Download or read book Absolute Distance Interferometry Capable of Long term High Frequency Measurements of Fast Targets written by Andrew James Lancaster and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Self mixing Interferometry for Absolute Distance Measurement written by Mengkoung Veng (docteur en photonique).) and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Self-mixing Interferometry has been studied extensively in the last five decades in various sensing applications. Sensors under the SMI technique have the laser diode as the light source, the interferometer, and the detector. The light from the laser diode propagates towards a distant target where it is partially reflected or back-scattered before being re-injected into the active cavity of the laser. When the laser diode experiences the external optical feedback, the reflected light imprinted with information from the distant target or from the external cavity medium induces perturbation to the operating parameters of the laser. For SMI measurement sensors such as harmonic motion and absolute distance applications, the fringe counting method is basically used to determine the target's displacement and distance respectively. Two different approaches to modelling the SMI phenomenon have been developed: the three-mirror cavity and the perturbation of the rate equation. The single equation that describes the phase condition imposed by the optical feedback is usually referred to as the excess phase equation. One of the most important and most useful parameters in the excess phase equation is the feedback parameter C as it can be used to qualitatively categorize the regime of the laser under optical feedback. When the feedback level C 1, the laser behaviour is stable. On the other hand, when the feedback level C 1, more complex phenomena are observed such as hysteresis effect, presence of multiple emission frequencies (including the unstable frequencies), apparent splitting of the emission line due to mode hopping and fringe disappearance phenomenon. The fringes disappearance phenomenon in the self-mixing interferometry occurs whenever the external round-trip phase at free-running state is modulated by either external modulation such as external cavity length changes or internal modulation when the laser injection current is modulated with a high back-scattered light power. This phenomenon has been observed by many authors for harmonic motion or vibration application and more recently in the case of the absolute distance measurement scheme when the laser injection current is modulated in the triangle waveform. This phenomenon is highly dependent on the feedback parameter C and it is described in detail based on the coupled cavity model. The primary cause for fringes disappearance is demonstrated to be the expansion of the excess phase equation stable solutions range with the increment of the parameter C, thus reducing the number of stable solutions for a given phase stimulus. This new approach in the modelling of the fringe disappearance phenomenon allows determination of the C values for which a pair of fringes are expected to disappear and as a consequence correlates the number of missing fringes to the value of C. This approach is validated both by a behavioural model of the laser under optical feedback and by a series of measurements in the SMI absolute distance configuration.
Download or read book Absolute Distance Metrology Using Frequency Swept Lasers written by Matthew Stuart Warden and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes and evaluates two new interferometric distance measurement methods based upon the well known method of Frequency Scanning Interferometry (FSI). These new methods are known as Dynamic FSI and Cascaded FSI. Dynamic FSI addresses the two problems, commonly seen in previous FSI implementa- tions, of not being able to measure a moving target and having a slow measurement rate. This method measures stationary and moving targets equally well, and can determine the distance to the target at all times during the measurement, in contrast to previous methods, which obtain only a single measured length from a measurement process which can take up to a second to make. Cascaded FSI was developed with the aim of increasing the accuracy and precision of FSI. This method allows for measurements with precision equal to that of displacement interferometry, and also provides a way of measuring length relative to the frequencies of atomic absorption lines, which are inherently more stable length references than a physical length artefact.
Download or read book Handbook of Forensic Photography written by Sanford Weiss and published by CRC Press. This book was released on 2022-06-20 with total page 731 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handbook of Forensic Photography is the most-comprehensive, definitive reference for the use of photography in the capture and presentation of forensic evidence. The intent is to inform the reader about the most complete and up-to-date methods to capture and reproduce images that most accurately represent the evidence. With the rise in importance of forensic science, crime and accident scene documentation has likewise increased in importance—not the least of which has been forensic photography. The need to use accepted practice and protocols to guarantee the authenticity of images for evidence documentation is paramount for using it in court. And as with any discipline, there is an art to the science of forensic photography. Contributing authors from various backgrounds—each experts in their field—have provided numerous case examples, best practices, and recommendations for recognizing, recording, and preserving evidence using cameras and the latest digital image technology, including video and other imaging technologies. Chapters present such topics as videography, drone photography, underwater photography, crime scene photography, autopsy photographs, fire documentation, forensic odontology, and more. The book closes with coverage of courtroom displays, presenting imaging evidence and expert witness testimony in the courtroom. Handbook of Forensic Photography is a must-have reference for experienced crime scene photographers, death and crime scene investigators, police, and forensic professionals—including medical examiners, odontologists, engineers, and forensic anthropologists—who frequently need to capture investigative photographs in the course of investigations.
Download or read book From Quantum To Cosmos Fundamental Physics Research In Space written by Slava G Turyshev and published by World Scientific. This book was released on 2009-05-21 with total page 764 pages. Available in PDF, EPUB and Kindle. Book excerpt: Space-based laboratory research in fundamental physics is an emerging research discipline that offers great discovery potential and at the same time could drive the development of technological advances which are likely to be important to scientists and technologists in many other different research fields. The articles in this review volume have been contributed by participants of the international workshop “From Quantum to Cosmos: Fundamental Physics Research in Space” held at the Airlie Center in Warrenton, Virginia, USA, on May 21-24, 2006. This unique volume discusses the advances in our understanding of fundamental physics that are anticipated in the near future, and evaluates the discovery potential of a number of recently proposed space-based gravitational experiments. Specific research areas covered include various tests of general relativity and alternative theories, search of physics beyond the Standard Model, investigations of possible violations of the equivalence principle, search for new hypothetical long- and short-range forces, variations of fundamental constants, tests of Lorentz invariance and attempts at unification of the fundamental interactions. The book also encompasses experiments aimed at the discovery of novel phenomena, including dark matter candidates, and studies of dark energy.
Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 2240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Interferometry and Synthesis in Radio Astronomy written by A. Richard Thompson and published by Wiley-Interscience. This book was released on 1986-04-28 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: A unified description of the theory and practice of radio interferometry and synthesis mapping techniques as they apply to astronomy and geology. Beginning with an historical review, it goes on to provide a detailed description of all aspects of radio inferometry, from basic principles through instrumental design to data reduction. Over 450 original papers and monographs are cited.
Download or read book NASA Technical Memorandum written by and published by . This book was released on 1963 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laser Radar written by National Research Council and published by National Academies Press. This book was released on 2014-03-14 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: In today's world, the range of technologies with the potential to threaten the security of U.S. military forces is extremely broad. These include developments in explosive materials, sensors, control systems, robotics, satellite systems, and computing power, to name just a few. Such technologies have not only enhanced the capabilities of U.S. military forces, but also offer enhanced offensive capabilities to potential adversaries - either directly through the development of more sophisticated weapons, or more indirectly through opportunities for interrupting the function of defensive U.S. military systems. Passive and active electro-optical (EO) sensing technologies are prime examples. Laser Radar considers the potential of active EO technologies to create surprise; i.e., systems that use a source of visible or infrared light to interrogate a target in combination with sensitive detectors and processors to analyze the returned light. The addition of an interrogating light source to the system adds rich new phenomenologies that enable new capabilities to be explored. This report evaluates the fundamental, physical limits to active EO sensor technologies with potential military utility; identifies key technologies that may help overcome the impediments within a 5-10 year timeframe; considers the pros and cons of implementing each existing or emerging technology; and evaluates the potential uses of active EO sensing technologies, including 3D mapping and multi-discriminate laser radar technologies.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1973 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optical Interferometry written by Alexandr Banishev and published by BoD – Books on Demand. This book was released on 2017-02-15 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical methods of measurements are the most sensitive techniques of noncontact investigations, and at the same time, they are fast as well as accurate which increases reproducibility of observed results. In recent years, the importance of optical interferometry methods for research has dramatically increased, and applications range from precise surface testing to finding extrasolar planets. This book covers various aspects of optical interferometry including descriptions of novel apparatuses and methods, application interferometry for studying biological objects, surface qualities, materials characterization, and optical testing. The book includes a series of chapters in which experts share recent progress in interferometry through original research and literature reviews.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1993 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book IEEE Standard Specification Format Guide and Test Procedure for Single axis Interferometric Fiber Optic Gyros written by and published by . This book was released on 1998 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Specification and test requirements for a single-axis interferometric fiber optic gyro (IFOG) for use as a sensor in attitude control systems, angular rate measuring systems are defined. A standard specification format guide for the preparation of a single-axis IFOG is provided. A compilation of recommended procedures for testing a fiber optic gyro, derived from those presently used in the industry, is also provided.
Download or read book Long Distance High Bit Rate Systems written by IGIC, Inc. Staff and published by Information Gatekeepers Inc. This book was released on 1994 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 1248 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Compact Stellar X ray Sources written by Walter Lewin and published by Cambridge University Press. This book was released on 2006-04-06 with total page 667 pages. Available in PDF, EPUB and Kindle. Book excerpt: X-ray astronomy is the prime available window on astrophysical compact objects: black holes, neutron stars and white dwarfs. In this book, prominent experts provide a comprehensive overview of the observations and astrophysics of these objects. This is a valuable reference for graduate students and active researchers.
Download or read book Explanatory Supplement to the Astronomical Almanac written by United States Naval Observatory. Nautical Almanac Office and published by University Science Books. This book was released on 1992 with total page 786 pages. Available in PDF, EPUB and Kindle. Book excerpt: This well-schooled text provides a detailed description of how to perform practical astronomy or spherical astronomy. It is an authoritative source on astronomical phenomena and calendars.
