Unreferenced stub auto yes date December 2009 An optical reader is a device found within most computer Image scanner scanners that captures visual information and translates the image into digital information the computer is capable of understanding and displaying. An example of optical readers are marksense systems for election s where voters mark their choice by filling a rectangle, circle or oval, or by completing an arrow. After the voting a tabulating device reads the votes using dark mark logic , whereby the computer selects the darkest mark within a given set as the correct choice or vote. Marksense is also used extensively in such areas as lottery lotteries and multiple choice tests. See also Digital paper Optical scan voting system References reflist noreferences date March 2010 DEFAULTSORT Optical Reader Optics stub Category Optical devices ... 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 circuit circuit to another. Terminology The word is used on several levels. In commercial terms 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 ... 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
Multiple issues unreferenced December 2009 orphan November 2006 context October 2009 Optical films are several kinds of industrial and chemical thin film optics . They are mainly used for liquid crystal display panels. DEFAULTSORT Optical Film Category Liquid crystal displays Video tech stub ... 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
TMB Optical of Cleveland, OH is a manufacturer of amateur optical telescope telescopes and accessories, specializing in apochromat ic refracting telescope refractors and astronomical eyepiece s. TMB was named after its founder, optics designer Thomas M. Back . Besides producing optical equipment, TMB has licensed optics designs to other manufacturers, such as Astronomics and Burgess Optical. Thomas M. Back died in September, 2007, but the company continues in operation. External links http www.tmboptical.com Company website http www.cloudynights.com item.php?item id 1549 An interview with Thomas Back Category Telescope manufacturers Category Companies based in Cleveland, Ohio US manufacturing company stub ... more details
Image Optical Trap Ray Optics Explanation.jpg thumb right A Free body diagram force diagram showing how vertical and lateral stabilization occurs in a vertically oriented optical trap. Optical levitation is a method developed by Arthur Ashkin whereby a material is levitation levitated against the downward force of gravity by an upward force stemming from photon momentum transfer. Typically photon radiation pressure of a vertical upwardly directed and focused laser beam of enough intensity counters the downward force of gravity to allow for a stable optical tweezers optical trap capable of holding small particles in suspension. Micrometer sized from several to 50 micrometer in diameter transparent dielectric spheres such as fused silica spheres, oil or water droplets, are used in this type of experiment. The laser radiation can be fixed in wavelength such as that of an argon ion laser or that of a tunable dye laser . Laser Power physics power required is of the order of 1 Watt focused to a spot size of several tens of micrometers. Phenomena related to morphology dependent resonance s in a spherical optical cavity have been studied by several research groups. For a shiny object, such as a metallic micro sphere, stable optical levitation has not been achieved. See also Electrostatic levitation Magnetic levitation Acoustic levitation Aerodynamic levitation Laser propulsion List of laser articles Physics stub Category Levitation ko ... more details
Unreferenced date November 2006 An optical turnstile is a physical security device designed to restrict or control access to a building or secure area . Optical turnstiles are usually a part of an access control system, which also consists of software, card readers, and controllers. Optical turnstiles operate much like regular mechanical turnstile s, except that they rely primarily on electronic infrared beams, and audible visual interfaces to control entry. Rather than physically restraining a person, the optical turnstile uses sounds and lights to alert others to attempted entry by unauthorized individuals. For this reason, the products are not likely to be used in Subway rail subway s and stadium s, so much as they are suited for settings where design and aesthetics are important, such as Lobby room lobbies . They are perfect for high rise buildings with a single path through the lobby and staffed reception. The rate of people passing through the optical turnstile checkpoint is high, lessening the delay that other methods would have. They are also suitable for the handicapped in that they are barrier free. Early optical turnstiles used programmable logic controllers and banks of relays to control the access card and infrared sensor inputs and the indicating lights and audible outputs. These older designs required a large control footprint and were very complicated. The first optical turnstiles were developed for the San Francisco market by Omega Corporate Security of Walnut Creek, California . Early installations included Charles Schwab Corp. Charles Schwab , East Bay Municipal Utility District , and Wells Fargo . See also multicol Access control ID Card multicol break Physical security Security multicol break Stile Turnstile multicol end External links http www.turnstile.com products optical Types of Optical Turnstiles by a US Manufacturer DEFAULTSORT Optical Turnstile Category Security Category Types of gates ... more details
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 depth to an object will typically approach zero as the spatial distance to the object decreases. 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 medium medium ... is the observed intensity after a given path, then optical depth math tau math is defined by the following ... , 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 ... 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 ... 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
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
Unreferenced date December 2009 Image Laser.jpg thumb 300px A laser system on an optical table. An optical table is platform that is used to support systems used for optics experiment s and Optical engineering engineering . Explanation In optical systems, especially those involving interferometry , the alignment .... The surface of the table must also be quite flat, to allow precision optical mounts to make good contact with the table without rocking and facilitate easy assembly of the optical system. Earlier optical table tops were sometimes made of a large slab of highly polished granite . The heavy, dense ... stable surface that improves the stability of the optical system. Such tables were very heavy and expensive, however, and are not commonly available today. Modern optical tables are typically made ... to be bolted down to fit the optical system layout. Components may also be held to the steel ... by special air conditioning . The metal used to construct modern optical tables has a higher speed ... M6 25 mm Imperial 20 Unified National Coarse UNC 1 25.4mm Breadboards An alternative to an optical table is an optical breadboard . Some optical systems use breadboards made of solid aluminum for later integration with a larger system with some form of vibration control. Most optical breadboards are constructed ... on an ordinary table or workbench. Breadboards are not as good as optical tables, but weigh less and are adequate for smaller optical systems that do not require extremely high levels of mechanical ... onto an optical table, build up a module of the experiment on it, and then transfer the module as a whole ..., custom built optical devices are assembled and aligned on breadboards, which are then enclosed in a case ... neon laser on an optical bench. An optical bench or optical rail is a less sophisticated piece of equipment ... Optical bench simulation https www.cvimellesgriot.com Products Documents TechnicalGuide Fundamentals Vibration Isolation.pdf Fundamentals of Vibration Isolation for Optical Tables DEFAULTSORT ... more details
books?id uqo9AAAAIAAJ&pg PA26&dq optical window&cd 15 v onepage&q optical 20window&f false format Hardcover. 170 pgs. isbn 978 0 85109 021 4 ref In medical physics , the optical window is the portion .... In optics, it means a usually at least Float glass mechanically flat , sometimes optical flat ..., not necessarily for visible light optical material that allows light into an optical instrument ... , at least if it is designed for visible light. An optical window may be built into a piece of equipment such as a vacuum chamber to allow optical instruments to view inside that equipment. See also Optical window in biological tissue Radio window References Reflist DEFAULTSORT Optical Window Category Optical spectrum id Jendela optik no Optisk vindu pl Okno optyczne sr sv Optiskt ... more details
unreferenced date December 2006 In optics , optical bistability is an attribute of certain optical device s where two resonant transmissions state s are possible and stable, dependent on the input. Optical devices with a feedback mechanism , e.g. a laser , provide two methods of achieving bistability . Absorptive bistability utilizes an absorber to block light inversely dependent on the intensity of the source light. The first bistable state resides at a given intensity where no absorber is used. The second state resides at the point where the light intensity overcomes the absorber s ability to block light. Refractive bistability utilizes an optical mechanism that changes its refractive index inversely dependent on the intensity of the source light. The first bistable state resides at a given intensity where no optical mechanism is used. The second state resides at the point where a certain light intensity causes the light to resonate to the corresponding refractive index. This effect is caused by two factors Nonlinear atom field interaction Feedback effect of mirror Important cases that might be regarded are Atomic detuning Cooperating factor Cavity mistuning Applications of this phenomenon include its use in optical transmitters, memory elements and pulse shapers. Category Optics engineering stub ... more details
Refimprove date August 2008 An optical pulsar is a pulsar which can be detected in the visible spectrum. There are very few of these known the Crab pulsar was detected by stroboscopic techniques in 1969, shortly after its discovery in radio waves, at the Steward Observatory . The Vela pulsar was detected in 1977 at the Anglo Australian Observatory , and was the faintest star ever imaged at that time. Six known optical pulsars are list by http adsabs.harvard.edu abs 2002nsps.conf...44S Shearer and Golden 2002 class wikitable Name of pulsar Absolute magnitude Magnitude br B Crab Pulsar CM Tauri 17 Vela Pulsar 24 PSR B0540 69 in the Large Magellanic Cloud 23 PSR B0656 14 26 PSR B0633 17 Geminga 25.5 PSR B1509 58 25.7 colspan 2 small Source included but not discussed in paper by source paper. small ref Proceedings of the 270. WE Heraeus Seminar on Neutron Stars, Pulsars, and Supernova Remnants. MPE Report 278. Why study pulsars optically? Shearer, A. & Golden, A. 2002 bibcode 2002nsps.conf...44S ref References Reflist External links http www.aip.org history mod A Pulsar Discovery First Optical Pulsar . Moments of Discovery, American Institute of Physics, 2007 Includes audio and teachers guides . DEFAULTSORT Optical Pulsar Category Pulsars optical pulsar Category Optical pulsars Category Star types ... more details
Italic title Infobox journal title Optical Materials cover File Optical Materials.gif editor G. Boulon discipline Optics , Chemistry , Physics peer reviewed formernames abbreviation Opt. Mater. publisher Elsevier country frequency Monthly history 1992 present openaccess license impact 1.678 impact year 2010 website http www.elsevier.com wps find journaldescription.cws home 522512 description link1 http www.sciencedirect.com science journal 09253467 link1 name Online access link2 link2 name RSS http rss.sciencedirect.com publication science 5596 atom JSTOR OCLC 39097987 LCCN 93023084 CODEN OMATET ISSN 0925 3467 eISSN 1873 1252 Optical Materials is a Peer review peer reviewed scientific journal that publishes original papers and review articles on the design, synthesis, characterisation and applications of materials, suitable for various optical instrument optical device s. The journal also publishes papers about physical and chemical properties of such materials and their applications. Abstracting and indexing Optical Materials is abstracted and indexed in the following databases Chemical Abstracts Service Current Contents Engineering, Computing & Technology Compendex Compendex Engineering Index Inspec Scopus References Reflist External links Official 1 http www.elsevier.com wps find journaldescription.cws home 522512 description Category Optics journals Category Monthly journals Category Publications established in 1992 Category Elsevier academic journals Category English language journals sci journal stub ... more details
Today s computers use the movement of electrons in and out of transistors to do logic. Optical or Photonic ... projects focus on replacing current computer components with optical equivalents, resulting in an optical ... term prospects for commercial optical computing, since optical components could be integrated into traditional computers to produce an optical or electronic hybrid. However, optoelectronic devices ... of messages. All optical computers eliminate the need for optical electrical optical OEO conversions ... which use principles of optical computing, e.g., optical correlators . Such devices can be used for detecting and tracking objects, for example. ref cite book title Optical Computing A Survey for Computer Scientists chapter Chapter 3 Optical Image and Signal Processing last Feitelson first Dror G. year 1988 publisher MIT Press location Cambridge, MA isbn 0262061120 ref Optical components for binary ... . To replace electronic components with optical ones, an equivalent optical transistor is required ... manner to the voltage response of an electronic transistor. Such an optical transistor ref Jain, K. and Pratt, Jr., G. W., Optical transistor , Appl. Phys. Lett., Vol. 28, 719 1976 . ref ref name jainprattpatent Jain, K. and Pratt, Jr., G. W., Optical transistors and logic circuits embodying the same , U.S. Pat. 4,382,660, issued May 10, 1983. ref can be used to create optical logic gates , ref ... of optical computers will they be able to compete with semiconductor based electronic computers in terms of speed, power consumption, cost, and form factor? Opponents of the idea that optical computers ... at low cost, low power, and high speed. For optical logic to be competitive beyond a few niche applications, major breakthroughs in non linear optical device technology would be required, or perhaps ... of optics is that it can reduce power consumption, but an optical communication system will typically use more power over short distances than an electronic one. This is because the shot noise of an optical ... more details
Image OpticalFlats157 03.jpg thumb Optical flats in case. About 1 inch 2.5 cm in diameter Image Optical flat interference fringes.jpg thumb Testing flatness of surfaces with optical flats. The lefthand surface is flat, the righthand surface is uneven. An optical flat is an optical grade piece of glass lapping lapped and polishing polished to be extremely flat on one or both sides, usually within a few millionths of an inch about 25 nanometres . They are used with a monochromatic light to determine the flatness of other optical surfaces by Interference wave propagation interference . ref cite book last English first R. E. editor first Albert G. editor last Ingalls editor link Albert Graham Ingalls title Amateur Telescope Making Amateur Telescope Making, Book Three publisher Scientific American date 1953 pages 156 162 chapter Optical Flats isbn ref When an optical flat is placed on another surface and illuminated, the light waves reflect off both the bottom surface of the flat and the surface it is resting on. The reflected waves interfere, creating a pattern of interference fringe s Newton s rings , visible as light and dark bands. The spacing between the fringes is smaller where the gap is changing more rapidly, indicating a departure from flatness in one of the two surfaces, in a similar way to the contour lines on a map. A flat surface is indicated by a pattern of straight, parallel ... by an arrow on the edge of the glass. Optical flats are sometimes given an optical coating and used ... cavity . Optical flats have uses in spectrophotometry as well. How interference fringes form Image Optical ... of the optical flat, the lower object a section of the test surface it is resting on. Unless ..., so the difference in the gap between the surfaces is one half wavelength. Image Optical flats in use.jpg thumb left Optical flats being used to calibrate metal parts. See also Optical contact bonding References reflist optics stub Category Optical devices de Planglas ... more details
Unreferenced date December 2009 An optical instrument either processes light wave s to enhance an image for viewing, or analyzes light waves or photon s to determine one of a number of characteristic properties. Image enhancement File Optical Devices England 1858.jpg thumb An illustration of some of the optical devices available for laboratory work in England in 1858. Further2 Viewing instrument The first optical instruments were telescope s used for magnification of distant images, and microscope s used for magnifying very tiny images. Since the days of Galileo and Van Leeuwenhoek , these instruments have been greatly improved and extended into other portions of the electromagnetic spectrum . The binoculars binocular device is a generally compact instrument for both eyes designed for mobile use. A camera could be considered a type of optical instrument, with the pinhole camera and camera obscura being very simple examples of such devices. Analysis Another class of optical instrument is used to analyze the properties of light or optical materials. They include Interferometer for measuring the Interference wave propagation interference properties of light waves Photometer for measuring light intensity Polarimeter for measuring dispersion or rotation of polarized light Spectrophotometer Reflectometer for measuring the reflectivity of a surface or object Refractometer for measuring refractive index of various materials, invented by Ernst Abbe Spectrometer or monochromator for generating or measuring a portion of the optical spectrum, for the purpose of chemical or material analysis ... be considered optical instruments as they analyse the color and intensity of the light emitted by a fluorochrome ... use refractometry to measure and analyze biomolecular interactions. Other optical devices Polarization controller See also Scientific instruments Commons category Optical devices DEFAULTSORT Optical Instrument Category Optical devices ar bg el es Instrumento ... more details
, and tracking response to therapies. Optical tomography found its application in industry as a sensor ... metrology for solar cell manufacturing , http www.zebraoptical.com Publications.html Sunrise Optical LLC , Proc. SPIE 7064, 70640A 2008 doi 10.1117 12.797541 ref . See also Optical coherence tomography Diffuse optical imaging Computed tomography laser mammography References reflist External links http www.imperial.ac.uk research photonics research topics tomog tomog.htm Optical tomography at Imperial College, London http www.medphys.ucl.ac.uk research borl index.htm Optical tomography at University ... on physics.org Category Optical imaging Category Neuroimaging science stub medical equipment stub ... more details
pp protected expiry 2012 09 07T23 12 29Z small yes Infobox company name big DCM Optical Holdings Ltd big br small parent to the Optical Express group small logo File OE logo 200px.jpg type Private genre ... treatments, healthcare services services revenue increase 204.67m 2011 ref name AA DCM Optical ... Optical Express Ltd br Optical Express Holdings Ltd br Cruach Capital Ltd br The Frame Zone Ltd br ... footnotes intl yes Optical Express is a retail optician optical services company in the United Kingdom. The Optical Express group of companies, subsidiaries of DCM Optical Holdings Ltd , operate in a wide range of healthcare services including the optical, dental and cosmetic industries. Optical ... of the optical goods market, of which Optical Express has a 6 share. ref Page 11 MINTEL Market Intelligence ... ref Overview and history Foundations File Optical Express store.jpg thumb upright An Optical Express store on Princes Street, Edinburgh Optical Express is part of the Optical Express Group, which aside from opticians, also operates in the optical, dental and cosmetic industries under the brand ... with one Optical Express branch based in Leith , Edinburgh . ref cite web last Conroy first Harry url http www.heraldscotland.com sport spl aberdeen inside business clear vision from optical express 1.450158 title INSIDE BUSINESS Clear vision from Optical Express Herald Scotland & 124 Sport & 124 SPL ... wide chain of 65 optical retail outlets, thus expanding into England for the first time. ref cite web url http case law.vlex.co.uk vid 55330016 title Optical Express Southern Ltd v Birmingham City Council ... Herald reported that Optical Express had 32 court judgements against it for failure to settle debts ... that it appeared to be a policy of Optical Express to pay debts late, however since the company has been trading without interruption, most of these amounts must by now have been paid. An Optical ... the true level of debt at Specialeyes that Optical Express had adopted. A PriceWaterhouseCoopers ... 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 optical medium. 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
Unreferenced stub auto yes date December 2009 Orphan date December 2009 Okaya Optical Co., Ltd. Okaya K gaku Kikai Kabushiki Gaisha was the manufacturer in the 1950s of Lord camera s, Vista binoculars , and other optical products. Category Defunct companies of Japan Category Photography companies of Japan Japan company stub fr Okaya ... more details
Infobox company name Optical 88 logo File Optical 88 Logo.png 220px caption The logo of Optical 88 type Eyeglasses making genre fate predecessor successor foundation Hong Kong , China Start date 1984 founder defunct location city Hong Kong location country China location locations area served nearly all of Southeast Asia , including Hong Kong , Macau , Guangzhou , Singapore , Thailand and Malaysia etc. key people industry Eyeglasses making products Frames and Corrective lens Lenses services Optical services revenue operating income net income aum assets equity owner num employees parent divisions subsid homepage http www.optical88.com lc hongkong.aspx Optical88.com footnotes intl Optical 88 zh c 88 is one of the famous eyewear stores in Hong Kong . It was established in 1984 , as a member of Stelux Group of Companies, who owns largest professional optical retail network in Hong Kong . ref http www.optical88.com lc About88.aspx Optical88.com ref Areas served Optical 88 s headquarters is located at Hong Kong , China dispersed all over Hong Kong Island , Kowloon and the New Territories while overseas stores are located at various countries and cities including Macau , Guangzhou , Singapore , Thailand and Malaysia etc. Products and Services Optical 88 s key products are eyeglasses , including sunglasses and the frames and Corrective lens lenses of these glasses. They mainly provide customers eyeglasses making services. See also Eyeglasses References reflist External links http www.optical88.com intro.htm Official Website Category Retail companies of Hong Kong HongKong company stub zh 88 ... more details
orphan date January 2010 Wikify date January 2010 The optical force is a phenomenon whereby beams of light can attract and repel each other. The force acts along an axis which is perpendicular to the light beams. Because of this, parallel beams can be induced to converge or diverge. The optical force works on a microscopic scale, and cannot currently be detected at larger scales. It was discovered by a team of Yale researches led by electrical engineer Hong Tang. ref http discovermagazine.com 2010 jan feb 083 Top 100 Stories of 2009 83 Like Magnets, Light Can Attract and Repel Itself , Discover magazine, from the January February 2010 special issue published online December 21, 2009 ref See also Optical lift References reflist DEFAULTSORT Optical force Category Force Category Spacecraft propulsion Category Aerospace engineering physics stub science stub ... more details
Unreferenced stub auto yes date December 2009 For the different scientific fields that consider optics Optics The optical field is a term used in physics and vector calculus to designate the electric field shown as E in the Electromagnetism electromagnetic wave equation which can be derived from Maxwell s Equations . In electromagnetic theory, the electromagnetic wave propagates such that both the magnetic field oscillation, and the electric field oscillation is perpendicular to the direction of propagation of the wave. As with any wave, the electromagnetic wave transports energy, thus the total energy density is shared between the constituent electric and magnetic fields. Since the electric field is considerably more effective at exerting forces and doing work on charges than the magnetic field, the electric field E is referred to as the optical field. DEFAULTSORT Optical Field Category Optics Optics stub ... 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
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