An opticalmedium is material through which electromagnetic wave s propagate. It is a form of transmission medium . The permittivity and Permeability electromagnetism permeability of the medium define how electromagnetic waves propagate in it. The medium has an intrinsic impedance , given by math eta E x over H y math where math E x math and math H y math are the electric field and magnetic field , respectively. In a region with no electrical conductivity , the expression simplifies to math eta sqrt mu over varepsilon . math For example, in free space the intrinsic impedance is called the characteristic impedance of vacuum , denoted Z sub 0 sub , and math Z 0 sqrt mu 0 over varepsilon 0 . math Waves propagate through a medium with velocity math c w nu lambda math , where math nu math is the frequency and math lambda math is the wavelength of the electromagnetic waves. This equation also may be put in the form math c w omega over k , math where math omega math is the angular frequency of the wave and math k math is the wavenumber of the wave. In electrical engineering , the symbol math beta math , called the phase constant , is often used instead of math k math . The propagation velocity of electromagnetic waves in free space , an idealized standard reference state like absolute zero for temperature , is conventionally denoted by c sub 0 sub ref With ISO 31 5 , NIST and the BIPM have adopted the notation c sub 0 sub . ref math c 0 1 over sqrt varepsilon 0 mu 0 , math where math varepsilon 0 math is the electric constant and math mu 0 math is the magnetic constant . For a general introduction, see Serway ref name Serway cite book author Raymond Serway & Jewett J title Physics for scientists and engineers edition 6th Edition year 2003 publisher Thomson Brooks Cole location Belmont CA isbn 0 534 40842 7 url http worldcat.org isbn 0 534 40842 7 ref For a discussion of man made ... fiber Category Optics Medium Category Electric and magnetic fields in matter Medium cs Optick prost ed ... more details
wiktionary mediumMedium may refer to TOC right Communication Medium communication , storage and or transmission tools used to store and deliver information or data Transmission medium , in physics and telecommunications, any material substance which can propagate waves or energy Opticalmedium , material through which electromagnetic waves propagate Medium of instruction , any language or other tools used to educate, train, or instruct Natural science Processing medium , in industrial engineering, a material that plays a role in manufacturing processes Excitable medium , a nonlinear dynamic system which has the capacity to propagate a wave Gain medium , a quantum system that allows amplification of power gain of waves passing through usually by stimulated emission Growth medium or culture medium , in biotechnology, an object in which microorganisms or cells experience growth Interplanetary medium , in astronomy, material which fills the solar system Interstellar medium , in astronomy, the matter and energy content that exists between the stars within a galaxy Porous medium , in engineering ... Artistic medium The Medium , an opera by Gian Carlo Menotti The Medium 1951 film The Medium 1951 film , a film version of the opera directed by Menotti The Medium 1992 film The Medium 1992 film , an English film from Singapore Medium TV series Medium TV series , a television series about a research medium for a district attorney s office Other Medium spirituality , a practice in which a person claims to be an intermediary between the physical world and the spiritual world Medium Productions , a record label The Medium Rutgers The Medium Rutgers , an entertainment weekly at Rutgers Medium company See also Media disambiguation disambiguation af Medium cs Medium da Medium de Medium Begriffskl rung es Medium fr M dium it Medium disambigua he mk ms Medium nl Medium ja no Medium pl Medium simple Medium sk M dium fi Medium sv Medium zh ... more details
about the opera Medium disambiguation Menotti operas The Medium is a short one hour long two act dramatic opera with words and music by Gian Carlo Menotti . Commissioned by Columbia University , its first performance was there on 8 May 1946. The opera s first professional production was presented on a double bill with Menotti s The Telephone, or L Amour trois The Telephone at the Heckscher Theater, New York City, February 18 20, 1947 by the Ballet Society . The Broadway theatre Broadway production took place on May 1, 1947, at the Ethel Barrymore Theater with the same cast. ref http www.ibdb.com production.asp?ID 1549 Internet Broadway Database The Telephone The Medium Production Credits Bot generated title ref In 1951, Menotti directed, with the help of filmmaker Alexandr Hackenschmied Alexander Hammid , a The Medium 1951 film film version made to resemble film noir , and starring Anna Maria Alberghetti . A live television production starring Marie Powers took place on 12 December 1948 on the TV series Studio One TV series Studio One . Deleted image removed Image Vlcsnap 98649.png 300px Monica Anna Maria Alberghetti and Toby Leopoldo Savona Leo Coleman look for Mme. Flora in the village streets in the 1951 film version of The Medium , directed by the composer. right thumb Roles class wikitable Role Voice type Professional Premiere Cast, February 18, 1947 br Conductor Jascha Zayde Monica soprano Evelyn Keller actress Evelyn Keller Toby muteness mute Leo Coleman Madame Flora Baba contralto Marie Powers Mrs Gobineau soprano Beverly Dame Mr Gobineau baritone Frank Rogier Mrs ... Synopsis Act 1 The medium s parlor Monica, Madame Flora s daughter, and Toby, a mute servant boy ... The Medium 1951 at IMDB http www.imdb.com title tt0712518 The Medium 1948 at IMDB http www.imdb.com title tt0451121 The Medium 1977 at IMDB DEFAULTSORT Medium, The Category Operas by Gian Carlo Menotti ... Operas set in the United States de Das Medium es La m dium it The Medium simple The Medium ... more details
Infobox musical artist For groups see Wikipedia WikiProject Musicians name MediumMedium image 593203mm14.jpg alt MediumMedium in 2004 caption MediumMedium in 2004 image size landscape yes background group or band alias origin Nottingham , England genre Dance punk br Post punk br Funk years active Start date 1978 &ndash 1983, 2004&ndash label Cherry Red Records associated acts C Cat Trance website http www.mediummedium.com current members John Rees Lewis br Alan Turton br Andy Ryder br Steve Harvey past members Nigel Stone br Graham Spink br Leslie Joachim Barrett br Julie Wood MediumMedium were a post punk band from Nottingham , England, initially active between 1978 and 1983. History Emerging in 1978 out of Nottingham Punk rock punk rhythm & blues band The Press, ref name Unterberger Unterberger, Richie Allmusic class artist id p19279 pure url yes MediumMedium Biography , Allmusic , retrieved 2010 10 02 ref MediumMedium s debut single was Them or Me , which was released in late 1978 and was still selling well enough in 1980 to place in the UK Independent Chart . ref name Strong Strong, Martin C. 2003 The Great Indie Discography , Canongate, ISBN 1 84195 335 0, p. 257 ref ref name Lazell Lazell, Barry 1998 Indie Hits 1980 1989 , Cherry Red Books, ISBN 0 9517206 9 4, p. 145 ref The second single, Hungry, So Angry, was released in February 1981 on Cherry Red Records . One of the first records to introduce slap bass a technique borrowed from black funk music to a generally white audience, Hungry, So Angry reached the 48 spot in Billboard magazine Billboard s Disco chart and has ... a new record deal and MediumMedium split up in late 1983. Inspired by a Cherry Red retrospective CD release in 2001 and the subsequent dance punk revival, MediumMedium reformed in late 2004 for several ... venture, the band has stated plans to continue to write, record and perform. In 2010 MediumMedium released ... MySpace mediummedium MediumMedium Video http punkcast.com 593 PUNKCAST 593 live Knitting Factory NYC ... more details
Unreferenced date December 2009 The path that light takes in traversing an optical system is often called the optical path . The physical length of an optical device can be reduced to less than the length of the optical path by using folded optics . The optical path length as defined in optics is the length of the path multiplied by the index of refraction of the medium. See also Optical path length DEFAULTSORT Optical path Category Optics Optics stub de Strahlengang it Cammino ottico sv Str lg ng ... more details
media. The term transmission medium also refers to a technical device that employs the material substance to transmit or guide waves. Thus, an optical fiber or a copper cable is a transmission medium. Not only this but also is able to guide the transmission of networks. A transmission medium can be classified as a Linear medium , if different waves at any particular point in the medium can be superposition principle superposed Bounded medium , if it is finite in extent, otherwise unbounded medium Uniform medium or homogeneous medium , if its physical properties are unchanged at different points Isotropic medium , if its physical properties are the same in different directions. Image RG 59.jpg thumb right Coaxial cable , one example of a transmission medium Electromagnetic radiation can be transmitted through an opticalmediumoptical media , such as optical fiber , or through twisted ...dablink This article is about transmission of electrical, optical, or acoustic signals. For biological ... date July 2008 A transmission medium plural transmission media is a material substance solid , liquid ..., the transmission medium for sound received by the ears is usually air, but solids and liquids may also act as transmission media for sound. The absence of a material medium in vacuum may also constitute a transmission medium for electromagnetic wave s such as light and radio wave s. While material ... is, by definition, the vibration of matter, so it requires a physical medium for transmission ... aether theories to explain the transmission medium. However, it is now known that electromagnetic waves do not require a physical transmission medium, and so can travel through the vacuum of free space ... Guided or bounded waves are guided along a solid medium such as a transmission line . Wireless or unguided ... path examples of guided media include phone lines, twisted pair cables, coaxial cable s, and optical .... In the latter case, the medium is carrying signals in both directions at same time. See also ... more details
In digital storage, a Medium Error is a class of errors that a storage device can experience, which imply that a physical problem was encountered when trying to access the device. The word medium refers to the physical storage layer, the medium on which the data is stored as opposed to errors related to e.g. protocol, device controller driver state, etc. Medium errors are most commonly detected by checking the read data against a checksum itself being most commonly also stored on the same device. The mismatch of data to its supposed checksum is assumed to be caused by the data being corrupted. Locations of medium errors can be either temporary as in the case of bit rot there is no damage to the medium, the data was simply lost , or permanent as in the case of scratching the physical location is unusable from that point onwards . Devices can sometimes recover from medium errors, either by retrying or by managing to reconcile the data with the checksum. If the medium has incurred permanent damage, the device might remap the logical address where the error occurred to a different, undamaged physical location. Medium errors are often associated with long latency for the IOs. This is due to the device retrying and attempting to recover from the error. Examples of conditions that might cause medium errors The head executed a Read request while being improperly aligned, causing it to read data from a wrong physical position. Previous operation of the disk harmed the medium in some manner e.g. scratched it , corrupting data in the location that is now discovered as problematic. External conditions e.g. dust particles physically harmed the medium, or caused the head to harm the medium. A previous Write on a nearby physical location caused the head to corrupt bits in the read location imprecision in the physical write location . This is less likely in media that is mostly read only, such as optical media, unless the writing device is defective. Bit rot, i.e. the gradual, natural ... more details
Optical relief usually noted as simply relief is a concept in optical mineralogy which refers to the degree in which mineral grains stand out from the mounting medium, ref Nesse, W. D., 1991, Introduction of Optical Mineralogy, 2nd edition, p. 25. ref usually either oil with a known refractive index or Canada Balsam . Relief is an important part of the Becke line test . Magnitude Minerals that stand out significantly have a difference in refractive index of .12 or more have high or strong relief, and will have very sharp boundaries between itself and the material it is next to. Intermediate is .04 to .12, and low or weak is less than .04. Low relief materials have boundaries that are hard to distinguish from each other. Polarity Positive relief refers to a mineral that stands out higher than the medium, and negative relief is a mineral that appears to sink in . References reflist Nesse, W. D., 1991, Introduction of Optical Mineralogy, 2nd edition. Category Optical mineralogy petrology stub ... more details
Refimprove date May 2007 Optical communication is any form of telecommunication that uses light as the transmission medium . An optical communication system consists of a transmitter , which encodes a message into an optical signal information theory signal , a channel communications channel , which ... optical signal. Forms of optical communication File Bundesarchiv Bild 102 09520, Kieler Hafen, Abfahrt der Deutschen Hochseeflotte.jpg thumb Naval signal There are many forms of non technological optical ... s, ship flags , smoke signals , and beacon beacon fires were the earliest form of technological optical ... an Aldis lamp to communicate with planes whose radio failed. Free space optical communication is also used today in a variety of applications. Optical fiber communication Main article Fiber optic communication . Optical fiber is the most common type of channel for optical communications, however, other types of optical waveguide s are used Light Peak within computers or communications gear, and have ... trials. The transmitters in optical fiber links are generally light emitting diode s LEDs or laser diode s. Infrared light, rather than visible light is used more commonly, because optical fibers transmit ... optical phase and frequency modulation have been demonstrated in the lab. The need for periodic ... , which extended link distances at significantly lower cost. Free space optical communication Main article Free space optical communication . Free Space Optics FSO systems are generally employed for last ... Line of sight propagation line of sight between the source and the destination, and the optical ... of low data rate, short distance free space optical communications using LEDs. Other free space ... subsystems. ref cite web last Wilson first K. title Recent Development in High Data Rate Optical Communications ... Technical Reports Server accessdate 4 October 2011 ref See also Commons category Optical communication Laser Optical telegraph Heliograph Photophone Telegraph Jun Ichi Nishizawa an inventor of optical ... more details
Refimprove date December 2009 Optical storage is a term from engineering referring to the storage of data on an optically readable medium. Data is recorded by making marks in a pattern that can be read back with the aid of light , usually a beam of laser light precisely focused on a spinning disc. An older example, that does not require the use of computers, is microform . There are other means of optically storing data and new methods are in development. Optical storage differs from other computer data storage data storage techniques that make use of other technologies such as magnetism or semiconductor s. Optical storage can range from a single drive reading a single CD ROM to multiple drives reading multiple discs such as an optical jukebox . Single compact discs can hold around 700MB megabyte s and optical jukebox es can hold much more ref Compact Disc http en.wikipedia.org wiki Compact Disc ref . The term optical drive usually refers to a device in a computer that can read CD ROM s or other optical disc s. It is estimated that in the year 2007, optical storage represents 27 of the world s technological capacity to store information ref name HilbertLopez2011 http www.sciencemag.org content 332 6025 60 The World s Technological Capacity to Store, Communicate, and Compute Information , especially http www.sciencemag.org content suppl 2011 02 08 science.1200970.DC1 Hilbert SOM.pdf ... also Data storage device the broader topic of all devices that store data. Optical Media board disc modern optical discs such as CD ROM s and related formats. Optical Jukebox Optical disc drive Optical tape more capacity than magnetic tape but not as cost effective Magneto optical drive combines Optical ... data storage media. HDSS Holographic Data Storage Systems potential new optical storage technology. 3D optical data storage potential new optical storage technology. Optical Storage Technology Association industry trade association References Reflist Optical storage media DEFAULTSORT Optical Storage ... more details
energy emitted. Note that the optical depth of a given medium will be different for different colors wavelength s of light. For planetary rings , the optical depth is the proportion of light blocked ...Other uses Optical depth astrophysics Optical depth , or optical thickness , is a measure of transparency optics transparency . Optical depth is defined by the negative natural logarithm of the fraction of radiation e.g., light that is not scattered or absorbed on a path. Hence optical depth is Dimensionless quantity dimensionless , and particularly is not expressed in units of length however the optical .... Formulations The optical depth expresses the quantity of light removed from a beam by scattering or absorption electromagnetic radiation absorption during its path through a transmission mediummedium ... is the observed intensity after a given path, then optical depth math tau math is defined by the following ... Stars, Nebulae and the Interstellar Medium Observational Physics and Astrophysics publisher CRC Press ... , the optical depth of a cloud of atoms can be calculated from the quantum mechanical properties of the atoms ... , one often refers to the optical depth of the atmosphere as corresponding to the vertical path from Earth s surface to outer space at other times the optical path is from the observer s altitude to outer space. Since &tau refers to a vertical path, the optical depth for a slant path is &tau &prime ... system zenith angle corresponding to the given path. Therefore math I I 0 e m tau . , math The optical ... , particulate aerosols , and gaseous absorption electromagnetic radiation absorption . The optical ... where its optical depth is 2 3. This means that each photon emitted at the photosphere suffers an average of less than one scattering before it reaches the observer. At the temperature at optical depth ... http scienceworld.wolfram.com physics OpticalDepth.html optical depth equations Category Scattering ... Optical depth sk Optick hr bka sl Opti na globina zh ... more details
copy edit date April 2012 nr date March 2010 About the optical component the optoelectronic component Slotted optical switch In telecommunication , an optical switch is a switch that enables signals in optical fiber s or integrated optical circuit s IOCs to be selectively switched from one Telecommunication ... such as the telecom optical switch market size it refers to any piece of circuit switching equipment ... the world of telecom systems, an optical switch is the unit that actually switches light between ... light i.e., to switch wavelengths or signals within a given fiber . Hence a certain portion of the optical switch market is made up of photonic switches. These will contain within them an optical switch, which will, in a small number of cases, be a photonic switch. Operation An optical switch may operate by mechanical means, such as physically shifting an optical fiber to drive one or more alternative fibers, or by electro optic effect s, magneto optic effect s, or other methods. Slow optical switches, such as those using moving fibers, may be used for alternate routing of an optical switch ... . Fast optical switches, such as those using electro optic or magneto optic effects, may be used to perform logic operation s also included in this category are the semiconductor optical amplifiers , which are optoelectronic devices that can be used as optical switches and be integrated with discrete or integrated microelectronic circuits. Patents A search on optical switch http patft.uspto.gov ... involving arrays of micromirrors that can deflect an optical signal to the appropriate receiver ... enhanced optical switching characteristics Inkjet methods involving the intersection of two waveguides ... Nonlinear methods e.g., Patent 5,319,492 that vary the diffraction pattern in a medium by taking ... it is e.g., Patent 7,027,211 . See also Optical cross connect Optical buffer Optical transistor Optical ... Chip ABC TV Science References FS1037C Category Fiber optic communications Switch, optical optics ... more details
tape or optical discs. For example, the goal of the LOTS project in 1995 was to achieve a data transfer ... contact with a magnetic head. See also Creo Former manufacturer of Optical tape recorders, now a part of Kodak . TRAAMS Tape based Rapid Access Affordable Mass Storage An optical tape technology developed by a consortium led by Terabank , Inc.. LOTS Laser Optical Tape Storage Another optical ... 2001 EmergTechPanel LOTS 20Conf2001.pdf Technical explanation of Laser Optical Tape Storage technology LOTS . ref References Reflist Optical storage media DEFAULTSORT Optical Tape Category Optical computer storage media de Optisches Band ... more details
Refimprove date December 2009 An optical microcavity is a structure formed by reflecting faces on the two sides of a spacer layer or opticalmedium. The name micro cavity stems from the fact that it is often only a few micrometers thick, the spacer layer sometimes even in the nanometer range. As with common laser s this forms an optical cavity or optical resonator , allowing a standing wave to form inside the spacer layer. The thickness of the spacer layer determines the so called cavity mode , which is the one wavelength that can be transmitted and will be formed as standing wave inside the resonator. Depending on the type and quality of the mirrors, a so called stop band will form in the transmission spectrum of the microcavity, a long range of wavelength s, that is reflected and a single one being transmitted. usually in the centre The fundamental difference between a conventional optical cavity and microcavities is the effects that arise from the small dimensions of the system. Quantum effects of the light s electromagnetic field can be observed. For example, the spontaneous emission rate and behaviour of atom s is altered by such a microcavity. One can imagine this as the situation that no photon is emitted, if the environment is a box that is too small to hold it. This leads to an altered emission spectrum , which is significantly narrowed. There are different means of fabricating microcavities, either by evaporating alternating layers of dielectric media to form the mirrors Distributed Bragg reflector DBR and the medium inside the spacer layer or by modification of semiconductor material or by metal mirrors. Microcavities have many applications preferably in optoelectronics ... pages 839 846 last Vahala first Kerry J. title Optical microcavities journal Nature year 2003 unused data DUPLICATE DATA doi 10.1038 nature01939 ref References reflist DEFAULTSORT Optical Microcavity Category Optical devices Category Laser science ... more details
of the nonlinear opticalmedium. A popular material for generating radiation in the 0.5&ndash 3 THz range 1 mm wavelength is zinc telluride . Optical rectification also occurs on metal ...Electro optic rectification EOR , also referred to as optical rectification , is a non linear optics non linear optical process which consists in the generation of a quasi DC Polarization electrostatics polarization in a non linear medium at the passage of an intense optical beam. For typical intensities, optical rectification is a second order phenomenon difference frequency mixing ref Rice et al. , Terahertz optical rectification from 110 zinc blende crystals, Appl. Phys. Lett. 64 , 1324 1994 ref which is based on the inverse process of the electro optic effect . It was reported for the first time in 1962, ref Bass et al. , Optical rectification, Phys. Rev. Lett. 9 , 446 1962 ref when radiation from a ruby laser was transmitted through potassium dihydrogen phosphate KDP and potassium dideuterium phosphate KD sub d sub P crystals. Explanation Optical rectification can be intuitively explained in terms of the symmetry properties of the non linear medium in the presence of a preferred internal direction, the polarization will not reverse its sign at the same time as the driving field. If the latter is represented by a sinusoidal wave, then an average DC polarization will be generated. This is the analogue of the Rectifier electric rectification effect , where an AC signal is converted rectified to DC. When the applied electric field is delivered by a femtosecond Pulsed laser Pulsed operation pulse width laser , the spectral bandwidth associated with such short pulses is very large. The mixing of different frequency components produces a beating polarization, which results in the emission ... Kadlec, F., Kuzel, P., Coutaz, J. L., Study of terahertz radiation generated by optical rectification ... in semiconductors and polymers, optical rectification is one of the main mechanisms for the generation ... more details
Medium , Carnegie Observatories Centennial Symposia, p.422, 2004. ref Observing As the ICM ... of cooling of the ICM. See also Galaxy cluster Intergalactic medium Interstellar medium List of plasma physics articles References Reflist DEFAULTSORT Intracluster Medium Category Galaxy clusters ... Medium fr Milieu intra amas ja zh ... more details
Physical medium may refer to For a medium used in the propagation of energy waves, see Transmission medium For the practice of physical mediumship and the conducting of seance , see Mediumship Physical mediumship Physical mediumship disambig ... more details
wiktionary medium rare Medium Rare may refer to Medium rare , a degree of doneness used with cooking meat Medium Rare film Medium Rare film , a 1992 film from Singapore Medium Rare radio show Medium Rare radio show 1987 1993 , a radio program on CHEZ FM from Ottawa, Canada Medium Rare Foo Fighters album Medium Rare Foo Fighters album , a 2011 alternative rock album by Foo Fighters Medium Rare The Mighty Mighty Bosstones album Medium Rare The Mighty Mighty Bosstones album , a 2007 ska punk compilation album by The Mighty Mighty Bosstones disambig nl Medium Rare ... more details
Unreferenced date November 2010 In telecommunications , an optical buffer is a device that is capable of temporarily storing light. Just as in the case of a regular buffer telecommunication buffer , it is a storage medium that enables compensation for a difference in time of occurrence of events. More specifically, an optical buffer serves to store data that was transmitted optically i.e., in the form of light , without converting it to the electrical domain. Optical networks Today, computer networks consist of optical fiber links, interconnected by electrical nodes. The data transport in the backbone is done in the form of light, typically from LED or laser . DWDM technologies enable bitrates well beyond 1 Tbit s. However, at the nodes, this light has to be converted to the electronic domain, in order to switch all data to their separate destinations. Due to rapidly increasing channel capacities, the switching capacity is becoming the bottleneck of the system. Currently, research activities focus on optical switching technologies, that involve fewer or no conversions from the optical to the electronic domain. An important problem however, is the buffering. Contention resolution Whenever two or more data packets arrive at a network node at the same time and contend for the same output, external blocking occurs. All packets but one are perceived as superfluous, and have to be dealt with. Next to the obvious choice of dropping all excess packets, academic literature typically presents three solutions buffering, deflection routing or wavelength conversion. Optical buffering uses ... cost of the FDLs. Implementation of optical buffers As light cannot be frozen, an optical buffer is made of optical fibers, and is generally much larger than a RAM chip of comparable capacity ... on optical buffers is performed in two separate fields. One is to investigate on the technological ... author s homepage . Category Fiber optic communications Buffer, optical ... more details
Orphan date February 2009 Optical decay is process of relaxation of excitation of an excited quantum system, usually due to the spontaneous emission of a photon or a phonon . Optical decay is dominant mechanism of quenching of excitation of active optical media. In solid state laser s the optical decay limits the storage of energy in active medium. Also, the term optical decay is used to the effect of quick reduction of luminosity of astrophysical objects ref name a http edoc.mpg.de 199219 doi 10.1051 0004 6361.20034409 ref Phenomenology of optical decay In the first approximation, the optical decay can be treated as just spontaneous emission , and its rate is determined with the Einstein Coefficients . For the most of laser systems, the effects of decoherence determine the spectral width of the emitted photons, and there is no reason to consider in detail the evolution of isolated quantum mechanical systems which show the optical decay. Shape of specral line at the optical decay of an idealized atom The isolated quantum system atom, ion, molecule or even a quantum dot may have metastable states, weakly coupled to the outer world. Some couliknd should be taken into account otherwize, there is no optical decay. In the idealized case, the evolution of the system is disturbed only by the interaction with the continuum of the modes of the electromagnetic field. Then, the spectral width of the emitted photons is determined by the relaxation rate. For the narrow spectral lines, the decay is almost exponential then, the profile of the spectral line is determined by the Fourier transform of the exponential decay of the quantum amplitude of probability that the system is still excited this profile is Lorentian. ref name W V.Weisscopf, E.Wigner. Berechnung der naturlichen Lichtteorie ... Optical decay from a Fabry Perot cavity faster than the decay time. JOSA B , http heart c704.uibk.ac.at ..., K.Hakuta. title Optical nanofiber as an efficient tool for manipulating and probing atomic fluorescence ... more details
italic title taxobox name Trifolium medium image TrifoliumMedium.jpg regnum Plant ae unranked divisio Angiosperms unranked classis Eudicots unranked ordo Rosids ordo Fabales familia Fabaceae genus Trifolium species T. medium binomial Trifolium medium binomial authority Carolus Linnaeus L. commons Trifolium medium Trifolium medium or Zigzag Clover is a plant species of the genus Trifolium . quattrofolium http www.quattrofolium.com eng medium.html Category Trifolium medium Faboideae stub az Trifolium medium da Bugtet Kl ver de Mittlerer Klee es Trifolium medium et Keskmine ristik eu Trifolium medium hsb Mjezny d e el nl Bochtige klaver no Skogkl ver pl Koniczyna pogi ta fi Mets apila sv Skogskl ver vi Trifolium medium ... more details
Unreferenced stub auto yes date December 2009 In industrial engineering , a gaseous, vaporous, fluid or shapeless solid material that plays an active role in manufacturing processes comparable to that of a tool. Examples A processing medium for washing is a soap solution, a processing medium for steel melting is a plasma, and a processing medium for steam drying is superheated steam . Synonyms Operating medium Working medium. DEFAULTSORT Processing Medium Category Engineering concepts Mech engineering stub ... more details
In telecommunication , the term record medium has the following meanings The physical Recording mediummedium on which information is stored in recoverable form. For example, magnetic tape or disk. In Fax facsimile transmission telecommunications transmission , the physical medium on which the recorder forms an image of the object, i.e. , creates the recorded Copying copy . Most commonly, a sheet of paper . The record medium and the record sheet may be identical. Synonym record sheet . References FS1037C MS188 Category Telecommunications ... more details
For the power of light Radiant flux Luminous flux Optical power also referred to as dioptric power , refractive power , focusing power , or convergence power is the degree to which a lens optics lens , mirror , or other optical system converges or diverges light. It is equal to the Multiplicative inverse reciprocal of the focal length of the device. ref cite book first John E. last Greivenkamp year 2004 title Field Guide to Geometrical Optics publisher SPIE others SPIE Field Guides vol. FG01 isbn 0 8194 5294 7 page 7 ref The dioptre is the most common unit of measurement of optical power. The SI unit for optical power is the inverse metre m sup 1 sup . For two or more thin lens es close together, the optical power of the combined lenses is approximately equal to the sum of the optical powers of each lens. Similarly, the optical power of a single lens is roughly equal to the sum of the powers of each surface. These approximations are commonly used in optometry . When a lens is immersed in a medium optics refractive medium , its optical power and focal length change. A description of how they change, with reference to a reliable source, would be useful here. An human eye eye that has too much or too little refractive power to focus optics focus light onto the retina has a refractive error . A myopic eye has too much power so light is focused in front of the retina. Conversely, a hyperopic eye has too little power so when the eye is relaxed, light is focused behind the retina. An eye with a refractive power in one Meridian perimetry, visual field meridian that is different from the refractive power of the other meridians has Astigmatism eye astigmatism . Anisometropia is the condition in which one eye has a different refractive power than the other eye. See also Vergence optics Vergence Lens clock Vertometer Lensmeter Plate scale References references Category Optics Power optics stub cs Optick mohutnost es Potencia ptica id Daya optis kk mk ... more details
Orphan date February 2009 italictitle Taxobox name Athyrium medium image status LC status system IUCN3.1 regnum Plantae divisio Pteridophyta classis Pteridopsida ordo Polypodiales familia Athyriaceae genus Athyrium species A. medium binomial Athyrium medium binomial authority Carmich. T.Moore synonyms Athyrium medium is a species of fern in the Athyriaceae family. It is found in Tristan da Cunha . Its natural habitat is subantarctic shrubland . References Roux, J.P. 2003. http www.iucnredlist.org search details.php 43917 all Athyrium medium . http www.iucnredlist.org 2006 IUCN Red List of Threatened Species. Downloaded on 20 August 2007. Category Athyrium medium Category Fern species Category Least concern plants Category Flora of Tristan da Cunha SaintHelena stub fern stub vi Athyrium medium ... more details
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