System (ADS)

    Hu, Hongtao; Shao, Jingzhen; Wang, Xi; Fang, Xiaodong

    2016-10-01

    The 248 nm excimer laser etching characteristic of alumina ceramic and sapphire had been studied using different laser fluence and different number of pulses. And the interaction mechanism of 248 nm excimer laser with alumina ceramic and sapphire had been analyzed. The results showed that when the laser fluence was less than 8 J/cm2, the etching depth of alumina ceramic and sapphire were increased with the increase of laser fluence and number of pulses. At the high number pulses and high-energy, the surface of the sapphire had no obvious melting phenomenon, and the alumina ceramic appeared obvious melting phenomenon. The interaction mechanism of excimer laser with alumina ceramics and sapphire was mainly two-photon absorption. But because of the existence of impurities and defects, the coupling between the laser radiation and ceramic and sapphire was strong, and the thermal evaporation mechanism was also obvious.

  14. Predictive factors of restenosis following excimer laser coronary angioplasty

    NASA Astrophysics Data System (ADS)

    Geschwind, Herbert J.; Kvasnicka, Jan; Duport, George; Escojido, Henri; Lablanche, Jean M.

    1993-06-01

    Excimer laser coronary angioplasty has been shown to result in high acute success rate. However, long term follow up has shown significant restenosis. To evaluate the restenosis predictive factors, we analyzed data from patients treated by excimer laser angioplasty in four French clinical centers. A cohort of 166 patients, 140 men and 26 women with mean age of 58 +/- 11 years, was enrolled in the study. Total occlusions, tubular, ostial and calcified lesions, unsuccessful balloon dilatation and/or restenosis were considered as indications for laser angioplasty. Follow-up angiography six months after the procedure was achieved in 80 patients. In conclusion, excimer laser angioplasty is associated with a high initial success rate and an acceptable major complications rate. However the use of this method is limited by significant restenosis rate.

  15. Overview on the high power excimer laser technology

    NASA Astrophysics Data System (ADS)

    Liu, Jingru

    2013-05-01

    High power excimer laser has essential applications in the fields of high energy density physics, inertial fusion energy and industry owing to its advantages such as short wavelength, high gain, wide bandwidth, energy scalable and repetition operating ability. This overview is aimed at an introduction and evaluation of enormous endeavor of the international high power excimer laser community in the last 30 years. The main technologies of high power excimer laser are reviewed, which include the pumping source technology, angular multiplexing and pulse compressing, beam-smoothing and homogenous irradiation, high efficiency and repetitive operation et al. A high power XeCl laser system developed in NINT of China is described in detail.

  16. Batch patterning micro circuits and sensors with excimer laser machine

    NASA Astrophysics Data System (ADS)

    Yang, Ren; Pyka, Ralph; Kramer, Dennis; Mata, John; Souter, Matt; Thompson, Steven

    2008-02-01

    This paper will present the direct photo patterning of micro circuits and sensors with a XeCl excimer laser photo ablation system. The working principle and the ablation equipment for photo ablation of conductive thin film on polymer are described. Both large sheets and reel-to-reel webs can be ablated on this excimer laser photo ablation system. The ablation strategies and alignment strategies for the micro circuits and sensors are introduced. The test results show ablation results with high resolution, high throughput, high yield and cost-efficiency. This clearly shows that excimer laser photo ablation of the conductive materials on polymer substrates is a good choice for industrial mass product fabrication of low priced, disposable micro circuit and sensor devices.

  17. Pre-bonding technology based on excimer laser surface treatment

    NASA Astrophysics Data System (ADS)

    Rotel, M.; Zahavi, J.; Tamir, S.; Buchman, A.; Dodiuk, H.

    2000-02-01

    The application of ArF excimer laser for surface pre-treatment of polycarbonate, polyetherimide, polyaryl ether-ether-ketone (PEEK) composite, fiberglass, aluminum, copper and fused silica was investigated. Various substrates were tested with excimer laser irradiation using various parameters, such as: intensity, repetition rate, and number of pulses. The optimal laser treatment parameters were found for each material needed for achieving maximum adhesional strength of the corresponding bonded joints. Experimental results indicated that UV laser surface treatment improved significantly the adhesion strength compared to conventional treated substrates for all the materials tested. The improved adhesion was correlated with the roughening of the irradiated surface, chemical modification and removal of contamination.

  18. Excimer laser induced plasma for aluminum alloys surface carburizing

    NASA Astrophysics Data System (ADS)

    Fariaut, F.; Boulmer-Leborgne, C.; Le Menn, E.; Sauvage, T.; Andreazza-Vignolle, C.; Andreazza, P.; Langlade, C.

    2002-01-01

    Currently, while light alloys are useful for automotive industries, their weak wear behavior is a limiting factor. The excimer laser carburizing process reported here has been developed to enhance the mechanical and chemical properties of aluminum alloys. An excimer laser beam is focused onto the alloy surface in a cell containing 1 bar methane or/and propylene gas. A vapor plasma expands from the surface, the induced shock wave dissociates and ionizes the ambient gas. Carbon atoms diffuse into the plasma in contact with the irradiated surface. An aluminum carbide layer is created by carbon diffusion in the surface liquid layer during the recombination phase of the plasma.

  19. Three years of clinical experiences on excimer laser angioplasty

    NASA Astrophysics Data System (ADS)

    Viligiardi, Riccardo; Galiberti, Sandra; Pini, Roberto; Salimbeni, Renzo

    1992-08-01

    Our experience on excimer laser angioplasty in peripheral arteries is reported. During three years 34 patients were treated with improved techniques, following the evolution of the laser and of the delivery systems. Encouraging results in the laser stand alone technique allowed us to reduce the association with balloon dilatation to a limited number of cases.

  20. Excimer laser coronary angioplasty: clinical results and future directions

    NASA Astrophysics Data System (ADS)

    Bittl, John A.

    1993-06-01

    Despite four years of intensive clinical investigation, excimer laser coronary angioplasty has not been accepted by the interventional cardiology community as the intervention of choice for any lesion type. Although the preliminary analysis presented here shows that the new technology shows promise for the treatment of saphenous vein graft lesions, aorto-ostial lesions and other lesions, these lesion types account for only about 5 - 10% of cases currently targeted for angioplasty and can frequently be treated with other interventional methods. Broader use of excimer laser angioplasty requires convincing proof that the new technology has clear superiority over other interventional techniques for a wider range of lesion types. Furthermore, the mechanisms of vessel dissection, perforation and abrupt closure need further clarification. Thus, the major challenges for excimer laser angioplasty include: (1) randomized trials to document the superiority of excimer laser over balloon angioplasty; (2) improved catheter designs, including devices for eccentric lesions and total occlusions; and (3) a better understanding of laser-tissue interactions to reduce the unpredictability of unfavorable angiographic outcome.

  1. Advances in 193 nm excimer lasers for mass spectrometry applications

    NASA Astrophysics Data System (ADS)

    Delmdahl, Ralph; Esser, Hans-Gerd; Bonati, Guido

    2016-03-01

    Ongoing progress in mass analysis applications such as laser ablation inductively coupled mass spectrometry of solid samples and ultraviolet photoionization mediated sequencing of peptides and proteins is to a large extent driven by ultrashort wavelength excimer lasers at 193 nm. This paper will introduce the latest improvements achieved in the development of compact high repetition rate excimer lasers and elaborate on the impact on mass spectrometry instrumentation. Various performance and lifetime measurements obtained in a long-term endurance test over the course of 18 months will be shown and discussed in view of the laser source requirements of different mass spectrometry tasks. These sampling type applications are served by excimer lasers delivering pulsed 193 nm output of several mJ as well as fast repetition rates which are already approaching one Kilohertz. In order to open up the pathway from the laboratory to broader market industrial use, sufficient component lifetimes and long-term stable performance behavior have to be ensured. The obtained long-term results which will be presented are based on diverse 193 nm excimer laser tube improvements aiming at e.g. optimizing the gas flow dynamics and have extended the operational life the laser tube for the first time over several billion pulses even under high duty-cycle conditions.

  2. Temperature measurement on and inside lamps

    NASA Astrophysics Data System (ADS)

    Wallin, Bo

    1994-03-01

    The use of thermography within the lamp manufacturing industry can improve the quality of many types of lamps ranging from normal incandescent lamps to highly specialized lamps for sports arenas, airports or small lamps for cars. There is a strong demand for more light for the same energy input. Specialized lamps for all possible purposes are developed. But it also forces the lamp manufacturers to utilize the available materials to their extremes. The exact control of the temperatures inside or on the lamp shell has therefore become increasingly necessary as temperatures in lamps can be rather extreme. In plasma lamps for example, the plasma can have a temperature of 6000 C, the bulb around 700 C and the electrodes inside the bulb can have temperatures in excess of 2000 C. Thermographic methods have shown their applicability for a large number of measurement cases. Some of these methods and measurement cases are described. As these applications put very special demands on the measurement equipment, these demands are explained in more detail.

  3. K-Rb Laser Pump Lamp

    DTIC Science & Technology

    1975-11-01

    testing midway in the program prompted a decision to fabricate two silicide - coated niobium endcap lamps prior to completion of the first coating eval...envelope material was developed. Finally, encouraging preliminary results with a fused silicide protective coating suggest that a coated niobium endcap...this lamp. Encouraging results were obtained with a fused silicide oxidation protective coating for niobiun endcap lamps. The best life tes result on

  4. 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.

  5. 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.

  6. Slit lamp photography: The basics.

    PubMed

    Painter, Rosalyn

    2015-06-01

    This introductory paper is designed to explain the basics of slit lamp photography with the use of illustrations and sample images. The two primary methods of illumination are described with reference to positioning and magnification, as well as the use of background illumination. Filters and dye usage are described along with a brief explanation of associated imaging techniques. Further explanation of techniques will be looked at in subsequent articles, this paper aims to give an over view rather than an in-depth discussion of techniques.

  7. 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....40 Candelabra base incandescent lamps and intermediate base incandescent lamps. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to candelabra...

  8. 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....40 Candelabra base incandescent lamps and intermediate base incandescent lamps. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to candelabra...

  9. 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....40 Candelabra base incandescent lamps and intermediate base incandescent lamps. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to candelabra...

  10. 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.

  11. Spectrum characteristic study of sodium-ethane excimer pairs

    NASA Astrophysics Data System (ADS)

    Hu, Shu; Gai, Baodong; Wang, Pengyuan; Li, Hui; Tan, Yannan; Liu, Jinbo; Guo, Jingwei

    2017-01-01

    Excimer pumped sodium laser (XPNaL) can accurately achieve lasing at 589.16 nm without any complicated control system to reduce the wavelength error, so XPNaL will provide a novel technical system for sodium beacon laser. In this paper, we studied the Na-C2H6 system, which was an efficient excimer pair. We excited the Na-C2H6 system using a pulsed dye laser with wavelength of 553 nm, and measured lifetime of sodium D2 line based on the fluorescence spectra. Meanwhile, we have also detected strong amplified spontaneous emission (ASE) signal in Na-C2H6 system, through the experimental study, the Na-C2H6 system is considered to own the potential to be utilized in high power XPNaL.

  12. Triggering Excimer Lasers by Photoionization from Corona Discharges

    NASA Astrophysics Data System (ADS)

    Xiong, Zhongmin; Duffey, Thomas; Brown, Daniel; Kushner, Mark

    2009-10-01

    High repetition rate ArF (192 nm) excimer lasers are used for photolithography sources in microelectronics fabrication. In highly attaching gas mixtures, preionization is critical to obtaining stable, reproducible glow discharges. Photoionization from a separate corona discharge is one technique for preionization which triggers the subsequent electron avalanche between the main electrodes. Photoionization triggering of an ArF excimer laser sustained in multi-atmosphere Ne/Ar/F2/Xe gas mixtures has been investigated using a 2-dimensional plasma hydrodynamics model including radiation transport. Continuity equations for charged and neutral species, and Poisson's equation are solved coincident with the electron temperature with transport coefficients obtained from solutions of Boltzmann's equation. Photoionizing radiation is produced by a surface discharge which propagates along a corona-bar located adjacent to the discharge electrodes. The consequences of pulse power waveform, corona bar location, capacitance and gas mixture on uniformity, symmetry and gain of the avalanche discharge will be discussed.

  13. Excimer laser interaction with dentin of the human tooth

    NASA Technical Reports Server (NTRS)

    Hammond, Ernest C., Jr.; Gilliam, Ruth L.; Baker, George R.

    1989-01-01

    The use an excimer laser produced many unusual conical structures within the dentin of the inner part of the human tooth. By varying the frequency of the laser one can disperse the energy and cause more bleeding in laser surgery, but not destroy the cells associated with the incision. Therefore, the healing process will virtually be without scarring. Whereas, using the infrared laser the blood loss would be less, but the healing process would tend to be longer because cells are being destroyed due to the cauterization effect of the laser. The question is, are these structures produced as an interaction with the laser or are they an intrinsic part of the structure. The effects of the laser interaction upon dentin was studied, and in using electron microscopy the interaction of the excimer laser upon the tooth dentin and other various biological tissue is more clearly understood.

  14. 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...

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

    SciTech Connect

    Torres, C.

    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.

  16. Nebulae at keratoconus--the result after excimer laser removal.

    PubMed

    Fagerholm, P; Fitzsimmons, T; Ohman, L; Orndahl, M

    1993-12-01

    Ten patients underwent excimer laser ablation due to nebula formation at keratoconus. The nebulae interfered significantly with contact lens fit or wearing time. The mean follow-up time in these patients was 16.5 months. Following surgery all patients could be successfully fitted with a contact lens and thereby obtain good visual acuity. Furthermore, contact lens wearing time was 8 hours or more in all cases. In 2 patients the nebulae recurred but were successfully retreated.

  17. Automatic alignment of double optical paths in excimer laser amplifier

    NASA Astrophysics Data System (ADS)

    Wang, Dahui; Zhao, Xueqing; Hua, Hengqi; Zhang, Yongsheng; Hu, Yun; Yi, Aiping; Zhao, Jun

    2013-05-01

    A kind of beam automatic alignment method used for double paths amplification in the electron pumped excimer laser system is demonstrated. In this way, the beams from the amplifiers can be transferred along the designated direction and accordingly irradiate on the target with high stabilization and accuracy. However, owing to nonexistence of natural alignment references in excimer laser amplifiers, two cross-hairs structure is used to align the beams. Here, one crosshair put into the input beam is regarded as the near-field reference while the other put into output beam is regarded as the far-field reference. The two cross-hairs are transmitted onto Charge Coupled Devices (CCD) by image-relaying structures separately. The errors between intersection points of two cross-talk images and centroid coordinates of actual beam are recorded automatically and sent to closed loop feedback control mechanism. Negative feedback keeps running until preset accuracy is reached. On the basis of above-mentioned design, the alignment optical path is built and the software is compiled, whereafter the experiment of double paths automatic alignment in electron pumped excimer laser amplifier is carried through. Meanwhile, the related influencing factors and the alignment precision are analyzed. Experimental results indicate that the alignment system can achieve the aiming direction of automatic aligning beams in short time. The analysis shows that the accuracy of alignment system is 0.63μrad and the beam maximum restoration error is 13.75μm. Furthermore, the bigger distance between the two cross-hairs, the higher precision of the system is. Therefore, the automatic alignment system has been used in angular multiplexing excimer Main Oscillation Power Amplification (MOPA) system and can satisfy the requirement of beam alignment precision on the whole.

  18. Pulsed excimer laser processing for cost-effective solar cells

    NASA Technical Reports Server (NTRS)

    Wong, David C.

    1985-01-01

    The application of excimer laser in the fabrication of photovoltaic devices was investigated extensively. Processes included junction formation, laser assisted chemical vapor deposition metallization, and laser assisted chemical vapor deposition surface passivation. Results demonstrated that implementation of junction formation by laser annealing in production is feasible because of excellent control in junction depth and quality. Both metallization and surface passivation, however, were found impractical to be considered for manufacturing at this stage.

  19. Gain and Lasing in Nuclear Excited Excimer Laser Systems.

    DTIC Science & Technology

    1981-04-24

    sources. The most advantageous volumetric nuclear excitation source is UF If enriched UF could be used as a pump source, a self- critical NPL could be...3 lower laser state by nuclear excitation and gas heating or by quenching of the upper laser state by UF6 and other species. Most NPLs demonstrated...induced effects, the loss in power density may be more critical than any nuclear considerations.I * Direct nuclear pumping of XeF excimer lasers has been

  20. 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 Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp....

  1. 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 Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp....

  2. 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 Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp....

  3. 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 Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp....

  4. 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 Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp....

  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, 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....

  7. 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....

  8. 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....

  9. 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....

  10. 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)…

  11. Periodically pulsed excimer master oscillator-regenerative amplifier laser set

    NASA Astrophysics Data System (ADS)

    Ageyev, V. P.; Atezhev, V. V.; Bukreyev, V. S.; Vartapetov, S. K.; Zhukov, A. I.; Konov, V. I.; Savelyev, A. D.

    1987-06-01

    A periodically pulsed excimer laser set consisting of a master oscillator and a regenerative amplifier is proposed for improvement of laser beam characteristics, particularly decreasing divergence in the case of short pumping pulses and attendant high gain. Each active medium is pumped by electric discharge, both discharge circuits using magnetic switches with a common commutator so that the laser energy characteristics and the time separation between gain buildup in the two lasers can be simultaneously optimized. An experimental set was built with a Model 170 excimer laser as amplifier and a compact excimer laser as oscillator. Tests were performed with F2 + Kr + He mixtures lasing at lambda = 248, with and without injection. Emission pulses were produced at a repetition rate of 20 Hz and the beam divergence was measured through a lens with a focal length of 300 cm. The oscillator beam with a divergence of 600 microrad carried an energy of 700 microJ per pulse and was amplified to 35 mJ. The divergence of the amplified beam in the direction parallel to that of the discharge current was 140 microrad without injection and 80 microrad with injection. Divergence in the perpendicular direction was 90 microrad without and with injection.

  12. Excimer surface treatment to enhance bonding in coated steels

    NASA Astrophysics Data System (ADS)

    Mueller, Robert E.; Olfert, M.; Duley, Walter W.; North, T.; Hood, J.; Sakai, D.

    1996-04-01

    Zinc coated sheet steel in the form of temper rolled galvanize and galvanneal are used extensively in the automotive industry. Through a process of excimer laser surface treatment, we have succeeded in significantly enhancing the adhesion characteristics of these coated steels. The laser treatment is performed by scanning focused excimer laser radiation in a raster pattern over the surface to be bonded. Adhesion tests have been carried out in the form of T peel tests, using either a hot melt nylon resin or an epoxy as the adhesive. An increase in bond strength was observed over a substantial range of surface treatment conditions. The largest improvement observed was more than a factor of three greater than for untreated surfaces. With the improved surface condition, the bond strength became limited by the cohesive strength of the adhesive. The physical structure and chemical composition of the parent and excimer treated surfaces have been examined using scanning electron microscopy and X-ray photoelectron spectroscopy to determine the nature and extent of the changes caused by the surface treatment. The effects of the observed changes on the bonding performance will be discussed. Surfaces have been processed under an inert atmosphere to isolate the effects of physical surface modification and surface oxidation. An attempt will be made to correlate the surface changes with the bonding characteristics and thereby indicate which changes are most beneficial. The ultimate goal is to optimize the surface condition for bonding and maximize the process rate.

  13. Excimer emission from pulsed microhollow cathode discharges in xenon

    SciTech Connect

    Lee, B.-J.; Nam, S. H.; Rahaman, H.; Iberler, M.; Jacoby, J.; Frank, K.

    2013-12-15

    Direct current (dc) microhollow cathode discharge (MHCD) is an intense source for excimer radiation in vacuum ultraviolet at a wavelength of 172 nm in a high pressure xenon (Xe) gas. The concentration of precursors for the excimer formation, i.e., excited and ionized gas atoms, increases significantly by applying high voltage pulse onto the dc MHCD over the pulse duration range from 20 to 100 ns. The intensity of the excimer emission for the voltage pulse of 20 ns duration exceeds that of the emission intensity obtained from the same MHCD operated only in the dc mode, by one order of magnitude. In addition, the emission intensity increases by one order of magnitude over the pulse duration range from 20 to 100 ns. It can be assumed that the emission intensity of the MHCD source increases as long as the duration of the high voltage pulse is shorter than the electron relaxation time. For the high voltage pulse of 100 ns duration, the emission intensity has been found to be further enhanced by a factor of three when the gas pressure is increased from 200 to 800 mbar.

  14. Impacts of excimer laser annealing on Ge epilayer on Si

    NASA Astrophysics Data System (ADS)

    Huang, Zhiwei; Mao, Yichen; Yi, Xiaohui; Lin, Guangyang; Li, Cheng; Chen, Songyan; Huang, Wei; Wang, Jianyuan

    2017-02-01

    The impacts of excimer laser annealing on the crystallinity of Ge epilayers on Si substrate grown by low- and high-temperature two-step approach in an ultra-high vacuum chemical vapor deposition system were investigated. The samples were treated by excimer laser annealing (ELA) at various laser power densities with the temperature above the melting point of Ge, while below that of Si, resulting in effective reduction of point defects and dislocations in the Ge layer with smooth surface. The full-width at half-maximum (FWHM) of X-ray diffraction patterns of the low-temperature Ge epilayer decreases with the increase in laser power density, indicating the crystalline improvement and negligible effect of Ge-Si intermixing during ELA processes. The short laser pulse time and large cooling rate cause quick melting and recrystallization of Ge epilayer on Si in the non-thermal equilibrium process, rendering tensile strain in Ge epilayer as calculated quantitatively with thermal mismatch between Si and Ge. The FWHM of X-ray diffraction patterns is significantly reduced for the two-step grown samples after treated by a combination of ELA and conventional furnace thermal annealing, indicating that the crystalline of Ge epilayer is improved more effectively with pre- annealing by excimer laser.

  15. Assessment of the Suitability of Excimer Lasers in Treating Onychomycosis

    NASA Astrophysics Data System (ADS)

    Kymplová, Jaroslava; Jelínek, Miroslav; Urzová, Jana; Mikšovský, Jan; Dušek, Karel; Bauerová, Lenka

    2014-04-01

    Since it is known that UV-C radiation kills fungus, we wanted to verify the hypothesis that the use of excimer laser could be an alternative method for treating onychomycosis - nail fungus. The aim of the first stage of this work was to determine the transmission, reflection and absorption of nails. In the following stage we focused on irradiation of fungi. Our final task is to assess whether it is possible to determine the parameters of radiation (a total dose,a dose per pulse frequency, a repetition rate, a number of pulses) for which the elimination of fungi would be the most effective but without damaging the nail and soft tissue underneath it. The results so far have showed that UV-C radiation does not pass through a fingernail to such an extent that it could damage the soft tissue beneath it. Fungi are destroyed by the application of only small doses of radiation using the excimer laser. Additional measurements will be required to determine the modulation parameters of the excimer laser radiation for the treatment of onychomycosis.

  16. Lysosome-associated membrane proteins-1 and -2 (LAMP-1 and LAMP-2) assemble via distinct modes.

    PubMed

    Terasawa, Kazue; Tomabechi, Yuri; Ikeda, Mariko; Ehara, Haruhiko; Kukimoto-Niino, Mutsuko; Wakiyama, Motoaki; Podyma-Inoue, Katarzyna A; Rajapakshe, Anupama R; Watabe, Tetsuro; Shirouzu, Mikako; Hara-Yokoyama, Miki

    2016-10-21

    Lysosome-associated membrane proteins 1 and 2 (LAMP-1 and LAMP-2) have a large, heavily glycosylated luminal domain composed of two subdomains, and are the most abundant protein components in lysosome membranes. LAMP-1 and LAMP-2 have distinct functions, and the presence of both proteins together is required for the essential regulation of autophagy to avoid embryonic lethality. However, the structural aspects of LAMP-1 and LAMP-2 have not been elucidated. In the present study, we demonstrated that the subdomains of LAMP-1 and LAMP-2 adopt the unique β-prism fold, similar to the domain structure of the dendritic cell-specific-LAMP (DC-LAMP, LAMP-3), confirming the conserved aspect of this family of lysosome-associated membrane proteins. Furthermore, we evaluated the effects of the N-domain truncation of LAMP-1 or LAMP-2 on the assembly of LAMPs, based on immunoprecipitation experiments. We found that the N-domain of LAMP-1 is necessary, whereas that of LAMP-2 is repressive, for the organization of a multimeric assembly of LAMPs. Accordingly, the present study suggests for the first time that the assembly modes of LAMP-1 and LAMP-2 are different, which may underlie their distinct functions.

  17. Laser excited fluorescence in the cesium-xenon excimer and the cesium dimer

    NASA Technical Reports Server (NTRS)

    Exton, R. J.; Snow, W. L.; Hillard, M. E.

    1978-01-01

    Argon ion laser lines are used to excite fluorescence in a mixture of cesium and xenon. Excimer band fluorescence is observed at higher pressures (about 1 atm) while at lower pressures (several torr) a diffuse fluorescence due to the cesium dimer is observed whose character changes with exciting wavelength. The excimer fluorescence is shown to be directly related to the location of the exciting wavelength within previously measured Cs/Xe line shapes. This fact suggests that the excimer systems may be efficiently pumped through these line shapes. Qualitative energy-level schemes are proposed to explain the observations in both the excimer and dimer systems.

  18. 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.

  19. 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.

  20. Tungsten wire for incandescent lamps

    SciTech Connect

    Walter, J.L.; Briant, C.L. )

    1990-09-01

    Tungsten wire for incandescent lamp filaments must operate at high temperatures and for long times. To meet these requirements, the grain morphology of the wire must be controlled to reduce the propensity for grain boundary sliding. The morphology is a function of the distribution of very small pockets of potassium in the wire and the mechanical processing from ingot to wire. The behavior of the filament is directly related to the grain morphology. This paper describes the mechanism by which the potassium is incorporated into and distributed in the ingot. The elongation and spheroidization of the bubbles during hot rolling and swaging is also examined and related to the grain morphology of wire. Some indications of the relationship between grain morphology and filament behavior are also given.

  1. Excimer laser induced diffusion in magnetic semiconductor quantum wells

    NASA Astrophysics Data System (ADS)

    Howari, H.; Sands, D.; Nicholls, J. E.; Hogg, J. H. C.; Stirner, T.; Hagston, W. E.

    2000-08-01

    Studies of pulsed laser annealing (PLA) of CdTe/CdMnTe quantum well structures are made in order to examine depth dependent effects in laser irradiated semiconductors. Since diffusion coefficients are strongly dependent on the temperature, depth resolution is achieved because the diffusion of Mn from the barriers into the quantum wells is depth dependent. Multiple quantum well (MQW) structures of CdTe/CdMnTe were annealed with single pulses from an XeCl laser at 308 nm. At a threshold of 90 mJ cm-2 two new emission bands are observed that are attributed to the diffusion of Mn from barrier layers to QWs. The diffusion associated with these bands, measured as the integrated product of the diffusion constant and time, is found to be 300 and 30 Å2. Calculations of the temperature, reached within the surface following PLA, using an analytical solution of the heat diffusion equation coupled with known high temperature diffusion coefficients predict the diffusion to decrease by one order of magnitude within one period at the top of the MQW stack. It is suggested that at the threshold surface melting occurs and that these emission bands arise from the QWs immediately beneath the melt front. The diffusion of Mn ions into the QWs is confirmed by magneto-optical data. A further emission band occurs at this same threshold with a Mn concentration above that of the concentration in the barrier layers of the MQW stack. This emission is attributed tentatively to the segregation of the Mn ion within the molten region following recrystallization.

  2. 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.

  3. 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.

  4. Lamp system for uniform semiconductor wafer heating

    DOEpatents

    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.

  5. Excimer laser superficial keratectomy for proud nebulae in keratoconus.

    PubMed

    Moodaley, L; Liu, C; Woodward, E G; O'Brart, D; Muir, M K; Buckley, R

    1994-06-01

    Contact lens intolerance in keratoconus may be due to the formation of a proud nebula at or near the apex of the cone. Excimer laser superficial keratectomy was performed as an outpatients with proud nebulae as treatment patients with proud nebulae as treatment for their contact lens intolerance. The mean period of contact lens wear before the development of intolerance was 13.4 years (range 2 to 27 years). Following the development of intolerance, three patients abandoned contact lens wear in the affected eye while the remainder experienced a reduction in comfortable wearing time (mean = 3.75 hours; range: 0-14 hours). All patients had good potential Snellen visual acuity with a contact lens of 6/9 (nine eyes) and 6/12 (one eye). The proud nebulae were directly ablated with a 193 nm ArF excimer laser using a 1 mm diameter beam. Between 100-150 pulses were sufficient to ablate the raised area. Patients experienced no pain during the procedure and reported minimal discomfort postoperatively. In all cases flattening of the proud nebulae was achieved. Seven patients were able to resume regular contact lens wear (mean wearing time = 10.17 hours; range 8 to 16 hours). In three patients, resumption of contact lens wear was unsuccessful because of cone steepness. All patients achieved postoperative Snellen visual acuity of 6/12 or better with a contact lens. Four patients experienced a loss of one line in Snellen acuity. The mean follow up period was 8.3 months (range 2 to 17 months). Excimer laser superficial keratectomy is a useful technique for the treatment of contact lens intolerance caused by proud nebulae in patients with keratoconus. Penetrating keratoplasty is thus avoided.

  6. Integral CFLs performance in table lamps

    SciTech Connect

    Page, E.; Driscoll, D.; Siminovitch, M.

    1997-03-01

    This paper focuses on performance variations associated with lamp geometry and distribution in portable table luminaires. If correctly retrofit with compact fluorescent lamps (CFLs), these high use fixtures produce significant energy savings, but if misused, these products could instead generate consumer dissatisfaction with CFLs. It is the authors assertion that the lumen distribution of the light source within the luminaires plays a critical role in total light output, fixture efficiency and efficacy, and, perhaps most importantly, perceived brightness. The authors studied nearly 30 different integral (screw-based) CFLs available on the market today in search of a lamp, or group of lamps, which work best in portable table luminaires. The findings conclusively indicate that horizontally oriented CFLs outperform all other types of CFLs in nearly every aspect.

  7. 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

  8. Video equipment recommendations for slit lamp videography.

    PubMed

    Hammack, G G

    1991-08-01

    Current developments in video technology have made videotaping through a slit lamp a useful capability available at a more reasonable cost. The technical basis of equipment needed to select or design an apparatus for slit lamp videography is reviewed. As an overview, the optimum slit lamp video apparatus would have the following criteria; the slit lamp should have zoom optics and rheostat illumination, the beam splitter should be a mirror or 70/30 type, the camera should have maximal light sensitivity (101ux) with reasonable resolution (greater than 300 lines). The recorder should be SP-Umatic or Super VHS for documentation, or consumer VHS for patient education, and the monitor should be a professional 13- or 15-inch monitor.

  9. 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.

  10. Xenon excimer emission from multicapillary discharges in direct current mode

    SciTech Connect

    Lee, Byung-Joon; Rahaman, Hasibur; Nam, Sang Hoon; Giapis, Konstantinos P.; Iberler, Marcus; Jacoby, Joachim; Frank, Klaus

    2011-08-15

    Microdischarges in xenon have been generated in a pressure range of 400-1013 mbar with a fixed flow rate of 100 sccm. These microdischarges are obtained from three metallic capillary tubes in series for excimer emission. Total discharge voltage is thrice as large as that of a single capillary discharge tube at current levels of up to 12 mA. Total spectral irradiance of vacuum ultraviolet (VUV) emission also increases significantly compared to that of the single capillary discharge. Further, the irradiance of the VUV emission is strongly dependent on pressure as well as the discharge current.

  11. 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.

  12. Progress of excimer laser development in the AMMTRA project

    NASA Astrophysics Data System (ADS)

    Nagai, Haruhiko

    1993-05-01

    Since 1986, five kinds of excimer laser technologies have been studied by five companies as part of the large-scale project `Advanced Material-Processing and Machining System,' which is one of the national R&D projects in Japan. The five kinds of excimer lasers being developed are as follows: (1) high power XeCl laser with an average power of 2 kW, (2) high repetition rate XeCl laser with a repetition rate of 5 kHz, (3) automatically power-stabilized 400 W average power XeCl laser with a stability of +/- 1% or less, (4) long-life ArF laser with a gas life of 109 shots or more, and (5) high beam-quality ArF laser with an average power of 200 W. The project passed an interim evaluation at the end of fiscal 1990, and is now ongoing toward the achievement of final targets as of the end of fiscal 1993. The present status and future prospect of the technologies are reviewed.

  13. Excimer laser annealing to fabricate low cost solar cells

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The objective is to show whether or not pulsed excimer laser annealing (PELA) of ion-implanted junctions is a cost effective replacement for diffused junctions in fabricating crystalline silicon solar cells. The preliminary economic analysis completed shows that the use of PELA to fabricate both the front junction and back surface field (BSF) would cost approximately 35 cents per peak watt (Wp), compared to a cost of 15 cents/Wp for diffusion, aluminum BSF and an extra cleaning step in the baseline process. The cost advantage of the PELA process depends on improving the average cell efficiency from 14% to 16%, which would lower the overall cost of the module by about 15 cents/Wp. An optimized PELA process compatible with commercial production is to be developed, and increased cell efficiency with sufficient product for adequate statistical analysis demonstrated. An excimer laser annealing station was set-up and made operational. The first experiment used 248 nm radiation to anneal phosphorus implants in polished and texture-etched silicon.

  14. Excimer laser surface ablation: a review of recent literature.

    PubMed

    O'Brart, David P S

    2014-01-01

    The aim was to review the recently published literature on excimer laser surface ablation procedures, including photorefractive keratectomy (PRK), laser sub-epithelial keratomileusis (LASEK), microkeratome-assisted PRK (epi-LASIK) and trans-epithelial (laser-assisted) PRK, to help elucidate where and how surface ablation may best fit into current refractive surgical practice. The emphasis was on publications within the last three years and included systemic reviews, meta-analyses and randomised controlled trials. Where such evidence did not exist, selective large series cohort studies, case-controlled studies and case series with follow-up preferably greater than six months were examined and included. Refractive and visual outcomes are excellent and comparable to those after LASIK even in complex cases after previous corneal surgery. Indeed, surface ablation combined with corneal collagen cross-linking may be used in selected eyes with biomechanical instability, where LASIK is contraindicated. In addition, there is evidence to suggest that there may be less induction of higher order aberrations with surface techniques. Long-term stability and safety appear to be extremely satisfactory. The literature supports the use of modern excimer laser surface treatments, with outcomes comparable to those after LASIK and evidence of less induction of higher-order aberrations. Follow-up studies at 10 to 20 years indicate excellent stability and safety.

  15. Solid sampling with 193-nm excimer laser ablation

    NASA Astrophysics Data System (ADS)

    Delmdahl, Ralph

    2007-02-01

    Reproducible and sensitive elemental analysis of solid samples is a crucial task in areas of geology (e.g. microanalysis of fluid inclusions), material sciences, industrial quality control as well as in environmental, forensic and biological studies. To date the most versatile detection method is mass-spectroscopic multi-element analysis. In order to obtain reproducible results, this requires transferring the solid sample into the gas-phase while preserving the sample's stoichiometric composition. Laser ablation in combination with Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) is a proven powerful technique to meet the requirements for reliable solid sample analysis. The sample is laser ablated in an air-tight cell and the aerosol is carried by an inert gas to a micro-wave induced plasma where its constituents are atomized and ionized prior to mass analysis. The 193 nm excimer laser ablation, in particular, provides athermal sample ablation with very precise lateral ablation and controlled depth profiling. The high photon energy and beam homogeneity of the 193 nm excimer laser system avoids elemental fractionation and permits clean ablation of even transmissive solid materials such as carbonates, fluorites and pure quartz.

  16. Excimer laser ablation for spatially controlled protein patterns

    NASA Astrophysics Data System (ADS)

    Thissen, Helmut; Hayes, Jason P.; Kingshott, Peter; Johnson, Graham; Harvey, Erol C.; Griesser, Hans J.

    2001-11-01

    Two-dimensional control over the location of proteins on surfaces is desired for a number of applications including diagnostic tests and tissue engineered medical devices. Many of these applications require patterns of specific proteins that allow subsequent two-dimensionally controlled cell attachment. The ideal technique would allow the deposition of specific protein patterns in areas where cell attachment is required, with complete prevention of unspecific protein adsorption in areas where cells are not supposed to attach. In our study, collagen I was used as an example for an extracellular matrix protein known to support the attachment of bovine corneal epithelial cells. An allylamine plasma polymer was deposited on a silicon wafer substrate, followed by grafting of poly(ethylene oxide). Two-dimensional control over the surface chemistry was achieved using a 248 nm excimer laser. Results obtained by XPS and AFM show that the combination of extremely low-fouling surfaces with excimer laser ablation can be used effectively for the production of spatially controlled protein patterns with a resolution of less than 1 micrometers . Furthermore, it was shown that bovine corneal epithelial cell attachment followed exactly the created protein patterns. The presented method is an effective tool for a number of in vitro and in vivo applications.

  17. 49 CFR 393.9 - Lamps operable, prohibition of obstructions of lamps and reflectors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... required by this subpart shall be capable of being operated at all times. This paragraph shall not be construed to require that any auxiliary or additional lamp be capable of operating at all times. (b) Lamps... any part of the load, or its covering by dirt, or other added vehicle or work equipment, or...

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

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 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...

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 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...

  20. 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

  1. 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

  2. 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.

  3. Excimer laser annealing for fabrication of low-cost solar cells

    NASA Technical Reports Server (NTRS)

    Spitzer, M. B.; Greenwald, A. C.; Hogan, S. J.

    1985-01-01

    Pulsed excimer laser annealing was successfully performed using a 50 w laser. Both polished and texturized cells were tried, however, there are serious problems with nonuniformity on texturized cells. A number of cells were produced and compared to diffusion furnace annealed cells. There was no clear economic advantage in using an excimer laser and there was a small penalty on average efficiency. The conclusion was that the excimer laser anneal process must be able to produce superior cells to be considered as a viable process option.

  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.

    2014-12-01

    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. Basics of lava-lamp convection.

    PubMed

    Gyüre, Balázs; Jánosi, Imre M

    2009-10-01

    Laboratory experiments are reported in an immiscible two-fluid system, where thermal convection is initiated by heating at the bottom and cooling at the top. The lava-lamp regime is characterized by a robust periodic exchange process where warm blobs rise from the bottom, attach to the top surface for a while, then cold blobs sink down again. Immiscibility allows to reach real steady (dynamical equilibrium) states which can be sustained for several days. Two modes of lava-lamp convection could be identified by recording and evaluating temperature time series at the bottom and at the top of the container: a "slow" mode is determined by an effective heat transport speed at a given temperature gradient, while a second mode of constant periodicity is viscosity limited. Contrasting of laboratory and geophysical observations yields the conclusion that the frequently suggested lava-lamp analogy fails for the accepted models of mantle convection.

  6. Effect of beam variables on corneal sensitivity after excimer laser photorefractive keratectomy

    PubMed Central

    Lawrenson, J.; Corbett, M.; O'Brart, D.; Marshall, J.

    1997-01-01

    AIM—To investigate changes in corneal touch sensitivity following excimer laser photorefractive keratectomy (PRK) using different beam configurations.
METHODS—20 subjects were given a unilateral −3.00 D correction with either a 5 mm (26 µm, n=10) or 6 mm (42 µm, n=10) beam diameter. Thirty subjects underwent a unilateral −6.00 D correction with 5 mm (62 µm, n=10), 6 mm (78 µm, n=10), or multizone (62 µm, n=10) treatments. The multizone treatment was 6 mm in diameter with the depth of the 5 mm treatment. Corneal sensitivity was measured using a slit-lamp mounted Cochet-Bonnet aesthesiometer before and at 1, 3, 6, and 12 months after PRK. Stimulus locations included points lying within the ablated zone (central) and outside (peripheral). These were compared with the equivalent locations in control (untreated) eyes.
RESULTS—There was a significant reduction in corneal sensitivity within the central (ablated) zone in all treatment groups after PRK. In most groups a return to full sensitivity was achieved by 6 months with the exception of the multizone treatment group which showed significant corneal hypoaesthesia at 12 months. Peripheral corneal sensitivity was also reduced in this group up to 3 months after the procedure. A comparison between the −3.00 D and −6.00 D treatment groups showed no significant difference. However, combining data from all treatment groups, a significant correlation was found between the interocular difference in central corneal sensitivity and postoperative haze at 3 and 6 months.
CONCLUSIONS—For corrections up to −6.00 D ablation depth and treatment zone diameter do not appear to be clinically important determinants of corneal hypoaesthesia. In contrast, postoperative corneal haze appears to correlate with sensitivity loss.

 PMID:9349159

  7. SBC Internal Lamp P-flat Monitoring

    NASA Astrophysics Data System (ADS)

    Avila, R. J.; Chiaberge, M.; Bohlin, R.

    2016-03-01

    We report on a Cycle 23 calibration program to monitor the status of the SBC P-flat. We find random pixel to pixel changes to be small, with only 2% of pixels having changed by more than 3. There are coherent changes that we measure to be above the poisson errors, in some regions as high as 4% peak to peak. We recommend that the ACS team obtain new observations in order to create a new P-flat. We also measured the degradation of the deuterium lamp used to create internal flats. The brightness of the lamp is currently 65% of its initial level, the degradation being dependent on lifetime usage.

  8. 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

  9. 30 CFR 57.12035 - Weatherproof lamp sockets.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Surface and Underground § 57.12035 Weatherproof lamp sockets. Lamp sockets shall be of a weatherproof type where they are exposed to weather or wet conditions that may interfere with illumination or create...

  10. 30 CFR 75.522-1 - Incandescent and fluorescent lamps.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... crosscut, incandescent lamps may be used to illuminate underground areas. When incandescent lamps are used in a track entry or belt entry or near track entries to illuminate special areas other...

  11. 30 CFR 75.522-1 - Incandescent and fluorescent lamps.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... crosscut, incandescent lamps may be used to illuminate underground areas. When incandescent lamps are used in a track entry or belt entry or near track entries to illuminate special areas other...

  12. 49 CFR 393.23 - Power supply for lamps.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.23 Power supply for... exception of battery powered lamps used on projecting loads. [70 FR 48046, Aug. 15, 2005]...

  13. Circular, explosion-proof lamp provides uniform illumination

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Circular explosion-proof fluorescent lamp is fitted around a TV camera lens to provide shadowless illumination with a low radiant heat flux. The lamp is mounted in a transparent acrylic housing sealed with clear silicone rubber.

  14. Detail view of lamp in law library; Jennewein modeled symbols ...

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

    Detail view of lamp in law library; Jennewein modeled symbols of the four seasons on the lamp's aluminum supports - United States Department of Justice, Constitution Avenue between Ninth & Tenth Streets, Northwest, Washington, District of Columbia, DC

  15. Lamp automatically switches to new filament on burnout

    NASA Technical Reports Server (NTRS)

    Ingle, W. B.

    1966-01-01

    Lamp with primary and secondary filaments has a means for automatic switching to the secondary filament at primary filament burnout. Lamp failures and resultant expenses during oscillograph printing are appreciably reduced.

  16. Acute And Long-Term Bioeffects And Lamp Safety

    NASA Astrophysics Data System (ADS)

    Andersen, F. Alan

    1980-10-01

    Knowledge of both acute and chronic biological effects is currently used to evaluate lamp safety. In some cases, a quantitative basis for avoiding exposures greater than a certain value can be stated. In other cases, however, only a qualitative estimate of the hazard is available. In a discussion that uses mercury vapor lamps, tanning booths, and sodium vapor lamps as examples, the interplay between the two types of data leading to an evaluation of lamp safety is described.

  17. Aggregation-controlled excimer emission from anthracene-containing polyamidoamine dendrimers.

    PubMed

    Lekha, P K; Prasad, Edamana

    2010-03-22

    Lower generations of polyamidoamine (PAMAM) dendrimers were peripherally modified with anthracene moieties, and excimer emission from anthracene chromophores was investigated in an acetonitrile-water mixture at acidic and basic pH values. Results from fluorescence spectroscopic experiments suggest that 1) the propensity of anthracene-modified PAMAM dendrimers to aggregate in acetonitrile is substantial in the presence of 15-20 vol % of water, and 2) aggregate formation in anthracene-modified PAMAM dendrimers leads to unique morphologies in the ground state, where the anthracene units are pre-arranged to form stable excimers upon photoexcitation. Three types of anthracene excimers are generated in the system, with face-to-face, angular, and T-shaped geometry. The formation of different types of anthracene excimers was confirmed by steady-state and time-resolved fluorescence spectroscopic experiments. Experimental results further suggest that it is feasible to alter the type of excimer formed by anthracene units attached to the PAMAM dendrimers through altering the propensity for ground-state aggregation. Most excitingly, increased pi conjugation in the molecular framework of anthracene-substituted PAMAM dendrimers leads to intense and exclusive excimer emission from anthracene at room temperature.

  18. Study of efficacy in a mercury-free flat discharge fluorescent lamp using a zero-dimensional positive column model

    NASA Astrophysics Data System (ADS)

    Shiga, T.; Pitchford, L. C.; Boeuf, J.-P.; Mikoshiba, S.

    2003-03-01

    A zero-dimensional model of the positive column in Ar/Ne/Xe gas mixtures has been developed to help understand the measured dependence of the efficacy on operating conditions in a mercury-free flat fluorescent lamp in a dielectric barrier geometry. The experimental conditions are such that the radiation from the discharge is homogeneous over most of the discharge voltage. The model uses as input the discharge current waveform from the experiments, and it yields the time variations of the mean electron energy and the species densities. From these quantities we calculate the number of vacuum ultraviolet (VUV) photons emitted by the xenon resonance atoms and excimers during one current pulse and the efficiency for generation of VUV radiation in the positive column, which are compared with the measured luminance and efficacy for various voltages, pulse intervals, and lamp sizes. Over the range of conditions studied, we find that most electrical energy dissipated in xenon excitation is converted to VUV radiation; i.e. the losses of xenon excitation in stepwise and associative ionization processes are small. When the mean electron energy is low, energy dissipation in elastic momentum transfer collisions leads to a decrease in the efficiency. On the other hand, ionization and excitation of argon degrade the efficiency when the mean electron energy is high. To a lesser extent, stepwise excitation of the xenon metastables also decreases the efficiency for high current densities.

  19. Blackbody Radiation from an Incandescent Lamp

    ERIC Educational Resources Information Center

    Ribeiro, C. I.

    2014-01-01

    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.…

  20. Fluorescent lamp with non-scattering phosphor

    SciTech Connect

    Johnson, P.D.

    1984-09-04

    A fluorescent lamp comprises a source of near ultraviolet radiation together with an outer shell at least partially surrounding the ultraviolet source and comprising an ultraviolet transmissive material, the shell having embedded or dissolved therein a phosphor material having an indexed refraction approximately, but not quite equal, to the index of refraction of the shell.

  1. Flight vehicle thermal testing with infrared lamps

    NASA Technical Reports Server (NTRS)

    Fields, Roger A.

    1992-01-01

    The verification and certification of new structural material concepts for advanced high speed flight vehicles relies greatly on thermal testing with infrared quartz lamps. The basic quartz heater system characteristics and design considerations are presented. Specific applications are illustrated with tests that were conducted for the X-15, the Space Shuttle, and YF-12 flight programs.

  2. Breakdown characteristics of xenon HID Lamps

    NASA Astrophysics Data System (ADS)

    Babaeva, Natalia; Sato, Ayumu; Brates, Nanu; Noro, Koji; Kushner, Mark

    2009-10-01

    The breakdown characteristics of mercury free xenon high intensity discharge (HID) lamps exhibit a large statistical time lag often having a large scatter in breakdown voltages. In this paper, we report on results from a computational investigation of the processes which determine the ignition voltages for positive and negative pulses in commercial HID lamps having fill pressures of up to 20 atm. Steep voltage rise results in higher avalanche electron densities and earlier breakdown times. Circuit characteristics also play a role. Large ballast resistors may limit current to the degree that breakdown is quenched. The breakdown voltage critically depends on cathode charge injection by electric field emission (or other mechanisms) which in large part controls the statistical time lag for breakdown. For symmetric lamps, ionization waves (IWs) simultaneously develop from the bottom and top electrodes. Breakdown typically occurs when the top and bottom IWs converge. Condensed salt layers having small conductivities on the inner walls of HID lamps and on the electrodes can influence the ignition behavior. With these layers, IWs tend to propagate along the inner wall and exhibit a different structure depending on the polarity.

  3. 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.

  4. Basic physics of the incandescent lamp (lightbulb)

    NASA Astrophysics Data System (ADS)

    MacIsaac, Dan; Kanner, Gary; Anderson, Graydon

    1999-12-01

    We describe the basic electrical and optical characteristics of the incandescent lamp (lightbulb), as an appropriate exemplar for use in teaching introductory electricity and magnetism. We discuss filament characteristics, blackbody physics, mechanical bulb manufacture, and halogen technology. Variants of the incandescent bulb are also addressed.

  5. Heat Lamps Solder Solar Array Quickly

    NASA Technical Reports Server (NTRS)

    Coyle, P. J.; Crouthamel, M. S.

    1982-01-01

    Interconnection tabs in a nine-solar-cell array have been soldered simultaneously with radiant heat. Cells and tabs are held in position for soldering by sandwiching them between compliant silicone-rubber vacuum platen and transparent polyimide sealing membrane. Heat lamps warm cells, producing smooth, flat solder joints of high quality.

  6. Illuminating the Mathematics of Lamp Shades

    ERIC Educational Resources Information Center

    Matthews, Michael E.; Gross, Greg

    2008-01-01

    The problem of creating lamp shades to specific design parameters allows rich and interesting explorations in the mathematics of circles and triangles. This interactive project helps students build their spatial reasoning and is especially appropriate during a unit on either the Pythagorean theorem or similar triangles. (Contains 7 figures and 1…

  7. 146. DETAIL VIEW, LOOKING STRAIGHT ON, OF CAST IRON LAMP ...

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

    146. DETAIL VIEW, LOOKING STRAIGHT ON, OF CAST IRON LAMP STANDARD. THIS AND OTHER LAMP STANDARDS WERE REMOVED FROM THE LAMP COLUMNS ON THE PARAPET WALLS DURING WORLD WAR II AND STORED INSIDE THE DAM (January 1991) - Coolidge Dam, Gila River, Peridot, Gila County, AZ

  8. 46 CFR 72.03-15 - Lamp room construction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Lamp room construction. 72.03-15 Section 72.03-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 72.03-15 Lamp room construction. (a) Lamp, paint, and oil lockers...

  9. 30 CFR 75.522-1 - Incandescent and fluorescent lamps.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... structures, the lamps shall be installed in weather-proof sockets located in positions such that the lamps... or fluorescent lamps may be used inside underground structures (except magazines used for the storage of explosives and detonators). In underground structures lighting circuits shall consist of...

  10. 30 CFR 75.522-1 - Incandescent and fluorescent lamps.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... structures, the lamps shall be installed in weather-proof sockets located in positions such that the lamps... or fluorescent lamps may be used inside underground structures (except magazines used for the storage of explosives and detonators). In underground structures lighting circuits shall consist of...

  11. 30 CFR 75.522-1 - Incandescent and fluorescent lamps.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... structures, the lamps shall be installed in weather-proof sockets located in positions such that the lamps... or fluorescent lamps may be used inside underground structures (except magazines used for the storage of explosives and detonators). In underground structures lighting circuits shall consist of...

  12. 30 CFR 75.1703 - Portable electric lamps.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Portable electric lamps. 75.1703 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703 Portable electric lamps. Persons underground shall use only permissible electric lamps approved by the Secretary for...

  13. 30 CFR 75.1703 - Portable electric lamps.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Portable electric lamps. 75.1703 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703 Portable electric lamps. Persons underground shall use only permissible electric lamps approved by the Secretary for...

  14. 30 CFR 75.1703 - Portable electric lamps.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Portable electric lamps. 75.1703 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703 Portable electric lamps. Persons underground shall use only permissible electric lamps approved by the Secretary for...

  15. 30 CFR 75.1703 - Portable electric lamps.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Portable electric lamps. 75.1703 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703 Portable electric lamps. Persons underground shall use only permissible electric lamps approved by the Secretary for...

  16. 30 CFR 75.1703 - Portable electric lamps.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Portable electric lamps. 75.1703 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703 Portable electric lamps. Persons underground shall use only permissible electric lamps approved by the Secretary for...

  17. 46 CFR 92.05-10 - Lamp room construction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Lamp room construction. 92.05-10 Section 92.05-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 92.05-10 Lamp room construction. (a) Lamp, paint,...

  18. 49 CFR 230.56 - Water glass lamps.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Water glass lamps. 230.56 Section 230.56... Water Glasses and Gauge Cocks § 230.56 Water glass lamps. All water glasses must be supplied with a suitable lamp properly located to enable the engine crew to easily see the water in the glass....

  19. 49 CFR 230.56 - Water glass lamps.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Water glass lamps. 230.56 Section 230.56... Water Glasses and Gauge Cocks § 230.56 Water glass lamps. All water glasses must be supplied with a suitable lamp properly located to enable the engine crew to easily see the water in the glass....

  20. 49 CFR 230.56 - Water glass lamps.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Water glass lamps. 230.56 Section 230.56... Water Glasses and Gauge Cocks § 230.56 Water glass lamps. All water glasses must be supplied with a suitable lamp properly located to enable the engine crew to easily see the water in the glass....

  1. 49 CFR 230.56 - Water glass lamps.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Water glass lamps. 230.56 Section 230.56... Water Glasses and Gauge Cocks § 230.56 Water glass lamps. All water glasses must be supplied with a suitable lamp properly located to enable the engine crew to easily see the water in the glass....

  2. Prevention of distal embolization and no-reflow in patients with acute myocardial infarction and total occlusion in the infarct-related vessel: a subgroup analysis of the cohort of acute revascularization in myocardial infarction with excimer laser-CARMEL multicenter study.

    PubMed

    Dahm, Johannes B; Ebersole, Douglas; Das, Tony; Madyhoon, Hooman; Vora, Kishor; Baker, John; Hilton, David; Topaz, On

    2005-01-01

    To overcome the adverse complications of percutaneous coronary interventions in thrombus laden lesions (i.e., distal embolization, platelet activation, no-reflow phenomenon), mechanical removal of the thrombus or distal embolization protection devices are frequently required. Pulsed-wave ultraviolet excimer laser light at 308 nm can vaporize thrombus, suppress platelet aggregation, and, unlike other thrombectomy devices, ablate the underlying plaque. The following multicenter registry was instituted to evaluate the safety and efficacy of laser ablation in patients presenting with acute myocardial infarction (AMI) complicated by persistent thrombotic occlusions. Patients with AMI and complete thrombotic occlusion of the infarct-related vessel were included in eight participating centers. Patients with further compromising conditions (i.e., cardiogenic shock, thrombolysis failures) were also included. Primary endpoint was procedural respective laser success; secondary combined endpoints were TIMI flow and % stenosis by quantitative coronary analysis and visual assessment at 1-month follow-up. Eighty-four percent of all patients enrolled (n = 56) had a very large thrombus burden (TIMI thrombus scale > or = 3), and 49% were compromised by complex clinical presentation, i.e., cardiogenic shock (21%), degenerated saphenous vein grafts (26%), or thrombolysis failures (5%). Laser success was achieved in 89%, angiographic success in 93%, and the overall procedural success rate was 86%. The angiographic prelaser total occlusion was reduced angiographically to 58% +/- 25% after laser treatment and to 4% +/- 13% final residual stenosis after adjunctive balloon angioplasty and/or stent placement. TIMI flow increased significantly from grade 0 to 2.7 +/- 0.5 following laser ablation (P < 0.001) and 3.0 +/- 0.2 upon completion of the angioplasty procedure (P > 0.001 vs. baseline). Distal embolizations occurred in 4%, no-reflow was observed in 2%, and perforations in 0.6% of cases

  3. The 308-nm Laser Photodissociation of HN3 Adsorbed on Si(111)-7X7

    DTIC Science & Technology

    1993-01-01

    and M. Nishijima; Surface Sci. 191 (1987) L756. [3] C.U.S. Larsson, and A.S. Flodstrom; Surface Sci. 241 (1991) 353. [4] E.K. Hlil, L. Kubler , J.L...Bischoff, F. Lutz, D. Bolmont, and L. Kubler ; Surface Sci. 251 (1991) 170. [7] D.G. Kilday, G. Margartondo, D.J. Frankel, J. Anderson, and G.J. Lapeyre; Phys...Rev. B35 (1987) 9364. [8] T. Isu, and K. Fujiwaraf; Solid State Commun. 42 (1982) 477. [9] L. Kubler , E.K. Hlil, D. Bolmont, and G. Gewinner

  4. 75 FR 22213 - Energy Conservation Program: Test Procedures for General Service Fluorescent Lamps, Incandescent...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-28

    ... Lamps, Incandescent Reflector Lamps, and General Service Incandescent Lamps; Correction AGENCY: Office... procedures for general service fluorescent lamps, incandescent reflector lamps, and general service incandescent lamps, which was published in the Federal Register on July 6, 2009. In that final rule, the...

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

    SciTech Connect

    none,

    2014-12-31

    This CALiPER report examines the characteristics of a subset of lamps from CALiPER Retail Lamps Study 3 in more detail. Specifically, it focuses on the dimming, power quality, and flicker characteristics of 14 LED A lamps, as controlled by four different retail-available dimmers.

  6. Controlling the vapor pressure of a mercury lamp

    DOEpatents

    Grossman, M.W.; George, W.A.

    1988-05-24

    The invention described herein discloses a method and apparatus for controlling the Hg vapor pressure within a lamp. This is done by establishing and controlling two temperature zones within the lamp. One zone is colder than the other zone. The first zone is called the cold spot. By controlling the temperature of the cold spot, the Hg vapor pressure within the lamp is controlled. Likewise, by controlling the Hg vapor pressure of the lamp, the intensity and linewidth of the radiation emitted from the lamp is controlled. 2 figs.

  7. [Remote Slit Lamp Microscope Consultation System Based on Web].

    PubMed

    Chen, Junfa; Zhuo, Yong; Liu, Zuguo; Chen, Yanping

    2015-11-01

    To realize the remote operation of the slit lamp microscope for department of ophthalmology consultation, and visual display the real-time status of remote slit lamp microscope, a remote slit lamp microscope consultation system based on B/S structure is designed and implemented. Through framing the slit lamp microscope on the website system, the realtime acquisition and transmission of remote control and image data is realized. The three dimensional model of the slit lamp microscope is established and rendered on the web by using WebGL technology. The practical application results can well show the real-time interactive of the remote consultation system.

  8. Comparative studies on dimming capabilities of retrofit LED lamps

    NASA Astrophysics Data System (ADS)

    Ionescu, Ciprian; Vasile, Alexandru; Codreanu, Norocel; Negroiu, Rodica

    2016-12-01

    These days many variants for lighting systems are available on the market, and new solutions are about to emerge. Most of the new lamps are offered in form to be retrofitted to existing sockets and luminaires. In this paper, are presented some systematically investigations on different lamps as LEDs, Compact Fluorescent Lamps (CFLs), tungsten, and new available Cold Cathode Fluorescent Lamps (CCFLs), regarding the light level, dimming performances and also the resulting flicker and power distortion performances. The light level was expressed by the illuminance level, measured for all lamps in the same conditions, at the same distance and on the same surface represented by the photometer probe.

  9. Controlling the vapor pressure of a mercury lamp

    DOEpatents

    Grossman, Mark W.; George, William A.

    1988-01-01

    The invention described herein discloses a method and apparatus for controlling the Hg vapor pressure within a lamp. This is done by establishing and controlling two temperature zones within the lamp. One zone is colder than the other zone. The first zone is called the cold spot. By controlling the temperature of the cold spot, the Hg vapor pressure within the lamp is controlled. Likewise, by controlling the Hg vapor pressure of the lamp, the intensity and linewidth of the radiation emitted from the lamp is controlled.

  10. Novel Nanophosphors for High Efficiency Fluorescent Lamps

    SciTech Connect

    Alok Srivatava

    2007-03-31

    This is the Final Report of the Novel Nanophosphors for High Efficiency Fluorescent Lamps, Department of Energy (DOE). The overall goal of this three-year program is to develop novel hybrid phosphors by coating commercially available lamp phosphors with highly stable wide band-gap nanocrystalline phosphors (NCP). The prime technical approach is the development of NCP quantum-splitting phosphor (QSP) and ultra-violet (UV) emitting phosphors with quantum efficiencies exceeding that of the conventional phosphors at 185 nm. The novel hybrid phosphors will increase the efficiency of the fluorescent lamps by up to 32%, enabling total energy savings of 0.26 quads, the reduction in the U.S. energy bill by $6.5 billion and the reduction of the annual carbon emission by 4.1 billion kilogram. Our work started by investigating through modeling calculations the requirement for the particle size of the NCP. Our work to develop suitable nanocrystalline phosphors started with the known oxide quantum splitting and UV emitting phosphors. We demonstrated several synthesis techniques for the production of high quality nanocrystalline materials that crystallizes in the desired phase and with the desired particle size. In collaboration with our subcontractor we demonstrated the feasibility for the manufacture of NC phosphors. We also demonstrated novel techniques of coating the NCP on the surface of micron sized phosphors. Our chief achievement pertains to the successful testing of the coated hybrid phosphor systems in linear fluorescent lamps. In linear fluorescent lamp tests, we have demonstrated up to 7% increase in the efficacy of hybrid phosphors over the conventional (uncoated) phosphors. We have also demonstrated the improvement in the lumen maintenance of the coated phosphors. A hybrid phosphor system based on the commercial red emitting phosphor, Y{sub 2}O{sub 3}:Eu{sup 3+} did not show the anticipated improvement in lamp efficacy. We explored the reasons for this observation

  11. Lamp reliability studies for improved satellite rubidium frequency standard

    NASA Technical Reports Server (NTRS)

    Frueholz, R. P.; Wun-Fogle, M.; Eckert, H. U.; Volk, C. H.; Jones, P. F.

    1982-01-01

    In response to the premature failure of Rb lamps used in Rb atomic clocks onboard NAVSTAR GPS satellites experimental and theoretical investigations into their failure mechanism were initiated. The primary goal of these studies is the development of an accelerated life test for future GPS lamps. The primary failure mechanism was identified as consumption of the lamp's Rb charge via direct interaction between Rb and the lamp's glass surface. The most effective parameters to accelerate the interaction between the Rb and the glass are felt to be RF excitation power and lamp temperature. Differential scanning calorimetry is used to monitor the consumption of Rb within a lamp as a function of operation time. This technique yielded base line Rb consumption data for GPS lamps operating under normal conditions.

  12. Lamp-life predictive model for avionics backlights

    NASA Astrophysics Data System (ADS)

    Webster, Richard P.; Nelson, Leonard Y.

    1998-09-01

    Active Matrix Liquid Crystal Displays (AMLCDs) used in avionics applications require high luminance, high efficacy, and long-life backlights. Currently, fluorescent lamps are the favored light sources for these high performance avionics backlights. Their spectral characteristics and high electrical efficiency are well suited to illuminating AMLCDs used in avionics applications. Fluorescent lamps, however, suffer gradual reduction in luminance output caused by various degradation mechanisms. Korry Electronics Co. recently developed a mathematical model for predicting fluorescent lamp life. The model's basis is the well characterized exponential decay of the phosphor output. The primary luminance degradation mechanism of a fluorescent lamp is related to the arc discharge. Consequently, phosphor depreciation is proportional to the discharge arc power divided by the phosphor surface area. This 'wall loading' is a parameter in the computer model developed to extrapolate long-term luminance performance. Our model predicts a rapidly increasing decay rate of the lamp output as the input power is increased to sustain constant luminance. Eventually, a run-away condition occurs -- lamp arc power must be increased by unrealistically large factors (greater than 5x) to maintain the required luminance output. This condition represents the end of the useful lamp life. The lamp life model requires the definition of several key parameters in order to accurately predict the useful lamp life of an avionics backlight. These important factors include the construction of the lamp, lamp arc power, a decay constant based on the phosphor loading, and the operational profile. Based on the above-mentioned factors, our model approximates the useful lamp life of an avionics backlight using fluorescent lamp technology. Comparisons between calculated and experimental lamp depreciation are presented.

  13. The lake acidification mitigation project (LAMP)

    SciTech Connect

    Porcella, D.P. )

    1987-01-01

    In areas where there is limited capacity to resist input of acid deposition, acid soils and surface waters have affected natural communities and man's uses of the environment. In response to problems of acid soils, farmers added limestone materials to their soil during Roman times; this method of agricultural management continues today. The addition of limestone (CaCo/sub 3/), called liming, has been used more recently to mitigate acidic conditions in lakes and streams. Liming neutralizes acidity directly, provides buffering as acid neutralizing capacity (ANC) or alkalinity, and increases calcium ion concentration which mitigates toxicity in low ionic strength waters. The Lake Acidification Mitigation Project (LAMP) has the objective of identifying and quantifying environmental impacts of liming, and evaluating the effectiveness of liming and stocking procedures in restoring acid lakes. The purpose of this paper is to provide an overview of LAMP and to summarize results from the initial phases of the project.

  14. LED lamp color control system and method

    DOEpatents

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

    2013-02-05

    An LED lamp color control system and method including an LED lamp having an LED controller 58; and 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 determines whether the LED source 80 is in a feedback controllable range, stores measured optical flux for the LED source 80 when the LED source 80 is in the feedback controllable range, and bypasses storing the measured optical flux when the LED source 80 is not in the feedback controllable range.

  15. Excimer laser crystallization of amorphous silicon on metallic substrate

    NASA Astrophysics Data System (ADS)

    Delachat, F.; Antoni, F.; Slaoui, A.; Cayron, C.; Ducros, C.; Lerat, J.-F.; Emeraud, T.; Negru, R.; Huet, K.; Reydet, P.-L.

    2013-06-01

    An attempt has been made to achieve the crystallization of silicon thin film on metallic foils by long pulse duration excimer laser processing. Amorphous silicon thin films (100 nm) were deposited by radiofrequency magnetron sputtering on a commercial metallic alloy (N42-FeNi made of 41 % of Ni) coated by a tantalum nitride (TaN) layer. The TaN coating acts as a barrier layer, preventing the diffusion of metallic impurities in the silicon thin film during the laser annealing. An energy density threshold of 0.3 J cm-2, necessary for surface melting and crystallization of the amorphous silicon, was predicted by a numerical simulation of laser-induced phase transitions and witnessed by Raman analysis. Beyond this fluence, the melt depth increases with the intensification of energy density. A complete crystallization of the layer is achieved for an energy density of 0.9 J cm-2. Scanning electron microscopy unveils the nanostructuring of the silicon after laser irradiation, while cross-sectional transmission electron microscopy reveals the crystallites' columnar growth.

  16. Excimer Laser Beam Analyzer Based on CVD Diamond

    NASA Astrophysics Data System (ADS)

    Girolami, Marco; Salvatori, Stefano; Conte, Gennaro

    2010-11-01

    1-D and 2-D detector arrays have been realized on CVD-diamond. The relatively high resistivity of diamond in the dark allowed the fabrication of photoconductive "sandwich" strip (1D) or pixel (2D) detectors: a semitransparent light-receiving back-side contact was used for detector biasing. Cross-talk between pixels was limited by using intermediate guard contacts connected at the same ground potential of the pixels. Each pixel photocurrent was conditioned by a read-out electronics composed by a high sensitive integrator and a Σ-Δ ADC converter. The overall 500 μs conversion time allowed a data acquisition rate up to 2 kSPS. The measured fast photoresponse of the samples in the ns time regime suggests to use the proposed devices for fine tuning feedback of high-power pulsed-laser cavities, whereas solar-blindness guarantees high performance in UV beam diagnostics also under high intensity background illumination. Offering unique properties in terms of thermal conductivity and visible-light transparency, diamond represents one of the most suitable candidate for the detection of high-power UV laser emission. The technology of laser beam profiling is evolving with the increase of excimer lasers applications that span from laser-cutting to VLSI and MEMS technologies. Indeed, to improve emission performances, fine tuning of the laser cavity is required. In such a view, the development of a beam-profiler, able to work in real-time between each laser pulse, is mandatory.

  17. Excimer laser induced surface chemical modification of polytetrafluoroethylene

    NASA Astrophysics Data System (ADS)

    Révész, K.; Hopp, B.; Bor, Z.

    1997-02-01

    Polytetrafluoroethylene has a notoriously non adhesive and non reactive character. Its successful surface photochemical modification was performed by irradiating the polytetrafluoroethylene/liquid triethylamine interface with an ArF excimer laser (λ=193 nm). Due to the photochemical treatment the polytetrafluoroethylene surface became more hydrophilic. The water receding contact angle decreased from 94° to 43°. The reaction cross section was determined from the decrease of the contact angles. It was found to be as high as 6.4×10-18 cm2. XPS measurements evidenced the removal of fluorine from the polytetrafluoroethylene, incorporation of alkyl carbon and nitrogen. Photochemical dissociation path of the triethylamine makes probable that it bonded to the fluoropolymer backbone via the α-carbon atom of an ethyl group. A radical, or a photoinduced electron transfer mechanism was suggested to describe this reaction. A selective area electroless plating of silver was performed after pretreating the sample with patterned photomodification. The increased adhesion of the sample was proved by gluing with epoxy resin. As a result of the surface modification the tensile strength of gluing increased by 210× and reached 24% of the value characteristic for the bulk material.

  18. Excimer radiation from pulsed micro hollow cathode discharges

    NASA Astrophysics Data System (ADS)

    Petzenhauser, Isfried; Ernst, Uwe; Frank, Klaus

    2001-10-01

    Since several years d.c. microhollow cathode discharges (MHCDs) are under investigation as efficient sources of VUV excimer radiation [1]. Up to now overall efficiency and the radiation power of the MHCDs are too low to compete e.g. with silent discharges. Substantial improvement in these parameters would make by its simple geometry MCHDs attractive for a wide range of applications. Experiments and simulations show that the efficiency of MCHDs is substantially reduced by high gas temperatures beyond 1500 K. Measurements in pure nitrogen showed that the gas temperature can be reduced about 40The actual experiments are with Xe and Ar bands in the VUV and the results of radiation output under d.c. and pulsed operation for different pulse duration and repetition rates are presented. [1] A. El-Habachi, K.H. Schoenbach, Appl. Phys. Lett. 73(7), pp. 885-887 (1998) [2] U. Ernst, "Emissionsspektroskopische Charakterisierung von Hochdruck-Mikrohohlkathodenentladungen", Ph. D thesis, Univ. of Erlangen-Nuremberg, 2001 This work was supported by DFG under the contact FR 1273-1

  19. Shock propagation and attenuation in high-power excimer lasers

    NASA Astrophysics Data System (ADS)

    Holzwarth, Achim; Berger, Peter; Huegel, Helmut

    1993-05-01

    Theoretical and experimental investigations on the propagation, reflection, and attenuation of shock waves as they occur in excimer lasers have been performed. The numerical simulations have been carried out using a two-dimensional, unsteady finite difference scheme. The experimental setup is a piston driven shock tube with a rectangular cross section working in air at atmospheric pressure. The shocks were detected interferometrically as well as by means of pressure transducers. This shock tube allows us to investigate basic phenomena of shock diffraction which can be used to confirm the computational results in the range of weak shock waves. In particular, the influence of the shape of the wall contour on the reflection of shock waves has been investigated theoretically. The decay time of pressure and density perturbations differs for various wall configurations in such a way that short electrodes accelerate the attenuation as well as does a strong area increase in the vicinity of them. After each laser pulse there is a shock travelling into the laser channel. Experiments have been carried out on the reflection of this shock at a specially formed bend that is able to focus the shock into a muffling element.

  20. Excimer laser chemical ammonia patterning on PET film.

    PubMed

    Wu, G; Paz, M D; Chiussi, S; Serra, J; González, P; Wang, Y J; Leon, B

    2009-02-01

    Laser is a promising technique used for biopolymer surface modification with micro and/or nano features. In this work, a 193 nm excimer laser was used for poly (ethylene terephthalate) (PET) surfaces chemical patterning. The ablation threshold of the PET film used in the experiments was 62 mJ/cm(2) measured before surface modification. Surface chemical patterning was performed by irradiating PET film in a vacuum chamber filled with ammonia at the flux of 10, 15, 20, 25 ml/min. Roughness of the surface characterized by profilometry showed that there were no significant observed change after modification comparing original film. But the hydrophilicity of the surface increased after patterning and a minimum water contact angle was obtained at the gas flux of 20 ml/min. FT-IR/ATR results showed the distinct amino absorption bands presented at 3352 cm(-1)and 1613 cm(-1) after modification and XPS binding energies of C(1s) at 285.5 eV and N(1s) at 399.0 eV verified the existence of C-N bond formation on the PET film surface. Tof-SIMS ions mapping used to identify the amine containing fragments corroborates that amino grafting mainly happened inside the laser irradiation area of the PET surface. A hypothesized radical reaction mechanism proposes that the collision between radicals in ammonia and on the PET surface caused by the incident laser provokes the grafting of amino groups.

  1. Technique for cellular microsurgery using the 193-nm excimer laser.

    PubMed

    Palanker, D; Ohad, S; Lewis, A; Simon, A; Shenkar, J; Penchas, S; Laufer, N

    1991-01-01

    A new cell surgery technique has been developed to produce well-defined alterations in cells and tissue without detectable heating and/or other structural damage in the surroundings. The technique involves the use of an argon fluoride excimer laser, in the deep ultraviolet (UV) region of the spectrum at 193 nm, which is guided through a glass pipette filled with a positive air pressure. To demonstrate the method, holes were drilled in the zona pellucida of mouse oocytes. The diameter of the drilled hole was determined by the pipette tip size, and its depth by an energy emitted per pulse and number of pulses. Scanning electron microscopy of the drilled mouse oocytes showed uniform, round, well-circumscribed holes with sharp edges. Oocytes that had their zona pellucida drilled with this new method fertilized in vitro and developed to the blastocyst stage in a rate similar to that of control group. These results demonstrate the nonperturbing nature of this cold laser microsurgical procedure. In addition to the extension of our results for clinical in vitro fertilization purposes, such as enhancement of fertilization and embryo biopsy, there are wide-ranging possible uses of our method in fundamental and applied investigations that require submicron accuracy in cellular alteration.

  2. Lamp method and apparatus using multiple reflections

    DOEpatents

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

    1999-01-01

    A method wherein the light in a sulfur or selenium lamp is reflected through the fill a multiplicity of times to convert ultraviolet radiation to visible. A light emitting device comprised of an electrodeless envelope which bears a light reflecting covering around a first portion which does not crack due to differential thermal expansion and which has a second portion which comprises a light transmissive aperture.

  3. Lamp method and apparatus using multiple reflections

    DOEpatents

    MacLennan, D.A.; Turner, B.; Kipling, K.

    1999-05-11

    A method wherein the light in a sulfur or selenium lamp is reflected through the fill a multiplicity of times to convert ultraviolet radiation to visible is disclosed. A light emitting device comprised of an electrodeless envelope which bears a light reflecting covering around a first portion which does not crack due to differential thermal expansion and which has a second portion which comprises a light transmissive aperture. 20 figs.

  4. CALiPER Retail Lamps Study 3

    SciTech Connect

    none,

    2014-02-01

    This is a special CALiPER report on LED lamps available through the retail marketplace and targeted toward general consumers. It follows similar reports published in 2011 and 2012 (products purchased in 2010 and 2011), and is intended as a continuation that identifies long-term trends. For this report, products were selected to investigate specific hypotheses, rather than represent a sample of the increasingly large retail LED market.

  5. Raman lidar characterization using a reference lamp

    NASA Astrophysics Data System (ADS)

    Landulfo, Eduardo; da Costa, Renata F.; Rodrigues, Patricia F.; da Silva Lopes, Fábio J.

    2014-10-01

    The determination of the amount of water vapor in the atmosphere using lidar is a calibration dependent technique. Different collocated instruments are used for this purpose, like radiossoundings and microwave radiometers. When there are no collocated instruments available, an independente lamp mapping calibration technique can be used. Aiming to stabilish an independ technique for the calibration of the six channels Nd-YAG Raman lidar system located at the Center for Lasers and Applications (CLA), S˜ao Paulo, Brazil, an optical characterization of the system was first performed using a reference tungsten lamp. This characterization is useful to identify any possible distortions in the interference filters, telescope mirror and stray light contamination. In this paper we show three lamp mapping caracterizations (01/16/2014, 01/22/2014, 04/09/2014). The first day is used to demostrate how the tecnique is useful to detect stray light, the second one how it is sensible to the position of the filters and the third one demostrates a well optimized optical system.

  6. High output lamp with high brightness

    DOEpatents

    Kirkpatrick, Douglas A.; Bass, Gary K.; Copsey, Jesse F.; Garber, Jr., William E.; Kwong, Vincent H.; Levin, Izrail; MacLennan, Donald A.; Roy, Robert J.; Steiner, Paul E.; Tsai, Peter; Turner, Brian P.

    2002-01-01

    An ultra bright, low wattage inductively coupled electrodeless aperture lamp is powered by a solid state RF source in the range of several tens to several hundreds of watts at various frequencies in the range of 400 to 900 MHz. Numerous novel lamp circuits and components are disclosed including a wedding ring shaped coil having one axial and one radial lead, a high accuracy capacitor stack, a high thermal conductivity aperture cup and various other aperture bulb configurations, a coaxial capacitor arrangement, and an integrated coil and capacitor assembly. Numerous novel RF circuits are also disclosed including a high power oscillator circuit with reduced complexity resonant pole configuration, parallel RF power FET transistors with soft gate switching, a continuously variable frequency tuning circuit, a six port directional coupler, an impedance switching RF source, and an RF source with controlled frequency-load characteristics. Numerous novel RF control methods are disclosed including controlled adjustment of the operating frequency to find a resonant frequency and reduce reflected RF power, controlled switching of an impedance switched lamp system, active power control and active gate bias control.

  7. Fluorescent ballast and lamp disposal issues

    SciTech Connect

    Leishman, D.L.

    1996-12-01

    All around the world, governments, utility companies, and private businesses are attempting to reduce the amount of energy consumed. In the US alone, new economic strategies and programs are being created to facilitate this process. For instance, the recent enactment of the National Energy Policy Act, the Environmental Protection Agency`s (EPA) Green Lights Program, and a surge of utility involvement in Demand Side Management (DSM) Commercial/Industrial Direct Install and Rebate Programs. Many of these problems target commercial/industrial lighting system retrofits as one of the most cost effective avenues for reducing the consumption of energy. Due to this trend, hundreds of millions of lighting ballasts and lamps are being discarded. The benefits of these programs result in enormous reductions in fossil fuels (and subsequent carbon dioxide, sulfur dioxide, and nitrogen oxide emissions) required to generate the displaced electricity. Throughout the US, however, there is an increasing concern for the environmental impacts surrounding the accelerated disposal of both lighting ballasts and lamps. Regulations initially established were for a one by one, retirement (failure) process rather than promoted obsolescence and forced retirement of lamp groups or entire systems (truckloads of old technologies). Recognizing this trend and the potential negative environmental effects, federal, state, and local regulators are reevaluating the impacts and are being asked to promulgate policies to specifically address this situation.

  8. Excimer laser-induced formation of metallic microstructures by electroless copper plating

    NASA Astrophysics Data System (ADS)

    Yang, H.; Pan, C.-T.

    2002-03-01

    Micro-patterns created by the excimer laser and activated by reactants for electroless copper plating are described in this paper. The generated micro-patterns are transformed into copper patterns on the substrate and copper microstructures are formed. This method simplifies the manufacturing process of making circuits on boards compared with the conventional lithography process of forming copper patterns on the substrate. Micro-patterns generated by the excimer laser cause changes of surface electric properties and activation selectively. A chemical reaction through these activated areas may deposit metal, such as copper. The KrF excimer laser not only provides simple and fast machining patterns, but also uses its high-energy density to drill holes and circuits directly. Palladium ions are added as mediators in the electroless plating solution to enable a continuous electroless copper deposition. According to the experiment of excimer laser-assisted electroless copper plating, the procedures of pretreatment and post-cleaning are the key factors that resulted in excellent selective plating. The samples were pretreated by sodium dodecyl sulfate (SDS) and post-cleaned by acetone and diluted nitric acid resulting in distinct micro-patterns. The deposition area is confined to the excimer laser-ablated portion resulting in good selective plating.

  9. Phasor Representation of Monomer-Excimer Kinetics: General Results and Application to Pyrene.

    PubMed

    Martelo, Liliana; Fedorov, Alexander; Berberan-Santos, Mário N

    2015-12-03

    Phasor plots of the fluorescence intensity decay (plots of the Fourier sine transform versus the Fourier cosine transform, for one or several angular frequencies) are being increasingly used in studies of homogeneous and heterogeneous systems. In this work, the phasor approach is applied to monomer-excimer kinetics. The results obtained allow a clear visualization of the information contained in the decays. The monomer phasor falls inside the universal circle, whereas the excimer phasor lies outside it, but within the double-exponential outer boundary curve. The monomer and excimer phasors, along with those corresponding to the two exponential components of the decays, fall on a common straight line and obey the generalized lever rule. The clockwise trajectories described by both phasors upon monomer concentration increase are identified. The phasor approach allows discussing in a single graphic not only the effect of concentration but also that of rate constants, including the evolution from irreversible kinetics to fast excited-state equilibrium upon a temperature increase. The obtained results are applied to the fluorescence decays of pyrene monomer and excimer in methylcyclohexane at room temperature. A straightforward method of monomer-excimer lifetime data analysis based on linear plots is also introduced.

  10. Polycation-induced benzoperylene probe excimer formation and the ratiometric detection of heparin and heparinase.

    PubMed

    Yang, Meiding; Chen, Jian; Zhou, Huipeng; Li, Wenying; Wang, Yan; Li, Juanmin; Zhang, Cuiyun; Zhou, Chuibei; Yu, Cong

    2016-01-15

    A benzoperylene probe excimer emission in an aqueous buffer solution is observed for the first time, and a novel ratiometric fluorescence method based on the probe excimer emission for the sensitive detection of heparin and heparinase is demonstrated. A negatively charged benzoperylene derivative, 6-(benzo[ghi]perylene-1,2-dicarboxylic imide-yl)hexanoic acid (BPDI), was employed. A polycation, poly(diallyldimethylammonium) chloride (poly-DDA), could induce aggregation of BPDI through noncovalent interactions. A decrease of BPDI monomer emission and a simultaneous increase of BPDI excimer emission were observed. Upon the addition of heparin, the strong binding between heparin and poly-DDA caused release of BPDI monomer molecules, and an excimer-monomer emission signal transition was detected. However, after the enzymatic hydrolysis of heparin by heparinase, heparin was hydrolyzed into small fragments, which weakened the competitive binding of heparin to poly-DDA. Poly-DDA induced aggregation of BPDI, and a monomer-excimer emission signal transition was detected. Our assay is simple, rapid, inexpensive, sensitive and selective, which could facilitate the heparin and heparinase related biochemical and biomedical research.

  11. Max Tech and Beyond: High-Intensity Discharge Lamps

    SciTech Connect

    Scholand, Michael

    2012-04-01

    High-intensity discharge (HID) lamps are most often found in industrial and commercial applications, and are the light source of choice in street and area lighting, and sports stadium illumination. HID lamps are produced in three types - mercury vapor (MV), high pressure sodium (HPS) and metal halide (MH). Of these, MV and MH are considered white-light sources (although the MV exhibits poor color rendering) and HPS produces a yellow-orange color light. A fourth lamp, low-pressure sodium (LPS), is not a HID lamp by definition, but it is used in similar applications and thus is often grouped with HID lamps. With the notable exception of MV which is comparatively inefficient and in decline in the US from both a sales and installed stock point of view; HPS, LPS and MH all have efficacies over 100 lumens per watt. The figure below presents the efficacy trends over time for commercially available HID lamps and LPS, starting with MV and LPS in 1930's followed by the development of HPS and MH in the 1960's. In HID lamps, light is generated by creating an electric arc between two electrodes in an arc tube. The particles in the arc are partially ionized, making them electrically conductive, and a light-emitting 'plasma' is created. This arc occurs within the arc tube, which for most HID lamps is enclosed within an evacuated outer bulb that thermally isolates and protects the hot arc tube from the surroundings. Unlike a fluorescent lamp that produces visible light through down-converting UV light with phosphors, the arc itself is the light source in an HID lamp, emitting visible radiation that is characteristic of the elements present in the plasma. Thus, the mixture of elements included in the arc tube is one critical factor determining the quality of the light emitted from the lamp, including its correlated color temperature (CCT) and color rendering index (CRI). Similar to fluorescent lamps, HID lamps require a ballast to start and maintain stable operating conditions, and

  12. Disturbed Cholesterol Traffic but Normal Proteolytic Function in LAMP-1/LAMP-2 Double-deficient FibroblastsD⃞

    PubMed Central

    Eskelinen, Eeva-Liisa; Schmidt, Christine Katrin; Neu, Silja; Willenborg, Marion; Fuertes, Graciela; Salvador, Natalia; Tanaka, Yoshitaka; Lüllmann-Rauch, Renate; Hartmann, Dieter; Heeren, Jörg; von Figura, Kurt; Knecht, Erwin; Saftig, Paul

    2004-01-01

    Mice double deficient in LAMP-1 and -2 were generated. The embryos died between embryonic days 14.5 and 16.5. An accumulation of autophagic vacuoles was detected in many tissues including endothelial cells and Schwann cells. Fibroblast cell lines derived from the double-deficient embryos accumulated autophagic vacuoles and the autophagy protein LC3II after amino acid starvation. Lysosomal vesicles were larger and more peripherally distributed and showed a lower specific density in Percoll gradients in double deficient when compared with control cells. Lysosomal enzyme activities, cathepsin D processing and mannose-6-phosphate receptor expression levels were not affected by the deficiency of both LAMPs. Surprisingly, LAMP-1 and -2 deficiencies did not affect long-lived protein degradation rates, including proteolysis due to chaperone-mediated autophagy. The LAMP-1/2 double-deficient cells and, to a lesser extent, LAMP-2 single-deficient cells showed an accumulation of unesterified cholesterol in endo/lysosomal, rab7, and NPC1 positive compartments as well as reduced amounts of lipid droplets. The cholesterol accumulation in LAMP-1/2 double-deficient cells could be rescued by overexpression of murine LAMP-2a, but not by LAMP-1, highlighting the more prominent role of LAMP-2. Taken together these findings indicate partially overlapping functions for LAMP-1 and -2 in lysosome biogenesis, autophagy, and cholesterol homeostasis. PMID:15121881

  13. Calorimetric Observation of Single {He}_2^* Excimers in a 100-mK He Bath

    NASA Astrophysics Data System (ADS)

    Carter, F. W.; Hertel, S. A.; Rooks, M. J.; McClintock, P. V. E.; McKinsey, D. N.; Prober, D. E.

    2017-02-01

    We report the first calorimetric detection of individual {He}_2^* excimers within a bath of superfluid ^4{He}. The detector used in this work is a single superconducting titanium transition edge sensor (TES) with an energy resolution of {˜ }1 {eV}, immersed directly in the helium bath. {He}_2^* excimers are produced in the surrounding bath using an external gamma-ray source. These excimers exist either as short-lived singlet or long-lived triplet states. We demonstrate detection (and discrimination) of both states: In the singlet case the calorimeter records the absorption of a prompt {≈ }15 {eV} photon, and in the triplet case the calorimeter records a direct interaction of the molecule with the TES surface, which deposits a distinct fraction of the {≈ }15 {eV}, released upon decay, into the surface. We also briefly discuss the detector fabrication and characterization.

  14. Sn(II) induced concentration dependent dynamic to static excimer conversion of a conjugated naphthalene derivative.

    PubMed

    Adhikari, Susanta; Mandal, Sandip; Ghosh, Avijit; Guria, Subhajit; Das, Debasis

    2015-08-28

    The X-ray structurally characterized naphthalene appended diformyl-p-cresol derivative () selectively detects Sn(2+) by both colorimetric and fluorescence methods. In the presence of Sn(2+), exhibits a monomer emission at 420 nm along with a strong red excimer emission at 582 nm in acetonitrile. The excimer formation highly depends on Sn(2+) concentration. The dynamic excimer, observed with up to 2.5 equivalents of Sn(2+), gradually converts to a static form above 2.5 equivalents of Sn(2+). Moreover, in a different solvent media, viz. in aqueous methanol, can also detect Al(3+) through the generation of intense green fluorescence. The photophysical interactions are rationalized by (1)H NMR, mass spectra, steady state and lifetime fluorescence measurements. DFT studies support the experimental findings.

  15. Label-free detection of polynucleotide single-base mismatch via pyrene probe excimer emission

    NASA Astrophysics Data System (ADS)

    Tang, Dan; Lu, Ping; Liao, Dongli; Yang, Xiangyu; Zhang, Yujing; Yu, Cong

    2011-02-01

    The pyrene probe and pyrene-labeled oligonucleotides (ODNs) probe are expected to be candidates as fluorescent probe for DNA assay. In particular, label-free detection is a very hot because of its simpleness, speediness and cheapness. Herein, we have investigated the use of a pyrenylakylammonium salt, a novel fluorescent probe for the detection of one single nucleotide polymorphism (SNP) in double stranded DNA. After S1 nuclease digestion, the pyrene probes bind electrostatically to the perfect complement DNA and emit a strong excimer emission. However, treatment of the non-complementary DNA with S1 nuclease caused nucleotide fragments of less than 5 bases, which could not induce excimer emission. By comparing ratio of excimer to monomer fluorescence between normal and mutant DNA after S1 nuclease digestion, One-base mutation in DNA was detected easily. This new method may be applied to the detection of SNP.

  16. Rational design and studies of excimer forming novel dual probes to target RNA.

    PubMed

    Krasheninina, O A; Lomzov, A A; Fishman, V S; Novopashina, D S; Venyaminova, A G

    2017-04-01

    In this paper, we report structure-based rational design and physico-chemical and biological studies of novel pyrene excimer forming dual probes for visualization of intracellular RNAs. Herein, the probes based on 2'-O-methyl RNA with linkers of different structure and length between pyrene moiety and ribose are studied with respect to their hybridization and spectral properties. We found optimal linkers that provide more intense excimer emission (at ∼480nm) of RNA-bound probes; particularly, the length of the linker arm of the 3'-component of dual probes plays a key role in formation of pyrene excimer. Calculated molecular dynamics trajectories and probability distributions of pyrene-pyrene dimer formation upon hybridization of the dual probes with RNA target are in agreement with the obtained fluorescence spectroscopy data for the corresponding duplexes. Our study demonstrates the excellent binding properties of new dual probes to structured RNA and their feasibility for the visualization of intracellular RNA targets.

  17. Excimer lasers for superhigh NA 193-nm lithography

    NASA Astrophysics Data System (ADS)

    Paetzel, Rainer; Albrecht, Hans S.; Lokai, Peter; Zschocke, Wolfgang; Schmidt, Thomas; Bragin, Igor; Schroeder, Thomas; Reusch, Christian; Spratte, Stefan

    2003-06-01

    Excimer lasers are widely used as the light source for microlithography scanners. The volume shipment of scanner systems using 193nm is projected to begin in year 2003. Such tools will directly start with super high numerical aperture (NA) in order to take full advantage of the 193nm wavelength over the advanced 248nm systems. Reliable high repetition rate laser light sources enabling high illumination power and wafer throughput are one of the fundamental prerequisites. In addition these light sources must support a very high NA imaging lens of more than 0.8 which determines the output spectrum of the laser to be less than 0.30 pm FWHM. In this paper we report on our recent progress in the development of high repetition rate ultra-narrow band lasers for high NA 193nm microlithography scanners. The laser, NovaLine A4003, is based on a Single Oscillator Ultral Line-narrowed (SOUL) design which yields a bandwidth of less than 0.30pm FWHM. The SOUL laser enables superior optical performance without adding complexity or cost up to the 4 kHz maximum repetition rate. The A4003's high precision line-narrowing optics used in combination with the high repetition rate of 4 kHz yields an output power of 20 W at an extremely narrow spectral bandwidth of less than 0.30 pm FWHM and highest spectral purity of less than 0.75 pm for the 95% energy content. We present performance and reliability data and discuss the key laser parameters. Improvements in the laser-internal metrology and faster regulation control result in better energy stability and improved overall operation behavior. The design considerations for line narrowing and stable laser operation at high repetition rates are discussed.

  18. UV excimer laser photochemistry of hybrid organometallic compounds of gallium

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Cleaver, W. M.; Stuke, M.; Barron, A. R.

    1992-09-01

    The gas phase ultraviolet (UV) excimer laser induced photolysis of the gallium-alkyls Ga( t-C4H9) n - (CH3)3- n ( n=0, 1, 2, 3) was studied, using photolysis wavelengths of 308, 248, and 193 nm. The photofragments Ga, GaH, and GaCH3 were detected by laser ionization time-of-flight mass spectroscopy, while the hydrocarbon products CH4, C2H6, HC(CH3)3 and H2C=C(CH3)2 were identified using Fourier transform infrared (FTIR) spectroscopy. The formation of the GaH photofragment, and a high olefin-to-alkane product ratio, for Ga( t-C4H9)2(CH3) and Ga( t-C4H9)3 are interpreted to indicate a β-hydrogen elimination process. However, β-hydrogen elimination only occurs after fission of the weakest Ga-C bond, thus no β-hydride elimination is observed for Ga( t-C4H9)(CH3)2. Detection of C2H6 for Ga(CH3)3 and Ga( t-C4H9)(CH3)2, but not for Ga( t-C4H9)2(CH3), shows that under our experimental conditions the formation of ethane is as a result of the reductive elimination of the methyl groups, and is not due to the recombination of two free methyl radicals.

  19. Advanced excimer laser technologies enable green semiconductor manufacturing

    NASA Astrophysics Data System (ADS)

    Fukuda, Hitomi; Yoo, Youngsun; Minegishi, Yuji; Hisanaga, Naoto; Enami, Tatsuo

    2014-03-01

    "Green" has fast become an important and pervasive topic throughout many industries worldwide. Many companies, especially in the manufacturing industries, have taken steps to integrate green initiatives into their high-level corporate strategies. Governments have also been active in implementing various initiatives designed to increase corporate responsibility and accountability towards environmental issues. In the semiconductor manufacturing industry, there are growing concerns over future environmental impact as enormous fabs expand and new generation of equipments become larger and more powerful. To address these concerns, Gigaphoton has implemented various green initiatives for many years under the EcoPhoton™ program. The objective of this program is to drive innovations in technology and services that enable manufacturers to significantly reduce both the financial and environmental "green cost" of laser operations in high-volume manufacturing environment (HVM) - primarily focusing on electricity, gas and heat management costs. One example of such innovation is Gigaphoton's Injection-Lock system, which reduces electricity and gas utilization costs of the laser by up to 50%. Furthermore, to support the industry's transition from 300mm to the next generation 450mm wafers, technologies are being developed to create lasers that offer double the output power from 60W to 120W, but reducing electricity and gas consumption by another 50%. This means that the efficiency of lasers can be improve by up to 4 times in 450mm wafer production environments. Other future innovations include the introduction of totally Heliumfree Excimer lasers that utilize Nitrogen gas as its replacement for optical module purging. This paper discusses these and other innovations by Gigaphoton to enable green manufacturing.

  20. Philips' 2nd generation Novallure LED candle lamp

    NASA Astrophysics Data System (ADS)

    Li, Yun; Pei, Zhigang; Yuan, Chuan; Jiang, Tan; Lu, Zhengsong; Wang, Yuqian; Duan, Xiaoqing; Xiong, Yan; Zhong, Hong; Liu, Ye

    2010-08-01

    Finding an energy efficient replacement of incandescent candle lamp has been a technical challenge. Compact fluorescent lamps, for example, can be miniaturized to fit the form factor of a candle lamp but they fail to reproduce its "sparkle" effect. Empowered by solid state lighting technology along with original optical design, Philips has successfully developed LED-powered candle lamps "Novallure" with great energy savings (2W power consumption with lumen output of 55 lumen) and the "butterfly" radiation pattern that mimics the sparkle effect from an incandescent candle lamp. With new high performance LED packages, novel under-cut prismatic optics and state-of-the-art electronic driver solution and thermal solution, we have developed a 2nd generation Novallure with breakthrough performance: a dimmable 2700K 136 lumen LED candle lamp with CRI 90.

  1. Excimer laser debridement of necrotic erosions of skin without collateral damage

    NASA Astrophysics Data System (ADS)

    Wynne, James J.; Felsenstein, Jerome M.; Trzcinski, Robert; Zupanski-Nielsen, Donna; Connors, Daniel P.

    2011-07-01

    Pulsed ArF excimer laser radiation at 6.4 eV, at fluence exceeding the ablation threshold, will debride burn eschar and other dry necrotic erosions of the skin. Debridement will cease when sufficiently moist viable tissue is exposed, due to absorption by aqueous chloride ions (Cl-) through the non-thermal process of electron photodetachment, thereby inhibiting collateral damage to the viable tissue. ArF excimer laser radiation debrides/ablates ~1 micron of tissue with each pulse. While this provides great precision in controlling the depth of debridement, the process is relatively time-consuming. In contrast, XeCl excimer laser radiation debrides ~8 microns of tissue with each pulse. However the 4.0 eV photon energy of the XeCl excimer laser is insufficient to photodetach an electron from a Cl- ion, so blood or saline will not inhibit debridement. Consequently, a practical laser debridement system should incorporate both lasers, used in sequence. First, the XeCl excimer laser would be used for accelerated debridement. When the necrotic tissue is thinned to a predetermined thickness, the ArF excimer laser would be used for very precise and well-controlled debridement, removing ultra-thin layers of material with each pulse. Clearly, the use of the ArF laser is very desirable when debriding very close to the interface between necrotic tissue and viable tissue, where the overall speed of debridement need not be so rapid and collateral damage to viable tissue is undesirable. Such tissue will be sterile and ready for further treatment, such as a wound dressing and/or a skin graft.

  2. Excimer lasers. (Latest citations from the US Patent bibliographic file with exemplary claims). Published Search

    SciTech Connect

    1995-01-01

    The bibliography contains citations of selected patents concerning the design and development of excimer laser devices, apparatus, and systems for use in industrial and medical applications. Citations discuss ablation and lithography technology, compact excimer lasers, laser gas purification and recycling, microwave and discharge excited lasers, and rare gas halides. Applications are considered, including metallization and patterning, manufacturing of ophthalmic lenses, profiling of optical surfaces, treatment of engine parts, prosthetic surgery, and corneal ablation. (Contains a minimum of 106 citations and includes a subject term index and title list.)

  3. Excimer lasers. (Latest citations from the US Patent Bibliographic file with exemplary claims). Published Search

    SciTech Connect

    1996-01-01

    The bibliography contains citations of selected patents concerning the design and development of excimer laser devices, apparatus, and systems for use in industrial and medical applications. Citations discuss ablation and lithography technology, compact excimer lasers, laser gas purification and recycling, microwave and discharge excited lasers, and rare gas halides. Applications are considered, including metallization and patterning, manufacturing of ophthalmic lenses, profiling of optical surfaces, treatment of engine parts, prosthetic surgery, and corneal ablation. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  4. Fluorescent lamp unit with magnetic field generating means

    DOEpatents

    Grossman, M.W.; George, W.A.

    1989-08-08

    A fluorescent lamp unit having a magnetic field generating means for improving the performance of the fluorescent lamp is disclosed. In a preferred embodiment the fluorescent lamp comprises four longitudinally extending leg portions disposed in substantially quadrangular columnar array and joined by three generally U-shaped portions disposed in different planes. In another embodiment of the invention the magnetic field generating means comprises a plurality of permanent magnets secured together to form a single columnar structure disposed within a centrally located region defined by the shape of lamp envelope. 4 figs.

  5. The effectiveness of side marker lamps: an experimental study.

    PubMed

    Theeuwes, J; Alferdinck, J W

    1997-03-01

    The present experiment investigated the effect of small amber lamps mounted near the front and rear on each side of a passenger car-so called side marker lamps-on visual detection and recognition of passenger cars in complex nighttime environments. It was determined whether cars equipped with side marker lamps are detected and recognized earlier and more accurately than cars without side marker lamps. Subjects were presented with slides of natural nighttime scenes in which a car, either with or without side marker lamps, viewed from its side, approaching from a side street, was either present or not. Subjects determined as fast as possible whether a car was present or not. Reaction time measures (speed and accuracy) indicated that both under clear and fog visibility conditions, a car equipped with side marker lamps was detected and recognized earlier and more accurately than a car without side marker lamps. The results indicate that side marker lamps increase both lateral conspicuity and recognizability suggesting that side marker lamps may be effective in reducing the number of nighttime angle collisions.

  6. Heat transfer assembly for a fluorescent lamp and fixture

    DOEpatents

    Siminovitch, M.J.; Rubenstein, F.M.; Whitman, R.E.

    1992-12-29

    In a lighting fixture including a lamp and a housing, a heat transfer structure is disclosed for reducing the minimum lamp wall temperature of a fluorescent light bulb. The heat transfer structure, constructed of thermally conductive material, extends from inside the housing to outside the housing, transferring heat energy generated from a fluorescent light bulb to outside the housing where the heat energy is dissipated to the ambient air outside the housing. Also disclosed is a method for reducing minimum lamp wall temperatures. Further disclosed is an improved lighting fixture including a lamp, a housing and the aforementioned heat transfer structure. 11 figs.

  7. Heat transfer assembly for a fluorescent lamp and fixture

    DOEpatents

    Siminovitch, Michael J.; Rubenstein, Francis M.; Whitman, Richard E.

    1992-01-01

    In a lighting fixture including a lamp and a housing, a heat transfer structure is disclosed for reducing the minimum lamp wall temperature of a fluorescent light bulb. The heat transfer structure, constructed of thermally conductive material, extends from inside the housing to outside the housing, transferring heat energy generated from a fluorescent light bulb to outside the housing where the heat energy is dissipated to the ambient air outside the housing. Also disclosed is a method for reducing minimum lamp wall temperatures. Further disclosed is an improved lighting fixture including a lamp, a housing and the aforementioned heat transfer structure.

  8. Fluorescent lamp unit with magnetic field generating means

    DOEpatents

    Grossman, Mark W.; George, William A.

    1989-01-01

    A fluorescent lamp unit having a magnetic field generating means for improving the performance of the fluorescent lamp is disclosed. In a preferred embodiment the fluorescent lamp comprises four longitudinally extending leg portions disposed in substantially quadrangular columnar array and joined by three generally U-shaped portions disposed in different planes. In another embodiment of the invention the magnetic field generating means comprises a plurality of permanent magnets secured together to form a single columnar structure disposed within a centrally located region defined by the shape of lamp envelope.

  9. Hazards from High Intensity Lamps and Arcs

    NASA Technical Reports Server (NTRS)

    Sliney, D. H.

    1970-01-01

    The principal occupational health problem generally associated with high intensity arc lamps results from exposure of the eye and skin to ultraviolet radiation. Occasionally, the chorioretinal burns are of concern. The eye is generally more susceptible than the skin to injury from high intensity optical radiation sources whether ultraviolet, visible or infrared. Recent developments in technology have shown that some high intensity optical radiation sources which have output parameters greatly different from those encountered in the natural environment present a serious chorioretinal burn hazard.

  10. Compact microwave lamp having a tuning block and a dielectric located in a lamp cavity

    DOEpatents

    Simpson, James E.

    2000-01-01

    A microwave lamp having a compact structure utilizing a coupling slot which has a dielectric member extending therethrough and a tuning block adjoining the coupling slot. A non-conventional waveguide is used which has about the width of a WR-284 waveguide and about the length of a WR-340 waveguide.

  11. Compact microwave lamp having a tuning block and a dielectric located in a lamp cavity

    SciTech Connect

    Simpson, J.E.

    2000-02-29

    A microwave lamp having a compact structure utilizing a coupling slot which has a dielectric member extending there through and a tuning block adjoining the coupling slot. A non-conventional waveguide is used which has about the width of a WR-284 waveguide and about the length of a WR-340 waveguide.

  12. RF driven sulfur lamp having driving electrodes arranged to cool the lamp

    DOEpatents

    Gabor, George; Orr, Thomas Robert; Greene, Charles Maurice; Crawford, Douglas Gordon; Berman, Samuel Maurice

    1998-01-01

    A high intensity discharge lamp without mercury is disclosed radiating a selected spectrum of which can be almost entirely in the visible range from an envelope that contains a sulfur containing substance. The lamp utilizes a signal source that generates an excitation signal that is externally coupled to the exterior surface of the envelope to excite the enclosed sulfur containing substance. Various embodiments of the lamp use electrodes adjacent the envelope to couple the excitation signal thereto with the face of the electrodes shaped to complement the shape of the exterior surface of the envelope. Two shapes discussed are spherical and cylindrical. To minimize filamentary discharges each envelope may include an elongated stem affixed to the exterior thereof whereby a rotational subsystem spins the envelope. In yet another embodiment the envelope has a Dewar configuration with two electrodes, one positioned near the external curved side surface of the body, and a second to the inner surface of the hole through the envelope. Further, the envelope may contain a backfill of a selected inert gas to assist in the excitation of lamp with that backfill at a pressure of less than 1 atmosphere, wherein the backfill pressure is directly related to the increase or decrease of peak output and inversely related to the increase and decrease of the emitted spectrum from the envelope. The emitting fill can be less than 6 mg/cc, or at least 2 mg/cc of the envelope of a sulfur containing substance.

  13. RF driven sulfur lamp having driving electrodes arranged to cool the lamp

    DOEpatents

    Gabor, G.; Orr, T.R.; Greene, C.M.; Crawford, D.G.; Berman, S.M.

    1998-10-20

    A high intensity discharge lamp without mercury is disclosed radiating a selected spectrum of which can be almost entirely in the visible range from an envelope that contains a sulfur containing substance. The lamp utilizes a signal source that generates an excitation signal that is externally coupled to the exterior surface of the envelope to excite the enclosed sulfur containing substance. Various embodiments of the lamp use electrodes adjacent the envelope to couple the excitation signal thereto with the face of the electrodes shaped to complement the shape of the exterior surface of the envelope. Two shapes discussed are spherical and cylindrical. To minimize filamentary discharges each envelope may include an elongated stem affixed to the exterior thereof whereby a rotational subsystem spins the envelope. In yet another embodiment the envelope has a Dewar configuration with two electrodes, one positioned near the external curved side surface of the body, and a second to the inner surface of the hole through the envelope. Further, the envelope may contain a backfill of a selected inert gas to assist in the excitation of lamp with that backfill at a pressure of less than 1 atmosphere, wherein the backfill pressure is directly related to the increase or decrease of peak output and inversely related to the increase and decrease of the emitted spectrum from the envelope. The emitting fill can be less than 6 mg/cc, or at least 2 mg/cc of the envelope of a sulfur containing substance. 17 figs.

  14. Moving Forward: College and Career Transitions of LAMP Graduates. Findings from the LAMP Longitudinal Study.

    ERIC Educational Resources Information Center

    MacAllum, Keith; Yoder, Karla; Kim, Scott; Bozick, Robert

    A longitudinal study examined the college and career transitions of graduates of the Lansing Area Manufacturing Partnership (LAMP) program, which is a school-to-career (STC) program sponsored by the United Auto Workers, General Motors Corporation, and Michigan's Ingham County Intermediate School District. The progress of three cohorts of LAMP…

  15. LAMP Whys? LAMP Wise! A Practical Guide to the Lansing Area Manufacturing Partnership.

    ERIC Educational Resources Information Center

    MacAllum, Keith; McDonald, Deanne; Johnson, Amy Bell

    This document profiles the Lansing Area Manufacturing Partnership (LAMP), which is a model school-to-career initiative featuring an innovative integrated, employer-driven curriculum that was designed, developed, and implemented through the joint efforts of the Ingham Intermediate School District in Lansing, Michigan, the United Auto Workers (UAW),…

  16. 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.

  17. [Near infrared light irradiator using halogen lamp].

    PubMed

    Ide, Yasuo

    2012-07-01

    The practical electric light bulb was invented by Thomas Alva Edison in 1879. Halogen lamp is the toughest and brightest electric light bulb. With light filter, it is used as a source of near infrared light. Super Lizer and Alphabeam are made as near infrared light irradiator using halogen lamp. The light emmited by Super Lizer is linear polarized near infrared light. The wave length is from 600 to 1,600 nm and strongest at about 1,000 nm. Concerning Super Lizer, there is evidence of analgesic effects and normalization of the sympathetic nervous system. Super Lizer has four types of probes. SG type is used for stellate ganglion irradiation. B type is used for narrow area irradiation. C and D types are for broad area irradiation. The output of Alphabeam is not polarized. The wave length is from 700 to 1,600 nm and the strongest length is about 1,000nm. Standard attachment is used for spot irradiation. Small attachment is used for stellate ganglion irradiation. Wide attachment is used for broad area irradiation. The effects of Alphabeam are thought to be similar to that of Super Lizer.

  18. 78 FR 14357 - Certain Compact Fluorescent Reflector Lamps, Products Containing Same and Components Thereof...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-05

    ... COMMISSION Certain Compact Fluorescent Reflector Lamps, Products Containing Same and Components Thereof... importation of certain compact fluorescent reflector lamps, products containing same and components thereof by... importation of certain compact fluorescent reflector lamps, products containing same and components thereof...

  19. Development of the pellicle for KrF excimer laser photolithography

    NASA Astrophysics Data System (ADS)

    Shirasaki, Toru; Kawakami, S.; Hamada, Y.; Nagata, Y.; Kashida, Meguru; Kubota, Yoshihiro

    1994-11-01

    This paper describes development of the pellicle for KrF excimer laser photolithography. The components of KrF excimer pellicle should have high light resistance. Our pellicle membrane consists of amorphous perfluoropolymer. Since this material provides that scattering and absorption of light at deep-UV wavelength region are very small, transmissivity is high at that wavelength and light resistance is strong against KrF excimer laser. Membrane bond and reticle adhesive consist of silicone resin so that the light resistance of them is high. And the bond strength of our pellicle is very high despite the use of fluoro-polymer membrane. This is because the bond consists of silicone resin which contains fluorocarbon-group. Strict particle suppression is required for the excimer pellicle. We have covered the frame with UV resistant fluoropolymer for the purpose to reduce the possibility of particle generation. This treatment has suppressed the particle generation during transportation. Membrane cutting has been achieved by melt-cutting method. The prominency of this method is melting the membrane with heat and cutting it with no contact with pellicle frame, so that the membrane edge becomes smooth and pellicle frame has not been damaged.

  20. Excimer laser coronary atherectomy in septal collaterals during retrograde recanalization of a chronic total occlusion

    PubMed Central

    Ohlow, Marc-Alexander; Lotze, Ullrich; Lauer, Bernward

    2011-01-01

    Management of chronic total occlusions has been refined through the development of a retrograde approach via collateral pathways. We describe here the use of excimer laser coronary atherectomy in the septal collaterals. This appraoch was not yet described in the literature. PMID:22355487

  1. Fluorescent lamp with static magnetic field generating means

    DOEpatents

    Moskowitz, P.E.; Maya, J.

    1987-09-08

    A fluorescent lamp wherein magnetic field generating means (e.g., permanent magnets) are utilized to generate a static magnetic field across the respective electrode structures of the lamp such that maximum field strength is located at the electrode's filament. An increase in efficacy during operation has been observed. 2 figs.

  2. Fluorescent lamp with static magnetic field generating means

    DOEpatents

    Moskowitz, Philip E.; Maya, Jakob

    1987-01-01

    A fluorescent lamp wherein magnetic field generating means (e.g., permanent magnets) are utilized to generate a static magnetic field across the respective electrode structures of the lamp such that maximum field strength is located at the electrode's filament. An increase in efficacy during operation has been observed.

  3. Convection venting lensed reflector-type compact fluorescent lamp system

    DOEpatents

    Pelton, Bruce A.; Siminovitch, Michael

    1997-01-01

    Disclosed herein is a fluorescent lamp housing assembly capable of providing convection cooling to the lamp and the ballast. The lens of the present invention includes two distinct portions, a central portion and an apertured portion. The housing assembly further includes apertures so that air mass is able to freely move up through the assembly and out ventilation apertures.

  4. Convection venting lensed reflector-type compact fluorescent lamp system

    DOEpatents

    Pelton, B.A.; Siminovitch, M.

    1997-07-29

    Disclosed herein is a fluorescent lamp housing assembly capable of providing convection cooling to the lamp and the ballast. The lens of the present invention includes two distinct portions, a central portion and an apertured portion. The housing assembly further includes apertures so that air mass is able to freely move up through the assembly and out ventilation apertures. 12 figs.

  5. Modelling of Ar/Hg Induction Lamps with PLASIMO

    NASA Astrophysics Data System (ADS)

    van Dijk, J.; Janssen, G. M.; van der Mullen, J. A. M.

    1998-10-01

    In the last years various induction lamps have been announced by the major lighting companies. Examples are the Philips QL lamp, Osram's Endura and GE's Genura. In order to improve our understanding of such light sources some modelling has been done with the plasma simulation toolkit

  6. High-definition slit-lamp video camera system.

    PubMed

    Yamamoto, Satoru; Manabe, Noriyoshi; Yamamoto, Kenji

    2010-01-01

    Using a high-definition video camera for slit-lamp examination is now possible with the assistance of an adaptor. The authors describe the easy manipulation, convenience of use, and performance of a high-definition slit-lamp video camera system and provide images of eyes that were obtained using the system.

  7. Reaction times to neon, LED, and fast incandescent brake lamps.

    PubMed

    Sivak, M; Flannagan, M J; Sato, T; Traube, E C; Aoki, M

    1994-06-01

    Standard incandescent brake lamps have a relatively slow rise time. It takes approximately a quarter of a second for them to reach 90% of asymptotic light output, causing potential delays in responses by following drivers. The present study evaluated reaction times to brake signals from standard incandescent brake lamps and from three alternative brake lamps with substantially faster rise times: neon, LED, and fast incandescent. The study, performed in a laboratory, simulated a daytime driving condition. The subject's task was to respond as quickly as possible to the onset of either of two brake lamps in the visual periphery, while engaged in a central tracking task. Brake signals were presented at two levels of luminous intensity. The results showed that reaction times to the alternative brake lamps were faster than to the standard incandescent lamp, with the advantage averaging 166 ms for the LED and neon lamps, and 135 ms for the fast incandescent lamp. A reduction of the signals' luminous intensity from 42 cd to 5 cd increased the reaction time by 84 ms.

  8. 49 CFR 393.11 - Lamps and reflective devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... reflective devices. (a)(1) Lamps and reflex reflectors. Table 1 specifies the requirements for lamps... reflex reflectors listed in Table 1 if— (i) The conspicuity material is placed at the locations where reflex reflectors are required by Table 1; and (ii) The conspicuity material when installed on the...

  9. 49 CFR 393.11 - Lamps and reflective devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... reflective devices. (a)(1) Lamps and reflex reflectors. Table 1 specifies the requirements for lamps... reflex reflectors listed in Table 1 if— (i) The conspicuity material is placed at the locations where reflex reflectors are required by Table 1; and (ii) The conspicuity material when installed on the...

  10. 49 CFR 393.11 - Lamps and reflective devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... reflective devices. (a)(1) Lamps and reflex reflectors. Table 1 specifies the requirements for lamps... reflex reflectors listed in Table 1 if— (i) The conspicuity material is placed at the locations where reflex reflectors are required by Table 1; and (ii) The conspicuity material when installed on the...

  11. 49 CFR 393.11 - Lamps and reflective devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... reflective devices. (a)(1) Lamps and reflex reflectors. Table 1 specifies the requirements for lamps... reflex reflectors listed in Table 1 if— (i) The conspicuity material is placed at the locations where reflex reflectors are required by Table 1; and (ii) The conspicuity material when installed on the...

  12. 49 CFR 393.11 - Lamps and reflective devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... reflective devices. (a)(1) Lamps and reflex reflectors. Table 1 specifies the requirements for lamps... reflex reflectors listed in Table 1 if— (i) The conspicuity material is placed at the locations where reflex reflectors are required by Table 1; and (ii) The conspicuity material when installed on the...

  13. 49 CFR 230.56 - Water glass lamps.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Water glass lamps. 230.56 Section 230.56..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Water Glasses and Gauge Cocks § 230.56 Water glass lamps. All water glasses must be supplied with...

  14. 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.

  15. 21 CFR 878.4635 - Ultraviolet lamp for tanning.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultraviolet lamp for tanning. 878.4635 Section 878.4635 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4635 Ultraviolet lamp...

  16. 21 CFR 878.4635 - Ultraviolet lamp for tanning.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ultraviolet lamp for tanning. 878.4635 Section 878.4635 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4635 Ultraviolet lamp...

  17. 21 CFR 878.4635 - Ultraviolet lamp for tanning.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ultraviolet lamp for tanning. 878.4635 Section 878.4635 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4635 Ultraviolet lamp...

  18. 21 CFR 878.4635 - Ultraviolet lamp for tanning.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ultraviolet lamp for tanning. 878.4635 Section 878.4635 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4635 Ultraviolet lamp...

  19. 21 CFR 878.4635 - Ultraviolet lamp for tanning.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ultraviolet lamp for tanning. 878.4635 Section 878.4635 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4635 Ultraviolet lamp...

  20. 30 CFR 20.9 - Class 2 lamps.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... prevent unauthorized and unsafe opening of the compartments in a mine. (c) Locks or seals (battery). The battery shall be enclosed in a locked or sealed container that will prevent exposure of live terminals. (d) Temperature of lamp. The temperature of the lamp under conditions of use shall not be such that a person...

  1. Direct current ballast circuit for metal halide lamp

    NASA Technical Reports Server (NTRS)

    Lutus, P. (Inventor)

    1981-01-01

    A direct current ballast circuit for a two electrode metal halide lamp is described. Said direct current ballast circuit includes a low voltage DC input and a high frequency power amplifier and power transformer for developing a high voltage output. The output voltage is rectified by diodes and filtered by inductor and capacitor to provide a regulated DC output through commutating diodes to one terminal of the lamp at the output terminal. A feedback path from the output of the filter capacitor through the bias resistor to power the high frequency circuit which includes the power amplifier and the power transformer for sustaining circuit operations during low voltage transients on the input DC supply is described. A current sensor connected to the output of the lamp through terminal for stabilizing lamp current following breakdown of the lamp is described.

  2. Mobilizing slit lamp to the field: A new affordable solution.

    PubMed

    Farooqui, Javed Hussain; Jorgenson, Richard; Gomaa, Ahmed

    2015-11-01

    We are describing a simple and affordable design to pack and carry the slit lamp to the field. Orbis staff working on the Flying Eye Hospital (FEH) developed this design to facilitate mobilization of the slit lamp to the field during various FEH programs. The solution involves using a big toolbox, a central plywood apparatus, and foam. These supplies were cut to measure and used to support the slit lamp after being fitted snuggly in the box. This design allows easy and safe mobilization of the slit lamp to remote places. It was developed with the efficient use of space in mind and it can be easily reproduced in developing countries using same or similar supplies. Mobilizing slit lamp will be of great help for staff and institutes doing regular outreach clinical work.

  3. A comparative study of corneal incisions induced by diamond and steel knives and two ultraviolet radiations from an excimer laser.

    PubMed Central

    Marshall, J; Trokel, S; Rothery, S; Krueger, R R

    1986-01-01

    This paper reviews the potential role of excimer lasers in corneal surgery. The morphology of incisions induced by two wavelengths of excimer laser radiation, 193 nm and 248 nm, are compared with the morphology of incisions produced by diamond and steel knives. Analysis suggests that ablation induced by excimer laser results from highly localised photochemical reactions and that 193 nm is the optimal wavelength for surgery. The only significant complication of laser surgery is loss of endothelial cells when incisions are within 40 micron of Descemet's membrane. Images PMID:3013283

  4. Formation of short high-power laser radiation pulses in excimer mediums

    NASA Astrophysics Data System (ADS)

    Losev, V. F., Sr.; Ivanov, N. G.; Panchenko, Yu. N.

    2007-06-01

    Presently an excimer mediums continue are examined as one of variants for formation of powerful and over powerful pulses of laser radiation with duration from units of nanosecond up to tens femtosecond. The researches on such powerful installations as "NIKE" (USA) and << SUPER ASHURA >>, Japan) proceed in this direction. The main advantage of excimer mediums is the opportunity to work in a frequency mode, absence of restriction on the size of active area, high uniformity of a gas working medium, high efficiency (up to 10 %) and wide spectral range of laser radiation (KrF, XeCl ~ 2nm, XeF (C-A), Xe IICl ~ 50-100 nanometers). Research in area of high quality laser beams formation in excimer mediums and its amplification in high power amplifiers are carried out the long time in Institute of High Current Electronics SB RAS, Tomsk, Russia. The wide aperture XeCl laser system of MELS-4k is used for these investigations. Last time we take part in program on development of high power excimer laser system with a petawatt level of power. This system supposes the formation and amplification high quality laser beams with different pulse duration from units of nanosecond up to tens femtosecond. We research the possibility of laser beams formation in excimer mediums with ps-ns pulse duration having the low noise and divergence near to diffraction limit. In other hand, we are developing the wide aperture XeF(C-A) amplifier with optical pump on base electron accelerator. According to our estimations of the XeF(C-A) amplifier based on the converter of e-beam energy to the Xe II* fluorescence at 172 nm will allow to obtain up to 100 TW peak power in a 30 fs pulse.

  5. Excimer laser debulking for percutaneous coronary intervention in left main coronary artery disease.

    PubMed

    Topaz, On; Polkampally, Pritam R; Mohanty, Pramod K; Rizk, Maged; Bangs, Julie; Bernardo, Nelson L

    2009-11-01

    Excimer laser has been successfully applied to complex atherosclerotic plaques in acute coronary syndromes; however, its role in debulking in left main coronary artery disease has not been fully explored. Details of a series of 20 patients who underwent excimer laser revascularization of a spectrum of left main coronary artery lesions are presented. Twenty symptomatic patients who received excimer laser debulking were examined for procedural outcome and follow up results. The left main coronary artery was characterized as protected, semi-protected, poorly protected, or unprotected, depending on the presence or absence of patent bypass grafts to the left anterior descending (LAD) and circumflex (CX) arteries. A fully protected left main coronary artery (LMCA) was present in only 20% of the patients. The target lesions included 11(55%) distal LMCA stenoses, six (30%) ostial stenoses, and one (5%) mid-portion lesions. Two (10%) patients had in-stent re-stenosis of the entire length of the LMCA. Small (0.7 mm-1.4 mm) excimer laser catheters were mostly used. A relatively high number of laser energy pulses (1,334 +/- 643) were required to achieve adequate debulking. Successful LMCA intervention was performed in 19 (95%) patients, while in-hospital complications occurred in only one (5%) patient. Subacute/late stent thrombosis developed 3 months after the procedure in one patient, and two patients died from non-cardiac causes during follow-up. Lesions in LMCAs can be revascularized in selected patients by laser debulking and adjunct stenting. Inadequate protection by bypass grafts and decreased left ventricular function do not contradict utilization of excimer laser. Small laser catheters and high energy levels are required during laser debulking of stenoses of left main coronary arteries.

  6. Coatings for Energy Efficient Lamps with Cylindrical Geometry

    NASA Astrophysics Data System (ADS)

    Rancourt, James; Martin, Robert

    1986-09-01

    During the past several years, a high level of activity has been directed toward developing more efficient lighting products to meet consumer demand in the face of energy scarcity and its high cost. Without major redesign of lamps, manufacturers have been able to achieve modest gains of 5 to 10 percent in incandescent lamp efficacy by optimizing standard features such as filament design, gas fill, etc. What was desired for incandescent lamps was a major jump in efficacy of 30% or more. Much encouraging work, notably by Philips in the Netherlands, has already been accomplished in the laboratory using thin film reflectors to recycle the wasted infrared radiation from incandescent lamps. Indium tin oxide (ITO) films, which are transparent in the visible and reflect well at wavelengths greater than 2 micrometers, is a most attractive material for its simplicity and apparent high performance. It °has a serious drawback, however, in its inability to reflect adequately when its temperature exceeds 800 C. A separate outer jacket surrounding the lamp itself is required in order to keep the ITO coating cool and thereby take advantage of its properties. The use of this extra component makes this solution to the energy problem more expensive and complex. In the United States, the Duratest Corporation has developed a sophisticated silver coating which is deposited inside domestic type A-line lamps. About six years ago, the General Electric Co., a major U.S. lamp manufacturer, approached 0.C.L.I. and requested assistance in improving the quartz-halogen lamp. The G.E.-0.C.L.I. method that was developed for improving the efficacy of an incandescent lamp product consists of coating quartz-halogen lamps with infrared reflectors. These reflectors are interference reflector stacks made of refractory metal oxides using conventional thermal evaporation technology. These products have been available commercially for about three years.

  7. Danon disease: a phenotypic expression of LAMP-2 deficiency.

    PubMed

    Endo, Yukari; Furuta, Akiko; Nishino, Ichizo

    2015-03-01

    Danon disease is an X-linked disorder clinically characterized by the triad of hypertrophic cardiomyopathy, myopathy, and intellectual disability. Cardiomyopathy is a severe and life-threatening problem, for which cardiac transplantation is the only therapeutic option. The most striking finding in muscle biopsy samples is small basophilic granules scattered in myofibers, which are in fact small autophagic vacuoles surrounded by membranes with sarcolemmal features characterized by the recruitment of sarcolemmal proteins and acetylcholine esterase and by the presence of basal lamina on its luminal side. The mechanism underlying the formation of these autophagic vacuoles with unique sarcolemmal features (AVSF) still remains a mystery and its origin is unknown. In heart, cardiomyocytes show dramatically increased vacuolation and degenerative features, including myofibrillar disruption and lipofuscin accumulation. In brain, pale granular neurons and neurons with lipofuscin-like granules may be seen. Danon disease is caused by loss-of-function mutations in the LAMP2 gene, which encodes lysosome-associated membrane protein 2 (LAMP-2), a single-spanned transmembrane protein localized in the limiting membranes of lysosomes and late endosomes. Most mutations lead to splicing defects or protein truncation, resulting in a loss of transmembrane and/or cytoplasmic domains, leading to LAMP-2 protein deficiency. LAMP-2 is required for the maturation of autophagosomes by fusion with lysosomes; therefore, LAMP-2 deficiency leads to a failure in macroautophagy. There are three LAMP-2 isoforms, LAMP-2A, -2B, and -2C. Clinical features of Danon disease are thought to be mediated by loss of the LAMP-2B isoform which is the major isoform expressed in muscle. It is also known that LAMP-2 plays a role in chaperone-mediated autophagy and RNA- and DNA-targeting autophagy. However, the precise pathophysiological mechanism through which LAMP-2 deficiency causes Danon disease is still not fully

  8. CALiPER Benchmark Report: Performance of Incandescent A Type and Decorative Lamps and LED Replacements

    SciTech Connect

    Lingard, R. D.; Myer, M. A.; Paget, M. L.

    2008-11-01

    This benchmark report addresses common omnidirectional incandescent lamps - A-type and small decorative, candelabra-type lamps - and their commercially available light-emitting diode (LED) replacements.

  9. Automatic multidiagnosis system for slit lamp

    NASA Astrophysics Data System (ADS)

    Ventura, Liliane; Chiaradia, Caio; Vieira Messias, Andre M.; Faria de Sousa, Sidney J.; Isaac, Flavio; Caetano, Cesar A. C.; Rosa Filho, Andre B.

    2001-06-01

    We have developed a system for several automatic diagnose in Slit Lamp in order to provide 04 additional measurements to the biomicroscope: (1) counting of the endothelial cells of donated corneas; (2) automatic keratometry; (3) corneal ulcer evaluation; (4) measurement of linear distances and areas of the ocular image. The system consists in a Slit Lamp, a beam-splitter, some optical components, a CCD detector, a frame grabber and a PC. The optical components attached to the beam-splitter are the same for all the functions, except for 1. For function 1, we have developed an optical system that magnifies the image 290X and a software that counts the cells interactively and automatically. Results are in good agreement with commercial specular microscopes (correlation coefficient is 0,98081). The automatic keratometry function is able to measure cylinders over 30 di and also irregular astigmatisms. The system consists of projecting a light ring at the patient's cornea and the further analysis of the deformation of the ring provides the radius of curvature as well as the axis of the astigmatism. The nominal precision is 0,005 mm for the curvature radius and 2 degree(s) for the axis component. The results are in good agreement with commercial systems (correlation coefficient of 0,99347). For function 3, the ulcer is isolated by the usual clinical ways and the image of the green area is automatically detected by the developed software in order to evaluate the evolution of the disease. Function 4 simply allows the clinician do any linear or area measurement of the ocular image. The system is a low cost multi evaluation equipment and it is being used in a public hospital in Brazil.

  10. Application Summary Report 22: LED MR16 Lamps

    SciTech Connect

    Royer, Michael P.

    2014-07-23

    This report analyzes the independently tested photometric performance of 27 LED MR16 lamps. It describes initial performance based on light output, efficacy, distribution, color quality, electrical characteristics, and form factor, with comparisons to a selection of benchmark halogen MR16s and ENERGY STAR qualification thresholds. Three types of products were targeted. First, CALiPER sought 3000 K lamps with the highest rated lumen output (i.e., at least 500 lm) or a claim of equivalency to a 50 W halogen MR16 or higher. The test results indicate that while the initial performance of LED MR16s has improved across the board, market-available products still do not produce the lumen output and center beam intensity of typical 50 W halogen MR16 lamps. In fact, most of the 18 lamps in this category had lower lumen output and center beam intensity than a typical 35 W halogen MR16 lamp. Second, CALiPER sought lamps with a CRI of 90 or greater. Only four manufacturers were identified with a product in this category. CALiPER testing confirmed the performance of these lamps, which are a good option for applications where high color fidelity is needed. A vast majority of the LED MR16 lamps have a CRI in the low 80s; this is generally acceptable for ambient lighting, but may not always be acceptable for focal lighting. For typical LED packages, there is a fundamental tradeoff between CRI and efficacy, but the lamps in the high-CRI group in this report still offer comparable performance to the rest of the Series 22 products in other performance areas. Finally, CALiPER sought lamps with a narrow distribution, denoted as a beam angle less than 15°. Five such lamps were purchased. Notably, no lamp was identified as having high lumen output (500 lumens or greater), high CRI (90 or greater), a narrow distribution (15° or less), and an efficacy greater than 60 lm/W. This would be an important achievement for LED MR16s especially if output could reach approximately 700 800 lumens

  11. Highly Efficient Small Form Factor LED Retrofit Lamp

    SciTech Connect

    Steven Allen; Fred Palmer; Ming Li

    2011-09-11

    This report summarizes work to develop a high efficiency LED-based MR16 lamp downlight at OSRAM SYLVANIA under US Department of Energy contract DE-EE0000611. A new multichip LED package, electronic driver, and reflector optic were developed for these lamps. At steady-state, the lamp luminous flux was 409 lumens (lm), luminous efficacy of 87 lumens per watt (LPW), CRI (Ra) of 87, and R9 of 85 at a correlated color temperature (CCT) of 3285K. The LED alone achieved 120 lumens per watt efficacy and 600 lumen flux output at 25 C. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.90 at a power of only 5 watts. Compared to similar existing MR16 lamps using LED sources, these lamps had much higher efficacy and color quality. The objective of this work was to demonstrate a LED-based MR16 retrofit lamp for replacement of 35W halogen MR16 lamps having (1) luminous flux of 500 lumens, (2) luminous efficacy of 100 lumens per watt, (3) beam angle less than 40{sup o} and center beam candlepower of at least 1000 candelas, and (4) excellent color quality.

  12. REVIEW ARTICLE: UHP lamp systems for projection applications

    NASA Astrophysics Data System (ADS)

    Derra, Guenther; Moench, Holger; Fischer, Ernst; Giese, Hermann; Hechtfischer, Ulrich; Heusler, Gero; Koerber, Achim; Niemann, Ulrich; Noertemann, Folke-Charlotte; Pekarski, Pavel; Pollmann-Retsch, Jens; Ritz, Arnd; Weichmann, Ulrich

    2005-09-01

    Projection systems have found widespread use in conference rooms and other professional applications during the last decade and are now entering the home TV market at a considerable pace. Projectors as small as about one litre are able to deliver several thousand screen lumens and are, with a system efficacy of over 10 lm W-1, the most efficient display systems realized today. Short arc lamps are a key component for projection systems of the highest efficiency for small-size projection displays. The introduction of the ultra high performance (UHP) lamp system by Philips in 1995 can be identified as one of the key enablers of the commercial success of projection systems. The UHP lamp concept features outstanding arc luminance, a well suited spectrum, long life and excellent lumen maintenance. For the first time it combines a very high pressure mercury discharge lamp with extremely short and stable arc gap with a regenerative chemical cycle keeping the discharge walls free from blackening, leading to lifetimes of over 10 000 h. Since the introduction of the UHP lamp system, many important new technology improvements have been realized: burner designs for higher lamp power, advanced ignition systems, miniaturized electronic drivers and innovative reflector concepts. These achievements enabled the impressive increase of projector light output, a remarkable reduction in projector size and even higher optical efficiency in projection systems during the last years. In this paper the concept of the UHP lamp system is described, followed by a discussion of the technological evolution the UHP lamp has undergone so far. Last, but not least, the important improvements of the UHP lamp system including the electronic driver and the reflector are discussed.

  13. Impact of Xe partial pressure on the production of excimer vacuum ultraviolet emission for plasma display panels

    SciTech Connect

    Zhu Di; Zhang Xiong; Kajiyama, Hiroshi

    2012-08-01

    In this work, the effect of the Xe partial pressure on the excimer vacuum ultraviolet (VUV) emission intensity of the plasma display panels is investigated, both by measuring the spectral emission directly and by two-dimensional simulations. Experimentally, we find that at the high Xe partial pressure levels, there is an supra-linear increase of excimer VUV radiation and that determines the strong increase of luminance at the high pressures and high voltage. Due to the increase of the luminance and the almost unchanged discharge current, the luminous efficacy strongly increases with the Xe partial pressure. In addition, we also investigated the dynamics of the VUV generation, by measuring the decay time of the excimer VUV light as a function of the gas pressure. It is found that the decay time decreases with the increase of gas pressure. The spatial characteristics of the excimer VUV emission are also discussed. Different from the Ne and near-infrared emission, the excimer VUV emission is generated near the surface of the electrodes and increases uniformly on both sides of the anode and cathode (i.e., the bulk plasma region). Most importantly, it is found that the VUV production occurs during the afterglow period, while it is almost zero at the moment of the discharge itself. From the simulations, it can be seen that the Xe{sub 2}*({sup 3}{Sigma}{sub u}{sup +}) excimer species, which are generated from Xe*(1s{sub 5}), play a dominant role in the excimer VUV emission output at the high Xe partial pressure. The two-dimensional simulations also show that the strong increase of Xe excimer excitation states in the case of high pressure is mainly the result of the high conversion efficiency of the Xe excimer states, especially in the afterglow period. Due to the high conversion efficiency of Xe excitation species to Xe excimer species by the high collision rate in the case of high pressure, there is a strong increase of excimer VUV production, especially from the cathode.

  14. A Medical Excimer Laser System For Corneal Surgery And Laser Angioplasty

    NASA Astrophysics Data System (ADS)

    Caro, R. G.; Muller, D. F.

    1987-03-01

    The authors report the design criteria and performance of the ExciMeda UV200 medical excimer laser system. A beam delivery system for controlled photoablative machining of variable power optical lenses in organic material is described. Some of the potential applications of this delivery system in corneal surgery are presented. The uses of the UV200 laser system in other areas of medical research are discussed and, in particular, its application i the field of laser angioplasty is outlined. There has been considerable interest recently in the use of excimer lasers in a variety of fields in medicine. The ultraviolet, high peak power beam emitted by an excimer laser has been shown to be capable of producing very clean and precise cuts in organic material. In particular, cuts can be made in biological material with minimal disturbance of the material adjacent to the cut. For example, tissue can be cut in such a way as to produce negligible charring or vacuolization in adjacent areas of the tissue. This is in marked contrast to the results when organic material is cut by a continuous wave laser such as an Argon ion laser, or c.w. CO2 laser. The potential applications in clinical settings which are suggested by this feature of the interaction of tissue with excimer laser radiation have been largely unrealized outside the laboratory as yet. A primary reason for this is that, until recently, excimer lasers have been available only in a form that was suitable for the scientific laboratory. These lasers required large amounts of space, were not mobile once installed, and required con nection to external sources of water cooling, vacuum exhaust, a high current electrical supply, and a variety of gas bottles including the gases F2 and C12. These systems were not designed with clinical applications in mind, and thus provided unnecessary performance features at the cost of added complexity. They also posed potential electrical and gaseous safety hazards not suitable for a

  15. 46 CFR 32.85-1 - Fireproofing of lamp, oil and paint rooms-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Fireproofing of lamp, oil and paint rooms-T/ALL. 32.85-1..., MACHINERY, AND HULL REQUIREMENTS Lamp and Paint Rooms and Similar Compartments on Tankships § 32.85-1 Fireproofing of lamp, oil and paint rooms—T/ALL. Lamp, oil and paint rooms shall be wholly and tightly...

  16. 46 CFR 32.85-1 - Fireproofing of lamp, oil and paint rooms-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Fireproofing of lamp, oil and paint rooms-T/ALL. 32.85-1..., MACHINERY, AND HULL REQUIREMENTS Lamp and Paint Rooms and Similar Compartments on Tankships § 32.85-1 Fireproofing of lamp, oil and paint rooms—T/ALL. Lamp, oil and paint rooms shall be wholly and tightly...

  17. 46 CFR 32.85-1 - Fireproofing of lamp, oil and paint rooms-T/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Fireproofing of lamp, oil and paint rooms-T/ALL. 32.85-1..., MACHINERY, AND HULL REQUIREMENTS Lamp and Paint Rooms and Similar Compartments on Tankships § 32.85-1 Fireproofing of lamp, oil and paint rooms—T/ALL. Lamp, oil and paint rooms shall be wholly and tightly...

  18. 46 CFR 32.85-1 - Fireproofing of lamp, oil and paint rooms-T/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Fireproofing of lamp, oil and paint rooms-T/ALL. 32.85-1..., MACHINERY, AND HULL REQUIREMENTS Lamp and Paint Rooms and Similar Compartments on Tankships § 32.85-1 Fireproofing of lamp, oil and paint rooms—T/ALL. Lamp, oil and paint rooms shall be wholly and tightly...

  19. 46 CFR 32.85-1 - Fireproofing of lamp, oil and paint rooms-T/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Fireproofing of lamp, oil and paint rooms-T/ALL. 32.85-1..., MACHINERY, AND HULL REQUIREMENTS Lamp and Paint Rooms and Similar Compartments on Tankships § 32.85-1 Fireproofing of lamp, oil and paint rooms—T/ALL. Lamp, oil and paint rooms shall be wholly and tightly...

  20. Compact fluorescent lamp using horizontal and vertical insulating septums and convective venting geometry

    DOEpatents

    Siminovitch, M.

    1998-02-10

    A novel design is described for a compact fluorescent lamp, including a lamp geometry which will increase light output and efficacy of the lamp in a base down operating position by providing horizontal and vertical insulating septums positioned in the ballast compartment of the lamp to provide a cooler coldspot. Selective convective venting provides additional cooling of the ballast compartment. 9 figs.

  1. Compact fluorescent lamp using horizontal and vertical insulating septums and convective venting geometry

    DOEpatents

    Siminovitch, Michael

    1998-01-01

    A novel design for a compact fluorescent lamp, including a lamp geometry which will increase light output and efficacy of the lamp in a base down operating position by providing horizontal and vertical insulating septums positioned in the ballast compartment of the lamp to provide a cooler coldspot. Selective convective venting provides additional cooling of the ballast compartment.

  2. Structure-process-property relations in excimer laser surface processed Ti-6Al-4V alloy

    SciTech Connect

    Jervis, T.R.; Zocco, T.G.; Steele, J.H. Jr.

    1990-01-01

    Excimer laser processing results in very rapid solidification of metal surfaces. In addition to mixing or segregation processes, rapid heat treatment can result in phase transformations which yield beneficial surface properties. We have investigated the effect of pulsed excimer laser radiation on the microstructure and surface hardness of Ti-6Al-4V alloy. This material undergoes a well defined martensite transformation during rapid quenching from temperatures in the {beta} phase field. The depth of the transformed layer is thus a marker for the temperature profile during processing. We find that the depth of the transformed layer agrees well with a simple 1-D calculation of heat flow following the laser pulse. As measured by the nanoindenter, we find that the surface martensite is softer than the as-rolled alloy. Multiple pulse processing at high fluences results in an increase in surface hardness, but at a depth much less than that of the martensite, suggesting an independent mechanism. 10 refs., 4 figs.

  3. Excimer laser treatment of corneal surface pathology: a laboratory and clinical study.

    PubMed Central

    Gartry, D.; Kerr Muir, M.; Marshall, J.

    1991-01-01

    The argon fluoride excimer laser emits radiation in the far ultraviolet part of the electromagnetic spectrum (193 nm). Each photon has high individual energy. Exposure of materials or tissues with peak absorption around 193 nm results in removal of surface layers (photoablation) with extremely high precision and minimal damage to non-irradiated areas. This precision is confirmed in a series of experiments on cadaver eyes and the treatment of 25 eyes with anterior corneal disease (follow-up 6 to 30 months). Multiple zone excimer laser superficial keratectomy is considered the treatment of choice for rough, painful corneal surfaces. All patients in this group were pain-free postoperatively. Where good visual potential exists, ablation of a single axial zone is recommended and results in improved visual acuity and reduction of glare. A hyperopic shift was noted in this group. Images PMID:1817467

  4. X-ray photoelectron spectroscopy study of excimer laser treated alumina films

    NASA Astrophysics Data System (ADS)

    Georgiev, D. G.; Kolev, K.; Laude, L. D.; Mednikarov, B.; Starbov, N.

    1998-01-01

    Amorphous alumina layers are deposited on a single crystal Si substrate by a e-gun evaporation technique. These films are then thermally annealed in oxygen to be crystallized and, further, irradiated with an excimer laser beam. At each stage of the film preparation, an x-ray photoelectron spectroscopy analysis is performed at the film surface and in depth, upon ion beam grinding. Results give evidence for the formation of an aluminosilicate upon thermal annealing of the film in oxygen. At the surface itself, this compound is observed to decompose upon excimer laser irradiation at energy densities exceeding 1.75 J/cm2, giving rise to free Si atoms and SiO2, however with complete disappearance of Al atoms. Model photochemical reactions are proposed to explain such transformations.

  5. Ocular drug permeation following experimental excimer laser treatment on the isolated pig eye.

    PubMed

    Scholz, Martina; Schründer, Stephan; Gärtner, Sven; Keipert, Sigrid; Hartmann, Christian; Pleyer, Uwe

    2002-04-01

    Excimer laser photorefractive keratectomy (PRK) is a well-established procedure which is frequently applied to correct myopia. Since structural alterations of the corneal epithelium occur after the treatment, a different drug permeation can be assumed. To investigate the effects of PRK on drug permeation, excimer laser ablations with varying depths were performed on isolated pig eyes. The permeation of lipophilic (diclofenac-sodium; D-Na) and hydrophilic (pilocarpine-hydrochloride; P-HCl model drugs were studied in vitro. Under these experimental conditions, P-HCl demonstrated a significant (p < 0.05) enhancement of permeation in relation to the ablation depth. In contrast, corneal epithelial thickness scarcely influenced the permeation rate of D-Na. Not until removing the entire epithelium did a significantly increased permeability occur, when compared to untreated cornea. These results suggest that PRK may significantly reduce the corneal barrier function and alter pharmacokinetics of topical medication.

  6. Detection of lead in soil with excimer laser fragmentation fluorescence spectroscopy (ELFFS)

    SciTech Connect

    Choi, J.H.; Damm, C.J.; O'Donovan, N.J.; Sawyer, R.F.; Koshland, C.P.; Lucas, D.

    2004-03-01

    Excimer laser fragmentation fluorescence spectroscopy (ELFFS) is used to monitor lead in soil sample and investigate laser-solid interactions. Pure lead nitrate salt and soil doped with lead nitrate are photolyzed with 193 nm light from an ArF excimer at fluences from 0.4 to 4 J/cm{sup 2}. Lead emission is observed at 357.2, 364.0, 368.3, 373.9 and 405.8 nm. Time-resolved data show the decay time of the lead emission at 405.8 nm grows with increasing fluence, and a plasma is formed above fluences of 2 J/cm{sup 2}, where a strong continuum emission interferes with the analyte signal. Fluences below this threshold allow us to achieve a detection limit of approximately 200 ppm in soil.

  7. Bound-bound transitions in the emission spectra of Ba+-He excimer

    NASA Astrophysics Data System (ADS)

    Moroshkin, P.; Kono, K.

    2016-05-01

    We present an experimental and theoretical study of the emission and absorption spectra of the Ba+ ions and Ba+*He excimer quasimolecules in the cryogenic Ba-He plasma. We observe several spectral features in the emission spectrum, which we assign to the electronic transitions between bound states of the excimer correlating to the 6 2P3 /2 and 5 2D3 /2 ,5 /2 states of Ba+. The resulting Ba+(5 2DJ) He is a metastable electronically excited complex with orbital angular momentum L =2 , thus expanding the family of known metal-helium quasimolecules. It might be suitable for high-resolution spectroscopic studies and for the search for new polyatomic exciplex structures.

  8. High power repetitive excimer lasers pumped by an all solid state magnetic exciter

    NASA Astrophysics Data System (ADS)

    Kobayashi, Osamu; Noda, Koji; Shimada, Tsutomu; Obara, Minoru

    1986-01-01

    In a high repetition rate excimer laser operation, the lifetime of the exciter is one of the most important problems. To attain a nearly endless lifetime of the excimer laser exciter, an all-solid-state exciter has been developed which consists of a high-voltage transformer switched by a silicon-controlled rectifier, producing a pulse whose energy and duration are 11.2 J and 8 microns, respectively, and a three-stage magnetic compressor. With a 1.4-ohm dummy load, output peak power, energy/pulse, and pulse duration were 100 MW, 5.2 J, and 100 ns, respectively. The electrical efficiency of the exciter was 47 percent. The energy loss of 6 J in the exciter was due both to the core loss and the transfer loss. It should be noted that the time jitter between the SCR gate input pulse and the output voltage pulse was less than 12 ns.

  9. Light shield and cooling apparatus. [high intensity ultraviolet lamp

    NASA Technical Reports Server (NTRS)

    Meador, T. G., Jr. (Inventor)

    1974-01-01

    A light shield and cooling apparatus was developed for a high intensity ultraviolet lamp including water and high pressure air for cooling and additional apparatus for shielding the light and suppressing the high pressure air noise.

  10. Purging means and method for Xenon arc lamps

    NASA Technical Reports Server (NTRS)

    Miller, C. G. (Inventor)

    1973-01-01

    High pressure Xenon short-arc lamp with two reservoirs which are selectively connectable to the lamp's envelope is described. One reservoir contains an absorbent which will absorb both Xenon and contaminant gases such as CO2 and O2. The absorbent temperature is controlled to evacuate the envelope of both the Xenon and the contaminant gases. The temperature of the absorbent is then raised to desorb only clean Xenon while retaining the contaminant gases, thereby clearing the envelope of the contaminant gases. The second reservoir contains a gas whose specific purpose is, to remove the objectional metal film which deposits gradually on the interior surface of the lamp envelope during normal arc operation. The origin of the film is metal transferred from the cathode of the arc lamp by sputtering or other gas transfer processes.

  11. 13. View of Picking Shakers, Steam Picking Shaker (right), Lamp ...

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

    13. View of Picking Shakers, Steam Picking Shaker (right), Lamp Picking Shaker (right) Photograph taken by Joseph E.B. Elliot - Huber Coal Breaker, Breaker, 101 South Main Street, Ashley, Luzerne County, PA

  12. 34. VIEW TO EAST; DETAIL OF LAMP ON VEHICULAR RAMP ...

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

    34. VIEW TO EAST; DETAIL OF LAMP ON VEHICULAR RAMP LIGHTING PYLON (Dobson) - Los Angeles Union Passenger Terminal, Mail, Baggage, & Express Building, 800 North Alameda Street, Los Angeles, Los Angeles County, CA

  13. One piece microwave container screens for electrodeless lamps

    DOEpatents

    Turner, Brian; Ury, Michael

    1998-01-01

    A microwave powered electrodeless lamp includes an improved screen unit having mesh and solid sections with an internal reflector to reflect light into a light-transmitting chamber defined in the lamp microwave cavity by the reflector and the mesh section. A discharge envelope of a bulb is disposed in the light-transmitting chamber. Light emitted from the envelope is prevented by the reflector from entering the cavity portion bounded by the solid section of the screen. Replacing mesh material by solid metal material as part of the screen unit significantly reduces leakage of microwave energy from the lamp. The solid section has multiple compliant fingers defined therein for engaging the periphery of a flange on the waveguide unit so that a hose clamp can easily secure the screen to the assembly. Screen units of this type having different mesh section configurations can be interchanged in the lamp assembly to produce different respective illumination patterns.

  14. 214. RUSTIC BUS SHELTER, GUARDRAILS AND LAMP POST BELLE HAVEN ...

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

    214. RUSTIC BUS SHELTER, GUARDRAILS AND LAMP POST BELLE HAVEN BUS STOP WIDENING, 1932. - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

  15. Interior view, law library (note one of aluminum lamps designed ...

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

    Interior view, law library (note one of aluminum lamps designed by Jennwein is in the foreground; the murals were painted by Maurice Sterne) - United States Department of Justice, Constitution Avenue between Ninth & Tenth Streets, Northwest, Washington, District of Columbia, DC

  16. Sensitivity of an illumination system to lamp flicker

    NASA Astrophysics Data System (ADS)

    Rehn, H.

    2008-09-01

    Discharge lamps serve a wide variety of applications and outperform novel light sources such as LEDs in terms of luminous flux and luminance. Unfortunately, such lamps occasionally show arc movements (flicker) which change the amount of light that is coupled into an optical system. A variety of measures in lamp design can suppress flicker tendencies of a lamp but arc movement cannot be totally avoided. In our contribution, we show that the way how the light is collected considerably influences the impact of flicker on the collected luminous flux. We investigate light collection sensitivity of an illumination system as a function of the etendue and of the particular realization of the illumination system. As a result, flicker sensitivity can be substantially reduced at the expense of collection efficiency.

  17. VIEW OF LAMP FIXTURE (EXTERIOR) ADJACENT TO ENTRANCE AT SOUTHWEST ...

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

    VIEW OF LAMP FIXTURE (EXTERIOR) ADJACENT TO ENTRANCE AT SOUTHWEST CORNER OF BUILDING 23, FACING NORTH - Roosevelt Base, Auditorium-Gymnasium, West Virginia Street between Richardson & Reeves Avenues, Long Beach, Los Angeles County, CA

  18. Closeup view of EPA Farm cattle shelter lamp, facing west ...

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

    Close-up view of EPA Farm cattle shelter lamp, facing west - Nevada Test Site, Environmental Protection Agency Farm, Shelter Unit Type, Area 15, Yucca Flat, 10-2 Road near Circle Road, Mercury, Nye County, NV

  19. Sculpture, detail view of cast iron lamps, with scale (note: ...

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

    Sculpture, detail view of cast iron lamps, with scale (note: "'J.L. Mott, Ironworks, NY" stamp on the base) - National Park Seminary, Bounded by Capitol Beltway (I-495), Linden Lane, Woodstove Avenue, & Smith Drive, Silver Spring, Montgomery County, MD

  20. Sculpture, cast iron lamps at northeast corner of Stephen Sitter ...

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

    Sculpture, cast iron lamps at northeast corner of Stephen Sitter Avenue and Forney road, with scale - National Park Seminary, Bounded by Capitol Beltway (I-495), Linden Lane, Woodstove Avenue, & Smith Drive, Silver Spring, Montgomery County, MD

  1. 25. Detail of cast iron lamp post base with fluted ...

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

    25. Detail of cast iron lamp post base with fluted wooded post at top, located at north end of bridge. VIEW NORTHEAST - Chelsea Street Bridge & Draw Tender's House, Spanning Chelsea River, Boston, Suffolk County, MA

  2. High-luminance LEDs replace incandescent lamps in new applications

    NASA Astrophysics Data System (ADS)

    Evans, David L.

    1997-04-01

    The advent of high luminance AlInGaP and InGaN LED technologies has prompted the use of LED devices in new applications formally illuminated by incandescent lamps. The luminous efficiencies of these new LED technologies equals or exceeds that attainable with incandescent sources, with reliability factors that far exceed those of incandescent sources. The need for a highly efficient, dependable, and cost effective replacement for incandescent lamps is being fulfilled with high luminance LED lamps. This paper briefly described some of the new applications incorporating high luminance LED lamps, traffic signals and roadway signs for traffic management, automotive exterior lighting, active matrix and full color displays for commercial advertising, and commercial aircraft panel lighting and military aircraft NVG compatible lighting.

  3. Studies on Temperature Dependence of Rubidium Lamp for Atomic Frequency Standard

    NASA Astrophysics Data System (ADS)

    Ghosal, Bikash; Banik, Alak; Vats, Vaibhav; Pal, Sukamal; Bahl, R. K.

    2011-10-01

    Rb lamp is a very critical component of the Rb atomic clock's Physics Package. The Rb lamp's performance is very sensitive to temperature and its stability. In this paper we discuss the behaviors of Rb Lamp with temperature. The Rb lamp exciter power and temperature of Rb bulb are very important parameters in controlling the performance of the Rb Lamp. It is observed that at temperatures beyond 110° C, the lamp mode changes from the ring to red mode resulting in abnormal broadening of emission lines and self reversal. The results of our studies on spectral analysis of Rb lamp under various operating conditions are reported in the paper.

  4. Studies on Temperature Dependence of Rubidium Lamp for Atomic Frequency Standard

    SciTech Connect

    Ghosal, Bikash; Banik, Alak; Vats, Vaibhav; Pal, Sukamal; Bahl, R. K

    2011-10-20

    Rb lamp is a very critical component of the Rb atomic clock's Physics Package. The Rb lamp's performance is very sensitive to temperature and its stability. In this paper we discuss the behaviors of Rb Lamp with temperature. The Rb lamp exciter power and temperature of Rb bulb are very important parameters in controlling the performance of the Rb Lamp. It is observed that at temperatures beyond 110 deg. C, the lamp mode changes from the ring to red mode resulting in abnormal broadening of emission lines and self reversal. The results of our studies on spectral analysis of Rb lamp under various operating conditions are reported in the paper.

  5. Life of fluorescent lamps operated at high frequencies with solid-state ballasts

    NASA Astrophysics Data System (ADS)

    Verderber, R. R.; Morse, O.; Rubinstein, F. M.

    1985-07-01

    Standard 40-watt, F-40, rapid-start, fluorescent lamps were operated with solid-state ballasts following the standard life-testing cycle of 3 hours on and 20 minutes off for more than 20,000 hours at high frequency. Lamp operating characteristics (starting voltage, filament voltage, arc current, and current-crest factor) were studied as factors affecting lamp life. Measurements show that fluorescent lamps can attain rated life at high frequency using solid-state ballasts. When lamps are operated in the dimmed mode, full filament power is required to sustain lamplife. The rate of lamp lumen depreciation is dependent on the lamp loading and not the operating frequency.

  6. Cancer morbidity in lamp manufacturing workers.

    PubMed

    Shannon, H S; Haines, T; Bernholz, C; Julian, J A; Verma, D K; Jamieson, E; Walsh, C

    1988-01-01

    A historical prospective study of cancer in lamp manufacturing workers in one plant was conducted. All men and women who worked for a total of at least 6 months and were employed at some time between 1960 and 1975 were included. Work histories were abstracted and subjects were divided according to whether they had worked in the coiling and wire drawing area (CWD). Cancer morbidity from 1964 to 1982 was ascertained via the provincial registry, and was compared with the site-specific incidence in Ontario, adjusting for age, sex and calendar period. Of particular interest were primary breast and gynecological cancers in women. The cancers of a priori concern were significantly increased in women in CWD, but not elsewhere in the plant. The excess was greatest in those with more than 5 yr exposure (in CWD) and more than 15 yr since first working in CWD, with eight cases of breast and gynecological cancers observed in this category compared with 2.67 expected. Only three cancers occurred in men in CWD. Environmental measurements had not been made in the past and little information was available on substances used in the 1940s and 1950s, the period when the women with the highest excess began employment. It is known that methylene chloride and trichlorethylene have been used, but not enough is known about the dates and patterns of use to draw any conclusions about their relationship with the increase in disease.

  7. Lamp method and apparatus using multiple reflections

    DOEpatents

    MacLennan, Donald A.; Turner, Brian P.

    2001-01-01

    An electrodeless microwave discharge lamp includes an envelope with a discharge forming fill disposed therein which emits light, the fill being capable of absorbing light at one wavelength and re-emitting the absorbed 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, a source of microwave energy coupled to the fill to excite the fill and cause the fill to emit light, and a reflector disposed within the microwave cavity and configured to reflect at least 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.

  8. Corneal astigmatism measuring module for slit lamps

    NASA Astrophysics Data System (ADS)

    Ventura, L.; Riul, C.; Sousa, S. J. F.; DeGroote, J. G. S.; Rosa Filho, A. B.; Oliveira, G. C. D.

    2006-06-01

    We have developed an automatic keratometer module for slit lamps that provides automatic measurements of the radii of the corneal curvature. The system projects 72 light spots displayed in a precise circle at the examined cornea. The displacement and deformation of the reflected image of these light spots are analysed providing the keratometry. Measurements in the range of 26.8-75 D can be obtained and a self-calibration system has been specially designed in order to keep the system calibrated. Infrared LEDs indicate automatically which eye is being examined. Volunteer patients (492) have been submitted to the system and the results show that our system has a high correlation factor with the commercially available manual keratometers and the keratometry measurements from a topographer. Our developed system is 95% in agreement with the corneal topographer (Humphrey—Atlas 995 CZM) and the manual keratometer (Topcon OM-4). The system's nominal precision is 0.05 mm for the radii of curvature and 1° for the associated axis. This research has been supported by Fundação de Apoio à Pesquisa do Estado de São Paulo (FAPESP).

  9. The LAMP instrument at the LCLS

    NASA Astrophysics Data System (ADS)

    Osipov, Timur; Castagna, Jean-Charles; Bostedt, Christoph; Xiong, Hui; Ferguson, Ken; Bucher, Maximilian; Berrah, Nora

    2015-05-01

    We have commissioned and used a new instrument at the Linac Coherent Light (LCLS) Source at SLAC National Laboratory called LAMP. It consists of several detectors housed in a double chambered vacuum system. One detection scheme offered relies on the use of a double velocity map imaging (VMI) spectrometer which enables research in the gas phase such as molecular dynamics experiments. The latter are monitored via the detection of electron and ionic fragments resulting from x-ray photo-absorption of x-ray photons. With this new tool, we can record the different fragmentation pathways by measuring multi-particles ion-ion coincidences/multi-particle correlations. We can also simultaneously image the electrons momenta to capture the most detailed x-ray induced reaction in molecules and nano-systems. The other detection scheme offered consists of two imaging detectors of the pnCCD type for diffraction experiments of clusters and bio-specimens. This instrument, available to any users, has the possibility to uncover new mechanisms in physics, chemistry and biology. This work is funded in part by the Department of Energy, Office of Science, Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences under a SISGR grant and funds from the LCLS, funded by DOE-BES.

  10. Excimer laser material processing: state-of-the-art and new approaches in microsystem technology

    NASA Astrophysics Data System (ADS)

    Pfleging, W.; Przybylski, M.; Brückner, H. J.

    2006-02-01

    In this paper the current state of the art and new trends in excimer laser processing of polymer materials are presented. Two processing regimes are of general interest: below and above the ablation threshold. The modification of polymer surface can be carried out by laser processing below ablation threshold. This is successfully demonstrated for the fabrication of optical singlemode waveguides in PMMA for the visible optical range and for 1550 nm. The obtained structures reveal absorption losses in the order of 1.4 dB/cm up to 5 dB/cm. Laser exposure using contact masks or direct scanning of planar structures are appropriate methods for the integration of optical waveguides in PMMA sensor devices (Y-branch). Above the ablation threshold excimer laser micromachining is a powerful tool for a rapid manufacturing of complex three-dimensional micro-structures in polymer surfaces with depths between 0.1 μm and 1000 μm and aspect ratios up to 10. Typical application fields are presented in micro-optics, micro-fluidics and rapid tooling. Micro-Laser-LIGA is established in order to fabricate nebulizer membranes, micro-fluidic devices and integrated single mode waveguides. Furthermore, the fabrication of 3d-shapes in metallic mold inserts is successfully demonstrated. Debris formation is completely suppressed. Polymer structuring with a low power short pulse excimer laser with high repetition rates up to 500 Hz is compared to the structuring with a "conventional" high power excimer laser with a repetition rate of about 10-100Hz as well as with a UV-Nd:YAG (1-2 kHz). These "high-repetition-rateexcimer lasers" with relatively small pulse energies but with much shorter laser pulse duration (< 6 ns) provide a significant improvement of pattern quality. Furthermore, the high repetition rate enables a fast material processing which is discussed in detail for several application fields.

  11. Phosphorus doping of 4H SiC by liquid immersion excimer laser irradiation

    SciTech Connect

    Ikeda, Akihiro; Nishi, Koji; Ikenoue, Hiroshi; Asano, Tanemasa

    2013-02-04

    Phosphorus doping of 4H SiC is performed by KrF excimer laser irradiation of 4H SiC immersed in phosphoric acid. Phosphorus is incorporated to a depth of a few tens of nanometers at a concentration of over 10{sup 20}/cm{sup 3} without generating significant crystal defects. Formation of a pn junction diode with an ideality factor of 1.06 is demonstrated.

  12. Remarks on the determination of the fraction of excimer sites in macromolecules

    NASA Astrophysics Data System (ADS)

    Sienicki, K.; Bojarski, C.

    1985-02-01

    A mathematical model taking into consideration excitation energy migration has been proposed in order to determine the fraction of excimer sites (FES) in synthetic macromolecules. Data for polystyrene and iso- and atactic poly(ar-methyl styrene0 of varying molecular mass have been taken from the work of Ishii, Handa and Matsunaga and re-worked in terms of the proposed model. The FES obtained are compared with those determined from other models.

  13. A comparison of the characteristics of excimer and femtosecond laser ablation of acrylonitrile butadiene styrene (ABS)

    NASA Astrophysics Data System (ADS)

    See, Tian Long; Liu, Zhu; Li, Lin; Zhong, Xiang Li

    2016-02-01

    This paper presents an investigation on the ablation characteristics of excimer laser (λ = 248 nm, τ = 15 ns) and femtosecond laser (λ = 800 nm, τ = 100 fs) on ABS polymer sheets. The laser-material interaction parameters (ablation threshold, optical penetration depth and incubation factor) and the changes in material chemical properties were evaluated and compared between the two lasers. The work shows that the ablation threshold and effective optical penetration depth values are dependent on the wavelength of laser beam (photon energy) and the pulse width. The ablation threshold value is lower for the excimer laser ablation of ABS (Fth = 0.087 J/cm2) than that for the femtosecond laser ablation of ABS (Fth = 1.576 J/cm2), demonstrating a more dominating role of laser wavelength than the pulse width in influencing the ablation threshold. The ablation depth versus the logarithmic scale of laser fluence shows two linear regions for the fs laser ablation, not previously known for polymers. The effective optical penetration depth value is lower for excimer laser ablation (α-1 = 223 nm) than that for femtosecond laser ablation (α-1 = 2917 nm). The ablation threshold decreases with increasing number of pulses (NOP) due to the chain scission process that shortens the polymeric chains, resulting in a weaker polymeric configuration and the dependency is governed by the incubation factor. Excimer laser treatment of ABS eliminates the Cdbnd C bond completely through the chain scission process whereas Cdbnd C bond is partially eliminated through the femtosecond laser treatment due to the difference in photon energy of the two laser beams. A reduction in the Cdbnd C bond through the chain scission process creates free radical carbons which then form crosslinks with each other or react with oxygen, nitrogen and water in air producing oxygen-rich (Csbnd O and Cdbnd O bond) and nitrogen-rich (Csbnd N) functional groups.

  14. High excimer-state emission of perylene bisimides and recognition of latent fingerprints.

    PubMed

    Wang, Ke-Rang; Yang, Zi-Bo; Li, Xiao-Liu

    2015-04-07

    High excimer-state emission in the H-type aggregate of a novel asymmetric perylene bisimide derivative, 6, with triethyleneglycol chains and lactose functionalization was achieved in water. Furthermore, its application for enhancing the visualization of transfer latent fingerprints from glass slides to the poly(vinylidene fluoride) (PVDF) membrane was explored, which showed clear images of the latent fingerprint in daylight and under 365 nm ultraviolet illumination.

  15. [Therapy of psoriasis with the Philips TL-01 ultraviolet lamp].

    PubMed

    Barth, J; Pinzer, B

    1990-01-01

    22 patients suffering from exanthematic psoriasis were irradiated with the UV-lamps UVS 65-2 (Narva, Brand-Erbisdorf) or TL-01 (Philips Company, Eindhoven, Niederlande) respectively. The latter one emits a narrow-band UV-spectrum at 311 nm which seems to be most suitable for the treatment of psoriasis. On our condition the clearing rate was higher and the cumulative irradiation dose was significantly lower with the TL-01 lamp.

  16. Magnetic fluorescent lamp having reduced ultraviolet self-absorption

    DOEpatents

    Berman, Samuel M.; Richardson, Robert W.

    1985-01-01

    The radiant emission of a mercury-argon discharge in a fluorescent lamp assembly (10) is enhanced by providing means (30) for establishing a magnetic field with lines of force along the path of electron flow through the bulb (12) 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.

  17. Study on the electromagnetic radiation characteristics of discharging excimer laser system

    NASA Astrophysics Data System (ADS)

    Zhao, Duliang; Liang, Xu; Fang, Xiaodong; Wang, Qingsheng

    2016-10-01

    Excimer laser in condition of high voltage, large current and fast discharge will produce strong electromagnetic pulse radiation and electromagnetic interference on the around electrical equipment. The research on characteristics and distribution of excimer laser electromagnetic radiation could provide important basis for electromagnetic shielding and suppressing electromagnetic interference, and further improving the electromagnetic compatibility of system. Firstly, electromagnetic radiation source is analyzed according to the working principle of excimer laser. The key test points of the electromagnetic radiation, hydrogen thyratron, main discharge circuit and laser outlet, are determined by the mechanical structure and the theory of electromagnetic radiation. Secondly, characteristics of electromagnetic field were tested using a near field probe on the key positions of the vertical direction at 20, 50, and 80 cm, respectively. The main radiation frequencies and the radiation field characteristics in the near field are obtained. The experimental results show that the main radiation frequencies distribute in 47, 65, and 130 MHz for electric field and the main radiation frequencies distribute in 34, 100, and 165 MHz for magnetic field. The intensity of electromagnetic field decreases rapidly with the increase of test distance. The higher the frequency increases, the faster the amplitude attenuate. Finally, several electromagnetic interference suppression measurement methods are proposed from the perspective of electromagnetic compatibility according to the test results.

  18. Expression of Epidermal c-Kit+ of Vitiligo Lesions Is Related to Responses to Excimer Laser

    PubMed Central

    Park, Oun Jae; Han, Ji Su; Lee, Sang Hyung; Park, Chan-Sik; Won, Chong Hyun; Lee, Mi Woo; Choi, Jee Ho

    2016-01-01

    Background The survival and growth of melanocytes are controlled by the binding of stem cell factor to its cell surface receptor c-kit+ (CD117). We have observed that c-kit+ melanocytes existed in some lesions of vitiligo, while Melan A+ cells were absent. Objective To verify possible relation between c-kit+ expression and treatment response in non-segmental vitiligo lesions Methods Skin biopsies were done from the center of the 47 lesions from the 47 patients with non-segmental vitiligo. Expression of c-kit+ and Melan A, and amounts of melanin in the epidermis were assessed in each lesion, and treatment responses to excimer laser were evaluated. Results Thirty-five of the 47 lesions (74.5%) had c-kit+ phenotypes. There was significant difference of c-kit staining value between good responders in 3 months of excimer laser treatment (average of 24 sessions) and the others. Conclusion c-Kit expression in vitiliginous epidermis may be related to better treatment responses to excimer laser. PMID:27489428

  19. Percutaneous excimer laser coronary angioplasty: development of technology and initial clinical results

    NASA Astrophysics Data System (ADS)

    Tcheng, James E.; Miller, James S.; Songer, Ronald W.; Golobic, Robert A.

    1992-08-01

    The development of laser systems suitable for vascular angioplasty is a multidisciplinary endeavor that includes development of the laser energy source, guidance modality, delivery catheter, and assessment of clinical applicability. In this paper we report on the design criteria of percutaneous coronary catheters and how these have guided development of the Spectranetics excimer laser angioplasty system. The Spectranetics CVX-300TM excimer laser angioplasty system was designed for safe application in the cardiac catheterization laboratory while maximizing system maintenance intervals. Recent improvements in catheter design and construction have been directed at optimizing target lesion acquisition and treatment. Lesion access and alignment have been facilitated through the use of optical fiber bundles with increased flexibility. Ablation efficiency has been improved by a combination of increased active fiber area and optimization of the radial location of the fiber array compared to the original devices. Engineered stiffness profiles have been improved and lubricous coatings incorporated to optimize force transmission and tactile feedback for the clinician. Initial clinical results appear favorable. In particular, excimer laser angioplasty appears to have an advantage in the treatment of complex coronary lesions such as diffuse coronary arterial disease, total occlusions, ostial stenoses, moderately calcified lesions, and vein graft disease. In these settings, improved procedural success rates and a lowered incidence of complications have been observed compared to conventional balloon PTCA angioplasty. Examples of complex coronary lesion cases as well as a summary of the data of the initial clinical results from the multicenter trial are also presented in this paper.

  20. On couplings and excimers: lessons from studies of singlet fission in covalently linked tetracene dimers.

    PubMed

    Feng, Xintian; Krylov, Anna I

    2016-03-21

    Electronic factors controlling singlet fission (SF) rates are investigated in covalently linked dimers of tetracene. Using covalent linkers, relative orientation of the individual chromophores can be controlled, maximizing the rates of SF. Structures with coplanar and staggered arrangements of tetracene moieties are considered. The electronic structure calculations and three-state kinetic model for SF rates provide explanations for experimentally observed low SF yields in coplanar dimers and efficient SF in staggered dimers. The calculations illuminate the role of the excimer formation in SF process. The structural relaxation in the S1 state leads to the increased rate of the multi-exciton (ME) state formation, but impedes the second step, separation of the ME state into independent triplets. The slower second step reduces SF yield by allowing other processes, such as radiationless relaxation, to compete with triplet generation. The calculations of electronic couplings also suggest an increased rate of radiationless relaxation at the excimer geometries. Thus, the excimer serves as a trap of the ME state. The effect of covalent linkers on the electronic factors and SF rates is investigated. In all considered structures, the presence of the linker leads to larger couplings, however, the effect on the overall rate is less straightforward, since the linkers generally result in less favorable energetics. This complex behavior once again illustrates the importance of integrative approaches that evaluate the overall rate, rather than focusing on specific electronic factors such as energies or couplings.

  1. Mercury mass measurement in fluorescent lamps via neutron activation analysis

    NASA Astrophysics Data System (ADS)

    Viererbl, L.; Vinš, M.; Lahodová, Z.; Fuksa, A.; Kučera, J.; Koleška, M.; Voljanskij, A.

    2015-11-01

    Mercury is an essential component of fluorescent lamps. Not all fluorescent lamps are recycled, resulting in contamination of the environment with toxic mercury, making measurement of the mercury mass used in fluorescent lamps important. Mercury mass measurement of lamps via instrumental neutron activation analysis (NAA) was tested under various conditions in the LVR-15 research reactor. Fluorescent lamps were irradiated in different positions in vertical irradiation channels and a horizontal channel in neutron fields with total fluence rates from 3×108 cm-2 s-1 to 1014 cm-2 s-1. The 202Hg(n,γ)203Hg nuclear reaction was used for mercury mass evaluation. Activities of 203Hg and others induced radionuclides were measured via gamma spectrometry with an HPGe detector at various times after irradiation. Standards containing an Hg2Cl2 compound were used to determine mercury mass. Problems arise from the presence of elements with a large effective cross section in luminescent material (europium, antimony and gadolinium) and glass (boron). The paper describes optimization of the NAA procedure in the LVR-15 research reactor with particular attention to influence of neutron self-absorption in fluorescent lamps.

  2. CALiPER Benchmark Report: Performance of T12 and T8 Fluorescent Lamps and Troffers and LED Linear Replacement Lamps

    SciTech Connect

    Myer, M. A.; Paget, M. L.; Lingard, R. D.

    2009-01-01

    This report examines standard fluorescent lamps, the recessed troffers they are commonly used in, and available LED replacements for T12 and T8 fluorescent lamps and their application in fluorescent troffers.

  3. Lysosome-associated protein 1 (LAMP-1) and lysosome-associated protein 2 (LAMP-2) in a larger family carrier of Fabry disease.

    PubMed

    Pereira, Ester M; do Monte, Semiramis J H; do Nascimento, Fernando F; de Castro, Jose A F; Sousa, Jackeline L M; Filho, Henrique C S A L C; da Silva, Raimundo N; Labilloy, Anatália; Monte Neto, José T; da Silva, Adalberto S

    2014-02-15

    This study investigated the potential relationship between the expression levels of lysosome-associated membrane proteins (LAMP) 1 and 2 and responses to enzyme replacement therapy (ERT) in the members of a single family with Fabry disease (FD). LAMP levels were assessed by flow cytometry in leukocytes from 17 FD patients who received an eight-month course of ERT course and 101 healthy individuals. We found that phagocytic cells from the FD patients had higher expression levels of both LAMP-1 and LAMP-2, relative to the levels in phagocytes from the healthy controls (p=0.001). Furthermore, the LAMP-1 and LAMP-2 levels in phagocytes from the FD carriers continuously decreased with ERT administration to reach levels similar to those in healthy controls. We suggest that LAMP-1 and LAMP-2 could be used as additional markers with which to assess ERT effectiveness in FD.

  4. Valacyclovir for the prevention of recurrent herpes simplex virus eye disease after excimer laser photokeratectomy.

    PubMed Central

    Asbell, P A

    2000-01-01

    PURPOSE: A variety of factors have been reported as inducing the reactivation of latent herpes simplex virus (HSV), among them stress, trauma, and UV radiation. Excimer laser photorefractive keratectomy (PRK) is a surgical procedure utilizing a 193 nm ultraviolet light to alter the curvature of the cornea and hence correct vision. Reactivation of ocular herpes simplex keratitis following such excimer laser PRK has been reported. All published cases of HSV reactivation following excimer laser treatment in humans are reviewed. The present study evaluates whether stress, trauma of the corneal de-epithelialization prior to the laser, or the excimer laser treatment itself to the stromal bed induces this ocular reactivation of the latent HSV, and whether a systemic antiviral agent, valacyclovir, would prevent such laser PRK-induced reactivation of the HSV. METHODS: Forty-three normal 1.5- to 2.5-kg New Zealand white rabbits were infected on the surface of the cornea with HSV-1, strain RE. The animals were monitored until resolution, and then all animals were divided into 5 treatment groups: (1) de-epithelialization only, intraperitoneal (i.p.) saline for 14 days; (2) de-epithelialization plus laser, i.p. saline for 14 days; (3) de-epithelialization plus laser, valacyclovir 50 mg/kg per day i.p. for 14 days; (4) de-epithelialization plus laser, valacyclovir 100 mg/kg per day i.p. for 14 days; (5) de-epithelialization plus laser, valacyclovir 150 mg/kg per day i.p. for 14 days. Animals were evaluated in a masked fashion by clinical examination biweekly and viral cultures biweekly through day 28. RESULTS: The reactivation rates were as follows: group 1, 0%; group 2, 67%; group 3, 50%; group 4, 17%; and group 5, 0%. Viral titers were negative in animals that had no reactivation but persistently positive in those that had reactivation (day 6 through day 28). CONCLUSIONS: Excimer laser (193 nm) treatment can trigger reactivation of ocular herpes disease (67%) and viral

  5. Red phosphors for use in high CRI fluorescent lamps

    DOEpatents

    Srivastava, Alok; Comanzo, Holly; Manivannan, Vankatesan; Setlur, Anant Achyut

    2005-11-15

    Novel red emitting phosphors for use in fluorescent lamps resulting in superior color rendering index values compared to conventional red phosphors. Also disclosed is a fluorescent lamp including a phosphor layer comprising blends of one or more of a blue phosphor, a blue-green phosphor, a green phosphor and a red a phosphor selected from the group consisting of SrY.sub.2 O.sub.4 :Eu.sup.3+, (Y,Gd)Al.sub.3 B.sub.4 O.sub.12 :Eu.sup.3+, and [(Y.sub.1-x-y-m La.sub.y)Gd.sub.x ]BO.sub.3 :Eu.sub.m wherein y<0.50 and m=0.001-0.3. The phosphor layer can optionally include an additional deep red phosphor and a yellow emitting phosphor. The resulting lamp will exhibit a white light having a color rendering index of 90 or higher with a correlated color temperature of from 2500 to 10000 Kelvin. The use of the disclosed red phosphors in phosphor blends of lamps results in high CRI light sources with increased stability and acceptable lumen maintenance over the course of the lamp life.

  6. Piecewise nonlinear regression: a statistical look at lamp performance

    NASA Astrophysics Data System (ADS)

    Halverson, Galen D.; Hamilton, M. Guyene

    1996-09-01

    Ultraviolet (UV) thickness measurement equipment has little room for variation when determining ultra thin films which are 70 angstroms or less. High lamp performance is critical for measurement validity. A quality conscious semiconductor must have data to verify a vendor claim of 'The lamp performance will perform with no degradation for up to (xxx) hours of normal operation.' In this article we review a real case where data was collected and examined to answer important questions about lamp performance in UV measurement equipment. How long could a lamp be used before performance degraded enough to necessitate a lamp replacement? This article will illustrate how we used standards and actual measurements to collect data for this study. Plots are included showing actual collected data followed by a discussion of alternative methods for statistical examination of the data. This discussion will include an illustration of an original and useful statistical approach for determining the point in time when degradation is noticeable. The method for examining data begins with a well known but not too frequency used concept known as piecewise linear regression with a fixed point of join. Then we enhance the method by turning the join point into a variable that is 'floated' using an iterative non-linear regression approach.

  7. Thomson scattering on high pressure Hg discharge lamps

    NASA Astrophysics Data System (ADS)

    Zhu, X.; de Vries, N.; Kieft, E. R.; van der Mullen, J. J. A. M.; Haverlag, M.

    2005-06-01

    Thomson scattering (TS) experiments have been performed on high-pressure Hg discharge lamps. These lamps were filled with different amounts of Hg (15, 30, 50 and 70 mg) and were operating at different powers (150, 200 and 240 W) with a square-wave ballast. As in the previous studies (Zhu X et al 2004 J. Phys. D: Appl. Phys. 37 736-43) a triple grating spectrograph was used to suppress the false stray light and Rayleigh scattered photons. This set-up had to be modified for this special application. The collective TS spectra have been fitted using both a calibration using Raman scattering and a form fitting procedure. It was found that the electron temperature fluctuates around a certain value that seems rather constant in the central region. The value of electron temperature (Te) varies between 5500 and 7600 K in the central region (r <= 0.3 R). The spatial-averaged Te value increases with the lamp power. The electron density was found to be of the order of 1021 m-3 which is high at the centre and decreases as r increases. The ne value also increases with the lamp power. Moreover the results of TS are compared with those from x-ray absorption measurement. The comparison shows that the plasmas in such lamps are not in local thermal equilibrium in the sense that T_e\

  8. Spectroscopic imaging of metal halide high-intensity discharge lamps

    NASA Astrophysics Data System (ADS)

    Bonvallet, Geoffrey A.

    The body of this work consists of three main research projects. An optical- and near-ultraviolet-wavelength absorption study sought to determine absolute densities of ground and excited level Sc atoms, ground level Sc + ions, and ground level Na atoms in a commercial 250 W metal halide high intensity discharge lamp during operation. These measurements also allowed the determination of the arc temperature and absolute electron density as functions of radius. Through infrared emission spectroscopy, relative densities of sodium and scandium were determined as functions of radius. Using the absolute densities gained from the optical experiment, these relative densities were calibrated. In addition, direct observation of the infrared emission allowed us to characterize the infrared power losses of the lamp. When considered as a fraction of the overall power consumption, the near-infrared spectral power losses were not substantial enough to warrant thorough investigation of their reduction in these lamps. The third project was an attempt to develop a portable x-ray diagnostic experiment. Two-dimensional spatial maps of the lamps were analyzed to determine absolute elemental mercury densities and the arc temperature as a function of radius. Two methods were used to improve the calibration of the density measurements and to correct for the spread in x-ray energy: known solutions of mercury in nitric acid, and an arc lamp which was uniformly heated to evaporate the mercury content. Although many complexities arose in this experiment, its goal was successfully completed.

  9. A simple method for panretinal imaging with the slit lamp.

    PubMed

    Gellrich, Marcus-Matthias

    2016-12-01

    Slit lamp biomicroscopy of the retina with a convex lens is a key procedure in clinical practice. The methods presented enable ophthalmologists to adequately image large and peripheral parts of the fundus using a video-slit lamp and freely available stitching software. A routine examination of the fundus with a slit lamp and a +90 D lens is recorded on a video film. Later, sufficiently sharp still images are identified on the video sequence. These still images are imported into a freely available image-processing program (Hugin, for stitching mosaics together digitally) and corresponding points are marked on adjacent still images with some overlap. Using the digital stitching program Hugin panoramic overviews of the retina can be built which can extend to the equator. This allows to image diseases involving the whole retina or its periphery by performing a structured fundus examination with a video-slit lamp. Similar images with a video-slit lamp based on a fundus examination through a hand-held non-contact lens have not been demonstrated before. The methods presented enable those ophthalmologists without high-end imaging equipment to monitor pathological fundus findings. The suggested procedure might even be interesting for retinological departments if peripheral findings are to be documented which might be difficult with fundus cameras.

  10. Multiple-lamp illumination system for projection displays

    NASA Astrophysics Data System (ADS)

    Vanderwerf, Dennis F.

    1996-03-01

    This paper describes a diascopic projection system that efficiently combines and integrates the output from multiple light sources. The images of these light sources are superposed at a common focus in the projection lens, resulting in a projected screen brightness considerably greater than that produced by a single lamp of equivalent wattage. The illumination system consists of a series of collimating and converging plastic Fresnel lenses, and a linear beam- integrating micro-prismatic element. Glass anamorphic condenser optics are also used. The optics can be cascaded, and the design requirements of a four-lamp system is described. The experimental results from a laboratory developed overhead projection system using dual tungsten-halogen lamps is discussed.

  11. A novel solution for LED wall lamp design and simulation

    NASA Astrophysics Data System (ADS)

    Ge, Rui; Hong, Weibin; Li, Kuangqi; Liang, Pengxiang; Zhao, Fuli

    2014-11-01

    The model of the wall washer lamp and the practical illumination application have been established with a new design of the lens to meet the uniform illumination demand for wall washer lamp based on the Lambertian light sources. Our secondary optical design of freeform surface lens to LED wall washer lamp based on the conservation law of energy and Snell's law can improve the lighting effects as a uniform illumination. With the relationship between the surface of the lens and the surface of the target, a great number of discrete points of the freeform profile curve were obtained through the iterative method. After importing the data into our modeling program, the optical entity was obtained. Finally, to verify the feasibility of the algorithm, the model was simulated by specialized software, with both the LED Lambertian point source and LED panel source model.

  12. Investigating antennas as ignition aid for automotive HID lamps

    NASA Astrophysics Data System (ADS)

    Bergner, A.; Engelhardt, M.; Bienholz, S.; Ruhrmann, C.; Hoebing, T.; Groeger, S.; Mentel, J.; Awakowicz, P.

    2015-01-01

    This paper considers the ignition of mercury-free high-intensity discharge (HID) lamps for car headlights. Due to safety reasons, these lamps need to have a fast run-up phase which is ensured, amongst other things, by a high Xe pressure of roughly 15 bar (cold) in the discharge vessel. The high Xe pressure causes an increased ignition voltage compared with former mercury-containing automotive HID lamps or low-pressure lamps used for general-lighting applications. The increase in ignition voltage can be limited if the electric field in front of the electrodes is raised by an uplifting of the electrical conductivity along the outer wall of the inner bulb either by a conductive layer on its surface or by a dielectric barrier discharge (DBD) within the outer bulb. This paper considers on the one hand conventional antennas deposited by physical vapour deposition (PVD) and on the other hand a combination of these antennas with a DBD within the outer-bulb operated in 100 mbar Ar as ignition aids. In both cases the antenna potential and antenna width are varied. Additionally, the effects of antenna thickness and antenna material are investigated. The ignition voltage, ignition current and light emission during ignition are measured on a nanosecond timescale. Furthermore, for the very first time, the ignition process is recorded in four consecutive intensified charge-coupled device images using a high-speed camera system with a time resolution in the range of nanoseconds. It was found that antennas strongly reduce the ignition voltage of automotive HID lamps. Active antennas reduce the ignition voltage significantly more than passive antennas, proportional to the conductance of the antenna. Combining conventional antennas with an outer-bulb discharge reduces the ignition voltage from 19 kV without any ignition aid to the intrinsic ignition voltage of the lamp below 10 kV, in the best case.

  13. XeCl excimer laser with new prism resonator configurations and its performance characteristics

    SciTech Connect

    Benerji, N. S. E-mail: bsingh@rrcat.gov.in; Singh, A.; Varshnay, N.; Singh, Bijendra E-mail: bsingh@rrcat.gov.in

    2015-07-15

    New resonator cavity configurations, namely, the prism resonator and unstable prism resonator, are demonstrated for the first time in an excimer (XeCl) laser with interesting and novel results. High misalignment tolerance ∼50 mrad is achieved with considerably reduced beam divergence of less than ∼1 mrad without reduction in output power capabilities of the laser. The misalignment tolerance of ∼50 mrad is a dramatic improvement of ∼25 times compared to ∼2 mrad normally observed in standard excimer laser with plane-plane cavity. Increase in depth of focus from 3 mm to 5.5 mm was also achieved in case of prism resonator configuration with an improvement of about 60%. Unstable prism resonator configuration is demonstrated here in this paper with further reduction in beam divergence to about 0.5 mrad using plano-convex lens as output coupler. The misalignment tolerance in case of unstable prism resonator was retained at about 30 mrad which is a high value compared to standard unstable resonators. The output beam spot was completely filled with flat-top profile with prism resonator configurations, which is desired for various material processing applications. Focusing properties and beam divergence in case of prism resonator have been investigated using SEM (scanning electron microscope) images. SEM images of the focused spot size (∼20 μm holes) on metal sheet indicate beam divergence of about 0.05 mrad which is about 1.5 times diffraction limit. Energy contained in this angle is thus sufficient for micro-machining applications. Clean and sharp edges of the micro-holes show high pointing stability with multiple shot exposures. Such characteristics of the excimer laser system will be extremely useful in micro-machining and other field applications.

  14. Cyclic up-regulation fluorescence of pyrene excimer for studying polynucleotide kinase activity based on dual amplification.

    PubMed

    Xu, Jing; Gao, Yanfang; Li, Baoxin; Jin, Yan

    2016-06-15

    Due to its important biological and clinical roles of polynucleotide kinase (PNK), accurate monitoring of PNK activity and inhibition is highly desirable. Herein, a homogeneous and sensitive fluorescence assay has been proposed for the detection of PNK activity by integrating target recycling signal amplification of DNA toehold strand displacement reaction (TSDR) with gamma-cyclodextrin (γ-CD) enhancement of pyrene excimer. A label-free hairpin DNA1 (H1) and two singly pyrene-labelled DNA, H2 and H3, are designed. Accompanying the occurrence of the efficient enzyme reactions, namely phosphorylation-actuated λ exonuclease reaction, a single-stranded DNA as a trigger DNA (tDNA) of TSDR can be released from H1. Then, tDNA drives circulatory interactions between H2 and H3 to continuously form H2/H3 duplex, resulting in formation of pyrene excimer and a "turn on" fluorescence signal of pyrene excimer. Furthermore, the fluorescence of pyrene excimer is further amplified by introducing gamma-cyclodextrin (γ-CD), which can regulate the space proximity of two pyrene molecules. Thus, TSDR-induced cyclic formation of pyrene excimer and γ-CD enhancement can specifically up-regulate the fluorescence of pyrene excimer for detection of PNK activity, the detection limit is 9.3 × 10(-5)UmL(-1), which is superior to those of most existing approaches. Moreover, the proposed strategy can also be successfully utilized to study inhibition efficiency of different PNK inhibitors as well. Therefore, a dual amplification approach is provided for nucleic acid phosphorylation related researches.

  15. LAMP-3 (Lysosome-Associated Membrane Protein 3) Promotes the Intracellular Proliferation of Salmonella typhimurium

    PubMed Central

    Lee, Eun-Ju; Park, Kwan-Sik; Jeon, In-Sook; Choi, Jae-Woon; Lee, Sang-Jeon; Choy, Hyun E.; Song, Ki-Duk; Lee, Hak-Kyo; Choi, Joong-Kook

    2016-01-01

    Lysosomes are cellular organelles containing diverse classes of catabolic enzymes that are implicated in diverse cellular processes including phagocytosis, autophagy, lipid transport, and aging. Lysosome-associated membrane proteins (LAMP-1 and LAMP-2) are major glycoproteins important for maintaining lysosomal integrity, pH, and catabolism. LAMP-1 and LAMP-2 are constitutively expressed in Salmonella-infected cells and are recruited to Salmonella-containing vacuoles (SCVs) as well as Salmonella-induced filaments (Sifs) that promote the survival and proliferation of the Salmonella. LAMP-3, also known as DC-LAMP/CD208, is a member of the LAMP family of proteins, but its role during Salmonella infection remains unclear. DNA microarray analysis identified LAMP-3 as one of the genes responding to LPS stimulation in THP-1 macrophage cells. Subsequent analyses reveal that LPS and Salmonella induced the expression of LAMP-3 at both the transcriptional and translational levels. Confocal Super resolution N-SIM imaging revealed that LAMP-3, like LAMP-2, shifts its localization from the cell surface to alongside Salmonella. Knockdown of LAMP-3 by specific siRNAs decreased the number of Salmonella recovered from the infected cells. Therefore, we conclude that LAMP-3 is induced by Salmonella infection and recruited to the Salmonella pathogen for intracellular proliferation. PMID:27329040

  16. LAMP-3 (Lysosome-Associated Membrane Protein 3) Promotes the Intracellular Proliferation of Salmonella typhimurium.

    PubMed

    Lee, Eun-Ju; Park, Kwan-Sik; Jeon, In-Sook; Choi, Jae-Woon; Lee, Sang-Jeon; Choy, Hyun E; Song, Ki-Duk; Lee, Hak-Kyo; Choi, Joong-Kook

    2016-07-01

    Lysosomes are cellular organelles containing diverse classes of catabolic enzymes that are implicated in diverse cellular processes including phagocytosis, autophagy, lipid transport, and aging. Lysosome-associated membrane proteins (LAMP-1 and LAMP-2) are major glycoproteins important for maintaining lysosomal integrity, pH, and catabolism. LAMP-1 and LAMP-2 are constitutively expressed in Salmonella-infected cells and are recruited to Salmonella-containing vacuoles (SCVs) as well as Salmonella-induced filaments (Sifs) that promote the survival and proliferation of the Salmonella. LAMP-3, also known as DC-LAMP/CD208, is a member of the LAMP family of proteins, but its role during Salmonella infection remains unclear. DNA microarray analysis identified LAMP-3 as one of the genes responding to LPS stimulation in THP-1 macrophage cells. Subsequent analyses reveal that LPS and Salmonella induced the expression of LAMP-3 at both the transcriptional and translational levels. Confocal Super resolution N-SIM imaging revealed that LAMP-3, like LAMP-2, shifts its localization from the cell surface to alongside Salmonella. Knockdown of LAMP-3 by specific siRNAs decreased the number of Salmonella recovered from the infected cells. Therefore, we conclude that LAMP-3 is induced by Salmonella infection and recruited to the Salmonella pathogen for intracellular proliferation.

  17. Very high efficacy electrodeless high intensity discharge lamps

    DOEpatents

    Johnson, Peter D.

    1987-01-01

    An electrodeless arc lamp comprises an outer jacket hermetically sealing and thermally protecting an arc tube inside which has an upwardly convex bottom center section. The absence of chemically reactive electrode material makes it possible to use metal halides other than iodides. The tube contains chlorides, bromides or a mixture thereof of scandium and sodium in a nearly equimolar relationship in addition to mercury and an inert gas. Good color balance can be obtained at reduced reservoir temperature and with less power loss. Reduction in wall temperature makes it possible to attain longer lamp life.

  18. Very high efficacy electrodeless high intensity discharge lamps

    DOEpatents

    Johnson, P.D.

    1985-10-03

    An electrodeless arc lamp comprises an outer jacket hermetically sealing and thermally protecting an arc tube inside which has an upwardly convex bottom center section. The absence of chemically reactive electrode material makes it possible to use metal halides other than iodides. The tube contains chlorides, bromides or a mixture thereof of scandium and sodium in a nearly equimolar relationship in addition to mercury and an inert gas. Good color balance can be obtained at reduced reservoir temperature and with less power loss. Reduction in wall temperature makes it possible to attain longer lamp life.

  19. Amorphous and excimer laser annealed SiC films for TFT fabrication

    NASA Astrophysics Data System (ADS)

    García, B.; Estrada, M.; Albertin, K. F.; Carreño, M. N. P.; Pereyra, I.; Resendiz, L.

    2006-02-01

    The characteristics of hydrogenated amorphous silicon carbide films prepared by PECVD and crystallized by KrF UV excimer laser annealing (ELA), for different annealing conditions, are studied to determine particulate size, surface roughness, band gap and resistivity in order to apply them to TFTs fabrication. Raman spectra for ELA SiC films indicate the presence of 6H-SiC polytype together with Si and C crystallites. We also describe the fabrication process to obtain a-Si 1- xC x:H TFTs and ELA TFTs on the same wafer, comparing their output and transfer characteristics.

  20. ArF excimer laser microprocessing of polymer optical fibers for photonic sensor applications

    NASA Astrophysics Data System (ADS)

    Athanasekos, Loukas; Vasileiadis, Miltiadis; El Sachat, Alexandros; Vainos, Nikolaos A.; Riziotis, Christos

    2015-01-01

    A study of polymer optical fiber microstructuring by use of deep ultraviolet excimer laser radiation at 193 nm wavelength is performed. The ablation characteristics of the fiber cladding and core materials are analyzed comparatively. The laser irradiation effects are dynamically studied by on-line monitoring of the laser ablation induced waveguiding losses, the latter being correlated with the spatial structuring parameters. The fiber surface is modified to incorporate cavities, which are subsequently employed as sensitive material receptors for the development of customized photonic sensors. The sensing capability of the microstructured plastic optical fibers is demonstrated by ammonia and humidity detection.

  1. Excimer laser-induced diamond graphitization for high-energy nuclear applications

    NASA Astrophysics Data System (ADS)

    Alemanno, E.; Caricato, A. P.; Chiodini, G.; Martino, M.; Ossi, P. M.; Spagnolo, S.; Perrino, R.

    2013-12-01

    In this work, we have studied the structure and the morphology of a graphite layer induced on the surface of a polycrystalline thermal grade CVD diamond by focusing a pulsed excimer laser operating at KrF (wavelength 248 nm) and ArF (wavelength 193 nm) mixtures. By micro-Raman and photoluminescence spectroscopies, as well as scanning electron microscopy, we reported the synthesis of a turbostratic t-graphite layer after irradiation with ArF laser. By contrast, irradiating with a KrF laser beam, we obtained a disordered graphite layer with 10 laser shots, while 200 consecutive laser pulses resulted in target ablation.

  2. Spectrally narrowed lasing of a self-injection KrF excimer laser

    NASA Astrophysics Data System (ADS)

    Shimada, Yasuhiro; Wani, Koichi; Miki, Tadaaki; Kawahara, Hidehito; Mimasu, Mutsumi; Ogata, Yoshiro

    1990-08-01

    Spectrally nantwed lasing of a KrF excimer laser has teen ahieved by a self-injection technique using abeam splitter for power extraction aixi intravity etalons for spectral-narrowing. The laser cavity is divithi into an amplifying branch aix! a spectralnarrowing branch. The spectral bandwidth was narrowed to <3pm FWHM with air-sed etalons placed in the spectral-narrowing branch. A laser propagation model was intrOdUced for describing the laser intensity traveling in the laser cavity. The calculated intensityincident onthe intracavityetalons wassmaller thanthat in theconventional Fabry-Perotcavity withplane-parallel mirrors.

  3. Green synthesis of selenium nanoparticles by excimer pulsed laser ablation in water

    NASA Astrophysics Data System (ADS)

    Van Overschelde, O.; Guisbiers, G.; Snyders, R.

    2013-10-01

    Pure selenium nanoparticles were successfully synthesized by Liquid Phase - Pulsed Laser Ablation (LP-PLA) in de-ionized water. Excimer laser (248 nm) operating at low fluence (F ˜ 1 J/cm2) was used to generate colloidal solutions of selenium nanoparticles. The obtained selenium nanoparticles were characterized by UV-visible spectroscopy, Raman spectroscopy, Dynamic Light Scattering, and Transmission Electron Microscopy. We describe the multi-modal size distributions generated and use the centrifugation method to isolate the smallest nanoparticles (˜60 nm in diameter).

  4. Error analysis of DIAL measurements of ozone by a Shuttle excimer lidar

    NASA Technical Reports Server (NTRS)

    Uchino, Osamu; Mccormick, M. Patrick; Mcmaster, Leonard R.; Swissler, Thomas J.

    1986-01-01

    Attention is given to an error analysis of DIAL measurements of stratospheric ozone from the Space Shuttle. It is shown that a transmitter system consisting of a KrF excimer laser pumping gas cells of H2 or D2 producing output wavelengths in the near UV is useful for the measurement of ozone in a 15-50-km altitude range. It is noted that for increased levels of stratospheric aerosols experienced after violent volcanic eruptions, the relative uncertainties of ozone densities will be large in the region below about 24 km.

  5. Finite element simulation for ultraviolet excimer laser processing of patterned Si/SiGe/Si(100) heterostructures

    SciTech Connect

    Conde, J. C.; Chiussi, S.; Gontad, F.; Gonzalez, P.; Martin, E.; Serra, C.

    2010-07-05

    Ultraviolet (UV) Excimer laser assisted processing is an alternative strategy for producing patterned silicon germanium heterostructures. We numerically analyzed the effects caused by pulsed 193 Excimer laser radiation impinging on patterned amorphous hydrogenated silicon (a-Si:H) and germanium (a-Ge:H) bilayers deposited on a crystalline silicon substrate [Si(100)]. The proposed two dimensional axisymmetric numerical model allowed us to estimate the temperature and concentration gradients caused by the laser induced rapid melting and solidification processes. Energy density dependence of maximum melting depth and melting time evolution as well as three dimensional temperature and element distribution have been simulated and compared with experimentally obtained results.

  6. Frequent Questions About EPA's Mercury Lamp Drum-Top Crusher Study

    EPA Pesticide Factsheets

    Frequent Questions such as Why did we do the Mercury Lamp Drum-Top Crusher Study?, Should drum-top crushers (DTCs) be used in the management of fluorescent lamps?, Are drum-top crushers (DTCs) safe to use?

  7. Study on the structures and illumination characteristics of Chinese ancient oil lamps

    NASA Astrophysics Data System (ADS)

    Zhu, Zhiqiang; Zhan, Qingxuan

    2006-01-01

    Chinese ancient firelight lighting had a long history in which developed technologies were applied. The paper concerns itself with a study of Chinese ancient firelight lighting lamps, including the structures and illuminating characteristics of ancient oil lamps.

  8. 40 CFR 426.120 - Applicability; description of the incandescent lamp envelope manufacturing subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... incandescent lamp envelope manufacturing subcategory. 426.120 Section 426.120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Incandescent Lamp Envelope Manufacturing Subcategory § 426.120...

  9. 40 CFR 426.120 - Applicability; description of the incandescent lamp envelope manufacturing subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... incandescent lamp envelope manufacturing subcategory. 426.120 Section 426.120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Incandescent Lamp Envelope Manufacturing Subcategory § 426.120...

  10. 40 CFR 426.120 - Applicability; description of the incandescent lamp envelope manufacturing subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... incandescent lamp envelope manufacturing subcategory. 426.120 Section 426.120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Incandescent Lamp Envelope Manufacturing Subcategory § 426.120 Applicability; description of...

  11. 40 CFR 426.120 - Applicability; description of the incandescent lamp envelope manufacturing subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... incandescent lamp envelope manufacturing subcategory. 426.120 Section 426.120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Incandescent Lamp Envelope Manufacturing Subcategory § 426.120...

  12. 40 CFR 426.120 - Applicability; description of the incandescent lamp envelope manufacturing subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... incandescent lamp envelope manufacturing subcategory. 426.120 Section 426.120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Incandescent Lamp Envelope Manufacturing Subcategory § 426.120 Applicability; description of...

  13. 78 FR 24233 - Certain Dimmable Compact Fluorescent Lamps and Products Containing Same: Notice of Institution of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-24

    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Certain Dimmable Compact Fluorescent Lamps and Products Containing Same: Notice of Institution of... importation of certain dimmable compact fluorescent lamps (``CFLs'') and products containing the same by...

  14. The Effects of Lamp Spectral Distribution on Sky Glow over Observatories

    NASA Astrophysics Data System (ADS)

    Luginbuhl, C. B.; Boley, P. A.; Davis, D. R.; Duriscoe, D. M.

    2015-03-01

    Using a wavelength-generalized version of the Garstang (1991) model, we evaluate overhead sky glow as a function of distance up to 300 km, from a variety of lamp types, including common gas discharge lamps and several types of LED lamps. We conclude for both professional, and especially cultural (visual), astronomy, that low-pressure sodium and narrow-spectrum amber LED lamps cause much less sky glow than all broad-spectrum sources.

  15. Ablation of poly(methyl methacrylate) and poly(2-hydroxyethyl methacrylate) by 308, 222 and 193 nm excimer-laser radiation

    NASA Astrophysics Data System (ADS)

    Costela, A.; Figuera, J. M.; Florido, F.; García-Moreno, I.; Collar, E. P.; Sastre, R.

    1995-03-01

    Data on the ablation of Poly(Methyl MetAcylate) (PMMA) and Poly(2-Hydroxyethyl MetAcylate) (PHEMA) with 0%, 1% and 20% of Ethylene Glycol DiMethAcrylate (EGDMA) as crosslinking monomer by 193, 222 and 308 nm laser radiation are presented. Direct photoetching of PMMA at 308 nm is demonstrated for laser fluences ranging from 2 to 18 J/cm2. The ablation rate of PHEMA is lower than the corresponding to PMMA and decreases when the amount of EGDMA increases. The determination of the absorbed energy density required to initiate significant ablation suggests that the photoetching mechanism is similar for all the polymers studied and is a function of the irradiation wavelength. The Beer-Lambert law, the Srinivasan, Smrtic and Babu (SSB) theory and the kinetic model of the moving interface are used to analyze the experimental results. It is shown that only the moving interface theory fits well the etch rate for all the selected polymers at the three radiation wavelengths.

  16. 5. VIEW OF THE LAMP HOUSE LOOKING EAST. DECORATIVE BRICK ...

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

    5. VIEW OF THE LAMP HOUSE LOOKING EAST. DECORATIVE BRICK CORBELING AND PILASTERS DIVIDE THE BAYS. BRICK CORBELING ACCENTS THE EAVES. CONCRETE LINTELS ABOVE THE WINDOW OPENINGS PROVIDE ADDITIONAL DETAILING. - Tower Hill No. 2 Mine, Approximately 0.47 mile Southwest of intersection of Stone Church Road & Township Route 561, Hibbs, Fayette County, PA

  17. 15. VIEW, LOOKING NORTH, OF THE GENERATOR HOUSE. THE LAMP ...

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

    15. VIEW, LOOKING NORTH, OF THE GENERATOR HOUSE. THE LAMP HOUSE CAN BE SEEN IN THE BACKGROUND OF THE PHOTO. - Tower Hill No. 2 Mine, Approximately 0.47 mile Southwest of intersection of Stone Church Road & Township Route 561, Hibbs, Fayette County, PA

  18. 21 CFR 866.2600 - Wood's fluorescent lamp.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Wood's fluorescent lamp. 866.2600 Section 866.2600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2600 Wood's...

  19. 21 CFR 866.2600 - Wood's fluorescent lamp.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wood's fluorescent lamp. 866.2600 Section 866.2600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2600 Wood's...

  20. 21 CFR 866.2600 - Wood's fluorescent lamp.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Wood's fluorescent lamp. 866.2600 Section 866.2600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2600 Wood's...

  1. 21 CFR 866.2600 - Wood's fluorescent lamp.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Wood's fluorescent lamp. 866.2600 Section 866.2600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2600 Wood's...

  2. 21 CFR 866.2600 - Wood's fluorescent lamp.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Wood's fluorescent lamp. 866.2600 Section 866.2600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2600 Wood's...

  3. Calibration and Temperature Profile of a Tungsten Filament Lamp

    ERIC Educational Resources Information Center

    de Izarra, Charles; Gitton, Jean-Michel

    2010-01-01

    The goal of this work proposed for undergraduate students and teachers is the calibration of a tungsten filament lamp from electric measurements that are both simple and precise, allowing to determine the temperature of tungsten filament as a function of the current intensity. This calibration procedure was first applied to a conventional filament…

  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. Photovoltaic Experiment Using Light from a Solar Simulator Lamp.

    ERIC Educational Resources Information Center

    Chow, R. H.

    1980-01-01

    A photovoltaic cell experiment utilizing the convenience of a solar simulating type lamp is described. Insight into the solid state aspect of a solar cell is gained by the student in studying the characteristics, and deducing from them cell parameters and efficiency. (Author/CS)

  6. Very Fast Temperature Measurement with a Thin Lamp Filament

    ERIC Educational Resources Information Center

    G. Calza, Gratton, L. M.; Lopez-Arias, T.; Oss, S.

    2012-01-01

    We construct a thermometer exploiting the electric resistance of the filament of a small lamp used in micro-illumination settings. The instrument may guarantee a response time better than 10 ms, i.e. much faster than commercial thermocouples or other quite expensive devices. This makes our thermometer a useful one in several processes which are…

  7. Miniature Incandescent Lamps as Fiber-Optic Light Sources

    NASA Technical Reports Server (NTRS)

    Tuma, Margaret; Collura, Joe; Helvajian, Henry; Pocha, Michael; Meyer, Glenn; McConaghy, Charles F.; Olsen, Barry L.

    2008-01-01

    Miniature incandescent lamps of a special type have been invented to satisfy a need for compact, rapid-response, rugged, broadband, power-efficient, fiber-optic-coupled light sources for diverse purposes that could include calibrating spectrometers, interrogating optical sensors, spot illumination, and spot heating.

  8. 15. LIGHTING DETAIL ON WAVERLY DRIVE OVERCROSSING HYPERION BOULEVARD. LAMPS ...

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

    15. LIGHTING DETAIL ON WAVERLY DRIVE OVERCROSSING HYPERION BOULEVARD. LAMPS ALSO SEEN IN CA-272-13. LOOKING EAST/SOUTHEAST. - Glendale-Hyperion Viaduct, Spanning Golden State Freeway (I-5) & Los Angeles River at Glendale Boulevard, Los Angeles, Los Angeles County, CA

  9. On the Intensity Profile of Electric Lamps and Light Bulbs

    ERIC Educational Resources Information Center

    Bacalla, Xavier; Salumbides, Edcel John

    2013-01-01

    We demonstrate that the time profile of the light intensity from domestic lighting sources exhibits simple yet interesting properties that foster lively student discussions. We monitor the light intensity of an industrial fluorescent lamp (also known as TL) and an incandescent bulb using a photodetector connected to an oscilloscope. The light…

  10. Optimized elemental analysis of fluorescence lamp shredder waste.

    PubMed

    Hobohm, Julia; Kuchta, Kerstin; Krüger, Oliver; van Wasen, Sebastian; Adam, Christian

    2016-01-15

    Fluorescence lamps contain considerable amounts of rare earth elements (REE). Several recycling procedures for REE recovery from spent lamps have been established. However, despite their economic importance, the respective recycling is scarce so far, with an REE recovery rate of less than 1%. A reliable analysis of REE and other relevant metals like Yttrium is crucial for a thorough and complete recovery process. This applies both to the solid matter and aqueous phase, since most of the recycling processes include wet-chemical steps. We tested seven different reagent mixtures for microwave-assisted digestion of fluorescent lamp shredder, including hydrofluoric acid, perchloric acid, and hydrogen peroxide. We determined the concentrations of 25 of the most relevant rare earth and other trace elements (Al, P, Ti, V, Cr, Fe, Ni, Cu, Ga, Ge, As, Y, Ag, Cd, Sn, Sb, La, Ce, Eu, Gd, Tb, W, Au, Hg, and Pb) in the respective dilutions. Two independent digestions, one a mixture of perchlorid/nitric/hydrofluoric acid and the other aqua regia, showed the highest concentrations of 23 of these elements, excluding only Sn and Tb. The REE concentrations in the tested lamp shredder sample (stated in g/kg) were 10.2 (Y), 12.1 (La), 7.77 (Ce), 6.91 (Eu), 1.90 (Gd), and 4.11 (Tb).

  11. 30 CFR 56.12035 - Weatherproof lamp sockets.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Weatherproof lamp sockets. 56.12035 Section 56.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  12. 30 CFR 56.12035 - Weatherproof lamp sockets.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Weatherproof lamp sockets. 56.12035 Section 56.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  13. 30 CFR 56.12035 - Weatherproof lamp sockets.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Weatherproof lamp sockets. 56.12035 Section 56.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  14. 30 CFR 56.12035 - Weatherproof lamp sockets.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Weatherproof lamp sockets. 56.12035 Section 56.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  15. 30 CFR 56.12035 - Weatherproof lamp sockets.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Weatherproof lamp sockets. 56.12035 Section 56.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  16. Optical properties of lamps with cold emission cathode

    NASA Astrophysics Data System (ADS)

    Kalenik, Jerzy; Czerwosz, ElŻbieta; Biernacki, Krzysztof; Rymarczyk, Joanna; Stepińska, Izabela

    2016-12-01

    A luminescent lamp was constructed and tested. Phosphor excited by electrons is the source of light. The source of electrons is field emission cathode. The cathode is covered with nickel-carbon layer containing carbon nanotubes that enhance electron emission from the cathode. Results of luminance measurements are presented. Luminance is high enough for lighting application.

  17. CALiPER Exploratory Study Retail Replacement Lamps – 2011

    SciTech Connect

    2012-04-02

    In 2010, CALiPER conducted a study on LED replacement lamps found in retail stores. The results were less than satisfactory, and many products were classified as being unlikely to meet consumer expectations. In November 2011, CALiPER purchased a new sample of products for a follow-up study, with the intent of characterizing the progress of this essential market segment.

  18. Direct-current converter for gas-discharge lamps

    NASA Technical Reports Server (NTRS)

    Lutus, P.

    1980-01-01

    Metal/halide and similar gas-discharge lamps are powered from low-voltage dc source using small efficient converter. Converter is useful whenever 60-cycle ac power is not available or where space and weight allocations are limited. Possible applications are offshore platforms, mobile homes, and emergency lighting. Design innovations give supply high reliability and efficiency up to 75 percent.

  19. CALiPER Special Summary Report: Retail Replacement Lamp Testing

    SciTech Connect

    2011-04-01

    CALiPER testing has evaluated many products for commercial lighting markets and found some excellent performers. However, many of these are not available on the retail market. This special testing was undertaken to identify and test solid-state lighting (SSL) replacement lamp products that are available to the general public through retail stores and websites.

  20. Pyrometric cathode temperature measurements in metal halide lamps

    NASA Astrophysics Data System (ADS)

    Schmidt, M.; Schneidenbach, H.; Kettlitz, M.

    2013-10-01

    Time-averaged temperature distributions along the electrodes of vertically operated high-intensity discharge lamps with cylindrical quartz burners filled with mercury and additives of NaI, TlI and DyI3 have been measured. The lamps have been driven by 120 Hz switched-dc currents between 0.4 and 1.78 A and the measurements have been performed during the cathodic phase at the lower electrode. All considered currents are characterized by a diffuse arc attachment. For the correction of disturbing effects the measured distributions have been fitted with solutions of the quasi-one-dimensional and steady-state energy balance of a rod-shaped tungsten cathode. A model of the near-cathode layer in a multi-species plasma has been applied for the determination of the boundary layer characteristics where the work function has been treated as a free parameter. The required plasma component concentrations have been estimated from spectroscopic measurements in the arc column. The fit procedure includes the adjustment of the extension of the lateral arc attachment region which has a distinct impact on the determined tip temperature, power input from the plasma into the cathode and the work function. For the latter the tungsten value has been verified in the pure Hg lamp, but strong deviations result in the case of a TlI admixture. The lamp with DyI3 clearly shows the gas-phase emitter effect of lowering the work function induced by Dy.

  1. 16. A LONGER VIEW OF THE SAME LAMP STANDARD, SHOWING ...

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

    16. A LONGER VIEW OF THE SAME LAMP STANDARD, SHOWING THE OCTAGONAL PEBBLE AGGREGATE SHAFT. - County Line Bridge, Spanning St. Joseph River at State Route 219, 0.6 mile south of U.S. Route 20, Osceola, St. Joseph County, IN

  2. Investigation of breakdown processes in automotive HID lamps

    NASA Astrophysics Data System (ADS)

    Bergner, Andre; Hoebing, Thomas; Ruhrmann, Cornelia; Mentel, Juergen; Awakowicz, Peter

    2011-10-01

    HID lamps are used for applications where high lumen output levels are required. Car headlights are a special field of HID lamp application. For security reasons and lawful regulations these lamps have to have a fast run-up phase and the possibility of hot re-strike. Therefore the background gas pressure amounts to 1.5 MPa xenon. But this high background gas pressure has the disadvantage that the ignition voltage becomes quite high due to Paschen's law. For that reason this paper deals with the investigation of the breakdown process of HID lamps for automotive application. The ignition is investigated by electrical as well as optical methods. Ignition voltage and current are measured on a nanosecond time scale and correlated with simultaneous phase resolved high speed photography done by an ICCD camera. So the ignition process can be observed from the first light emission until to the formation of whole discharge channel. The authors gratefully acknowledge the financial support by BMBF within the European project 'SEEL - Solutions for Energy Efficient Lighting' (FKZ: 13N11265). Furthermore the author would like to thank Philips Lighting (Aachen) for valuable discussions.

  3. 21 CFR 878.4630 - Ultraviolet lamp for dermatologic disorders.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ultraviolet lamp for dermatologic disorders. 878.4630 Section 878.4630 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices §...

  4. 21 CFR 878.4630 - Ultraviolet lamp for dermatologic disorders.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultraviolet lamp for dermatologic disorders. 878.4630 Section 878.4630 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices §...

  5. 21 CFR 878.4630 - Ultraviolet lamp for dermatologic disorders.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ultraviolet lamp for dermatologic disorders. 878.4630 Section 878.4630 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices §...

  6. 21 CFR 878.4630 - Ultraviolet lamp for dermatologic disorders.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ultraviolet lamp for dermatologic disorders. 878.4630 Section 878.4630 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices §...

  7. 21 CFR 878.4630 - Ultraviolet lamp for dermatologic disorders.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ultraviolet lamp for dermatologic disorders. 878.4630 Section 878.4630 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices §...

  8. Liquid Motion Lamp: A Learning-Cycle Approach to Solubility

    ERIC Educational Resources Information Center

    Brown, Sherri L.; Votaw, Nikki L.

    2008-01-01

    The abstract concepts of density and solubility are often difficult for middle-grade students and should be taught within several contexts to provide multiple experiences with the phenomena. To authenticate the learning of these concepts, this article provides instructional guidelines for constructing a liquid motion lamp to engage students in…

  9. Using LAMP Applications to Make Our Library Shine

    ERIC Educational Resources Information Center

    White, Andrew; Balsamo, Joseph

    2005-01-01

    There has been a move afoot in libraries of all kinds to incorporate open source software and applications to better support their rapidly evolving information access and delivery services. There has been particular interest in a specific configuration of open source components?known by the acronym LAMP?that can be used to build fairly complex Web…

  10. The development and progress of XeCl Excimer laser system

    NASA Astrophysics Data System (ADS)

    Zhang, Yongsheng; Ma, Lianying; Wang, Dahui; Zhao, Xueqing; Zhu, Yongxiang; Hu, Yun; Qian, Hang; Shao, Bibo; Yi, Aiping; Liu, Jingru

    2015-05-01

    A large angularly multiplexed XeCl Excimer laser system is under development at the Northwest Institute of Nuclear Technology (NINT). It is designed to explore the technical issues of uniform and controllable target illumination. Short wavelength, uniform and controllable target illumination is the fundamental requirement of high energy density physics research using large laser facility. With broadband, extended light source and multi-beam overlapping techniques, rare gas halide Excimer laser facility will provide uniform target illumination theoretically. Angular multiplexing and image relay techniques are briefly reviewed and some of the limitations are examined to put it more practical. The system consists of a commercial oscillator front end, three gas discharge amplifiers, two electron beam pumped amplifiers and the optics required to relay, encode and decode the laser beam. An 18 lens array targeting optics direct and focus the laser in the vacuum target chamber. The system is operational and currently undergoing tests. The total 18 beams output energy is more than 100J and the pulse width is 7ns (FWHM), the intensities on the target will exceed 1013W/cm2. The aberration of off-axis imaging optics at main amplifier should be minimized to improve the final image quality at the target. Automatic computer controlled alignment of the whole system is vital to efficiency and stability of the laser system, an array of automatic alignment model is under test and will be incorporated in the system soon.

  11. Photo-triggering and secondary electron produced ionization in electric discharge ArF* excimer lasers

    NASA Astrophysics Data System (ADS)

    Xiong, Zhongmin; Kushner, Mark J.

    2011-10-01

    Electric discharge excimer lasers are sustained in multi-atmosphere attaching gas mixtures that are typically preionized to enable a reproducible, uniform glow, which maximizes optical quality and gain. This preionization is often accomplished using UV light produced by a corona discharge within the plasma cavity. To quantify the relationship between corona discharge properties and those of the laser discharge, the triggering of electron avalanche by preionizing UV light in an electric discharge-pumped ArF* excimer laser was numerically investigated using a two-dimensional model. The preionizing UV fluxes were generated by a corona-bar discharge driven by the same voltage pulse as the main discharge sustained in a multi-atmospheric Ne/Ar/Xe/F2 gas mixture. The resulting peak photo-electron density in the inter-electrode spacing is around 108 cm-3, and its distribution is biased toward the UV source. The preionization density increases with increasing dielectric constant and capacitance of the corona bar. The symmetry and uniformity of the discharge are, however, improved significantly once the main avalanche develops. In addition to bulk electron impact ionization, the ionization generated by sheath accelerated secondary electrons was found to be important in sustaining the discharge current at experimentally observed values. At peak current, the magnitude of the ionization by sheath accelerated electrons is comparable to that from bulk electron impact in the vicinity of the cathode.

  12. Quantitative solid sample analysis by ArF excimer laser ablation

    NASA Astrophysics Data System (ADS)

    Delmdahl, Ralph; von Oldershausen, Georg

    2005-06-01

    Reproducible and sensitive elemental analysis of solid samples is a crucial task in areas of geology (e.g. microanalysis of fluid inclusions), material sciences, industrial quality control as well as in environmental, forensic and biological studies. To date the most versatile detection method is mass-spectroscopic multi-element analysis. In order to obtain reproducible results, this requires transferring the solid sample into the gas-phase while preserving the sample's stoichiometric composition. Laser Ablation in combination with inductively coupled plasma-mass spectrometry (LA-ICP-MS) is a proven powerful technique to meet the requirements for reliable solid sample analysis. The sample is laser ablated in an air-tight cell and the aerosol is carried by an inert gas to a micro-wave induced plasma where its constituents are atomized and ionized prior to mass analysis. The 193 nm excimer laser ablation, in particular, provides athermal sample ablation with very precise lateral ablation and controlled depth profiling. The high photon energy and beam homogeneity of the 193 nm excimer laser system avoids elemental fractionation and permits clean ablation of even transmissive solid materials such as carbonates, fluorites and pure quartz.

  13. Effect of excimer laser radiant exposure on uniformity of ablated corneal surface.

    PubMed

    Fantes, F E; Waring, G O

    1989-01-01

    The argon fluoride (193 nm) excimer laser is being used to change the anterior corneal curvature for correction of refractive errors. Uniformity of the surface following laser ablation may play an important role in the rate of epithelial healing and amount and type of stromal scarring. To test the effect of radiant exposure (fluence) on surface smoothness, we ablated rabbit corneas with the 193 nm argon fluoride excimer laser at nine radiant exposures from 50 to 850 mJ/cm2. A total energy of 100 J/cm2 was used for each ablation at a frequency of 1 Hz. Scanning electron microscopy demonstrated progressive improvement of surface smoothness with increasing radiant exposures. Transmission electron microscopy demonstrated no consistent increase in thickness to the surface condensate (pseudomembrane) with increasing radiant exposure. Improvement in surface quality associated with increasing radiant exposures may result from a more uniform depth of ablation per pulse in the corneal lamellae that absorb laser wavelengths differently. Radiant exposures at levels where the depth of ablation is the same regardless of increasing energy densities achieve a more uniform surface because inhomogeneities in the beam and variation in energy from pulse to pulse do not affect the ablation rate.

  14. New excimer laser technique for the correction of strabismus and diplopia

    NASA Astrophysics Data System (ADS)

    Azar, Dimitri T.

    1994-06-01

    We used the ArF excimer laser to determine the feasibility of performing prismatic photoablations in model eyes (plastic spheres simulating the eye), and in rabbit corneas. This would correct diplopia and small angles of deviation, and result in minimal refractive alterations. We modified excimer laser delivery system that achieved the desired corneal contour of prismatic ablations. 193-nm argon fluoride laser was used at fluence of 160 mJ/cm2 and ablation rate 5 Hz. 5.0-mm diameter, 40 um corneal epithelial ablation were followed by 5.0- mm diameter, prismatic photokeratectomy (PPK). We were able to achieve prismatic photoablation of PMMA blocks and lenses. No other refractive changes accompanied the prismatic photoablation of PMMA blocks and lenses. No other refractive changes accompanied the prismatic effect. In rabbits re-epithelialization of the 5-mm ablations was complete by day 3, and corneal haze was not observed by gross examination. Epithelial hyperplasia and subepithelial scarring were noted at the deep edges. PPK holds important therapeutic potential for fine-tuning results of conventional strabismus surgery, and for patients with stable diplopia following nerve palsy and ocular surgery.

  15. Experimental and clinical evaluation of a spectroscopy system for fluorescence-guided excimer laser angioplasty

    NASA Astrophysics Data System (ADS)

    Morguet, Andreas J.; Gabriel, Ruth E.; Buchwald, Arnd B.

    1996-12-01

    This study evaluated a single-laser approach for simultaneous ablation and fluorescence excitation for spectroscopic guidance of laser angioplasty. A spectroscopy system was developed and coupled to a clinical XeCl excimer laser. Ablation of 162 human aortic samples in saline and blood with 45 mJ/mm2 per pulse yielded 676 fluorescence spectra validated histologically. Five types of spectra could be differentiated: atheroma, fibrous plaque, calcified lesion in saline, normal media and calcified lesion in blood. Discriminant analysis prospectively classified 576 validation spectra with a sensitivity between 83.5 and 100 percent and a specificity between 96.8 and 100 percent. Subsequently, the equipment was used in 16 patients for angioplasty of 18 coronary stenoses applying 500 to 1725 pulses with 45 to 60 mJ/mm2 under saline flushing. A total of 783 spectra were recorded and validated by intracoronary ultrasound. Except for the media spectrum, all types of spectra were observed in vivo, too. The predominant sonographic category also prevailed in spectroscopy. In conclusion, using an excimer laser for angioplasty allows combining ablation and fluorescence excitation without a diagnostic laser. Principal types of atherosclerotic lesions and the media can be differentiated spectroscopically with this approach.

  16. Should Tungsten Ribbon Lamps Be Replaced or Not?

    NASA Astrophysics Data System (ADS)

    Matveyev, M. S.; Pokhodun, A. I.; Sild, Yu. A.

    2003-09-01

    Tungsten ribbon lamps are the most frequently used means in the temperature range higher than 800 °C for reproduction and precise transfer of a temperature scale by non-contact methods. Lamps have many advantages: a very high reproducibility, stability and durability; use of a lamp over dozens of years with careful and correct operation; and relative simplicity of operation, storage and transportation. The direct correlation of temperature and current through a ribbon enables us to use the advantages of electrical measurements. At the same time lamps have also a number of negative features. Small deviations from the prescribed procedure can lead to unpredictable changes of the performance of a lamp and, even, to irreversible changes of its parameters. The important factor of the quality of transferring the temperature scale is the propinquity of the transferred temperature to the thermodynamic one. Only this factor guarantees the accuracy and unity of temperature measurements of temperature by instruments applying different principles of operation and various designs. However, this is the quality that the lamps do not possess. Their main drawback is selectivity of radiation stipulated by the spectral dependence of emissivity. That is why it is necessary to replace them with blackbodies, which let us rely completely on the definition of the ITS-90. Several years ago at our institute we started investigations on development of special measuring instruments, in which a sensor was located around a miniature blackbody. The aperture of this blackbody could be used as a standard emitter, which temperature was accurately determined by a resistance thermometer. Applying also a standard pyrometer, we refined the reference function of a platinum resistor in the range between the Ag and Cu fixed points. To extend the temperature range up to 1450 °C to 1500 °C we built an instrument in the form of a miniature blackbody made of Pd which was connected to three platinum wires

  17. Thermal element for maintaining minimum lamp wall temperature in fluorescent fixtures

    DOEpatents

    Siminovitch, M.J.

    1992-11-10

    In a lighting fixture including a lamp and a housing, an improvement is disclosed for maintaining a lamp envelope area at a cooler, reduced temperature relative to the enclosed housing ambient. The improvement comprises a thermal element in thermal communication with the housing extending to and springably urging thermal communication with a predetermined area of the lamp envelope surface. 12 figs.

  18. 49 CFR 393.17 - Lamps and reflectors-combinations in driveaway-towaway operation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... reflectors conforming to the rules in this section. (a) The towing vehicle must be equipped as follows: (1... two tail lamps, one at each side, and two stop lamps, one at each side. (b) Except as provided in... near the rear of the vehicle. (2) On the rear, there must be at least two tail lamps, two stop...

  19. Thermal element for maintaining minimum lamp wall temperature in fluorescent fixtures

    DOEpatents

    Siminovitch, Michael J.

    1992-01-01

    In a lighting fixture including a lamp and a housing, an improvement is disclosed for maintaining a lamp envelope area at a cooler, reduced temperature relative to the enclosed housing ambient. The improvement comprises a thermal element in thermal communication with the housing extending to and springably urging thermal communication with a predetermined area of the lamp envelope surface.

  20. 77 FR 4203 - Energy Conservation Program: Test Procedures for General Service Fluorescent Lamps, General...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-27

    ...On September 14, 2011, the U.S. Department of Energy (DOE) issued a notice of proposed rulemaking (NOPR) to amend the test procedures for general service fluorescent lamps (GSFLs), general service incandescent lamps (GSILs), and incandescent reflector lamps (IRLs). That proposed rulemaking serves as the basis for today's action. DOE is amending its test procedures for GSFLs and GSILs......

  1. 46 CFR 190.05-10 - Chemical storeroom and lamp room construction.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Chemical storeroom and lamp room construction. 190.05-10... VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 190.05-10 Chemical storeroom and lamp room construction. (a) Chemical storerooms, lamp, paint, and oil lockers and similar compartments shall...

  2. LAMP (Loop-mediated isothermal amplification of DNA) - A technique for biotype discrimination in Bemisia tabaci

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Loop-mediated isothermal amplification of DNA (LAMP) can amplify a target DNA sequence at a constant temperature in about 1 hour. LAMP technology has great potential for agricultural applications because of the need for rapid and inexpensive diagnoses. Assays based on LAMP technology are well suited...

  3. 21 CFR 1040.30 - High-intensity mercury vapor discharge lamps.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false High-intensity mercury vapor discharge lamps. 1040...-intensity mercury vapor discharge lamps. (a) Applicability. The provisions of this section apply to any high-intensity mercury vapor discharge lamp that is designed, intended, or promoted for illumination purposes...

  4. 21 CFR 1040.30 - High-intensity mercury vapor discharge lamps.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false High-intensity mercury vapor discharge lamps. 1040...-intensity mercury vapor discharge lamps. (a) Applicability. The provisions of this section apply to any high-intensity mercury vapor discharge lamp that is designed, intended, or promoted for illumination purposes...

  5. 10 CFR 431.322 - Definitions concerning metal halide lamp ballasts and fixtures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Definitions concerning metal halide lamp ballasts and... FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Metal Halide Lamp Ballasts and Fixtures § 431.322 Definitions concerning metal halide lamp ballasts and fixtures. Ballast efficiency means, in the case of...

  6. 75 FR 5544 - Energy Conservation Program: Energy Conservation Standards for Metal Halide Lamp Fixtures: Public...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ... for Metal Halide Lamp Fixtures: Public Meeting and Availability of the Framework Document AGENCY... conservation standards for certain metal halide lamp fixtures. This document announces that the period for... metal halide lamp fixtures and provide docket number EERE-2009-BT-STD-0018 and/or RIN number 1904-...

  7. 10 CFR 429.54 - Metal halide lamp ballasts and fixtures.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Metal halide lamp ballasts and fixtures. 429.54 Section... CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.54 Metal halide lamp ballasts... are applicable to metal halide lamp ballasts; and (2) For each basic model of metal halide...

  8. 10 CFR 429.54 - Metal halide lamp ballasts and fixtures.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Metal halide lamp ballasts and fixtures. 429.54 Section... CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.54 Metal halide lamp ballasts... are applicable to metal halide lamp ballasts; and (2) For each basic model of metal halide...

  9. 10 CFR Appendix B to Subpart S to... - Certification Report for Metal Halide Lamp Ballasts

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Certification Report for Metal Halide Lamp Ballasts B... PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Metal Halide Lamp Ballasts and Fixtures Pt. 431, Subpt. S, App. B Appendix B to Subpart S to Part 431—Certification Report for Metal Halide Lamp...

  10. 10 CFR Appendix A to Subpart S of... - Compliance Statement for Metal Halide Lamp Ballasts

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Compliance Statement for Metal Halide Lamp Ballasts A... PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Metal Halide Lamp Ballasts and Fixtures Pt. 431, Subpt. S, App. A Appendix A to Subpart S of Part 431—Compliance Statement for Metal Halide Lamp...

  11. 10 CFR 429.54 - Metal halide lamp ballasts and fixtures.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Metal halide lamp ballasts and fixtures. 429.54 Section... CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.54 Metal halide lamp ballasts... are applicable to metal halide lamp ballasts; and (2) For each basic model of metal halide...

  12. 77 FR 4363 - Certain Dimmable Compact Fluorescent Lamps and Products Containing Same; Receipt of Complaint...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-27

    ... COMMISSION Certain Dimmable Compact Fluorescent Lamps and Products Containing Same; Receipt of Complaint... complaint entitled In Re Certain Dimmable Compact Fluorescent Lamps and Products Containing Same, DN 2873... within the United States after importation of certain dimmable compact fluorescent lamps and...

  13. 77 FR 11587 - Certain Dimmable Compact Fluorescent Lamps and Products Containing Same; Institution of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-27

    ... COMMISSION Certain Dimmable Compact Fluorescent Lamps and Products Containing Same; Institution of... States after importation of certain dimmable compact fluorescent lamps and products containing same by... certain dimmable compact fluorescent lamps and products containing same that infringe one or more of...

  14. Phototoxic maculopathy induced by quartz infrared heat lamp

    PubMed Central

    Zheng, Xinhua; Xie, Ping; Hu, Zizhong; Zhang, Weiwei; Liang, Kang; Wang, Xiuying; Liu, Qinghuai

    2017-01-01

    Abstract Rationale: A large proportion of the output of quartz infrared heat lamps is emitted as infrared radiation (IR). Retinal damage induced by IR-A and visible light on arc welders has been reported. However, case reports of retinal damage caused by quartz infrared heat lamps are rare. To the best of our knowledge, this is the first reported case of phototoxic maculopathy induced by quartz infrared heat lamps. Patient concerns: We report a female with a 1-month history of progressive blurred vision and dysmorphopsia in her right eye after improper staring at the tubes of a quartz infrared heater. Her best corrected visual acuity of the right eye was 20/32. Optical coherence tomography revealed a defect from the ellipsoid zone to retinal pigment epithelium (RPE)/Bruch's complex layer with a diameter of 360mmat its widest. P1 amplitudes in the two central concentric rings were reduced as assessed by multifocal electroretinography. Diagnoses: The patient was diagnosed with phototoxic maculopathy. Interventions: The patient was advised to cease all exposure to the infrared heater and was treated with peribulbar injections of methylprednisolone, oral Pancreatic Kininogenase, and oral Mecobalamin. Outcomes: Ten months later, her BCVA improved to 20/20. All examination results returned to normal except for a small residual defect in the interdigitation zone and RPE/Bruch's complex layer in her optical coherence tomography. Lessons: Light emitted by quartz infrared heat lamps may cause damage to the retina through photothermal and photochemical means. The public is insufficiently aware of the hazard potential of infrared heat lamps and other IR-A sources on human retina. PMID:28099337

  15. Excimer-laser-induced surface treatments on metal and ceramic materials: applications to automotive, aerospace, and microelectronic industries

    NASA Astrophysics Data System (ADS)

    Autric, Michel L.

    1999-09-01

    Surface treatments by laser irradiation can improve materials properties in terms of mechanical and physico- chemical behaviors, these improvements being related to the topography, the hardness, the microstructure, the chemical composition. Up to now, the use of excimer lasers for industrial applications remained marginal in spite of the interest related to the short wavelength (high photon energy and better energetic coupling with materials and reduced thermal effects in the bulk material). Up to now, the main limitations concerned the beam quality, the beam delivery, the gas handling and the relatively high investment cost. At this time, the cost of laser devices is going down and the ultraviolet radiation can be conducted through optical fibers. These two elements give new interest in using excimer laser for industrial applications. The main objective of this research program which we are involved in, is to underline some materials processing applications for automotive, aerospace or microelectronic industries for which it could be more interesting to use excimer lasers (minimized thermal effects). This paper concerns the modifications of the roughness, porosity, hardness, structure, phase, residual stresses, chemical composition of the surface of materials such as metallic alloys (aluminum, steel, cast iron, titanium, and ceramics (oxide, nitride, carbide,...) irradiated by KrF and XeCl excimer lasers.

  16. CALiPER Retail Lamps Study 3.2: Lumen and Chromaticity Maintenance of LED A Lamps Operated in Steady-State Conditions

    SciTech Connect

    none,

    2014-12-31

    This CALiPER report examines lumen depreciation and color shift of 17 different A lamps in steady-state conditions (15 LED, 1 CFL, 1 halogen). The goal of this investigation was to examine the long-term performance of complete LED lamps relative to benchmark halogen and CFL lamps—in this case, A lamps emitting approximately 800 lumens operated continuously at a relatively high ambient temperature of 45°C.

  17. Color Degradation of Textiles with Natural Dyes and of Blue Scale Standards Exposed to White LED Lamps:Evaluation of White LED Lamps for Effectiveness as Museum Lighting

    NASA Astrophysics Data System (ADS)

    Ishii, Mie; Moriyama, Takayoshi; Toda, Masahiro; Kohmoto, Kohtaro; Saito, Masako

    White light-emitting diodes (LED) are well suited for museum lighting because they emit neither UV nor IR radiation, which damage artifacts. The color degradation of natural dyes and blue scale standards (JIS L 0841) by white LED lamps are examined, and the performance of white LED lamps for museum lighting is evaluated. Blue scale standard grades 1-6 and silk fabrics dyed with 22 types of natural dyes classified as mid to highly responsive in a CIE technical report (CIE157:2004) were exposed to five types of white LED lamps using different luminescence methods and color temperatures. Color changes were measured at each 15000 lx·hr (500 lx at fabric surface × 300 hr) interval ten times. The accumulated exposure totaled 150000 lx·hr. The data on conventional white LED lamps and previously reported white fluorescent (W) and museum fluorescent (NU) lamps was evaluated. All the white LED lamps showed lower fading rates compared with a W lamp on a blue scale grade 1. The fading rate of natural dyes in total was the same between an NU lamp (3000 K) and a white LED lamp (2869 K). However, yellow natural dyes showed higher fading rates with the white LED lamp. This tendency is due to the high power characteristic of the LED lamp around 400-500 nm, which possibly contributes to the photo-fading action on the dyes. The most faded yellow dyes were Ukon (Curcuma longa L.) and Kihada (Phellodendron amurense Rupr.), and these are frequently used in historic artifacts such as kimono, wood-block prints, and scrolls. From a conservation point of view, we need to continue research on white LED lamps for use in museum lighting.

  18. Pore size effect on the dynamics of excimer formation for chemically attached pyrene on various silica surfaces

    SciTech Connect

    Dabestani, Reza T; Kidder, Michelle; Buchanan III, A C

    2008-01-01

    Excimer formation by pyrene is a well-known process in solution and on solid surfaces. In solution, excimer formation is highly dependent on the concentration of pyrene. When adsorbed on solid surfaces (i.e., silica surfaces), pyrene has been shown to form ground-state pairs which lead to static excimer emission even at very low surface coverages as a result of a solvent pooling effect induced during solvent removal from the surface. Ground-state pairing on silica surfaces results from a {pi}-{pi} interaction between two adjacent pyrene molecules and can not be avoided even by slow evaporation of the solvent from the surface as the molecules diffuse toward one another during the process. One possible method to alleviate the pairing of pyrene molecules and hence the formation of excimer is to chemically attach pyrene molecules to the silica surface. Chemical attachment, however, does not allow effective control over the spacing between the pyrene molecules to avoid ground-state pairing. To circumvent this, spacer molecules can be incorporated onto the surface by chemical attachment to control the spacing between two adjacent pyrene molecules. Furthermore, by using surfaces that provide various pore sizes, it is possible to control the number of pyrene molecules that can be grafted onto and confined to the pore surface, as well as the steric environment in which the molecules can rotate. Cabosil (fumed silica with no pores) and mesoporous silica surfaces with various pore diameters (i.e., MCM-41) are ideal candidates to examine the feasibility of controlling the spacing between pyrene molecules on a flat surface and confined inside the pores using a cografted spacer molecule (i.e., biphenyl). We have now used such an approach to examine the extent of excimer formation as the ratio of spacer/pyrene molecules is varied on nonporous silica surfaces as well as mesoporous silica surfaces with various pore diameters. Our results show that a decrease in the ratio of spacer

  19. Effect of an antioxydant cream versus placebo in patients with vitiligo in association with excimer laser. A pilot randomized, investigator-blinded, and half-side comparison trial.

    PubMed

    Leone, G; Paro Vidolin, A

    2015-08-01

    The aim of this study was to evaluate the combined effect of excimer laser and a topical antioxidant in the treatment for vitiligo. The study was conducted in a single blinded design on 10 vitiligo patients with symmetrical vitiligo lesions treated with the active antioxidant or a placebo that were irradiated with an excimer laser. Results have shown that the lesions treated with the active cream achieved earlier regimentation compared to the placebo. The use of a cream containing antioxidants may improve the results of excimer laser treatment in patients with vitiligo.

  20. LAMP5 Fine-Tunes GABAergic Synaptic Transmission in Defined Circuits of the Mouse Brain

    PubMed Central

    Tiveron, Marie-Catherine; Beurrier, Corinne; Céni, Claire; Andriambao, Naly; Combes, Alexis; Koehl, Muriel; Maurice, Nicolas; Gatti, Evelina; Abrous, Dhoher Nora; Kerkerian-Le Goff, Lydia; Pierre, Philippe; Cremer, Harold

    2016-01-01

    LAMP5 is member of the LAMP family of membrane proteins. In contrast to the canonical members of this protein family, LAMP1 and LAMP2, which show widespread expression in many tissues, LAMP 5 is brain specific in mice. In C. elegans, the LAMP5 ortholog UNC-46 has been suggested to act a trafficking chaperone, essential for the correct targeting of the nematode vesicular GABA-transporter UNC-47. We show here that in the mouse brain LAMP5 is expressed in subpopulations of GABAergic forebrain neurons in the striato-nigral system and the olfactory bulb. The protein was present at synaptic terminals, overlapping with the mammalian vesicular GABA-transporter VGAT. In LAMP5-deficient mice localization of the transporter was unaffected arguing against a conserved role in VGAT trafficking. Electrophysiological analyses in mutants showed alterations in short term synaptic plasticity suggesting that LAMP5 is involved in controlling the dynamics of evoked GABAergic transmission. At the behavioral level, LAMP5 mutant mice showed decreased anxiety and deficits in olfactory discrimination. Altogether, this work implicates LAMP5 function in GABAergic neurotransmission in defined neuronal subpopulations. PMID:27272053

  1. Particle Generation by Pulsed Excimer Laser Ablation in Liquid: Hollow Structures and Laser-Induced Reactions

    NASA Astrophysics Data System (ADS)

    Yan, Zijie

    2011-12-01

    Pulsed laser ablation of solid targets in liquid media is a powerful method to fabricate micro-/nanoparticles, which has attracted much interest in the past decade. It represents a combinatorial library of constituents and interactions, and one can explore disparate regions of parameter space with outcomes that are impossible to envision a priori. In this work, a pulsed excimer laser (wavelength 248 nm, pulse width 30 ns) has been used to ablate targets in liquid media with varying laser fluences, frequencies, ablation times and surfactants. It is observed that hollow particles could be fabricated by excimer laser ablation of Al, Pt, Zn, Mg, Ag, Si, TiO2, and Nb2O5 in water or aqueous solutions. The hollow particles, with sizes from tens of nanometers to micrometers, may have smooth and continuous shells or have morphologies demonstrating that they were assembled from nanoparticles. A new mechanism has been proposed to explain the formation of these novel particle geometries. They were formed on laser-produced bubbles through bubble interface pinning by laser-produced solid species. Considering the bubble dynamics, thermodynamic and kinetic requirements have been discussed in the mechanism that can explain some phenomena associated with the formation of hollow particles, especially (1) larger particles are more likely to be hollow particles; (2) Mg and Al targets have stronger tendency to generate hollow particles; and (3) the 248 nm excimer laser is more beneficial to fabricate hollow particles in water than other lasers with longer wavelengths. The work has also demonstrated the possiblities to fabricate novel nanostructures through laser-induced reactions. Zn(OH)2/dodecyl sulfate flower-like nanostructures, AgCl cubes, and Ag2O cubes, pyramids, triangular plates, pentagonal rods and bars have been obtained via reactions between laser-produced species with water, electrolyes, or surfactant molecules. The underlying mechanisms of forming these structures have been

  2. Excimer laser angioplasty in acute myocardial infarction (the CARMEL multicenter trial).

    PubMed

    Topaz, On; Ebersole, Douglas; Das, Tony; Alderman, Edwin L; Madyoon, Hooman; Vora, Kishor; Baker, John D; Hilton, David; Dahm, Johannes B

    2004-03-15

    Patients with acute myocardial infarction (AMI) with thrombus-laden lesions constitute a revascularization challenge. Thrombus and atherosclerotic plaque absorb laser energy; thus, we studied the safety and efficacy of excimer laser in AMI. In a multicenter trial, 151 patients with AMI underwent excimer laser angioplasty. Baseline left ventricular ejection fraction was 44 +/- 13%, and 13% of patients were in cardiogenic shock. A saphenous vein graft was the target vessel in 21%. Quantitative coronary angiography and statistical analysis were performed by independent core laboratories. A 95% device success, 97% angiographic success, and 91% overall procedural success rate were recorded. Maximal laser gain was achieved in lesions with extensive thrombus burden (p <0.03 vs small burden). Thrombolysis In Myocardial Infarction (TIMI) trial flow increased significantly by laser: 1.2 +/- 1.1 to 2.8 +/- 0.5 (p <0.001), reaching a final 3.0 +/- 0.2 (p <0.001 vs baseline). Minimal luminal diameter increased by laser from 0.5 +/- 0.5 to 1.6 +/- 0.5 mm (mean +/- SD, p <0.001), followed by 2.7 +/- 0.6 mm after stenting (p <0.001 vs baseline and vs after laser). Laser decreased target stenosis from 83 +/- 17% to 52 +/- 15% (mean +/- SD, p <0.001 vs baseline), followed by 20 +/- 16% after stenting (p <0.001 vs baseline and vs after laser). Six patients (4%) died, each presented with cardiogenic shock. Complications included perforation (0.6%), dissection (5% major, 3% minor), acute closure (0.6%), distal embolization (2%), and bleeding (3%). In a multivariant regression model, absence of cardiogenic shock was a significant factor affecting procedural success. Thus, in the setting of AMI, gaining maximal thrombus dissolution in lesions with extensive thrombus burden, combined with a considerable increase in minimal luminal diameter and restoration of anterograde TIMI flow, support successful debulking by excimer laser. The presence of thrombus does not adversely affect procedural

  3. MALARIA DIAGNOSIS BY LOOP-MEDIATED ISOTHERMAL AMPLIFICATION (LAMP) IN THAILAND.

    PubMed

    Ocker, Ronja; Prompunjai, Yongyut; Chutipongvivate, Salakchit; Karanis, Panagiotis

    2016-01-01

    The loop-mediated isothermal amplification method (LAMP) is a recently developed molecular technique that amplifies nucleic acid under isothermal conditions. For malaria diagnosis, 150 blood samples from consecutive febrile malaria patients, and healthy subjects were screened in Thailand. Each sample was diagnosed by LAMP, microscopy and nested polymerase chain reaction (nPCR), using nPCR as the gold standard. Malaria LAMP was performed using Plasmodiumgenus and Plasmodium falciparum specific assays in parallel. For the genus Plasmodium, microscopy showed a sensitivity and specificity of 100%, while LAMP presented 99% of sensitivity and 93% of specificity. For P. falciparum, microscopy had a sensitivity of 95%, and LAMP of 90%, regarding the specificity; and microscopy presented 93% and LAMP 97% of specificity. The results of the genus-specific LAMP technique were highly consistent with those of nPCR and the sensitivity of P. falciparum detection was only marginally lower.

  4. Excimer Lasers

    DTIC Science & Technology

    1976-06-01

    CONTINUE 46 C HATE CONSTANTS - ELCTRONIC VD=SQRT(2*TE/MASXE)* 3E10 J=NE*E*VD VDISC=V-H*J*A-L*A*E*VD*(NE-NEP)/DT NEP=NE RC=6.38E7*(5QRT(2*TE))**3...TG)/ 3E10 +CSTMDE*P**2*EXP(-VüXE/ +TG)*.25/3EI0 BETAD=CSTMD*P**2*EXP(-VDX/TG)*.25/ 3E10 GAJNE=CSTME*(PX1*EXP(-VEA/TG)/(KAEX*1.5)-2*P*XE*EXP(-VEX/TG...3EI0 +-CSTMDE*(P**2*EXP(-VDXE/TG)*.25)/ 3E10 GAIND=CSTMD*(PD1*EXP(-VDA/TG)/(KADI*12)-P**2*EXP(-VDX/TG)*.25) +/3EI0 C OUTPUT IF(ISTEP/IPrMNT-FL()AT

  5. Unwanted reflections during slit lamp assisted binocular indirect ophthalmoscopy

    NASA Astrophysics Data System (ADS)

    Sheehan, Matthew; Goncharov, Alexander

    2011-11-01

    Binocular indirect ophthalmoscopy is a routine ophthalmic examination procedure. Two different apparatus setups are commonly employed; the head/spectacle mounted designs of Schepens and slit lamp assisted ophthalmoscopy, both typically performed through a fundus lens of high positive power. It can be difficult for clinicians to avoid unwanted back reflections primarily emanating from the fundus lens and the pre-corneal tear film, particularly when initially learning the skills required to perform the examination. In this investigation the illumination system of a slit lamp was modified to include a variety of obscuration designs optically conjugate to surfaces responsible for creating unwanted reflections. The modified apparatus was then used to perform binocular indirect ophthalmoscopy on an artificial eye and on real eyes. Clinicians used questionnaires to score the appearance of reflections. The mean scores were similar across all trials, including the control unmodified trial, indicating general consensus that the modified illumination system provided no substantial effect on the perception of these unwanted reflections.

  6. LED lamp incorporating remote phosphor with heat dissipation features

    DOEpatents

    Tong, Tao; Letoquin, Ronan; Keller, Bernd; Tarsa, Eric

    2016-11-22

    An LED lamp or bulb is disclosed that comprises a light source, a heat sink structure and a remote planar phosphor carrier having at least one conversion material. The phosphor carrier can be remote to the light sources and mounted to the heat sink so that heat from the phosphor carrier spreads into the heat sink. The phosphor carrier can comprise a thermally conductive transparent material and a phosphor layer, with an LED based light source mounted to the heat sink such that light from the light source passes through the phosphor carrier. At least some of the LED light is converted by the phosphor carrier, with some lamp embodiments emitting a white light combination of LED and phosphor light. The phosphor arranged according to the present invention can operate at lower temperature to thereby operate at greater phosphor conversion efficiency and with reduced heat related damage to the phosphor.

  7. Mercury speciation in fluorescent lamps by thermal release analysis

    SciTech Connect

    Raposo, Claudio; Windmoeller, Claudia Carvalhinho; Durao Junior, Walter Alves

    2003-07-01

    In this work, mercury speciation in phosphorus powder matrices and soda lime glass waste from new and spent fluorescent lamp wastes has been studied by thermo-desorption/atomic absorption spectrometry (TDAAS), X-ray diffraction (XRD), cold vapor-atomic absorption (CV-AAS) and atomic emission spectrometry/inductively coupled plasma (ICP/AES). TDAAS results show the presence of oxidized forms of mercury, i.e., Hg{sup 1+} and Hg{sup 2+}, especially in wastes with high mercury concentration. Such forms are mobile, and therefore represent a potential hazard waste material. Glass TD profiles of spent fluorescent lamps suggested the presence of mercury strongly linked to the matrix, which desorbs only at high temperatures.

  8. Mercury speciation in fluorescent lamps by thermal release analysis.

    PubMed

    Raposo, Cláudio; Windmöller, Cláudia Carvalhinho; Durão, Walter Alves

    2003-01-01

    In this work, mercury speciation in phosphorus powder matrices and soda lime glass waste from new and spent fluorescent lamp wastes has been studied by thermo-desorption/atomic absorption spectrometry (TDAAS), X-ray diffraction (XRD), cold vapor-atomic absorption (CV-AAS) and atomic emission spectrometry/inductively coupled plasma (ICP/AES). TDAAS results show the presence of oxidized forms of mercury, i.e., Hg(1+) and Hg(2+), especially in wastes with high mercury concentration. Such forms are mobile, and therefore represent a potential hazard waste material. Glass TD profiles of spent fluorescent lamps suggested the presence of mercury strongly linked to the matrix, which desorbs only at high temperatures.

  9. ACS/SBC Internal Lamp P-flat Monitoring

    NASA Astrophysics Data System (ADS)

    Avila, Roberto J.; Chiaberge, Marco; Bohlin, Ralph

    2016-06-01

    We report on a Cycle 23 calibration program to monitor the status of the SBC P-flat. We find random pixel to pixel changes to be small, with only ˜2% of pixels having changed by more than 3σ. There are coherent changes that we measure to be above the poisson errors, in some regions as high as 4% peak to peak. We therefore recommend that the ACS team obtain new observations in order to create a new P-flat. We also measured the degradation of the deuterium lamp used to create internal flats. The brightness of the lamp is currently ˜65% of its initial level, the degradation being dependent on lifetime usage.

  10. Sonolysis of an oxalic acid solution under xenon lamp irradiation.

    PubMed

    Tanaka, Hisashi; Harada, Hisashi

    2010-06-01

    The photosonolysis of oxalic acid was carried out in an Ar atmosphere. The detectable products of sonolysis were CO(2), CO, H(2), and H(2)O(2). The yield of CO(2) was higher than that for the sum of sonolysis and photolysis reactions. Namely, a synergistic effect was observed during simultaneous irradiations of 200 kHz ultrasound and Xe lamp. The degradation of oxalic acid was promoted by active species such as H(2)O(2) produced from water by sonolysis. An oxalic acid-H(2)O(2) complex is likely to be present in the solution, but could not be detected. The effects of not only the photo-irradiation but also the thermal or incident energy during Xe lamp illumination were also considered.

  11. LAMP2A as a therapeutic target in Parkinson disease.

    PubMed

    Xilouri, Maria; Brekk, Oeystein Roed; Kirik, Deniz; Stefanis, Leonidas

    2013-12-01

    Abnormal aggregation of SNCA/?-synuclein plays a crucial role in Parkinson disease (PD) pathogenesis. SNCA levels determine its toxicity, and its accumulation, even to a small extent, may be a risk factor for neurodegeneration. One of the main pathways for SNCA degradation is chaperone-mediated autophagy (CMA), a selective form of autophagy, while aberrant SNCA may act as a CMA inhibitor. In the current punctum we summarize our recent data showing that induction of CMA, via overexpression of the protein controlling its rate-limiting step, the lysosomal receptor LAMP2A, effectively decreases SNCA levels and ameliorates SNCA-induced neurodegeneration, both in neuronal cell culture systems and in the rat brain. Such findings suggest that modulation of LAMP2A and, consequently, CMA, represents a viable therapeutic target for PD and other synucleinopathies where SNCA accumulation and aggregation plays a fundamental role.

  12. Metal halide arc discharge lamp having short arc length

    NASA Technical Reports Server (NTRS)

    Muzeroll, Martin E. (Inventor)

    1994-01-01

    A metal halide arc discharge lamp includes a sealed light-transmissive outer jacket, a light-transmissive shroud located within the outer jacket and an arc tube assembly located within the shroud. The arc tube assembly includes an arc tube, electrodes mounted within the arc tube and a fill material for supporting an arc discharge. The electrodes have a spacing such that an electric field in a range of about 60 to 95 volts per centimeter is established between the electrodes. The diameter of the arc tube and the spacing of the electrodes are selected to provide an arc having an arc diameter to arc length ratio in a range of about 1.6 to 1.8. The fill material includes mercury, sodium iodide, scandium tri-iodide and a rare gas, and may include lithium iodide. The lamp exhibits a high color rendering index, high lumen output and high color temperature.

  13. Micromachining of polyurethane (PU) polymer using a KrF excimer laser (248 nm)

    NASA Astrophysics Data System (ADS)

    Singh, Sarabpreet; Sharma, Sunil

    2014-12-01

    Polyurethane (PU) polymer, due to its biocompatibility, weather resistance, and favorable physical properties, finds a number of applications in medical implants, protective coatings, and as a prototype material for structural components in MEMS devices. An excimer laser (wavelength = 248 nm, FWHM = 25 ns) is employed for micromachining of polyurethane (PU) polymer. For air environment, the ablation rate is 0.18 μm/pulse and for underwater environment, the ablation rate is 0.07 μm/pulse (with underwater ablation threshold as 0.10 J/cm2), which concluded low taper angles (∼32°) for in air as compared to high taper angles (∼65°) with underwater micromachining. The experimental results for air and under water micromachining demonstrate ablation process as a combination of photo-thermal and photo-chemical mechanism.

  14. About Losses in Pumping Generators of High-Power Electrodischarge Excimer Lasers

    NASA Astrophysics Data System (ADS)

    Ivanov, N. G.; Losev, V. F.

    2015-04-01

    Energy losses in pumping systems of discharge high-power lasers are investigated. To estimate the losses, the discharge circuit operation was modeled, and its calculation was performed using the program PSpice. Results of measurements and calculations demonstrate that the resistance of a rail gap with electric field distortion exceeds several times the resistance of a single-channel gap without field distortion. A difference in the resistances is explained by different mechanisms of discharge burning: in the first case diffusion mechanism and in the second case the spark mechanism. The low efficiency of the high-power excimer lasers (~1%) is explained by high energy losses in the rail gap that reach more than 50% of the initially stored energy.

  15. Positive ion emission from oxidized aluminum during ultraviolet excimer laser irradiation

    SciTech Connect

    Khan, Enamul; Langford, S. C.; Dickinson, J. T.

    2011-07-15

    We report quadrupole mass-selected time-of-flight measurements of positive ions from oxidized aluminum metal (and for comparison, single-crystal sapphire) during pulsed excimer laser irradiation at 193 and 248 nm. This work focuses on laser fluences well below onset of rapid etching or optical breakdown. By far the most intense emissions are due to Al{sup +}. On previously unexposed material, the ion kinetic energies are initially well above the photon energy, consistent with the ejection of Al{sup +} sorbed at surface electron traps. During prolonged irradiation, the emission intensities and kinetic energies gradually fall. Emission from patches of oxide would account for previous reports of laser-induced Al{sup +} emission from metallic aluminum surfaces cleaned by ion etching if patches of thin oxide were to survive the etching treatment.

  16. Modulation of corneal wound healing after excimer laser keratomileusis using topical mitomycin C and steroids

    SciTech Connect

    Talamo, J.H.; Gollamudi, S.; Green, W.R.; De La Cruz, Z.; Filatov, V.; Stark, W.J. )

    1991-08-01

    A 193-nm excimer laser system was used to create deep stromal ablations in seven New Zealand white rabbits and shallow ablations in three. Eyes were randomized for treatment with topical mitomycin C, steroids, and erythromycin; topical steroids and erythromycin; or topical erythromycin only. All treatment regimens were instituted twice daily for 14 days. All eyes reepithelialized normally within 3 to 5 days. During 10 weeks of follow-up, all eyes developed moderate reticular subepithelial haze without significant differences among treatment groups. Results of light, fluorescence, and electron microscopic examination showed anterior stromal scarring and markedly reduced new subepithelial collagen formation in the group treated with mitomycin C, corticosteroids, and erythromycin. Focal abnormalities of Descemet's membrane and endothelial abnormalities were present in all treatment groups. Combination therapy with topical steroids, mitomycin C, and erythromycin to control the corneal wound healing response after refractive laser surgery appears promising and warrants further study.

  17. Surface modification of dental tissues by KrF excimer laser radiation

    NASA Astrophysics Data System (ADS)

    Sivakumar, M.; Oliveira, V.; Vilar, R.

    2007-02-01

    Laser treatment is a promising technique for dental applications such as caries removal, dental hypersensitivity reduction and improvement of the bond strength between dentin and restoration materials. In this study the topographic and morphological changes induced in enamel and dentin surfaces by treating with KrF excimer laser radiation were studied as a function of the number of laser pulses and radiation fluence by scanning electron microscopy and optical profilometry. For enamel, independently of the fluence used, material removal occurs preferentially at the prisms sheaths, leading to the formation of surface pits of a few micrometers. For dentin, a cone-like topography develops when the tubules are approximately parallel to the laser beam direction and the radiation fluence is within the range 0.5 to 1.5 J/cm2. For higher fluences, the treated surfaces are flat and covered with a layer of re-solidified materials.

  18. AlGaAs growth by OMCVD using an excimer laser

    NASA Technical Reports Server (NTRS)

    Warner, Joseph D.; Wilt, David M.; Pouch, John J.; Aron, Paul R.

    1986-01-01

    AlGaAs has been grown on GaAs by laser assisted OMCVD using an excimer laser, wavelength 193 nm, and a Cambridge OMCVD reactor. Films were grown at temperatures of 450 and 500 C with the laser beam parallel to the surface and impinging onto the surface at 15 deg from parallel. The samples were heated by RF coils while the laser beam was perpendicular to the gas flow. Typical gas flow parameters are 12 slm of H2, 15 sccm of Ga(CH3)3, 13 sccm of Al(CH3)3, and a pressure of 250 mbar. The initial energy density of the beam at the surface was 40 mJ/sq cm, the pulse rate was 20 pps, and the growth time was 7 min. The films were analyzed by Auger electron spectroscopy for the aluminum concentration and by TEM for the surface morphology.

  19. [The effect of tranilast on subepithelial corneal opacity after excimer laser keratectomy].

    PubMed

    Sakai, T; Okamoto, S; Iwaki, Y

    1997-10-01

    Recent studies have reported that tranilast inhibited in vitro the proliferation of keratocytes from corneal subepithelial opacities (haze) and collagen synthesis in cultured corneas after excimer laser photorefractive keratectomy (PRK). In this study 0.5% tranilast eye drops, 0.1% betametazone phosphate eyedrops, and a 0.5% tranilast base solution (control) were administered four times daily to rabbits which had undergone PRK. Weekly evaluation of the inhibitory effect of these drugs on haze began two weeks after surgery according to Fantes' classification. 0.5% tranilast suppressed haze from six weeks to thirteen weeks after PRK (p < 0.05). 0.1% betametazone phosphate showed no effect. These results suggested that 0.5% tranilast had a satisfactory therapeutic effect on haze after PRK.

  20. 193 nm Excimer laser processing of Si/Ge/Si(100) micropatterns

    NASA Astrophysics Data System (ADS)

    Gontad, F.; Conde, J. C.; Chiussi, S.; Serra, C.; González, P.

    2016-01-01

    193 nm Excimer laser assisted growth and crystallization of amorphous Si/Ge bilayer patterns with circular structures of 3 μm diameter and around 25 nm total thickness, is presented. Amorphous patterns were grown by Laser induced Chemical Vapor Deposition, using nanostencils as shadow masks and then irradiated with the same laser to induce structural and compositional modifications for producing crystalline SiGe alloys through fast melting/solidification cycles. Compositional and structural analyses demonstrated that pulses of 240 mJ/cm2 lead to graded SiGe alloys with Si rich discs of 2 μm diameter on top, a buried Ge layer, and Ge rich SiGe rings surrounding each feature, as predicted by previous numerical simulation.