Download or read book Nonlinear Optical Effects an Optical Power Limiter written by Stanford University. Stanford Electronics Laboratories and published by . This book was released on 1962 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nonlinear materials for optical power limiting written by Hampus Lundén and published by Linköping University Electronic Press. This book was released on 2019-05-13 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: High power laser pulses can be a threat to optical sensors, including the human eye. Traditionally this threat has been alleviated by colour filters that block radiation in chosen wavelength ranges. Colour filters’ main drawback is that they block radiation regardless of it being useful or damaging, information is lost for wavelengths at which the filter is active. Protecting the entire wavelength range of a sensor would block or strongly attenuate the radiation needed for the operation of the sensor. Sol-gel glasses highly doped with optically non-linear chromophores have previously shown high optical quality in combination with efficient optical power limiting (OPL) through reverse saturable absorption (RSA). These filters transmit visible light unless the light fluence is above a certain threshold. A key design consideration of laser protection filters is linear absorption in relation to the threshold level. A high linear absorption means that the user’s view is degraded by the filter. To model the photokinetics of RSA chromophores, the five-level population model is widely used. It consists of three singlet and two triplet levels. Model parameters relevant for OPL performance include linear absorption cross-sections, two-photon absorption (2PA) cross-sections, lifetimes, quantum yields and inter-system-crossing (ISC) times. The dominant design paradigm is to have a highly absorbing and long-lived triplet state that is quickly populated by ISC during the beginning of a laser pulse. To simultaneously achieve a lower threshold and linear absorption a vast number of materials for self-activated filters were evaluated, either as bulk glasses or solutions. An f/5 setup was used to evaluate their OPL performance while several photophysical measurements were performed to gain an understanding of system behaviour. The first three series of methyltriethoxysilane (MTEOS) Sol-Gel glasses were doped with gold nanoparticles either solely, or with one of two Pt-acetylide chromophores. One with shorter conjugated ligands, the second with similar but longer conjugated ligands. Finally, a series of multi-branched fluorene chromophores were evaluated in solution. Their central moiety was either an organic benzene unit or an ISC promoter in the form of para-dibromobenzene or a platinum(II)-alkynyl unit. For the gold nanoparticle doped glasses, the lower performance Pt-acetylide with short ligands had its OPL threshold lowered at 600nm while the glasses doped with only gold nanoparticles showed no OPL at all. Secondly, the enhancement was most pronounced for very low gold nanoparticle concentrations. While gold nanoparticles alone showed good OPL performance at 532 nm, at this wavelength neither Pt-acetylide showed an obvious OPL enhancement beyond linear absorption losses from codoping with gold nanoparticles. The improved OPL performance at 600 nm was attributed to stronger 2PA, by electric field enhancement from the gold nanoparticles. The lack of detectable OPL improvement for 532 nm and for the higher performance Pt-Acetylide chromophore with long ligands were qualitatively explained by a lower sensitivity to 2PA on system performance. A degraded performance from linear absorption by excess nanoparticles in front of the focus explained the weakening of the enhancement at higher gold nanoparticle concentrations. All three fluorene chromophores, including the chromophore without a central ISC promoter, showed broadband OPL through the visible spectrum. The OPL performance of the two chromophores with ISC promoters was expected considering their transient absorption at microsecond time-scales. For the fluorene chromophore without an ISC-promoter, ultra-fast transient absorption was used to identify singlet excited state absorption as the source of the OPL performance. Both of these series of experiments demonstrate how a simplistic view of simply increasing desired photophysical parameters, e.g. effective 2PA cross-section or ISC quantum yield, do not always result in a noticeable increase in system performance. By employing numerical population models it was possible to identify which parameters had the highest impact on OPL performance. Laserpulser med hög effekt kan vara ett hot mot optiska sensorer, inklusive det oskyddade ögat. Traditionellt har detta hot hanterats med färgfilter som stoppar strålning inom valda våglängdsband. Färgfilters huvudsakliga begränsning ligger i att de tar bort strålning oberoende av om den är användbar eller skadlig, att information försvinner för de våglängder filtret skyddar för. Skydd över hela det våglängdsband en sensor verkar i skulle stoppa eller kraftigt försvaga strålningen som sensorn behöver för att fungera. Sol-gel glas högdopade med optiskt icke-linjära molekyler har tidigare visat hög optisk kvalité i kombination med en effektiv optisk effektbegränsning (OPL) via omvänd blekning (RSA). Dessa filter transmitterar synligt ljus så länge ljusets fluens (pulsenergi per area [J cm-2]) inte ligger över en viss begränsningsnivå. En nyckelfaktor i designen av laserskyddsfilter är linjärabsorption kontra begränsningsnivå. Genom att öka kromoforkoncentrationen så kan begränsningsnivån sänkas till kostnad av ökad linjärabsorption. Detta betyder dock att användarens omvärldsuppfattning genom filtret riskerar att minska. För att modellera fotokinetiken av RSA-molekyler har femnivåpopulationsmodellen varit vida använd. Den består av tre singlet-nivåer och två tripletnivåer. Modellparametrar relevanta för OPL-prestanda innefattar kvantverkningsgrader, olika övergångars linjärabsorptionstvärsnitt, tvåfotonsabsorptionstvärsnitt och livstider samt halveringstider för överföring mellan singlet och triplettillstånd. Den dominanta designparadigmen är att ha ett hög- absorberande och långlivat tripletläge som snabbt populeras i början av en laserpuls. För att samtidigt uppnå en lägre begränsningsnivå och lägre linjärabsorption utvärderades ett flertal självaktiverade filter, antingen i form av glas eller i vätskelösning. En f/5-uppställning användes för att utvärdera deras OPLprestanda medan en mängd fotofysiska mätningar utfördes för att få en förståelse för deras systembeteende. De tre första serierna av MTEOS Sol-Gel glas var dopade med guldnanopartiklar antingen enbart, eller med en av två Pt(II)-acetylidmolekyler. Den första hade kortare konjugerade ligandarmar, den andra var liknande men hade längre ligandarmar. Slutligen utvärderades en serie av flerarmade flourenmolekyler i vätskelösning. Deras centrala enhet bestod antingen av en organisk bensenring eller en ISC-gynnare i form av para-dibromobensen eller en Pt(II)-acetylidenhet. Guldnanopartiklarna kunde förstärka OPL-prestandan för enbart den mindre effektiva korta Pt(II)-acetylidmolekylen på 600nm men ej 532nm. Filtren dopade med enbart guldnanopartiklar visade god prestanda på 532nm men ingen på 600nm. Alla tre fluorenmolekyler visade OPL genom det synliga spektrat, även den molekylen utan ISC-gynnare. Både dessa serier experiment demonstrerar hur ett förenklat angreppsätt med att enbart öka eftertraktade fotofysiska parametrar, t.ex. effektivt 2PA-tvärsnitt eller ISC-kvantverkningsgrad, inte alltid resulterar i märkbart ökad systemprestanda. Genom att använda numeriska populationsmodeller visas hur det är möjligt att identifiera vilka parametrar som har den största inverkan på OPL-prestanda.
Download or read book Proceedings of the First International Workshop on Optical Power Limiting written by Francois Kajzar and published by CRC Press. This book was released on 1999 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nonlinear Optical Liquids and Power Limiters written by Christopher M. Lawson and published by SPIE-International Society for Optical Engineering. This book was released on 1997 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laser Induced Damage In Optical Materials 1981 written by Harold E. Bennett and published by ASTM International. This book was released on 1983 with total page 656 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Materials for Optical Limiting Volume 374 written by Robert Crane and published by . This book was released on 1995-11-20 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: The advent of lasers has made possible a number of optical-based systems and applications such as the compact disc (CD), laser printers, fiber optic communications, laser surgical instruments, etc. Unfortunately, while lasers permit these diverse applications, safety concerns must be addressed. A solution being pursued is the development of optical limiter materials that transmit at low intensities while changing their optical characteristics, e.g. absorption or index of refraction, when exposed to the laser's higher irradiances. Topics covered in this book relate directly to the computational design and synthesis of new optical molecules. Research on the design of limiter devices is also featured. Materials addressed include liquid crystals, organic polymers, organic dyes, C60, colloidal arrays and suspensions, transition metal oxides, semiconductors and photorefractive oxides. Topics include: modelling and solid state optical limiters; thin film and solid state optical limiters; saturable and reverse-saturable absorbers; liquid optical limiters and liquid crystalline and other optical limiters.
Download or read book Materials for Optical Switches Isolators and Limiters written by M. J. Soileau and published by . This book was released on 1989 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nanotechnology for Telecommunications written by Sohail Anwar and published by CRC Press. This book was released on 2017-12-19 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt: With its unique promise to revolutionize science, engineering, technology, and other fields, nanotechnology continues to profoundly impact associated materials, components, and systems, particularly those used in telecommunications. These developments are leading to easier convergence of related technologies, massive storage data, compact storage devices, and higher-performance computing. Nanotechnology for Telecommunications presents vital technical scientific information to help readers grasp issues and challenges associated with nanoscale telecommunication system development and commercialization—and then avail themselves of the many opportunities to be gleaned. This book provides technical information and research ideas regarding the use of nanotechnology in telecommunications and information processing, reflecting the continuing trend toward the use of optoelectronics. Nanotech will eventually lead to a technology cluster that offers a complete range of functionalities for systems used in domains including information, energy, construction, environmental, and biomedical. Describing current and future developments that hold promise for significant innovations in telecommunications, this book is organized to provide a progressive understanding of topics including: Background information on nanoscience and nanotechnology Specific applications of nanotechnology in telecommunications Nanostructured optoelectronic materials MEMS, NEMS, and their applications in communication systems Quantum dot Cellular Automata (QCA) and its applications in telecommunication systems How nonohmic nonlinear behavior affects both digital and analog signal processing Concepts regarding quantum switching and its applications in quantum networks The scale of the physical systems that use nanoscale electronic devices is still large, and that presents serious challenges to the establishment of interconnections between nanoscale devices and the outside world. Also addressing consequent social implications of nanotech, this book reviews a broad range of the nano concepts and their influence on every aspect of telecommunications. It describes the different levels of interconnections in systems and details the standardized assembly process for a broad specrum of micro-, nano-, bio-, fiber-optic, and optoelectronic components and functions. This book is a powerful tool for understanding how to harness the power of nanotech through integration of materials, processes, devices, and applications.
Download or read book Functional Metallosupramolecular Materials written by John George Hardy and published by Royal Society of Chemistry. This book was released on 2015-07-13 with total page 417 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is great interest in metallosupramolecular materials because of their use in magnetic, photonic and electronic materials. Functional Metallosupramolecular Materials focuses on the applications of these materials covering the chemistry underlying the synthesis of a variety of ligands to coordinate various metal ions and the generation of 2D and 3D materials based on these constructs. The book starts by looking at different metallosupramolecular systems including naturally occurring functional metallosupramolecular materials; DNA-based metallosupramolecular materials; metallopolymers; metallogels as well as functional materials based on MOFs. Subsequent chapters then systematically cover the different applications such as molecular computation, spin-crossover, light harvesting and as photocatalysts for the production of solar fuels. The book provides an overview of functional metallosupramolecular materials that will be of interest to graduate students, academics and industrial chemists interested in supramolecular chemistry, materials science and the materials applications.
Download or read book Laser Induced Damage in Optical Materials written by and published by . This book was released on 1983 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Electronics Handbook written by Jerry C. Whitaker and published by CRC Press. This book was released on 2018-10-03 with total page 2640 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the ten years since the appearance of the groundbreaking, bestselling first edition of The Electronics Handbook, the field has grown and changed tremendously. With a focus on fundamental theory and practical applications, the first edition guided novice and veteran engineers along the cutting edge in the design, production, installation, operation, and maintenance of electronic devices and systems. Completely updated and expanded to reflect recent advances, this second edition continues the tradition. The Electronics Handbook, Second Edition provides a comprehensive reference to the key concepts, models, and equations necessary to analyze, design, and predict the behavior of complex electrical devices, circuits, instruments, and systems. With 23 sections that encompass the entire electronics field, from classical devices and circuits to emerging technologies and applications, The Electronics Handbook, Second Edition not only covers the engineering aspects, but also includes sections on reliability, safety, and engineering management. The book features an individual table of contents at the beginning of each chapter, which enables engineers from industry, government, and academia to navigate easily to the vital information they need. This is truly the most comprehensive, easy-to-use reference on electronics available.
Download or read book MEMS and MOEMS Technology and Applications written by P. Rai-Choudhury and published by SPIE Press. This book was released on 2000 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: The silicon age that led the computer revolution has significantly changed the world. The next 30 years will see the incorporation of new types of functionality onto the chip-structures that will enable the chip to reason, to sense, to act and to communicate. Micromachining technologies offer a wide range of possibilities for active and passive devices. Recent developments have produced sensors, actuators and optical systems. Many of these technologies are based on surface micromachining, which has evolved from silicon integrated circuit technology. This book is written by experts in the field. It contains useful details in design and processing and can be utilized as a reference book or as a textbook.
Download or read book Official Gazette of the United States Patent and Trademark Office written by and published by . This book was released on 1999 with total page 826 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optical Nonlinearities in Chalcogenide Glasses and Their Applications written by A. Zakery and published by Springer Science & Business Media. This book was released on 2007-06-19 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews techniques used to characterize non-linear optical constants of chalcogenide glasses in bulk or thin films, and presents the properties of many chalcogenide systems. A range of applications of these glasses are surveyed, including ultra-fast switching, optical limiting, second harmonic generation and electro-optic effects. Also addressed are suitability of chalcogenide films in all-optical integrated circuits, fabrication of rib as well as ridge waveguides and of fiber gratings.
Download or read book Space Division Multiplexing in Optical Communication Systems written by Masataka Nakazawa and published by Springer Nature. This book was released on 2022-08-29 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents new frontiers in data communication. To transcend the physical limitations of current optical communication technologies, totally new multiplexing schemes beyond TDM/WDM, novel transmission optical fibers handling well above Pbit/s capacity, and next-generation optical submarine cable systems will need to be developed. The book offers researchers working at the forefront, as well as advanced Ph.D. students in the area of optical fiber communications systems and related fields, an essential guide to state-of-the-art optical transmission technologies. It explores promising new technologies for the exabit era; namely, the three “M technologies”: multi-level modulation, multi-core fiber, and multi-mode control.
Download or read book Laser Abstracts written by Ahmad K. Kamal and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotated Bibliography.- List of Bibliographies.- Author Index.
Download or read book Semiconductors and Semimetals written by and published by Academic Press. This book was released on 1985-04-25 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductors and Semimetals
