A summary of the spectral loss for five of the six subcategories of fibers listed in Fig. It has become a powerful, fast, and non-destructive tool for food quality analysis and control. As a result, clear interference peaks are observed in both the visible and mid-infrared regions. The absorptions shown for the hollow are not due to impurities; rather they are due to effects resulting from the thin-film coatings used to make the guides. Stable fabrication and better reproduction were also observed by using the new coating method. The most common way of doing this is using airholes. In this review, we discuss the basic considerations of advanced techniques for soft glass fiber and fiber preform as well as three key issues among them.
At the State Department, Jim served as a science advisor within the Bureau of Security and Nonproliferation and helped to establish international controls for lasers and detectors. Not only did they not transmit sufficiently far into the infrared, but they were also too brittle. The characteristics that were obtained make these waveguides promising for the delivery of high-power laser pulses in medical as well as other applications. This paper reviews results of research on new types of optical fibres: bismuthdoped active fibres, multicore fibres and hollow-core fibres, which can be used as key components of systems that ensure further increase in optical information transfer rate. Beginning in 1977, it has been awarded annually in recognition of outstanding engineering or scientific accomplishments in optics, electro-optics, or photographic technologies or applications. Glass composition and key physical properties -- 5. The diameters of the fiber and the gas cell are smaller than 1.
So far, only limited success has been achieved in the development of such fibers, due to the lack of suitable materials that are transparent in this spectral range. He has authored more than 170 articles, book chapters, and books. Harrington Jim , born May 5, 1942, son of George and Evelyn Harrington, passed away on June 20, 2018. Bahr, and sister Donna H. A fiber-optic respiration sensor is capable of detecting carbon dioxide in exhalation of a patient using the infrared absorption characteristics of carbon gases. Other chalcogenide glasses -- ch. The spectral properties of chalcogenide glass 0.
For the experiments we utilized three mid-infrared quantum cascade lasers with different emission wavelength, which were coupled into the waveguides using lenses with focal lengths in the range 25-76 mm. The E-mail message field is required. Specifically Jim and his students invented the hollow glass waveguide, one of the most actively licensed technologies within Rutgers. Bahr William , grandsons William G. With nested negative curvature fibers, chalcogenide fibers have losses that are lower than those of silica fibers at wavelengths larger than 2 μm. We demonstrate the effectiveness of such an approach by fabricating a broad-band, low-loss hollow waveguide in the 10-μm region and measuring its transmission around a 300 bend.
The bore sizes of the hollow-sapphire waveguides were 1070 and 790 μm, and the hollow-glass waveguide had a bore of 700 μm. Emission and absorption spectra and lifetimes of energy levels have been measured. The resulting equations and simulations reveal that the emergence of zero group velocity dispersion in anti-resonant fibers is fundamentally associated with the adjacent annulus resonance which can be adjusted mainly via the glass thickness of the anti-resonant elements. The waveguides ranged in length from 1. Therefore, there is still a lot of opportunity for these technologies to be developed and to be able to miniaturize optical devices with high functionality and integration. As long as the unclad fiber does not come in contact with an absorbing medium, the fiber can operate reasonably well, as there will be very little leakage of from the core to the surrounding air. These fibers possess unique optical, mechanical, and physical properties, enabling many technologies.
In 1973 Jim moved to Huntsville, Alabama, where he began his academic career teaching for three years as Assistant Professor of Physics at the University of Alabama. The photonic crystal fibers were characterized by near-field and far-field measurements and they demonstrated a single-mode behavior with relatively low losses and a large mode area, in agreement with our simulations. However, the development of high-power single-frequency fiber lasers is constrained greatly by the lack of high-gain optical fiber and components. Fluoride glasses are notable for their extended transparency out to infrared wavelengths, with ultra-low loss of 0. The recipient s shall have made an exceptional contribution to the advancement of relevant technology. Mechanical properties of fiber -- 4.
While these glasses had, in fact, been made into fiber some years earlier, they turned out to be unsuitable for the army application. Mechanical properties of hollow waveguides -- ch. Chalcogenide glass fibers based on sulfide, selenide, telluride and their rare earth doped compositions are being actively investigated worldwide. He is also the inventor of the hollow sapphire and alumina waveguides, used today in certain laser surgical applications. With full examination of this rapidly growing field, this book: Combines many different aspects and applications into one comprehensive volume Discusses how chemical imaging techniques have expanded greatly in terms of instruments and applications, but have lagged in general awareness among scientists and industries that would benefit the most from them Describes chemical imaging uses in key areas—biomedical, pharmaceutical, food, and polymer research Has chapters that outline hardware and instrumentation for the different methods of chemical imaging Encapsulating analytic methods without complicating the subject matter, this book shows where chemical imaging has been successfully applied, inspiring researchers to cultivate the exciting capabilities rooted within this powerful and multifaceted technology. A miniature gas cell that is comprised of a stainless-steel tube with slots for gas inlet and a micro-mirror is fabricated.
The theoretical aspects of solid-core fibers and hollow waveguides are covered in Chapters 2 and 3, respectively. The silica-glass cap with a wall thickness of 400 microm shows a transmission loss of 0. The use of a laser in surgical procedures involving the soft tissues is advantageous due to its sterile and hemostatic nature. Its use as an incisional tool with very little to no carbonization is shown in this study. Each of these chapters is designed to familiarize the reader not only with the properties of each fiber but also the limitations and shortcomings of each fiber type. At about the same time, the U.
The bending strengths of these fibers have been measured and are satisfactory for short length applications. Such fibres, however, have not found wide application, presumably because of the technical problems with their fabrication and the comparatively high optical loss in them ~0. Death notice for the town of: Elizabeth, state: New Jersey death notice James A Harrington May 5 1942 June 20 2018 age 76 obituary notice James A Harrington May 5 1942 June 20 2018 age 76 Post a message of sympathy, your message will be posted publicly on the page Your email address will not be published. After he completed his fellowship, Jim returned to Rutgers but continued to serve the State Department for an additional five years in an advisory capacity. Techniques for coating hollow glass fibers with layers of silver and cyclic olefin polymer have been developed for low-loss delivery of infrared laser light as well as a visible pilot beam.
The active length along this fibre employed for sensing is 3 cm. Mechanical properties of fiber -- 5. The reason that they are not is that the fibers contain impurities and imperfections, which give rise to a large extrinsic and scattering. In 1989 Jim resumed his academic career at Rutgers University where he attained the rank of Distinguished Professor in 1998, and taught and conducted research for 29 years. This site is like a library, you could find million book here by using search box in the widget.