Updated Sept 42017 To look for a nonbook abbreviation or glossary entry, go to the Search form and follow instructions. Common abbreviations DSS Dea Sea Scrolls. BibMe Free Bibliography Citation Maker MLA, APA, Chicago, Harvard. UT Austin How to Study Physics,. Le pouvoir de rsolution, ou pouvoir de sparation, ou pouvoir sparateur, ou la rsolution spatiale, exprime la capacit dun systme optique de mesure ou d. Eugene Hecht Physics Pdf Textbook' title='Eugene Hecht Physics Pdf Textbook' />Review Article. Current Concepts. Computed Tomography An Increasing Source of Radiation Exposure. David J. Brenner, Ph. D., D. Sc., and Eric J. Hall, D. Phil., D. Sc. An error occurred while setting your user cookie. Please set your. browser to accept cookies to continue. NEJM. org uses cookies to improve performance by remembering your. ID when you navigate from page to page. This cookie stores just a. ID no other information is captured. Accepting the NEJM cookie is. Optics Wikipedia. Optics is the branch of physics which involves the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviolet, and infrared light. Because light is an electromagnetic wave, other forms of electromagnetic radiation such as X rays, microwaves, and radio waves exhibit similar properties. Most optical phenomena can be accounted for using the classical electromagnetic description of light. Complete electromagnetic descriptions of light are, however, often difficult to apply in practice. Practical optics is usually done using simplified models. The most common of these, geometric optics, treats light as a collection of rays that travel in straight lines and bend when they pass through or reflect from surfaces. Physical optics is a more comprehensive model of light, which includes wave effects such as diffraction and interference that cannot be accounted for in geometric optics. Historically, the ray based model of light was developed first, followed by the wave model of light. Progress in electromagnetic theory in the 1. Some phenomena depend on the fact that light has both wave like and particle like properties. Explanation of these effects requires quantum mechanics. Free Download Nikon Ne 20S Owners Manual Programs For Low Income on this page. When considering lights particle like properties, the light is modelled as a collection of particles called photons. Quantum optics deals with the application of quantum mechanics to optical systems. Optical science is relevant to and studied in many related disciplines including astronomy, various engineering fields, photography, and medicine particularly ophthalmology and optometry. Practical applications of optics are found in a variety of technologies and everyday objects, including mirrors, lenses, telescopes, microscopes, lasers, and fibre optics. HistoryeditOptics began with the development of lenses by the ancient Egyptians and Mesopotamians. The earliest known lenses, made from polished crystal, often quartz, date from as early as 7. BC for Assyrian lenses such as the LayardNimrud lens. The ancient Romans and Greeks filled glass spheres with water to make lenses. These practical developments were followed by the development of theories of light and vision by ancient Greek and Indian philosophers, and the development of geometrical optics in the Greco Roman world. The word optics comes from the ancient Greek word optik, meaning appearance, look. Greek philosophy on optics broke down into two opposing theories on how vision worked, the intromission theory and the emission theory. The intro mission approach saw vision as coming from objects casting off copies of themselves called eidola that were captured by the eye. With many propagators including Democritus, Epicurus, Aristotle and their followers, this theory seems to have some contact with modern theories of what vision really is, but it remained only speculation lacking any experimental foundation. Plato first articulated the emission theory, the idea that visual perception is accomplished by rays emitted by the eyes. He also commented on the parity reversal of mirrors in Timaeus. Some hundred years later, Euclid wrote a treatise entitled Optics where he linked vision to geometry, creating geometrical optics. He based his work on Platos emission theory wherein he described the mathematical rules of perspective and described the effects of refraction qualitatively, although he questioned that a beam of light from the eye could instantaneously light up the stars every time someone blinked. Ptolemy, in his treatise Optics, held an extramission intromission theory of vision the rays or flux from the eye formed a cone, the vertex being within the eye, and the base defining the visual field. The rays were sensitive, and conveyed information back to the observers intellect about the distance and orientation of surfaces. He summarised much of Euclid and went on to describe a way to measure the angle of refraction, though he failed to notice the empirical relationship between it and the angle of incidence. Alhazen Ibn al Haytham, the father of Optics9During the Middle Ages, Greek ideas about optics were resurrected and extended by writers in the Muslim world. One of the earliest of these was Al Kindi c. Aristotelian and Euclidean ideas of optics, favouring the emission theory since it could better quantify optical phenomena. In 9. 84, the Persian mathematician Ibn Sahl wrote the treatise On burning mirrors and lenses, correctly describing a law of refraction equivalent to Snells law. He used this law to compute optimum shapes for lenses and curved mirrors. In the early 1. 1th century, Alhazen Ibn al Haytham wrote the Book of Optics Kitab al manazir in which he explored reflection and refraction and proposed a new system for explaining vision and light based on observation and experiment. He rejected the emission theory of Ptolemaic optics with its rays being emitted by the eye, and instead put forward the idea that light reflected in all directions in straight lines from all points of the objects being viewed and then entered the eye, although he was unable to correctly explain how the eye captured the rays. Alhazens work was largely ignored in the Arabic world but it was anonymously translated into Latin around 1. A. D. and further summarised and expanded on by the Polish monk Witelo1. Europe for the next 4. In the 1. 3th century in medieval Europe, English bishop Robert Grosseteste wrote on a wide range of scientific topics, and discussed light from four different perspectives an epistemology of light, a metaphysics or cosmogony of light, an etiology or physics of light, and a theology of light,2. Aristotle and Platonism. Grossetestes most famous disciple, Roger Bacon, wrote works citing a wide range of recently translated optical and philosophical works, including those of Alhazen, Aristotle, Avicenna, Averroes, Euclid, al Kindi, Ptolemy, Tideus, and Constantine the African. Bacon was able to use parts of glass spheres as magnifying glasses to demonstrate that light reflects from objects rather than being released from them. The first wearable eyeglasses were invented in Italy around 1. This was the start of the optical industry of grinding and polishing lenses for these spectacles, first in Venice and Florence in the thirteenth century,2. Netherlands and Germany. Spectacle makers created improved types of lenses for the correction of vision based more on empirical knowledge gained from observing the effects of the lenses rather than using the rudimentary optical theory of the day theory which for the most part could not even adequately explain how spectacles worked. This practical development, mastery, and experimentation with lenses led directly to the invention of the compound optical microscope around 1. Netherlands. 2. 62. In the early 1. 7th century Johannes Kepler expanded on geometric optics in his writings, covering lenses, reflection by flat and curved mirrors, the principles of pinhole cameras, inverse square law governing the intensity of light, and the optical explanations of astronomical phenomena such as lunar and solar eclipses and astronomical parallax. He was also able to correctly deduce the role of the retina as the actual organ that recorded images, finally being able to scientifically quantify the effects of different types of lenses that spectacle makers had been observing over the previous 3. After the invention of the telescope Kepler set out the theoretical basis on how they worked and described an improved version, known as the Keplerian telescope, using two convex lenses to produce higher magnification. Cover of the first edition of Newtons Opticks. Optical theory progressed in the mid 1.