ERIC Educational Resources Information Center
North Central Technical Inst., Wausau, WI.
This final report contains the program proposal with supporting data for developing curriculum materials for and implementing an associate-degree laser technology program at the North Central Technical Institute. The proposal outline provides this information: (1) objectives for the program designed to prepare a technician to safely operate,…
NEET-AMM Final Technical Report on Laser Direct Manufacturing (LDM) for Nuclear Power Components
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, Scott; Baca, Georgina; O'Connor, Michael
2015-12-31
Final technical report summarizes the program progress and technical accomplishments of the Laser Direct Manufacturing (LDM) for Nuclear Power Components project. A series of experiments varying build process parameters (scan speed and laser power) were conducted at the outset to establish the optimal build conditions for each of the alloys. Fabrication was completed in collaboration with Quad City Manufacturing Laboratory (QCML). The density of all sample specimens was measured and compared to literature values. Optimal build process conditions giving fabricated part densities close to literature values were chosen for making mechanical test coupons. Test coupons whose principal axis is onmore » the x-y plane (perpendicular to build direction) and on the z plane (parallel to build direction) were built and tested as part of the experimental build matrix to understand the impact of the anisotropic nature of the process.. Investigations are described 316L SS, Inconel 600, 718 and 800 and oxide dispersion strengthed 316L SS (Yttria) alloys.« less
NASA Astrophysics Data System (ADS)
Barty, C. P. J.; Key, M.; Britten, J.; Beach, R.; Beer, G.; Brown, C.; Bryan, S.; Caird, J.; Carlson, T.; Crane, J.; Dawson, J.; Erlandson, A. C.; Fittinghoff, D.; Hermann, M.; Hoaglan, C.; Iyer, A.; Jones, L., II; Jovanovic, I.; Komashko, A.; Landen, O.; Liao, Z.; Molander, W.; Mitchell, S.; Moses, E.; Nielsen, N.; Nguyen, H.-H.; Nissen, J.; Payne, S.; Pennington, D.; Risinger, L.; Rushford, M.; Skulina, K.; Spaeth, M.; Stuart, B.; Tietbohl, G.; Wattellier, B.
2004-12-01
The technical challenges and motivations for high-energy, short-pulse generation with NIF and possibly other large-scale Nd : glass lasers are reviewed. High-energy short-pulse generation (multi-kilojoule, picosecond pulses) will be possible via the adaptation of chirped pulse amplification laser techniques on NIF. Development of metre-scale, high-efficiency, high-damage-threshold final optics is a key technical challenge. In addition, deployment of high energy petawatt (HEPW) pulses on NIF is constrained by existing laser infrastructure and requires new, compact compressor designs and short-pulse, fibre-based, seed-laser systems. The key motivations for HEPW pulses on NIF is briefly outlined and includes high-energy, x-ray radiography, proton beam radiography, proton isochoric heating and tests of the fast ignitor concept for inertial confinement fusion.
ERIC Educational Resources Information Center
Luzerne County Community Coll., Nanticoke, PA.
A project was conducted at the Community College of Luzerne County (Pennsylvania) to develop, in cooperation with area vocational-technical schools, the first year of a competency-based curriculum in laser/electro-optics technology. Existing programs were reviewed and private sector input was sought in developing the curriculum and identifying…
Development of a Curriculum in Laser Technology. Final Report.
ERIC Educational Resources Information Center
Wasserman, William J.
A Seattle Central Community College project visited existing programs, surveyed need, and developed a curriculum for a future program in Laser-Electro-Optics (LEO) Technology. To establish contacts and view successful programs, project staff made visits to LEO technology programs at San Jose City College and Texas State Technical Institute, Center…
A Dissemination Model for New Technical Education Programs. Final Report.
ERIC Educational Resources Information Center
Hull, Daniel M.
The Technical Education Research Center-SW has conceived, tested, and refined a model for disseminating newly developed programs and materials throughout the nation. The model performed successfully in the dissemination of more than 50,000 educational units (modules) of Laser/Electro-Optics Technician (LEOT) materials during a four-year period…
ERIC Educational Resources Information Center
Luzerne County Community Coll., Nanticoke, PA.
The project described in this report was conducted at the Community College of Luzerne County (Pennsylvania) to develop, in conjunction with area vocational-technical schools, the second year of a competency-based curriculum in laser/electro-optics technology. During the project, a task force of teachers from the area schools and the college…
Final Technical Report of Project DE-FG02-96ER14647
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lundeen, Stephen R.
This is the final technical report of work completed under DOE support over the period Sept. 1, 1996 until May 31, 2015. The title of the project was "Ion/Excited Atom Collision Studies with a Rydberg Target and a CO2 Laser" from 9/1/96 to 10/31/06, and "Properties of Actinide Ions from Measurements of Rydberg Ion Fine Structure" from 11/1/06 until 5/31/15. The primary technical results were a detailed experimental study of resonant charge transfer between Rydberg atoms and highly-charged ions, and unique measurements of many properties of multiply-charged Thorium ions.
NASA Technical Reports Server (NTRS)
Davis, M. H.
1981-01-01
Final development of a gravimetric test for performance evaluation of a precision saturator is described. The design and development of a prototype droplet levitation chamber is discussed. Technical assistance to the MSFC Airborne Laser Doppler Program is reported.
NASA Astrophysics Data System (ADS)
Gu, Chunxing; Shen, Zongbao; Liu, Huixia; Li, Pin; Lu, Mengmeng; Zhao, Yinxin; Wang, Xiao
2013-04-01
This paper describes a precise and non-contact adjustment technique using the water-confined laser-generated plasma to adjust the curvature of micro-components (micro-mechanical cantilevers). A series of laser shock micro-adjustment experiments were conducted on 0.4 mm-thick Al samples using pulsed Nd:YAG lasers operating at 1064 nm wavelengths to verify the technical feasibility. Systematic study was carried out in the term of effects of various factors on the adjusting results, including laser energies, laser focus positions, laser shock times and confined regime configuration. The research results have shown that the different bending angles and bending directions can be obtained by changing the laser processing parameters. And, for the adjustment process, the absence of confined regime configuration could also generate suitable bending deformation. But, in the case of larger energy, the final surfaces would have the sign of ablation, hence resulting in poor surface quality. An analysis procedure including dynamic analysis performed by ANSYS/LS-DYNA and static analysis performed by ANSYS is presented in detail to attain the simulation of laser shock micro-adjustment to predict the final bending deformation. The predicted bending profiles is well correlated with the available experimental data, showing the finite element analysis can predict the final curvatures of the micro-cantilevers properly.
Performance calculation and simulation system of high energy laser weapon
NASA Astrophysics Data System (ADS)
Wang, Pei; Liu, Min; Su, Yu; Zhang, Ke
2014-12-01
High energy laser weapons are ready for some of today's most challenging military applications. Based on the analysis of the main tactical/technical index and combating process of high energy laser weapon, a performance calculation and simulation system of high energy laser weapon was established. Firstly, the index decomposition and workflow of high energy laser weapon was proposed. The entire system was composed of six parts, including classical target, platform of laser weapon, detect sensor, tracking and pointing control, laser atmosphere propagation and damage assessment module. Then, the index calculation modules were designed. Finally, anti-missile interception simulation was performed. The system can provide reference and basis for the analysis and evaluation of high energy laser weapon efficiency.
Self-optimizing approach for automated laser resonator alignment
NASA Astrophysics Data System (ADS)
Brecher, C.; Schmitt, R.; Loosen, P.; Guerrero, V.; Pyschny, N.; Pavim, A.; Gatej, A.
2012-02-01
Nowadays, the assembly of laser systems is dominated by manual operations, involving elaborate alignment by means of adjustable mountings. From a competition perspective, the most challenging problem in laser source manufacturing is price pressure, a result of cost competition exerted mainly from Asia. From an economical point of view, an automated assembly of laser systems defines a better approach to produce more reliable units at lower cost. However, the step from today's manual solutions towards an automated assembly requires parallel developments regarding product design, automation equipment and assembly processes. This paper introduces briefly the idea of self-optimizing technical systems as a new approach towards highly flexible automation. Technically, the work focuses on the precision assembly of laser resonators, which is one of the final and most crucial assembly steps in terms of beam quality and laser power. The paper presents a new design approach for miniaturized laser systems and new automation concepts for a robot-based precision assembly, as well as passive and active alignment methods, which are based on a self-optimizing approach. Very promising results have already been achieved, considerably reducing the duration and complexity of the laser resonator assembly. These results as well as future development perspectives are discussed.
Power-Scalable Blue-Green Bessel Beams
2016-02-23
19b. TELEPHONE NUMBER (Include area code) 02/23/2016 Final Technical JAN 2011 - DEC 2013 Power-Scalable Blue -Green Bessel Beams Siddharth Ramachandran...fiber lasers, non-traditional emission wavelengths, high-power blue -green tunabel lasers U U U SAR 11 Siddharth Ramachandran 617-353-9811 1 Power...Scalable Blue -Green Bessel Beams Siddharth Ramachandran Photonics Center, Boston University, 8 Saint Mary’s Street, Boston, MA 02215 phone: (617) 353
NASA Astrophysics Data System (ADS)
Maguen, Ezra I.; Salz, James J.; Papaioannou, Thanassis; Nesburn, Anthony B.
1995-05-01
Some technical factors relating to the use of the VISX model 20/20 excimer laser for photorefractive keratectomy will be discussed and the way they affect the final optical correction will be demonstrated, as follows: (1) Discontinuation of nitrogen flow: improved corneal haze but induced a mean undercorrection of 0.8 D, 18 months postoperatively. (2) Discontinuation of the use of the fixation ring did not affect centration in a statistically significant fashion. (3) Enlargement of the optical from 5.0 mm to 6.0 mm zone did not affect the refractive outcome. Visual acuity was improved in eyes which had PRK done with a 6.0 mm optical zone.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bohn, Willy L.
First, an introductory overview of the different types of laser propulsion techniques will be given and illustrated by some historical examples. Second, laser devices available for basic experiments will be reviewed ranging from low power lasers sources to inertial confinement laser facilities. Subsequently, a status of work will show the impasse in which the laser propulsion community is currently engaged. Revisiting the basic relations leads to new avenues in ablative and direct laser propulsion for ground based and space based applications. Hereby, special attention will be devoted to the impact of emerging ultra-short pulse lasers on the coupling coefficient andmore » specific impulse. In particular, laser sources and laser propulsion techniques will be tested in microgravity environment. A novel approach to debris removal will be discussed with respect to the Satellite Laser Ranging (SRL) facilities. Finally, some non technical issues will be raised aimed at the future prospects of laser propulsion in the international community.« less
Bio-Inspired Functional Surfaces Based on Laser-Induced Periodic Surface Structures
Müller, Frank A.; Kunz, Clemens; Gräf, Stephan
2016-01-01
Nature developed numerous solutions to solve various technical problems related to material surfaces by combining the physico-chemical properties of a material with periodically aligned micro/nanostructures in a sophisticated manner. The utilization of ultra-short pulsed lasers allows mimicking numerous of these features by generating laser-induced periodic surface structures (LIPSS). In this review paper, we describe the physical background of LIPSS generation as well as the physical principles of surface related phenomena like wettability, reflectivity, and friction. Then we introduce several biological examples including e.g., lotus leafs, springtails, dessert beetles, moth eyes, butterfly wings, weevils, sharks, pangolins, and snakes to illustrate how nature solves technical problems, and we give a comprehensive overview of recent achievements related to the utilization of LIPSS to generate superhydrophobic, anti-reflective, colored, and drag resistant surfaces. Finally, we conclude with some future developments and perspectives related to forthcoming applications of LIPSS-based surfaces. PMID:28773596
Bio-Inspired Functional Surfaces Based on Laser-Induced Periodic Surface Structures.
Müller, Frank A; Kunz, Clemens; Gräf, Stephan
2016-06-15
Nature developed numerous solutions to solve various technical problems related to material surfaces by combining the physico-chemical properties of a material with periodically aligned micro/nanostructures in a sophisticated manner. The utilization of ultra-short pulsed lasers allows mimicking numerous of these features by generating laser-induced periodic surface structures (LIPSS). In this review paper, we describe the physical background of LIPSS generation as well as the physical principles of surface related phenomena like wettability, reflectivity, and friction. Then we introduce several biological examples including e.g., lotus leafs, springtails, dessert beetles, moth eyes, butterfly wings, weevils, sharks, pangolins, and snakes to illustrate how nature solves technical problems, and we give a comprehensive overview of recent achievements related to the utilization of LIPSS to generate superhydrophobic, anti-reflective, colored, and drag resistant surfaces. Finally, we conclude with some future developments and perspectives related to forthcoming applications of LIPSS-based surfaces.
Fiber Based Optical Amplifier for High Energy Laser Pulses Final Report CRADA No. TC02100.0
DOE Office of Scientific and Technical Information (OSTI.GOV)
Messerly, M.; Cunningham, P.
This was a collaborative effort between Lawrence Livermore National Security, LLC (formerly The Regents of the University of California)/Lawrence Livermore National Laboratory (LLNL), and The Boeing Company to develop an optical fiber-based laser amplifier capable of producing and sustaining very high-energy, nanosecond-scale optical pulses. The overall technical objective of this CRADA was to research, design, and develop an optical fiber-based amplifier that would meet specific metrics.
1975-05-01
Finally, diagnostics for quantitative measurements of all these properties are necessary for meaningful comparison of the experiments with theoretical ...width (FWHM) of 120 ^rad. For comparison, a beam which fills the last amplifier rod has a corresponding theoretical divergence angle of 108 urad...hydrogen the protons produced by photoionization do not absorb). Also shown are the spontaneous lifetimes tu of the upper laser level, of use for self
Final Technical Report: Magnetic Reconnection in High-Energy Laser-Produced Plasmas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Germaschewski, Kai; Fox, William; Bhattacharjee, Amitava
This report describes the final results from the DOE Grant DE-SC0007168, “Fast Magnetic Reconnection in HED Laser-Produced Plasmas.” The recent generation of laboratory high-energy-density physics facilities has opened significant physics opportunities for experimentally modeling astrophysical plasmas. The goal of this proposal is to use these new tools to study fundamental problems in plasma physics and plasma astrophysics. Fundamental topics in this area involve study of the generation, amplification, and fate of magnetic fields, which are observed to pervade the plasma universe and govern its evolution. This project combined experiments at DOE laser facilities with kinetic plasma simulation to study thesemore » processes. The primary original goal of the project was to study magnetic reconnection using a new experimental platform, colliding magnetized laser-produced plasmas. However through a series of fortuitous discoveries, the work broadened out to allow significant advancement on multiple topics in laboratory astrophysics, including magnetic reconnection, Weibel instability, and collisionless shocks.« less
Managing the replacement cycle of laser inventory.
Davis, C E
1992-01-01
Medical lasers are quickly moving into the replacement phase of technology management. Barnes Hospital (St. Louis, MO) is using its laser team to define a process of planned laser replacement using the experience gained from traditional medical equipment replacement cycles, quality improvement principles and tools, and other formalized interdisciplinary teams. The process described in this paper has six basic steps: (1) A decision is made to request a replacement laser. (2) An appropriation request form is completed and submitted with the clinical and/or technical justifications. (3) Those requests initiated outside of the Clinical Engineering Department are reviewed by the Clinical Engineer/Medical Laser Safety Officer (CE/MLSO). (4) The CE/MLSO presents the requests to the hospital Laser Committee, and (5) then to the Laser Users' Group. (6) Finally, an Expenditure Authorization Committee reviews all capital expense requests, including those for replacement lasers, and allocates funds for the next fiscal year. This paper illustrates and evaluates the process, using an example from the review process for 1993 equipment purchases at Barnes Hospital.
Demonstration of Laser Plasma X-Ray Source with X-Ray Collimator Final Report CRADA No. TC-1564-99
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lane, S. M.; Forber, R. A.
2017-09-28
This collaborative effort between the University of California, Lawrence Livermore National Laboratory (LLNL) and JMAR Research, Inc. (JRI), was to demonstrate that LLNL x-ray collimators can effectively increase the wafer throughput of JRI's laser based x-ray lithography systems. The technical objectives were expected to be achieved by completion of the following tasks, which are separated into two task lists by funding source. The organization (LLNL or JMAR) having primary responsibility is given parenthetically for each task.
NASA Astrophysics Data System (ADS)
Batishche, Sergei; Englezis, Apostolis; Gorovets, Tatiana; Kouzmouk, Andrei; Pilipenka, Uladzimir; Pouli, Paraskevi; Tatur, Hennady; Totou, Garyfallia; Ukhau, Viktar
2005-07-01
In the present study, a newly developed one-beam IR-UV laser cleaning system is presented. This system may be used for different applications in diverse fields, such as outdoors stonework conservation and canvas paintings restoration. The simultaneous use of the fundamental radiation of a Q-switched Nd:YAG laser at 1064 nm and its third harmonic at 355 nm was found appropriate to clean pollution crusts, while ensuring that no discoloration ("yellowing") would occur. The optimum ratio of UV to IR wavelengths in the final cleaning beam was investigated. In parallel, the same system was tested in diverse applications, such as the removal of bonding glues from duplicated canvases. The optimum laser parameters were investigated both on technical samples as well as on original paintings.
Final Technical Report "Study of Efficiency of Raman Backscattering Amplification in Plasma"
DOE Office of Scientific and Technical Information (OSTI.GOV)
Suckewer, Szymon
2014-03-31
General : Our major scientific achievements in Raman Backscattering (RBS) amplification and compression of short laser pulses in plasma. The laser system based on RBS steps in where the current technology of chirped pulse amplification (CPA) (extremely successful in developing ultra-short and ultra-intense laser pulses in last 2 decades) becomes difficult and very expensive to apply. Good base for such RBS laser was created by our recent experiments, which were supported by GPS grants. The main objective of the present grant was: improvement efficiency of energy transfer from pump to seed. The results surpassed our expectations; we improved the efficiencymore » of energy transfer from pump to seed by a factor of 6 compared to the best of our previous results and amplified seed pulse compressed down to about 50 fsec.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, K.K.
A Mather-type dense plasma focus (MDPF) system was designed, built, and tested specifically to study its luminescent characteristics and to assess its potential as a new light source of high-energy, short-wavelength lasers. The luminescence study of MDPF showed that the conversion efficiency from the electrical input to the optical output energies is at least 50%, up to the time the plasma compression is complete. Using the system, for the first time as an optical pump, laser activities were successfully obtained from a variety of liquid organic dyes. Diagnostic capabilities included an optical multichannel analyzer system complete with a computer control,more » a nitrogen-pumped tunable dye-laser system, a high-speed streak/framing camera, a digital laser energy meter, voltage and current probes, and a computer-based data-acquisition system.« less
Status of the Advanced Virgo gravitational wave detector
NASA Astrophysics Data System (ADS)
Acernese, F.; Adams, T.; Agatsuma, K.; Aiello, L.; Allocca, A.; Amato, A.; Antier, S.; Arnaud, N.; Ascenzi, S.; Astone, P.; Bacon, P.; Bader, M. K. M.; Baldaccini, F.; Ballardin, G.; Barone, F.; Barsuglia, M.; Barta, D.; Basti, A.; Bawaj, M.; Bazzan, M.; Bejger, M.; Belahcene, I.; Bersanetti, D.; Bertolini, A.; Bitossi, M.; Bizouard, M. A.; Bloemen, S.; Boer, M.; Bogaert, G.; Bondu, F.; Bonnand, R.; Boom, B. A.; Boschi, V.; Bouffanais, Y.; Bozzi, A.; Bradaschia, C.; Branchesi, M.; Briant, T.; Brillet, A.; Brisson, V.; Bulik, T.; Bulten, H. J.; Buskulic, D.; Buy, C.; Cagnoli, G.; Calloni, E.; Canepa, M.; Canizares, P.; Capocasa, E.; Carbognani, F.; Casanueva Diaz, J.; Casentini, C.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cerboni Baiardi, L.; Cerretani, G.; Cesarini, E.; Chassande-Mottin, E.; Chincarini, A.; Chiummo, A.; Christensen, N.; Chua, S.; Ciolfi, R.; Cirone, A.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colla, A.; Conti, L.; Cortese, S.; Coulon, J.-P.; Cuoco, E.; D'Antonio, S.; Dattilo, V.; Davier, M.; Degallaix, J.; de Laurentis, M.; Deléglise, S.; Del Pozzo, W.; De Rosa, R.; di Fiore, L.; di Giovanni, M.; di Girolamo, T.; di Lieto, A.; di Pace, S.; di Palma, I.; di Renzo, F.; Dolique, V.; Ducrot, M.; Fafone, V.; Farinon, S.; Ferrante, I.; Ferrini, F.; Fidecaro, F.; Fiori, I.; Fiorucci, D.; Flaminio, R.; Fournier, J.-D.; Frasca, S.; Frasconi, F.; Frey, V.; Gammaitoni, L.; Garufi, F.; Gemme, G.; Genin, E.; Gennai, A.; Germain, V.; Ghosh, A.; Ghosh, S.; Giazotto, A.; Gonzalez Castro, J. M.; Gosselin, M.; Gouaty, R.; Grado, A.; Granata, M.; Greco, G.; Groot, P.; Gruning, P.; Guidi, G. M.; Harms, J.; Heidmann, A.; Heitmann, H.; Hello, P.; Hemming, G.; Hoak, D.; Hofman, D.; Huet, D.; Intini, G.; Isac, J.-M.; Jacqmin, T.; Jaranowski, P.; Jonker, R. J. G.; Kéfélian, F.; Khan, I.; Koley, S.; Kowalska, I.; Królak, A.; Kutynia, A.; Lartaux-Vollard, A.; Lazzaro, C.; Leaci, P.; Leonardi, M.; Leroy, N.; Letendre, N.; Lorenzini, M.; Loriette, V.; Losurdo, G.; Lumaca, D.; Majorana, E.; Maksimovic, I.; Man, N.; Mantovani, M.; Marchesoni, F.; Marion, F.; Martelli, F.; Martellini, L.; Masserot, A.; Mastrogiovanni, S.; Meidam, J.; Merzougui, M.; Metzdorff, R.; Mezzani, F.; Michel, C.; Milano, L.; Miller, A.; Minazzoli, O.; Minenkov, Y.; Moggi, A.; Mohan, M.; Montani, M.; Mours, B.; Nardecchia, I.; Naticchioni, L.; Nelemans, G.; Neri, M.; Nichols, D.; Nissanke, S.; Nocera, F.; Palomba, C.; Paoletti, F.; Paoli, A.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patricelli, B.; Pedurand, R.; Perreca, A.; Piccinni, O. J.; Pichot, M.; Piergiovanni, F.; Pillant, G.; Pinard, L.; Poggiani, R.; Popolizio, P.; Porter, E. K.; Prodi, G. A.; Punturo, M.; Puppo, P.; Rapagnani, P.; Razzano, M.; Regimbau, T.; Rei, L.; Ricci, F.; Robinet, F.; Rocchi, A.; Rolland, L.; Romano, R.; Rosińska, D.; Ruggi, P.; Salconi, L.; Sassolas, B.; Schmidt, P.; Sentenac, D.; Sequino, V.; Sieniawska, M.; Singhal, A.; Sorrentino, F.; Stratta, G.; Swinkels, B. L.; Tacca, M.; Tiwari, S.; Tonelli, M.; Travasso, F.; Tringali, M. C.; Trozzo, L.; Tsang, K. W.; van Bakel, N.; van Beuzekom, M.; van den Brand, J. F. J.; van den Broeck, C.; van der Schaaf, L.; van Heijningen, J. V.; Vardaro, M.; Vasúth, M.; Vedovato, G.; Verkindt, D.; Vetrano, F.; Viceré, A.; Vinet, J.-Y.; Vocca, H.; Walet, R.; Wang, G.; Was, M.; Yvert, M.; Zadrożny, A.; Zelenova, T.; Zendri, J.-P.
2017-10-01
Advanced Virgo is the French-Italian second generation laser gravitational wave detector, successor of the Initial Virgo. This new interferometer keeps only the infrastructure of its predecessor and aims to be ten times more sensitive, with its first science run planned for 2017. This article gives an overview of the Advanced Virgo design and the technical choices behind it. Finally, the up-to-date progresses and the planned upgrade for the following years are detailed.
Development of Medical Technology for Contingency Response to Marrow Toxic Agents
2014-05-06
Development of Medical Technology for Contingency Response to Marrow Toxic Agents - Final Performance/Technical Report for January 01, 2011 to...Enhancing HLA Data for Selected Donors 44 IIB.1.6 Maintain a Quality Control Program 44 IIB.2.1 Collection of Primary Data 45 IIB.2.2 Validation of...Receptor Donor Selection KORI Korean LD Linkage Disequilibrium LTA Lymphotoxin Alpha MALDI-TOF Matrix-Assisted Laser Desorption/Ionization – Time Of
In vitro laser nerve repair: protein solder strip irradiation or irradiation alone?
Trickett, I; Dawes, J M; Knowles, D S; Lanzetta, M; Owen, E R
1997-01-01
This study investigated the potential of sutureless nerve repair using two promising laser fusion methods: direct 2 microns irradiation of the epineurium, and protein solder assisted epineurial fusion using a 800 nm laser. Laser anastomosis of the rat sciatic nerve was performed in vitro without stay sutures in two groups of six animals. In the first group, direct laser fusion used a pulsed Cr, Tm: YAG laser. In the second group an albumin-based fluid solder containing the dye indocyanine green was applied to the epineurium, then irradiated with a diode laser. These two techniques were compared with regards to coaptation success and axonal damage. Direct laser welding produced weak bonds despite microscopic investigation of the irradiated nerves showing fusion of the epineurium. The unsatisfactory bonding can be attributed to poor tissue overlap and insufficient protein in the thin epineurium denaturation of underlying axons was also observed. In contrast, the laser solder method produced successful welds with greatly reduced axonal damage, and significantly improved the tensile strength. This study confirmed the technical possibilities of sutureless nerve anastomosis. Laser activated solders enable stronger bonds, by the addition of protein to the anastomosis site, and less thermal damage to underlying tissue through selective absorption of laser energy by dye in the solder. Further in vivo studies are required before drawing final conclusions.
Developments in laser Doppler blood perfusion monitoring
NASA Astrophysics Data System (ADS)
Leahy, Martin J.; de Mul, Frits F. M.; Nilsson, Gert E.; Maniewski, Roman; Liebert, Adam
2003-03-01
This paper reviews the development and use of laser Doppler perfusion monitors and imagers. Despite their great success and almost universal applicability in microcirculation research, they have had great difficulty in converting to widespread clinical application. The enormous interest in microvascular blood perfusion coupled with the 'ease of use' of the technique has led to 2000+ publications citing its use. However, useful results can only be achieved with an understanding of the basic principles of the instrumentation and its application in the various clinical disciplines. The basic technical background is explored and definitions of blood perfusion and laser Doppler perfusion are established. The calibration method is then described together with potential routes to standardisation. A guide to the limitations in application of the technique gives the user a clear indication of what can be achieved in new studies as well as possible inadequacy in some published investigations. Finally some clinical applications have found acceptability and these will be explored.
Surgical Coagulator With Carbon Dioxide Laser For Gynecology
NASA Astrophysics Data System (ADS)
Wolinski, Wieslaw; Kazmirowski, Antoni; Korobowicz, Witold; Olborski, Zbigniew
1987-10-01
The technical data and parameters of the CO2 surgical laser for gynecology are given. Coagulator was designed and constructed in Institute of Microelectronics and Optoelectronics Warsaw Technical University.
Argon dye photocoagulator for microsurgery of the interior structure of the eye
NASA Astrophysics Data System (ADS)
Wolinski, Wieslaw L.; Kazmirowski, Antoni; Kesik, Jerzy; Korobowicz, Witold; Spytkowski, Wojciech
1991-08-01
Argon-dye laser photocoagulator for the microsurgery of the interior structure of the eye is described. Some technical specifications like power stability shape of the spots and the dependence of the power on the tissue vs. wavelenght for dye laser are given. Argon-dye photocoagulator was designed and constructed including argon laser tube and dye laser in Institute of Microelectronics and Optoelectronics Technical University of Warsaw.
Materials Science Clean Room Facility at Tulane University (Final Technical Report)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Altiero, Nicholas
2010-09-30
The project involves conversion of a 3,000 sq. ft. area into a clean room facility for materials science research. It will be accomplished in phases. Phase I will involve preparation of the existing space, acquisition and installation of clean room equipped with a pulsed laser deposition (PLD) processing system, and conversion of ancillary space to facilitate the interface with the clean room. From a capital perspective, Phases II and III will involve the acquisition of additional processing, fabrication, and characterization equipment and capabilities.
Early Risk Reduction Phase 1 FLIR/Laser Designator Window. Revision
1991-12-31
Sandwich-Type FLIR Windows," Air Force AFWAL-TR-83- 4122, Nov 1983. 4-1 Hughes Danbury Optical Systems Final Report, "ATA Window Technology Program," PRBll...Risk Reduction -- Phase I, Optical Properties Measurement Techniques of Three Wide Band Window Materials," 22 August 1991. xii I i 86PR0869 30... Optical Systems, Lexington, MA, 02173, 1 Feb 1991. 5-7 McDonnell Aircraft Company Technical Memorandum TM 256.91.0056.01, "Early Risk Reduction -- Phase
Laser R and D in the armed services
NASA Astrophysics Data System (ADS)
Seidel, R. W.; Bromberg, J. L.
1984-09-01
During the year, September 15, 1983 - September 15, 1984, Dr. Joan Lisa Bromberg has investigated the history of the laser through the interviewing of laser industry pioneers and leaders in California's Bay area and the Murray Hill branch of AT & T's Bell Labs. The status of processing of the interviewee's tapes is listed. During the course of the first year of our project, Dr. Robert W. Seidel has investigated the history of military laser research and development through the exploitation of the Department of Defense's Research and Development data bases, including the Research and Development Plans, Work Unit Information Summaries, and the Technical Report Abstracts of the Defense Technical Information Center; published and unpublished technical reports of military laser research and development available through DTIC and at military installations; visits to military installations and research facilities holding manuscript materials relating to history of laser research and development; and formal and informal interviews with participants in military laser R&D projects.
Oberle, Michael; Wohlwend, Nadia; Jonas, Daniel; Maurer, Florian P; Jost, Geraldine; Tschudin-Sutter, Sarah; Vranckx, Katleen; Egli, Adrian
2016-01-01
The technical, biological, and inter-center reproducibility of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI TOF MS) typing data has not yet been explored. The aim of this study is to compare typing data from multiple centers employing bioinformatics using bacterial strains from two past outbreaks and non-related strains. Participants received twelve extended spectrum betalactamase-producing E. coli isolates and followed the same standard operating procedure (SOP) including a full-protein extraction protocol. All laboratories provided visually read spectra via flexAnalysis (Bruker, Germany). Raw data from each laboratory allowed calculating the technical and biological reproducibility between centers using BioNumerics (Applied Maths NV, Belgium). Technical and biological reproducibility ranged between 96.8-99.4% and 47.6-94.4%, respectively. The inter-center reproducibility showed a comparable clustering among identical isolates. Principal component analysis indicated a higher tendency to cluster within the same center. Therefore, we used a discriminant analysis, which completely separated the clusters. Next, we defined a reference center and performed a statistical analysis to identify specific peaks to identify the outbreak clusters. Finally, we used a classifier algorithm and a linear support vector machine on the determined peaks as classifier. A validation showed that within the set of the reference center, the identification of the cluster was 100% correct with a large contrast between the score with the correct cluster and the next best scoring cluster. Based on the sufficient technical and biological reproducibility of MALDI-TOF MS based spectra, detection of specific clusters is possible from spectra obtained from different centers. However, we believe that a shared SOP and a bioinformatics approach are required to make the analysis robust and reliable.
Method for laser spot welding monitoring
NASA Astrophysics Data System (ADS)
Manassero, Giorgio
1994-09-01
As more powerful solid state laser sources appear on the market, new applications become technically possible and important from the economical point of view. For every process a preliminary optimization phase is necessary. The main parameters, used for a welding application by a high power Nd-YAG laser, are: pulse energy, pulse width, repetition rate and process duration or speed. In this paper an experimental methodology, for the development of an electrooptical laser spot welding monitoring system, is presented. The electromagnetic emission from the molten pool was observed and measured with appropriate sensors. The statistical method `Parameter Design' was used to obtain an accurate analysis of the process parameter that influence process results. A laser station with a solid state laser coupled to an optical fiber (1 mm in diameter) was utilized for the welding tests. The main material used for the experimental plan was zinc coated steel sheet 0.8 mm thick. This material and the related spot welding technique are extensively used in the automotive industry, therefore, the introduction of laser technology in production line will improve the quality of the final product. A correlation, between sensor signals and `through or not through' welds, was assessed. The investigation has furthermore shown the necessity, for the modern laser production systems, to use multisensor heads for process monitoring or control with more advanced signal elaboration procedures.
The simulation study on optical target laser active detection performance
NASA Astrophysics Data System (ADS)
Li, Ying-chun; Hou, Zhao-fei; Fan, Youchen
2014-12-01
According to the working principle of laser active detection system, the paper establishes the optical target laser active detection simulation system, carry out the simulation study on the detection process and detection performance of the system. For instance, the performance model such as the laser emitting, the laser propagation in the atmosphere, the reflection of optical target, the receiver detection system, the signal processing and recognition. We focus on the analysis and modeling the relationship between the laser emitting angle and defocus amount and "cat eye" effect echo laser in the reflection of optical target. Further, in the paper some performance index such as operating range, SNR and the probability of the system have been simulated. The parameters including laser emitting parameters, the reflection of the optical target and the laser propagation in the atmosphere which make a great influence on the performance of the optical target laser active detection system. Finally, using the object-oriented software design methods, the laser active detection system with the opening type, complete function and operating platform, realizes the process simulation that the detection system detect and recognize the optical target, complete the performance simulation of each subsystem, and generate the data report and the graph. It can make the laser active detection system performance models more intuitive because of the visible simulation process. The simulation data obtained from the system provide a reference to adjust the structure of the system parameters. And it provides theoretical and technical support for the top level design of the optical target laser active detection system and performance index optimization.
Research of beam smoothing technology on the technical integration line
NASA Astrophysics Data System (ADS)
Zhang, Rui; Su, Jingqin; Li, Ping; Zhang, Ying; Wang, Jianjun; Dong, Jun; Yang, Dong; Jing, Feng; Xu, Lixin; Ming, Hai
2013-05-01
This paper is focused on the research of SSD and CPP carried out on TIL. A bulk phase modulator with 9.2-GHz modulation frequency is adopted in SSD. The output spectrum of the phase modulator is stable and the residual amplitude modulation is small. FM-to-AM effect caused by free-space propagation after using smoothing by spectral dispersion is theoretically and experimentally studied. Results indicate inserting a dispersion grating in places with larger beam aperture alleviates the FM-to-AM effect, suggesting minimizing free-space propagation and adopting image relay. Experiments indicate when the number of color cycles (Nc) adopts 1, imposing of SSD with 4.26 times diffraction limit (TDL) did not lead to pinhole closure in the spatial filters of the preamplifier with 20 TDL and main amplifier with 26 TDL. Experimental results also indicate SSD didn't influence the load capacity of the laser facility. The contrast of the 440-μm diameter focal spot with 95% energy included using SSD and CPP drops to 0.47, comparing to 1.71 not using SSD and CPP. When the pulse width of the third harmonic wave is 1 ns and the energy is 1115 J, no damage is found in CPP and other final optics. The experiments solves some key technical problems using SSD and CPP on high-power laser facilities, and provides a flexible platform for the laser-plasma interaction experiments.
Solar-pumped laser for free space power transmission
NASA Technical Reports Server (NTRS)
Lee, Ja H.
1989-01-01
Laser power transmission; laser systems; space-borne and available lasers; 2-D and 1 MW laser diode array systems; technical issues; iodine solar pumped laser system; and laser power transmission applications are presented. This presentation is represented by viewgraphs only.
Glue-free assembly of glass fiber reinforced thermoplastics using laser light
NASA Astrophysics Data System (ADS)
Binetruy, C.; Clement, S.; Deleglise, M.; Franz, C.; Knapp, W.; Oumarou, M.; Renard, J.; Roesner, A.
2011-05-01
The use of laser light for bonding of continuous fiber reinforced thermoplastic composites (CFTPC) offers new possibilities to overcome the constraints of conventional joining technologies. Laser bonding is environmentally friendly as no chemical additive or glue is necessary. Accuracy and flexibility of the laser process as well as the quality of the weld seams provide benefits which are already used in many industrial applications. Laser transmission welding has already been introduced in manufacturing of short fiber thermoplastic composites. The laser replaces hot air in tapelaying systems for pre-preg carbon fiber placement. The paper provides an overview concerning the technical basics of the joining process and outline some material inherent characteristics to be considered when using continuous glass fiber reinforced composites The technical feasibility and the mechanical characterization of laser bonded CFTPC are demonstrated. The influence of the different layer configurations on the laser interaction with the material is investigated and the dependency on the mechanical strength of the weld seem is analyzed. The results show that the laser provides an alternative joining technique and offers new perspectives to assemble structural components emerging in automotive or aeronautical manufacturing. It overcomes the environmental and technical difficulties related to existing gluing processes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gui, Ping
During the funding period of this award from May 1, 2014 through March 30, 2016, we have accomplished the design, implementation and measurement results of two laser driver chips: LpGBLD10+ which is a low-power single-channel 10Gb/s laser driver IC, and LDQ10P, which is a 4x10Gb/s driver array chip for High Energy Physics (HEP) applications. With new circuit techniques, the driver consumes a record-low power consumption, 31 mW @10Gb/s/channel and occupies a small area of 400 µm × 1750 µm for the single-channel driver IC and 1900umx1700um for the LDQ10P chip. These characteristics allow for both the LpGBLD10+ ICs and LDQ10P suitable candidatemore » for the Versatile Link PLUS (VL+) project, offering flexibility in configuring multiple Transmitters and receivers.« less
Navigation: National Plans; NAVSTAR-GPS; Laser Gyros
1982-08-31
REFERENC-~CP STER . TECHNICAL REPORT ! "NO. 12686,-’-. - NAVIGATION: NATIONAL PLANS ; NAVSTAR-GPS; LASER GYROS CONTRACT NO. DAAK30-80-C-0073 31 AUGUST...Technical ReportAW Ng. riiNational Plans ; Navstar-GPS; S... : NavstarGPS; a3 Sept 1980 - 31 Aug 1982 ....Lasr Gyros. 6. PERFORMING ORG. REPORT NUMBER PRA...identify by block number) Navigation Navigation Satellites Laser Gyros Position-Location . NAVSTAR-GPS Fiberoptic Gyros Planning Global Positioning System
A compact, efficient, and lightweight laser head for CARLO®: integration, performance, and benefits
NASA Astrophysics Data System (ADS)
Deibel, Waldemar; Schneider, Adrian; Augello, Marcello; Bruno, Alfredo E.; Juergens, Philipp; Cattin, Philippe
2015-09-01
Ever since the first functional lasers were built about 50 years ago, researchers and doctors dream of a medical use for such systems. Today's technology is finally advanced enough to realize these ambitions in a variety of medical fields. There are well-established laser based systems in ophthalmology, dental applications, treatment of kidney stones, and many more. Using lasers presents more than just an alternative to conventional methods for osteotomies. It offers less tissue damage, faster healing times, comparable intervention duration and in consequence improves postoperative treatment of patients. However, there are a few factors that limit routine applications. These technical drawbacks include missing depth control and safe guiding of the laser beam. This paper presents the engineering and integration of a miniaturized laser head for a computer assisted and robot-guided laser osteotome (CARLO®), which can overcome the mentioned drawbacks. The CARLO® device ensures a safe and precise guidance of the laser beam. Such guidance also enables new opportunities and methods, e.g. free geometrical functional cuts, which have the potential to revolutionize bone surgery. The laser head is optimized for beam shaping, target conditioning, working distance, compactness and the integration of all other parts needed, e.g. CCD-cameras for monitoring and referencing, a visible laser for cut simulation, etc. The beam coming out of the laser system is conditioned in shape, energy properties and working distance with an optical arrangement to achieve the desired cutting performance. Here also parameters like optical losses, operating mode, optics materials and long-term stability have are taken into account.
Wolfrum, J
2001-01-01
In recent years a large number of linear and nonlinear laser-based diagnostic techniques for nonintrusive measurements of species concentrations, temperatures, and gas velocities in a wide pressure and temperature range with high temporal and spatial resolution have been developed and have become extremely valuable tools to study many aspects of combustion. Beside the nonintrusive diagnostics of technical combustion devices the kinetics and microscopic dynamics of elementary chemical combustion reactions can be investigated in great detail by laser spectroscopy. These investigations show, that a small number of relatively simple elementary steps like H + O2-->OH + O, H2O2-->2OH, O + N2-->NO + N, NH2 + NO-->H2O + N2, OH + N2H control a large variety of combustion phenomena and pollutant formation processes. Laminar flames are ideal objects to develop the application of laser spectroscopic methods for practical combustion systems and to test and improve the gas-phase reaction mechanism in combustion models. Nonintrusive laser point and field measurements are of basic importance in the validation and further development of turbulent combustion models. Nonlinear laser spectroscopic techniques using infrared-visible sum-frequency generation can now bridge the pressure and materials gap to provide kinetic data for catalytic combustion. Finally, the potential of laser techniques for active combustion control in municipal waste incinerators is illustrated.
Inertial Confinement Fusion Annual Report 1999
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kauffman, Robert L.
The ICF Program has undergone a significant change in 1999 with the decommissioning of the Nova laser and the transfer of much of the experimental program to the OMEGA laser at the University of Rochester. The Nova laser ended operations with the final experiment conducted on May 27, 1999. This marked the end to one of DOE's most successful experimental facilities. Since its commissioning in 1985, Nova performed 13,424 experiments supporting ICF, Defense Sciences, high-power laser research, and basic science research. At the time of its commissioning, Nova was the world's most powerful laser. Its early experiments demonstrated that 3ωmore » light could produce high-drive, low-preheat environment required for indirect-drive ICE. In the early 1990s, the technical program on Nova for indirect drive ignition was defined by the Nova technical contract established by National Academy Review of ICF in 1990. Successful completion of this research program contributed significantly to the recommendation by the ICF Advisory Committee in 1995 to proceed with the construction of the National Ignition Facility? Nova experiments also demonstrated the utility of high-powered lasers for studying the physics of interest to Defense Sciences. Now, high-powered lasers along with pulsed-power machines are the principal facilities for studying high energy density science in DOE's Stockpile Stewardship Program (SSP). In 1997, one beam of Nova was converted to a short pulsed beam producing a petawatt of power in subpicosecond pulses. The petawatt beam was used for pioneering research in short-pulse laser-matter interactions relevant to fast ignitor ICF and short pulsed x-ray, electron, and particle production for use as probes. Nova is being disassembled and the space is being used to support NIF construction. Nova components are being distributed to a number of other laser laboratories around the world for reuse as determined by DOE. This report summarizes the research performed by the ICF Program in FY1999. The report is divided into five sections corresponding to the major areas of program activities. These are sections on (1) ignition target physics experiments theory and modeling, (2) high energy density experimental science, (3) target development, fabrication, and handling, (4) NIF laser development, and (5) optics technology development.« less
NASA Astrophysics Data System (ADS)
Norimatsu, T.; Kozaki, Y.; Shiraga, H.; Fujita, H.; Okano, K.; Members of LIFT Design Team
2017-11-01
We present the conceptual design of an experimental laser fusion plant known as the laser inertial fusion test (LIFT) reactor. The conceptual design aims at technically connecting a single-shot experiment and a commercial power plant. The LIFT reactor is designed on a three-phase scheme, where each phase has specific goals and the dedicated chambers of each phase are driven by the same laser. Technical issues related to the chamber technology including radiation safety to repeat burst mode operation are discussed in this paper.
Health education of population in conection with widespread use of laser radiation
NASA Astrophysics Data System (ADS)
Kashuba, V. A.; Bykhovskiy, A. V.
1984-06-01
Rapid development of laser technology and its adaptation in many areas of national economy make it mandatory to develop a state system of laser safety. Due to absence of visible injuries of those working with laser equipment, a certain degree of bravado has developed among the technical personnel servicing laser instruments. There are no courses available for technicians and professionals concerning safety procedures. To solve this problem, a coordinated program must be organized country-wide with cooperation of physicians, labor safety specialists, preventive medicine experts and hygienists. Stressing the preventive aspects, this effort should lead to development of sound habits and proper technical knowhow.
text only NLC Home Page NLC Technical SLAC Sources Damping Rings S & L Band Linacs Engineering ; Presentations Injector System Documentation Talks and Presentations The NLC ZDR ISG Reports Sources Lasers Photocathodes Electron Source Laser Maintenance Facility Positron Source Sources Technical Notes Sources Meeting
DOT National Transportation Integrated Search
1975-08-01
This report outlines the engineering requirements for an Airborne Laser Remote Sensor for Oil Detection and Classification System. Detailed engineering requirements are given for the major units of the system. Technical considerations pertinent to a ...
ELIMED: a new hadron therapy concept based on laser driven ion beams
NASA Astrophysics Data System (ADS)
Cirrone, Giuseppe A. P.; Margarone, Daniele; Maggiore, Mario; Anzalone, Antonello; Borghesi, Marco; Jia, S. Bijan; Bulanov, Stepan S.; Bulanov, Sergei; Carpinelli, Massimo; Cavallaro, Salvatore; Cutroneo, Mariapompea; Cuttone, Giacomo; Favetta, Marco; Gammino, Santo; Klimo, Ondrej; Manti, Lorenzo; Korn, Georg; La Malfa, Giuseppe; Limpouch, Jiri; Musumarra, Agatino; Petrovic, Ivan; Prokupek, Jan; Psikal, Jan; Ristic-Fira, Aleksandra; Renis, Marcella; Romano, Francesco P.; Romano, Francesco; Schettino, Giuseppe; Schillaci, Francesco; Scuderi, Valentina; Stancampiano, Concetta; Tramontana, Antonella; Ter-Avetisyan, Sargis; Tomasello, Barbara; Torrisi, Lorenzo; Tudisco, Salvo; Velyhan, Andriy
2013-05-01
Laser accelerated proton beams have been proposed to be used in different research fields. A great interest has risen for the potential replacement of conventional accelerating machines with laser-based accelerators, and in particular for the development of new concepts of more compact and cheaper hadrontherapy centers. In this context the ELIMED (ELI MEDical applications) research project has been launched by INFN-LNS and ASCR-FZU researchers within the pan-European ELI-Beamlines facility framework. The ELIMED project aims to demonstrate the potential clinical applicability of optically accelerated proton beams and to realize a laser-accelerated ion transport beamline for multi-disciplinary user applications. In this framework the eye melanoma, as for instance the uveal melanoma normally treated with 62 MeV proton beams produced by standard accelerators, will be considered as a model system to demonstrate the potential clinical use of laser-driven protons in hadrontherapy, especially because of the limited constraints in terms of proton energy and irradiation geometry for this particular tumour treatment. Several challenges, starting from laser-target interaction and beam transport development up to dosimetry and radiobiology, need to be overcome in order to reach the ELIMED final goals. A crucial role will be played by the final design and realization of a transport beamline capable to provide ion beams with proper characteristics in terms of energy spectrum and angular distribution which will allow performing dosimetric tests and biological cell irradiation. A first prototype of the transport beamline has been already designed and other transport elements are under construction in order to perform a first experimental test with the TARANIS laser system by the end of 2013. A wide international collaboration among specialists of different disciplines like Physics, Biology, Chemistry, Medicine and medical doctors coming from Europe, Japan, and the US is growing up around the ELIMED project with the aim to work on the conceptual design, technical and experimental realization of this core beamline of the ELI Beamlines facility.
2017-03-13
support of airborne laser designator use during test and training exercises on military ranges. The initial MATILDA tool, MATILDA PRO Version-1.6.1...was based on the 2007 PRA model developed to perform range safety clearances for the UK Thermal Imaging Airborne Laser Designator (TIALD) system...AFRL Technical Reports. This Technical Report, designated Part I, con- tains documentation of the computational procedures for probabilistic fault
A Survey of Laser Lightning Rod Techniques
1991-08-21
impossibility of the LLR concept. 4 REFERENCES 1. Hagen, 1969: "Diffraction-limited high irradiance Nd- glass laser system, J. Appl. Phys., 40, 511-516. 2. Greig...study", Air Force Flight Dynamics Laboratory,, Technical Report AFFDL-TR-78-60. AD A063 847. 8. Schubert, C.N., Jr. and J.R. Lippert , 1979...pp. 132-135. 9. Lippert , J.R.,1978: "Laser-Induced Lightning Concept Exper- iment", Air Force Flight Dynamics Laboratory, Technical Report AFFDL-TR
Zhang, Zhuang; Zhao, Rujin; Liu, Enhai; Yan, Kun; Ma, Yuebo
2018-06-15
This article presents a new sensor fusion method for visual simultaneous localization and mapping (SLAM) through integration of a monocular camera and a 1D-laser range finder. Such as a fusion method provides the scale estimation and drift correction and it is not limited by volume, e.g., the stereo camera is constrained by the baseline and overcomes the limited depth range problem associated with SLAM for RGBD cameras. We first present the analytical feasibility for estimating the absolute scale through the fusion of 1D distance information and image information. Next, the analytical derivation of the laser-vision fusion is described in detail based on the local dense reconstruction of the image sequences. We also correct the scale drift of the monocular SLAM using the laser distance information which is independent of the drift error. Finally, application of this approach to both indoor and outdoor scenes is verified by the Technical University of Munich dataset of RGBD and self-collected data. We compare the effects of the scale estimation and drift correction of the proposed method with the SLAM for a monocular camera and a RGBD camera.
Thermal management in inertial fusion energy slab amplifiers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sutton, S.B.; Albrecht, G.F.
As the technology associated with the development of solid-state drivers for inertial fusion energy (IFE) has evolved, increased emphasis has been placed on the development of an efficient approach for managing the waste heat generated in the laser media. This paper addresses the technical issues associated with the gas cooling of large aperture slabs, where the laser beam propagates through the cooling fluid. It is shown that the major consequence of proper thermal management is the introduction of simple wedge, or beam steering, into the system. Achieving proper thermal management requires careful consideration of the geometry, cooling fluid characteristics, coolingmore » flow characteristics, as well as the thermal/mechanical/optical characteristics of the laser media. Particularly important are the effects of cooling rate variation and turbulent scattering on the system optical performance. Helium is shown to have an overwhelming advantage with respect to turbulent scattering losses. To mitigate cooling rate variations, the authors introduce the concept of flow conditioning. Finally, optical path length variations across the aperture are calculated. A comparison of two laser materials (S-FAP and YAG) shows the benefit of a nearly a-thermal material on optical variations in the system.« less
A review of laser electrode processing for development and manufacturing of lithium-ion batteries
NASA Astrophysics Data System (ADS)
Pfleging, Wilhelm
2018-02-01
Laser processes for cutting, annealing, structuring, and printing of battery materials have a great potential in order to minimize the fabrication costs and to increase the electrochemical performance and operational lifetime of lithium-ion cells. Hereby, a broad range of applications can be covered such as micro-batteries, mobile applications, electric vehicles, and stand-alone electric energy storage devices. Cost-efficient nanosecond (ns)-laser cutting of electrodes was one of the first laser technologies which were successfully transferred to industrial high-energy battery production. A defined thermal impact can be useful in electrode manufacturing which was demonstrated by laser annealing of thin-film electrodes for adjusting of battery active crystalline phases or by laser-based drying of composite thick-film electrodes for high-energy batteries. Ultrafast or ns-laser direct structuring or printing of electrode materials is a rather new technical approach in order to realize three-dimensional (3D) electrode architectures. Three-dimensional electrode configurations lead to a better electrochemical performance in comparison to conventional 2D one, due to an increased active surface area, reduced mechanical tensions during electrochemical cycling, and an overall reduced cell impedance. Furthermore, it was shown that for thick-film composite electrodes an increase of electrolyte wetting could be achieved by introducing 3D micro-/nano-structures. Laser structuring can turn electrodes into superwicking. This has a positive impact regarding an increased battery lifetime and a reliable battery production. Finally, laser processes can be up-scaled in order to transfer the 3D battery concept to high-energy and high-power lithium-ion cells.
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.
NASA Astrophysics Data System (ADS)
Disselkamp, R. S.; Kelly, J. F.; Sams, R. L.; Anderson, G. A.
Optical feedback to the laser source in tunable diode laser spectroscopy (TDLS) is known to create intensity modulation noise due to elatoning and optical feedback (i.e. multiplicative technical noise) that usually limits spectral signal-to-noise (S/N). The large technical noise often limits absorption spectroscopy to noise floors 100-fold greater than the Poisson shot noise limit due to fluctuations in the laser intensity. The high output powers generated from quantum cascade (QC) lasers, along with their high gain, makes these injection laser systems especially susceptible to technical noise. In this article we discuss a method of using optimal filtering to reduce technical noise. We have observed S/N enhancements ranging from 20% to a factor of 50. The degree to which optimal filtering enhances S/N depends on the similarity between the Fourier components of the technical noise and those of the signal, with lower S/N enhancements observed for more similar Fourier decompositions of the signal and technical noise. We also examine the linearity of optimal filtered spectra in both time and intensity. This was accomplished by creating a synthetic spectrum for the species being studied (CH4, N2O, CO2 and H2O in ambient air) utilizing line positions and linewidths with an assumed Voigt profile from a commercial database (HITRAN). Agreement better than 0.036% in wavenumber and 1.64% in intensity (up to a 260-fold intensity ratio employed) was observed. Our results suggest that rapid ex post facto digital optimal filtering can be used to enhance S/N for routine trace gas detection.
Oberle, Michael; Wohlwend, Nadia; Jonas, Daniel; Maurer, Florian P.; Jost, Geraldine; Tschudin-Sutter, Sarah; Vranckx, Katleen; Egli, Adrian
2016-01-01
Background The technical, biological, and inter-center reproducibility of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI TOF MS) typing data has not yet been explored. The aim of this study is to compare typing data from multiple centers employing bioinformatics using bacterial strains from two past outbreaks and non-related strains. Material/Methods Participants received twelve extended spectrum betalactamase-producing E. coli isolates and followed the same standard operating procedure (SOP) including a full-protein extraction protocol. All laboratories provided visually read spectra via flexAnalysis (Bruker, Germany). Raw data from each laboratory allowed calculating the technical and biological reproducibility between centers using BioNumerics (Applied Maths NV, Belgium). Results Technical and biological reproducibility ranged between 96.8–99.4% and 47.6–94.4%, respectively. The inter-center reproducibility showed a comparable clustering among identical isolates. Principal component analysis indicated a higher tendency to cluster within the same center. Therefore, we used a discriminant analysis, which completely separated the clusters. Next, we defined a reference center and performed a statistical analysis to identify specific peaks to identify the outbreak clusters. Finally, we used a classifier algorithm and a linear support vector machine on the determined peaks as classifier. A validation showed that within the set of the reference center, the identification of the cluster was 100% correct with a large contrast between the score with the correct cluster and the next best scoring cluster. Conclusions Based on the sufficient technical and biological reproducibility of MALDI-TOF MS based spectra, detection of specific clusters is possible from spectra obtained from different centers. However, we believe that a shared SOP and a bioinformatics approach are required to make the analysis robust and reliable. PMID:27798637
2005-05-01
REPORT DATE (DD-MM-VYYVY) 2 . REPORT TYPE 3. DATES COVERED (From - To) 31-05-2005 TECHNICAL-FINAL 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Temporal...Some biochemical studies have investigated free radical formation in the melanosomes of the retinal pigment epithelial (RPE), which are hypothesized to...unpublished). This finding is consistent with others indicating that shorter wavelengths do more damage at equivalent energies. ( 2 ) A tenfold increase in
Independent assessment of laser power beaming options
NASA Technical Reports Server (NTRS)
Ponikvar, Donald R.
1992-01-01
Technical and architectural issues facing a laser power beaming system are discussed. Issues regarding the laser device, optics, beam control, propagation, and lunar site are examined. Environmental and health physics aspects are considered.
Patel, Nitesh V; Mian, Matthew; Stafford, R Jason; Nahed, Brian V; Willie, Jon T; Gross, Robert E; Danish, Shabbar F
2016-12-01
Laser-induced thermal therapy has become a powerful tool in the neurosurgical armamentarium. The physics of laser therapy are complex, but a sound understanding of this topic is clinically relevant, as many centers have incorporated it into their treatment algorithm, and educated patients are demanding consideration of its use for their disease. Laser ablation has been used for a wide array of intracranial lesions. Laser catheter placement is guided by stereotactic planning; however, as the procedure has popularized, the number of ways in which the catheter can be inserted has also increased. There are many technical nuances for laser placement, and, to date, there is not a clear understanding of whether any one technique is better than the other. In this review, we describe the basic physics of magnetic resonance-guided laser-induced thermal therapy and describe the several common techniques for accurate Visualase laser catheter placement in a stepwise fashion. MRg-LITT, magnetic resonance-guided laser-induced thermal therapyPAD, precision aiming device.
Development of highly compact and low power consumption athermal military laser designators
NASA Astrophysics Data System (ADS)
Sijan, A.
2012-10-01
The utility of military lasers, particularly in the area of laser designation for laser-guided weapons, is well understood. Laser systems based on Nd:YAG have been fielded since the 1980's and over the last three decades have introduced incremental technology steps to improve performance and weight. The most recent technology step has been the introduction of athermal lasers based on laser-diode pumping of Nd:YAG and products are now emerging for use on the battlefield. The technical performance, efficiency, size, weight and power for these lasers, has been key to driving the new production designs. In this paper, we review the development of the laser designs and their introduction since the advent of laser designation. In particular, we compare the relative performance and characteristics over the evolution of fielded laser designators. Moreover, we will review the key building blocks for the design of athermal lasers and describe some critical design issues for engineering and productionisation of a military laser system, including removal of thermal lensing, novel diode-pumping schemes and robustness over the environment. These will be exemplified using results from the development of the SELEX Galileo Type 163 Laser Target Designators. These will cover not only technical performance, power and efficiency, but also thermal management, mass, volume, cost and overall complexity for manufacture.
Investigation of possibilities for solar-powered high-energy lasers in space
NASA Technical Reports Server (NTRS)
1982-01-01
Solar pumped lasers were investigated. The literature was reviewed for possible solar laser candidates from optical pumping experiments. A baseline CO electric discharge laser system was shown to be technically feasible. The most promising direct solar pumped laser was identified to be CF3I. Using the 'STAG' solar laser concept and CF3I, it was found that such a system could be weight competitive with the baseline CO laser system.
Development of laser technology in Poland: 2016
NASA Astrophysics Data System (ADS)
Jankiewicz, Zdzisław; Jabczyński, Jan K.; Romaniuk, Ryszard S.
2016-12-01
The paper is an introduction to the volume of proceedings and a concise digest of works presented during the XIth National Symposium on Laser Technology (SLT2016) [1]. The Symposium is organized since 1984 every three years [2-8]. SLT2016 was organized by the Institute of Optoelectronics, Military University of Technology (IO, WAT) [9], Warsaw, with cooperation of Warsaw University of Technology (WUT) [10], in Jastarnia on 27-30 September 2016. Symposium Proceedings are traditionally published by SPIE [11-19]. The meeting has gathered around 150 participants who presented around 120 research and technical papers. The Symposium, organized every 3 years is a good portrait of laser technology and laser applications development in Poland at university laboratories, governmental institutes, company R&D laboratories, etc. The SLT also presents the current technical projects under realization by the national research, development and industrial teams. Topical tracks of the Symposium, traditionally divided to two large areas - sources and applications, were: laser sources in near and medium infrared, picosecond and femtosecond lasers, optical fiber lasers and amplifiers, semiconductor lasers, high power and high energy lasers and their applications, new materials and components for laser technology, applications of laser technology in measurements, metrology and science, military applications of laser technology, laser applications in environment protection and remote detection of trace substances, laser applications in medicine and biomedical engineering, laser applications in industry, technologies and material engineering.
Lasers for nonlinear microscopy.
Wise, Frank
2013-03-01
Various versions of nonlinear microscopy are revolutionizing the life sciences, almost all of which are made possible because of the development of ultrafast lasers. In this article, the main properties and technical features of short-pulse lasers used in nonlinear microscopy are summarized. Recent research results on fiber lasers that will impact future instruments are also discussed.
The measurement of atmospheric visibility with Lidar: TSC field test results
DOT National Transportation Integrated Search
1974-03-01
The report represents a technical feasibility study of the use of lidar for determining the atmospheric extinction coefficient in low visibility. Measurements were made with three laser sources: a Q-switched ruby laser, a GaAlAs diode laser array, an...
Essay: Robert H. Siemann As Leader of the Advanced Accelerator Research Department
DOE Office of Scientific and Technical Information (OSTI.GOV)
Colby, Eric R.; Hogan, Mark J.; /SLAC
Robert H. Siemann originally conceived of the Advanced Accelerator Research Department (AARD) as an academic, experimental group dedicated to probing the technical limitations of accelerators while providing excellent educational opportunities for young scientists. The early years of the Accelerator Research Department B, as it was then known, were dedicated to a wealth of mostly student-led experiments to examine the promise of advanced accelerator techniques. High-gradient techniques including millimeter-wave rf acceleration, beam-driven plasma acceleration, and direct laser acceleration were pursued, including tests of materials under rf pulsed heating and short-pulse laser radiation, to establish the ultimate limitations on gradient. As themore » department and program grew, so did the motivation to found an accelerator research center that brought experimentalists together in a test facility environment to conduct a broad range of experiments. The Final Focus Test Beam and later the Next Linear Collider Test Accelerator provided unique experimental facilities for AARD staff and collaborators to carry out advanced accelerator experiments. Throughout the evolution of this dynamic program, Bob maintained a department atmosphere and culture more reminiscent of a university research group than a national laboratory department. His exceptional ability to balance multiple roles as scientist, professor, and administrator enabled the creation and preservation of an environment that fostered technical innovation and scholarship.« less
Lincoln Advanced Science and Engineering Reinforcement (LASER) program
NASA Technical Reports Server (NTRS)
Williams, Willie E.
1989-01-01
Lincoln University, under the Lincoln Advanced Science and Engineering Reinforcement (LASER) Program, has identified and successfully recruited over 100 students for majors in technical fields. To date, over 70 percent of these students have completed or will complete technical degrees in engineering, physics, chemistry, and computer science. Of those completing the undergraduate degree, over 40 percent have gone on to graduate and professional schools. This success is attributable to well planned approaches to student recruitment, training, personal motivation, retention, and program staff. Very closely coupled to the above factors is a focus designed to achieve excellence in program services and student performance. Future contributions by the LASER Program to the pool of technical minority graduates will have a significant impact. This is already evident from the success of the students that began the first year of the program. With program plans to refine many of the already successful techniques, follow-on activities are expected to make even greater contributions to the availability of technically trained minorities. For example, undergraduate research exposure, broadened summer, and co-op work experiences will be enhanced.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Glasser, Alan H.
Final technical report on DE-SC0016106. This is the final technical report for a portion of the multi-institutional CEMM project. This report is centered around 3 publications and a seminar presentation, which have been submitted to E-Link.
Results of EUREKA project STILMED: transfer to standards
NASA Astrophysics Data System (ADS)
Woellmer, Wolfgang
1996-12-01
The final results of the German part of the joint project STILMED 'Safety Technology in Laser Medicine' are available and being prepared for publication. The question is raised, if parts of these results may be subject to international standards. An overview is given for the structure and procedure of national, European and international standardization. Existing standards are considered concerning their relationship to STILMED, which dealt with the chemical, particulate and microbiological composition and possible hazards of laser plume, as well as protection means, like plume evacuators, including the development of nozzles and instruments with integrated evacuation channels, and face masks. Results of basic research and experiences with medical treatment modalities are not matter for standardization. On the other hand, plume evacuators and their technical data should be submitted to standards, which define test procedures for their performance and safety. Also, surgical face masks, for which no international standards exists, could be well suited for standardization, although the multitude of application conditions would make it an excessive task. At least, products that claim 'for laser use' or 'laserproof' or similar should fulfill standardized requirements, and the respective wording needs protection by standard definition.
10 CFR 52.157 - Contents of applications; technical information in final safety analysis report.
Code of Federal Regulations, 2013 CFR
2013-01-01
...; technical information in final safety analysis report. The application must contain a final safety analysis...) Information sufficient to demonstrate compliance with the applicable requirements regarding testing, analysis... 10 Energy 2 2013-01-01 2013-01-01 false Contents of applications; technical information in final...
10 CFR 52.157 - Contents of applications; technical information in final safety analysis report.
Code of Federal Regulations, 2012 CFR
2012-01-01
...; technical information in final safety analysis report. The application must contain a final safety analysis...) Information sufficient to demonstrate compliance with the applicable requirements regarding testing, analysis... 10 Energy 2 2012-01-01 2012-01-01 false Contents of applications; technical information in final...
10 CFR 52.157 - Contents of applications; technical information in final safety analysis report.
Code of Federal Regulations, 2014 CFR
2014-01-01
...; technical information in final safety analysis report. The application must contain a final safety analysis...) Information sufficient to demonstrate compliance with the applicable requirements regarding testing, analysis... 10 Energy 2 2014-01-01 2014-01-01 false Contents of applications; technical information in final...
10 CFR 52.157 - Contents of applications; technical information in final safety analysis report.
Code of Federal Regulations, 2011 CFR
2011-01-01
...; technical information in final safety analysis report. The application must contain a final safety analysis...) Information sufficient to demonstrate compliance with the applicable requirements regarding testing, analysis... 10 Energy 2 2011-01-01 2011-01-01 false Contents of applications; technical information in final...
RL-34 ring laser gyro laboratory evaluation for the Deep Space Network antenna application
NASA Technical Reports Server (NTRS)
1991-01-01
The overall results of this laboratory evaluation are quite encouraging. The gyro data is in good agreement with the system's overall pointing performance, which is quite close to the technical objectives for the Deep Space Network (DSN) application. The system can be calibrated to the levels required for millidegree levels of pointing performance, and initialization performance is within the required 0.001 degree objective. The blind target acquisition performance is within a factor of two of the 0.0001 degree objective, limited only by a combination of the slow rate (0.5 deg/sec) and the existing production quantization logic (0.38 arc-sec/pulse). Logic circuitry exists to better this performance such that it will better the objective by 50 percent. Representative data with this circuitry has been provided for illustration. Target tracking performance is about twice the one millidegree objective, with several factors contributing. The first factor is the bias stability of the gyros, which is exceptional, but will limit performance to the 0.001 and 0.002 degree range for long tracking periods. The second contributing factor is the accelerometer contributions when the system is elevated. These degrade performance into the 0.003 to 0.004 degree range, which could be improved upon with some additional changes. Finally, we have provided a set of recommendations to improve performance closer to the technical objectives. These recommendations include gyro, electronics, and system configurational changes that form the basis for additional work to achieve the desired performance. In conclusion, we believe that the RL-34 ring laser gyro-based advanced navigation system demonstrated performance consistent with expectations and technical objectives, and it has the potential for even further enhancement for the DSN application.
1992-02-21
Contents: Applications, IR Pumped Visible Lasers, Blue-Green Diode Emitters, Materials, Poster Session, Frequency Conversion in Bulk Devices, Gas Lasers, and Frequency Conversion in Guided-Wave Devices.
Comparison of working efficiency of terrestrial laser scanner in day and night conditions
NASA Astrophysics Data System (ADS)
Arslan, A. E.; Kalkan, K.
2013-10-01
Terrestrial Laser Scanning is a popular and widely used technique to scan existing objects, document historical sites and items, and remodel them if and when needed. Their ability to collect thousands of point data per second makes them an invaluable tool in many areas from engineering to historical reconstruction. There are many scanners in the market with different technical specifications. One main technical specification of laser scanners is range and illumination. In this study, it is tested to be determined the optimal working times of a laser scanner and the scanners consistency with its specifications sheet. In order to conduct this work, series of GNSS measurements in Istanbul Technical University have been carried out, connected to the national reference network, to determine precise positions of target points and the scanner, which makes possible to define a precise distance between the scanner and targets. Those ground surveys has been used for calibration and registration purposes. Two different scan campaigns conducted at 12 am and 11 pm to compare working efficiency of laser scanner in different illumination conditions and targets are measured with a handheld spectro-radiometer in order to determine their reflective characteristics. The obtained results are compared and their accuracies have been analysed.
Diode laser absorption sensors for gas-dynamic and combustion flows
NASA Technical Reports Server (NTRS)
Allen, M. G.
1998-01-01
Recent advances in room-temperature, near-IR and visible diode laser sources for tele-communication, high-speed computer networks, and optical data storage applications are enabling a new generation of gas-dynamic and combustion-flow sensors based on laser absorption spectroscopy. In addition to conventional species concentration and density measurements, spectroscopic techniques for temperature, velocity, pressure and mass flux have been demonstrated in laboratory, industrial and technical flows. Combined with fibreoptic distribution networks and ultrasensitive detection strategies, compact and portable sensors are now appearing for a variety of applications. In many cases, the superior spectroscopic quality of the new laser sources compared with earlier cryogenic, mid-IR devices is allowing increased sensitivity of trace species measurements, high-precision spectroscopy of major gas constituents, and stable, autonomous measurement systems. The purpose of this article is to review recent progress in this field and suggest likely directions for future research and development. The various laser-source technologies are briefly reviewed as they relate to sensor applications. Basic theory for laser absorption measurements of gas-dynamic properties is reviewed and special detection strategies for the weak near-IR and visible absorption spectra are described. Typical sensor configurations are described and compared for various application scenarios, ranging from laboratory research to automated field and airborne packages. Recent applications of gas-dynamic sensors for air flows and fluxes of trace atmospheric species are presented. Applications of gas-dynamic and combustion sensors to research and development of high-speed flows aeropropulsion engines, and combustion emissions monitoring are presented in detail, along with emerging flow control systems based on these new sensors. Finally, technology in nonlinear frequency conversion, UV laser materials, room-temperature mid-IR materials and broadly tunable multisection devices is reviewed to suggest new sensor possibilities.
NASA Astrophysics Data System (ADS)
Bronder, T.; Miller, H.; Stohs, J.; Lu, C.; Baker, J.; Lucero, A.
The development of a reliable and effective laser source for pumping mesospheric sodium to generate an artificial guidestar has been well documented. From the early achievements with 589nm high-power dye lasers at the Keck and Lick observatories to the ground-breaking 50W CW FASOR (Frequency Addition Source of Optical Radiation) Guidestar at the Air Forces Starfire Optical Range (SOR), there has been intense interest in this technology from both the academic and military communities. Beginning in the fall of 2008, the Air Force Research Laboratorys Advanced Electric Lasers Branch began a project to build, test, verify and deliver an upgraded version of the SOR FASOR for use at the AF Maui Optical Station (AMOS) in the summer of 2010. This FASOR will be similar in design to the existing SOR device and produce 50W of diffraction limited, linearly polarized narrow linewidth 589nm light by combining the output of two injection-locked Nd:YAG ring lasers (operating at 1064nm and 1319nm) using resonant sum-frequency generation in a lithium triborate crystal (LBO). The upgraded features will include modularized sub-components, embedded control electronics, and a simplified cooling system. The first portion of this upgrade project is to reconstruct the current SOR FASOR components and include improved methods of regulating the gain modules of the two injection lasers. In parallel with this effort, the technical plans for the modularization and re-packaging of the FASOR will be finalized and coordinated with the staff at Maui. This presentation will summarize the result of these efforts to date and provide updates on the AMOS FASOR status. Additionally, plans for "next-generation" FASOR upgrades for both SOR and AMOS will also be discussed.
Developing and Modeling Fiber Amplifier Arrays
2006-09-01
15. A. E. Siegman , Lasers , University Science Books, ISBN 0-935702-11-5, pg 734. 16. Jianye Lu, et al, “A new method of coherent summation of laser ... Laser Division This report is published in the interest of scientific and technical information exchange...STATEMENT Approved for public release; distribution is unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT High Energy Lasers (HEL) are required for
Technical Aspects Related to the Application of SFM Photogrammetry in High Mountain
NASA Astrophysics Data System (ADS)
Scaioni, M.; Crippa, J.; Corti, M.; Barazzetti, L.; Fugazza, D.; Azzoni, R.; Cernuschi, M.; Diolaiuti, G. A.
2018-05-01
Structure-from-Motion (SfM) photogrammetry is a flexible and powerful tool to provide 3D point clouds describing the surface of objects. Due to the easy transportability and low-cost of necessary equipment with respect to laser scanning techniques, SfM photogrammetry has great potential to be applied in harsh high-mountain environment. Here point clouds and derived by-products (DEM's, orthoimages, Virtual-Reality models) are needed to document surface morphology and to investigate dynamic processes such as landslides, avalanches, river and soil erosion, glacier retreat. On the other hand, from both the literature and the direct experience of the authors, there are some technical issues that still deserve thorough investigations. The paper would like to address some open problems and suggest solutions, in particular on regards of the photogrammetric network design, the strategy for georeferencing the final products, and for their comparison within time. The discussion is documented with some examples, mainly from surveying campaigns at the Forni Glacier in Italian Alps.
Villavicencio, Alan T; Burneikiene, Sigita; Babuska, Jason M; Nelson, Ewell L; Mason, Alexander; Rajpal, Sharad
2015-04-01
The purpose of this study was to evaluate potential technical advantages of the CO2 laser technology in mini-open transforaminal lumbar interbody fusion (TLIF) surgeries and report our preliminary clinical data on the safety and clinical outcomes. There is currently no literature discussing the recently redeveloped CO2 laser technology application for lumbar fusion. Safety and clinical outcomes were compared between two groups: 24 patients that underwent CO2 laser-assisted one-level TLIF surgeries and 30 patients that underwent standard one-level TLIF surgeries without the laser. There were no neural thermal injuries or other intraoperative laser-related complications encountered in this cohort of patients. At a mean follow-up of 17.4 months, significantly reduced lower back pain scores (P=0.013) were reported in the laser-assisted patient group compared to a standard fusion patient group. Lower extremity radicular pain intensity scores were similar in both groups. Laser-assisted TLIF surgeries showed a tendency (P = 0.07) of shorter operative times that was not statistically significant. Based on this preliminary clinical report, the safety of the CO2 laser device for lumbar fusion surgeries was assessed. There were no neural thermal injuries or other intraoperative laser-related complications encountered in this cohort of patients. Further investigation of CO2 laser-assisted lumbar fusion procedures is warranted in order to evaluate its effect on clinical outcomes.
Laser technologies in ophthalmic surgery
NASA Astrophysics Data System (ADS)
Atezhev, V. V.; Barchunov, B. V.; Vartapetov, S. K.; Zav'yalov, A. S.; Lapshin, K. E.; Movshev, V. G.; Shcherbakov, I. A.
2016-08-01
Excimer and femtosecond lasers are widely used in ophthalmology to correct refraction. Laser systems for vision correction are based on versatile technical solutions and include multiple hard- and software components. Laser characteristics, properties of laser beam delivery system, algorithms for cornea treatment, and methods of pre-surgical diagnostics determine the surgical outcome. Here we describe the scientific and technological basis for laser systems for refractive surgery developed at the Physics Instrumentation Center (PIC) at the Prokhorov General Physics Institute (GPI), Russian Academy of Sciences.
NASA Astrophysics Data System (ADS)
Faure, Benoît; Durand, Eric; Maurice, Sylvestre; Bruneau, Didier; Montmessin, Franck
2017-11-01
ChemCam is a LIBS Instrument mounted on the MSL 2011 NASA mission. The laser transmitter of this Instrument has been developed by the French society Thales Optronique (former Thales Laser) with a strong technical support from CNES. The paper will first rapidly present the performance of this laser and will then describe the postChemCam developments realized on and around this laser for new planetology programs.
Laser Science & Technology Program Annual Report - 2000
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, H-L
2001-03-20
The Laser Science and Technology (LS&T) Program Annual Report 2001 provides documentation of the achievements of the LLNL LS&T Program during the April 2001 to March 2002 period using three formats: (1) an Overview that is a narrative summary of important results for the year; (2) brief summaries of research and development activity highlights within the four Program elements: Advanced Lasers and Components (AL&C), Laser Optics and Materials (LO&M), Short Pulse Laser Applications and Technologies (SPLAT), and High-Energy Laser System and Tests (HELST); and (3) a compilation of selected articles and technical reports published in reputable scientific or technology journalsmore » in this period. All three elements (Annual Overview, Activity Highlights, and Technical Reports) are also on the Web: http://laser.llnl.gov/lasers/pubs/icfq.html. The underlying mission for the LS&T Program is to develop advanced lasers, optics, and materials technologies and applications to solve problems and create new capabilities of importance to the Laboratory and the nation. This mission statement has been our guide for defining work appropriate for our Program. A major new focus of LS&T beginning this past year has been the development of high peak power short-pulse capability for the National Ignition Facility (NIF). LS&T is committed to this activity.« less
Laser manufacturing: strategies for dealing with the challenges
NASA Astrophysics Data System (ADS)
Barr, John R. M.
2012-09-01
Laser manufacturing in Edinburgh was initiated in 1963 by Ferranti (one of the previous names for SELEX Galileo). Since 2003 a modernized range of military lasers has been established. Innovation, both technical and in other aspects of the business, has enabled the design and manufacture of world leading laser designators and countermeasure lasers. Specific examples will be given including: the application of Geometric Algebra to resonator design; novel alignment free optical parametric oscillators; techniques for designing thermally insensitive laser diode pump heads; and methods for contamination control in lasers.
NASA Astrophysics Data System (ADS)
Simcik, John C.
1989-04-01
Texas State Technical Institute-Waco (TSTI-WACO) was the first school in the United States to offer an Associate of Applied Science degree in Laser Electro-Optics Technology. The program began in September 1969 and has produced 1,827 graduates since inception. These graduates are readily adaptable to any area of the laser electro-optics industry. Areas of study include Optics, Electronics, Vacuum, Physics, Mathematics, and English with emphasis on Electro-Optics. Graduate placement is centered around research and development, life sciences and manufacturing in technical and engineering areas.
Quasi four-level Tm:LuAG laser
NASA Technical Reports Server (NTRS)
Jani, Mahendra G. (Inventor); Barnes, Norman P. (Inventor); Hutcheson, Ralph L. (Inventor); Rodriguez, Waldo J. (Inventor)
1997-01-01
A quasi four-level solid-state laser is provided. A laser crystal is disposed in a laser cavity. The laser crystal has a LuAG-based host material doped to a final concentration between about 2% and about 7% thulium (Tm) ions. For the more heavily doped final concentrations, the LuAG-based host material is a LuAG seed crystal doped with a small concentration of Tm ions. Laser diode arrays are disposed transversely to the laser crystal for energizing the Tm ions.
A Laser Technology Program Does Not Start with the Speed of Light.
ERIC Educational Resources Information Center
Gebert, John H.
1982-01-01
Describes the personnel, equipment, and facilities problems encountered by North Central Technical Institute in the development of a laser technician program, and the program's enrollment and job placement rates. Advocates financial support for such programs to meet the national demand for laser and other high technology personnel. (WL)
Advanced helium magnetometer for space applications
NASA Technical Reports Server (NTRS)
Slocum, Robert E.
1987-01-01
The goal of this effort was demonstration of the concepts for an advanced helium magnetometer which meets the demands of future NASA earth orbiting, interplanetary, solar, and interstellar missions. The technical effort focused on optical pumping of helium with tunable solid state lasers. We were able to demonstrate the concept of a laser pumped helium magnetometer with improved accuracy, low power, and sensitivity of the order of 1 pT. A number of technical approaches were investigated for building a solid state laser tunable to the helium absorption line at 1083 nm. The laser selected was an Nd-doped LNA crystal pumped by a diode laser. Two laboratory versions of the lanthanum neodymium hexa-aluminate (LNA) laser were fabricated and used to conduct optical pumping experiments in helium and demonstrate laser pumped magnetometer concepts for both the low field vector mode and the scalar mode of operation. A digital resonance spectrometer was designed and built in order to evaluate the helium resonance signals and observe scalar magnetometer operation. The results indicate that the laser pumped sensor in the VHM mode is 45 times more sensitive than a lamp pumped sensor for identical system noise levels. A study was made of typical laser pumped resonance signals in the conventional magnetic resonance mode. The laser pumped sensor was operated as a scalar magnetometer, and it is concluded that magnetometers with 1 pT sensitivity can be achieved with the use of laser pumping and stable laser pump sources.
Hybrid laser arc welding: State-of-art review
NASA Astrophysics Data System (ADS)
Acherjee, Bappa
2018-02-01
Hybrid laser arc welding simultaneously utilizes the arc welding and the laser welding, in a common interaction zone. The synergic effects of laser beam and eclectic arc in the same weld pool results in an increase of welding speed and penetration depth along with the enhancement of gap bridging capability and process stability. This paper presents the current status of this hybrid technique in terms of research, developments and applications. Effort is made to present a comprehensive technical know-how about this process through a systematic review of research articles, industrial catalogues, technical notes, etc. In the introductory part of the review, an overview of the hybrid laser arc welding is presented, including operation principle, process requirements, historical developments, benefits and drawbacks of the process. This is followed by a detailed discussion on control parameters those govern the performance of hybrid laser arc welding process. Thereafter, a report of improvements of performance and weld qualities achieved by using hybrid welding process is presented based on review of several research papers. The succeeding sections furnish the examples of industrial applications and the concluding remarks.
Solid-State, High Energy 2-Micron Laser Development for Space-Based Remote Sensing
NASA Technical Reports Server (NTRS)
Singh, Upendra N.
2010-01-01
Lidar (light detection and ranging) remote sensing enjoys the advantages of excellent vertical and horizontal resolution; pointing capability; a signal source independent from natural light; and control and knowledge of transmitted wavelength, pulse shape, and polarization and received polarization. Lidar in space is an emerging technology now being developing to fit applications where passive sensors cannot meet current measurement requirements. Technical requirements for space lidar are more demanding than for ground-based or airborne systems. Perhaps the most distinguishing characteristics of space lidars are the environmental requirements. Space lidar systems must be specially designed to survive the mechanical vibration loads of launch and operate in the vacuum of space where exposure to ionizing radiation limits the electronic components available. Finally, space lidars must be designed to be highly reliable because they must operate without the need for repair or adjustment. Lifetime requirements tend to be important drivers of the overall system design. The maturity of the required technologies is a key to the development of any space lidar system. NASA entered a new era in the 1990 s with the approval of several space-based remote sensing missions employing laser radar (lidar) techniques. Following the steps of passive remote sensing and then active radar remote sensing, lidar sensors were a logical next step, providing independence from natural light sources, and better spatial resolution and smaller sensor size than radar sensors. The shorter electromagnetic wavelengths of laser light also allowed signal reflectance from air molecules and aerosol particles. The smaller receiver apertures allowed the concept of scanning the sensor field of view. However, technical problems with several space-based lidar missions during that decade led to concern at NASA about the risk of lidar missions. An external panel was convened to make recommendations to NASA. Their report in 2000 strongly advocated that NASA maintain in-house laser and lidar capability, and that NASA should work to lower the technology risk for all future lidar missions. A multi-Center NASA team formulated an integrated NASA strategy to provide the technology and maturity of systems necessary to make Lidar/Laser systems viable for space-based study and monitoring of the Earth's atmosphere. In 2002 the NASA Earth Science Enterprise (ESE) and Office of Aerospace Technology (OAT) created the Laser Risk Reduction Program (LRRP) and directed NASA Langley Research Center (LaRC) and Goddard Space Flight Center to carry out synergistic and complementary research towards solid-state lasers/lidars developments for space-based remote sensing applications.
Laser beam distribution system for the HiLASE Center
NASA Astrophysics Data System (ADS)
Macúchová, Karolina; Heřmánek, Jan; Kaufman, Jan; Muresan, Mihai-George; Růžička, Jan; Řeháková, Martina; Divoký, Martin; Švandrlík, Luděk.; Mocek, Tomáś
2017-12-01
We report recent progress in design and testing of a distribution system for high-power laser beam delivery developed within the HiLASE project of the IOP in the Czech Republic. Laser beam distribution system is a technical system allowing safe and precise distribution of different laser beams from laboratories to several experimental stations. The unique nature of HiLASE lasers requires new approach, which makes design of the distribution system a state-of-the-art challenge.
Henry Taube and Coordination Chemistry
Shifts Caused by Cr++ in Aqueous Solutions, DOE Technical Report, 1962 Reactions of Solvated Ions Final Report, DOE Technical Report, 1962 Isotopic Discrimination of Some Solutes in Liquid Ammonia, DOE Technical Report, 1966 Final Technical Report of Research, DOE Technical Report, 1972 Top Additional Web
George A. Olah, Carbocation and Hydrocarbon Chemistry
. Final Technical Report. [HF:BF{sub 2}/H{sub 2}] , DOE Technical Report, 1980 Superacid Catalyzed Coal Conversion Chemistry. 1st and 2nd Quarterly Technical Progress Reports, September 1, 1983-March 30, 1984 , DOE Technical Report, 1984 Superacid Catalyzed Coal Conversion Chemistry. Final Technical Report
Holographically Encoded Volume Phase Masks
2015-07-13
Lu et al., “Coherent beam combination of fiber laser arrays via multiplexed volume Bragg gratings,” in Conf. on Lasers and Electro- Optics: Science...combining of fiber lasers using multiplexed volume Bragg gratings,” in Conf. on Lasers and Electro- Optics: Science and Innovations, OSA Technical Digest...satisfying the Bragg condition of the hologram. Moreover, this approach enables the capability to encode and multiplex several phase masks into a single
NASA Astrophysics Data System (ADS)
Elton, Raymond C.
Theoretical and practical aspects of X-ray lasers are discussed in an introduction emphasizing recent advances. Chapters are devoted to the unique optical properties of the X-ray spectral region, the principles of short-wavelength lasers, pumping by exciting plasma ions, pumping by electron capture into excited ionic states, pumping by ionization of atoms and ions, and alternative approaches. The potential scientific, technical, biological, and medical applications of X-ray lasers are briefly characterized.
NASA Astrophysics Data System (ADS)
Kalejs, J. P.
1994-03-01
This report describes work to advance the manufacturing line capabilities in crystal growth and laser cutting of Mobil Solar's unique edge-defined film-fed growth (EFG) octagon technology and to reduce the manufacturing costs of 10 cm x 10 cm polycrystalline silicon EFG wafers. The report summarizes the significant technical improvements in EFG technology achieved in the first 6 months of the PVMaT Phase 2 and the success in meeting program milestones. Technical results are reported for each of the three main pregrain areas: Task 5 -- Thin octagon growth (crystal growth) to reduce the thickness of the octagon to 200 microns; Task 6 -- Laser cutting-to improve the laser cutting process so as to produce wafers with decreased laser cutting damage at increased wafer throughput rates; and Task 7 -- Process control and product specification to implement advanced strategies in crystal growth process control and productivity designed to increase wafer yields.
77 FR 46306 - Fluxapyroxad; Pesticide Tolerances Technical Amendment
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-03
...; Pesticide Tolerances Technical Amendment AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule; technical amendment. SUMMARY: EPA issued a final rule in the Federal Register of May 14, 2012, concerning.... Inadvertently, the terminology for the oilseed crop group and for dried plums was incorrect. This technical...
NASA Astrophysics Data System (ADS)
Malavallon, Olivier
1995-04-01
Laser beam stripping can be achieved using several active materials: YAG, CO2 Tea, or Excimer. The YAG laser appears to be the most efficient laser assessed in this report. However, the results obtained for productivity, quality, and type of stripping were very poor. Also, for stripping and on account of its specifications, the laser beam can only be used in an automated manner. In spite of these results, it seems that certain companies in Europe have recently developed technical solutions allowing better results to be obtained.
2016-06-01
TECHNICAL REPORT Algorithm for Automatic Detection, Localization and Characterization of Magnetic Dipole Targets Using the Laser Scalar...Automatic Detection, Localization and Characterization of Magnetic Dipole Targets Using the Laser Scalar Gradiometer Leon Vaizer, Jesse Angle, Neil...of Magnetic Dipole Targets Using LSG i June 2016 TABLE OF CONTENTS INTRODUCTION
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kalejs, J.P.
1994-06-01
Mobil Solar Energy Corporation manufactures photovoltaic modules based on its unique Edge-defined Film-fed Growth (EFG) process for producing octagon-shaped hollow polycrystalline silicon tubes. The octagons are cut by lasers into 100 mm x 100 mm wafers which are suitable for solar cell processing. This process avoids slicing, grinding and polishing operations which are wasteful of material and are typical of most other wafer production methods. EFG wafers are fabricated into solar cells and modules using processes that have been specially developed to allow scaling up to high throughput rates. The goals of the Photovoltaic Manufacturing Technology Initiative (PVMaT) program atmore » Mobil Solar were to improve the EFG manufacturing line through technology advances that accelerate cost reduction in production and stimulate market growth for its product. The program was structured into three main tasks: to decrease silicon utilization by lowering wafer thickness from 400 to 200 {mu}m; to enhance laser cutting yields and throughput while improving the wafer strength; and to raise crystal growth productivity and yield. The technical problems faced and the advances made in the Mobil Solar PVMaT program are described. The author concludes with a presentation of the results of a detailed cost model for EFT module production. This model describes the accelerated reductions in manufacturing costs which are already in place and the future benefits anticipated to result from the technical achievements of the PVMaT program.« less
Yeo, Caitlin T; Ungi, Tamas; U-Thainual, Paweena; Lasso, Andras; McGraw, Robert C; Fichtinger, Gabor
2011-07-01
The purpose of this study was to determine if augmented reality image overlay and laser guidance systems can assist medical trainees in learning the correct placement of a needle for percutaneous facet joint injection. The Perk Station training suite was used to conduct and record the needle insertion procedures. A total of 40 volunteers were randomized into two groups of 20. 1) The Overlay group received a training session that consisted of four insertions with image and laser guidance, followed by two insertions with laser overlay only. 2) The Control group received a training session of six classical freehand insertions. Both groups then conducted two freehand insertions. The movement of the needle was tracked during the series of insertions. The final insertion procedure was assessed to determine if there was a benefit to the overlay method compared to the freehand insertions. The Overlay group had a better success rate (83.3% versus 68.4%, p=0.002), and potential for less tissue damage as measured by the amount of needle movement inside the phantom (3077.6 mm(2) versus 5607.9 mm(2) , p =0.01). These results suggest that an augmented reality overlay guidance system can assist medical trainees in acquiring technical competence in a percutaneous needle insertion procedure. © 2011 IEEE
Thermal Analysis and Microhardness Mapping in Hybrid Laser Welds in a Structural Steel
2003-01-01
conditions. Via the keyhole the laser beam brings about easier ignition of the arc, stabilization of the arc welding process, and penetration of the...with respect to the conventional GMAW or GTAW processes without the need for very close fit-up. This paper will compare an autogenous laser weld to a...UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP017864 TITLE: Thermal Analysis and Microhardness Mapping in Hybrid Laser
1992-06-01
Geisler, M. H . Haken, Univ. Stuttgar’, Germany. A geometrical formulation P. Sorenson, P. L. Christiansen, Technical Univ., Denmark; J. of phase...locking, L. A. mode inhomogeneously broadened laser dynamics, B. Melnikov, G. N. Tatarkov, Chernyshevsky State Univ., Russia. Meziane, H . Ladjouze, ENSSAT...coupled laser arrays, D. Nichols, H . Winful, Univ. Michigan. We have studied the effect of nonlinear TuC6 Phase singularities in a Fabry-Perot resonator
Overview and future direction for blackbody solar-pumped lasers
NASA Technical Reports Server (NTRS)
Deyoung, R. J.
1988-01-01
A review of solar-pumped blackbody lasers is given which addresses their present status and suggests future research directions. The blackbody laser concept is one system proposed to scale to multimegawatt power levels for space-to-space power transmissions for such applications as onboard spacecraft electrical or propulsion needs. Among the critical technical issues are the scalability to high powers and the laser wavelength which impacts the transmission optics size as well as the laser-to-electric converter at the receiver. Because present blackbody solar-pumped lasers will have laser wavelengths longer than 4 microns, simple photovoltaic converters cannot be used, and transmission optics will be large. Thus, future blackbody laser systems should emphasize near visible laser wavelengths.
Power beaming research at NASA
NASA Technical Reports Server (NTRS)
Rather, John D. G.
1992-01-01
NASA's current research activities to evaluate laser power beaming systems are summarized with regard to their applications of greatest interest. Key technical certainties and uncertainties pertaining to laser power beaming systems appropriate for space applications are quantified. A path of development is presented that includes maturation of key technology components for reliable laser and millimeter wave power beaming systems during the 1990s.
Modeling of Flowing Plasmas and Pulse Power Schemes for O2(1Delta) Production for Chemical Lasers
2008-01-19
Project (0704-0188) Washington, DC 20503. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. R E P O R T D A T E (D D -M M Y Y M 2 . R E P O R T T Y P... E . U mI 2 00AJL r- r - u g u s 2 0 0 7 Final Technical Report 1i September 2005- 31 August 2007 4. TITLE AND SUBTITLE Sa. CONTRACT NUMBER Modeling...should be near 1.2 eV, which corresponds to an E /N of t10 Townsend [ 1 Townsend (Td) = 101 7 V-cm 2]. Self-sustained discharges in He/0 2 mixtures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schmehl, Russell H.
2016-03-02
This is the final technical report for a project carried out at Tulane University of New Orleans that describes the development of light induced (solar) reactions geared toward decomposing water into its component elements : hydrogen and oxygen. Much of the work involved optimizing systems for absorbing visible light and undergoing light promoted reactions to generate very strong reducing agents that are capable of reacting with water to produce hydrogen. Additional portions of the research were collaborative efforts to put the strong reducing agents to work in reaction with hydrogen generation catalysts prepared elsewhere. Time resolved laser spectroscopic methods weremore » used to evaluate the light induced reactions and characterize very reactive intermediate substances formed during the reactions.« less
Stephan, Thomas; Trappitsch, Reto; Davis, Andrew M.; ...
2016-06-17
Here, we describe CHILI, the Chicago Instrument for Laser Ionization, a new resonance ionization mass spectrometer developed for isotopic analysis at high spatial resolution and high sensitivity of small samples like contemporary interstellar dust grains returned by the Stardust spacecraft. We explain how CHILI addresses the technical challenges associated with such analyses by pushing most technical specifications towards their physical limits. As an initial demonstration, after many years of designing and developing CHILI, we have analyzed presolar silicon carbide grains for their isotopic compositions of strontium, zirconium, and barium. Subsequently, after further technical improvements, we have used CHILI to analyze,more » for the first time without interference, all stable isotopes of iron and nickel simultaneously in presolar silicon carbide grains. With a special timing scheme for the ionization lasers, we separated iron and nickel isotopes in the time-of-flight spectrum such that the isobaric interference between 58Fe and 58Ni was resolved. In-depth discussion of the astrophysical implications of the presolar grain results is deferred to dedicated later publications. Here we focus on the technical aspects of CHILI, its status quo, and further developments necessary to achieve CHILI’s ultimate goals, 10 nm lateral resolution and 30–40% useful yield.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stephan, Thomas; Trappitsch, Reto; Davis, Andrew M.
2016-08-01
We describe CHILI, the Chicago Instrument for Laser Ionization, a new resonance ionization mass spectrometer developed for isotopic analysis at high spatial resolution and high sensitivity of small samples like contemporary interstellar dust grains returned by the Stardust spacecraft. We explain how CHILI addresses the technical challenges associated with such analyses by pushing most technical specifications towards their physical limits. As an initial demonstration, after many years of designing and developing CHILI, we have analyzed presolar silicon carbide grains for their isotopic compositions of strontium, zirconium, and barium. Subsequently, after further technical improvements, we have used CHILI to analyze, formore » the first time without interference, all stable isotopes of iron and nickel simultaneously in presolar silicon carbide grains. With a special timing scheme for the ionization lasers, we separated iron and nickel isotopes in the time-of-flight spectrum such that the isobaric interference between Fe-58 and Ni-58 was resolved. In-depth discussion of the astrophysical implications of the presolar grain results is deferred to dedicated later publications. Here we focus on the technical aspects of CHILI, its status quo, and further developments necessary to achieve CHILI's ultimate goals, similar to 10 nm lateral resolution and 30-40% useful yield.« less
Lidar systems for measuring visibility : a technical assessment
DOT National Transportation Integrated Search
1974-09-01
A study has been made of the feasibility of using a laser backscatter system (lidar) to measure slant visibility at airports. This report summarizes the present status of lidar from a technical standpoint. Based largely on the results of experimental...
Formation and Properties of Laser-Induced Periodic Surface Structures on Different Glasses.
Gräf, Stephan; Kunz, Clemens; Müller, Frank A
2017-08-10
The formation and properties of laser-induced periodic surface structures (LIPSS) was investigated on different technically relevant glasses including fused silica, borosilicate glass, and soda-lime-silicate glass under irradiation of fs-laser pulses characterized by a pulse duration τ = 300 fs and a laser wavelength λ = 1025 nm. For this purpose, LIPSS were fabricated in an air environment at normal incidence with different laser peak fluence, pulse number, and repetition frequency. The generated structures were characterized by using optical microscopy, scanning electron microscopy, focused ion beam preparation and Fast-Fourier transformation. The results reveal the formation of LIPSS on all investigated glasses. LIPSS formation on soda-lime-silicate glass is determined by remarkable melt-formation as an intra-pulse effect. Differences between the different glasses concerning the appearing structures, their spatial period and their morphology were discussed based on the non-linear absorption behavior and the temperature-dependent viscosity. The findings facilitate the fabrication of tailored LIPSS-based surface structures on different technically relevant glasses that could be of particular interest for various applications.
Formation and Properties of Laser-Induced Periodic Surface Structures on Different Glasses
Kunz, Clemens; Müller, Frank A.
2017-01-01
The formation and properties of laser-induced periodic surface structures (LIPSS) was investigated on different technically relevant glasses including fused silica, borosilicate glass, and soda-lime-silicate glass under irradiation of fs-laser pulses characterized by a pulse duration τ = 300 fs and a laser wavelength λ = 1025 nm. For this purpose, LIPSS were fabricated in an air environment at normal incidence with different laser peak fluence, pulse number, and repetition frequency. The generated structures were characterized by using optical microscopy, scanning electron microscopy, focused ion beam preparation and Fast-Fourier transformation. The results reveal the formation of LIPSS on all investigated glasses. LIPSS formation on soda-lime-silicate glass is determined by remarkable melt-formation as an intra-pulse effect. Differences between the different glasses concerning the appearing structures, their spatial period and their morphology were discussed based on the non-linear absorption behavior and the temperature-dependent viscosity. The findings facilitate the fabrication of tailored LIPSS-based surface structures on different technically relevant glasses that could be of particular interest for various applications. PMID:28796180
Darmanis, Spyridon; Toms, Andrew; Durman, Robert; Moore, Donna; Eyres, Keith
2007-07-01
To reduce the operating time in computer-assisted navigated total knee replacement (TKR), by improving communication between the infrared camera and the trackers placed on the patient. The innovation involves placing a routinely used laser pointer on top of the camera, so that the infrared cameras focus precisely on the trackers located on the knee to be operated on. A prospective randomized study was performed involving 40 patients divided into two groups, A and B. Both groups underwent navigated TKR, but for group B patients a laser pointer was used to improve the targeting capabilities of the cameras. Without the laser pointer, the camera had to move a mean 9.2 times in order to identify the trackers. With the introduction of the laser pointer, this was reduced to 0.9 times. Accordingly, the additional mean time required without the laser pointer was 11.6 minutes. Time delays are a major problem in computer-assisted surgery, and our technical suggestion can contribute towards reducing the delays associated with this particular application.
Small lasers in flow cytometry.
Telford, William G
2004-01-01
Laser technology has made tremendous advances in recent years, particularly in the area of diode and diode-pumped solid state sources. Flow cytometry has been a direct beneficiary of these advances, as these small, low-maintenance, inexpensive lasers with reasonable power outputs are integrated into flow cytometers. In this chapter we review the contribution and potential of solid-state lasers to flow cytometry, and show several examples of these novel sources integrated into production flow cytometers. Technical details and critical parameters for successful application of these lasers for biomedical analysis are reviewed.
Code of Federal Regulations, 2014 CFR
2014-07-01
... How is the final performance report to be sent to the Defense Technical Information Center? (a... 32 National Defense 1 2014-07-01 2014-07-01 false How is the final performance report to be sent to the Defense Technical Information Center? 37.895 Section 37.895 National Defense Department of...
Code of Federal Regulations, 2011 CFR
2011-07-01
... How is the final performance report to be sent to the Defense Technical Information Center? (a... 32 National Defense 1 2011-07-01 2011-07-01 false How is the final performance report to be sent to the Defense Technical Information Center? 37.895 Section 37.895 National Defense Department of...
Code of Federal Regulations, 2013 CFR
2013-07-01
... How is the final performance report to be sent to the Defense Technical Information Center? (a... 32 National Defense 1 2013-07-01 2013-07-01 false How is the final performance report to be sent to the Defense Technical Information Center? 37.895 Section 37.895 National Defense Department of...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 32 National Defense 1 2012-07-01 2012-07-01 false How is the final performance report to be sent to the Defense Technical Information Center? 37.895 Section 37.895 National Defense Department of... How is the final performance report to be sent to the Defense Technical Information Center? (a...
Ultrafast Laser System for Producing on-Demand Single-and Multi-Photon Quantum States
2015-09-20
14-Mar-2015 Approved for Public Release; Distribution Unlimited Final Report: Ultrafast laser system for producing on-demand single- and multi...Champaign, IL 61820 -7406 14-Mar-2015 ABSTRACT Number of Papers published in peer-reviewed journals: Final Report: Ultrafast laser system for producing
Mauri, Giovanni; Sconfienza, Luca Maria; Pescatori, Lorenzo Carlo; Fedeli, Maria Paola; Alì, Marco; Di Leo, Giovanni; Sardanelli, Francesco
2017-08-01
To systematically review studies concerning imaging-guided minimally-invasive breast cancer treatments. An online database search was performed for English-language articles evaluating percutaneous breast cancer ablation. Pooled data and 95% confidence intervals (CIs) were calculated. Technical success, technique efficacy, minor and major complications were analysed, including ablation technique subgroup analysis and effect of tumour size on outcome. Forty-five studies were analysed, including 1,156 patients and 1,168 lesions. Radiofrequency (n=577; 50%), microwaves (n=78; 7%), laser (n=227; 19%), cryoablation (n=156; 13%) and high-intensity focused ultrasound (HIFU, n=129; 11%) were used. Pooled technical success was 96% (95%CI 94-97%) [laser=98% (95-99%); HIFU=96% (90-98%); radiofrequency=96% (93-97%); cryoablation=95% (90-98%); microwave=93% (81-98%)]. Pooled technique efficacy was 75% (67-81%) [radiofrequency=82% (74-88); cryoablation=75% (51-90); laser=59% (35-79); HIFU=49% (26-74)]. Major complications pooled rate was 6% (4-8). Minor complications pooled rate was 8% (5-13%). Differences between techniques were not significant for technical success (p=0.449), major complications (p=0.181) or minor complications (p=0.762), but significant for technique efficacy (p=0.009). Tumour size did not impact on variables (p>0.142). Imaging-guided percutaneous ablation techniques of breast cancer have a high rate of technical success, while technique efficacy remains suboptimal. Complication rates are relatively low. • Imaging-guided ablation techniques for breast cancer are 96% technically successful. • Overall technique efficacy rate is 75% but largely inhomogeneous among studies. • Overall major and minor complication rates are low (6-8%).
Laser Integration on Silicon Photonic Circuits Through Transfer Printing
2017-03-10
AFRL-AFOSR-UK-TR-2017-0019 Laser integration on silicon photonic circuits through transfer printing Gunther Roelkens UNIVERSITEIT GENT VZW Final...TYPE Final 3. DATES COVERED (From - To) 15 Sep 2015 to 14 Sep 2016 4. TITLE AND SUBTITLE Laser integration on silicon photonic circuits through...parallel integration of III-V lasers on silicon photonic integrated circuits. The report discusses the technological process that has been developed as
1975-09-01
being conducted with highly- stripped carbon ions emitted fron a laser -irradiated surface and ^xpandin- into a background gas . The...obtained from reported measurement s of noble gas lasers indicate that the amplifiers will operate in I depletion mode, providing pulse powers in the...pumping appears to be the easier alternative and it will be pursued. The alternative amplifier approach involving electron beam pumped noble gas lasers
Proof of the Feasibility of Coherent and Incoherent Schemes for Pumping a Gamma-Ray Laser
1988-07-01
DIP!; ilLE-CWPj AD-A 799 638 The University of Texas at DallasCenter for Quantlin, Electronics The Gamma-Ray Laser Project Quarterly Report April...AND INCOHERENT SCHEMES FOR PUMPING A GAMMA-RAY LASER Principal Investigator: Carl B. Collins The University of Texas at Dallas Center for Quantum...FEASIBILITY OF Quarterly Technical Progress COHERENT AND INCOHERENT SCHEMES /I/RR - 61WARA FOR PUMPING A GAMMA-RAY LASER 6.PERFORMINO ORG. REPORT NUMBER
Innovative CO2 LASER-Based Pavement Striping and Stripe Removal
DOT National Transportation Integrated Search
2014-07-01
This is a Technical Report of an FY2014 NDOT funded project on Innovative CO2 Laserbased Pavement Striping and Stripe Removal. The project was concerned with adopting the laser technology for pavement stripe and markers removal and inferring on its e...
Litscher, Gerhard
2012-01-01
At the moment, modernization of acupuncture has a high priority. On the traditional side, acupuncture has only recently been awarded the status of Intangible Cultural Heritage by the UNESCO. On the innovative side, high-tech acupuncture is a registered trademark in Austria. Acupuncture has been used for medical treatment for thousands of years. A large number of empirical data are available but the technical quantification of effects was not possible up to now. Using electroacupuncture, needle, or laser stimulation and modern biomedical techniques, it was possible for the first time to quantify changes in biological activities caused by acupuncture. This paper which serves as introduction for the special issue "High-Tech Acupuncture and Integrative Laser Medicine" of the present journal, focuses on the latest innovative aspects that underline the further enhancement and development of acupuncture. Special emphasis is given to new methodological and technical investigations, for example, results obtained from all kinds of acupuncture innovations (e.g., teleacupuncture) and integrative laser medicine.
Litscher, Gerhard
2012-01-01
At the moment, modernization of acupuncture has a high priority. On the traditional side, acupuncture has only recently been awarded the status of Intangible Cultural Heritage by the UNESCO. On the innovative side, high-tech acupuncture is a registered trademark in Austria. Acupuncture has been used for medical treatment for thousands of years. A large number of empirical data are available but the technical quantification of effects was not possible up to now. Using electroacupuncture, needle, or laser stimulation and modern biomedical techniques, it was possible for the first time to quantify changes in biological activities caused by acupuncture. This paper which serves as introduction for the special issue “High-Tech Acupuncture and Integrative Laser Medicine” of the present journal, focuses on the latest innovative aspects that underline the further enhancement and development of acupuncture. Special emphasis is given to new methodological and technical investigations, for example, results obtained from all kinds of acupuncture innovations (e.g., teleacupuncture) and integrative laser medicine. PMID:22570669
76 FR 18624 - Research, Technical Assistance and Training Programs: Notice of Final Circular
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-04
... to FTA Circular 6100.1D, Research and Technical Assistance Training Program: Application Instructions... DEPARTMENT OF TRANSPORTATION Federal Transit Administration Research, Technical Assistance and Training Programs: Notice of Final Circular AGENCY: Federal Transit Administration (FTA), DOT. ACTION...
Biomedical effects of low-power laser controlled by electroacupuncture
NASA Astrophysics Data System (ADS)
Kalenchits, Nadezhda I.; Nicolaenko, Andrej A.; Shpilevoj, Boris N.
1997-12-01
The methods and technical facilities of testing the biomedical effects caused by the influence of low-power laser radiation in the process of laser therapy are presented. Described studies have been conducted by means of the complex of fireware facilities consisting of the system of electroacupuncture diagnostics (EA) and a system of laser therapy on the basis of multichannel laser and magneto-laser devices. The task of laser therapy was concluded in undertaking acupuncture anaesthetization, achievement of antioedemic and dispersional actions, raising tone of musculus and nervous system, normalization of immunity factors under the control of system EA. The 82 percent to 95 percent agreement of the result of an electroacupuncture diagnostics with clinical diagnoses were achieved.
Diode-laser-based therapy device
NASA Astrophysics Data System (ADS)
Udrea, Mircea V.; Nica, Adriana S.; Florian, Mariana; Poenaru, Daniela; Udrea, Gabriela; Lungeanu, Mihaela; Sporea, Dan G.; Vasiliu, Virgil V.; Vieru, Roxana
2004-10-01
A new therapy laser device is presented. The device consists of a central unit and different types of laser probes. The laser probe model SL7-650 delivers seven red (650 nm), 5 mW diode lasers convergent beams. The beams converge at about 30 cm in front of the laser probe and the irradiated area might be varied by simple displacement of the laser probe with respect to the target. The laser probe SL1-808 emits single infrared laser beam up to 500 mW. The efficiency of the use of this device in physiotherapy, and rheumatology, has been put into evidence after years of testing. Dermatology and microsurgery are users of infrared powerful laser probes. The device has successfully passed technical and clinical tests in order to be certified. The laser device design and some medical results are given.
Status of 2 micron laser technology program
NASA Technical Reports Server (NTRS)
Storm, Mark
1991-01-01
The status of 2 micron lasers for windshear detection is described in viewgraph form Theoretical atmospheric and instrument system studies have demonstrated that the 2.1 micron Ho:YAG lasers can effectively measure wind speeds in both wet and dry conditions with accuracies of 1 m/sec. Two micron laser technology looks very promising in the near future, but several technical questions remain. The Ho:YAG laser would be small, compact, and efficient, requiring little or no maintenance. Since the Ho:YAG laser is laser diode pumped and has no moving part, the lifetime of this laser would be directly related to the diode laser lifetimes which can perform in excess of 10,000 hours. Efficiencies of 3 to 12 percent are expected, but laser demonstrations confirming the ability to Q-switch this laser are required. Coherent laser operation has been demonstrated for both the CW and Q-switched lasers.
The use of laser in hysteroscopic surgery.
Nappi, Luigi; Sorrentino, Felice; Angioni, Stefano; Pontis, Alessandro; Greco, Pantaleo
2016-12-01
The term laser, an acronym for light amplification by stimulated emission of radiation, covers a wide range of devices. Lasers are commonly described by the emitted wavelength that covers the entire light spectrum from infrared to ultraviolet and the active lasing medium. Currently, over forty different types of lasers have found application in medicine. Moreover, advances made by gynecologists in the field of operative hysteroscopy have developed a very great interest in the use of surgical lasers. Technical improvements in hysteroscopes and lasers have led several gynecologists to evaluate their use in the surgical treatment of intrauterine pathologies. This narrative review concerns the most common used lasers in hysteroscopic surgery with particular attention to the latest promising results of the laser technology.
Minnesota Deaf-Blind Technical Assistance Project. Final Report.
ERIC Educational Resources Information Center
Kloos, Eric
This final report describes activities and accomplishments of the 3-year federally supported Minnesota Deaf-Blind Technical Assistance Project. The project provided training and technical assistance, information sharing, and support services to families of children with deaf-blindness. Activities and accomplishments included: collaboration with…
75 FR 56857 - Pilot, Flight Instructor, and Pilot School Certification
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-17
... of part 141. Discussion of Technical Amendment Section 141.5(d) establishes the quality of training... Certification AGENCY: Federal Aviation Administration, DOT. ACTION: Final rule; technical amendment. SUMMARY: The Federal Aviation Administration (FAA) is making minor technical changes to a final rule published...
Yang, R G; Zhang, J; Zhai, Z H; Zhai, S Q; Liu, K; Gao, J R
2015-08-10
Low-frequency (Hz~kHz) squeezing is very important in many schemes of quantum precision measurement. But it is more difficult than that at megahertz-frequency because of the introduction of laser low-frequency technical noise. In this paper, we propose a scheme to obtain a low-frequency signal beyond the quantum limit from the frequency comb in a non-degenerate frequency and degenerate polarization optical parametric amplifier (NOPA) operating below threshold with type I phase matching by frequency-shift detection. Low-frequency squeezing immune to laser technical noise is obtained by a detection system with a local beam of two-frequency intense laser. Furthermore, the low-frequency squeezing can be used for phase measurement in Mach-Zehnder interferometer, and the signal-to-noise ratio (SNR) can be enhanced greatly.
Development of Smart Precision Forest in Conifer Plantation in Japan Using Laser Scanning Data
NASA Astrophysics Data System (ADS)
Katoh, M.; Deng, S.; Takenaka, Y.; Cheung, K.; Oono, K.; Horisawa, M.; Hyyppä, J.; Yu, X.; Liang, X.; Wang, Y.
2017-10-01
Currently, the authors are planning to launch a consortium effort toward Japan's first smart precision forestry project using laser data and to develop this technology throughout the country. Smart precision forestry information gathered using the Nagano model (laser scanning from aircraft, drone, and backpack) is being developed to improve the sophistication of forest information, reduce labor-intensive work, maintain sustainable timber productivity, and facilitate supply chain management by laser sensing information in collaboration with industry, academia, and government. In this paper, we outline the research project and the technical development situation of unmanned aerial vehicle laser scanning.
1997 Technical Digest Series. Volume 7: Applications of High Field and Short Wavelength Sources VII
1997-03-01
clusters irradiated with ultrashort , high intensity laser pulses can exhibit "ionization ig- nition" which leads...8, 9]. 25-atom Ne clusters and 25-atom Ar clusters are modelled as irradiated by a 800 nm, 15 fs (fwhm) laser pulse with peak intensities ranging...Measurements of the spatial and spectral properties of ultrashort , intense laser pulses propagating in underdense plasmas demonstrate
77 FR 29247 - Federal Motor Vehicle Safety Standards; Occupant Crash Protection
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-17
...). ACTION: Final rule; technical amendments. SUMMARY: This final rule makes technical amendments to Federal... advanced air bag requirements. As written now, the general warning label requirements contain an explicit... equipment requirements for restraint systems. This document makes technical amendments to several of the...
Laser System Technician. A Catalog of Performance Objectives and Performance Guides.
ERIC Educational Resources Information Center
Florida State Dept. of Education, Tallahassee. Div. of Vocational, Adult, and Community Education.
This Vocational-Technical Education Consortium of States (V-TECS) catalog contains the state-of-the-art tasks and standards of performance for the occupation of laser system technician. It provides the curriculum specialist or instructor with the foundation for instructional development. Performance objectives and performance guides are provided…
NASA Astrophysics Data System (ADS)
Kuetemeyer, K.; Lucas-Hahn, A.; Petersen, B.; Hassel, P.; Lemme, E.; Niemann, H.; Heisterkamp, A.
2010-02-01
Cloning of several mammalian species has been achieved by somatic cell nuclear transfer over the last decade. However, this method still results in very low efficiencies originating from biological and technical aspects. The highly-invasive mechanical enucleation belongs to the technical aspects and requires considerable micromanipulation skill. In this paper, we present a novel non-invasive method for combined oocyte imaging and automated functional enucleation using femtosecond (fs) laser pulses. After three-dimensional imaging of Hoechst-labeled porcine oocytes by multiphoton microscopy, our self-developed software automatically determined the metaphase plate position and shape. Subsequent irradiation of this volume with the very same laser at higher pulse energies in the low-density-plasma regime was used for metaphase plate ablation. We show that functional fs laser-based enucleation of porcine oocytes completely inhibited further embryonic development while maintaining intact oocyte morphology. In contrast, non-irradiated oocytes were able to develop to the blastocyst stage without significant differences to control oocytes. Our results indicate that fs laser systems offer great potential for oocyte imaging and enucleation as a fast, easy to use and reliable tool which may improve the efficiency of somatic cell clone production.
Kijsamanmith, Kanittha; Timpawat, Siriporn; Vongsavan, Noppakun; Matthews, Bruce
2011-06-01
To compare red (635 nm) and infrared (780 nm) light for recording pulpal blood flow from human anterior teeth with a laser Doppler flow meter. Recordings were made from 7 healthy teeth in 5 subjects (aged 22-55 years) using a laser Doppler flow meter (Periflux 4001) equipped with both red and infrared lasers. Average blood flow signals were obtained with both light sources alternately from each tooth under five conditions: intact tooth without opaque rubber dam, intact tooth with dam, after injecting local anaesthetic (3% Mepivacaine) (LA) over the apex of the tooth and cavity preparation to almost expose the pulp, after removal and replacement of the pulp, and with the root canal empty. With infrared light, because of technical limitations, data were obtained for the first three conditions only. The dam significantly decreased the mean blood flow by 82%. Injecting LA and cavity preparation had no significant effect. With red light, dam produced a decrease of 56%, and the resulting signal was reduced by 33% after LA and cavity preparation. The remaining signal fell by 46% after pulp removal and replacement. This contribution of the pulp is similar to that recorded previously with infrared light. There was no significant further change when the pulp was finally removed. The importance of using opaque rubber dam is confirmed. With dam, there is no advantage to using red rather than infrared light, and in each case the pulp contributes less than 50% to the blood flow signal. Copyright © 2011 Elsevier Ltd. All rights reserved.
Cryogenic Yb: YAG Thin-Disk Laser
2016-09-09
AFRL-RD-PS- TP-2016-0004 AFRL-RD-PS- TP-2016-0004 CRYOGENIC Yb: YAG THINN-DISK LASER N . Vretenar, et al. 19 August 2011 Technical Paper...Cryogenic Yb: YAG Thin-Disk Laser 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) * N . Vretenar, R. Carson, ***T. Lucas, T. Newell, W.P. Latham...Thin-Disk Laser N . Vretenar,1 T. Carson,2 T. Lucas,3T. Newell,2 W. P. Latham,2 and P. Peterson,3 H. Bostanci,4 J. J. Lindauer4, B. A. Saarloos,4
Ursescu, Daniel; Cheriaux, G.; Audebert, P.; ...
2017-01-01
The Laser Beam Delivery (LBD) system technical design report covers the interface between the High Power Laser System (HPLS) and the experiments, together with the pulse quality management. Here, the laser transport part of the LBD has a number of subsystems as follows: the beam transport lines for the six main outputs of HPLS, the additional short and long pulses and the synchronization system including the timing of the laser pulses with the Gamma Beam System (GBS) and the experiments on femtosecond timescale. Pulse quality management, discussed further here, consist in the generation and delivery of multiple HPLS pulses, coherentmore » combining of the HPLS arms, laser pulse diagnostics on target, laser beam dumps, shutters and output energy adaption.« less
1979-11-23
Entered) ACKNOWLEDGMENTS The author hereby expresses his appreciation to Mr. J. A. Schaeffel Jr. for his guidance on interferometry and the computer...were collected by an automated laser speckle interferometry displacement contour analyzer developed by John A. Schaeffel , Jr. [3]. The new method of 10...Fringe Patterns, US Army Missile Command, Redstone Arsenal, Alabama, Technical Report RL-76-18, 20 April 1976. 3. Schaeffel , J. A., Automated Laser
2012-02-24
AND SUBTITLE Detection of Biochemical Pathogens, Laser Stand-off Spectroscopy, Quantum Coherence, and Many Body Quantum Optics 6. AUTHORS Marian O...Maximum 200 words) Results of our earlier research in the realm of quantum optics were extended in order to solve the challenging technical problems of...efficient methods of generating UV light via quantum coherence. 14. SUBJECT TERMS Quantum coherence, quantum optics, lasers 15. NUMBER OF PAGES 15
Customer Overview of Pulsed Laser Heating for Evaluation of Gun Bore Materials
2015-05-01
Technical Report ARWSB-TR-15003 Customer Overview of Pulsed Laser Heating for Evaluation of Gun Bore Materials Mark E. Todaro...SUBTITLE Customer Overview of Pulsed Laser Heating for Evaluation of Gun Bore Materials 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...thermomechanical effects that occur at the bore of large and medium caliber guns during firing. Hence, PLH has been used not only to gain insight into the erosion
Kawakubo, Kazumichi; Kawakami, Hiroshi; Toyokawa, Yoshihide; Otani, Koichi; Kuwatani, Masaki; Abe, Yoko; Kawahata, Shuhei; Kubo, Kimitoshi; Kubota, Yoshimasa; Sakamoto, Naoya
2015-01-01
Endoscopic double self-expandable metallic stent (SEMS) placement by the partial stent-in-stent (PSIS) method has been reported to be useful for the management of unresectable hilar malignant biliary obstruction. However, it is technically challenging, and the optimal SEMS for the procedure remains unknown. The aim of this study was to identify the risk factors for technical failure of endoscopic double SEMS placement for unresectable malignant hilar biliary obstruction (MHBO). Between December 2009 and May 2013, 50 consecutive patients with MHBO underwent endoscopic double SEMS placement by the PSIS method. We retrospectively evaluated the rate of successful double SEMS placement and identified the risk factors for technical failure. The technical success rate for double SEMS placement was 82.0% (95% confidence interval [CI]: 69.2-90.2). On univariate analysis, the rate of technical failure was high in patients with metastatic disease and unilateral placement. Multivariate analysis revealed that metastatic disease was a significant risk factor for technical failure (odds ratio: 9.63, 95% CI: 1.11-105.5). The subgroup analysis after double guidewire insertion showed that the rate of technical success was higher in the laser-cut type SEMS with a large mesh and thick delivery system than in the braided type SEMS with a small mesh and thick delivery system. Metastatic disease was a significant risk factor for technical failure of double SEMS placement for unresectable MHBO. The laser-cut type SEMS with a large mesh and thin delivery system might be preferable for the PSIS procedure. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.
Constructing a Low-budget Laser Axotomy System to Study Axon Regeneration in C. elegans
Williams, Wes; Nix, Paola; Bastiani, Michael
2011-01-01
Laser axotomy followed by time-lapse microscopy is a sensitive assay for axon regeneration phenotypes in C. elegans1. The main difficulty of this assay is the perceived cost ($25-100K) and technical expertise required for implementing a laser ablation system2,3. However, solid-state pulse lasers of modest costs (<$10K) can provide robust performance for laser ablation in transparent preparations where target axons are "close" to the tissue surface. Construction and alignment of a system can be accomplished in a day. The optical path provided by light from the focused condenser to the ablation laser provides a convenient alignment guide. An intermediate module with all optics removed can be dedicated to the ablation laser and assures that no optical elements need be moved during a laser ablation session. A dichroic in the intermediate module allows simultaneous imaging and laser ablation. Centering the laser beam to the outgoing beam from the focused microscope condenser lens guides the initial alignment of the system. A variety of lenses are used to condition and expand the laser beam to fill the back aperture of the chosen objective lens. Final alignment and testing is performed with a front surface mirrored glass slide target. Laser power is adjusted to give a minimum size ablation spot (<1um). The ablation spot is centered with fine adjustments of the last kinematically mounted mirror to cross hairs fixed in the imaging window. Laser power for axotomy will be approximately 10X higher than needed for the minimum ablation spot on the target slide (this may vary with the target you use). Worms can be immobilized for laser axotomy and time-lapse imaging by mounting on agarose pads (or in microfluidic chambers4). Agarose pads are easily made with 10% agarose in balanced saline melted in a microwave. A drop of molten agarose is placed on a glass slide and flattened with another glass slide into a pad approximately 200 um thick (a single layer of time tape on adjacent slides is used as a spacer). A "Sharpie" cap is used to cut out a uniformed diameter circular pad of 13mm. Anesthetic (1ul Muscimol 20mM) and Microspheres (Chris Fang-Yen personal communication) (1ul 2.65% Polystyrene 0.1 um in water) are added to the center of the pad followed by 3-5 worms oriented so they are lying on their left sides. A glass coverslip is applied and then Vaseline is used to seal the coverslip and prevent evaporation of the sample. PMID:22126922
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hedman, P.O.; Smoot, L.D.; Smith, P.J.
1987-10-15
The general purpose of this research program was to develop a basic understanding of the physical and chemical processes in entrained coal gasification and to use the results to improve and evaluate an entrained gasification computer model. The first task included the collection and analysis of in-situ gasifier data at elevated pressures with three coal types (North Dakota lignite, Wyoming subbituminous and Illinois bituminous), the design, construction, and testing of new coal/oxygen/steam injectors with a fourth coal type (Utah bituminous), the collection of supporting turbulent fluid dynamic (LDV) data from cold-flow studies, and the investigation of the feasibility of usingmore » laser-based (CARS) daignostic instruments to make measurements in coal flames. The second task included improvements to the two-dimensional gasifier submodels, tabulation and evaluation of new coal devolatilization and char oxidation data for predictions, fundamental studies of turbulent particle dispersion, the development of improved numerical methods, and validation of the comprehensive model through comparison of predictions with experimental results. The third task was to transfer technical advances to industry and to METC through technical seminars, production of a detailed data book, code placement, and publication of results. Research results for these three tasks are summarized briefly here and presented in detail in the body of the report and in supporting references. 202 refs., 73 figs., 23 tabs.« less
2017-01-11
and to mitigate the defects in the coating that lead to damage under laser irradiation . In this final 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND...understand and to mitigate the defects in the coating that lead to damage under laser irradiation . In this final report we list the accomplishments of this...Luke A. Emmert, Wolfgang Rudolph. Time-dependent absorption of TiO_2 optical thin films under pulsed and continuous wave 790??nm laser irradiation
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-23
... DEPARTMENT OF EDUCATION Native American Career and Technical Education Program; Final Waivers and... American Career and Technical Education Program Catalog of Federal Domestic Assistance (CFDA) Number: 84.101A. SUMMARY: For 60-month projects funded in fiscal year (FY) 2007 under the Native American Career...
Center for Space Transportation and Applied Research Fifth Annual Technical Symposium Proceedings
NASA Technical Reports Server (NTRS)
1993-01-01
This Fifth Annual Technical Symposium, sponsored by the UT-Calspan Center for Space Transportation and Applied Research (CSTAR), is organized to provide an overview of the technical accomplishments of the Center's five Research and Technology focus areas during the past year. These areas include chemical propulsion, electric propulsion, commerical space transportation, computational methods, and laser materials processing. Papers in the area of artificial intelligence/expert systems are also presented.
48 CFR 1852.235-73 - Final Scientific and Technical Reports.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Final Scientific and Technical Reports. 1852.235-73 Section 1852.235-73 Federal Acquisition Regulations System NATIONAL..., including recommendations and conclusions based on the experience and results obtained. The final report...
Laser Powered Launch Vehicle Performance Analyses
NASA Technical Reports Server (NTRS)
Chen, Yen-Sen; Liu, Jiwen; Wang, Ten-See (Technical Monitor)
2001-01-01
The purpose of this study is to establish the technical ground for modeling the physics of laser powered pulse detonation phenomenon. Laser powered propulsion systems involve complex fluid dynamics, thermodynamics and radiative transfer processes. Successful predictions of the performance of laser powered launch vehicle concepts depend on the sophisticate models that reflects the underlying flow physics including the laser ray tracing the focusing, inverse Bremsstrahlung (IB) effects, finite-rate air chemistry, thermal non-equilibrium, plasma radiation and detonation wave propagation, etc. The proposed work will extend the base-line numerical model to an efficient design analysis tool. The proposed model is suitable for 3-D analysis using parallel computing methods.
NASA Astrophysics Data System (ADS)
Duff, Edward A.; Washburn, Donald C.
2004-09-01
Laser weapon systems would be significantly enhanced with the addition of high altitude or space-borne relay mirrors. Such mirrors, operating alone with a directed energy source, or many in a series fashion, can be shown to effectively move the laser source to the last, so-called fighting mirror. This "magically" reduces the range to target and offers to enhance the performance of directed energy systems like the Airborne Laser and even ground-based or ship-based lasers. Recent development of high altitude airships will be shown to provide stationary positions for such relay mirrors thereby enabling many new and important applications for laser weapons. The technical challenges to achieve this capability are discussed.
Chirped laser dispersion spectroscopy using a directly modulated quantum cascade laser
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hangauer, Andreas, E-mail: hangauer@princeton.edu; Nikodem, Michal; Wysocki, Gerard, E-mail: gwysocki@princeton.edu
2013-11-04
Chirped laser dispersion spectroscopy (CLaDS) utilizing direct modulation of a quantum cascade laser (QCL) is presented. By controlling the laser bias nearly single- and dual-sideband CLaDS operation can be realized in an extremely simplified optical setup with no external optical modulators. Capability of direct single-sideband modulation is a unique feature of QCLs that exhibit a low linewidth enhancement factor. The developed analytical model shows excellent agreement with the experimental, directly modulated CLaDS spectra. This method overcomes major technical limitations of mid-infrared CLaDS systems by allowing significantly higher modulation frequencies and eliminating optical fringes introduced by external modulators.
Laser Ablation for Cancer: Past, Present and Future
Schena, Emiliano; Saccomandi, Paola; Fong, Yuman
2017-01-01
Laser ablation (LA) is gaining acceptance for the treatment of tumors as an alternative to surgical resection. This paper reviews the use of lasers for ablative and surgical applications. Also reviewed are solutions aimed at improving LA outcomes: hyperthermal treatment planning tools and thermometric techniques during LA, used to guide the surgeon in the choice and adjustment of the optimal laser settings, and the potential use of nanoparticles to allow biologic selectivity of ablative treatments. Promising technical solutions and a better knowledge of laser-tissue interaction should allow LA to be used in a safe and effective manner as a cancer treatment. PMID:28613248
[Observation of carbon-bear free radicals using far infrared laser magnetic resonance spectroscopy].
Huang, Guang-ming; Shi, Li-hua; Cai, Xin; Liu, Yu-yan
2003-06-01
The principle and technical characters of far infrared laser magnetic resonance (FIRLMR) spectrometer built up in China are introduced. A CO2 transversely pumped far infrared laser is adopted. In order to obtain high sensitivity, the sample absorption cell is placed in the FIR laser cavity and separated from laser gain cavity with thin polypropylene film. The spectrometer can be employed to study short lived free radicals. The spectra of many transient free radicals including CCH, CF and CH2 have been detected by the spectrometer. These transients are generated by mixing CH4 with the fluorine atoms produced with microwave discharge.
Industrial laser welding evaluation study
NASA Technical Reports Server (NTRS)
Hella, R.; Locke, E.; Ream, S.
1974-01-01
High power laser welding was evaluated for fabricating space vehicle boosters. This evaluation was made for 1/4 in. and 1/2 in. aluminum (2219) and 1/4 in. and 1/2 in. D6AC steel. The Avco HPL 10 kW industrial laser was used to perform the evaluation. The objective has been achieved through the completion of the following technical tasks: (1) parameter study to optimize welding and material parameters; (2) preparation of welded panels for MSFC evaluation; and (3) demonstration of the repeatability of laser welding equipment. In addition, the design concept for a laser welding system capable of welding large space vehicle boosters has been developed.
Tao, Li; Zhu, Kun; Zhu, Jungao; Xu, Xiaohan; Lin, Chen; Ma, Wenjun; Lu, Haiyang; Zhao, Yanying; Lu, Yuanrong; Chen, Jia-Er; Yan, Xueqing
2017-07-07
With the development of laser technology, laser-driven proton acceleration provides a new method for proton tumor therapy. However, it has not been applied in practice because of the wide and decreasing energy spectrum of laser-accelerated proton beams. In this paper, we propose an analytical model to reconstruct the spread-out Bragg peak (SOBP) using laser-accelerated proton beams. Firstly, we present a modified weighting formula for protons of different energies. Secondly, a theoretical model for the reconstruction of SOBPs with laser-accelerated proton beams has been built. It can quickly calculate the number of laser shots needed for each energy interval of the laser-accelerated protons. Finally, we show the 2D reconstruction results of SOBPs for laser-accelerated proton beams and the ideal situation. The final results show that our analytical model can give an SOBP reconstruction scheme that can be used for actual tumor therapy.
1991-02-01
to adequately assess the health and environmental risks associated with the closure and transfer of the Annex forI other use; and 3) identification of...1990); Draft Final Technical Plan, Draft Final Sampling Design Plan and Draft Final Health and Safety Plan, USATHAMA, June 1990. 2.1.2 Draft Final...Final Technical Plan, Sampling Design Plan and Health and Safety Plan) supplied by USATHAMA. The estimate may be revised, with USATHAMA approval, as
Japanese aerospace science and technology 1992. A bibliography with indexes
NASA Technical Reports Server (NTRS)
1993-01-01
This report contains 4271 annotated references to reports and journal articles of Japaness intellectual origin entered into the NASA scientific and technical information system during 1992. Representative subject areas of interest include: adaptive control, antireflection coatings, fiber reinforced composites, gallium arsenide lasers, laser interferometry, reduced gravity (microgravity), and VHSIC (circuits).
Retrieval of the 1964 Laser Literature Using MIT's Project Tip.
ERIC Educational Resources Information Center
Keenan, Stella; Terry, Edward
Reported are the performance characteristics of the Massachusetts Institute of Technology Technical Information Program (TIP) system based on a study involving three search strategies in retrieval o f laser articles published in 1964. The TIP system provides access to (1) title, (2) author(s), (3) bibliographic references, and (4) literature…
The Potential Role of Drexon LaserCards in Optical Publishing.
ERIC Educational Resources Information Center
Schwerin, Julie B.
1985-01-01
Describes Drexon LaserCard (credit card size format holding two megabytes of digital data that can be recorded at factory or by information distributors) as a viable option to rotating optical media for distribution of computer software, technical manuals, periodicals, and other document applications, and projects its future in optical publishing.…
NASA Astrophysics Data System (ADS)
Wu, Zhibo; Zhang, Haifeng; Zhang, Zhongping; Deng, Huarong; Li, Pu; Meng, Wendong; Cheng, Zhien; Shen, Lurun; Tang, Zhenhong
2014-11-01
Laser ranging technology can directly measure the distance between space targets and ground stations with the highest measurement precision and will play an irreplaceable role in orbit check and calibrating microwave measurement system. The precise orbit determination and accurate catalogue of space targets can also be realized by laser ranging with multi-stations. Among space targets, most of ones are inactive targets and space debris, which should be paid the great attentions for the safety of active spacecrafts. Because of laser diffuse reflection from the surface of targets, laser ranging to space debris has the characteristics of wide coverage and weak strength of laser echoes, even though the powerful laser system is applied. In order to increase the receiving ability of laser echoes, the large aperture telescope should be adopted. As well known, some disadvantages for one set of large aperture telescope, technical development difficulty and system running and maintenance complexity, will limit its flexible applications. The multi-receiving telescopes technology in laser ranging to space targets is put forward to realize the equivalent receiving ability produced by one larger aperture telescope by way of using multi-receiving telescopes, with the advantages of flexibility and maintenance. The theoretical analysis of the feasibility and key technologies of multi-receiving telescopes technology in laser ranging to space targets are presented in this paper. The experimental measurement system based on the 60cm SLR system and 1.56m astronomical telescopes with a distance of about 50m is established to provide the platform for researching on the multi-receiving telescopes technology. The laser ranging experiments to satellites equipped with retro-reflectors are successfully performed by using the above experimental system and verify the technical feasibility to increase the ability of echo detection. And the multi-receiving telescopes technology will become a novel effective way to improve the detection ability of laser ranging to space debris.
Development of high-power CO2 lasers and laser material processing
NASA Astrophysics Data System (ADS)
Nath, Ashish K.; Choudhary, Praveen; Kumar, Manoj; Kaul, R.
2000-02-01
Scaling laws to determine the physical dimensions of the active medium and optical resonator parameters for designing convective cooled CO2 lasers have been established. High power CW CO2 lasers upto 5 kW output power and a high repetition rate TEA CO2 laser of 500 Hz and 500 W average power incorporated with a novel scheme for uniform UV pre- ionization have been developed for material processing applications. Technical viability of laser processing of several engineering components, for example laser surface hardening of fine teeth of files, laser welding of martensitic steel shroud and titanium alloy under-strap of turbine, laser cladding of Ni super-alloy with stellite for refurbishing turbine blades were established using these lasers. Laser alloying of pre-placed SiC coating on different types of aluminum alloy, commercially pure titanium and Ti-6Al-4V alloy, and laser curing of thermosetting powder coating have been also studied. Development of these lasers and results of some of the processing studies are briefly presented here.
UCSB FEL user-mode adaption project. Final report, 1 Jan 86-31 Dec 90
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jaccarino, V.
1992-04-14
This research sponsored by the SDIO Biomedical and Materials Sciences FEL Program held the following objectives. Provide a facility in which in-house and outside user research in the materials and biological sciences can be carried out in the Far Infrared using-the unique properties of the UCSB electrostatic accelerator-driven FEL. Develop and implement new FEL concepts and FIR technology and encourage the transfer and application of this research. Train graduate students, post doctoral researchers and technical personnel in varied aspects of scientific user disciplines, FEL science and FIR technology in a cooperative, interdisciplinary environment. In summary, a free electron laser facilitymore » has been developed which is operational from 200 GH z, (6.6 cm -1), to 4.8 THz, (160 cm-1) tunable under computer control and able to deliver kilowatts of millimeter wave and far-infrared power. This facility has a well equipped user lab that has been used to perform ground breaking experiments in scientific areas as diverse as bio-physics. Nine graduate students and post doctoral researchers have been trained in the operation, use and application of these free-electron lasers.« less
Industrial 2-kW TEA CO2 laser for paint stripping of aircraft
NASA Astrophysics Data System (ADS)
Schweizer, Gerhard; Werner, L.
1995-03-01
Paint stripping of aircraft with pulsed laser radiation has several advantages compared to traditional methods of depainting: selective removal of individual layers possible, suitable for sensitive surfaces, workpiece ready for immediate repainting, and considerable reduction of contaminated waste. For paint stripping of large aircraft pulsed lasers with average power of at least 2 kW are required. Amongst the various types of pulsed lasers technical and economical considerations clearly favor TEA CO2 lasers for this application. The first commercially available TEA CO2 laser with an average power in excess of 2 kW, especially designed for depainting, has been developed by Urenco. The key data of this laser are: pulse energy up to 9 J, repetition rate up to 330 Hz, and beam quality: `flat top'.
NASA Astrophysics Data System (ADS)
Wendt, Klaus; Gottwald, Tina; Hanstorp, Dag; Mattolat, Christoph; Raeder, Sebastian; Rothe, Sebastian; Schwellnus, Fabio; Havener, Charles; Lassen, Jens; Liu, Yuan
2010-02-01
Laser ion sources based on resonant excitation and ionization of atoms are well-established tools for selective and efficient production of radioactive ion beams. A recent trend is the complementary installation of reliable state-of-the-art all solid-state Ti:Sapphire laser systems. To date, 35 elements of the Periodic Table are available at laser ion sources by using these novel laser systems, which complements the overall accessibility to 54 elements including use of traditional dye lasers. Recent progress in the field concerns the identification of suitable optical excitation schemes for Ti:Sapphire laser excitation as well as technical developments of the source in respect to geometry, cavity material as well as by incorporation of an ion guide system in the form of the laser ion source trap LIST.
NASA Astrophysics Data System (ADS)
Zadkov, Victor N.; Koroteev, Nikolai I.
1995-10-01
An experience of managing the continuing education and retraining programs at the International Laser Center (ILC) of Moscow State University is discussed. The offered programs are in a wide range of areas, namely laser physics and technology, laser biophysics and biomedicine, laser chemistry, and computers in laser physics. The attendees who are presumably scientists, engineers, technical managers, and graduate students can join these programs through the annual ILC term (6 months), individual training and research programs (up to a year), annual ILC Laser Graduate School, graduate study, and post-docs program, which are reviewed in the paper. A curriculum that includes basic and specialized courses is described in detail. A brief description of the ILC Laser Teaching and Computer Labs that support all the educational courses is given as well.
Development of a low-cost multiple diode PIV laser for high-speed flow visualization
NASA Astrophysics Data System (ADS)
Bhakta, Raj; Hargather, Michael
2017-11-01
Particle imaging velocimetry (PIV) is an optical visualization technique that typically incorporates a single high-powered laser to illuminate seeded particles in a fluid flow. Standard PIV lasers are extremely costly and have low frequencies that severely limit its capability in high speed, time-resolved imaging. The development of a multiple diode laser system consisting of continuous lasers allows for flexible high-speed imaging with a wider range of test parameters. The developed laser system was fabricated with off-the-shelf parts for approximately 500. A series of experimental tests were conducted to compare the laser apparatus to a standard Nd:YAG double-pulsed PIV laser. Steady and unsteady flows were processed to compare the two systems and validate the accuracy of the multiple laser design. PIV results indicate good correlation between the two laser systems and verifies the construction of a precise laser instrument. The key technical obstacle to this approach was laser calibration and positioning which will be discussed. HDTRA1-14-1-0070.
Two Micron Laser Technology Advancements at NASA Langley Research Center
NASA Technical Reports Server (NTRS)
Singh, Upendra N.
2010-01-01
An Independent Laser Review Panel set up to examine NASA s space-based lidar missions and the technology readiness of lasers appropriate for space-based lidars indicated a critical need for an integrated research and development strategy to move laser transmitter technology from low technical readiness levels to the higher levels required for space missions. Based on the review, a multiyear Laser Risk Reduction Program (LRRP) was initiated by NASA in 2002 to develop technologies that ensure the successful development of the broad range of lidar missions envisioned by NASA. This presentation will provide an overview of the development of pulsed 2-micron solid-state laser technologies at NASA Langley Research Center for enabling space-based measurement of wind and carbon dioxide.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bulgakova, Nadezhda M., E-mail: nadezhda.bulgakova@hilase.cz; Institute of Thermophysics SB RAS, 1 Lavrentyev Ave., 630090 Novosibirsk; Zhukov, Vladimir P.
A comprehensive analysis of laser-induced modification of bulk glass by single ultrashort laser pulses is presented which is based on combination of optical Maxwell-based modeling with thermoelastoplastic simulations of post-irradiation behavior of matter. A controversial question on free electron density generated inside bulk glass by ultrashort laser pulses in modification regimes is addressed on energy balance grounds. Spatiotemporal dynamics of laser beam propagation in fused silica have been elucidated for the regimes used for direct laser writing in bulk glass. 3D thermoelastoplastic modeling of material relocation dynamics under laser-induced stresses has been performed up to the microsecond timescale when allmore » motions in the material decay. The final modification structure is found to be imprinted into material matrix already at sub-nanosecond timescale. Modeling results agree well with available experimental data on laser light transmission through the sample and the final modification structure.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-22
...: Final rule. SUMMARY: This final rule makes technical changes that will update a requirement that many of the written agreements and memoranda of understanding (MOUs) between the Food and Drug Administration.... This final rule, accordingly, eliminates it. We are making these technical changes to conserve Agency...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-23
... DEPARTMENT OF EDUCATION Native Hawaiian Career and Technical Education Program; Final Waiver and.... ACTION: Notice. Overview Information Final Waiver and Extension of Project Period for the Native Hawaiian.... SUMMARY: For 36-month projects funded in fiscal year (FY) 2009 under the Native Hawaiian Career and...
High precision, rapid laser hole drilling
Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.
2007-03-20
A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.
High precision, rapid laser hole drilling
Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.
2005-03-08
A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.
High precision, rapid laser hole drilling
Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.
2013-04-02
A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.
Low-Tech Laser Learning: Can Less Be More?
ERIC Educational Resources Information Center
Tatsuki, Donna Hurst
1997-01-01
Examines an alternative to high-powered, high-tech use of laser disk technology in teaching English as a Second Language. Points out that there has not been a rush to install this technology because of cost, scarcity of courseware, incompatibility of the various delivery systems and the time investment/technical expertise required of the teacher.…
Unstable Resonator Mid-Infrared Laser Sources
2016-02-26
of individual materials depending on metal species and growth temperatures . Fig. 8 (a) Average power consumption and (b) delay of C2MOS and double...feedback lasers, chirped gratings, interferometric lithography, nanowire transistors, tunnel field- effect transistors, nanoscale epitaxial growth, nanowire...technical approaches. Approaches to wavelength tuning include thermal/operation temperature tuning [1], variable cavity length with cantilever/piezo
The modern trends of the evolution laser information technology in oncology
NASA Astrophysics Data System (ADS)
Mikov, A. A.; Svirin, V. N.
2008-04-01
Laser-optical information technologies and devices develop since the 70- years at the end of 20 century and are broadly used for diagnostics and treatment of oncological diseases to date. Although such methods as photodynamic therapy (PDT), laser-induce thermotherapy (LITT), fluorescent diagnostics and spectrophotometry already more than 30 years are used for treatment and diagnostics of oncological diseases, nevertheless, they are enough new methods and, as a rule, are used in large scientific centers and medical institutions. This is bound, first of all, with lack of information on modern method of cancer treatment, the absence of widely available laser procedures and corresponding devices in the polyclinics and even in district hospitals, as well as insufficient understanding of application areas, where laser methods has an advantage by comparison, for instance, with beam or chemotherapy. At present day laser methods are fast upcoming direction of the treatment oncological diseases. This is explained by progress in development essentially laser, particularly diode, improvement electronic and computing components and broad introduction software-algorithmic methods of control the undertaking therapeutic and diagnostic procedures. In article are considered new laser methods of the undertaking diagnostic and therapeutic procedures and is shown that introduction multiwave laser radiation for probe and influences on tissue, the different methods of the determination of the functional state of tissues, realization of the on-line diagnostics when carrying out the therapeutic procedures, automatic control systems of the power laser radiation, which depends on state patient tissue, as well as software-algorithmic methods of management session therapeutic and diagnostic procedures greatly raises efficiency of the treatment oncological diseases. On an example of the multipurpose laser therapeutic devices("MLTA") developed and introduced in clinical practice and multipurpose laser diagnostic complexes ("MLDC"), the realizing offered methods, are shown the basic tendencies of development laser methods in oncology, concrete technical decisions and the experimental clinical material showing increase of efficiency of treatment of a cancer at their realization are resulted. It is shown, that realization of the offered methods and technical technologies opens new competitive advantages laser technologies in comparison with beam and chemical-therapy at treatment of oncological diseases.
1987-10-31
measurement. A cube beam splitter divided incident laser light, I, into two beams , IR and I0, of approximately equal intensity. The reference laser...scattered molecules were found to be strongly dependent on beam kinetic energy. These distributions are markedly non -Boltzmann and indicate that the...satisfy these requirements has been developed. The system, named OBIR for optical beam induced reflectance, is non -destructive and operates at 20C in
NASA Astrophysics Data System (ADS)
Mallets, T.
1983-12-01
The Laser Paint Stripper program is a three phase effort which includes: feasibility demonstration; prototype optimization; and implementation at our Air Logistic Centers (depots) by FY88. Major technical areas that make up the automated system include: (1) laser device with power and uptime to handle the number and size of aircraft (F-16 vs C-5A); (2) the beam transport and manipulation system; (3) controls for beam/aircraft safety, alignment, and surface condition sensors; (4) integration software; and (5) cleanup of residue products.
Bioengineering assessment of acupuncture, part 8: innovative moxibustion.
Litscher, Gerhard
2010-01-01
The actual Chinese character for acupuncture, translated literally, means "acupuncture-moxibustion." This shows the enormous importance of moxibustion in Asia for thousands of years. In this review article, the history of the burning of mugwort (moxatherapy) is briefly described. In addition, new technical methods such as new infrared-moxa or laser-moxa devices, electrobian stone moxibustion, and the investigations of a new needle-moxa system using high-tech methods such as thermography, laser Doppler flowmetry, and laser Doppler imaging are presented.
Measurement of Fluorine Atom Concentrations and Reaction Rates in Chemical Laser Systems.
1981-09-01
AD-A1RA 070 AERODYNEERESEARCHUINC BEDFORDM MA F/6_20/5 MEASURE MENT OF FLUORINE ATOM CONCENTRATIONS AND REACTION RATFS -ETC(U) SEP_ A A C STANT ON...0772 LEVELIg 00 ~ARI-RR-272 cO0 MEASUREMENT OF FLUORINE ATOM CONCENTRATIONS AND REACTION RATES IN CHEMICAL LASER SYSTEMS ANNUAL TECHNICAL REPORT by...MEASUREMENT OF FLUORINE ATOM CONCENTRATIONS AND Annual Report REACTION RATES IN CHEMICAL LASER SYSTEMS 23 July 1980 - 23 July 1981 S. PERFORMING ORG. REPORT
JPRS Report, Soviet Union, Foreign Military Review, No. 5, May 1987
1987-09-18
which can carry up to 16 Hellfire missiles with semi-active laser homing devices (maximum range of 6,000 m). The presence of good flight and technical...will have laser -guided control systems, that is, will retain the link between the missile and the launch installation right up to impact on target as...antitank missile system to replace the Milan system in the 1990s. The control system with a laser -guided homing device also has been accepted for
Nd:YAG development for spaceborne laser ranging system
NASA Technical Reports Server (NTRS)
Harper, L. L.; Logan, K. E.; Williams, R. H.; Stevens, D. A.
1979-01-01
The results of the development of a unique modelocked laser device to be utilized in future NASA space-based, ultraprecision laser ranger systems are summarized. The engineering breadboard constructed proved the feasibility of the pump-pulsed, actively modelocked, PTM Q-switched Nd:YAG laser concept for the generation of subnanosecond pulses suitable for ultra-precision ranging. The laser breadboard also included a double-pass Nd:YAG amplifier and provision for a Type II KD*P frequency doubler. The specific technical accomplishment was the generation of single 150 psec, 20-mJ pulses at 10 pps at a wavelength of 1.064 micrometers with 25 dB suppression of pre-and post-pulses.
NASA Astrophysics Data System (ADS)
Hall, John L.
2010-02-01
Michelson's 1907 proposal to define the SI Metre in terms of an optical wavelength was realized only in 1960, based on a ^86Krypton discharge lamp. The same year saw the cw HeNe laser arrive and a future redefinition based on laser technology assured. Separation in the late 60's of the laser's gain and spectral-reference-gas functions led to unprecedented levels of laser frequency stability and reproducibility. In addition to HeNe:CH4 system at 3392 nm and HeNe:I2 at 633 nm, systems at 514 nm and 10600 nm were studied. Absolute frequency measurement became the holy grail and some NBS team experiences will be shared. We measured both frequency and wavelength in 1972, and so obtained a speed of light value, improved 100-fold in accuracy. During the next decade, the NBS value of c was confirmed by other national labs, and frequency metrology was extended to the 473 THz (633 nm) Iodine-based wavelength standard. This frequency to ˜10 digit accuracy was obtained in 1983, thus setting the stage for redefining the SI Metre. By consensus choice the value 299 792 458 m/s was adopted for the speed of light, effectively reducing the Metre to a derived SI quantity. Knowledge of the frequency of the particular laser being utilized was controlled by International intercomparisons, but the need for a fast and accurate means to make these laser frequency measurements was obvious. Creative proposals by H"ansch and by Chebotayev were to use ultra-fast repetitive pulses to create an ``Optical Comb,'' but it was years before any technical basis existed to implement their Fourier dreams. Finally, in 1999 the last needed capability was demonstrated -- continuum production at 100 MHz rates and non-destructive power levels. By May 2000 phase-locked combs were operational in both Garching and Boulder, substantially accelerated by their collaborative interactions. Within 18 months all the known proposed ``optical frequency standards'' had been accurately measured via Comb techniques. )
NASA Astrophysics Data System (ADS)
Dixit, S. K.
The field of gas lasers, started with the invention of He-Ne laser in 1961, has witnessed tremendous growth in terms of technology development, research into gaseous gain medium, resonator physics and application in widely diverse arenas. This was possible due to high versatility of gas lasers in terms of operating wavelengths, power, beam quality and mode of operation. In recent years, there is a definite trend to replace the gas lasers, wherever possible, by more efficient and compact solid-state lasers. However, for many industrial, medical and military applications, the gas lasers still rule the roost due to their high-power capabilities with good beam quality at specific wavelengths. This chapter presents a short review covering the operating principle, important technical details and application potential of all the important gas lasers such as He-Ne, CO2, argon ion, copper vapour, excimer and chemical lasers. These neutral atoms, ions and molecule gas lasers are discussed as per applicable electrical, chemical and optical excitation schemes. The optically pumped gas lasers, recently experiencing resurgence, are discussed in the context of far infrared THz molecular lasers, diode-pumped alkali lasers and optically pumped gas-filled hollow-core fibre lasers.
2005 v4.3 Technical Support Document
Emissions Modeling for the Final Mercury and Air Toxics Standards Technical Support Document describes how updated 2005 NEI, version 2 emissions were processed for air quality modeling in support of the final Mercury and Air Toxics Standards (MATS).
High-power CO laser with RF discharge for isotope separation employing condensation repression
NASA Astrophysics Data System (ADS)
Baranov, I. Ya.; Koptev, A. V.
2008-10-01
High-power CO laser can be the effective tool in such applications as isotope separation using the free-jet CRISLA method. The way of transfer from CO small-scale experimental installation to industrial high-power CO lasers is proposed through the use of a low-current radio-frequency (RF) electric discharge in a supersonic stream without an electron gun. The calculation model of scaling CO laser with RF discharge in supersonic stream was developed. The developed model allows to calculate parameters of laser installation and optimize them with the purpose of reception of high efficiency and low cost of installation as a whole. The technical decision of industrial CO laser for isotope separation employing condensation repression is considered. The estimated cost of laser is some hundred thousand dollars USA and small sizes of laser head give possibility to install it in any place.
Molecular laser stabilization for LISA
NASA Astrophysics Data System (ADS)
Halloin, Hubert; Acef, Ouali; Argence, Berengere; Jeannin, Olivier; Prat, Pierre; de Vismes, Eden; Plagnol, Eric; Brillet, Alain; Mondin, Linda; Berthon, Jacques; Turazza, Oscar
2017-11-01
The expected performance of LISA relies on two main technical challenges: the ability for the spacecrafts to precisely follow the free-flying masses and the outstanding precision of the phase shift measurement. This latter constraint requires frequency stabilized lasers and efficient numerical algorithms to account for the redundant, delayed noise propagation, thus cancelling laser phase noise by many orders of magnitude (TDI methods). Recently involved in the technical developments for LISA, the goal of our team at APC (France) is to contribute on these two subjects: frequency reference for laser stabilization and benchtop simulation of the interferometer. In the present design of LISA, two stages of laser stabilization are used (not accounting for the "post-processed" TDI algorithm): laser pre-stabilization on a frequency reference and lock on the ultra stable distance between spacecrafts (arm-locking). While the foreseen (and deeply studied) laser reference consists of a Fabry-Perot cavity, other techniques may be suitable for LISA or future metrology missions. In particular, locking to a molecular reference (namely iodine in the case of the LISA Nd:YAG laser) is an interesting alternative. It offers the required performance with very good long-term stability (absolute frequency reference) though the reference can be slightly tuned to account for arm-locking. This technique is currently being investigated by our team and optimized for LISA (compactness, vacuum compatibility, ease of use and initialization, etc.). A collaboration with a French laboratory (the SYRTE) had been started aiming to study a second improved technique consisting in inserting the iodine cell in a Fabry-Perot cavity. Ongoing results and prospects to increase the performance of the system are presented in the present article.
Evaluation of IMS - Swedish Laser road tester : final report.
DOT National Transportation Integrated Search
1990-09-01
A test of the IMS - Swedish Laser road tester was conducted in September 1988. The vehicle mounted laser equipment was used to survey pavement conditions on sections of Oregon's Interstate and non-interstate highway system. : The IMS laser equipment ...
The Center for Space Telemetering and Telecommunications Systems
NASA Technical Reports Server (NTRS)
Horan, S.; DeLeon, P.; Borah, D.; Lyman, R.
2003-01-01
This report comprises the final technical report for the research grant 'Center for Space Telemetering and Telecommunications Systems' sponsored by the National Aeronautics and Space Administration's Goddard Space Flight Center. The grant activities are broken down into the following technology areas: (1) Space Protocol Testing; (2) Autonomous Reconfiguration of Ground Station Receivers; (3) Satellite Cluster Communications; and (4) Bandwidth Efficient Modulation. The grant activity produced a number of technical reports and papers that were communicated to NASA as they were generated. This final report contains the final summary papers or final technical report conclusions for each of the project areas. Additionally, the grant supported students who made progress towards their degrees while working on the research.
The sound of dental tissue ablation as a possible parameter for conservative dentistry
NASA Astrophysics Data System (ADS)
Robles, Fábio Renato P.; Mendes, Fausto Medeiros; Matos, Adriana Bona
2007-02-01
Studies in cariology have been struggling for the development of caries prevention techniques, precocious diagnoses of lesions, re-mineralization of incipient carious lesions and early restorative intervention with minimally invasive procedures. When removing caries, healthy dental structure is often removed inadvertently during its final phase, for being quite difficult to precise the limits between viable and decayed dental tissues clinically. With laser technologies, a subjective clinical hint, often used to indicate when tissue ablation should be stopped is that different sounds are perceptive whether in carious (bass) or in healthy (treble) dental structure; when sound produced by ablation turned treble it would mean that healthy tissue was reached. This study aims to classify those audio differences and to turn them into objective parameters for a conservative operative dentistry with minimally invasive tissue removal when using erbium lasers. Twenty freshly extracted human teeth were used (10 decayed and 10 sound teeth). Dentine was erbium laser irradiated under same parameters, distance and refrigeration and a mono directional microphone was set 10 cm far from the operative area in order to capture and record the ablation produced sounds when working either on carious or healthy dentine. Ten pulses per file were then analysed in a computer software (200 analyses). It was permitted to draw similarities among the patterns in each group (decayed and healthy teeth) as well as differences between decayed and healthy produced sounds. Audio analysis came out to be a technical reliable objective parameter to determine whether laser ablated dentine substrates are decayed or sound; therefore it can be proposed as a conservative parameter, avoiding unnecessary removal of healthy dentine and restricting it to carious one.
Laser Research and Development Studies for Laser Guide Star Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pennington, D.; Beach, R.; Ebbers, C.
2000-02-23
In this paper we consider two CW solid state laser approaches to a 589 nm LGS system. Both are based on the technique of sum-frequency generation, but differ in the cavity architecture. Both technologies are very promising and are worth of further consideration. This preliminary proposal is intended to encompass both designs. A down select shall be performed early in the project execution to focus on the most promising option. The two design options consist of: (1) A dual-frequency resonator with intra-cavity doubling in LB0 offers the promise of a simple architecture and may scale more easily to high power.more » This design has been shown to be highly reliable, efficient and high power when used in frequency-doubled Nd:YAG lasers for programs at LLNL and in commercial products. The challenge in this design is the demonstration of a high power13 18 nm oscillator with adequate suppression of the 1064 nm line. (2) A MOPA based design uses commercial low power oscillators to produce both wavelengths, then amplifies the wavelengths before doubling. This design requires the demonstration of a 1318 nm amplifier, though the design is scaled from a kW CW amplifier already delivered to a customer at a different wavelength. The design must also demonstrate high power scaling of sum-frequency generation in the relatively new nonlinear material, PPLN. The first step in the process would be to further evaluate the two conceptual options for technical feasibility, cost and constructability. Then a down selection to one design would be conducted. Finally, R&D on that design would then proceed. Minimal testing should be required for this selection. The majority of the funding received would be allocated to development of the design selected.« less
Control of active reflector system for radio telescope
NASA Astrophysics Data System (ADS)
Zhou, Guo-hua; Li, Guo-ping; Zhang, Yong; Zhang, Zhen-chao
2016-10-01
According to the control requirements of the active reflector surface in the 110 m radio telescope at QiTai(QTT) Xinjiang, a new displacement actuator and a new displacement control system were designed and manufactured and then their characteristics were tested by a dual-frequency laser interferometer in the micro-displacement laboratory. The displacement actuator was designed by a scheme of high precision worm and roller screw structures, and the displacement control system was based on a ARM micro-processor. Finally, the S curve acceleration control methods were used to design the hardware platform and software algorithm for the active reflection surface of the control system. The test experiments were performed based on the laser metrology system on an active reflector close-loop antenna prototype for large radio telescope. Experimental results indicate that it achieves a 30 mm working stroke and 5 μm RMS motion resolution. The accuracy (standard deviation) is 3.67 mm, and the error between the determined and theoretical values is 0.04% when the rated load is 300 kg, the step is 2 mm and the stroke is 30mm. Furthermore, the active reflector integrated system was tested by the laser sensors with the accuracy of 0.25 μm RMS on 4-panel radio telescope prototype, the measurement results show that the integrated precision of the active reflector closed-loop control system is less than 5 μm RMS, and well satisfies the technical requirements of active reflector control system of the QTT radio telescope in 3 mm wavelength.
ERIC Educational Resources Information Center
United Nations Educational, Scientific, and Cultural Organization, Paris (France).
This monograph includes the final report of the International Expert Meeting on the Promotion of Equal Access of Girls and Women to Technical and Vocational Education (TVE) held in Seoul, Republic of Korea, and country discussion papers. The final report is composed of an introduction that proposes that many Member States require special measures…
Air Quality Modeling Technical Support Document for the Final Cross State Air Pollution Rule Update
In this technical support document (TSD) we describe the air quality modeling performed to support the final Cross State Air Pollution Rule for the 2008 ozone National Ambient Air Quality Standards (NAAQS).
7 CFR 614.7 - Preliminary technical determinations.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 6 2010-01-01 2010-01-01 false Preliminary technical determinations. 614.7 Section... Preliminary technical determinations. (a) A preliminary technical determination becomes final 30 days after... purpose of gathering additional information and discussing the facts relating to the preliminary technical...
Electro-Optical Laser Technology. Curriculum Utilization. Final Report.
ERIC Educational Resources Information Center
Nawn, John H.
This report describes a program to prepare students for employment as laser technicians and laser operators and to ensure that they have the necessary skills required by the industry. The objectives are to prepare a curriculum and syllabus for an associate degree program in Electro-Optical Laser Technology. The 2-year Electro-Optical Laser program…
Automatic laser welding and milling with in situ inline coherent imaging.
Webster, P J L; Wright, L G; Ji, Y; Galbraith, C M; Kinross, A W; Van Vlack, C; Fraser, J M
2014-11-01
Although new affordable high-power laser technologies enable many processing applications in science and industry, depth control remains a serious technical challenge. In this Letter we show that inline coherent imaging (ICI), with line rates up to 312 kHz and microsecond-duration capture times, is capable of directly measuring laser penetration depth, in a process as violent as kW-class keyhole welding. We exploit ICI's high speed, high dynamic range, and robustness to interference from other optical sources to achieve automatic, adaptive control of laser welding, as well as ablation, achieving 3D micron-scale sculpting in vastly different heterogeneous biological materials.
Wen, Daizong; Huang, Jinhai; Li, Xuexi; Savini, Giacomo; Feng, Yifan; Lin, Qiaoya; Wang, Qinmei
2014-01-01
To identify possible differences between laser-assisted subepithelial keratectomy and epipolis laser in situ keratomileusis for myopia. Meta-analysis. Patients from previously reported comparative studies treated by laser-assisted subepithelial keratectomy versus epipolis laser in situ keratomileusis. A systematic literature retrieval was conducted in the MEDLINE, EMBASE and Cochrane Library, up to January 2013. The included studies were subject to a meta-analysis using a RevMan 5.1 version software. The differences in efficacy, predictability, safety, epithelial healing time, pain perception and corneal haze formation. A total of six studies involving 517 eyes were included. There were no statistically significant differences in the final proportion of eyes with uncorrected visual acuity of 6/6 or better (P = 0.43), mean postoperative uncorrected visual acuity (P = 0.53), final proportion of eyes with refraction within ± 0.50 D (P = 0.62) and ± 1.00 D (P = 0.16) of target, final proportion of eyes losing two or more lines of best spectacle-corrected visual acuity (P = 1.00), healing time of corneal epithelium (P = 0.58), final proportion of eyes with corneal haze grade 0.5 or higher (P = 0.26), and corneal haze levels (P = 0.36). There were no significant differences in efficacy, predictability, safety, epithelial healing time and corneal haze formation between laser-assisted subepithelial keratectomy and epipolis laser in situ keratomileusis, but the result was limited. Future more data are required to detect the potential differences between the two procedures. © 2013 Royal Australian and New Zealand College of Ophthalmologists.
ERIC Educational Resources Information Center
Hammond, Cathy; Drew, Sam F.; Withington, Cairen; Griffith, Cathy; Swiger, Caroline M.; Mobley, Catherine; Sharp, Julia L.; Stringfield, Samuel C.; Stipanovic, Natalie; Daugherty, Lindsay
2013-01-01
This is the final technical report from the National Research Center for Career and Technical Education's (NRCCTE's) five-year longitudinal study of South Carolina's Personal Pathway to Success initiative, which was authorized by the state's Education and Economic Development Act (EEDA) in 2005. NRCCTE-affiliated researchers at the National…
Adaptive Optics for the Thirty Meter Telescope
NASA Astrophysics Data System (ADS)
Ellerbroek, Brent
2013-12-01
This paper provides an overview of the progress made since the last AO4ELT conference towards developing the first-light AO architecture for the Thirty Meter Telescope (TMT). The Preliminary Design of the facility AO system NFIRAOS has been concluded by the Herzberg Institute of Astrophysics. Work on the client Infrared Imaging Spectrograph (IRIS) has progressed in parallel, including a successful Conceptual Design Review and prototyping of On-Instrument WFS (OIWFS) hardware. Progress on the design for the Laser Guide Star Facility (LGSF) continues at the Institute of Optics and Electronics in Chengdu, China, including the final acceptance of the Conceptual Design and modest revisions for the updated TMT telescope structure. Design and prototyping activities continue for lasers, wavefront sensing detectors, detector readout electronics, real-time control (RTC) processors, and deformable mirrors (DMs) with their associated drive electronics. Highlights include development of a prototype sum frequency guide star laser at the Technical Institute of Physics and Chemistry (Beijing); fabrication/test of prototype natural- and laser-guide star wavefront sensor CCDs for NFIRAOS by MIT Lincoln Laboratory and W.M. Keck Observatory; a trade study of RTC control algorithms and processors, with prototyping of GPU and FPGA architectures by TMT and the Dominion Radio Astrophysical Observatory; and fabrication/test of a 6x60 actuator DM prototype by CILAS. Work with the University of British Columbia LIDAR is continuing, in collaboration with ESO, to measure the spatial/temporal variability of the sodium layer and characterize the sodium coupling efficiency of several guide star laser systems. AO performance budgets have been further detailed. Modeling topics receiving particular attention include performance vs. computational cost tradeoffs for RTC algorithms; optimizing performance of the tip/tilt, plate scale, and sodium focus tracking loops controlled by the NGS on-instrument wavefront sensors, sky coverage, PSF reconstruction for LGS MCAO, and precision astrometry for the galactic center and other observations.
Direct Final Rule: Nonroad Diesel Technical Amendments and Tier 3 Technical Relief Provision
Rule making certain technical corrections to the rules establishing emission standards for nonroad diesel engines and amending those rules to provide manufacturers with a production technical relief provision for Tier 3 equipment.
NASA Astrophysics Data System (ADS)
Azrina Talik, Noor; Boon Kar, Yap; Noradhlia Mohamad Tukijan, Siti; Wong, Chuan Ling
2017-10-01
To date, the state of art organic semiconductor distributed feedback (DFB) lasers gains tremendous interest in the organic device industry. This paper presents a short reviews on the fabrication techniques of DFB based laser by focusing on the fabrication method of DFB corrugated structure and the deposition of organic gain on the nano-patterned DFB resonator. The fabrication techniques such as Laser Direct Writing (LDW), ultrafast photo excitation dynamics, Laser Interference Lithography (LIL) and Nanoimprint Lithography (NIL) for DFB patterning are presented. In addition to that, the method for gain medium deposition method is also discussed. The technical procedures of the stated fabrication techniques are summarized together with their benefits and comparisons to the traditional fabrication techniques.
PHARAO space atomic clock: new developments on the laser source
NASA Astrophysics Data System (ADS)
Saccoccio, Muriel; Loesel, Jacques; Coatantiec, Claude; Simon, Eric; Laurent, Philippe; Lemonde, Pierre; Maksimovic, I.; Abgrall, M.
2017-11-01
The PHARAO project purpose is to open the way for a new atomic clock generation in space, where laser cooling techniques and microgravity allow high frequency stability and accuracy. The French space agency, CNES is funding and managing the clock construction. The French SYRTE and LKB laboratories are scientific and technical advisers for the clock requirements and the follow-up of subsystem development in industrial companies. EADS SODERN is developing two main subsystems of the PHARAO clock: the Laser Source and the Cesium Tube where atoms are cooled, launched, selected and detected by laser beams. The Laser Source includes an optical bench and electronic devices to generate the laser beams required. This paper describes PHARAO and the role laser beams play in its principle of operation. Then we present the Laser Source design, the technologies involved, and the status of development. Lastly, we focus of a key equipment to reach the performances expected, which is the Extended Cavity Laser Diode.
Distributed ultrafast fibre laser
Liu, Xueming; Cui, Yudong; Han, Dongdong; Yao, Xiankun; Sun, Zhipei
2015-01-01
A traditional ultrafast fibre laser has a constant cavity length that is independent of the pulse wavelength. The investigation of distributed ultrafast (DUF) lasers is conceptually and technically challenging and of great interest because the laser cavity length and fundamental cavity frequency are changeable based on the wavelength. Here, we propose and demonstrate a DUF fibre laser based on a linearly chirped fibre Bragg grating, where the total cavity length is linearly changeable as a function of the pulse wavelength. The spectral sidebands in DUF lasers are enhanced greatly, including the continuous-wave (CW) and pulse components. We observe that all sidebands of the pulse experience the same round-trip time although they have different round-trip distances and refractive indices. The pulse-shaping of the DUF laser is dominated by the dissipative processes in addition to the phase modulations, which makes our ultrafast laser simple and stable. This laser provides a simple, stable, low-cost, ultrafast-pulsed source with controllable and changeable cavity frequency. PMID:25765454
Dynamics of Superradiant Lasers
NASA Astrophysics Data System (ADS)
Thompson, James
2014-05-01
A superradiant laser has been shown to operate with less than one photon on average inside of the optical cavity. In this regime, almost all of the phase information of the laser is stored in the atoms rather than the cavity field. As a result, the laser's phase is highly insensitive to both technical and fundamental thermal cavity mirror vibrations. This vibration noise presently limits the coherence of the best lasers as well as the precision of the optical lattice clocks that these lasers interrogate. We have explored the physics of superradiant lasers utilizing Raman transitions between hyperfine states in rubidium to mimic narrow optical transitions. In this talk, we will discuss the amplitude stability of our superradiant Raman laser, and the dynamics of phase synchronization in our system. We will also consider the prospects for future superradiant lasers that would lase on the same highly-forbidden transitions used in optical lattice clocks. We acknowledge support from DARPA QUASAR, ARO, NIST, and the NSF PFC.
Advances in bone surgery: the Er:YAG laser in oral surgery and implant dentistry
Stübinger, Stefan
2010-01-01
The erbium-doped yttrium aluminium garnet (Er:YAG) laser has emerged as a possible alternative to conventional methods of bone ablation because of its wavelength of 2.94 μm, which coincides with the absorption peak of water. Over the last decades in several experimental and clinical studies, the widespread initial assumption that light amplification for stimulated emission of radiation (laser) osteotomy inevitably provokes profound tissue damage and delayed wound healing has been refuted. In addition, the supposed disadvantage of prolonged osteotomy times could be overcome by modern short-pulsed Er:YAG laser systems. Currently, the limiting factors for a routine application of lasers for bone ablation are mainly technical drawbacks such as missing depth control and a difficult and safe guidance of the laser beam. This article gives a short overview of the development process and current possibilities of noncontact Er:YAG laser osteotomy in oral and implant surgery. PMID:23662082
Laser Drilling Development Trial Final Report CRADA No. TSB-1538-98
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hermann, M. R.; Hebbar, R. R.
This project performed various laser drilling tests to demonstrate femtosecond laser drilling of fuel injector nozzles with minimal recast, minimal heat affected zone and no collateral damage. LLNL had extensive experience in ultra short-pulse laser systems and developed specialized hardware for these applications.
DARPA-NRL Laser Program Annual Technical Report to Defense Advanced Research Projects Agency
1980-04-30
sorption could be removed or significantly reduced then the output power and efficiency of the XeCl laser could be further improved. Figure 1 plots...to 30 nm closer to the visible than the experimentally observed ab- sorption peak for Xe2+ (Fig. 3). Figure 3 is a plot of the measured absorption in...radiation in o00 argon-xenon and neon-xenon mixtures. A reduction in ab- No:X: HCt 41. sorption at the laser wavelength was observed when small r’ NEN
Laser mass spectrometry of chemical warfare agents using ultrashort laser pulses
NASA Astrophysics Data System (ADS)
Weickhardt, C.; Grun, C.; Grotemeyer, J.
1998-12-01
Fast relaxation processes in excited molecules such as IC, ISC, and fragmentation are observed in many environmentally and technically relevant substances. They cause severe problems to resonance ionization mass spectrometry because they reduce the ionization yield and lead to mass spectra which do not allow the identification of the compound. By the use of ultrashort laser pulses these problems can be overcome and the advantages of REMPI over conventional ionization techniques in mass spectrometry can be regained. This is demonstrated using soil samples contaminated with a chemical warfare agent.
1975-03-01
10 J. The beam divergence was 8 mrad. A beam splitter and an S-l response photodlode were used to monitor the laser pulse signal shape and the...laser beams on a cylinder [231] to compress a material to the necessary inversion density will be plagued by the non -uniform gain that these focused...of 30 psec and a good beam divergence can emerge after the non -linear stages as a 1773, 1182, or 887 k pulse still possessing good beam quality
Rewriting magnetic phase change memory by laser heating
NASA Astrophysics Data System (ADS)
Timmerwilke, John; Liou, Sy-Hwang; Cheng, Shu Fan; Edelstein, Alan S.
2016-04-01
Magnetic phase change memory (MAG PCM) consists of bits with different magnetic permeability values. The bits are read by measuring their effect on a magnetic probe field. Previously low permeability crystalline bits had been written in high permeability amorphous films of Metglas via laser heating. Here data is presented showing that by applying short laser pulses with the appropriate power to previously crystallized regions they can first be vitrified and then again crystallized. Thus, MAG PCM is rewriteable. Technical issues in processing the bits are discussed and results on thermal modeling are presented.
NASA Technical Reports Server (NTRS)
Kalil, Ford
1990-01-01
NASA is considering the use of various airplanes for a Shuttle Laser Technology Experiment Facility (LTEF)-to-Airplane laser communications experiment. As supporting documentation, pertinent technical details are included about the potential use of airplanes located at Ames Research Center and Wallops Flight Facility. The effects and application of orbital mechanics considerations are also presented, including slant range, azimuth, elevation, and time. The pros and cons of an airplane equipped with a side port with a bubble window versus a top port with a dome are discussed.
Diode laser supported partial nephrectomy in laparoscopic surgery: preliminary results
NASA Astrophysics Data System (ADS)
Sroka, Ronald; Hennig, Georg; Zillinberg, Katja; Khoder, Wael Y.
2011-07-01
Introduction: Warm ischemia and bleeding during laparoscopic partial nephrectomy place technical constraints on surgeons. Therefore it was the aim to develop a safe and effective laser assisted partial nephrectomy technique without need for ischemia. Patients and methods: A diode laser emitting light at 1318nm in cw mode was coupled into a bare fibre (core diameter 600 μm) thus able to transfer up to 100W to the tissue. After dry lab experience, a total of 8 patients suffering from kidney malformations underwent laparoscopic/retroperitoneoscopic partial nephrectomy. Clinically, postoperative renal function and serum c-reactive protein (CRP) were monitored. Laser induced coagulation depth and effects on resection margins were evaluated. Demographic, clinical and follow-up data are presented. Results: Overall interventions, the mean operative time was 116,5 minutes (range 60-175min) with mean blood loss of 238ml (range 50-600ml) while laser assisted resection of the kidney tissue took max 15min. After extirpation of the tumours all patients showed clinical favourable outcome during follow up period. The tumour size was measured to be 1.8 to 5cm. With respect to clinical safety and due to blood loos, two warm ischemia (19 and 24min) must be performed. Immediate postoperative serum creatinine and CRP were elevated within 0.1 to 0.6 mg/dl (mean 0.18 mg/dl) and 2.1-10 mg/dl (mean 6.24 mg/dl), respectively. The depth of the coagulation on the removed tissue ranged between <1 to 2mm without effect on histopathological evaluation of tumours or resection margin. As the surface of the remaining kidney surface was laser assisted coagulated after removal. The sealing of the surface was induced by a slightly larger coagulation margin, but could not measured so far. Conclusion: This prospective in-vivo feasibility study shows that 1318nm-diode laser assisted partial nephrectomy seems to be a safe and promising medical technique which could be provided either during open surgery as well as laparascopically. This application showed good haemostasis and minimal parenchymal damage. Oncological safety appears to be warranted by the use of diode laser. Further investigations and development are needed for on-line detection of the remain coagulation margin, optimisation of the treatment equipment, and finally to train the application technique.
Arizona Deafblind Project, 1995-1999. Final Report.
ERIC Educational Resources Information Center
Arizona State School for the Deaf and Blind, Tucson.
This final report describes accomplishments of the four-year federally funded Arizona Deafblind Project which attempted to: (1) identify all deafblind children in Arizona; (2) deliver technical assistance to families; (3) deliver technical assistance to service providers; and (4) enhance community oversight, coordination, and collaboration with…
One-dimensional CdS nanostructures: a promising candidate for optoelectronics.
Li, Huiqiao; Wang, Xi; Xu, Junqi; Zhang, Qi; Bando, Yoshio; Golberg, Dmitri; Ma, Ying; Zhai, Tianyou
2013-06-11
As a promising candidate for optoelectronics, one-dimensional CdS nanostructures have drawn great scientific and technical interest due to their interesting fundamental properties and possibilities of utilization in novel promising optoelectronical devices with augmented performance and functionalities. This progress report highlights a selection of important topics pertinent to optoelectronical applications of one-dimensional CdS nanostructures over the last five years. This article begins with the description of rational design and controlled synthesis of CdS nanostructure arrays, alloyed nanostructucures and kinked nanowire superstructures, and then focuses on the optoelectronical properties, and applications including cathodoluminescence, lasers, light-emitting diodes, waveguides, field emitters, logic circuits, memory devices, photodetectors, gas sensors, photovoltaics and photoelectrochemistry. Finally, the general challenges and the potential future directions of this exciting area of research are highlighted. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Solar power satellites - Technical, social and political implications
NASA Astrophysics Data System (ADS)
Knelman, F. H.
Solar power satellite systems (SPS) are examined, together with their environmental and social impacts and the energy policies necessary for their construction. The energy source, the sun, is acceptable to advocates of decentralized technologies, while the conversion system is fitted to large institutions. However, large-scale power plants are subject to persistent malfunctions, and the approximately 50 sq km SPS solar array is projected to suffer from at least recurring cell contact failures. The power could also be generated by heat engines for transmission by either laser or microwaves. Numerous feasibility and cost-benefit studies are still required, including defining the transmission beam's effects on the atmosphere, ionosphere, and human health. Furthermore, the resource allocations, capital costs, insurance, and institutional problems still need clarification, as do the design, logistics, and development of an entire new, much larger launch system based on Shuttle technology. Finally, the military defensibility of the SPS power station is questioned.
Micromanipulation by laser microbeam and optical tweezers: from plant cells to single molecules.
Greulich, K O; Pilarczyk, G; Hoffmann, A; Meyer Zu Hörste, G; Schäfer, B; Uhl, V; Monajembashi, S
2000-06-01
Complete manipulation by laser light allows precise and gentle treatment of plant cells, subcellular structures, and even individual DNA molecules. Recently, affordable lasers have become available for the construction of microbeams as well as for optical tweezers. This may generate new interest in these tools for plant biologists. Early experiments, reviewed in this journal, showed that laser supported microinjection of material into plant cells or tissues circumvents mechanical problems encountered in microinjection by fragile glass capillaries. Plant protoplasts could be fused with each other when under microscopical observation, and it was no major problem to generate a triple or quadruple fusion product. In the present paper we review experiments where membrane material was prepared from root hair tips and microgravity was simulated in algae. As many plant cells are transparent, it is possible to work inside living, intact cells. New experiments show that it is possible to release by optical micromanipulation, with high spatial resolutions, intracellular calcium from caged compounds and to study calcium oscillations. An example for avian cardiac tissue is given, but the technique is also suitable for plant cell research. As a more technical tool, optical tweezers can be used to spatially fix subcellular structures otherwise moving inside a cell and thus make them available for investigation with a confocal microscope even when the time for image formation is extended (for example at low fluorescence emission). A molecular biological example is the handling of chromosomes and isolated individual DNA molecules by laser microtools. For example, chromosomes can be cut along complex trajectories, not only perpendicular to their long axis. Single DNA molecules are cut by the laser microbeam and, after coupling such a molecule to a polystrene microbead, are handled in complex geometries. Here, the individual DNA molecules are made visible with a conventional fluorescence microscope by fluorescent dyes such as SYBRGreen. The cutting of a single DNA molecule by molecules of the restriction endonuclease EcoRI can be observed directly, i.e. a type of single molecule restriction analysis is possible. Finally, mechanical properties of individual DNA molecules can be observed directly.
Joint Common Architecture Demonstration (JCA Demo) Final Report
2016-07-28
approach for implementing open systems [16], formerly known as the Modular Open Systems Approach (MOSA). OSA is a business and technical strategy to... TECHNICAL REPORT RDMR-AD-16-01 JOINT COMMON ARCHITECTURE DEMONSTRATION (JCA DEMO) FINAL REPORT Scott A. Wigginton... Modular Avionics .......................................................................... 5 E. Model-Based Engineering
Excimer laser decoating of chromium titanium aluminium nitride to facilitate re-use of cutting tools
NASA Astrophysics Data System (ADS)
Sundar, M.; Whitehead, D.; Mativenga, P. T.; Li, L.; Cooke, K. E.
2009-11-01
This work reports on the technical feasibility and establishment of a process window for removing chromium titanium aluminium nitride (CrTiAlN) coating from steel substrates by laser irradiation. CrTiAlN coating has high hardness and oxidation resistance, with applications for use with cutting tools. The motivation for removing such coatings is to facilitate re-use of tooling by enabling regrinding or reshaping of a worn tool and hence promote sustainable material usage. In this work, laser decoating was performed using an excimer laser. The effect of laser fluence, number of pulses, frequency, scanning speed and laser beam overlap on the decoating performance was investigated in detail. The minimum threshold laser fluence for removing the CrTiAlN coating was lower than that of the steel substrate and this factor is beneficial in controlling the decoating process. Successful laser removal of CrTiAlN coating without noticeable damage to the steel substrate was demonstrated.
Technical advantages of disk laser technology in short and ultrashort pulse processes
NASA Astrophysics Data System (ADS)
Graham, P.; Stollhof, J.; Weiler, S.; Massa, S.; Faisst, B.; Denney, P.; Gounaris, E.
2011-03-01
This paper demonstrates that disk-laser technology introduces advantages that increase efficiency and allows for high productivity in micro-processing in both the nanosecond (ns) and picosecond (ps) regimes. Some technical advantages of disk technology include not requiring good pump beam quality or special wavelengths for pumping of the disk, high optical efficiencies, no thermal lensing effects and a possible scaling of output power without an increase of pump beam quality. With cavity-dumping, the pulse duration of the disk laser can be specified between 30 and hundreds of nanoseconds, but is independent of frequency, thus maintaining process stability. TRUMPF uses this technology in the 750 watts average power laser TruMicro 7050. High intensity, along with fluency, is important for high ablation rates in thinfilm removal. Thus, these ns lasers show high removal rates, above 60 cm2/s, in thin-film solar cell production. In addition, recent results in paint-stripping of aerospace material prove the green credentials and high processing rates inherent with this technology as it can potentially replace toxic chemical processes. The ps disk technology meanwhile is used in, for example, scribing of solar cells, wafer dicing and drilling injector nozzles, as the pulse duration is short enough to minimize heat input in the laser-matter interaction. In the TruMicro Series 5000, the multi-pass regenerative amplifier stage combines high optical-optical efficiencies together with excellent output beam quality for pulse durations of only 6 ps and high pulse energies of up to 0.25 mJ.
Experimental investigation of the laser ablation process on wood surfaces
NASA Astrophysics Data System (ADS)
Panzner, M.; Wiedemann, G.; Henneberg, K.; Fischer, R.; Wittke, Th.; Dietsch, R.
1998-05-01
Processing of wood by conventional mechanical tools like saws or planes leaves behind a layer of squeezed wood only slightly adhering to the solid wood surface. Laser ablation of this layer could improve the durability of coatings and glued joints. For technical applications, thorough knowledge about the laser ablation process is necessary. Results of ablation experiments by excimer lasers, Nd:YAG lasers, and TEA-CO 2 lasers on surfaces of different wood types and cut orientations are shown. The process of ablation was observed by a high-speed camera system and optical spectroscopy. The influence of the experimental parameters are demonstrated by SEM images and measurement of the ablation rate depending on energy density. Thermal effects like melting and also carbonizing of cellulose were found for IR- and also UV-laser wavelengths. Damage of the wood surface after laser ablation was weaker for excimer lasers and CO 2-TEA lasers. This can be explained by the high absorption of wood in the ultraviolet and middle infrared spectral range. As an additional result, this technique provides an easy way for preparing wood surfaces with excellently conserved cellular structure.
Improving laser system productivity through production line integration
NASA Astrophysics Data System (ADS)
Belforte, David A.
1994-09-01
Thousands of laser systems are employed profitably in a variety of industrial applications. These installations have proved successful for economic and technical reasons. And, in certain applications: ceramic scribing, resistor trimming, sheet metal cutting, and air foil drilling, for example, have become the industry standard. Most of these installations are free standing or, at best, part of an off-line manufacturing cell. Examples of laser systems fully integrated into a production line, where the laser process is synchronized with up and down stream manufacturing operation, are rare. The laser has been under utilized in its potential contribution to production line productivity. Current development in laser beam delivery: multiplexing, beam splitting and other distributed energy concepts make the laser an attractive option for just-in-time manufacturing operations. The reasons for this apparent neglect of the laser's full potential are reviewed in this paper, and suggestions for improvement of this situation are offered. Examples of fully integrated laser systems and their successful implementation are described and a forecast of changes in the way lasers contribute to improved productivity and profitability will be made.
Theoretical And Experimental Investigations On The Plasma Of A CO2 High Power Laser
NASA Astrophysics Data System (ADS)
Abel, W.; Wallter, B.
1984-03-01
The CO2 high power laser is increasingly used in material processing. This application of the laser has to meet some requirements: at one hand the laser is a tool free of wastage, but at the other hand is to guarantee that the properties of that tool are constant in time. Therefore power, geometry and mode of the beam have to be stable over long intervalls, even if the laser is used in rough industrial environment. Otherwise laser material processing would not be competitive. The beam quality is affected by all components of the laser - by the CO2 plasma and its IR - amplification, by the resonator which at last generates the beam by optical feedback, and also by the electric power supply whose effects on the plasma may be measured at the laser beam. A transversal flow laser has been developed at the Technical University of Vienna in cooperation with VOest-Alpine AG, Linz (Austria). This laser produces 1 kW of beam power with unfolded resonator. It was subject to investigations presented in this paper.
[SOPHOCLE (Ophthalmologic Simulator of Laser PHOtocoagulation): contribution to virtual reality].
Rouland, J F; Dubois, P; Chaillou, C; Meseuree, P; Karpf, S; Godin, S; Duquenoy, F
1995-01-01
This study was undertaken to teach laser retinal photocoagulation in different disorders using a "virtual eye". Most ophthalmologists routinely use laser photocoagulator. Both indications and laser effects are well-known. However, in various diseases (diabetic retinopathy, age-related-macular degeneration, myopia...) complications rate increase or at least does not decrease. The main reasons are: - ignorance of risk factors, - misuse of the instrument. We developed a new automated device stimulating a real laser photocoagulator. Only slit-lamp exists. The three-mirror lens, the fundus and the retinal photocoagulation impacts are "virtual". The aim of the simulator is to help practitioners to recognize various pathologies almost as in real conditions and to be familiar with different technics of photocoagulation. By using computer assisted learning, a constant evaluation determines the level and the progress of practitioners.
ERIC Educational Resources Information Center
Cutshall, Sandy
2002-01-01
Describes a career and technical education program on photonics, the study, research, and development of equipment and concepts used in the transmission of information through light, including fiber optics and experimental laser technologies. (JOW)
Second Annual Research Center for Optical Physics (RCOP) Forum
NASA Technical Reports Server (NTRS)
Allario, Frank (Editor); Temple, Doyle (Editor)
1995-01-01
The Research Center for Optical Physics (RCOP) held its Second Annual Forum on September 23-24, 1994. The forum consisted of two days of technical sessions with invited talks, submitted talks, and a student poster session. Participants in the technical sessions included students and researchers from CCNY/CUNY, Fisk University, Georgia Institute of Technology, Hampton University, University of Maryland, the Univeristy of Michigan, NASA Langley Research Center, North Caroline A and T University, Steven's Institute of Technology, and NAWC-Warminster. Topics included chaotic lasers, pumped optical filters, nonlinear responses in polythiophene and thiophene based thin films, crystal growth and spectroscopy, laser-induced photochromic centers, raman scattering in phorphyrin, superradiance, doped fluoride crystals, luminescence of terbium in silicate glass, and radiative and nonradiative transitions in rare-earth ions.
76 FR 80226 - Technical Amendments
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-23
... final rule, effective upon publication. Generally, the Administrative Procedure Act (APA) requires a.... Additionally, the APA requires that a final rule must have a delayed effective date of 30 days from the date of... delayed effective date requirement under the APA. 5 U.S.C. 553(d)(3). Again the technical change conforms...
"Type Ia Supernovae: Tools for Studying Dark Energy" Final Technical Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Woosley, Stan; Kasen, Dan
2017-05-10
Final technical report for project "Type Ia Supernovae: Tools for the Study of Dark Energy" awarded jointly to scientists at the University of California, Santa Cruz and Berkeley, for computer modeling, theory and data analysis relevant to the use of Type Ia supernovae as standard candles for cosmology.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-12
... DEPARTMENT OF EDUCATION [CFDA No. 84.326T] National Technical Assistance and Dissemination Center for Children Who Are Deaf-Blind; Final Extension of Project Period and Waiver AGENCY: Office of Special Education Programs, Office of Special Education and Rehabilitative Services, Department of...
TADS Final Evaluation Report, 1980-81. Appendix S.
ERIC Educational Resources Information Center
Suarez, Tanya M.; And Others
The document contains the final report of the Technical Assistance Development System (TADS), a program which provided technical assistance (TA) services to 53 Handicapped Children's Early Education Program (HCEEP) demonstration projects and 13 State Implementation Grants (SIGs). The evaluation report is divided into five sections. Section 1…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meier, W.R.; Bieri, R.L.; Monsler, M.J.
1992-03-01
The primary objective of the of the IFE Reactor Design Studies was to provide the Office of Fusion Energy with an evaluation of the potential of inertial fusion for electric power production. The term reactor studies is somewhat of a misnomer since these studies included the conceptual design and analysis of all aspects of the IFE power plants: the chambers, heat transport and power conversion systems, other balance of plant facilities, target systems (including the target production, injection, and tracking systems), and the two drivers. The scope of the IFE Reactor Design Studies was quite ambitious. The majority of ourmore » effort was spent on the conceptual design of two IFE electric power plants, one using an induction linac heavy ion beam (HIB) driver and the other using a Krypton Fluoride (KrF) laser driver. After the two point designs were developed, they were assessed in terms of their (1) environmental and safety aspects; (2) reliability, availability, and maintainability; (3) technical issues and technology development requirements; and (4) economics. Finally, we compared the design features and the results of the assessments for the two designs.« less
NASA Astrophysics Data System (ADS)
Pais Clemente, Manuel P.
1992-03-01
Lasers are now commonly accepted and widely used surgical instruments in otorhinolaryngology. There have been a great number of technological advances with lasers that have contributed to the expansion of this new surgical modality with an increased number of medical applications. Surgical strategies have also changed and are more favorable toward conservative surgery in which less tissues is removed than with more radical resections. This combination of improving technology and medical attitudes has changed the field of otorhinolaryngology, and resulted in an expanding use of laser surgery. Since 1973 we have been using the carbon dioxide laser in the treatment of diseases of the upper aero digestive systems, learning this new surgical technique from the pioneer work of Strong, Jako, and Vaughan. It is our conviction that a laser surgeon must have a thorough knowledge of laser biophysics, instrumentation, safety protocols, and surgical indications, and have the technical skills to perform laser surgery. Laser technology continues to improve at an increased speed, and it is imperative to update knowledge of current and potential applications of lasers in our specialty. It is the purpose of this article to present our clinical experience of 18 years with the use of lasers in surgery of ORL, emphasizing the carbon dioxide laser.
Laser therapy in the treatment of urological diseases
NASA Astrophysics Data System (ADS)
Nelius, T.; de Riese, W. T.; Reiher, F.; Filleur, S.; Allhoff, E. P.
2006-02-01
Applications of lasers (light amplification by stimulated emission of radiation) in various disciplines of medicine including Urology are well developed. Urology is among the medical specialties that apply many different types of laser systems to treat a broad spectrum of clinical conditions ranging from genital, bladder and urethral tumors to the treatment of benign prostate hyperplasia (BPH), urethral strictures, and stones. The specific application of various laser systems depends on the characteristics of the laser itself, delivery media for the beams, laser-tissue interaction and the desired effect. These complex conditions require an intensive and continuous exchange of information between non-medical researchers and physicians to verify "what is currently technically possible and what is medically needed". Only this exchange can lead to the development of new laser systems. While lasers have become the treatment of choice in some conditions, they could not, despite excellent clinical results, replace conventional therapy options in others. Nonetheless, the use and the introduction of lasers of different wavelengths forces urologists to keep step with the fast developing laser technology. This paper reviews current indications for clinical laser applications relevant to urology and the advantages and disadvantages of using lasers for the management of various urological lesions.
Applications of lasers to production metrology, control, and machine 'Vision'
NASA Astrophysics Data System (ADS)
Pryor, T. R.; Erf, R. K.; Gara, A. D.
1982-06-01
General areas of laser application to production measurement and inspection are reviewed together with the associated laser measurement techniques. The topics discussed include dimensional gauging of part profiles using laser imaging or scanning techniques, laser triangulation for surface contour measurement, surface finish measurement and defect inspection, holography and speckle techniques, and strain measurement. The emerging field of robot guidance utilizing lasers and other sensing means is examined, and, finally, the use of laser marking and reading equipment is briefly discussed.
MRI-Guided Laser Interstitial Thermal Therapy for Epilepsy.
North, Robert Y; Raskin, Jeffrey S; Curry, Daniel J
2017-10-01
MRI-guided laser interstitial thermal therapy for epilepsy (LITT-E) has become an established, minimally invasive alternative to traditional epilepsy surgery. LITT-E is particularly valuable in cases in which open surgery poses unacceptably high morbidity or patient preference precludes craniotomy. Here we present a focused review of technical details and application of LITT to both focal and generalized epilepsy. Copyright © 2017 Elsevier Inc. All rights reserved.
Gaussian-Beam Laser-Resonator Program
NASA Technical Reports Server (NTRS)
Cross, Patricia L.; Bair, Clayton H.; Barnes, Norman
1989-01-01
Gaussian Beam Laser Resonator Program models laser resonators by use of Gaussian-beam-propagation techniques. Used to determine radii of beams as functions of position in laser resonators. Algorithm used in program has three major components. First, ray-transfer matrix for laser resonator must be calculated. Next, initial parameters of beam calculated. Finally, propagation of beam through optical elements computed. Written in Microsoft FORTRAN (Version 4.01).
Modifying a Rodenstock scanning laser ophthalmoscope for imaging densitometry.
Tornow, R P; Beuel, S; Zrenner, E
1997-08-01
The necessary modifications and technical requirements are described for using a commercially available scanning laser ophthalmoscope (Rodenstock Model 101 SLO) as an imaging densitometer to assess human photopigment distribution. The main requirements are a linear detector amplifier, fast shutters for the laser beams, and a trigger unit. Images must be compensated for varying laser intensity. Both rod and cone photopigments are measured with the 514-nm argon laser of the SLO. Discrimination is possible owing to the different spatial distribution. The cone pigment density peaks in the foveal center (D = 0.40) with a steep decrease with increasing eccentricity E (full width at half-maximum, 2.5 degrees ). Rod photopigment increases with increasing eccentricity (D = 0.23 for E = 11 degrees ). These values are in agreement with previous reported results obtained with scanning laser ophthalmoscopes specially designed for retinal densitometry and high stability.
Experiments with Lasers and Frequency Doublers
NASA Technical Reports Server (NTRS)
Bachor, H.-A.; Taubman, M.; White, A. G.; Ralph, T.; McClelland, D. E.
1996-01-01
Solid state laser sources, such as diode-pumped Nd:YAG lasers, have given us CW laser light of high power with unprecedented stability and low noise performance. In these lasers most of the technical sources of noise can be eliminated allowing them to be operated close to the theoretical noise limit set by the quantum properties of light. The next step of reducing the noise below the standard limit is known as squeezing. We present experimental progress in generating reliably squeezed light using the process of frequency doubling. We emphasize the long term stability that makes this a truly practical source of squeezed light. Our experimental results match noise spectra calculated with our recently developed models of coupled systems which include the noise generated inside the laser and its interaction with the frequency doubler. We conclude with some observations on evaluating quadrature squeezed states of light.
Auricular Acupuncture with Laser
Bahr, Frank
2013-01-01
Auricular acupuncture is a method which has been successfully used in various fields of medicine especially in the treatment of pain relief. The introduction of lasers especially low-level lasers into medicine brought besides the already existing stimulation with needles and electricity an additional technique to auricular acupuncture. This literature research looks at the historical background, the development and the anatomical and neurological aspects of auricular acupuncture in general and auricular laser acupuncture in detail. Preliminary scientific findings on auricular acupuncture with laser have been described in detail and discussed critically in this review article. The results of the studies have shown evidence of the effect of auricular laser acupuncture. However, a comparison of these studies was impossible due to their different study designs. The most important technical as well as study parameters were described in detail in order to give more sufficient evidence and to improve the quality of future studies. PMID:23935695
Linear positioning laser calibration setup of CNC machine tools
NASA Astrophysics Data System (ADS)
Sui, Xiulin; Yang, Congjing
2002-10-01
The linear positioning laser calibration setup of CNC machine tools is capable of executing machine tool laser calibraiotn and backlash compensation. Using this setup, hole locations on CNC machien tools will be correct and machien tool geometry will be evaluated and adjusted. Machien tool laser calibration and backlash compensation is a simple and straightforward process. First the setup is to 'find' the stroke limits of the axis. Then the laser head is then brought into correct alignment. Second is to move the machine axis to the other extreme, the laser head is now aligned, using rotation and elevation adjustments. Finally the machine is moved to the start position and final alignment is verified. The stroke of the machine, and the machine compensation interval dictate the amount of data required for each axis. These factors determine the amount of time required for a through compensation of the linear positioning accuracy. The Laser Calibrator System monitors the material temperature and the air density; this takes into consideration machine thermal growth and laser beam frequency. This linear positioning laser calibration setup can be used on CNC machine tools, CNC lathes, horizontal centers and vertical machining centers.
Ultracold molecules for the masses: Evaporative cooling and magneto-optical trapping
NASA Astrophysics Data System (ADS)
Stuhl, B. K.
While cold molecule experiments are rapidly moving towards their promised benefits of precision spectroscopy, controllable chemistry, and novel condensed phases, heretofore the field has been greatly limited by a lack of methods to cool and compress chemically diverse species to temperatures below ten millikelvin. While in atomic physics these needs are fulfilled by laser cooling, magneto-optical trapping, and evaporative cooling, until now none of these techniques have been applicable to molecules. In this thesis, two major breakthroughs are reported. The first is the observation of evaporative cooling in magnetically trapped hydroxyl (OH) radicals, which potentially opens a path all the way to Bose-Einstein condensation of dipolar radicals, as well as allowing cold- and ultracold-chemistry studies of fundamental reaction mechanisms. Through the combination of an extremely high gradient magnetic quadrupole trap and the use of the OH Λ-doublet transition to enable highly selective forced evaporation, cooling by an order of magnitude in temperature was achieved and yielded a final temperature no higher than 5mK. The second breakthrough is the successful application of laser cooling and magneto-optical trapping to molecules. Motivated by a proposal in this thesis, laser cooling of molecules is now known to be technically feasible in a select but substantial pool of diatomic molecules. The demonstration of not only Doppler cooling but also two-dimensional magneto-optical trapping in yttrium (II) oxide, YO, is expected to enable rapid growth in the availability of ultracold molecules—just as the invention of the atomic magneto-optical trap stimulated atomic physics twenty-five years ago.
Photonics workforce education and development in Puerto Rico
NASA Astrophysics Data System (ADS)
Friedman, J. S.; Diaz, A.; Trujillo, E.; Saltares, R.; Floran, L.; Gordillo, R.
2016-09-01
At the Puerto Rico Photonics Institute we have responded to the need of a workforce competitively prepared for entry into the fields of lasers and photonics by creating a 1-year Photonics and Lasers Technical certificate, supported under a grant from the US Department of Labor. The project, entitled New Horizons: Puerto Rico Lasers and Photonics Career Pathways offers displaced workers, veterans, and others in Puerto Rico an opportunity to develop new and highly marketable skills for the 21st century. We give a roadmap of plans and pitfalls, and share our successes, challenges, solutions, and future expectations for those planning similar programs.
History of chemical oxygen-iodine laser (COIL) development in the USA
NASA Astrophysics Data System (ADS)
Truesdell, Keith A.; Helms, Charles A.; Hager, Gordon D.
1994-09-01
This is an overview of the development of Chemical Oxygen-Iodine Laser (COIL) technology in the United States. Key technical developments will be reviewed, beginning in 1960 and culminating in 1977 with the first COIL lasing demonstration at the Air Force Weapons Laboratory (now the Phillips Laboratory). The discussion will then turn to subsonic laser development, supersonic lasing demonstration and efficiency improvements, and finishing with a brief discussion of some spin off COIL technologies. Particular emphasis will be placed on how the O2 (1(Delta) ) generator and O2-I2 mixing nozzle technologies evolved.
History of chemical oxygen-iodine laser (COIL) development in the USA
NASA Astrophysics Data System (ADS)
Truesdell, Keith A.; Helms, Charles A.; Hager, Gordon D.
1995-03-01
This is an overview of the development of Chemical Oxygen-Iodine Laser (COIL) technology in the United States. Key technical developments will be reviewed, beginning in 1960 and culminating in 1977 with the first COIL lasing demonstration at the Air Force Weapons Laboratory (now the Phillips Laboratory). The discussion will then turn to subsonic laser development, supersonic lasing demonstration and efficiency improvements, and finishing with a brief discussion of some spin off COIL technologies. Particular emphasis will be placed on how the O2 (1(Delta) ) generator and O2-I2 mixing nozzle technologies evolved.
Additive Manufacturing in Production: A Study Case Applying Technical Requirements
NASA Astrophysics Data System (ADS)
Ituarte, Iñigo Flores; Coatanea, Eric; Salmi, Mika; Tuomi, Jukka; Partanen, Jouni
Additive manufacturing (AM) is expanding the manufacturing capabilities. However, quality of AM produced parts is dependent on a number of machine, geometry and process parameters. The variability of these parameters affects the manufacturing drastically and therefore standardized processes and harmonized methodologies need to be developed to characterize the technology for end use applications and enable the technology for manufacturing. This research proposes a composite methodology integrating Taguchi Design of Experiments, multi-objective optimization and statistical process control, to optimize the manufacturing process and fulfil multiple requirements imposed to an arbitrary geometry. The proposed methodology aims to characterize AM technology depending upon manufacturing process variables as well as to perform a comparative assessment of three AM technologies (Selective Laser Sintering, Laser Stereolithography and Polyjet). Results indicate that only one machine, laser-based Stereolithography, was feasible to fulfil simultaneously macro and micro level geometrical requirements but mechanical properties were not at required level. Future research will study a single AM system at the time to characterize AM machine technical capabilities and stimulate pre-normative initiatives of the technology for end use applications.
589 nm sum-frequency generation laser for the LGS/AO of Subaru Telescope
NASA Astrophysics Data System (ADS)
Saito, Yoshihiko; Hayano, Yutaka; Saito, Norihito; Akagawa, Kazuyuki; Takazawa, Akira; Kato, Mayumi; Ito, Meguru; Colley, Stephen; Dinkins, Matthew; Eldred, Michael; Golota, Taras; Guyon, Olivier; Hattori, Masayuki; Oya, Shin; Watanabe, Makoto; Takami, Hideki; Iye, Masanori; Wada, Satoshi
2006-06-01
We developed a high power and high beam quality 589 nm coherent light source by sum-frequency generation in order to utilize it as a laser guide star at the Subaru telescope. The sum-frequency generation is a nonlinear frequency conversion in which two mode-locked Nd:YAG lasers oscillating at 1064 and 1319 nm mix in a nonlinear crystal to generate a wave at the sum frequency. We achieved the qualities required for the laser guide star. The power of laser is reached to 4.5 W mixing 15.65 W at 1064 nm and 4.99 W at 1319 nm when the wavelength is adjusted to 589.159 nm. The wavelength is controllable in accuracy of 0.1 pm from 589.060 and 589.170 nm. The stability of the power holds within 1.3% during seven hours operation. The transverse mode of the beam is the TEM 00 and M2 of the beam is smaller than 1.2. We achieved these qualities by the following technical sources; (1) simple construction of the oscillator for high beam quality, (2) synchronization of mode-locked pulses at 1064 and 1319 nm by the control of phase difference between two radio frequencies fed to acousto-optic mode lockers, (3) precise tunability of wavelength and spectral band width, and (4) proper selection of nonlinear optical crystal. We report in this paper how we built up each technical source and how we combined those.
NASA Astrophysics Data System (ADS)
West, Patricia; Baker, Lionel R.
1989-03-01
This paper is a review of the applications of laser scanning in inspection. The reasons for the choice of a laser in flying spot scanning and the optical properties of a laser beam which are of value in a scanning instrument will be given. The many methods of scanning laser beams in both one and two dimensions will be described. The use of one dimensional laser scanners for automatic surface inspection for transmitting and reflective products will be covered in detail, with particular emphasis on light collection techniques. On-line inspection applications which will be mentioned include: photographic film web, metal strip products, paper web, glass sheet, car body paint surfaces and internal cylinder bores. Two dimensional laser scanning is employed in applications where increased resolution, increased depth of focus, and better contrast are required compared with conventional vidicon TV or solid state array cameras. Such examples as special microscope laser scanning systems and a TV compatible system for use in restricted areas of a nuclear reactor will be described. The technical and economic benefits and limitations of laser scanning video systems will be compared with conventional TV and CCD array devices.
Repurposing mainstream CNC machine tools for laser-based additive manufacturing
NASA Astrophysics Data System (ADS)
Jones, Jason B.
2016-04-01
The advent of laser technology has been a key enabler for industrial 3D printing, known as Additive Manufacturing (AM). Despite its commercial success and unique technical capabilities, laser-based AM systems are not yet able to produce parts with the same accuracy and surface finish as CNC machining. To enable the geometry and material freedoms afforded by AM, yet achieve the precision and productivity of CNC machining, hybrid combinations of these two processes have started to gain traction. To achieve the benefits of combined processing, laser technology has been integrated into mainstream CNC machines - effectively repurposing them as hybrid manufacturing platforms. This paper reviews how this engineering challenge has prompted beam delivery innovations to allow automated changeover between laser processing and machining, using standard CNC tool changers. Handling laser-processing heads using the tool changer also enables automated change over between different types of laser processing heads, further expanding the breadth of laser processing flexibility in a hybrid CNC. This paper highlights the development, challenges and future impact of hybrid CNCs on laser processing.
Kronenberg, Peter; Traxer, Olivier
2015-04-01
The purpose of the study was to review the existing literature on holmium:yttrium-aluminum-garnet laser lithotripsy regarding lithotripter settings and laser fibers. An online search of current and past peer-reviewed literature on holmium laser lithotripsy was performed on several databases, including PubMed, SciElo, and Google Scholar. Relevant studies and original articles about lithotripter settings and laser fibers were examined, and the most important information is summarized and presented here. We examine how the choice of lithotripter settings and laser fibers influences the performance of holmium laser lithotripsy. Traditional laser lithotripter settings are analyzed, including pulse energy, pulse frequency, and power levels, as well as newly developed long-pulse modes. The impact of these settings on ablation volume, fragment size, and retropulsion is also examined. Advantages of small- and large-diameter laser fibers are discussed, and controversies are highlighted. Additionally, the influence of the laser fiber is examined, specifically the fiber tip preparation and the lithotripter settings' influence on tip degradation. Many technical factors influence the performance of holmium laser lithotripsy. Knowing and understanding these controllable parameters allows the urologist to perform a laser lithotripsy procedure safely, efficiently, and with few complications.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-28
... Determination Concerning Laser-Based Multi-Function Office Machines AGENCY: U.S. Customs and Border Protection... country of origin of laser-based multi-function office machines. Based upon the facts presented, CBP has... essential character of the laser-based multi-function office machine, and it is at their assembly and...
Optical spectroscopy of laser-produced plasmas for standoff isotopic analysis
NASA Astrophysics Data System (ADS)
Harilal, S. S.; Brumfield, B. E.; LaHaye, N. L.; Hartig, K. C.; Phillips, M. C.
2018-06-01
Rapid, in-field, and non-contact isotopic analysis of solid materials is extremely important to a large number of applications, such as nuclear nonproliferation monitoring and forensics, geochemistry, archaeology, and biochemistry. Presently, isotopic measurements for these and many other fields are performed in laboratory settings. Rapid, in-field, and non-contact isotopic analysis of solid material is possible with optical spectroscopy tools when combined with laser ablation. Laser ablation generates a transient vapor of any solid material when a powerful laser interacts with a sample of interest. Analysis of atoms, ions, and molecules in a laser-produced plasma using optical spectroscopy tools can provide isotopic information with the advantages of real-time analysis, standoff capability, and no sample preparation requirement. Both emission and absorption spectroscopy methods can be used for isotopic analysis of solid materials. However, applying optical spectroscopy to the measurement of isotope ratios from solid materials presents numerous challenges. Isotope shifts arise primarily due to variation in nuclear charge distribution caused by different numbers of neutrons, but the small proportional nuclear mass differences between nuclei of various isotopes lead to correspondingly small differences in optical transition wavelengths. Along with this, various line broadening mechanisms in laser-produced plasmas and instrumental broadening generated by the detection system are technical challenges frequently encountered with emission-based optical diagnostics. These challenges can be overcome by measuring the isotope shifts associated with the vibronic emission bands from molecules or by using the techniques of laser-based absorption/fluorescence spectroscopy to marginalize the effect of instrumental broadening. Absorption and fluorescence spectroscopy probe the ground state atoms existing in the plasma when it is cooler, which inherently provides narrower lineshapes, as opposed to emission spectroscopy which requires higher plasma temperatures to be able to detect thermally excited emission. Improvements in laser and detection systems and spectroscopic techniques have allowed for isotopic measurements to be carried out at standoff distances under ambient atmospheric conditions, which have expanded the applicability of optical spectroscopy-based isotopic measurements to a variety of scientific fields. These technological advances offer an in-situ measurement capability that was previously not available. This review will focus on isotope detection through emission, absorption, and fluorescence spectroscopy of atoms and molecules in a laser-produced plasma formed from a solid sample. A description of the physics behind isotope shifts in atoms and molecules is presented, followed by the physics behind solid sampling of laser ablation plumes, optical methods for isotope measurements, the suitable physical conditions of laser-produced plasma plumes for isotopic analysis, and the current status. Finally, concluding remarks will be made on the existing knowledge/technological gaps identified from the current literature and suggestions for the future work.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-18
...: 84.326Z.] Final Waiver and Extension of the Project Period for the Technical Assistance Coordination... project period. SUMMARY: The Secretary waives the requirements in the Education Department General Administrative Regulations that generally prohibit project periods exceeding five years and extensions of project...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-23
...: Direct final rule. SUMMARY: This direct final rule makes technical changes that will update a requirement that many of our written agreements and memoranda of understanding (MOUs) with other departments..., accordingly, eliminates it. We are making these technical changes to conserve Agency time and resources...
EPA's 1988 regulations concerning USTs are contained in 40 CFR Part 280, 40 CFR Part 281 and 40 CFR Parts 282.50-282.105 and divided into three sections: technical requirements, financial responsibility requirements, and state program approval objectives.
PITTSBURGH TECHNICAL HEALTH TRAINING INSTITUTE DEMONSTRATION PROJECT. FINAL REPORT, VOLUME II.
ERIC Educational Resources Information Center
KISHKUNAS, LOUIS J.
APPENDIXES TO THE "FINAL REPORT," VOLUME I (VT 005 511), ARE INCLUDED--(1) A SCHEMATIC REPRESENTATION OF CURRICULUM DEVELOPMENT, (2) TECHNICAL BEHAVIOR CHECKLISTS, (3) PERFORMANCE INVENTORY FORMS USED IN ON-THE-JOB OBSERVATIONS, (4) REPORT FORM FOR TYPICAL JOB BEHAVIOR OF EMPLOYEE, (5) COOPERATING AREA HEALTH INSTITUTIONS, (6) TABLES OF Z SCORES…
Direct solar pumping of semiconductor lasers: A feasibility study
NASA Technical Reports Server (NTRS)
Anderson, Neal G.
1991-01-01
The primary goals of the feasibility study are the following: (1) to provide a preliminary assessment of the feasibility of pumping semiconductor lasers in space directly focused sunlight; and (2) to identify semiconductor laser structures expected to operate at the lowest possible focusing intensities. It should be emphasized that the structures under consideration would provide direct optical-to-optical conversion of sunlight into laser light in a single crystal, in contrast to a configuration consisting of a solar cell or battery electrically pumping a current injection laser. With external modulation, such lasers may prove to be efficient sources for intersatellite communications. We proposed to develop a theoretical model of semiconductor quantum-well lasers photopumped by a broadband source, test it against existing experimental data where possible, and apply it to estimating solar pumping requirements and identifying optimum structures for operation for operation at low pump intensities. This report outlines our progress toward these goals. Discussion of several technical details are left to the attached summary abstract.
Electronic properties of solids excited with intermediate laser power densities
NASA Astrophysics Data System (ADS)
Sirotti, Fausto; Tempo Beamline Team
Intermediate laser power density up to about 100 GW/cm2 is below the surface damage threshold is currently used to induce modification in the physical properties on short time scales. The absorption of a short laser pulse induces non-equilibrium electronic distributions followed by lattice-mediated equilibrium taking place only in the picosecond range. The role of the hot electrons is particularly important in several domains as for example fast magnetization and demagnetization processes, laser induced phase transitions, charge density waves. Angular resolved photoelectron spectroscopy measuring directly energy and momentum of electrons is the most adapted tool to study the electronic excitations at short time scales during and after fast laser excitations. The main technical problem is the space charge created by the pumping laser pulse. I will present angular resolved multiphoton photoemission results obtained with 800 nm laser pulses showing how space charge electrons emitted during fast demagnetization processes can be measured. Unable enter Affiliation: CNRS-SOLEIL Synchrotron L'Orme des Merisiers , Saint Aubin 91192 Gif sur Yvette France.
Laser Induced Breakdown Spectroscopy of Metals
NASA Astrophysics Data System (ADS)
Palmer, Andria; Lawhead, Carlos; Ujj, Laszlo
2015-03-01
Laser Induced Breakdown Spectroscopy (LIBS) is a very practical spectroscopy to determine the chemical composition of materials. Recent technical developments resulted in equipment used on the MARS Rover by NASA. It is capable of measuring the emission spectra of laser induced plasma created by energetic laser pulses focused on the sample (rocks, metals, etc.). We have develop a Laser Induced Breakdown Spectroscopy setup and investigated the necessary experimental and methodological challenges needed to make such material identification measurements. 355 and 532 nm laser pulses with 5 ns temporal duration was used to generate micro-plasma from which compositions can be determined based on known elemental and molecular emission intensities and wavelengths. The performance of LIBS depends on several parameters including laser wavelength, pulse energy, pulse duration, time interval of observation, geometrical configuration of collecting optics, and the properties of ambient medium. Spectra recorded from alloys (e.g. US penny coin) and pure metals will be presented. Special thanks for the financial support of the Office of Undergraduate Research of UWF.
Invention and Writing in Technical Work: Representing the Object.
ERIC Educational Resources Information Center
Winsor, Dorothy A.
1994-01-01
Describes the way invention is relevant to the practice of technical writing. Studies three engineering students engaged in a real-world project. Shows how the students' technical work and invention for the final report were simultaneous activities. Claims that invention for and through writing overlaps with technical invention. (HB)
Project T.E.A.M. (Technical Education Advancement Modules). Final Report.
ERIC Educational Resources Information Center
Greenville Technical Coll., SC.
Project TEAM (Technical Education Advancement Modules), a cooperative demonstration program for high technology training, created an introductory technical training program and a consumer education package emphasizing the benefits of technical training. The curriculum and training focus of the project began with an assessment of employee needs in…
Fast photocatalytic degradation of methylene blue dye using a low-power diode laser.
Liu, Xianhua; Yang, Yulou; Shi, Xiaoxuan; Li, Kexun
2015-01-01
This study focused on the application of diode lasers as alternative light sources for the fast photocatalytic degradation of methylene blue. The photocatalytic decomposition of methylene blue in aqueous solution under 443 nm laser light irradiation was found to be technically feasible using Ag/AgCl nanoparticles as photocatalysts. The effects of various experimental parameters, such as irradiation time, light source, catalyst loading, initial dye concentration, pH, and laser energy on decolorization and degradation were investigated. The mineralization of methylene blue was confirmed by chemical oxygen demand analysis. The results demonstrate that the laser-induced photocatalytic process can effectively degrade methylene blue under the optimum conditions (pH 9.63, 4 mg/L MB concentration, and 1.4 g/L Ag/AgCl nanoparticles). Copyright © 2014 Elsevier B.V. All rights reserved.
Technical challenges for the future of high energy lasers
NASA Astrophysics Data System (ADS)
LaFortune, K. N.; Hurd, R. L.; Fochs, S. N.; Rotter, M. D.; Pax, P. H.; Combs, R. L.; Olivier, S. S.; Brase, J. M.; Yamamoto, R. M.
2007-02-01
The Solid-State, Heat-Capacity Laser (SSHCL) program at Lawrence Livermore National Laboratory is a multi-generation laser development effort scalable to the megawatt power levels with current performance approaching 100 kilowatts. This program is one of many designed to harness the power of lasers for use as directed energy weapons. There are many hurdles common to all of these programs that must be overcome to make the technology viable. There will be a in-depth discussion of the general issues facing state-of-the-art high energy lasers and paths to their resolution. Despite the relative simplicity of the SSHCL design, many challenges have been uncovered in the implementation of this particular system. An overview of these and their resolution are discussed. The overall system design of the SSHCL, technological strengths and weaknesses, and most recent experimental results will be presented.
1986-12-01
Classification. U Security Marks, Accession *:U00298 AD *. ADA096538 TITLE: Assessment of the Crossed Porro Prism Resonator AUTHOR. Seea, B.A.; Fueloep, K...Laser Range Finder Mechanical Property Stability Resonator Porro Prism Standord Mirror Examine Pgs: 16 Classification: U Security Marks: Accession...Gamma-Ray Laser Graser Mossbauer Effect Borrman Superradiance Nuclear-Magnetic Resonance Pgs: 26 Classification: U Security Marks: Accession *:U00484 AD
1975-04-01
high voltage pulse with an individual mode-locked laser pulse. The switching system was tested using the arrangc- mem shown in fig. 2. The output of...v-0)-f COU-I) 1- 2 10 C^ OHP (p ^ % cP o o ^ o o o .03 .00 .12 .14 „-1/3 .L .16 .18 .20 .22 T (0K) Fl8 + 3m^mr
DOE Office of Scientific and Technical Information (OSTI.GOV)
Semenov, V. A.
2009-06-12
Pulse recirculation has been successfully demonstrated with the interaction laser system of LLNL's Thomson-Radiated Extreme X-ray (T-REX) source. The recirculation increased twenty-eight times the intensity of the light coming out of the laser system, demonstrating the capability of increasing the gamma-ray flux emitted by T-REX. The technical approach demonstrated could conceivably increase the average gamma-ray flux output by up to a hundred times.
77 FR 39623 - Airworthiness Standards: Aircraft Engines; Technical Amendment
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-05
...] Airworthiness Standards: Aircraft Engines; Technical Amendment AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule; technical amendment. SUMMARY: This amendment clarifies aircraft engine... from applicants requesting FAA engine type certifications and aftermarket certifications, such as...
Tomotake, Yoritoki; Ishida, Osamu; Kanitani, Hideo; Ichikawa, Tetsuo
2002-01-01
This article describes a new procedure for immediate implant-supported oral rehabilitation using a photocurable resin skull model and a laser-welding apparatus. Preoperatively, the framework was fabricated on a photocurable resin skull model produced from a CT scan and individually designed guide template. The implants were immediately placed using the guide template; laser welding connected the components of framework. Despite the custom-made prosthesis, the total treatment from implant placement to superstructure placement can be completed within only 1 day. This procedure for immediate implant-supported oral rehabilitation using a photocurable resin skull model and a laser-welding apparatus may be useful for any implant system and patient.
Applications of laser-induced periodic surface structures (LIPSS)
NASA Astrophysics Data System (ADS)
Bonse, Jörn; Kirner, Sabrina V.; Höhm, Sandra; Epperlein, Nadja; Spaltmann, Dirk; Rosenfeld, Arkadi; Krüger, Jörg
2017-02-01
Laser-induced periodic surface structures (LIPSS, ripples) are a universal phenomenon that can be observed on almost any material after the irradiation by linearly polarized laser beams, particularly when using ultrashort laser pulses with durations in the picosecond to femtosecond range. During the past few years significantly increasing research activities have been reported in the field of LIPSS, since their generation in a single-step process provides a simple way of nanostructuring and surface functionalization towards the control of optical, mechanical or chemical properties. In this contribution current applications of LIPSS are reviewed, including the colorization of technical surfaces, the control of surface wetting, the tailoring of surface colonization by bacterial biofilms, and the improvement of the tribological performance of nanostructured metal surfaces.
Laser Processed Condensing Heat Exchanger Technology Development
NASA Technical Reports Server (NTRS)
Hansen, Scott; Wright, Sarah; Wallace, Sarah; Hamilton, Tanner; Dennis, Alexander; Zuhlke, Craig; Roth, Nick; Sanders, John
2017-01-01
The reliance on non-permanent coatings in Condensing Heat Exchanger (CHX) designs is a significant technical issue to be solved before long-duration spaceflight can occur. Therefore, high reliability CHXs have been identified by the Evolvable Mars Campaign (EMC) as critical technologies needed to move beyond low earth orbit. The Laser Processed Condensing Heat Exchanger project aims to solve these problems through the use of femtosecond laser processed surfaces, which have unique wetting properties and potentially exhibit anti-microbial growth properties. These surfaces were investigated to identify if they would be suitable candidates for a replacement CHX surface. Among the areas researched in this project include microbial growth testing, siloxane flow testing in which laser processed surfaces were exposed to siloxanes in an air stream, and manufacturability.
NASA Astrophysics Data System (ADS)
Bousquet, B.; Travaillé, G.; Ismaël, A.; Canioni, L.; Michel-Le Pierrès, K.; Brasseur, E.; Roy, S.; le Hecho, I.; Larregieu, M.; Tellier, S.; Potin-Gautier, M.; Boriachon, T.; Wazen, P.; Diard, A.; Belbèze, S.
2008-10-01
Principal Components Analysis (PCA) is successfully applied to the full laser-induced breakdown spectroscopy (LIBS) spectra of soil samples, defining classes according to the concentrations of the major elements. The large variability of the LIBS data is related to the heterogeneity of the samples and the representativeness of the data is finally discussed. Then, the development of a mobile LIBS system dedicated to the in-situ analysis of soils polluted by heavy metals is described. Based on the use of ten-meter long optical fibers, the mobile system allows deported measurements. Finally, the laser-assisted drying process studied by the use of a customized laser has not been retained to overcome the problem of moisture.
15 CFR 752.11 - Internal Control Programs.
Code of Federal Regulations, 2011 CFR
2011-01-01
... order for several sophisticated lasers. (C) The product ordered is incompatible with the technical level... equipment would be of little use in a country without an electronics industry. (D) The customer has little...
15 CFR 752.11 - Internal Control Programs.
Code of Federal Regulations, 2012 CFR
2012-01-01
... order for several sophisticated lasers. (C) The product ordered is incompatible with the technical level... equipment would be of little use in a country without an electronics industry. (D) The customer has little...
15 CFR 752.11 - Internal Control Programs.
Code of Federal Regulations, 2014 CFR
2014-01-01
... order for several sophisticated lasers. (C) The product ordered is incompatible with the technical level... equipment would be of little use in a country without an electronics industry. (D) The customer has little...
15 CFR 752.11 - Internal Control Programs.
Code of Federal Regulations, 2013 CFR
2013-01-01
... order for several sophisticated lasers. (C) The product ordered is incompatible with the technical level... equipment would be of little use in a country without an electronics industry. (D) The customer has little...
Laser ignition application in a space experiment
NASA Technical Reports Server (NTRS)
Liou, Larry C.; Culley, Dennis E.
1993-01-01
A laser ignition system is proposed for the Combustion Experiment Module on an orbiting spacecraft. The results of a design study are given using the scheduled 'Flame Ball Experiment' as the design guidelines. Three laser ignition mechanisms and wavelengths are evaluated. A prototype laser is chosen and its specifications are given, followed by consideration of the beam optical arrangement, the ignition power requirement, the laser ignition system weight, size, reliability, and laser cooling and power consumption. Electromagnetic interference to the onboard electronics caused by the laser ignition process is discussed. Finally, ground tests are suggested.
Corona Preionization Technique for Carbon Dioxide TEA Lasers.
1982-11-30
34’" " " " "- -. .. " "I~ 82R8O701-02 CORONA PREIONIZATION TECHNIQUE FOR CARBON DIOXIDE TEA LASERS W after R. Kamnki SUnited Technologiles Research Center C...TITLE (and Subtitle) S. TYPE OF REPORT a PERIOD COVERED CORONA PREIONIZATION TECHNIQUE FOR CARBON Final Report DIOXIDE TEA LASERS May 5, 1981...Preionization Laser UV Preionization Pulsed CO2 Laser Corona Preionization CO2 TEA Laser 10. ABSTRACT (Continue on reverse side If neceeeiny md Identify
Heat damage-free laser-microjet cutting achieves highest die fracture strength
NASA Astrophysics Data System (ADS)
Perrottet, Delphine; Housh, Roy; Richerzhagen, Bernold; Manley, John
2005-04-01
Unlike conventional laser-based technologies, the water jet guided laser does not generate heat damage and contamination is also very low. The negligible heat-affected zone is one reason why die fracture strength is higher than with sawing. This paper first presents the water jet guided laser technology and then explains how it differs from conventional dry laser cutting. Finally, it presents the results obtained by three recent studies conducted to determine die fracture strength after Laser-Microjet cutting.
Small image laser range finder for planetary rover
NASA Technical Reports Server (NTRS)
Wakabayashi, Yasufumi; Honda, Masahisa; Adachi, Tadashi; Iijima, Takahiko
1994-01-01
A variety of technical subjects need to be solved before planetary rover navigation could be a part of future missions. The sensors which will perceive terrain environment around the rover will require critical development efforts. The image laser range finder (ILRF) discussed here is one of the candidate sensors because of its advantage in providing range data required for its navigation. The authors developed a new compact-sized ILRF which is a quarter of the size of conventional ones. Instead of the current two directional scanning system which is comprised of nodding and polygon mirrors, the new ILRF is equipped with the new concept of a direct polygon mirror driving system, which successfully made its size compact to accommodate the design requirements. The paper reports on the design concept and preliminary technical specifications established in the current development phase.
CυBE: Coherent υ Beam Educator
NASA Astrophysics Data System (ADS)
Sureshkumar, Vivian Amos; Richardson, M.
2017-03-01
Holography has advanced rapidly over the years due to technical melioration in the field of optics. Three-dimensional imaging has gained importance to upgrade the existing imaging and display system. Holography has become one of the branches of optics gaining significant importance with a vast number of technical and industrial applications. When we address holography the first thing that comes to mind is projecting a three dimensional object on thin air. The word holography has always been confused between peppers ghost effect. The famous English phrase "A picture is worth a thousand words", means a complex idea can be conveyed by a single picture. The basic principle of holography sounds complex with all its technical terms. This paper aims to explain the concept of the CυBE: Coherent υ Beam Educator that contains a transmission hologram illuminated with a laser diode. This paper summarizes the construction details of the CυBE and the optical setup to record the transmission hologram. It also briefs the circuit connections for the laser diode that's works with an aid of a push button. When viewer presses the push button the original scene is reconstructed. It provides details regarding the angle of reference beam at recording and how the reference beam is compensated at reconstruction. Also this paper highlights how the magnification of the recorded image is affected with respect to the path length of the laser diode inside the box during reconstruction of the recorded hologram.
Impact of initial surface parameters on the final quality of laser micro-polished surfaces
NASA Astrophysics Data System (ADS)
Chow, Michael; Bordatchev, Evgueni V.; Knopf, George K.
2012-03-01
Laser micro-polishing (LμP) is a new laser-based microfabrication technology for improving surface quality during a finishing operation and for producing parts and surfaces with near-optical surface quality. The LμP process uses low power laser energy to melt a thin layer of material on the previously machined surface. The polishing effect is achieved as the molten material in the laser-material interaction zone flows from the elevated regions to the local minimum due to surface tension. This flow of molten material then forms a thin ultra-smooth layer on the top surface. The LμP is a complex thermo-dynamic process where the melting, flow and redistribution of molten material is significantly influenced by a variety of process parameters related to the laser, the travel motions and the material. The goal of this study is to analyze the impact of initial surface parameters on the final surface quality. Ball-end micromilling was used for preparing initial surface of samples from H13 tool steel that were polished using a Q-switched Nd:YAG laser. The height and width of micromilled scallops (waviness) were identified as dominant parameter affecting the quality of the LμPed surface. By adjusting process parameters, the Ra value of a surface, having a waviness period of 33 μm and a peak-to-valley value of 5.9 μm, was reduced from 499 nm to 301 nm, improving the final surface quality by 39.7%.
NASA Technical Reports Server (NTRS)
1974-01-01
The results of the LAGEOS thermal/optical/vibrational analysis and test program are reported. Through analyses and tests it is verified that the MSFC LAGEOS design provides a retroreflector thermal environment which maintains acceptable retroflector internal thermal gradients. The technical results of the study, organized by the major task areas are presented. The interrelationships of the major tasks are described and the major decisions are identified.
Conduction cooled compact laser for chemcam instrument
NASA Astrophysics Data System (ADS)
Faure, B.; Saccoccio, M.; Maurice, S.; Durand, E.; Derycke, C.
2017-11-01
A new conduction cooled compact laser for Laser Induced Breakdown Spectroscopy (LIBS) on Mars is presented. The laser provides pulses with energy higher than 30mJ at 1μm of wavelength with a good spatial quality. Three development prototypes of this laser have been built and functional and environmental tests have been done. Then, the Qualification and Flight models have been developed and delivered. A spare model is now developed. This laser will be mounted on the ChemCam Instrument of the NASA mission MSL 2009. ChemCam Instrument is developed in collaboration between France (CESR and CNES) and USA (LANL). The goal of this Instrument is to study the chemical composition of Martian rocks. A laser source (subject of this presentation) emits a pulse which is focused by a telescope. It creates a luminous plasma on the rock; the light of this plasma is then analysed by three spectrometers to obtain information on the composition of the rock. The laser source is developed by the French company Thales Laser, with a technical support from CNES and CESR. This development is funded by CNES. The laser is compact, designed to work in burst mode. It doesn't require any active cooling.
Advances in laser technology and fibre-optic delivery systems in lithotripsy.
Fried, Nathaniel M; Irby, Pierce B
2018-06-08
The flashlamp-pumped, solid-state holmium:yttrium-aluminium-garnet (YAG) laser has been the laser of choice for use in ureteroscopic lithotripsy for the past 20 years. However, although the holmium laser works well on all stone compositions and is cost-effective, this technology still has several fundamental limitations. Newer laser technologies, including the frequency-doubled, double-pulse YAG (FREDDY), erbium:YAG, femtosecond, and thulium fibre lasers, have all been explored as potential alternatives to the holmium:YAG laser for lithotripsy. Each of these laser technologies is associated with technical advantages and disadvantages, and the search continues for the next generation of laser lithotripsy systems that can provide rapid, safe, and efficient stone ablation. New fibre-optic approaches for safer and more efficient delivery of the laser energy inside the urinary tract include the use of smaller-core fibres and fibres that are tapered, spherical, detachable or hollow steel, or have muzzle brake distal fibre-optic tips. These specialty fibres might provide advantages, including improved flexibility for maximal ureteroscope deflection, reduced cross section for increased saline irrigation rates through the working channel of the ureteroscope, reduced stone retropulsion for improved stone ablation efficiency, and reduced fibre degradation and burnback for longer fibre life.
Simulation of planetary entry radiative heating with a CO2 gasdynamic laser
NASA Technical Reports Server (NTRS)
Lundell, J. H.; Dickey, R. R.; Howe, J. T.
1975-01-01
Heating encountered during entry into the atmospheres of Jupiter, Saturn, and Uranus is described, followed by a discussion of the use of a CO2 gasdynamic laser to simulate the radiative component of the heating. Operation and performance of the laser is briefly described. Finally, results of laser tests of some candidate heat-shield materials are presented.
Suppression of Laser Shot Noise Using Laser-Cooled OptoMechanical Systems
2010-04-22
that this device will be able to demonstrate squeezing in a fairly short time . Background: The goal of this effort was to create laser light with...The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing...REPORT Final report on Seedling project: "Suppression of Laser Shot Noise Using Laser -Cooled Opto-Mechanical Systems" 14. ABSTRACT 16. SECURITY
WDM Nanoscale Laser Diodes for Si Photonic Interconnects
2016-07-25
mounting on silicon. The nanoscale VCSELs can achieve small optical modes and present a compact laser diode that is also robust. In this work we have used...Distribution Unlimited UU UU UU UU 25-07-2016 1-Feb-2012 31-Dec-2015 Final Report: WDM Nanoscale Laser Diodes for Si Photonic Interconnects The views...P.O. Box 12211 Research Triangle Park, NC 27709-2211 VCSEL, optical interconnect, laser diode , semiconductor laser, microcavity REPORT DOCUMENTATION
Electron-Beam Vapor Deposition of Mold Inserts Final Report CRADA No. TSB-777-94
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shepp, T.; Feeley, T.
Lawrence Livermore National Laboratory and H.G.G. Laser Fare, Inc. studied the application of electron-beam vapor deposition technology to the production of mold inserts for use in an injection molding machine by Laser Fare. Laser Fare provided LLNL with the requirements of the mold inserts as well as sample inserts. LLNL replicated the mold insert(s) to Laser Fare for testing by Laser Fare.
7 CFR 652.36 - Appeal of decertification decisions.
Code of Federal Regulations, 2010 CFR
2010-01-01
... technical service provider's written appeal, the Chief or his designee, will make a final determination, in... CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE SUPPORT ACTIVITIES TECHNICAL SERVICE PROVIDER ASSISTANCE... of the State Conservationist's decertification determination, the technical service provider may...
[Experimental investigations of CO2 laser application in middle ear ossicles].
Dazert, S; Russ, D; Mlynski, R; Brors, D; Greiner, A; Aletsee, C; Helms, J
2003-07-01
During the last few years, several laser systems have been applied for procedures in middle ear surgery. In this study, we determined the technical parameters for the dissection of the middle ear ossicles with the CO(2) laser and analyzed the histological findings. The malleus necks of 16 human temporal bones were dissected under standardized conditions using a CO(2) laser with a power output between 35 and 55 kW/cm(2). The specimens were fixed and histological probes of 50- micro m thickness were prepared. The laser outputs led to crater diameters from 0.14 to 0.55 mm. As an analogy between laser energy and thermal tissue destruction, three zones of thermal damage were differentiated: a cinder zone, a carbonization zone, and a zone of dehydration. The metrical dimensions of these zones did not show any correlation to the applied laser energy. The data of this study show that commercially available CO(2) lasers are sufficient for a safe and effective partial resection of middle ear ossicles using a power output of 35 kW/cm(2).
A new solid-state, frequency-doubled neodymium-YAG photocoagulation system.
Jalkh, A E; Pflibsen, K; Pomerantzeff, O; Trempe, C L; Schepens, C L
1988-06-01
We have developed a solid-state laser system that produces a continuous green monochromatic laser beam of 532 nm by doubling the frequency of a neodymium-YAG laser wavelength of 1064 nm with a potassium-titamyl-phosphate crystal. Photocoagulation burns of equal size and intensity were placed in two rabbit eyes with the solid-state laser system and the regular green argon laser system, respectively, using the same slit-lamp mode of delivery. Histologic findings of lesion sections revealed no important differences between the two systems. In theory, the longer wavelength of the solid-state laser offers the advantages of less scattering in ocular media, higher absorption by oxyhemoglobin, and less absorption by macular xanthophyll than the 514-nm wavelength of the regular green argon laser. The solid-state laser has impressive technical advantages: it contains no argon-ion gas tube that wears out and is expensive to replace; it is much more power efficient, and thus considerably smaller and compact; it is sturdier and easily movable; it does not require external cooling; it uses a 220-V monophasic alternating current; and it requires little maintenance.
Capturing Cognitive Fingerprints for Active Authentication
2014-10-01
CAPTURING COGNITIVE FINGERPRINTS FOR ACTIVE AUTHENTICATION IOWA STATE UNIVERSITY OF SCIENCE & TECHNOLOGY OCTOBER 2014 FINAL TECHNICAL REPORT...REPORT TYPE FINAL TECHNICAL REPORT 3. DATES COVERED (From - To) SEP 2013 – APR 2014 4. TITLE AND SUBTITLE CAPTURING COGNITIVE FINGERPRINTS FOR ACTIVE...The project ended before the IRB application was approved. 15. SUBJECT TERMS Active Authentication, Cognitive Fingerprints , Biometric Modalities
ERIC Educational Resources Information Center
Morgan, Robert P.
Research is summarized in a brief final report built around a four-section bibliography. The first section lists periodic progress reports and articles which provide an overview of the program, including articles which pertain primarily to educational rather than technical aspects of satellite utilization. Theses carried out in the fields of…
Evaluation of 3-D Laser Scanning Equipment : 2018 Final Report
DOT National Transportation Integrated Search
2018-05-01
As a follow-up to ICT Project R27-030, Evaluation of 3-D Laser Scanning, this report provides findings of an evaluation of 3-D laser scanning equipment to determine the tangible costs versus benefits and the manpower savings realized by using the equ...
Head Start Impact Study. Technical Report
ERIC Educational Resources Information Center
Puma, Michael; Bell, Stephen; Cook, Ronna; Heid, Camilla; Shapiro, Gary; Broene, Pam; Jenkins, Frank; Fletcher, Philip; Quinn, Liz; Friedman, Janet; Ciarico, Janet; Rohacek, Monica; Adams, Gina; Spier, Elizabeth
2010-01-01
This Technical Report is designed to provide technical detail to support the analysis and findings presented in the "Head Start Impact Study Final Report" (U.S. Department of Health and Human Services, January 2010). Chapter 1 provides an overview of the Head Start Impact Study and its findings. Chapter 2 provides technical information on the…
ERIC Educational Resources Information Center
Sommers, Paul; Heg, Deena
A project was conducted to improve the state of Washington's community and technical college system by developing and using an improved occupational forecasting system to assess and respond to education and training needs. First, long-term occupational forecast data from Washington's Employment Security Department were matched with technical and…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-04
... Preparation of Market-Based Rate Filings and Electric Quarterly Reports by Public Utilities; Notice of Technical Conference January 28, 2010. Take notice that Commission staff will convene a technical conference... final agenda of the technical conference. The March 3, 2010 technical conference will focus on the...
A Revision of Technical Mathematics Based on the NCTM Standards. Final Report.
ERIC Educational Resources Information Center
Near, Barbara
Between 1993 and 1996, Henry Ford Community College (Michigan) worked with business, industry, and technical instructors to revise their Technical Mathematics program in accordance with the National Council of Teachers of Mathematics (NCTM) Standards. The purpose of the project was to restructure the technical math curriculum and create a context…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-02
... SECURITIES AND EXCHANGE COMMISSION 17 CFR Part 240 [Release No. 34-63949] Technical Amendments to...: Securities and Exchange Commission. ACTION: Final rule; technical amendments. SUMMARY: The Securities and Exchange Commission (``Commission'') is adopting technical amendments to Rule 17a-8 under the Securities...
2013-05-20
The Assistant Secretary for Special Education and Rehabilitative Services announces a priority under the Technical Assistance to Improve State Data Capacity program. The Assistant Secretary may use this priority for competitions in fiscal year (FY) 2013 and later years. We take this action to focus attention on an identified national need to provide technical assistance (TA) to States to improve their capacity to meet the data collection and reporting requirements of the Individuals with Disabilities Education Act (IDEA). We intend this priority to establish a TA center to improve State capacity to accurately collect and report IDEA data (Data Center).
Technical Evaluation Motor No. 10 (TEM-10)
NASA Technical Reports Server (NTRS)
1993-01-01
Technical Evaluation Motor No. 10 (TEM-10) was static fired on 27 Apr. 1993 at the Thiokol Corporation full-scale motor static test bay, T-24. This final test report documents the procedures, performance, and results of the static test firing of TEM-10. All observations, discussions, conclusions, and recommendations contained are final. Included is a presentation and discussion of TEM-10 performance, anomalies, and test results in concurrence with the objectives outlined in CTP-0110, Revision D, Space Shuttle Technical Evaluation Motor No. 10 (TEM-10) Static Fire Test Plan.
2014-08-05
The Assistant Secretary for the Office of Special Education and Rehabilitative Services (OSERS) announces a priority under the Technical Assistance on State Data Collection program. The Assistant Secretary may use this priority for competitions in fiscal year (FY) 2014 and later years. We take this action to fund a cooperative agreement to establish and operate an IDEA Data Management Center (Center) that will provide technical assistance (TA) to improve the capacity of States to meet the data collection requirements of the Individuals with Disabilities Education Act (IDEA).
2016-05-31
and included explosives such as TATP, HMTD, RDX, RDX, ammonium nitrate , potassium perchlorate, potassium nitrate , sugar, and TNT. The approach...Distribution Unlimited UU UU UU UU 31-05-2016 15-Apr-2014 14-Jan-2015 Final Report: Technical Topic 3.2.2. d Bayesian and Non- parametric Statistics...of Papers published in non peer-reviewed journals: Final Report: Technical Topic 3.2.2. d Bayesian and Non-parametric Statistics: Integration of Neural
Laser-induced selective metallization of polypropylene doped with multiwall carbon nanotubes
NASA Astrophysics Data System (ADS)
Ratautas, Karolis; Gedvilas, Mindaugas; Stankevičiene, Ina; Jagminienė, Aldona; Norkus, Eugenijus; Pira, Nello Li; Sinopoli, Stefano; Račiukaitis, Gediminas
2017-08-01
Moulded interconnect devices (MID) offer the material, weight and cost saving by integration electronic circuits directly into polymeric components used in automotive and other consumer products. Lasers are used to write circuits directly by modifying the surface of polymers followed by an electroless metal plating. A new composite material - the polypropylene doped with multiwall carbon nanotubes was developed for the laser-induced selective metallization. Mechanism of surface activation by laser irradiation was investigated in details utilising pico- and nanoseconds lasers. Deposition of copper was performed in the autocatalytic electroless plating bath. The laser-activated polymer surfaces have been studied using the Raman spectroscopy and scanning electron microscope (SEM). Microscopic images revealed that surface becomes active only after its melting by a laser. Alterations in the Raman spectra of the D and G bands indicated the clustering of carbon additives in the composite material. Optimal laser parameters for the surface activation were found by measuring a sheet resistance of the finally metal-plated samples. A spatially selective copper plating was achieved with the smallest conductor line width of 22 μm at the laser scanning speed of 3 m/s and the pulse repetition rate of 100 kHz. Finally, the technique was validated by making functional electronic circuits by this MID approach.
A portable lidar using a diode-pumped YAG laser
NASA Technical Reports Server (NTRS)
Takeuchi, N.; Okumura, H.; Sugita, T.; Matsumoto, H.; Yamaguchi, S.
1992-01-01
A Mie lidar system is technically established and is used for monitoring air pollution, stratospheric and boundary layer aerosol distribution, plume dispersion, visibility, and the study of atmospheric structure and cloud physics. However, a lidar system is not widely used because of its cumbersome handling and unwieldy portability. Although the author developed a laser diode lidar system based on RM-CW technique, it has a limit of measurement distance. Here we report the development of an all solid Mie lidar system using a diode-pumped Nd:YAG laser and a Si-APD detector. This was constructed as a prototype of a handy lidar system.
Lower-free tropospheric ozone dial measurements over Athens, Greece
NASA Astrophysics Data System (ADS)
Mytilinaios, Michail; Papayannis, Alexandros; Tsaknakis, Georgios
2018-04-01
A compact ozone differential absorption lidar (DIAL) was implemented at the Laboratory of Laser Remote Sensing of the National Technical University of Athens (NTUA), in Athens, Greece. The DIAL system is based on a Nd:YAG laser emitting at 266 nm. A high-pressure Raman cell, filled with D2, was used to generate the λON and λOFF laser wavelength pairs (i.e., 266-289 nm and 289-316 nm, respectively) based on the Stimulated Raman Scattering (SRS) effect. The system was run during daytime and nighttime conditions to obtain the vertical profile of tropospheric ozone in the Planetary Boundary Layer (PBL) and the adjacent free troposphere.
Mechanism of Surface Reinforcement of Steels by Nanocarbon Materials Using Laser Heating
NASA Astrophysics Data System (ADS)
Bocharov, G. S.; Eletskii, A. V.; Zilova, O. S.; Terentyev, E. V.; Fedorovich, S. D.; Chudina, O. V.; Churilov, G. N.
2018-02-01
The mechanism of the surface reinforcement and wear resistance of steel products are studied as a result of creating the strengthening layers with the nanocarbon using the laser heating. Laser surface treatment using soot remaining after fullerene extraction leads to a more than fivefold increase in the microhardness (up to 1086 HV) and a decrease in the friction coefficient by 20-30%. The conclusion that the reinforcement mechanism involves the formation of eutectic, cementite, martensite, the cellular substructure, and grain refinement is carried out based on metallographic studies of the strengthened layers of technically pure iron with a thickness of 20-70 μm.
Grayscale photomask fabricated by laser direct writing in metallic nano-films.
Guo, Chuan Fei; Cao, Sihai; Jiang, Peng; Fang, Ying; Zhang, Jianming; Fan, Yongtao; Wang, Yongsheng; Xu, Wendong; Zhao, Zhensheng; Liu, Qian
2009-10-26
The grayscale photomask plays a key role in grayscale lithography for creating 3D microstructures like micro-optical elements and MEMS structures, but how to fabricate grayscale masks in a cost-effective way is still a big challenge. Here we present novel low cost grayscale masks created in a two-step method by laser direct writing on Sn nano-films, which demonstrate continuous-tone gray levels depended on writing powers. The mechanism of the gray levels is due to the coexistence of the metal and the oxides formed in a laser-induced thermal process. The photomasks reveal good technical properties in fabricating 3D microstructures for practical applications.
Exploring Broad Area Quantum Cascade Lasers
2017-10-01
Research Laboratory AFRL /RDLTD 3550 Aberdeen Ave SE Kirtland AFB, NM 87117-5776 11. SPONSOR/MONITOR’S REPORT NUMBER(S) AFRL -RD-PS-TP-2017-0008 12...LIST DTIC/OCP 8725 John J. Kingman Rd, Suite 0944 Ft Belvoir, VA 22060-6218 1 cy AFRL /RVIL Kirtland AFB, NM 87117-5776 1 cy Chunte Lu... AFRL -RD-PS- AFRL -RD-PS- TP-2017-0008 TP-2017-0008 EXPLORING BROAD AREA QUANTUM CASCADE LASERS Tim Newell, et. al. 1 October 2017 Technical
Studies of Optical Beam Phase-Conjugation and Electromagnetic Scattering Process
1992-05-05
34 S.M. Jensen and R.W. Hellwarth, Appl. Phys. Lett., 33 404, September, 1978. 3.3. " Infrared -to--optical image conversion by Bragg reflection from...paper WW2 at the 1988 Conference on Lasers and Electrooptics. 27 April 1988 at Anaheim, California. Abstract in Conference Bulletin. Summary published...in Technical Digest. Conference on Lasers and Electro-Optics (Optical Society of America, Washington, D.C., 1988). Paper WW2 . 16 4.74. "Fidelity of
Translations on Telecommunications Policy, Research and Development No. 2
1977-05-24
Frequencies 44 LATIN AMERICA ARGENTINA Laser-Radio Experiment Conducted in La Plata (TELAM, 5 May 77) ^5 NEAR EAST AND AFRICA INTER-ARAB AFFAIRS...LD] CSO: 5500 44 ARGENTINA LASER-RADIO EXPERIMENT CONDUCTED IN LA PLATA Buenos Aires TELAM in Spanish 1445 GMT 5 May 77 PY [Excerpts] La Plata...held at Radio Universidad of La Plata during the record- ing of a program to be broadcast at 2030 tonight. Technical preparations for the experiment
Annual Technical Report, Materials Research Laboratory, July 1, 1973-June 30, 1974
1974-06-30
Office, Durham (AROD) Picosecond Laser Research An Experimental study of the linear growth region of ultrashort pulse generation was made. The pulse ...Experimental Study of the Linear Growth Region of Ultrashort - Pulse Generation in a Mode-locked Nd:glass Laser ," Appl. Phys. Letters 24, 631 (1974...the loading pulse which may be incident from any direction, and the onset of fast fracture. The dependence of the delay time on the pulse intensity
Fibre Laser Welding of HY-80 Steel: Procedure Development and Testing
2010-09-01
2 Welding The material used in this study was quenched and tempered martensitic HY80 steel which conforms to MIL-S-1621 [2]. The testing...Journal, 1977. [4] AWS, D1.6 in Structural Welding Code Stainless Steel . 2007, American Welding Society: Miami Florida. [5] DefStan, 02-770 Part 2...Canada Fibre Laser Welding of HY-80 Steel Proceedure Development and Testing Christopher Bayley DLP Neil Aucoin DLP Xinjin Cao NRC IAR AMTC Technical
DOT National Transportation Integrated Search
2016-10-01
Laser-induced breakdown spectroscopy (LIBS) has been studied as a fast method of detecting chlorine in concrete samples. Both single pulse (SP) and double pulse (DP) experiments have been tested. Several combinations of lasers (Neodymium-Yttrium Alum...
Analysis of optical scheme for medium-range directed energy laser weapon system
NASA Astrophysics Data System (ADS)
Jabczyński, Jan K.; Kaśków, Mateusz; Gorajek, Łukasz; Kopczyński, Krzysztof
2017-10-01
The relations between range of operation and aperture of laser weapon system were investigated, taking into account diffraction and technical limitations as beam quality, accuracy of point tracking, technical quality of optical train, etc. As a result for the medium ranges of 1 - 2 km we restricted the analysis to apertures not wider than 150 mm and the optical system without adaptive optics. To choose the best laser beam shape, the minimization of aperture losses and thermooptical effects inside optics as well as the effective width of laser beam in far field should be taken into account. We have analyzed theoretically such a problem for the group of a few most interesting from that point of view profiles including for reference two limiting cases of Gaussian beam and `top hat' profile. We have found that the most promising is the SuperGaussian profile of index p = 2 for which the surfaces of beam shaper elements can be manufactured in the acceptable cost-effective way and beam quality does not decrease noticeably. Further, we have investigated the thermo-optic effects on the far field parameters of Gaussian and `top hat' beams to determine the influence of absorption in optical elements on beam quality degradation. The simplified formulae were derived for beam quality measures (parameter M2 and Strehl ratio) which enables to estimate the influence of absorption losses on degradation of beam quality.
NASA Astrophysics Data System (ADS)
Marya, Manuel; Singh, Virendra; Marya, Surendar; Hascoet, Jean Yves
2015-08-01
Additive manufacturing (AM) brings disruptive changes to the ways parts, and products are designed, fabricated, tested, qualified, inspected, marketed, and sold. These changes introduce novel technical challenges and concerns arising from the maturity and diversity of today's AM processes, feedstock materials, and process parameter interactions. AM bears a resemblance with laser and electron beam welding in the so-called conduction mode, which involves a multitude of dynamic physical events between the projected feedstock and a moving heat source that eventually influence AM part properties. For this paper, an air vent was selected for its thin-walled, hollow, and variable cross section, and limited size. The studied air vents, randomly selected from a qualification batch, were fabricated out of 316L stainless steel using a 4 kW fiber laser powder-fed AM system, referred to as construction laser additive direct (CLAD). These were systematically characterized by microhardness indentation, visual examination, optical and scanning electron microscopy, and electron-back-scattering diffraction in order to determine AM part suitability for service and also broadly discuss metallurgical phenomena. The paper then briefly expands the discussion to include additional engineering alloys and further analyze relationships between AM process parameters and AM part properties, consistently utilizing past experience with the same powder-fed CLAD 3D printer, the well-established science and technology of welding and joining, and recent publications on additive manufacturing.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rambo, Patrick; Schwarz, Jens; Kimmel, Mark
We have developed high damage threshold filters to modify the spatial profile of a high energy laser beam. The filters are formed by laser ablation of a transmissive window. The ablation sites constitute scattering centers which can be filtered in a subsequent spatial filter. Finally, by creating the filters in dielectric materials, we see an increased laser-induced damage threshold from previous filters created using ‘metal on glass’ lithography.
Rambo, Patrick; Schwarz, Jens; Kimmel, Mark; ...
2016-09-27
We have developed high damage threshold filters to modify the spatial profile of a high energy laser beam. The filters are formed by laser ablation of a transmissive window. The ablation sites constitute scattering centers which can be filtered in a subsequent spatial filter. Finally, by creating the filters in dielectric materials, we see an increased laser-induced damage threshold from previous filters created using ‘metal on glass’ lithography.
Applications of Laser Scattering Probes to Turbulent Diffusion Flames
1983-11-01
APPLICATIONS OF LASER SCATTERING PROBES TO TURBULENT DIFFUSION FLAMES u ^ j FINAL REPORT Contract N00014-80-C-0882 Submitted to Office of...Include Security Classification) Applications of Laser Scattering Probes to Turbulent Diffusion Flames PROJECT NO. TASK NO. WORK UNIT NO. 12...for a co-flowing jet turbulent diffusion flame, and planar laser-induced fluorescence to provide two- dimensional instantaneous images of the flame
Willie, Jon T.; Laxpati, Nealen G.; Drane, Daniel L.; Gowda, Ashok; Appin, Christina; Hao, Chunhai; Brat, Daniel J.; Helmers, Sandra L.; Saindane, Amit; Nour, Sherif G.; Gross, Robert E.
2014-01-01
Background Open surgery effectively treats mesial temporal lobe epilepsy (MTLE), but carries risks of neurocognitive deficits, which may be reduced with minimally invasive alternatives. Objective To describe technical and clinical outcomes of stereotactic laser amygdalohippocampotomy (SLAH) with real-time magnetic resonance thermal imaging (MRTI) guidance. Methods Under general anesthesia and utilizing standard stereotactic methods, 13 adult patients with intractable MTLE (with and without mesial temporal sclerosis, MTS) prospectively underwent insertion of a saline-cooled fiber-optic laser applicator into amygdalohippocampal structures from an occipital trajectory. Computer-controlled laser ablation was performed during continuous MRTI followed by confirmatory contrast-enhanced anatomic imaging and volumetric reconstruction. Clinical outcomes were determined from seizure diaries. Results A mean 60% volume of the amygdalohippocampal complex was ablated in 13 patients (9 with MTS) undergoing 15 procedures. Median hospitalization was one day. With follow-up ranging from 5-26 (median 14) months, 77% (10/13) of patients achieved meaningful seizure reduction, of which 54% (7/13) were free of disabling seizures. Of patients with preoperative MTS, 67% (6/9) achieved seizure freedom. All recurrences were observed by<6 months. Variances in ablation volume and length did not account for individual clinical outcomes. Whereas no complications of laser therapy itself were observed, one significant complication, a visual field defect, resulted from deviated insertion of a stereotactic aligning rod, which was corrected prior to ablation. Conclusion Real-time MR-guided SLAH is a technically novel, safe, and effective alternative to open surgery. Further evaluation with larger cohorts over time is warranted. PMID:24618797
NASA Astrophysics Data System (ADS)
Reid, Derryck T.; Heyl, Christoph M.; Thomson, Robert R.; Trebino, Rick; Steinmeyer, Günter; Fielding, Helen H.; Holzwarth, Ronald; Zhang, Zhigang; Del'Haye, Pascal; Südmeyer, Thomas; Mourou, Gérard; Tajima, Toshiki; Faccio, Daniele; Harren, Frans J. M.; Cerullo, Giulio
2016-09-01
The year 2015 marked the 25th anniversary of modern ultrafast optics, since the demonstration of the first Kerr lens modelocked Ti:sapphire laser in 1990 (Spence et al 1990 Conf. on Lasers and Electro-Optics, CLEO, pp 619-20) heralded an explosion of scientific and engineering innovation. The impact of this disruptive technology extended well beyond the previous discipline boundaries of lasers, reaching into biology labs, manufacturing facilities, and even consumer healthcare and electronics. In recognition of such a milestone, this roadmap on Ultrafast Optics draws together articles from some of the key opinion leaders in the field to provide a freeze-frame of the state-of-the-art, while also attempting to forecast the technical and scientific paradigms which will define the field over the next 25 years. While no roadmap can be fully comprehensive, the thirteen articles here reflect the most exciting technical opportunities presented at the current time in Ultrafast Optics. Several articles examine the future landscape for ultrafast light sources, from practical solid-state/fiber lasers and Raman microresonators to exotic attosecond extreme ultraviolet and possibly even zeptosecond x-ray pulses. Others address the control and measurement challenges, requiring radical approaches to harness nonlinear effects such as filamentation and parametric generation, coupled with the question of how to most accurately characterise the field of ultrafast pulses simultaneously in space and time. Applications of ultrafast sources in materials processing, spectroscopy and time-resolved chemistry are also discussed, highlighting the improvements in performance possible by using lasers of higher peak power and repetition rate, or by exploiting the phase stability of emerging new frequency comb sources.
NASA Astrophysics Data System (ADS)
Kalejs, J. P.
1994-01-01
Mobil Solar Energy Corporation currently practices a unique crystal growth technology for producing crystalline silicon sheet, which is then cut with lasers into wafers. The wafers are processed into solar cells and incorporated into modules for photovoltaic applications. The silicon sheet is produced using a method known as Edge-defined Film-fed growth (EFG), in the form of hollow eight-sided polygons (octagons) with 10 cm faces. These are grown to lengths of 5 meters and thickness of 300 microns, with continuous melt replenishment, in compact furnaces designed to operate at a high sheet area production area of 135 sq cm/min. The present Photovoltaic Manufacturing Technology (PVMaT) three-year program seeks to advance the manufacturing line capabilities of the Mobil Solar crystal growth and cutting technologies. If successful, these advancements will provide significant reductions in already low silicon raw material usage, improve process productivity, laser cutting throughput and yield, and so lower both individual wafer cost and the cost of module production. This report summarizes the significant technical improvements in EFG technology achieved in Phase 1 of this program. Technical results are reported for each of the three main program areas: (1) thin octagon growth (crystal growth) -- to reduce the thickness of the octagon to an interim goal of 250 microns during Phase 1, with an ultimate goal of achieving 200 micron thicknesses; (2) laser cutting -- to improve the laser cutting process, so as to produce wafers with decreased laser cutting damage at increased wafer throughput rates; and (3) process control and product specification -- to implement advanced strategies in crystal growth process control and productivity designed to increase wafer yields.
Akcay, Merve; Arslan, Hakan; Mese, Merve; Durmus, Nazlı; Capar, Ismail Davut
2017-09-01
The aim of this in vitro study was to evaluate the efficacy of different irrigation techniques including laser-activated irrigation using an erbium:yttrium-aluminum-garnet (Er:YAG) laser with a novel tip design (photon-induced photoacoustic streaming (PIPS)), Er:YAG laser with Preciso tip, sonic activation, and passive ultrasonic activation on the final irrigation solution penetration into dentinal tubules by using a laser scanning confocal microscope. In this study, 65 extracted single-rooted human mandibular premolars were instrumented up to size 40 and randomly divided into 5 groups (n = 13) based on the activation technique of the final irrigation solution as follows: conventional irrigation (control group), sonic activation, passive ultrasonic activation, Er:YAG-PIPS tip activation, and Er:YAG-Preciso tip activation. In each group, 5 mL of 5% NaOCl labeled with fluorescent dye was used during the activation as the final irrigation solution. Specimens were sectioned at 2.5 and 8 mm from the apex and then examined under a confocal microscope to calculate the dentinal tubule penetration area. Data were analyzed using two-way analysis of variance (ANOVA) and Tukey's post hoc tests (P = 0.05). Both Er:YAG laser (Preciso/PIPS) activations exhibited a significantly higher penetration area than the other groups (P < 0.05). Additionally, passive ultrasonic activation had significantly higher penetration than the sonic activation group and the control group. Statistically significant differences were also found between each root canal third (coronal > middle > apical) (P < 0.001). The results from the present study support the use of Er:YAG laser activation (Preciso/PIPS) to improve the effectiveness of the final irrigation procedure by increasing the irrigant penetration area into the dentinal tubules. The activation of the irrigant and the creation of the streaming with the Er:YAG laser have a positive effect on the irrigant penetration.
Laser pointers and aviation safety.
Nakagawara, V B; Montgomery, R W
2000-10-01
Laser pointers have been used by teachers and lecturers for years to highlight key areas on charts and screens during visual presentations. When used in a responsible manner, laser pointers are not considered to be hazardous. However, as the availability of such devices has increased, so have reports of their misuse. The Food and Drug Administration (FDA) issued a warning in December 1997 on the possibility of eye injury to children from handheld laser pointers. In October 1998, the American Academy of Ophthalmology upgraded an earlier caution to a warning, stating that laser pointers can be hazardous and should be kept away from children, after two reports of eye injuries involving young girls (age 11 and 13 yr). Of particular concern was the promotion of laser products as children's toys, such as those that can project cartoon figures and line drawings. Additionally, there have been reports involving the misuse of laser pointers (e.g., arrests made after police interpreted the red beam to be a laser-sighted weapon, spectators aiming laser lights at athletes during sporting events, cars illuminated on highways, and numerous incidents involving the illumination of aircraft). This technical note discusses physiological effects of exposure from a laser pointer, the regulation and classification of commercial laser products, and how the misuse of these pointers is a possible threat to aviation safety.
Investigation of 100 mJ all solid state end-pumped 1064 nm Q-switched laser
NASA Astrophysics Data System (ADS)
Xie, Shiyong; Wang, Caili; Liu, Hui; Bo, Yong; Xu, Zuyan
2017-11-01
High energy 1064 nm Q-switched laser output is obtained by LD vertical array end pumping Nd:YAG. Cylindrical lens are used for beam shaping of LD array for different divergence angle of fast and slow axis. Based on the theoretical simulation of fundamental mode radius using ABCD transfer matrix, the resonant cavity is optimized and curvature radius of cavity mirrors is determined. The intracavity power density is calculated according to the output laser pulse energy and transmittance of output coupling mirror is optimized under the condition that optical device is not damaged. 1064 nm laser with a maximum output of 110 mJ is generated under LD pump energy of 600 mJ, corresponding to optical conversion efficiency of 18.3%. The laser pulse width is 11 ns and divergence angle is 1.2 mrad. For saturation phenomenon of Q-switched laser output, LD temperature is adjusted to make wavelength deviate from absorption peak of Nd:YAG crystal. The parasitic oscillation, which affects the enhancement of Q-switched laser energy, can be effectively suppressed by reducing gain of pump end of laser medium, which provides an effective technical means for obtaining high energy end-pumped Q-switched laser.
Final June Revisions Rule Significant Contribution Assessment TSD
This Technical Support Document (TSD) presents quantitative assessments of the relationship between the final February revisions to the Transport Rule, the final June revisions rule, and the original analysis conducted for the final Transport Rule.
2006-05-30
implementation Final Report 4 TECHNICAL PLAN AND RESULTS Task 1: Initiate the Project Management System Two senior NGSS production management...1 Technical Plan and Results...Third the system is hosted on a handheld unit which provides the foremen with an efficient daily planning tool. The Pilot System which entails
ERIC Educational Resources Information Center
Goertz, Lori; Franklin, Barbara
This final report describes the activities and outcomes of the California Deaf-Blind Services (CDBS) program, a regionally based, family focused technical assistance and training project designed to improve services to children with deaf-blindness. The project conducted the following activities: (1) provided technical assistance to families and…
ERIC Educational Resources Information Center
New Jersey State Dept. of Education, Trenton.
This final report describes activities and accomplishments of the New Jersey Technical Assistance Project, a project to improve educational resources and support services for students with multiple sensory impairment (deaf-blindness). Activities and accomplishments are presented in a tabular format for each project goal and objective. The project…
78 FR 77563 - Technical Amendments
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-24
... NATIONAL CREDIT UNION ADMINISTRATION 12 CFR Parts 700, 701, and 704 RIN 3133-AE33 Technical Amendments AGENCY: National Credit Union Administration (NCUA). ACTION: Final rule. SUMMARY: The NCUA Board... credit unions. The technical amendments conform the regulations to a recent policy change adopted by the...
75 FR 33682 - Export Administration Regulations; Technical Amendments
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-15
...-01] RIN 0694-AE93 Export Administration Regulations; Technical Amendments AGENCY: Bureau of Industry... Bureau of Industry and Security (BIS) makes a technical amendment to the Export Administration... review of final decisions and orders issued in BIS export control administrative enforcement proceedings...
78 FR 41331 - Defense Federal Acquisition Regulation Supplement; Technical Amendments
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-10
... DEPARTMENT OF DEFENSE Defense Acquisition Regulations System 48 CFR Part 225 Defense Federal Acquisition Regulation Supplement; Technical Amendments AGENCY: Defense Acquisition Regulations System, Department of Defense (DoD). ACTION: Final rule. SUMMARY: DoD is making technical amendment to the Defense...
Leclère, F M; Duquennoy-Martinot, V; Schoofs, M; Buys, B; Mordon, S
2011-02-01
Since the first studies by Jain and Gorisch (1979), laser-assisted anastomoses have been steadily developed to a stage where clinical use is within reach. The laser-assisted vascular microanastomosis (LAMA) procedure is performed more quickly than conventional anastomosis, the surgically induced vessel damage is limited, and reduced bleeding after unclamping is observed. A Medline literature search, for the January 1979 to February 2010 period, was performed to review articles focusing on the LAMA technique. The search yielded a total of 354 publications, of which 87 were relevant: 82 were animal series and five clinical studies. Microsurgical techniques and principal characteristics of LAMA in patients are the focus of the analysis. This study discusses the technological innovations and new orientations in laser welding. The first two clinical series using the 1.9-μm diode laser appear promising. Technical innovation will most likely lead to greater ease of use of the laser handpiece in the operating room. Copyright © 2010 Elsevier Masson SAS. All rights reserved.
Diode-pumped Tunable 3 Micron Laser Sources
2000-02-21
DoD Ballistic Missile Defense Organization U.S. Army Space and Missile Defense Command SBIR Phase I Final Report AC Materials, Inc. 2721 Forsyth...pumped tunable 3 micron laser sources 6. AUTHORISI Arlete Cassanho, Hans Jenssen 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) AC Materials, Inc...impurities in the final crystal, starting materials for the crystal growth were prepared at AC Materials from optical grade barium fluoride and
Zhang, Hanwei; Zhou, Pu; Wang, Xiong; Du, Xueyuan; Xiao, Hu; Xu, Xiaojun
2015-06-29
Two kinds of hundred-watt-level random distributed feedback Raman fiber have been demonstrated. The optical efficiency can reach to as high as 84.8%. The reported power and efficiency of the random laser is the highest one as we know. We have also demonstrated that the developed random laser can be further used to pump a Ho-doped fiber laser for mid-infrared laser generation. Finally, 23 W 2050 nm laser is achieved. The presented laser can obtain high power output efficiently and conveniently and opens a new direction for high power laser sources at designed wavelength.
In space performance of the lunar orbiter laser altimeter (LOLA) laser transmitter
NASA Astrophysics Data System (ADS)
Yu, Anthony W.; Shaw, George B.; Novo-Gradac, Ann Marie; Li, Steven X.; Cavanaugh, John
2011-11-01
In this paper we present the final configuration of the space flight laser transmitter as delivered to the Lunar Orbiter Laser Altimeter (LOLA) instrument along with some in-space operation performance data. The LOLA instrument is designed to map the lunar surface and provide unprecedented data products in anticipation of future manned flight missions. The laser transmitter has been operating on orbit at the Moon continuously since July 2009 and accumulated over 1.8 billion laser shots in space. The LOLA laser transmitter design has heritage dated back to the MOLA laser transmitter launched more than 10 years ago and incorporates lessons learned from previous laser altimeter missions at NASA Goddard Space Flight Center.
Final Revisions Rule Significant Contribution Assessment TSD
This Technical Support Document (TSD) presents quantitative assessments of the relationship between final revisions to the Transport Rule and the original analysis conducted for the final Transport Rule.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anastasi, A.; Basti, A.; Bedeschi, F.
We report the test of many of the key elements of the laser-based calibration system for muon g - 2 experiment E989 at Fermilab. The test was performed at the Laboratori Nazionali di Frascati's Beam Test Facility using a 450 MeV electron beam impinging on a small subset of the final g - 2 lead-fluoride crystal calorimeter system. The calibration system was configured as planned for the E989 experiment and uses the same type of laser and most of the final optical elements. We show results regarding the calorimeter's response calibration, the maximum equivalent electron energy which can be providedmore » by the laser and the stability of the calibration system components.« less
Ärrälä, Minna; Hafiz, Hasnain; Mou, Daixiang; ...
2016-10-27
Here, we have obtained angle-resolved photoemission (ARPES) spectra from single crystals of the topological insulator material Bi 2Te 3 using tunable laser spectrometer. The spectra were collected for eleven different photon energies ranging from 5.57 to 6.70 eV for incident light polarized linearly along two different in-plane directions. Parallel first-principles, fully relativistic computations of photo-intensities were carried out using the experimental geometry within the framework of the one-step model of photoemission. Good overall accord between theory and experiment is used to gain insight into how properties of the initial and final state band structures as well as those of themore » topological surface states and their spin-textures are reflected in the laser-ARPES spectra. In conclusion, our analysis reveals that laser-ARPES is sensitive to both the initial state k z dispersion and the presence of delicate gaps in the final state electronic spectrum.« less
Development of optical sciences in Poland
NASA Astrophysics Data System (ADS)
Romaniuk, Ryszard S.
2013-10-01
Research and technical communities for optics, photonics and optoelectronics is grouped in this country in several organizations and institutions. These are: Photonics Society of Poland (PSP), Polish Committee of Optoelectronics of SEP, Photonics Section of KEiT PAN, Laser Club at WAT, and Optics Section of PTF. Each of these communities keeps slightly different specificity. PSP publishes a quarterly journal Photonics Letters of Poland, stimulates international cooperation, and organizes conferences during Industrial Fairs on Innovativeness. PKOpto SEP organizes didactic diploma competitions in optoelectronics. KEiT PAN takes patronage over national conferences in laser technology, optical fiber technology and communications, and photonics applications. SO-PTF has recently taken a decision to organize a cyclic event "Polish Optical Conference". The third edition of this conference PKO'2013 was held in Sandomierz on 30.06-04.07.2013. The conference scientific and technical topics include: quantum and nonlinear optics, photon physics, optic and technology of lasers and other sources of coherent radiation, optoelectronics, optical integrated circuits, optical fibers, medical optics, instrumental optics, optical spectroscopy, optical metrology, new optical materials, applications of optics, teaching in optics. This paper reviews chosen works presented during the III Polish Optical Conference (PKO'2013), representing the research efforts at different national institutions.
Three-dimensional imaging of porous media using confocal laser scanning microscopy.
Shah, S M; Crawshaw, J P; Boek, E S
2017-02-01
In the last decade, imaging techniques capable of reconstructing three-dimensional (3-D) pore-scale model have played a pivotal role in the study of fluid flow through complex porous media. In this study, we present advances in the application of confocal laser scanning microscopy (CLSM) to image, reconstruct and characterize complex porous geological materials with hydrocarbon reservoir and CO 2 storage potential. CLSM has a unique capability of producing 3-D thin optical sections of a material, with a wide field of view and submicron resolution in the lateral and axial planes. However, CLSM is limited in the depth (z-dimension) that can be imaged in porous materials. In this study, we introduce a 'grind and slice' technique to overcome this limitation. We discuss the practical and technical aspects of the confocal imaging technique with application to complex rock samples including Mt. Gambier and Ketton carbonates. We then describe the complete workflow of image processing to filtering and segmenting the raw 3-D confocal volumetric data into pores and grains. Finally, we use the resulting 3-D pore-scale binarized confocal data obtained to quantitatively determine petrophysical pore-scale properties such as total porosity, macro- and microporosity and single-phase permeability using lattice Boltzmann (LB) simulations, validated by experiments. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.
NASA Astrophysics Data System (ADS)
Feehan, James S.; Price, Jonathan H. V.; Butcher, Thomas J.; Brocklesby, William S.; Frey, Jeremy G.; Richardson, David J.
2017-01-01
The development of an Yb3+-fiber-based chirped-pulse amplification system and the performance in the generation of extreme ultraviolet (EUV) radiation by high-harmonic generation is reported. The fiber laser produced 100 μJ, 350 fs output pulses with diffraction-limited beam quality at a repetition rate of 16.7 kHz. The system used commercial single-mode, polarization maintaining fiber technology. This included a 40 μm core, easily packaged, bendable final amplifier fiber in order to enable a compact system, to reduce cost, and provide reliable and environmentally stable long-term performance. The system enabled the generation of 0.4 μW of EUV at wavelengths between 27 and 80 nm with a peak at 45 nm using xenon gas. The EUV flux of 1011 photons per second for a driving field power of 1.67 W represents state-of-the-art generation efficiency for single-fiber amplifier CPA systems, corresponding to a maximum calculated energy conversion efficiency of 2.4 × 10-7 from the infrared to the EUV. The potential for high average power operation at increased repetition rates and further suggested technical improvements are discussed. Future applications could include coherent diffractive imaging in the EUV, and high-harmonic spectroscopy.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jannson, T.
1993-03-01
During the last two decades, there have been dramatic improvements in the development of optical sources. Examples of this development range from semiconductor laser diodes to free electron beam lasers and synchrotron radiation. Before these developments, standards for the measurement of basic optical parameters (quantities) were less demanding. Now, however, there is a fundamental need for new, reliable methods for providing fast quantitative results for a very broad variety of optical systems and sources. This is particularly true for partially coherent optical beams, since all optical sources are either fully or partially spatially coherent (including Lambertian sources). Until now, theremore » has been no satisfactory solution to this problem. During the last two decades, however, the foundations of physical radiometry have been developed by Walther, Wolf and co-workers. By integrating physical optics, statistical optics and conventional radiometry, this body of work provides necessary tools for the evaluation of radiometric quantities for partially coherent optical beams propagating through optical systems. In this program, Physical Optics Corporation (POC) demonstrated the viability of such a radiometric approach for the specific case of generalized energy concentrators called Liouville transformers. We believe that this radiometric approach is necessary to fully characterize any type of optical system since it takes into account the partial coherence of radiation. 90 refs., 57 figs., 4 tabs.« less
Comparing the effectiveness of laser vs. conventional endoforehead lifting.
Chang, Cheng-Jen; Yu, De-Yi; Chang, Shu-Ying; Hsiao, Yen-Chang
2018-04-01
The objective of this study was to compare the efficacy and safety of laser versus conventional endoforehead lifting. Over a period of 12 years (January 2000-January 2012), a total of 110 patients with hyperactive muscles over the frontal region have been collected for a retrospective study. The SurgiLase 150XJ CO 2 laser system, in conjunction with the flexible FIBERLASE, was used. The endoscope was 4 mm in diameter with an angle of 30°. The primary efficacy measurement was the assessment of the final outcome for using laser vs. conventional methods. Both groups were observed at three weeks, six weeks and six months after surgery. The most common complication in early convalescence (three weeks) was swelling. This was followed by local paraesthesia, ecchymosis, localized hematomas and scar with alopecia. All these problems disappeared completely after the 6-month study period. Based on a chi-square analysis, there were clinically and statistically significant differences favouring the laser endoforehead surgery in the operative time, early and late complications. All patients achieved significant improvement after both laser and conventional endoforehead surgery in the final outcome. However, the early and late complications indicated a greater difference in the laser group.
Cho, Yuichiro; Horiuchi, Misa; Shibasaki, Kazuo; Kameda, Shingo; Sugita, Seiji
2017-08-01
In situ radiogenic isotope measurements to obtain the absolute age of geologic events on planets are of great scientific value. In particular, K-Ar isochrons are useful because of their relatively high technical readiness and high accuracy. Because this isochron method involves spot-by-spot K measurements using laser-induced breakdown spectroscopy (LIBS) and simultaneous Ar measurements with mass spectrometry, LIBS measurements are conducted under a high vacuum condition in which emission intensity decreases significantly. Furthermore, using a laser power used in previous planetary missions is preferable to examine the technical feasibility of this approach. However, there have been few LIBS measurements for K under such conditions. In this study, we measured K contents in rock samples using 30 mJ and 15 mJ energy lasers under a vacuum condition (10 -3 Pa) to assess the feasibility of in situ K-Ar dating with lasers comparable to those used in NASA's Curiosity and Mars 2020 missions. We obtained various calibration curves for K using internal normalization with the oxygen line at 777 nm and continuum emission from the laser-induced plasma. Experimental results indicate that when K 2 O < 1.1 wt%, a calibration curve using the intensity of the K emission line at 769 nm normalized with that of the oxygen line yields the best results for the 30 mJ laser energy, with a detection limit of 88 ppm and 20% of error at 2400 ppm of K 2 O. Futhermore, the calibration curve based on the K 769 nm line intensity normalized with continuum emission yielded the best result for the 15 mJ laser, giving a detection limit of 140 ppm and 20% error at 3400 ppm K 2 O. Error assessments using obtained calibration models indicate that a 4 Ga rock with 3000 ppm K 2 O would be measured with 8% (30 mJ) and 10% (15 mJ) of precision in age when combined with mass spectrometry of 40 Ar with 10% of uncertainty. These results strongly suggest that high precision in situ isochron K-Ar dating is feasible with a laser used in previous and upcoming Mars rover missions.
75 FR 15342 - Advisory Committees; Technical Amendment
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-29
... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 14 [Docket No. FDA-2010-N-0001] Advisory Committees; Technical Amendment Agency: Food and Drug Administration, HHS. ACTION: Final rule; technical amendment. SUMMARY: The Food and Drug Administration (FDA) is amending its...
Surface treatment with linearly polarized laser beam at oblique incidence
NASA Astrophysics Data System (ADS)
Gutu, I.; Petre, C.; Mihailescu, I. N.; Taca, M.; Alexandrescu, E.; Ivanov, I.
2002-07-01
An effective method for surface heat treatment with 10.6 μm linear polarized laser beam at oblique incidence is reported. A circular focused laser spot on the workpiece surface, simultaneously with 2.2-4 times increasing of the absorption are obtained in the 70-80° range of the incidence angle. The main element of the experimental setup is the astigmatic focusing head which focalize the laser beam into an elliptical spot of ellipticity ɛ>3 at normal incidence. At a proper incidence angle (obtained by the focusing head tilting) the focused laser spot on the work piece surface gets a circular form and p-state of polarization is achieved. We performed laser heat treatment (transformation hardening, surface remelting) of the uncoated surface, as well as the alloying and cladding processes by powder injection. An enhancement of the processing efficiency was obtained; in this way the investment and operation costs for surface treatment with CO 2 laser can be significantly reduced. Several technical advantages concerning the pollution of the focusing optical components, powder jet flowing and reflected radiation by the work piece surface are obtained.
NASA Astrophysics Data System (ADS)
Hegelich, Bjorn M.; Arefiev, Alexey; Ditmire, Todd; Donovan, Michael E.; Dyer, Gillis; Gaul, Erhard; Labun, Lance; Luedtke, Scott; Martinez, Mikael; McCarry, Edward; Stark, David; Pomerantz, Ishay; Tiwari, Ganesh; Toncian, Toma
2015-11-01
Advances in laser-based hadron generation, especially with respect to particle energy, as well as reaching the new regime of radiation dominated plasmas and non-linear QED, require laser fields of Petavolts per meter that preferably interact with very high density, overcritical plasmas. To achieve these conditions we are upgrading the Texas Petawatt Laser both respect to on-target laser intensity and laser-contrast, aiming to reach intensities of ~ 5x1022 W/cm2 and pulse contrast parameters allowing the interaction with overcritical, yet ultrathin, sub-micron targets. We will report on the planned experiments aimed at ion acceleration, neutron generation and the first experimental measurement of radiation reactions to motivate the chosen upgrade parameters. We will further report on the technical changes to the laser and present first measurements of the achieved intensity and contrast parameters. This work was supported by NNSA cooperative agreement DE-NA0002008, the Defense Advanced Research Projects Agency's PULSE program (12-63-PULSE-FP014), the Air Force Office of Scientific Research (FA9550-14-1-0045) and the National Institute of Health SBIR.
Atraumatic laser treatment for laryngeal papillomatosis
NASA Astrophysics Data System (ADS)
McMillan, Kathleen; Pankratov, Michail M.; Wang, Zhi; Bottrill, Ian; Rebeiz, Elie E.; Shapshay, Stanley M.
1994-09-01
Ten to fifteen thousand new cases of recurrent respiratory papillomatosis (RRP) are diagnosed each year in the United States. RRP is caused by the human papillomavirus (HPV) and is characterized by recurrent, non-malignant, proliferative lesions of the larynx. Patients with RRP undergo numerous microsurgical procedures to remove laryngeal papilloma threatening airway patency and interfering with phonation. The standard surgical technique involves CO2 laser vaporization of laryngeal epithelium affected by the lesions, and requires general anesthesia. The pulsed dye laser operating at 585 nm has previously been demonstrated to be effective in clearing HPV lesions of the skin (verrucae). For treatment of RRP, the fiber- compatible pulsed dye laser radiation may be delivered under local anesthesia using a flexible intranasal laryngoscope. Potential advantages of the pulsed dye laser treatment over CO2 laser surgery include (1) reduced morbidity, especially a lower risk of laryngeal scarring; (2) lower cost; (3) reduced technical difficulty; and (4) reduced risk of viral dissemination or transmission. In vivo studies are underway to determine the effect of pulsed dye laser radiation on normal canine laryngeal tissue.
Innovative Facet Passivation for High-Brightness Laser Diodes
2016-02-05
and anti-reflection (AR) coatings are deposited after cleaving. Edge- emitting laser diodes emit very high optical powers from small emission areas, as...SECURITY CLASSIFICATION OF: The objective of this effort is to increase the power of low fill-factor (20%) laser diode (LD) bars from the present...2012 16-Nov-2015 Approved for Public Release; Distribution Unlimited Final Report: Innovative Facet Passivation for High-Brightness Laser Diodes The
High-power laser diodes at various wavelengths
DOE Office of Scientific and Technical Information (OSTI.GOV)
Emanuel, M.A.
High power laser diodes at various wavelengths are described. First, performance and reliability of an optimized large transverse mode diode structure at 808 and 941 nm are presented. Next, data are presented on a 9.5 kW peak power array at 900 nm having a narrow emission bandwidth suitable for pumping Yb:S-FAP laser materials. Finally, results on a fiber-coupled laser diode array at {approx}730 nm are presented.
2012 Technical Corrections Fact Sheet
Final Rule: 2012 Technical Corrections, Clarifying and Other Amendments to theGreenhouse Gas Reporting Rule, and Confidentiality Determinations for Certain DataElements of the Fluorinated Gas Source Category
Design of sensors for microcirculation investigation in pharyngeal mucosa
NASA Astrophysics Data System (ADS)
Mareew, Gleb O.; Mareew, Oleg V.; Fedosov, Ivan V.; Tuchin, Valery V.
2004-08-01
Sensors designed for research of blood microcirculation in pharyngeal mucosa by a laser Doppler flowmetry, are described and considered in view of anatomic and physiological features of objects of research. Two designs of sensors for laser Doppler flowmetry are described - non-contact and contact. The results of and clinical testing at norm and different pathologies of pharynx of on calibration of sensors, and also their comparative technical characteristics and materials of clinical researches of microcirculation are resulted at norm and at a various pathology.
Current and emerging laser sensors for greenhouse gas sensing and leak detection
NASA Astrophysics Data System (ADS)
Frish, Michael B.
2014-05-01
To reduce atmospheric accumulation of the greenhouse gases methane and carbon dioxide, networks of continuously operating sensors that monitor and map their sources are desirable. In this paper, we discuss advances in laser-based open-path leak detectors, as well as technical and economic challenges inhibiting widespread sensor deployment for "ubiquitous monitoring". We describe permanently-installed, wireless, solar-powered sensors that overcome previous installation and maintenance difficulties while providing autonomous real-time leak reporting without false alarms.
Semiconductor Laser Diode Pumps for Inertial Fusion Energy Lasers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deri, R J
2011-01-03
Solid-state lasers have been demonstrated as attractive drivers for inertial confinement fusion on the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) and at the Omega Facility at the Laboratory for Laser Energetics (LLE) in Rochester, NY. For power plant applications, these lasers must be pumped by semiconductor diode lasers to achieve the required laser system efficiency, repetition rate, and lifetime. Inertial fusion energy (IFE) power plants will require approximately 40-to-80 GW of peak pump power, and must operate efficiently and with high system availability for decades. These considerations lead to requirements on the efficiency, price, and productionmore » capacity of the semiconductor pump sources. This document provides a brief summary of these requirements, and how they can be met by a natural evolution of the current semiconductor laser industry. The detailed technical requirements described in this document flow down from a laser ampl9ifier design described elsewhere. In brief, laser amplifiers comprising multiple Nd:glass gain slabs are face-pumped by two planar diode arrays, each delivering 30 to 40 MW of peak power at 872 nm during a {approx} 200 {micro}s quasi-CW (QCW) pulse with a repetition rate in the range of 10 to 20 Hz. The baseline design of the diode array employs a 2D mosaic of submodules to facilitate manufacturing. As a baseline, they envision that each submodule is an array of vertically stacked, 1 cm wide, edge-emitting diode bars, an industry standard form factor. These stacks are mounted on a common backplane providing cooling and current drive. Stacks are conductively cooled to the backplane, to minimize both diode package cost and the number of fluid interconnects for improved reliability. While the baseline assessment in this document is based on edge-emitting devices, the amplifier design does not preclude future use of surface emitting diodes, which may offer appreciable future cost reductions and increased reliability. The high-level requirements on the semiconductor lasers involve reliability, price points on a price-per-Watt basis, and a set of technical requirements. The technical requirements for the amplifier design in reference 1 are discussed in detail and are summarized in Table 1. These values are still subject to changes as the overall laser system continues to be optimized. Since pump costs can be a significant fraction of the overall laser system cost, it is important to achieve sufficiently low price points for these components. At this time, the price target for tenth-of-akind IFE plant is $0.007/Watt for packaged devices. At this target level, the pumps account for approximately one third of the laser cost. The pump lasers should last for the life of the power plant, leading to a target component lifetime requirement of roughly 14 Ghosts, corresponding to a 30 year plant life and 15 Hz repetition rate. An attractive path forward involes pump operation at high output power levels, on a Watts-per-bar (Watts/chip) basis. This reduces the cost of pump power (price-per-Watt), since to first order the unit price does not increase with power/bar. The industry has seen a continual improvement in power output, with current 1 cm-wide bars emitting up to 500 W QCW (quasi-continuous wave). Increased power/bar also facilitates achieving high irradiance in the array plane. On the other hand, increased power implies greater heat loads and (possibly) higher current drive, which will require increased attention to thermal management and parasitic series resistance. Diode chips containing multiple p-n junctions and quantum wells (also called nanostack structures) may provide an additional approach to reduce the peak current.« less
Alsaad, Salman M S; Ross, E Victor; Mishra, Vineet; Miller, Lee
2014-12-01
To determine the safety and efficacy of a 50 ns Q switched Nd YAG laser vs. a 5 ns Q switched Nd YAG laser for clearance of melasma. To compare subject satisfaction, efficacy, and comfort level between the two lasers. This is a prospective, randomized split face clinical study. The study was approved by the Scripps IRB. Ten healthy female subjects with moderate to severe melasma were enrolled. Each subject had three laser treatments one month apart. Patients were followed up approximately 1 month, 3 months, and 6 months after the final laser treatment. A treatment session consisted of a microdermabrasion, 1064 nm QS laser, and topicals. Subjects were asked to rate treatment pain based on a numerical scale range 0-10 (0 = no pain and 10 = worst pain). A melasma area and severity index (MASI) grading system was applied. Also, melanin measurements were acquired by a reflectance spectrophotometer. Side effects were documented during the study including post treatment erythema. Eight patients completed the study. Subjects showed improvement on both sides of the face. From baseline to 1 month post the final laser treatment, the average MASI scores showed a 16% reduction for the 50 ns QS 1064 nm laser vs. a 27% reduction for the 5 ns QS 1064 nm laser (both significant versus baseline pigment, P < 0.05). This difference in MASI scores between the two lasers was not statistically significant (P = 0.87930). Laser treatments displayed mild erythema that resolved after one day. The melanin meter measurements showed a reduction in pigment readings on both sides. Three months after the final treatment there was some relapse in the melasma, as the mean pigment reduction fell to 12% for the 50 ns laser and 11% for the 5 ns laser. By 3 months pigment reduction was not statistically significant for either laser, and no significant differences in pigment reduction were noted between the two pulse durations. There was a statistically significant difference (P < 0.05) in pain scores reported by the subjects (scale 0-10), the mean pain score for 50 ns QS 1064 nm laser was 1.2 and for the 5 ns QS 2.9 the score was 2.9. In this study, we showed that a combination of microdermabrasion, QS1064 nm laser, and topicals decreased the MASI and meter scores without clinically significant side effects. Moreover, the longer pulsed Q switched 1064 nm laser i.e. (50 ns) was associated with less pain than its shorter pulse width counterpart. © 2014 Wiley Periodicals, Inc.
Spectroscopic and laser characterization of emerald. Final report, April 1983-April 1986
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lai, S.T.; Chai, B.H.
1986-08-01
The spectroscopic characteristics and laser properties of emerald were investigated. The laser measurements showed that the emerald-laser tuning range was 720-842 nm and exhibited a high gain and high efficiency in the 760-790 nm range. Under a crystal growth development program, the laser loss was reduced from 11%/cm to 0.4%/cm. The limiting factor in the laser efficiency is the excited-state absorption (ESA). The ESA was measured by two methods: a laser-pumped single-pass gain method, which is generally applicable to all tunable laser materials, and a laser-pumped laser method. A 76% laser quantum yield was obtained in high-optical-quality emerald. The maximummore » yield is estimated to be 83%, based on the ESA measurements.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
de Boer, Gijs; Lawrence, Dale; Palo, Scott
2017-03-29
This final technical report details activities undertaken as part of the referenced project. Included is information on the preparation of aircraft for deployment to Alaska, summaries of the three deployments covered under this project, and a brief description of the dataset and science directions pursued. Additionally, we provide information on lessons learned, publications, and presentations resulting from this work.
ERIC Educational Resources Information Center
Gardner, David C.; And Others
Volume 1 of the final report on Project HIRE reports the design, development, field-testing, and refining of self-instructional packages to teach entry level technical vocabulary to learning handicapped students mainstreamed in vocational programs. Volume 2, a management handbook, reports the methods and findings concerning development of…
Joint Technical Architecture for Robotic Systems (JTARS)-Final Report
NASA Technical Reports Server (NTRS)
Bradley, Arthur T.; Holloway, Sidney E., III
2006-01-01
This document represents the final report for the Joint Technical Architecture for Robotic Systems (JTARS) project, funded by the Office of Exploration as part of the Intramural Call for Proposals of 2005. The project was prematurely terminated, without review, as part of an agency-wide realignment towards the development of a Crew Exploration Vehicle (CEV) and meeting the near-term goals of lunar exploration.
ERIC Educational Resources Information Center
Bobronnikov, Ellen; Rhodes, Hilary; Bradley, Cay
2010-01-01
This final report culminates the evaluation and technical assistance provided for the U.S. Department of Education's Mathematics and Science Partnership (MSP) Program and its projects since 2005. As part of this support, Abt Associates looked across the portfolio of projects funded by the MSP program to draw lessons on best practices. This…
Pacific Educational Computer Network Study. Final Report.
ERIC Educational Resources Information Center
Hawaii Univ., Honolulu. ALOHA System.
The Pacific Educational Computer Network Feasibility Study examined technical and non-technical aspects of the formation of an international Pacific Area computer network for higher education. The technical study covered the assessment of the feasibility of a packet-switched satellite and radio ground distribution network for data transmission…
Selection of Electronic Resources.
ERIC Educational Resources Information Center
Weathers, Barbara
1998-01-01
Discusses the impact of electronic resources on collection development; selection of CD-ROMs, (platform, speed, video and sound, networking capability, installation and maintenance); selection of laser disks; and Internet evaluation (accuracy of content, authority, objectivity, currency, technical characteristics). Lists Web sites for evaluating…
1987-09-01
workstation (ADMS) and associated literature and laser printouts * Athol Fodon and Jim Tillinghast-- Palantir Corporation--for their analysis...TILL.CcI’:i1iCO technical ocumentaton. An \\obiective of :his research -,as toaave .:o:m . This author specillcaiY ’commi-issioned’ the Palantir Corporation...formats, letter size, illustrations, pictures, fold-out pages and relative familiarity with fleet users. The Palantir Corporation analyzed and compared
Fort Monmouth Technical Disclosure Bulletin. Volume 1, Number 1.
1982-12-01
laser A may be placed between two plates in an evacuated area, and a space charge cloud caused by a multipactor i:.y be r.iade to niove between the...Radiation Detection Uodem Multipactor FuIP Ct] 1 AfTRACT (CAeM ree e, dl N nmeW -V md identl by block numbe) The Technical Disclosure Bulletin is...can be used with any digital signal containing regularly spaced synchronization bits or characters or else additional synchronization bits can be added
Song, Shu-Tao; Cui, Lan; Yang, Jing; Du, Xi-Wen
2015-01-28
As a promising material for photoelectrical application, MoS2 has attracted extensive attention on its facile synthesis and unique properties. Herein, we explored a novel strategy of laser ablation to synthesize MoS2 fullerene-like nanoparticles (FL-NPs) with stable photoresponse under high temperature. Specifically, we employed a millisecond pulsed laser to ablate the molybdenum target in dimethyl trisulfide gas, and as a result, the molybdenum nanodroplets were ejected from the target and interacted with the highly reactive ambient gas to produce MoS2 FL-NPs. In contrast, the laser ablation in liquid could only produce core-shell nanoparticles. The crucial factors for controlling final nanostructures were found to be laser intensity, cooling rate, and gas reactivity. Finally, the MoS2 FL-NPs were assembled into a simple photoresponse device which exhibited excellent thermal stability, indicating their great potentialities for high-temperature photoelectrical applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Douberly, Gary Elliott
The objective of our experimental research program is to isolate and stabilize transient intermediates and products of prototype combustion reactions. This will be accomplished by Helium Nanodroplet Isolation, a novel technique where liquid helium droplets freeze out high energy metastable configurations of a reacting system, permitting infrared spectroscopic characterizations of products and intermediates that result from hydrocarbon radical reactions with molecular oxygen and other small molecules relevant to combustion environments. The low temperature (0.4 K) and rapid cooling associated with He droplets provides a perfectly suited medium to isolate and probe a broad range of molecular radical and carbene systemsmore » important to combustion chemistry. The sequential addition of molecular species to He droplets often leads to the stabilization of high-energy, metastable cluster configurations that represent regions of the potential energy surface far from the global minimum. Single and double resonance IR laser spectroscopy techniques, along with Stark and Zeeman capabilities, are being used to probe the structural and dynamical properties of these systems.« less
Laboratory and Space Plasma Studies
NASA Astrophysics Data System (ADS)
Hyman, Ellis
1996-08-01
The work performed by Science Applications International Corporation (SAIC), encompasses a wide range of topics in experimental, computational, and analytical laboratory and space plasma physics. The accomplishments described in this report have been in support of the programs of the Laser Plasma Branch (Code 6730) and other segments of the Plasma Physics Division at the Naval Research Laboratory (NRL) and cover the period 27 September 1993 to August 1, 1996. SAIC's efforts have been supported by sub-contracts or consulting agreements with Pulse Sciences, Inc., Clark Richardson, and Biskup Consulting Engineers, Pharos Technical Enterprises, Plex Corporation, Cornell University, Stevens Institute of Technology, the University of Connecticut, Plasma Materials and Technologies, Inc., and GaSonics International, Inc. In the following discussions section we will describe each of the topics investigated and the results obtained. Much of the research work has resulted in journal publications and NRL Memorandum Reports in which the investigation is described in detail. These reports are included as Appendices to this Final Report.
NASA Technical Reports Server (NTRS)
Collis, R. T. H.
1969-01-01
Lidar is an optical radar technique employing laser energy. Variations in signal intensity as a function of range provide information on atmospheric constituents, even when these are too tenuous to be normally visible. The theoretical and technical basis of the technique is described and typical values of the atmospheric optical parameters given. The significance of these parameters to atmospheric and meteorological problems is discussed. While the basic technique can provide valuable information about clouds and other material in the atmosphere, it is not possible to determine particle size and number concentrations precisely. There are also inherent difficulties in evaluating lidar observations. Nevertheless, lidar can provide much useful information as is shown by illustrations. These include lidar observations of: cirrus cloud, showing mountain wave motions; stratification in clear air due to the thermal profile near the ground; determinations of low cloud and visibility along an air-field approach path; and finally the motion and internal structure of clouds of tracer materials (insecticide spray and explosion-caused dust) which demonstrate the use of lidar for studying transport and diffusion processes.
NASA Astrophysics Data System (ADS)
Gref, Orman; Weizman, Moshe; Rhein, Holger; Gabriel, Onno; Gernert, Ulrich; Schlatmann, Rutger; Boit, Christian; Friedrich, Felice
2016-06-01
A conductive atomic force microscope is used to study the local topography and conductivity of laser-fired aluminum contacts on KOH-structured multicrystalline silicon surfaces. A significant increase in conductivity is observed in the laser-affected area. The area size and spatial uniformity of this enhanced conductivity depends on the laser energy fluence. The laser-affected area shows three ring-shaped regimes of different conductance depending on the local aluminum and oxygen concentration. Finally, it was found that the topographic surface structure determined by the silicon grain orientation does not significantly affect the laser-firing process.
Electro-optic harmonic conversion to switch a laser beam out of a cavity
Haas, R.A.; Henesian, M.A.
1984-10-19
The present invention relates to switching laser beams out of laser cavities, and more particularly, it relates to the use of generating harmonics of the laser beam to accomplish the switching. When laser light is generatd in a laser cavity the problem arises of how to switch the laser light out of the cavity in order to make use of the resulting laser beam in a well known multitude of ways. These uses include range finding, communication, remote sensing, medical surgery, laser fusion applications and many more. The switch-out problem becomes more difficult as the size of the laser aperture grows such as in laser fusion applications. The final amplifier stages of the Nova and Novette lasers at Lawrence Livermore National Laboratory are 46 centimeters with the laser beam expanded to 74 centimeters thereafter. Larger aperture lasers are planned.
Advanced optic fabrication using ultrafast laser radiation
NASA Astrophysics Data System (ADS)
Taylor, Lauren L.; Qiao, Jun; Qiao, Jie
2016-03-01
Advanced fabrication and finishing techniques are desired for freeform optics and integrated photonics. Methods including grinding, polishing and magnetorheological finishing used for final figuring and polishing of such optics are time consuming, expensive, and may be unsuitable for complex surface features while common photonics fabrication techniques often limit devices to planar geometries. Laser processing has been investigated as an alternative method for optic forming, surface polishing, structure writing, and welding, as direct tuning of laser parameters and flexible beam delivery are advantageous for complex freeform or photonics elements and material-specific processing. Continuous wave and pulsed laser radiation down to the nanosecond regime have been implemented to achieve nanoscale surface finishes through localized material melting, but the temporal extent of the laser-material interaction often results in the formation of a sub-surface heat affected zone. The temporal brevity of ultrafast laser radiation can allow for the direct vaporization of rough surface asperities with minimal melting, offering the potential for smooth, final surface quality with negligible heat affected material. High intensities achieved in focused ultrafast laser radiation can easily induce phase changes in the bulk of materials for processing applications. We have experimentally tested the effectiveness of ultrafast laser radiation as an alternative laser source for surface processing of monocrystalline silicon. Simulation of material heating associated with ultrafast laser-material interaction has been performed and used to investigate optimized processing parameters including repetition rate. The parameter optimization process and results of experimental processing will be presented.
Department of Defense high power laser program guidance
NASA Astrophysics Data System (ADS)
Muller, Clifford H.
1994-06-01
The DoD investment of nominally $200 million per year is focused on four high power laser (HPL) concepts: Space-Based Laser (SBL), a Ballistic Missile Defense Organization effort that addresses boost-phase intercept for Theater Missile Defense and National Missile Defense; Airborne Laser (ABL), an Air Force effort that addresses boost-phase intercept for Theater Missile Defense; Ground-Based Laser (GBL), an Air Force effort addressing space control; and Anti-Ship Missile Defense (ASMD), a Navy effort addressing ship-based defense. Each organization is also supporting technology development with the goal of achieving less expensive, brighter, and lighter high power laser systems. These activities represent the building blocks of the DoD program to exploit the compelling characteristics of the high power laser. Even though DoD's HPL program are focused and moderately strong, additional emphasis in a few technical areas could help reduce risk in these programs. In addition, a number of options are available for continuing to use the High-Energy Laser System Test Facility (HELSTF) at White Sands Missile Range. This report provides a brief overview and guidance for the five efforts which comprise the DoD HPL program (SBL, ABL, GBL, ASMD, HELSTF).
New 445 nm blue laser for laryngeal surgery combines photoangiolytic and cutting properties.
Hess, Markus M; Fleischer, Susanne; Ernstberger, Marcel
2018-06-01
Photoangiolytic lasers have broadened the surgical armamentarium for many phonosurgical interventions. However, the pulse dye laser and potassium titanyl phosphate (KTP) laser have technical drawbacks and a smaller spectrum of indications. The new 445 nm wavelength laser, the so-called 'blue laser', proves to show tissue effects comparable to the KTP laser and is also capable of treating subepithelial vessels due to its photoangiolytic properties, it can coagulate and carbonize at higher energy levels, and can be used via glass fibers in non-contact and contact mode for in-office procedures. In contrast to the KTP, the new 445 nm laser can also be used as a cutting laser, thus combining very much wanted properties of diode or CO2 lasers with photoangiolytic lasers. Further advantages of the new laser are the; (1) portability of the shoe box sized, shock-proof laser machine for in-office and operating room usage, (2) the selection of pulse rates from continuous wave (cw) to less than a millisecond, (3) stronger tissue effects compared to KTP with similar energy and pulse settings, (4) far better cutting properties than the KTP, and thus (5) more possibilities for usage in laryngology as well as in other fields or surgery. We demonstrate the feasibility of the 445 nm laser in several laboratory experiments and show clinical cases where photoangiolysis and cutting was possible. However, this is a preliminary report and further systematic studies in greater numbers are warranted.
The causes of high power diode laser brazed seams fractures of dissimilar materials
NASA Astrophysics Data System (ADS)
Adamiak, Marcin; Czupryński, Artur; Janicki, Damian; Górka, Jacek
2016-12-01
Presented in this article are the results of experiments carried out to determine the causes of braze cracking of dissimilar materials brazed with a ROFIN DL 020 high power diode laser with the use of additional powdered EN AW-1070A aluminium alloy to bond thin aluminium sheets with soft, low alloy DC04+ZE75/75 steel plate which was electrolytically coated with zinc on both sides. Presented are the results of metallographic, macroscopic, microscopic, diffractometric phase analyses of the weld joints. Metallurgical problems arising during processing as well as suggestions regarding technical aspects of laser brazing dissimilar materials in regards to their physical characteristics and chemical composition are explored.
Wavelength-dependence of double optical gating for attosecond pulse generation
NASA Astrophysics Data System (ADS)
Tian, Jia; Li, Min; Yu, Ji-Zhou; Deng, Yong-Kai; Liu, Yun-Quan
2014-10-01
Both polarization gating (PG) and double optical gating (DOG) are productive methods to generate single attosecond (as) pulses. In this paper, considering the ground-state depletion effect, we investigate the wavelength-dependence of the DOG method in order to optimize the generation of single attosecond pulses for the future application. By calculating the ionization probabilities of the leading edge of the pulse at different driving laser wavelengths, we obtain the upper limit of duration for the driving laser pulse for the DOG setup. We find that the upper limit duration increases with the increase of laser wavelength. We further describe the technical method of choosing and calculating the thickness values of optical components for the DOG setup.
NASA Technical Reports Server (NTRS)
Billman, K. W.
1978-01-01
Concepts for space-based conversion of space radiation energy into useful energy for man's needs are developed and supported by studies of costs, material and size requirements, efficiency, and available technology. Besides the more studied solar power satellite system using microwave transmission, a number of alternative space energy concepts are considered. Topics covered include orbiting mirrors for terrestrial energy supply, energy conversion at a lunar polar site, ultralightweight structures for space power, radiatively sustained cesium plasmas for solar electric conversion, solar pumped CW CO2 laser, superelastic laser energy conversion, laser-enhanced dynamics in molecular rate processes, and electron beams in space for energy storage.
1993-02-04
memories is presented. (p. 400) JWC2 Pairwlse visible to UV up- tions. Periodic domain-inverted structure has conversion In Ho=÷ and Tm’" doped potential...Sydney. Nd:W. aM5itoL 40 1A 18 led &: 400 1C ID •:•• •e,,,- • ,, Figure 1; Geometries for solid collectors with 1, 2 or 3 pump sources. Figure 2...Although the output efficiencies of early devices were quite low, resonant enhancement of the signal input inside the laser cavity has recently led to
Implementation status of the extreme light infrastructure - nuclear physics (ELI-NP) project
NASA Astrophysics Data System (ADS)
Gales, S.; Zamfir, N. V.
2015-02-01
The Project Extreme Light Infrastructure (ELI) is part of the European Strategic Forum for Research Infrastructures (ESFRI) Roadmap. ELI will be built as a network of three complementary pillars at the frontier of laser technologies. The ELI-NP pillar (NP for Nuclear Physics) is under construction near Bucharest (Romania) and will develop a scientific program using two 10 PW lasers and a Compton back-scattering high-brilliance and intense gamma beam, a marriage of laser and accelerator technology at the frontier of knowledge. In the present paper, the technical description of the facility, the present status of the project as well as the science, applications and future perspectives will be discussed.
Pulsed infrared difference frequency generation in CdGeAs.sub.2
Piltch, Martin S.; Rink, John P.; Tallman, Charles R.
1977-03-08
The disclosure relates to a laser apparatus for generating a line-tunable pulsed infrared difference frequency output. The apparatus comprises a CO.sub.2 laser which produces a first frequency, a CO laser which produces a second frequency and a mixer for combining the output of the CO.sub.2 and CO lasers so as to produce a final output comprising a difference frequency from the first and second frequency outputs.
Pulsed infrared difference frequency generation in CdGeAs/sub 2/
Piltch, M.S.; Rink, J.P.; Tallman, C.R.
1975-11-26
A laser apparatus for generating a line-tunable pulsed infrared difference frequency output is described. The apparatus comprises a CO/sub 2/ laser which produces a first frequency, a CO laser which produces a second frequency, and a mixer for combining the output of the CO/sub 2/ and CO lasers so as to produce a final output comprising a difference frequency from the first and second frequency outputs.
Community College Technical Mathematics Project. Final Report.
ERIC Educational Resources Information Center
Self, Samuel L.
The purpose of the research project was to develop an applied or technical mathematics curriculum which would meet the needs of vocational-technical students at the community college level. The research project was divided into three distinct phases: Identifying the mathematical concepts requisite for job-entry competencies in each of the…
7 CFR 614.10 - Appeals before the Farm Service Agency county committee.
Code of Federal Regulations, 2010 CFR
2010-01-01
... section are completed, provide the FSA county committee with a written technical determination in the form... part 780, a participant may appeal a final technical determination or a program decision to the FSA... appeal requests review of the technical determination by the applicable State Conservationist prior to...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-08
... intervention and preschool service providers with data on their qualifications, certification, and preparation... Priority; Technical Assistance on State Data Collection, Analysis, and Reporting--National IDEA Technical Assistance Center on Early Childhood Longitudinal Data Systems; Rule #0;#0;Federal Register / Vol. 77, No...
77 FR 18716 - Transportation Security Administration Postal Zip Code Change; Technical Amendment
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-28
... organizational changes and it has no substantive effect on the public. DATES: Effective March 28, 2012. FOR... No. 1572-9] Transportation Security Administration Postal Zip Code Change; Technical Amendment AGENCY: Transportation Security Administration, DHS. ACTION: Final rule. SUMMARY: This rule is a technical change to...
The study of laser beam riding guided system based on 980nm diode laser
NASA Astrophysics Data System (ADS)
Qu, Zhou; Xu, Haifeng; Sui, Xin; Yang, Kun
2015-10-01
With the development of science and technology, precision-strike weapons has been considered to be important for winning victory in military field. Laser guidance is a major method to execute precision-strike in modern warfare. At present, the problems of primary stage of Laser guidance has been solved with endeavors of countries. Several technical aspects of laser-beam riding guided system have been mature, such as atmosphere penetration of laser beam, clutter inhibition on ground, laser irradiator, encoding and decoding of laser beam. Further, laser beam quality, equal output power and atmospheric transmission properties are qualified for warfare situation. Riding guidance instrument is a crucial element of Laser-beam riding guided system, and is also a vital element of airborne, vehicle-mounted and individual weapon. The optical system mainly consist of sighting module and laser-beam guided module. Photoelectric detector is the most important sensing device of seeker, and also the key to acquire the coordinate information of target space. Currently, in consideration of the 1.06 u m of wavelength applied in all the semi-active laser guided weapons systems, lithium drifting silicon photodiode which is sensitive to 1.06 u m of wavelength is used in photoelectric detector. Compared to Solid and gas laser, diode laser has many merits such as small volume, simple construction, light weight, long life, low lost and easy modulation. This article introduced the composition and operating principle of Laser-beam riding guided system based on 980 nm diode laser, and made a analysis of key technology; for instance, laser irradiator, modulating disk of component, laser zooming system. Through the use of laser diode, Laser-beam riding guided system is likely to have smaller shape and very light.
Competency-Based Curriculum Guide for Laser Technology. September 1980-June 1981.
ERIC Educational Resources Information Center
Fioroni, John J.
This document contains materials developed by a project to provide a competency-based curriculum guide for laser technology at the community college level. An abstract of the final report is included. Next, the 17 job competencies determined as necessary to meet the job description of laser technician are listed. A career ladder and qualifications…
Compact 2100 nm laser diode module for next-generation DIRCM
NASA Astrophysics Data System (ADS)
Dvinelis, Edgaras; Greibus, Mindaugas; TrinkÅ«nas, Augustinas; NaujokaitÄ--, Greta; Vizbaras, Augustinas; Vizbaras, Dominykas; Vizbaras, Kristijonas
2017-10-01
Compact high-power 2100 nm laser diode module for next-generation directional infrared countermeasure (DIRCM) systems is presented. Next-generation DIRCM systems require compact, light-weight and robust laser modules which could provide intense IR light emission capable of disrupting the tracking sensor of heat-seeking missile. Currently used solid-state and fiber laser solutions for mid-IR band are bulky and heavy making them difficult to implement in smaller form-factor DIRCM systems. Recent development of GaSb laser diode technology greatly improved optical output powers and efficiencies of laser diodes working in 1900 - 2450 nm band [1] while also maintaining very attractive size, weight, power consumption and cost characteristics. 2100 nm laser diode module presented in this work performance is based on high-efficiency broad emitting area GaSb laser diode technology. Each laser diode emitter is able to provide 1 W of CW output optical power with working point efficiency up to 20% at temperature of 20 °C. For output beam collimation custom designed fast-axis collimator and slow-axis collimator lenses were used. These lenses were actively aligned and attached using UV epoxy curing. Total 2 emitters stacked vertically were used in 2100 nm laser diode module. Final optical output power of the module goes up to 2 W at temperature of 20 °C. Total dimensions of the laser diode module are 35 x 25 x 16 mm (L x W x H) with a weight of 28 grams. Finally output beam is bore-sighted to mechanical axes of the module housing allowing for easy integration into next-generation DIRCM systems.
Er:YAG laser for endodontics: efficiency and safety
NASA Astrophysics Data System (ADS)
Hibst, Raimund; Stock, Karl; Gall, Robert; Keller, Ulrich
1997-12-01
Recently it has been shown that bacterias can be sterilized by Er:YAG laser irradiation. By optical fiber transmission the bactericidal effect can also be used in endodontics. In order to explore potential laser parameters, we further investigated sterilization of caries and measured temperatures in models simulating endodontic treatment. It was found out that the bactericidal effect is cumulative, with single pulses being active. This offers to choose all laser parameters except pulse energy (radiant exposure) from technical, practical or safety considerations. For clinical studies the following parameter set is proposed for efficient and safe application (teeth with a root wall thickness > 1 mm, and prepared up to ISO 50): pulse energy: 50 mJ, repetition rate: 15 Hz, fiber withdrawal velocity: 2 mm/s. With these settings 4 passes must be performed to accumulate the total dose for sterilization.
Recent developments and near term directions for Navy laser weapons system (LaWS) testbed
NASA Astrophysics Data System (ADS)
Pawlak, Robert J.
2012-11-01
The Laser Weapons System (LaWS) testbed has been a demonstrator of many High Energy Laser (HEL)-related technologies for the Navy. LaWS employs a sharedaperture design with incoherent beam combining, and makes extensive use of Commercial Off-The-Shelf (COTS) technologies in the areas of inertial sensing, fiber lasers, sensors, and video trackers. Since the system has demonstrated the art of the possible with COTS elements, it is useful to examine where performance can be increased with the greatest possible effect, as well as which modifications are necessary to support better integration with ships' systems. A review of past test events, architectures, and further plans will be provided, while emphasizing the past and future evolution of the LaWS system. These evolutions will relate within the context of technical drivers that most affected system development.
Histological effects of He-Ne laser on the healing of experimental colon anastomoses in the rat
NASA Astrophysics Data System (ADS)
Asencio-Arana, Francisco; Torres-Gil, Vicente; Martinez-Soriano, Francisco; Perez-Sarrio, R.
1990-06-01
Despite technical advances, the incidence of anastomotic leaks in elective colorectal surgery remains around 14%, Recent studies suggest that the use of low energy lasers may enhance wound healing in different tissues in a selective, nondestructive manner. Based on these findings we have attempted to provide experimental background on the histological effects of He-Ne laser during the early stages of healing in 70 colonic anastornoses performed on rats, The irradiation of the anastomoses by two doses of 3.6 J/cm produces an increase in the populations of round cells and fibroblasts of the scar tissue, an increase in new vessel formation and a significant improvement in epithelialization. This suggests that the irradiation of colonic wounds with He-Ne lasers can result in an enhancement of healing.
Kulikov, Alexei N; Maltsev, Dmitrii S; Boiko, Ernest V
2016-01-01
Purpose . To compare three 360°-laser retinopexy (LRP) approaches (using navigated pattern laser system, single-spot slit-lamp (SL) laser delivery, and single-spot indirect ophthalmoscope (IO) laser delivery) in regard to procedure duration, procedural pain score, technical difficulties, and the ability to achieve surgical goals. Material and Methods . Eighty-six rhegmatogenous retinal detachment patients (86 eyes) were included in this prospective randomized study. The mean procedural time, procedural pain score (using 4-point Verbal Rating Scale), number of laser burns, and achievement of the surgical goals were compared between three groups (pattern LRP (Navilas® laser system), 36 patients; SL-LRP, 28 patients; and IO-LRP, 22 patients). Results . In the pattern LRP group, the amount of time needed for LRP and pain level were statistically significantly lower, whereas the number of applied laser burns was higher compared to those in the SL-LRP group and in the IO-LRP group. In the pattern LRP, SL-LRP, and IO-LRP groups, surgical goals were fully achieved in 28 (77.8%), 17 (60.7%), and 13 patients (59.1%), respectively ( p > 0.05). Conclusion . The navigated pattern approach allows improving the treatment time and pain in postoperative 360° LRP. Moreover, 360° pattern LRP is at least as effective in achieving the surgical goal as the conventional (slit-lamp or indirect ophthalmoscope) approaches with a single-spot laser.
Studying the Cost and Value of Library Services: Final Report. Technical Report APLAB/94-3/1,2,3,4.
ERIC Educational Resources Information Center
Kantor, Paul B.; And Others
This is the final technical report (in three parts) of a 15-month long project to study the costs and value of library functions at five major research libraries. Twenty-one services or service aspects were studied, and numerous measures of the importance or benefit of the service to the users were made. These measures were studied together to lay…
ERIC Educational Resources Information Center
Zull, Carolyn Gifford, Ed.; And Others
This third volume of the Comparative Systems Laboratory (CSL) Final Technical Report is a collection of relatively independent studies performed on CSL materials. Covered in this document are studies on: (1) properties of files, including a study of the growth rate of a dictionary of index terms as influenced by number of documents in the file and…
ERIC Educational Resources Information Center
Hammond, Cathy; Withington, Cairen; Sharp, Julia L.; Mobley, Catherine; Drew, Sam F.; Stringfield, Samuel C.; Stipanovic, Natalie; Swiger, Caroline M.; Daugherty, Lindsay; Griffith, Cathy
2014-01-01
This final report presents findings from data collection and analysis conducted during a five-year study by the National Dropout Prevention Center (NDPC) at Clemson University, in conjunction with colleagues from the National Research Center for Career and Technical Education (NRCCTE) at the University of Louisville. This project was one of three…
Ground-Based Radiometric Measurements of Slant Path Attenuation in the V/W Bands
2016-04-01
GROUND-BASED RADIOMETRIC MEASUREMENTS OF SLANT PATH ATTENUATION IN THE V/W BANDS APRIL 2016 FINAL TECHNICAL REPORT APPROVED FOR PUBLIC RELEASE...2. REPORT TYPE FINAL TECHNICAL REPORT 3. DATES COVERED (From - To) OCT 2012 – SEP 2015 4. TITLE AND SUBTITLE GROUND-BASED RADIOMETRIC MEASUREMENTS ...SUPPLEMENTARY NOTES 14. ABSTRACT Ground-based radiometric techniques were applied to measure the slant path attenuation cumulative distribution function to
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bender, W.
2013-01-01
Final technical progress report of SunShot Incubator Solaflect Energy. The project succeeded in demonstrating that the Solaflect Suspension Heliostat design is viable for large-scale CSP installations. Canting accuracy is acceptable and is continually improving as Solaflect improves its understanding of this design. Cost reduction initiatives were successful, and there are still many opportunities for further development and further cost reduction.
Basic research for the geodynamics program
NASA Technical Reports Server (NTRS)
Mueller, I. I.
1985-01-01
The current technical objectives for the geodynamics program consist of (1) optimal utilization of laser and Very Long Baseline Interferometry (VLBI) observations for reference frames for geodynamics; (2) utilization of range difference observations in geodynamics; and (3) estimation techniques in crustal deformation analysis.
Adaptability Through Modular Materials
ERIC Educational Resources Information Center
Hull, Daniel M.; And Others
1974-01-01
Several short articles describe programs utilizing laser/electro-optics technology curriculum materials developed by Technical Education Research Centers (TERC): at undergraduate and graduate levels in universities; in a city college; in continuing education; and in industry. Modules, independent units based on booklets or films, include…
Fog Bank Detector Field Tests : A Technical Summary
DOT National Transportation Integrated Search
1971-12-01
The report summarizes the results of field experiments performed at Pt. Bonita, California. The system under study, a laser LIDAR and a vertical-scanning infrared radiometer, have been discussed in detail in Report No. DOT-TSC-CG-71-3. Measurements o...
Laser beam riding guided system principle and design research
NASA Astrophysics Data System (ADS)
Qu, Zhou; Jin, Yi; Xu, Zhou; Xing, Hao
2016-01-01
With the development of science and technology, precision-strike weapons has been considered to be important for winning victory in military field. Laser guidance is a major method to execute precision-strike in modern warfare. At present, the problems of primary stage of Laser guidance has been solved with endeavors of countries. Several technical aspects of laser-beam riding guided system have been mature, such as atmosphere penetration of laser beam, clutter inhibition on ground, laser irradiator, encoding and decoding of laser beam. Further, laser beam quality, equal output power and atmospheric transmission properties are qualified for warfare situation. Riding guidance instrument is a crucial element of Laser-beam riding guided system, and is also a vital element of airborne, vehicle-mounted and individual weapon. The optical system mainly consist of sighting module and laser-beam guided module. Photoelectric detector is the most important sensing device of seeker, and also the key to acquire the coordinate information of target space. Currently, in consideration of the 1.06 u m of wavelength applied in all the semi-active laser guided weapons systems, lithium drifting silicon photodiode which is sensitive to 1.06 u m of wavelength is used in photoelectric detector. Compared to Solid and gas laser, diode laser has many merits such as small volume, simple construction, light weight, long life, low lost and easy modulation. This article introduced the composition and operating principle of Laser-beam riding guided system based on 980 nm diode laser, and made a analysis of key technology; for instance, laser irradiator, modulating disk of component, laser zooming system. Through the use of laser diode, Laser-beam riding guided system is likely to have smaller shape and very light.
Prototyping of Dental Structures Using Laser Milling
NASA Astrophysics Data System (ADS)
Andreev, A. O.; Kosenko, M. S.; Petrovskiy, V. N.; Mironov, V. D.
2016-02-01
The results of experimental studies of the effect of an ytterbium fiber laser radiation parameters on processing efficiency and quality of ZrO2 ceramics widely used in stomatology are presented. Laser operating conditions with optimum characteristics for obtaining high quality final surfaces and rapid material removal of dental structures are determined. The ability of forming thin-walled ceramic structures by laser milling technology (a minimum wall thickness of 50 μm) is demonstrated. The examples of three-dimensional dental structures created in computer 3D-models of human teeth using laser milling are shown.
Excimer laser ablation of the cornea
NASA Astrophysics Data System (ADS)
Pettit, George H.; Ediger, Marwood N.; Weiblinger, Richard P.
1995-03-01
Pulsed ultraviolet laser ablation is being extensively investigated clinically to reshape the optical surface of the eye and correct vision defects. Current knowledge of the laser/tissue interaction and the present state of the clinical evaluation are reviewed. In addition, the principal findings of internal Food and Drug Administration research are described in some detail, including a risk assessment of the laser-induced-fluorescence and measurement of the nonlinear optical properties of cornea during the intense UV irradiation. Finally, a survey is presented of the alternative laser technologies being explored for this ophthalmic application.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, J F
2007-01-31
This final report will cover work performed over the period of November 11, 2005 to September 30, 2006 on the contract to develop technologies using laser sources for radiation effects sciences. The report will discuss four topic areas; the laser source experiments on the Gekko Laser at Osaka, Japan, planning for the Charge State Freeze Out experiments to be performed in calendar year 2007, a review of previous xenon gasbags on the LANL Trident laser to provide planning support to the May-June 2007 HELEN experiments.
NASA Astrophysics Data System (ADS)
Jiang, Hongyan; Qiu, Hongbing; He, Ning; Liao, Xin
2018-06-01
For the optoacoustic communication from in-air platforms to submerged apparatus, a method based on speech recognition and variable laser-pulse repetition rates is proposed, which realizes character encoding and transmission for speech. Firstly, the theories and spectrum characteristics of the laser-generated underwater sound are analyzed; and moreover character conversion and encoding for speech as well as the pattern of codes for laser modulation is studied; lastly experiments to verify the system design are carried out. Results show that the optoacoustic system, where laser modulation is controlled by speech-to-character baseband codes, is beneficial to improve flexibility in receiving location for underwater targets as well as real-time performance in information transmission. In the overwater transmitter, a pulse laser is controlled to radiate by speech signals with several repetition rates randomly selected in the range of one to fifty Hz, and then in the underwater receiver laser pulse repetition rate and data can be acquired by the preamble and information codes of the corresponding laser-generated sound. When the energy of the laser pulse is appropriate, real-time transmission for speaker-independent speech can be realized in that way, which solves the problem of underwater bandwidth resource and provides a technical approach for the air-sea communication.
NASA Technical Reports Server (NTRS)
1995-01-01
The purpose of the Advanced Transportation System Studies (ATSS) Technical Area 2 (TA-2) Heavy Lift Launch Vehicle Development contract was to provide advanced launch vehicle concept definition and analysis to assist NASA in the identification of future launch vehicle requirements. Contracted analysis activities included vehicle sizing and performance analysis, subsystem concept definition, propulsion subsystem definition (foreign and domestic), ground operations and facilities analysis, and life cycle cost estimation. This document is Volume 2 of the final report for the contract. It provides documentation of selected technical results from various TA-2 analysis activities, including a detailed narrative description of the SSTO concept assessment results, a user's guide for the associated SSTO sizing tools, an SSTO turnaround assessment report, an executive summary of the ground operations assessments performed during the first year of the contract, a configuration-independent vehicle health management system requirements report, a copy of all major TA-2 contract presentations, a copy of the FLO launch vehicle final report, and references to Pratt & Whitney's TA-2 sponsored final reports regarding the identification of Russian main propulsion technologies.
Technical Evaluation Motor No. 7 (TEM-7)
NASA Technical Reports Server (NTRS)
Hughes, Phil
1991-01-01
The Technical Evaluation Motor No. 7 (TEM-7) test was a full-scale, full duration static test firing of a high performance motor-configuration solid rocket motor with nozzle vectoring. The final test report documents the procedures, performance, and results of the static test firing of TEM-7. All observations, discussions, conclusions, and recommendations included in the report are complete and final except for the TEM-7 fixed housing unbond investigation. A presentation and discussion of TEM-7 performance, anomalies, and test result concurrence with the objectives outlined in CTP-0107, Rev A, Space Shuttle Technical Evaluation Motor No. 7 (TEM-7) Static Fire Test Plan are included.
Building Stronger State Energy Partnerships with the U.S. Department of Energy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marks, Kate
2011-09-30
This final technical report details the results of total work efforts and progress made from October 2007 – September 2011 under the National Association of State Energy Officials (NASEO) cooperative agreement DE-FC26-07NT43264, Building Stronger State Energy Partnerships with the U.S. Department of Energy. Major topical project areas in this final report include work efforts in the following areas: Energy Assurance and Critical Infrastructure, State and Regional Technical Assistance, Regional Initiative, Regional Coordination and Technical Assistance, and International Activities in China. All required deliverables have been provided to the National Energy Technology Laboratory and DOE program officials.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Madhav Rao Gonvindaraju
1999-10-18
Die casting dies used in the metal casting industry fail due to thermal fatigue cracking accompanied by the presence of residual tensile stresses, corrosion, erosion and wear of die surfaces. This phase 1 SBIR Final Report summarize Karta Technologies research involving the development of an innovative laser coating technology for metal casting dies. The process involves depositing complex protective coatings of nanocrystalline powders of TiC followed by a laser shot peening. The results indicate a significant improvement in corrosion and erosion resistance in molten aluminum for H13 die casting die steels. The laser-coated samples also showed improved surface finish, amore » homogeneous and uniform coating mircrostructure. The technology developed in this research can have a significant impact on the casting industry by saving the material costs involved in replacing dies, reducing downtime and improving the quality.« less
2013-12-05
visible light on instruments such as microscope tips and micro- surgical tools. Hard carbon known as diamond-like carbon films produced by pulsed laser ...visible (610 nm) LED source and a supplemental infra-red 980-nm laser diode (for the studies of the upconversion fluorescence). The basic package...5/2013 Final Performance Report 15 Sep 2012- 14 Sep 2013 LASER DEPOSITION OF POLYMER NANOCOMPOSITE THIN FILMS AND HARD MATERIALS AND THEIR OPTICAL
Spatially Modulated Gain Waveguide Electro-Optic Laser
2013-08-09
1997, pp 1223-1226. 5. Y. Li, S. M. Goldwasser, P. Herczfeld, L.M. Narducci, "Dynamics of an electro-optically tunable microchip laser ", IEEE...TYPE Final 3. DATES COVERED (From 7/2/2010-5-10-2013 To) 4. TITLE AND SUBTITLE Spatially modulated gain waveguide electro-optic laser 5a...optical waveguides laser on LiNb03 substrate. The main goal of this work is to implement an active LiNb03 waveguide with the desired spatially modulated
Obsidianus lapis rugosity and hardness determination: fibre laser craftsmanship
NASA Astrophysics Data System (ADS)
Aguilar-Morales, A. I.; Velazquez-Gonzalez, J. S.; Marrujo-García, S.; Reyes-Sanchez, J. I.; Alvarez-Chávez, J. A.
2014-05-01
Obsidianus lapis is a volcanic rock that has been worked into tools for cutting or weaponry by Teotihuacan people for hundreds of years. Currently it is used in jewelry or for house decorative items such as elaborated sculptures. From the physico-chemical properties point of view, obsidianus lapis is considered a glass as its composition is 80% silicon dioxide. In México there are different kinds of obsidianus lapis according to its colour: rainbow, black, brown, red, silver, golden and snowflake. The traditional grinding process for working with obsidianus lapis includes fixed grinders and sandpaper for the polishing process, where the craftsman grinds the rock manually obtaining a variety of shapes. Laser processing of natural stones is a relatively new topic. We propose the use of an Yb3+-doped fibre laser for cutting and ablating obsidianus lapis into spherical, rectangular and oval shapes. By means of a theoretical analysis of roughness and hardness, which affect the different surfaces and final shapes, and considering the changes in material temperature during laser interaction, this work will focus on parameter determination such as: laser fluence, incidence angle, laser average power and peak pulse energy, from the proposed Q-switched fibre laser design. Full optical, hardness and rugosity, initial and final, characterization will be included in the presentation.
NASA Astrophysics Data System (ADS)
Xia, Wenze; Ma, Yayun; Han, Shaokun; Wang, Yulin; Liu, Fei; Zhai, Yu
2018-06-01
One of the most important goals of research on three-dimensional nonscanning laser imaging systems is the improvement of the illumination system. In this paper, a new three-dimensional nonscanning laser imaging system based on the illumination pattern of a point-light-source array is proposed. This array is obtained using a fiber array connected to a laser array with each unit laser having independent control circuits. This system uses a point-to-point imaging process, which is realized using the exact corresponding optical relationship between the point-light-source array and a linear-mode avalanche photodiode array detector. The complete working process of this system is explained in detail, and the mathematical model of this system containing four equations is established. A simulated contrast experiment and two real contrast experiments which use the simplified setup without a laser array are performed. The final results demonstrate that unlike a conventional three-dimensional nonscanning laser imaging system, the proposed system meets all the requirements of an eligible illumination system. Finally, the imaging performance of this system is analyzed under defocusing situations, and analytical results show that the system has good defocusing robustness and can be easily adjusted in real applications.
NASA Astrophysics Data System (ADS)
Li, T.; Lou, Q.; Dong, J.; Wei, Y.; Liu, J.
Surface ablation of cobalt-cemented tungsten carbide hard metal has been carried out in this work using a 308 nm, 20 ns XeCl excimer laser. Surface microphotography and XRD, as well as an electron probe have been used to investigate the transformation of phase and microstructure as a function of the pulse-number of laser shots at a laser fluence of 2.5 J/cm2. The experimental results show that the microstructure of cemented tungsten carbide is transformed from the original polygonal grains of size 3 μm to interlaced large, long grains with an increase in the number of laser shots up to 300, and finally to gross grains of size 10 μm with clear grain boundaries after 700 shots of laser irradiation. The crystalline structure of the irradiated area is partly transformed from the original WC to βWC1-x, then to αW2C and CW3, and finally to W crystal. It is suggested that the undulating `hill-valley' morphology may be the result of selective removal of cobalt binder from the surface layer of the hard metal. The formation of non-stoichiometric tungsten carbide may result from the escape of elemental carbon due to accumulated heating of the surface by pulsed laser irradiation.
Enabling lunar and space missions by laser power transmission
NASA Technical Reports Server (NTRS)
Deyoung, R. J.; Nealy, J. E.; Humes, D. H.; Meador, W. E.
1992-01-01
Applications are proposed for laser power transmission on the Moon. A solar-pumped laser in lunar orbit would beam power to the lunar surface for conversion into either electricity or propulsion needs. For example, lunar rovers could be much more flexible and lighter than rovers using other primary power sources. Also, laser power could be absorbed by lunar soil to create a hard glassy surface for dust-free roadways and launch pads. Laser power could also be used to power small lunar rockets or orbital transfer vehicles, and finally, photovoltaic laser converters could power remote excavation vehicles and human habitats. Laser power transmission is shown to be a highly flexible, enabling primary power source for lunar missions.
Studies of new media radiation induced laser. Final Report, 1 February 1979-30 April 1984
DOE Office of Scientific and Technical Information (OSTI.GOV)
Han, K.S.; Shiu, Y.J.; Raju, S.R.
Various lasants were investigated especially, 2-iodohepafluoropropane (i-C3F7I) for the direct solar pumped lasers. Optical pumping of iodine laser was achieved using a small flashlamp. Using i-C3F7I as a laser gain medium, threshold inversion density, small signal gain, and laser performance at the elevated temperature were measured. The experimental results and analysis are presented. The iodine laser kinetics of the C3F7I and IBr system were numerically simulated. The concept of a direct solar-pumped laser amplifier using (i-C3F7I) as the laser material was evaluated and several kinetic coefficients for i-C3F7I laser system were reexamined. The results are discussed.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-06-07
...] Guidance for Industry and Food and Drug Administration Staff: Technical Considerations for Pen, Jet, and... availability of a final guidance document entitled ``Technical Considerations for Pen, Jet, and Related... developing information to support a marketing application for a pen, jet, or related injector device intended...
Florida Study of Career and Technical Education. Final Report
ERIC Educational Resources Information Center
Jacobson, Louis; Mokher, Christine
2014-01-01
A key goal of the "Carl D. Perkins Career and Technical Education Act of 2006" ("Perkins IV") is to ensure career and technical education (CTE) programs are widely available for preparing high school and college students for "high skill, high wage, or high demand occupations in current or emerging professions"…
Active space debris removal by using laser propulsion
NASA Astrophysics Data System (ADS)
Rezunkov, Yu. A.
2013-03-01
At present, a few projects on the space debris removal by using highpower lasers are developed. One of the established projects is the ORION proposed by Claude Phipps from Photonics Associates Company and supported by NASA (USA) [1]. But the technical feasibility of the concept is limited by sizes of the debris objects (from 1 to 10 cm) because of a small thrust impulse generated at the laser ablation of the debris materials. At the same time, the removal of rocket upper stages and satellites, which have reached the end of their lives, has been carried out only in a very small number of cases and most of them remain on the Low Earth Orbits (LEO). To reduce the amount of these large-size objects, designing of space systems allowing deorbiting upper rocket stages and removing large-size satellite remnants from economically and scientifically useful orbits to disposal ones is considered. The suggested system is based on high-power laser propulsion. Laser-Orbital Transfer Vehicle (LOTV) with the developed aerospace laser propulsion engine is considered as applied to the problem of mitigation of man-made large-size space debris in LEO.
NASA Astrophysics Data System (ADS)
Cannon, B. D.
1993-10-01
Isotopically-selective excitation of uranium atoms by diode lasers can be the basis for a portable instrument to perform uranium isotopic assays in the field. Such an instrument would improve the ability of on-site inspections to detect and deter nuclear proliferation. Published and unpublished spectroscopic data on atomic uranium were examined to identify candidate transitions for isotopically-selective laser excitation with diode lasers. Eleven candidate transitions were identified and evaluated for their potential usefulness for a portable uranium assay instrument. Eight of these transitions are suitable for laser induced fluorescence using different excitation and detection wavelengths, which will improve sensitivity and elemental selectivity. Data sheets on the 25 uranium transitions in the wavelength range 629 nm to 1,000 nm that originate in the ground or first excited states of neutral atomic uranium are included. Each data sheet provides the wavelength, upper and lower energy levels, angular momentum quantum numbers, U-235 isotope shift (relative to U-238, and high-resolution spectra of weapons-grade uranium (93% U-235 and 7% U-238).
Transcanalicular laser-assisted dacryocystorhinostomy.
Rosen, N; Barak, A; Rosner, M
1997-09-01
Current techniques of laser-assisted dacryocystorhinostomy are mostly endonasal. In this report, the authors describe their technique of laser-assisted dacryocystorhinostomy performed through the canaliculi and the surgical results they achieved. Fourteen patients with nasolacrimal duct obstruction underwent transcanalicular laser-assisted dacryocystorhinostomy. The bony ostium was perforated using a fiber optic-transmitting, giant-pulse Nd:YAG laser, with an energy of 0.5 to 4 J per pulse. The total energy used to create an ostium was 18 to 34 J. A silicone tube was inserted through the canaliculi and the ostium into the nasal cavity and kept in place for 5 to 7 months. Patients were observed for 18 to 22 months. Nine of the 14 patients (64%) reported the disappearance of epiphora following surgery. In 3 patients, no relief of epiphora was obtained. In 1 patient the operation was not completed because of severe nasal bleeding. In another, tearing began 12 months after surgery (6 months after tube removal). Transcanalicular laser-assisted dacryocystorhinostomy is a potentially useful method for performing dacryocystorhinostomy. Technical modifications and improvements are needed to increase the success rate.
NASA Astrophysics Data System (ADS)
Ghazai, A. J.; Thahab, S. M.; Hassan, H. Abu; Hassan, Z.
2010-07-01
The development of efficient MQWs active regions of quaternary InAlGaN in the ultraviolet (UV) region is an engaging challenge by itself. Demonstrating lasers at such low wavelength will require resolving a number of materials, growth and device design issues. However, the quaternary AlInGaN represents a more versatile material since the bandgap and lattice constant can be independently varied. We report a quaternary AlInGaN double-quantum wells (DQWs) UV laser diode (LDs) study by using the simulation program of Integrated System Engineering-Technical Computer Aided Design (ISE TCAD). Advanced physical models of semiconductor properties were used. In this paper, the enhancement in the performance of AlInGaN laser diode can be achieved by optimizing the laser structure geometry design. The AlInGaN laser diodes operating parameters such as internal quantum efficiency ηi, internal loss αi and transparency threshold current density show effective improvements that contribute to a better performance.
D Survey in Complex Archaeological Environments: AN Approach by Terrestrial Laser Scanning
NASA Astrophysics Data System (ADS)
Ebolese, D.; Dardanelli, G.; Lo Brutto, M.; Sciortino, R.
2018-05-01
The survey of archaeological sites by appropriate geomatics technologies is an important research topic. In particular, the 3D survey by terrestrial laser scanning has become a common practice for 3D archaeological data collection. Even if terrestrial laser scanning survey is quite well established, due to the complexity of the most archaeological contexts, many issues can arise and make the survey more difficult. The aim of this work is to describe the methodology chosen for a terrestrial laser scanning survey in a complex archaeological environment according to the issues related to the particular structure of the site. The developed approach was used for the terrestrial laser scanning survey and documentation of a part of the archaeological site of Elaiussa Sebaste in Turkey. The proposed technical solutions have allowed providing an accurate and detailed 3D dataset of the study area. In addition, further products useful for archaeological analysis were also obtained from the 3D dataset of the study area.
New laser design for NIR lidar applications
NASA Astrophysics Data System (ADS)
Vogelmann, H.; Trickl, T.; Perfahl, M.; Biggel, S.
2018-04-01
Recently, we quantified the very high spatio-temporal short term variability of tropospheric water vapor in a three dimensional study [1]. From a technical point of view this also depicted the general requirement of short integration times for recording water-vapor profiles with lidar. For this purpose, the only suitable technique is the differential absorption lidar (DIAL) working in the near-infrared (NIR) spectral region. The laser emission of most water vapor DIAL systems is generated by Ti:sapphire or alexandrite lasers. The water vapor absorption band at 817 nm is predominated for the use of Ti:sapphire. We present a new concept of transversely pumping in a Ti:Sapphire amplification stage as well as a compact laser design for the generation of single mode NIR pulses with two different DIAL wavelengths inside a single resonator. This laser concept allows for high output power due to repetitions rates up to 100Hz or even more. It is, because of its compactness, also suitable for mobile applications.
Damage resistant optics for a mega-joule solid-state laser
NASA Astrophysics Data System (ADS)
Campbell, J. H.; Rainer, F.; Kozlowski, M. R.; Wolfe, C. R.; Thomas, I.; Milanovich, F.
1990-12-01
Research on Inertial Confinement Fusion (ICF) has progressed rapidly in the past several years. As a consequence, LLNL is developing plans to upgrade the current 120 kJ solid state (Nd3+ phosphate glass) Nova laser to a 1.5 to 2 megajoule system with the goal of achieving fusion ignition. The design of the planned Nova Upgrade is briefly discussed. Because of recent improvements in the damage resistance of optical materials it is now technically and economically feasible to build a megajoule-class solid state laser. Specifically, the damage threshold of Nd(+3)-doped phosphate laser glass, multilayer dielectric coatings, and non-linear optical crystals (e.g., KDP) have been dramatically improved. These materials now meet the fluence requirements for a 1.5 to 2 MJ Nd(+3)-glass laser operating at 1054 and 351 nm and at a pulse length of 3 ns. The recent improvements in damage thresholds are reviewed; threshold data at both 1064 and 355 nm and the measured pulse length scaling are presented.
Damage resistant optics for a megajoule solid state laser
NASA Astrophysics Data System (ADS)
Campbell, Jack H.; Rainer, Frank; Kozlowski, Mark R.; Wolfe, C. Robert; Thomas, Ian M.; Milanovich, Fred P.
1991-06-01
Research on Inertial Confinement Fusion (ICF) has progressed rapidly in the past several years. As a consequence LLNL is developing plans to upgrade the current 120 kJ solid state (Nd3-phosphate glass) Nova laser to a 1 . 5 to 2 megajoule system with the goal of achieving fusion ignition. The design of the planned Nova Upgrade is briefly discussed. Because of recent improvements in the damage resistance of optical materials it is now technically and economically feasible to build a megajoule-class solid state laser. Specifically the damage threshold of Nd3- doped phosphate laser glass muliilayer dielectric coatings and non-linear optical crystals (e. g. KDP) have been dramatically improved. These materials now meet the fluence requirements for a 1. 5-2 MJ Nd3-glass laser operating at 1054 and 351 nm and at a pulse length of 3 ns. The recent improvements in damage thresholds are reviewed threshold data at both 1064 and 355 nm and the measured pulse length scaling are presented. 1.
The Status of Turkish Accelerator Center Test Facility
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yavas, Oe.
2007-04-23
Recently, conceptual design of Turkic Accelerator Center (TAC) proposal was completed. Main goal of this proposal is a charm factory that consists of a linac-ring type electron-positron collider. In addition, synchrotron radiation from the positron ring and free electron laser from the electron linac are proposed. The project related with this proposal has been accepted by Turkish government. It is planned that the Technical Design Report of TAC will have been written in next three years. In this period, an infrared oscillator free electron laser (IR FEL) will be constructed as a test facility for TAC. 20 and 50 MeVmore » electron energies will be used to obtain infra red free electron laser. The main parameters of the electron linac, the optical cavities and the free electron laser were determined. The possible use of obtained laser beam in basic and applied research areas such as biotechnology, nanotechnology, semiconductors and photo chemistry were stated.« less
Non-critical phase-matching fourth harmonic generation of a 1053-nm laser in an ADP crystal
Ji, Shaohua; Wang, Fang; Zhu, Lili; Xu, Xinguang; Wang, Zhengping; Sun, Xun
2013-01-01
In current inertial confinement fusion (ICF) facilities, KDP and DKDP crystals are the second harmonic generation (SHG) and third harmonic generation (THG) materials for the Nd:glass laser (1053 nm). Based on the trend for the development of short wavelengths for ICF driving lasers, technical solutions for fourth harmonic generation (FHG) will undoubtedly attract more and more attention. In this paper, the rapid growth of an ADP crystal and non-critical phase-matching (NCPM) FHG of a 1053-nm laser using an ADP crystal are reported. The NCPM temperature is 33.7°C. The conversion efficiency from 526 to 263 nm is 70%, and the angular acceptance range is 55.4 mrad; these results are superior to those for the DKDP crystals. This research has shown that ADP crystals will be a competitive candidate in future ICF facilities when the utilisation of high-energy, high-efficiency UV lasers at wavelengths shorter than the present 351 nm is of interest. PMID:23549389
High-energy laser weapons since the early 1960s
NASA Astrophysics Data System (ADS)
Cook, Joung
2013-02-01
Both the U.S. and Russia/USSR have made great strides toward developing high-energy laser weapons for their future national defense systems since the early 1960s. Many billions of dollars and rubles were invested in the effort. Many hundreds of gifted scientists and engineers devoted their careers to working on the problems. They achieved major technological advances and made impressive and successful demonstrations. After more than half a century, however, neither side has yet adapted the first laser weapon for a military use. Why? This paper discusses the history of key technological advancements and successes, as well as some of the difficulties encountered. It also discusses fundamental technological advantages and limitations of high-energy laser weapons, and also the unique social, cultural, and political environments that have contributed to the history. The high-energy laser technical community is in the process of finding ways to adapt to the new warfare environment by taking advantage of the lessons learned in the past while incorporating the new technologies and ideas evolved in recent years.
Non-critical phase-matching fourth harmonic generation of a 1053-nm laser in an ADP crystal.
Ji, Shaohua; Wang, Fang; Zhu, Lili; Xu, Xinguang; Wang, Zhengping; Sun, Xun
2013-01-01
In current inertial confinement fusion (ICF) facilities, KDP and DKDP crystals are the second harmonic generation (SHG) and third harmonic generation (THG) materials for the Nd:glass laser (1053 nm). Based on the trend for the development of short wavelengths for ICF driving lasers, technical solutions for fourth harmonic generation (FHG) will undoubtedly attract more and more attention. In this paper, the rapid growth of an ADP crystal and non-critical phase-matching (NCPM) FHG of a 1053-nm laser using an ADP crystal are reported. The NCPM temperature is 33.7°C. The conversion efficiency from 526 to 263 nm is 70%, and the angular acceptance range is 55.4 mrad; these results are superior to those for the DKDP crystals. This research has shown that ADP crystals will be a competitive candidate in future ICF facilities when the utilisation of high-energy, high-efficiency UV lasers at wavelengths shorter than the present 351 nm is of interest.
Soldering mask laser removal from printed circuit boards aiming copper recycling.
Raele, Marcus Paulo; De Pretto, Lucas Ramos; Zezell, Denise Maria
2017-10-01
Management of waste of electric and electronic equipment (WEEE) is a key issue for modern societies; furthermore, it contains valuable materials that can be recycled, especially in printed circuit boards (PCB), which have approximately one-third of their weight in copper. In this study we demonstrated the use of laser to strip the covering soldering mask on PCB's, thus exposing the copper underneath so that extraction techniques may take place. Using a Q-Switched Nd:YAG laser operating at 1064nm and 532nm we tested the procedure under different energy conditions. The laser stripping of the soldering mask was achieved with satisfactory results by irradiation with 225mJ at 1064nm. However, when using similar parameters at 532nm the process of the coating ejection was not promoted properly, leading to a faulty detachment. Infrared laser PCB stripping presents itself to be technically viable and environmental friendly, since it uses no chemicals inputs, offering one more option to WEEE treatment and recycling. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Gales, S.; ELI-NP Team
2015-10-01
The development of high power lasers and the combination of such novel devices with accelerator technology has enlarged the science reach of many research fields, in particular High Energy, Nuclear and Astrophysics as well as societal applications in Material Science, Nuclear Energy and Medicine. The European Strategic Forum for Research Infrastructures (ESFRI) has selected a proposal based on these new premises called "ELI" for Extreme Light Infrastructure. ELI will be built as a network of three complementary pillars at the frontier of laser technologies. The ELI-NP pillar (NP for Nuclear Physics) is under construction near Bucharest (Romania) and will develop a scientific program using two 10 PW class lasers and a Back Compton Scattering High Brilliance and Intense Low Energy Gamma Beam, a marriage of Laser and Accelerator technology at the frontier of knowledge. In the present paper, the technical and scientific status of the project as well as the applications of the gamma source will be discussed.
Ramazani, Mohsen; Asnaashari, Mohammad; Ahmadi, Roghayyeh; Zarenejad, Nafiseh; Rafie, Alireza; Yazadani Charati, Jamshid
2018-01-01
This in vitro study aimed at comparing the effect of agitating the final irrigant solutions of root canal by ultrasonic or using 808 nm Diode laser on the apical seal of canal. A total of 90 extracted human maxillary central incisors were prepared up to size #45 and were randomly assigned to 4 experimental groups ( n =20) and two control groups ( n =5) respectively, as follows: I ): 3 mL of 5.25% NaOCl was agitated as final irrigant solution with ultrasonic for 30 sec. The ultrasonic tip was 1 mm shorter than the working length, II ): 3 mL of 5.25% NaOCl was agitated as final irrigant with 808 nm Diode laser for 30 sec. Fiber tip, placed in 1 mm shorter from working length was spirally moved coronally, III ): 3 mL of 17% EDTA was agitated as final irrigant with 808 nm Diode laser for 30 sec and was applied similar to group II, IV ): 3 mL of 17% EDTA was stimulated as final irrigant with ultrasonic for 30 sec and was applied similar to I. Apical seal was assessed by Dual Chamber technique using Bovine Serum Albumin protein. Kruskal-Wallis and Mann Whitney tests were used with significance level lower than 0.05% for statistical analysis. The average leakage in the negative control, positive control, and groups I, II, III, IV were: 0.00, 13.5±5.1, 1.72±2.9, 5.12±5.6, 3.36±3.7, 2.4±4.2, respectively. Statistical analysis showed significant difference between groups ( P <0.05). There was a significant difference between groups 1 and 2 in terms of protein leakage . Agitating 5.25% sodium hypochlorite solution as the final irrigant with ultrasonic is more effective in apical leakage reduction compared to other groups.
NASA Technical Reports Server (NTRS)
Frese, Erich A.; Chiragh, Furqan L.; Switzer, Robert; Vasilyev, Aleksey A.; Thomes, Joe; Coyle, D. Barry; Stysley, Paul R.
2018-01-01
Flight quality solid-state lasers require a unique and extensive set of testing and qualification processes, both at the system and component levels to insure the laser's promised performance. As important as the overall laser transmitter design is, the quality and performance of individual subassemblies, optics, and electro-optics dictate the final laser unit's quality. The Global Ecosystem Dynamics Investigation (GEDI) laser transmitters employ all the usual components typical for a diode-pumped, solid-state laser, yet must each go through their own individual process of specification, modeling, performance demonstration, inspection, and destructive testing. These qualification processes and results for the laser crystals, laser diode arrays, electro-optics, and optics, will be reviewed as well as the relevant critical issues encountered, prior to their installation in the GEDI flight laser units.
McKenzie, A L
1984-01-01
As the sales of surgical lasers continue to grow, the problem of laser safety in hospitals becomes increasingly more urgent. This article considers both the principles and the practice of laser safety, and indicates how safety codes should be organized within a hospital. Eye safety is of paramount importance, and the effects of different wavelengths of laser radiation on the eye are described, both for intrabeam and extended-source exposure. An account is given of the concept of Maximum Permissible Exposure (MPE) and how it depends upon wavelength and exposure duration. The standard laser classification is developed in relation to MPE. The use of laser protective eyewear is discussed for the surgeon, other theatre staff and the patient. Finally, the role of the Laser Protection Supervisor and of the Laser Protection Adviser are explained in the context of establishing a local laser safety code.
Optofluidic lasers and their applications in bioanalysis (Conference Presentation)
NASA Astrophysics Data System (ADS)
Fan, Xudong
2016-03-01
The optofluidic laser is an emerging technology that integrates microfluidics, miniaturized laser cavity, and laser gain medium in liquid. It is unique due to its biocompatibility, thus can be used for unconventional bioanalysis, in which biointeraction or process takes place within the optical cavity mode volume. Rather than using fluorescence, the optofluidic laser based detection employs laser emission, i.e., stimulated emission, as the sensing signal, which takes advantage of optical amplification provided by the laser cavity to achieve much higher sensitivity. In this presentation, I will first introduce the concept of optofluidic laser based bioanalysis. Then I will discuss each of the three components (cavity, gain medium, and fluidics) of the optofluidic laser and describe how to use the optofluidic laser in bioanalysis at the molecular, cellular, and tissue level. Finally, I will discuss future research and application directions.
Matrix Treatment of Ray Optics.
ERIC Educational Resources Information Center
Quon, W. Steve
1996-01-01
Describes a method to combine two learning experiences--optical physics and matrix mathematics--in a straightforward laboratory experiment that allows engineering/physics students to integrate a variety of learning insights and technical skills, including using lasers, studying refraction through thin lenses, applying concepts of matrix…
Electronic Document Supply Systems.
ERIC Educational Resources Information Center
Cawkell, A. E.
1991-01-01
Describes electronic document delivery systems used by libraries and document image processing systems used for business purposes. Topics discussed include technical specifications; analogue read-only laser videodiscs; compact discs and CD-ROM; WORM; facsimile; ADONIS (Article Delivery over Network Information System); DOCDEL; and systems at the…
Assessing LiDAR elevation data for KDOT applications : [technical summary].
DOT National Transportation Integrated Search
2013-02-01
LiDAR-based elevation surveys : are a cost-effective means for : mapping topography over large : areas. LiDAR surveys use an : airplane-mounted or ground-based : laser radar unit to scan terrain. : Post-processing techniques are : applied to remove v...
Friction management on Kansas Department of Transportation highways : technical summary.
DOT National Transportation Integrated Search
2017-04-01
The objectives of this study are to evaluate the performance of a local aggregate in HFST and to evaluate : the 3-dimensional laser profiler for measuring pavement texture. Slab specimens of hot-mix asphalt : (HMA) were compacted in the laboratory an...
Experimental and numerical investigation on laser-assisted bending of pre-loaded metal plate
NASA Astrophysics Data System (ADS)
Nowak, Zdzisław; Nowak, Marcin; Widłaszewski, Jacek; Kurp, Piotr
2018-01-01
The laser forming technique has an important disadvantage, which is the limitation of plastic deformation generated by a single laser beam pass. To increase the plastic deformation it is possible to apply external forces in the laser forming process. In this paper, we investigate the influence of external pre-loads on the laser bending of steel plate. The pre-loads investigated generate bending towards the laser beam. The thermal, elastic-plastic analysis is performed using the commercial nonlinear finite element analysis package ABAQUS. The focus of the paper is to identify how this pattern of the pre-load influence the final bend angle of the plate.
Laser diode initiated detonators for space applications
NASA Technical Reports Server (NTRS)
Ewick, David W.; Graham, J. A.; Hawley, J. D.
1993-01-01
Ensign Bickford Aerospace Company (EBAC) has over ten years of experience in the design and development of laser ordnance systems. Recent efforts have focused on the development of laser diode ordnance systems for space applications. Because the laser initiated detonators contain only insensitive secondary explosives, a high degree of system safety is achieved. Typical performance characteristics of a laser diode initiated detonator are described in this paper, including all-fire level, function time, and output. A finite difference model used at EBAC to predict detonator performance, is described and calculated results are compared to experimental data. Finally, the use of statistically designed experiments to evaluate performance of laser initiated detonators is discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Solares, Santiago D.
The final project report covering the period 7/1/14-6/30/17 provides an overview of the technical accomplishments in the areas of (i) fundamental viscoelasticity, (ii) multifrequency atomic force microscopy, and (iii) characterization of energy-relevant materials with atomic force microscopy. A list of publications supported by the project is also provided.
Application of Knowledge-Based Techniques to Tracking Function
2006-09-01
38394041 42434445 46474849 505152 53545556 57585960 616263 646566 676869 707172 737475 7677 7879 8081 8283 8485 8687 8889 9091 9293 9495 969798 99100...Knowledge-based applications to adaptive space-time processing. Volume I: Summary”, AFRL-SN-TR-2001-146 Vol. I (of Vol. VI ), Final Technical Report, July...2001-146 Vol. IV (of Vol. VI ), Final Technical Report, July 2001. [53] C. Morgan, L. Moyer, “Knowledge-based applications to adaptive space-time
ERIC Educational Resources Information Center
Powers, Thomas F., Ed.; Swinton, John R., Ed.
This third and final volume of a study on the future of the food service industry contains the technical papers on which the information in the previous two volumes was based. The papers were written by various members of the Pennsylvania State University departments of economics, food science, nutrition, social psychology, and engineering and by…
Final Technical Report for contract number DE-FG02-05ER15670
DOE Office of Scientific and Technical Information (OSTI.GOV)
Glazebrook, Jane
This is the final technical report for contract number DE-FG02-05ER15670. The project is now complete, and results of the project have been published. Two papers were published based on work done in the last three-year funding period. The DOIs of these papers are included below. The abstracts of the papers, providing summaries of the work, are included in the body of the report.
Modeling of high efficiency solar cells under laser pulse for power beaming applications
NASA Technical Reports Server (NTRS)
Jain, Raj K.; Landis, Geoffrey A.
1994-01-01
Solar cells have been used to convert sunlight to electrical energy for many years and also offer great potential for non-solar energy conversion applications. Their greatly improved performance under monochromatic light compared to sunlight, makes them suitable as photovoltaic (PV) receivers in laser power beaming applications. Laser beamed power to a PV array receiver could provide power to satellites, an orbital transfer vehicle, or a lunar base. Gallium arsenide (GaAs) and indium phosphide (InP) solar cells have calculated efficiencies of more than 50 percent under continuous illumination at the optimum wavelength. Currently high power free-electron lasers are being developed which operate in pulsed conditions. Understanding cell behavior under a laser pulse is important in the selection of the solar cell material and the laser. An experiment by NAsA lewis and JPL at the AVLIS laser facility in Livermore, CA presented experimental data on cell performance under pulsed laser illumination. Reference 5 contains an overview of technical issues concerning the use of solar cells for laser power conversion, written before the experiments were performed. As the experimental results showed, the actual effects of pulsed operation are more complicated. Reference 6 discusses simulations of the output of GaAs concentrator solar cells under pulsed laser illumination. The present paper continues this work, and compares the output of Si and GaAs solar cells.
2015-07-16
SECURITY CLASSIFICATION OF: The InAs quantum dot (QD) grown on GaAs substrates represents a highly performance active region in the 1 - 1.3 µm...2015 Approved for Public Release; Distribution Unlimited Final Report: Mode-locking of an InAs Quantum Dot Based Vertical External Cavity Surface...ABSTRACT Final Report: Mode-locking of an InAs Quantum Dot Based Vertical External Cavity Surface Emitting Laser Using Atomic Layer Graphene Report
Astrobee Periodic Technical Review (PTR) Delta 3
NASA Technical Reports Server (NTRS)
Provencher, Christopher; Smith, Marion F.; Smith, Ernest Everett; Bualat, Maria Gabriele; Barlow, Jonathan Spencer
2017-01-01
Astrobee is a free flying robot for the inside of the International Space Station (ISS). The Periodic Technical Review (PTR) delta 3 is the final design review of the system presented to stakeholders.
Polar source analysis : technical memorandum
DOT National Transportation Integrated Search
2017-09-29
The following technical memorandum describes the development, testing and analysis of various polar source data sets. The memorandum also includes recommendation for potential inclusion in future releases of AEDT. This memorandum is the final deliver...
2005 v4.2 Technical Support Document
Technical Support Document for the Final Transport Rule describes how updated 2005 NEI, version 2 emissions and were processed for air quality modeling in support of the Cross-state Air Pollution Rule (CSAPR).
Direct Final Rule for Technical Amendments for Marine Spark-Ignition Engines and Vessels
Rule published September 16, 2010 to make technical amendments to the design standard for portable marine fuel tanks. This rule incorporates safe recommended practices, developed through industry consensus.
Development of a red diode laser system for photodynamic therapy
NASA Astrophysics Data System (ADS)
Halkiotis, Konstantinos N.; Yova, Dido M.; Uzunoglou, Nikolaos K.; Papastergiou, Georgios; Matakias, Sotiris; Koukouvinos, Ilias
1998-07-01
The effectiveness of photodynamic treatment modality has been proven experimentally for a large variety of tumors, during the last years. This therapy utilizes the combined action of light and photosensitizing drug. Until now, a disadvantage of PDT has be the low tissue penetration of light, at the wavelengths of most commonly available lasers, for clinical studies. The red wavelength offers the advantage of increased penetration depth in tissue, in addition several new wavelength offers the advantage of increased penetration depth in tissue, in addition several new photosensitizers present absorption band at the region 630nm to 690nm. The development of high power red diode laser system for photodynamic therapy, has provided a cost effective alternative to existing lasers for use in PDT. This paper will describe the system design, development and performance of a diode laser system, connected with a fiber optic facility, to be used for PDT. The system was based on a high power semiconductor diode laser emitting at 655nm. The laser output power was approximately 60mW at the output of a 62.5/125/900 micron fiber optic probe. FUll technical details and optical performance characteristics of the system will be discussed in this paper.
Widely tunable laser frequency offset lock with 30 GHz range and 5 THz offset.
Biesheuvel, J; Noom, D W E; Salumbides, E J; Sheridan, K T; Ubachs, W; Koelemeij, J C J
2013-06-17
We demonstrate a simple and versatile method to greatly extend the tuning range of optical frequency shifting devices, such as acousto-optic modulators (AOMs). We use this method to stabilize the frequency of a tunable narrow-band continuous-wave (CW) laser to a transmission maximum of an external Fabry-Perot interferometer (FPI) with a tunable frequency offset. This is achieved through a servo loop which contains an in-loop AOM for simple radiofrequency (RF) tuning of the optical frequency over the full 30 GHz mode-hop-free tuning range of the CW laser. By stabilizing the length of the FPI to a stabilized helium-neon (HeNe) laser (at 5 THz offset from the tunable laser) we simultaneously transfer the ~ 1 MHz absolute frequency stability of the HeNe laser to the entire 30 GHz range of the tunable laser. Thus, our method allows simple, wide-range, fast and reproducible optical frequency tuning and absolute optical frequency measurements through RF electronics, which is here demonstrated by repeatedly recording a 27-GHz-wide molecular iodine spectrum at scan rates up to 500 MHz/s. General technical aspects that determine the performance of the method are discussed in detail.
Design of diode-pumped solid-state laser applied in laser fuses
NASA Astrophysics Data System (ADS)
Deng, FangLin; Zhang, YiFei
2005-04-01
The function of laser fuzes which are parts of certain weapon systems is to control the blasting height of warheads. Commonly the battle environment these weapon systems are confronted with is very complicated and the tactical demand for them is very rigor, so laser fuzes equipped for them must fulfill some special technical requirements, such as high repetition rate, long ranging scope, etc. Lasers are one of key components which constitute fuze systems. Whether designed lasers are advanced and reasonable will determine whether laser fuzes can be applied in these weapon systems or not. So we adopt the novel technology of diode-pumped solid-state laser (DPSSL) to design lasers applied in fuzes. Nd:YVO4 crystal is accepted as gain material, which has wide absorption band and large absorption efficient for 808nm pumping laser. As warhead's temperature is usually very high, wider absorption band is beneficial to reduce the influence of temperature fluctuation. Passive Q-switching with Cr4+:YAG is used to reduce the power consumption farthest. Design the end-pumped microchip sandwich-architecture to decrease lasers' size and increase the reliability, further it's advantageous to produce short pulses and increase peak power of lasers. The designed DPSSL features small size and weight, high repetition rate and peak power, robustness, etc. The repetition rate is expected to reach 1 kHz; peak power will exceed 300 kW; pulse width is only 5 ns; and divergence angle of laser beams is less than 5 mrad. So DPSSL is suitable for laser fuzes as an emitter.
Laser Atmospheric Wind Sounder (LAWS) phase 1. Volume 2
NASA Technical Reports Server (NTRS)
1990-01-01
This report summarizes and documents the results of the 12-month phase 1 work effort. The objective of phase 1 was to establish the conceptional definition of the laser atmospheric wind sounder (LAWS) sensor system, including accommodations analyses to ensure compatibility with the Space Station Freedom (SSF) and the Earth Observing System (EOS) Polar Orbiting Platform (POP). Various concepts were investigated with trade studies performed to select the configuration to be carried forward to the phase 2 Preliminary Design Definition. A summary of the LAWS system and subsystem trade studies that were performed leading to the baseline design configuration is presented in the appendix. The overall objective of the LAWS Project is to define, design, and implement an operational space based facility, LAWS, for accurate measurement of Earth wind profiles. Phase 1 addressed three major areas: (1) requirements definition; (2) instrument concepts and configurations; and (3) performance analysis. For the LAWS instrument concepts and configurations, the issues which press the technological state of the art are reliable detector lifetime and laser performance and lifetime. Lag angle compensation, pointing accuracy, satellite navigation, and telescope design are significant technical issues, but they are considered to be currently state of the art. The primary issues for performance analysis concern interaction with the atmosphere in terms of backscatter and attenuation, wind variance, and cloud blockage. The phase 1 tasks were formulated to address these significant technical issues and demonstrate the technical feasibility of the LAWS concept. Primary emphasis was placed on analysis/trade and identification of candidate concepts. Promising configurations were evaluated for performance, sensitivities, risks, and budgetary costs. Lockheed's baseline LAWS configuration is presented.
Diode pumped solid state lasers
NASA Astrophysics Data System (ADS)
Gluch, Richard P., Jr.
1990-05-01
I've come here today to share with you the experiences of an emerging company that has its hands around an emerging technology, and an interesting approach. And I'd like to make a few conmients today from a business aspect about the iaarketplace as they relate to our formulation of our market or business strategy. I'll share with you the direction on what the business strategy is and then trace with you some of the technical developments that are occurring at Laser Diode Products in St. Louis as they all relate directly to a customer requirernent.
Particulate contamination spectrometer. Volume 1: Technical report
NASA Technical Reports Server (NTRS)
Schmitt, R. J.; Boyd, B. A.; Linford, R. M. F.
1975-01-01
A laser particulate spectrometer (LPS) system was developed to measure the size and speed distributions of particulate (dusts, aerosols, ice particles, etc.) contaminants. Detection of the particulates was achieved by means of light scattering and extinction effects using a single laser beam to cover a size range of 0.8 to 275 microns diameter and a speed range of 0.2 to 20 meter/second. The LPS system was designed to operate in the high vacuum environment of a space simulation chamber with cold shroud temperatures ranging from 77 to 300 K.
Design and construction of a 76m long-travel laser enclosure for a space occulter testbed
NASA Astrophysics Data System (ADS)
Galvin, Michael; Kim, Yunjong; Kasdin, N. Jeremy; Sirbu, Dan; Vanderbei, Robert; Echeverri, Dan; Sagolla, Giuseppe; Rousing, Andreas; Balasubramanian, Kunjithapatham; Ryan, Daniel; Shaklan, Stuart; Lisman, Doug
2016-07-01
Princeton University is upgrading our space occulter testbed. In particular, we are lengthening it to 76m to achieve flightlike Fresnel numbers. This much longer testbed required an all-new enclosure design. In this design, we prioritized modularity and the use of commercial off-the-shelf (COTS) and semi-COTS components. Several of the technical challenges encountered included an unexpected slow beam drift and black paint selection. Herein we describe the design and construction of this long-travel laser enclosure.
Evaluating the coherence and time-domain profile of quantum cascade laser frequency combs
Burghoff, David; Yang, Yang; Hayton, Darren J.; ...
2015-01-01
Recently, much attention has been focused on the generation of optical frequency combs from quantum cascade lasers. We discuss how fast detectors can be used to demonstrate the mutual coherence of such combs, and present an inequality that can be used to quantitatively evaluate their performance. We discuss several technical issues related to shifted wave interference Fourier Transform spectroscopy (SWIFTS), and show how such measurements can be used to elucidate the time-domain properties of such combs, showing that they can possess signatures of both frequency-modulation and amplitude-modulation.
Kok, Jen; Chen, Sharon C A; Dwyer, Dominic E; Iredell, Jonathan R
2013-01-01
The integration of matrix-assisted laser desorption ionisation-time of flight mass spectrometry (MALDI-TOF MS) into many clinical microbiology laboratories has revolutionised routine pathogen identification. MALDI-TOF MS complements and has good potential to replace existing phenotypic identification methods. Results are available in a more clinically relevant timeframe, particularly in bacteraemic septic shock. Novel applications include strain typing and the detection of antimicrobial resistance, but these are not widely used. This review discusses the technical aspects, current applications, and limitations of MALDI-TOF MS.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elias, L.R.
1981-12-01
Results are presented of a three-dimensional numerical analysis of the radiation fields produced in a free-electron laser. The method used here to obtain the spatial and temporal behavior of the radiated fields is based on the coherent superposition of the radiated fields is based on the coherent superposition of the exact Lienard-Wiechert fields produced by each electron in the beam. Interference effects are responsible for the narrow angular radiation patterns obtained and for the high degree of monochromaticity of the radiated fields.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cheng Taiwang; Brown, Alex
2004-12-01
The interaction of a two-level dipolar molecule with two laser pulses, where one laser's frequency is tuned to the energy level separation (pump laser) while the second laser's frequency is extremely small (probe laser), is investigated. A dipolar molecule is one with a nonzero difference between the permanent dipole moments of the molecular states. As shown previously [A. Brown, Phys. Rev. A 66, 053404 (2002)], the final population transfer between the two levels exhibits a dependence on the carrier-envelope phase of the probe laser. Based on the rotating-wave approximation (RWA), an effective Hamiltonian is derived to account for the basicmore » characteristics of the carrier-envelope phase dependence effect. By analysis of the effective Hamiltonian, scaling properties of the system are found with regard to field strengths, pulse durations, and frequencies. According to these scaling properties, the final-state population transfer can be controlled by varying the carrier-envelope phase of the probe laser field using lasers with weak field strengths (low intensities) and relatively long pulse durations. In order to examine the possible roles of background states, the investigation is extended to a three-level model. It is demonstrated that the carrier-envelope phase effect still persists in a well-defined manner even when neighboring energy levels are present. These results illustrate the potential of utilizing excitation in dipolar molecules as a means of measuring the carrier-envelope phase of a laser pulse or if one can manipulate the carrier envelope phase, as a method of controlling population transfer in dipolar molecules. The results also suggest that the carrier-envelope phases must be taken into account properly when performing calculations involving pump-probe excitation schemes with laser frequencies which differ widely in magnitude.« less
Highly Efficient Nd:yag Lasers for Free-space Optical Communications
NASA Technical Reports Server (NTRS)
Sipes, D. L., Jr.
1985-01-01
A highly efficient Nd:YAG laser end-pumped by semiconductor lasers as a possible free-space optical communications source is discussed. Because this concept affords high pumping densities, a long absorption length, and excellent mode-matching characteristics, it is estimated that electrical-to-optical efficiencies greater than 5% could be achieved. Several engineering aspects such as resonator size and configuration, pump collecting optics, and thermal effects are also discussed. Finally, possible methods for combining laser-diode pumps to achieve higher output powers are illustrated.
Optically Pumped Atomic Rubidium Lasers: Two-Photon and Exciplex Excitation Mechanisms
2013-06-01
gain is very high with photon build-up times of 1−3.7 ns. Laser induced heating and subsequent condensation of alkali vapor in the heat pipe...encouragement during our time in classes, and recommendations while in the lab were invaluable. Finally, I want to thank the High Energy Laser Joint...intensity. The more non-traditional method is to use a single laser pulse to sketch out all needed energies. A photon build-up time was determined from
Model of the final borehole geometry for helical laser drilling
NASA Astrophysics Data System (ADS)
Kroschel, Alexander; Michalowski, Andreas; Graf, Thomas
2018-05-01
A model for predicting the borehole geometry for laser drilling is presented based on the calculation of a surface of constant absorbed fluence. It is applicable to helical drilling of through-holes with ultrashort laser pulses. The threshold fluence describing the borehole surface is fitted for best agreement with experimental data in the form of cross-sections of through-holes of different shapes and sizes in stainless steel samples. The fitted value is similar to ablation threshold fluence values reported for laser ablation models.
Filamentation due to the Weibel instability in two counterstreaming laser ablated plasmas
Dong, Quan -Li; Yuan, Dawei; Gao, Lan; ...
2016-05-01
Weibel-type filamentation instability was observed in the interaction of two counter streaming laser ablated plasma flows, which were supersonic, collisionless, and closely relevant to astrophysical conditions. The plasma flows were created by irradiating a pair of oppositely standing plastic (CH) foils with 1ns-pulsed laser beams of total energy of 1.7 kJ in two laser spots. Finally, with characteristics diagnosed in experiments, the calculated features of Weibel-type filaments are in good agreement with measurements.
Mazur, M M; Velikovskiy, D Yu; Mazur, L I; Pavluk, A A; Pozhar, V E; Pustovoit, V I
2014-07-01
The elastic and photo-elastic characteristics of four laser crystals KY(WO₄)₂, KGd(WO₄)₂, KYb(WO₄)₂, and KLu(WO₄)₂ are presented. The first pair was reported early, and the last two materials have been investigated for the first time. The full matrix of elastic constants of these monoclinic crystals has been determined. Also, acousto-optical figure of merit for all the basic geometries of isotropic diffraction has been measured. It is proved that potassium rare-earth tungstates has rather good acousto-optical properties and particularly can take place of fused silica in technical applications required high power laser radiation. All the results demonstrate good prospect of these optically bi-axial laser crystals for development of new effective acousto-optical devices. Copyright © 2014 Elsevier B.V. All rights reserved.
Laser Ranging to the Moon: How Evolving Technology Enables New Science
NASA Astrophysics Data System (ADS)
Faller, James
2010-03-01
Technological advances have long been the enabler of scientific progress. The invention of the laser is a prime example of this symbiotic relationship between technical progress and scientific advances. The laser, which today is omnipresent in each of our lives, made its first appearance during the time that I was a graduate student in Professor Dicke's group at Princeton. A major change occurring during that time period was that technology was transforming the study of gravitational physics from just a theoretical subject into also an experimental subject where one could hope to measure things using by-then-available laboratory technologies and techniques. During this same time, the idea for the lunar laser ranging experiment was born. The history and accomplishments of this experiment--a still ongoing experiment which is one of the real scientific triumphs of NASA's Apollo program--will be given.
Advanced Q-switched DPSS lasers for ID-card marking
NASA Astrophysics Data System (ADS)
Hertwig, Michael; Paster, Martin; Terbrueggen, Ralf
2008-02-01
Increased homeland security concerns across the world have generated a strong demand for forgery-proof ID documents. Manufacturers currently employ a variety of high technology techniques to produce documents that are difficult to copy. However, production costs and lead times are still a concern when considering any possible manufacturing technology. Laser marking has already emerged as an important tool in the manufacturer's arsenal, and is currently being utilized to produce a variety of documents, such as plastic ID cards, drivers' licenses, health insurance cards and passports. The marks utilized can range from simple barcodes and text to high resolution, true grayscale images. The technical challenges posed by these marking tasks include delivering adequate mark legibility, minimizing substrate burning or charring, accurately reproducing grayscale data, and supporting the required process throughput. This article covers the advantages and basic requirements on laser marking of cards and reviews how laser output parameters affect marking quality, speed and overall process economics.
Bian, Hao; Yang, Qing; Liu, Hewei; Chen, Feng; Du, Guangqing; Si, Jinhai; Hou, Xun
2013-03-01
Netlike or porous microstructures are highly desirable in metal implants and biomedical monitoring applications. However, realization of such microstructures remains technically challenging. Here, we report a facile and environmentally friendly method to prepare netlike microstructures on a stainless steel by taking the full advantage of the liquid-mediated femtosecond laser ablation. An unordered netlike structure and a quasi-ordered array of holes can be fabricated on the surface of stainless steel via an ethanol-mediated femtosecond laser line-scan method. SEM analysis of the surface morphology indicates that the porous netlike structure is in the micrometer scale and the diameter of the quasi-ordered holes ranges from 280 nm to 320 nm. Besides, we find that the obtained structures are tunable by altering the laser processing parameters especially scanning speed. Copyright © 2012 Elsevier B.V. All rights reserved.
Use of microgravity to improve the efficiency and power output of Nd-doped laser glasses
NASA Technical Reports Server (NTRS)
Ray, Chandra S.
1992-01-01
The objectives of this research are to: (1) obtain further evidence and understand the science for the reported improvement in chemical homogeneity in glasses prepared in microgravity; and (2) study the feasibility of improving the optical and fluorescence properties, particularly, the limit for Nd(+3) concentration quenching and threshold energy for laser action for laser glasses prepared in microgravity. Attention was directed to ground based investigation whose primary purpose was to determine the suitability and conditions for processing these laser glasses in space. This report describes that the scientific and technical information required for planning flight experiments for these glasses have been obtained, and the preparation for handling and analyzing post flight samples have also been taken. Instruments required for measuring the fluorescence properties of interest have been constructed. The optical and fluorescence properties for the glasses have been measured and made available for comparative property analysis.
Unresolved issues in excimer laser corneal surgery
NASA Astrophysics Data System (ADS)
Trokel, Stephen L.
1991-06-01
More than one hundred fifty clinical excimer laser units designed for corneal surgery have been developed and sold commercially. Manufacturers include Meditec Lasers in Germany, Summit Engineering, Taunton Technologies, and Visx in the United States, and Synthelabo in France. Furthermore a number of prototypes have been built in the USSR and other countries which are being investigated for their clinical use. While in the United States and Canada, substantial regulation of these devices has limited their distribution and use, sales in other parts of the world have been restricted only by market forces. Early clinical successes have created an enthusiasm for this new technology. In spite of this, substantial technical issues remain uncertain and have not been carefully studied. Indeed we have accepted certain parameters for on an almost serendipitous, empirical basis. It is a proper time to pause and consider the bases for these laser techniques.
Portuondo-Campa, E; Paschotta, R; Lecomte, S
2013-08-01
We report on the ultralow timing jitter of the 100 MHz pulse trains generated by two identical passively mode-locked diode-pumped solid-state lasers (DPSSLs) emitting at 1556 nm. Ultralow timing jitter of 83 as (integrated from 10 kHz to 50 MHz) for one laser has been measured with a balanced optical cross-correlator as timing discriminator. Extremely low intensity noise has been measured as well. Several measurement techniques have been used and show similar jitter results. Different possible noise sources have been theoretically investigated and compared to the measured jitter power spectral density. It is found that although the measured integrated jitter is quite low, it is still significantly above the quantum limit in the considered frequency span. Therefore, there is a substantial potential for technical improvements that could make passively mode-locked DPSSL outperform fiber lasers as source of microwaves with low phase noise.
Automated Laser Paint Stripping (ALPS) update
NASA Astrophysics Data System (ADS)
Lovoi, Paul
1993-03-01
To date, the DoD has played a major role in funding a number of paint stripping programs. Some technologies have proven less effective than contemplated. Others are still in the validation phase. Paint stripping is one of the hottest issues being addressed by the finishing industry since the Environmental Protection Agency (EPA) has mandated that chemical stripping using methylene chloride/phenolic type strippers be stopped. The DoD and commercial aircraft companies are hard-pressed to find an alternative. Automated laser paint stripping has been identified as a technique for removing coatings from aircraft surfaces. International Technical Associates (InTA) was awarded a Navy contract for an automated laser paint stripping system (ALPS) that will remove paint from metallic and composite substrates. For the program, which will validate laser paint stripping, InTA will design, build, test, and install a system for fighter-sized aircraft at both the Norfolk and North Island (San Diego) Aviation Depots.
Education and training for technicians in photonics-enabled technologies
NASA Astrophysics Data System (ADS)
Hull, Daniel M.; Hull, Darrell M.
2005-10-01
Within a few years after lasers were first made operational in 1960, it became apparent that rapid growth in the applications of this new technology in industry, health care, and other fields would require a new generation of technicians in laser/optics engineering. Technicians are the men and women who work alongside scientists and engineers in bringing their ideas, designs, and processes to fruition. In America, most highly qualified technicians are graduates of associate of applied science (AAS) programs in community and technical colleges (two-year postsecondary institutions). Curricula and educational programs designed to prepare technicians in laser/electro-optics technology (LEOT) emerged in the 1970s; today there are over 15 LEOT programs in the United States producing over 100 LEOT graduates each year.
Implementation status of the extreme light infrastructure - nuclear physics (ELI-NP) project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gales, S., E-mail: sydney.gales@eli-np.ro; Zamfir, N. V., E-mail: sydney.gales@eli-np.ro
2015-02-24
The Project Extreme Light Infrastructure (ELI) is part of the European Strategic Forum for Research Infrastructures (ESFRI) Roadmap. ELI will be built as a network of three complementary pillars at the frontier of laser technologies. The ELI-NP pillar (NP for Nuclear Physics) is under construction near Bucharest (Romania) and will develop a scientific program using two 10 PW lasers and a Compton back-scattering high-brilliance and intense gamma beam, a marriage of laser and accelerator technology at the frontier of knowledge. In the present paper, the technical description of the facility, the present status of the project as well as themore » science, applications and future perspectives will be discussed.« less
Efficacy of laser photoablative therapy and expandable metal stents for esophageal carcinoma
NASA Astrophysics Data System (ADS)
Balachandar, Gowra; Trowers, Eugene A.
2000-05-01
Malignant dysphagia is a serious condition in which 70% of patients die within one year, regardless of the treatment received. It provokes a rapid deterioration of a patient's physical condition and a significant worsening of quality of life. The surgical treatment of dysphagia is frequently complicated with technical difficulties, and often the tumors cannot be excised because of extensive invasion into adjacent structures. Furthermore, many patients are considered inoperable due to advanced age, associated diseases and malnutrition. Laser photoablative therapy coupled with expandable metal stents restores luminal patency in more than 80% of patients allowing them to eat liquids and soft foods. The efficacy of laser photoablative therapy and expandable metal stents for the palliation esophageal carcinoma will be critically reviewed.
NASA Technical Reports Server (NTRS)
McGill, Matthew J.; Starr, David OC. (Technical Monitor)
2002-01-01
The laser radar, or lidar (for light detection and ranging) is an important tool for atmospheric studies. Lidar provides a unique and powerful method for unobtrusively profiling aerosols, wind, water vapor, temperature, and other atmospheric parameters. This brief overview of lidar remote sensing is focused on atmospheric applications involving pulsed lasers. The level of technical detail is aimed at the educated non-lidar expert and references are provided for further investigation of specific topics. The article is divided into three main sections. The first describes atmospheric scattering processes and the physics behind laser-atmosphere interactions. The second section highlights some of the primary lidar applications, with brief descriptions of each measurement capability. The third section describes the practical aspects of lidar operation, including the governing equation and operational considerations.
NASA Astrophysics Data System (ADS)
Pupkova, Ludmila S.; Reznikov, Leonid L.; Bell, H.; Riazankin, V. P.
1995-05-01
Reflex therapy is one of numerous applications of low-energy laser radiation in medical treatment. The advantages of this therapy in comparison with traditional acupuncture include technical simplicity, absence of pain, and, as a consequence of the complete noninvasiveness of the procedure, the absence of risk of contracting AIDS or other infectious diseases. However, no definitive results have been published regarding the comparative effectiveness of the two approaches to reflex therapy. In view of the neurohumoral role in the curative effects of reflex therapy, we compared laser acupuncture and the traditional needle technique in relation to changes in the serum concentrations of the principal sexual and gonadotropic hormones in hypofertile men.
Final EDP Ti: sapphire amplifiers for ELI project
NASA Astrophysics Data System (ADS)
Chvykov, Vladimir; Kalashnikov, Mikhail; Osvay, Károly
2015-05-01
Recently several ultrahigh intensity Chirped Pulse Amplification (CPA) laser systems have reached petawatt output powers [1, 2] setting the next milestone at tens or even hundreds petawatts for the next three to ten years [3, 4]. These remarkable results were reached when laser amplifiers (opposite to Optical Parametric Amplification (OPA) [5]) were used as final ones and from them Ti:Sapphire crystals supposed to be the working horses as well in the future design of these laser systems. Nevertheless, the main limitation that arises on the path toward ultrahigh output power and intensity is the restriction on the pumping and extraction energy imposed by Transverse Amplified Spontaneous Emission (TASE) [6] and/or transverse parasitic generation (TPG) [7] within the large aperture of the disc-shape amplifier volume.
Ben, Shuai; Wang, Tian; Xu, Tongtong; Guo, Jing; Liu, Xueshen
2016-04-04
The carrier-envelop-phase (CEP) dependence of nonsequential double ionization (NSDI) of atomic Ar with few-cycle elliptically polarized laser pulse is investigated using 2D classical ensemble method. We distinguish two particular recollision channels in NSDI, which are recollision-impact ionization (RII) and recollision-induced excitation with subsequent ionization (RESI). We separate the RII and RESI channels according to the delay time between recollision and final double ionization. By tracing the history of the trajectories, we find the electron correlation spectra as well as the competition between the two channels are sensitively dependent on the laser field CEP. Finally, control can be achieved between the two channels by varying the CEP.
Laser safety programs in general surgery.
Lanzafame, R J
1994-06-01
General surgery represents a speciality where, while any procedure can be performed with lasers, there are no procedures for which the laser is the sine quo non. The general surgeon may perform a variety of procedures with a multitude of laser wavelengths and technologies. Laser safety in general surgery requires a multidisciplinary approach. Effective laser safety requires the oversight of the hospital's "laser usage committee" and "laser safety officer" while providing a workable framework for daily laser use in a variety of clinical scenarios simultaneously. This framework must be user-friendly rather than oppressive. This presentation will describe laser safety at the Rochester General Hospital, a tertiary care, community-based teaching hospital. The safety program incorporates the following components: input to physician credentialing and training, education and in-servicing of nursing and technical personnel, equipment purchase and maintenance, quality assurance, and safety monitoring. The University of Rochester general surgery residency training program mandates laser training during the PGY-2 year. This program stresses the safe use of lasers and provides the basis for graded hands-on experience during the surgical residency. The greatest challenge for laser safety in general surgery centers on the burgeoning field of minimally invasive surgery. Safety assurance must be balanced so as to maintain a safe operating-room environment while ensuring patient safety and the ability to permit the surgery to proceed efficiently. Safety measures for laparoscopic procedures must be sensitive to the needs of the surgical team while not providing confusing signals for the "gallery" observers. This task is critical for the safe operation of lasers in general surgery. Effective laser safety in general surgery requires constant vigilance tempered with sensitivity to the needs of the surgeon and the patient as laser technology and its applications continue to evolve.
NASA Astrophysics Data System (ADS)
Yin, Stuart (Shizhuo); Chao, Ju-Hung; Zhu, Wenbin; Chen, Chang-Jiang; Campbell, Adrian; Henry, Michael; Dubinskiy, Mark; Hoffman, Robert C.
2017-08-01
In this paper, we present a novel large capacity (a 1000+ channel) time division multiplexing (TDM) laser beam combining technique by harnessing a state-of-the-art nanosecond speed potassium tantalate niobate (KTN) electro-optic (EO) beam deflector as the time division multiplexer. The major advantages of TDM approach are: (1) large multiplexing capability (over 1000 channels), (2) high spatial beam quality (the combined beam has the same spatial profile as the individual beam), (3) high spectral beam quality (the combined beam has the same spectral width as the individual beam, and (4) insensitive to the phase fluctuation of individual laser because of the nature of the incoherent beam combining. The quantitative analyses show that it is possible to achieve over one hundred kW average power, single aperture, single transverse mode solid state and/or fiber laser by pursuing this innovative beam combining method, which represents a major technical advance in the field of high energy lasers. Such kind of 100+ kW average power diffraction limited beam quality lasers can play an important role in a variety of applications such as laser directed energy weapons (DEW) and large-capacity high-speed laser manufacturing, including cutting, welding, and printing.
NASA Technical Reports Server (NTRS)
Schulze, Norman; Cimolino, Marc; Guenther, Arthur; Mcminn, Ted; Rainer, Frank; Schmid, Ansgar; Seitel, Steven C.; Soileau, M. J.; Theon, John S.; Walz, William
1991-01-01
NASA has defined a program to address critical laser-induced damage issues peculiar to its remote sensing systems. The Langley Research Center (LaRC), with input from the Goddard Space Flight Center (GSFC), has developed a program plan focusing on the certification of optical materials for spaceflight applications and the development of techniques to determine the reliability of such materials under extended laser exposures. This plan involves cooperative efforts between NASA and optics manufacturers to quantify the performance of optical materials for NASA systems and to ensure NASA's continued application of the highest quality optics possible for enhanced system reliability. A review panel was organized to assess NASA's optical damage concerns and to evaluate the effectiveness of the LaRC proposed program plan. This panel consisted of experts in the areas of laser-induced damage, optical coating manufacture, and the design and development of laser systems for space. The panel was presented information on NASA's current and planned laser remote sensing programs, laser-induced damage problems already encountered in NASA systems, and the proposed program plan to address these issues. Additionally, technical presentations were made on the state of the art in damage mechanisms, optical materials testing, and issues of coating manufacture germane to laser damage.
IR lasers in a struggle against dangerous cosmic objects
NASA Astrophysics Data System (ADS)
Kuzyakov, Boris A.
2001-03-01
Humanity can struggle with the small dangerous cosmic objects in our time and its parameter knowledge are needed. A present paper deals with prospects for the perspective of the laser methods applications for a dangerous asteroids discovering and a remote sensing and for the course correction systems of the influence expedients. The cosmic IR lasers will be used for remote sensing measurement of the various cosmic objects parameters: dimensions are more than 50 m, velocity is more than 10 km/s. The laser methods have the good perspectives among a large fleet of diagnostics technical means. The more effective CO2-laser parameters were defined for the solar systems smaller bodies velocity analysis. The laser is supplied with modulated laser radiation and an automatic tuning optical system. The CO2-lidars are needed for the asteroids detections and remote sensing at the distances of 30,000 km to 1 Mkm. A laser Doppler anemometer method with adaptive selection is used. The power calculations were made for the various asteroids in a cosmic space. The possibilities are estimated for remote sensing and for the course correction systems of the influence expedients also. The such system must be good for the distances nearby 12600 km, as the asteroids velocity can be more than 70 km/s.
Bubbling in delay-coupled lasers.
Flunkert, V; D'Huys, O; Danckaert, J; Fischer, I; Schöll, E
2009-06-01
We theoretically study chaos synchronization of two lasers which are delay coupled via an active or a passive relay. While the lasers are synchronized, their dynamics is identical to a single laser with delayed feedback for a passive relay and identical to two delay-coupled lasers for an active relay. Depending on the coupling parameters the system exhibits bubbling, i.e., noise-induced desynchronization, or on-off intermittency. We associate the desynchronization dynamics in the coherence collapse and low-frequency fluctuation regimes with the transverse instability of some of the compound cavity's antimodes. Finally, we demonstrate how, by using an active relay, bubbling can be suppressed.
Optical trapping gold nanoparticles by a pulse laser
NASA Astrophysics Data System (ADS)
Liu, XiaoYu; Wang, Feng
2010-11-01
Gold nanoparticles are widely employed in nanomaterials, nanobiotechnology and health care, but generally they are considered difficult to trap stably. Compared with the continuous laser which is popular to the optical trapping, pulse laser has a relatively larger power in its work pulse, which is useful for trap particles. So this paper comprehensively analyzes the forces (the radiation forces, the gravitation, and the Brownian motion) on the gold nanoparticles in the optical tweezers formed by a pulse laser, through building up a mathematical model. Finally gets the dependence relation between the characteristics of the pulse laser and that of the gold nanoparticles.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Paranthaman, M. Parans; Sridharan, Niyanth; List, Fred A.
The technical objective of this technical collaboration phase I proposal is to fabricate near net-shaped permanent magnets using alloy powders utilizing direct metal deposition technologies at the ORNL MDF. Direct Manufacturing using the POM laser system was used to consolidate Nd 2Fe 14B (NdFeB) magnet powders into near net-shape parts efficiently and with virtually no wasted material as part of the feasibility study. We fabricated builds based on spherical NdFeB magnet particles. The results show that despite the ability to fabricate highly reactive materials in the laser deposition process, the magnetic coercivity and remanence of the NdFeB hard magnets ismore » significantly reduced. X-ray powder diffraction in conjunction with electron microscopy showed that the material experienced a primary Nd 2Fe 17B x solidification due to the undercooling effect (>60K). Consequently the presence of alpha iron phase resulted in deterioration of the build properties. Further optimization of the processing parameters is needed to maintain the Nd 2Fe 14B phase during fabrication.« less
The effect of cutting conditions on power inputs when machining
NASA Astrophysics Data System (ADS)
Petrushin, S. I.; Gruby, S. V.; Nosirsoda, Sh C.
2016-08-01
Any technological process involving modification of material properties or product form necessitates consumption of a certain power amount. When developing new technologies one should take into account the benefits of their implementation vs. arising power inputs. It is revealed that procedures of edge cutting machining are the most energy-efficient amongst the present day forming procedures such as physical and technical methods including electrochemical, electroerosion, ultrasound, and laser processing, rapid prototyping technologies etc, such as physical and technical methods including electrochemical, electroerosion, ultrasound, and laser processing, rapid prototyping technologies etc. An expanded formula for calculation of power inputs is deduced, which takes into consideration the mode of cutting together with the tip radius, the form of the replaceable multifaceted insert and its wear. Having taken as an example cutting of graphite iron by the assembled cutting tools with replaceable multifaceted inserts the authors point at better power efficiency of high feeding cutting in comparison with high-speed cutting.
Seattle To Portland Inter-City ITS Corridor Study And Communications Plan, Final Report
DOT National Transportation Integrated Search
1996-03-01
THIS DOCUMENT IS THE FINAL REPORT PRESENTING THE SEATTLE TO PORTLAND INTELLIGENT TRANSPORTATION SYSTEM (ITS) EARLY DEPLOYMENT PLAN. THE FINAL REPORT SYNTHESIZES INFORMATION FROM TECHNICAL MEMORANDUMS 1 THROUGH 5; INCLUDING EXISTING AND FUTURE CONDITI...
Laser Shot Peening Final Report CRADA No. TC-02059-03
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stuart, B. C.; Hackel, L.
This was a collaborative effort between The Regents of the University of California, Lawrence Livermore National Laboratory (LLNL) and Metal Improvement Company, Inc. (MIC), to further develop the laser shot peening technology. This project had an emphasis on laser development and government and military applications including DOE’s natural gas and oil technology program (NGOTP), Yucca Mountain Project (YMP), F-22 Fighter, etc.
X-Ray Laser Program Final Report for FY92
1993-07-01
also produced population inversion. Ultra- intense , femtosecond- pulsed laboratory lasers ranging from the ultraviolet to the infrared represent an...with pulse lengths of 650 femtoseconds normally Incident on a 2p. thick planar aluminum slab. Comparisons are made for two laser Intensities , two...prepulse is subsequently irradiated by the main high intensity pulse . The persistence of the heliumlike ground state raises the possibility that a photon
Benchmark Analysis of Career and Technical Education in Lenawee County. Final Report.
ERIC Educational Resources Information Center
Hollenbeck, Kevin
The career and technical education (CTE) provided in grades K-12 in the county's vocational-technical center and 12 local public school districts of Lenawee County, Michigan, was benchmarked with respect to its attention to career development. Data were collected from the following sources: structured interviews with a number of key respondents…
For the safe use of lasers in educational institutions: elementary through university
NASA Astrophysics Data System (ADS)
Seeber, Fredrick P.
1995-10-01
The use of lasers by the academic community continues to dramatically escalate. Academia is inundated with a profusion of lasers, each with a diverse function. Traditional departments such as biology, chemistry, and physics have introduced the use of lasers as an essential element of tutelage. Even the more distinctive departments such as Cancer Research, Civil Engineering, Earth and Planetary Science, Plasma Fusion, Spectroscopy, and so forth, have incorporated the laser in the composition of their educational mechanism. The literature indicates most ocular accidents happen during alignment procedures, which is an everyday activity for educational laboratories. Also, the improper use of laser safety eye wear is a major area of concern for laser safety in education institutions. More Class II, III, and IV lasers are used in universities, colleges, laser electro-optic technical colleges and high schools than probably any other area: for teaching, research, laboratory experiments, and demonstrations. Relatively large numbers of students work in laboratory groups in confined area, with various lasers of different wavelengths in the same laboratory. Open cavity and beam paths of Class IV lasers are common in these environments. Most educational institutions do not have laser safety officers or standard operation procedures. This paper will discuss the development of a new laser safety standard by an ANSI ad-hoc committee and by the executive committee of the ANSI Z-136 intended to provide adequate, reasonable, and practical guidance for educators, students, and spectators found in classrooms, lecture halls, and laboratories associated with universities, colleges, high, and elementary schools.