Download or read book Ocular Damage Thresholds for Repetitive Pulsed Argon Laser Exposure written by William D. Gibbons and published by . This book was released on 1974 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: The maculae of rhesus monkeys were exposed to radiation from an argon-ion laser operated at a wavelength of 514.5 nm in the TEMoo mode. Damage thresholds were determined for exposure to a single 40 microsec pulse and for different pulse train lengths and repetition rates of 40 microsec wide repetitive pulses. The single pulse threshold was determined to be 2.0 micro J. Thresholds for repetition rates of 100 and 1000 Hz at a pulse train length of 0.5 sec were both found to be 1.0 micro J per pulse. Exposures made at a repetition rate of 100 Hz for pulse train durations of 0.1 and 1.0 sec yielded thresholds of 2.0 and 0.4 micro J per pulse. These data indicate that pulse train length has a greater effect on threshold than repetition rate for the range of parameters studied. (Author).
Download or read book Ocular Hazards of Picosecond and Repetitive Pulsed Lasers Volume II Argon Ion Laser 514 5 Nm written by J. S. Connolly and published by . This book was released on 1978 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Retinal damage thresholds were determined for exposures of the maculae of rhesus monkeys to CW and repetitive-pulse trains of argon-ion laser radiation at 514.5 nm in the TEMoo mode. Single-pulse exposures were made at pulsewidths of 2, 10, 40, and 100 microsec and 1, 10, 100, and 500 msec. Repetitive-pulse exposures were made for 27 different combinations: train durations of 0.05, 0.5, 5, and 30 sec; pulse repetition frequencies from 0.10 Hz to 10 kHz and pulsewidths of 10, 40, and 100 microsec and 1 msec. Damage thresholds for mode-locked argon laser pulses at 104 MHz and 250 psec pulsewidth for pulse trains of 9.9-sec, 10-msec, and 10-microsec duration were also measured. For pulsewidths of 10 microsec, there is an apparent cumulative effect provided the repetition frequencies are in the range of approximately 0.1 to approximately 10 Hz. The retina is more sensitive to double-pulse exposures, by a factor of 2 to 3 relative to single-pulse thresholds, when the interpulse spacing is approximately 2.5 sec. Nonthermal damage mechanisms, involving a two-step, two-threshold process, may explain our results. Specifically, for double-pulse configurations, the first acts as a reversible photo-trigger which sensitizes the retina in preparation for the subsequent pulse. The elements of an empirical model have been assembled and appear to account satisfactorily for the observed double-pulse threshold data. (Author).
Download or read book Ocular Hazards of Picosecond and Repetitive Pulsed Lasers Volume I Nd YAG Laser 1064 Nm written by H. W Hemstreet (Jr) and published by . This book was released on 1978 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: Retinal damage thresholds are discussed for exposure of rhesus maculae to continuous wave and repetitive-pulse trains of 1064-nm Nd:YAG laser radiation. For all single-pulse exposures and for repetitive pulses contained within a 0.05-sec train, retinal damage appears to be induced primarily by thermal mechanisms. For the longer pulse-train durations, a cumulative effect is apparent when the repetition frequencies are in the range of>1 to
Download or read book High Resolution Imaging in Microscopy and Ophthalmology written by Josef F. Bille and published by Springer. This book was released on 2019-08-13 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book provides a comprehensive overview of the application of the newest laser and microscope/ophthalmoscope technology in the field of high resolution imaging in microscopy and ophthalmology. Starting by describing High-Resolution 3D Light Microscopy with STED and RESOLFT, the book goes on to cover retinal and anterior segment imaging and image-guided treatment and also discusses the development of adaptive optics in vision science and ophthalmology. Using an interdisciplinary approach, the reader will learn about the latest developments and most up to date technology in the field and how these translate to a medical setting. High Resolution Imaging in Microscopy and Ophthalmology – New Frontiers in Biomedical Optics has been written by leading experts in the field and offers insights on engineering, biology, and medicine, thus being a valuable addition for scientists, engineers, and clinicians with technical and medical interest who would like to understand the equipment, the applications and the medical/biological background. Lastly, this book is dedicated to the memory of Dr. Gerhard Zinser, co-founder of Heidelberg Engineering GmbH, a scientist, a husband, a brother, a colleague, and a friend.
Download or read book Safety with Lasers and Other Optical Sources written by D. H. Sliney and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 1042 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nearly a decade aga a general review article on the evaluation of optical radia tion hazards was published in Applied Optics (Sliney and Freasier, 1973). This arti cle received many favorable comments but also prompted many inquiries regarding specific optical hazard problems. From this it became evident that a monograph rather than a supplemental and expanded article was needed to fill this literature gap relating to laser and optical radiation hazards. The present work is designed to fill that gap, and is structured to permit either classroom or self-study use. Much of the material in this book was developed in eonnection with short courses on laser safety and radiometry in which we have participated, as weIl as from our previous articles. In particular, the sequenee of chapters is based upon the experiences which we have had in lecturing in courses with different schedules. One of the great difficulties in developing a text of this nature is that a broad, multidisciplinary background must be included in order that the reader can comprehend all of the subjeet matter readily. For this reason, the material presented on anatomy and physiology is orien ted toward the engineer or physical scientist, while the review material on basic optical physics is intended more for the physician or life scientist.
Download or read book Mechanisms of Retinal Damage from Chronic Laser Radiation Thresholds and Mechanisms written by Theodore Lawwill and published by . This book was released on 1977 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect upon the retina of exposure to large fields of bright visible light has been evaluated. The thresholds for permanent retinal damage for four hour exposures in rhesus monkeys have been established for white light, and laser lines of 514.5 nm, 488 nm, 457.9 nm, and 590 nm. The damage has been evaluated by ophthalmoscopy, electroretinography and light and electron microscopy. The shortest wavelength light (457.9 nm) is more effective in causing damage, particularly histological damage, which is spread throughout the fundus and throughout the retina layers. Functional damage shown by the electroretinogram follows a different action spectrum without the increased effect in the blue. There appears to be more than one mechanism for retinal damage in chronic light exposure, and at least one mechanism is not dependent solely upon the visual pigment and the pigment epithelium. Thresholds of permanent damage appear to be within one or two log units of light levels encountered in the normal visual environment. Newer data suggest that this damage is additive. Daily one hour exposures for four days produce damage equivalent to a single four hour exposure at the same retinal irradiance. (Author).
Download or read book Threshold Damage Evaluation of Long term Exposures to Argon Laser Radiation written by School of Aerospace Medicine and published by . This book was released on 1974 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The maculae of rhesus monkeys were exposed to an argon-ion laser operated in the TEMoo continuous wave (CW) mode at a wavelength of 514.5 nm. Damage thresholds (ED50) were determined for exposure times of 0.5, 5, 30, and 120 sec. Retinal damage was assessed at both 1-hr and 24-hr postexposure. With increasing exposure times, a 24-hr threshold criterion resulted in significantly lower threshold values, compared to a 1-hr criterion. Threshold values of 0.5 sec using 1-hr and 24-hr evaluation criteria were determined to be 9.4 and 9.0 mW, respectively; for 5 sec, 6.4 and 5.6 mW; for 30 sec, 5.4 and 2.5 mW; and for 120 sec, 4.4 and 0.54 nW. (Author).
Download or read book Research on Ocular Laser Thresholds written by Arthur Vassiliadis and published by . This book was released on 1969 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of experimental investigations of threshold levels for small retinal lesions are presented. Data for rhesus monkeys include thresholds for a Q-switched neodymium laser, both in the macula and in the paramacular area. In addition, extensive data are presented for argon, helium-neon, and neodymium-YAG laser damage threshold. Exposures of human volunteers to various lasers are reported. The lasers used were Q-switched neodymium and ruby lasers, a long-pulse ruby laser, and an argon laser. A report on the histopathology of retinal injury in rhesus monkeys due to Q-switched neodymium and argon lasers is included. (Author).
Download or read book Laser Safety written by Ken Barat and published by CRC Press. This book was released on 2017-12-19 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: New chapters and updates highlight the second edition of Laser Safety: Tools and Training. This text provides background information relating to lasers and laser safety, and examines the components of laser work and laser safety from a different perspective. Written by a working laser safety officer, the book considers ways to keep users, as well as those around them, safe. The author encourages readers to think beyond protective eyewear. As it relates to safety, he determines that if eyewear is required, then the laser system is not ideal. This book factors in optics, the vibration elements of the optical table, the power meter, and user training, elements that are not commonly considered in the context of laser safety. It presents ways for users to evaluate the hazards of any laser procedure and ensure that they are following documented laser safety standards. The material serves as a fundamental means or road map for laser users seeking to utilize the safest system possible. What’s New in the Second Edition: The second edition provides an inclusion of the Z136.8 Research Laser Standard, and offers updates and an explanation of eye exposure limits (MPE), presents new cases studies, and presents practical example images. It includes coverage of, laser lab design lessons, addresses user facility challenges and laser disposal. Presents case studies of real accidents, preventive measures, and templates for documenting potential laser risks and attendant safety measures Reviews factors often overlooked when one is setting up a laser lab Demonstrates how to investigate a laser incident This text which includes fundamental laser and laser safety information, as well as critical laser use information, is appropriate for both the novice and the seasoned professional.
Download or read book Study of Ocular Effects of Chronic Exposure to Laser Radiation written by T. Lawwill and published by . This book was released on 1973 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: The project is a study of the effects of long term exposure of the eye to laser radiation. The data is for four hour, wide field exposures at levels below immediate damage threshold for rabbit and monkey eyes. The report compares the thresholds for white light and the 514.5 and 488.0 nm lines of the argon laser. From this information a hypothesis is proposed as to the mechanism of damage and methods are proposed to test this hypothesis. If the mechanism can be established, generalizations can be made for different conditions and different light sources.
Download or read book Journal of Current Laser Abstracts written by and published by . This book was released on 1976 with total page 852 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of Laser and Noncoherent Ocular Effects written by Society of Photo-optical Instrumentation Engineers and published by SPIE-International Society for Optical Engineering. This book was released on 1997 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selected Papers on Laser Safety written by David H. Sliney and published by SPIE-International Society for Optical Engineering. This book was released on 1995 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt: SPIE Milestones are collections of seminal papers from the world literature covering important discoveries and developments in optics and photonics.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1984 with total page 1278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laser Based Optical Detection of Explosives written by Paul M. Pellegrino and published by CRC Press. This book was released on 2018-09-03 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser-Based Optical Detection of Explosives offers a comprehensive review of past, present, and emerging laser-based methods for the detection of a variety of explosives. This book: Considers laser propagation safety and explains standard test material preparation for standoff optical-based detection system evaluation Explores explosives detection using deep ultraviolet native fluorescence, Raman spectroscopy, laser-induced breakdown spectroscopy, reflectometry, and hyperspectral imaging Examines photodissociation followed by laser-induced fluorescence, photothermal methods, cavity-enhanced absorption spectrometry, and short-pulse laser-based techniques Describes the detection and recognition of explosives using terahertz-frequency spectroscopic techniques Each chapter is authored by a leading expert on the respective technology, and is structured to supply historical perspective, address current advantages and challenges, and discuss novel research and applications. Readers are left with an in-depth understanding and appreciation of each technology’s capabilities and potential for standoff hazard detection.
Download or read book Laser and Noncoherent Light Ocular Effects written by and published by . This book was released on 2003 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AGARD Conference Proceedings written by North Atlantic Treaty Organization. Advisory Group for Aerospace Research and Development and published by . This book was released on 1990 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt:
