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Contents: Top - 0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

A

Abbe number -- Abbe prism -- aberration in optical systems -- absorption -- absorption spectrum -- active laser medium -- afterglow -- airglow -- Airy disk -- albedo -- Alexander's band -- alpenglow -- angle of incidence -- angle of reflection -- Arago spot -- asterism (astronomy) -- asterism (gemmology) -- atomic, molecular, and optical physics -- auroral light -- avalanche photodiode -- aventurescence -- In physics and optics, the Abbe number, also known as the V-number or constringence of a transparent material is a measure of the materials dispersion (variation of refractive index with wavelength). ... In optics, an Abbe prism, named for its inventor, the German physicist Ernst Abbe, is a type of constant deviation dispersive prism similar to a Pellin_Broca prism. ... Aberration in optical systems (lenses, prisms, mirrors or series of them intended to produce a sharp image) generally leads to blurring of the image. ... Absorption has a number of meanings: In physics, absorption is a process in which particles of some sort encounter another material and are taken up by or even disappear in it. ... An absorption spectrum is a diagram depicting the wavelengths of electromagnetic radiation absorbed by a material, usually a gas or a solute. ... Within a laser, the active laser medium is the material that exhibits optical gain. ... This article is about the afterglow atmospheric phenomenon. ... The airglow is the very weak emission of visible light by the earths atmosphere, which means that the night sky is never completely dark. ... Categories: Optics | Science stubs ... The albedo is a measure of reflectivity of a surface or body. ... Alpenglow ( German: Alpenglühen) is an optical phenomenon. ... An angle of incidence is the angle between a beam incident on a surface and the normal (line perpendicular to the surface at the point of incidence). ... An angle of incidence is the angle between a beam incident on a surface and the normal (line perpendicular to the surface at the point of incidence). ... In optics, an Arago spot is a bright point which, owing to diffraction, appears at the center of the shadow of a circular object in light from a point source. ... In astronomy, an asterism is a recognized pattern of stars seen in Earths sky which is neither an official constellation nor a true star cluster. ... Asterism on the surface of a sapphire In gemmology, an asterism is an optical phenomenon displayed by some rubies, sapphires, and other gems of an enhanced reflective area in the shape of a star on the surface of a cabochon cut from the stone. ... Atomic, molecular, and optical physics is the study of matter-matter and light-matter interactions on the scale of single atoms or structures containing a few atoms. ... Aurora borealis Polar aurorae are optical phenomena characterized by colorful displays of light in the night sky. ... Avalanche photodiodes (APDs) are photodetectors that can be regarded as the semiconductor analog to photomultipliers. ... In gemology, aventurescence (sometimes called aventurization) is an optical reflectance effect seen in certain gems. ...

B

Beer-Lambert law -- binoculars -- birefringence -- black body radiation -- Brewster's angle -- brightness temperature -- Brillouin scattering In optics, the Beer-Lambert law, also known as Beers law or the Beer-Lambert-Bouguer law is an empirical relationship in relating the absorption of light to the properties of the material the light is travelling through. ... Binoculars A set of binoculars (from Latin, bi-, two-, and oculus, eye) is a hand-held tool used to make distant objects appear closer by passing the image through two adjacent series of lenses, and erecting prisms. ... A calcite crystal laid upon a paper with some letters showing the double refraction Birefringence, or double refraction, is the division of a ray of light into two rays (the ordinary ray and the extraordinary ray) when it passes through certain types of material, such as calcite crystals, depending on... As the temperature decreases, the peak of the black body radiation curve moves to lower intensities and longer wavelengths. ... An illustration of the polaristion of light which is incident on an interface at Brewsters angle. ... Brightness temperature is a measure of the intensity of radiation thermally emitted by an object, given in units of temperature because there is a correlation between the intensity of the radiation emitted and physical temperature of the radiating body which is given by the Stefan-Boltzmann law. ... Brillouin scattering occurs when light in a medium (such as water or a crystal) interacts with density variations and changes its path. ...

C

camera -- camera lens -- camera lucida -- camera obscura -- candela -- cathodoluminescence -- caustics -- chatoyancy -- chromatic aberration -- chromatic polarization -- chromaticity -- chromaticity diagram -- chrominance -- circular dichroism -- coherence length -- coherence (physics) -- coherence time - collimated light -- color -- colorimetry -- color science -- confocal -- confocal laser scanning microscopy -- concave lens -- convex lens -- Cooke Triplet -- corner reflector -- critical angle -- crystal optics -- A camera is a device used to take pictures (usually photographs), either singly or in sequence, with or without sound, such as with video cameras. ... A photographic lens (or more correctly, objective) is an integrated system comprising one or more simple optical lens elements, used for a camera or microscope. ... A camera lucida is an optical device used as a drawing aid by artists. ... The camera obscura (Lat. ... The candela (symbol: cd, Latin for candle) is one of the seven SI base units. ... Cathodoluminescence is an optical and electrical television. ... The word caustics has several meanings depending upon the context in which it is used: In Greek language, from which this word originates, caustics means to burn or burning. In chemistry a caustic substance is one that eats away or chemically burns other materials by process of attacking it basically... In gemology, chatoyancy is an optical reflectance effect seen in certain gemstones. ... Chromatic aberration is caused by the dispersion of the lens material, the variation of its refractive index n with the wavelength of light. ... Chromaticity is the quality of a color as determined by its purity and dominant wavelength. ... The International Commission on Illumination (usually known as the CIE for its French-language name Commission Internationale de lEclairage) is the international authority on light, illumination, colour, and colour spaces. ... Chrominance (chroma for short) comprises the two components of a television signal that encode color information. ... Circular dichroism, or CD, is defined as the differential absorption of left and right hand circularly polarized light. ... In physics, coherence length is the propagation distance from a coherent source to a point where an electromagnetic wave maintains a specified degree of coherence. ... This article needs to be cleaned up to conform to a higher standard of quality. ... For an electromagnetic wave, coherence time is the time over which a propagating wave may be considered coherent. ... Collimated light is light whose rays are parallel. ... Color is an important part of the visual arts. ... Colorimetry is the science that describe colors in numbers, or provides a physical color match using a variety of measurement instruments, depending on the desired information about the color or colors the customer requires. ... For alternative meanings, see color (disambiguation). ... Confocal means having the same foci. ... Confocal laser scanning microscopy (CLSM or LSCM) is a valuable tool for obtaining high resolution images and 3-D reconstructions. ... concave lens diverging light rays A concave lens is a lens with inward-curving (concave) surfaces: the ends are wide, the middle is small. ... Convex lens converging light rays A convex lens is a lens that is curved outward (convex): the ends are narrow and the middle is wide. ... The Cooke triplet is a photographic lens design designed and patented in 1893 by Dennis Taylor who was employed as chief engineer by Cooke of York. ... Buoy in San Diego Harbor. ... In geometric optics, at a refractive boundary, the critical angle is the smallest angle of incidence at which total internal reflection occurs. ... Crystal optics is the branch of optics that describes the behaviour of light in anisotropic media, that is, media (such as crystals) in which light behaves differently depending on which direction the light is propagating. ...

D

dark state -- dichroic -- dichroic filter -- dichroic prism -- diffraction -- diffraction grating -- diffractive optics -- dispersion (optics) -- double refraction -- double-slit experiment -- The dark state is an interaction between matter and light, in which light can be slowed down or even stopped. ... In optics, the term dichroic has two related but distinct meanings. ... Halogen light bulb capsule (center) with an integrated dichroic reflector. ... A dichroic prism is a prism that splits light into two beams of differing wavelength (colour). ... Diffraction is the apparent bending and spreading of waves when they meet an obstruction. ... A huge diffraction grating. ... Diffraction is the apparent bending and spreading of waves when they meet an obstruction. ... In optics, dispersion is a phenomenon that causes the separation of a wave into spectral components with different frequencies, due to a dependence of the waves speed on its frequency. ... A calcite crystal laid upon a paper with some letters showing the double refraction Birefringence, or double refraction, is the division of a ray of light into two rays (the ordinary ray and the extraordinary ray) when it passes through certain types of material, such as calcite crystals, depending on... The double-slit experiment consists of letting light diffract through two slits producing fringes on a screen. ...

E

EDFA -- electro-optic effect -- electroluminescence -- electromagnetic radiation -- electromagnetic spectrum -- electromagnetic wave -- electronic displays (science of) -- elve -- emission spectrum -- eyeglass prescription -- etalon -- evanescent wave eye -- excimer laser -- In telecommunication, an optical amplifier is a device that amplifies an optical signal directly, without the need to convert it to an electrical signal, or amplify it electrically, and reconvert it to an optical signal. ... The electro-optic effect is a change in the optical properties of a material in response to an electric field that varies slowly compared with the frequency of light. ... Electroluminescence is an optical phenomenon and electrical phenomenon where a material such as a natural blue diamond emits light when an electric current is passed through it. ... Electromagnetic radiation is a propagating wave in space with electric and magnetic components. ... The electromagnetic spectrum encompasses all possible wavelengths of electromagnetic radiation. ... Electromagnetic radiation is a propagating wave in space with electric and magnetic components. ... For alternate meanings, see Lightning (disambiguation). ... A materials emission spectrum is the amount of electromagnetic radiation of each frequency it emits when it is heated (or more generally when it is excited). ... This article describes the optics of an ordinary eyeglass prescription, which is used to correct small refractive errors in the optical system of the eye. ... In optics, a Fabry-Perot interferometer or etalon is typically made of a transparent plate with two reflecting surfaces, or two parallel highly-reflecting mirrors. ... An evanescent wave is an electromagnetic wave that decays exponentially with distance. ... An eye is an organ that detects light. ... An excimer laser is a form of ultraviolet chemical laser which is commonly used in eye surgery and semiconductor manufacturing. ...

F

f-number -- fabrication and testing (optical components) -- Faraday effect -- far point -- fata Morgana -- Fermat's principle -- fiber amplifier -- fiber optics -- filter (optics) -- Fizeau-Foucault apparatus -- fluorescence -- focal length -- focal point (optics) -- focal point (primary) -- focal point (secondary) -- focus -- Fourier optics -- Fraunhofer diffraction -- Fraunhofer line -- free-space optical communication -- Augustin-Jean Fresnel -- Fresnel equations -- Fresnel lens -- Fresnel number -- Fresnel reflection -- Fresnel zone -- A 35mm lens set to f/11, as indicated by the white dot above the f-stop scale on the aperture ring In photography the f-number (focal ratio) expresses the diameter of the diaphragm aperture in terms of the effective focal length of the lens. ... In physics, the Faraday effect or Faraday rotation is an interaction between light and a magnetic field. ... In visual optics, the far point is the point at which an object must be placed along the optical axis for its image to be focused on the retina when the eye is not accommodating. ... A fata Morgana, named after Morgan le Fay, the faery shapeshifting half-sister of King Arthur, is a mirage, an optical phenomenon which results from a temperature inversion. ... Fermats principle assures that the angles given by Snells law always reflect lights quickest path between P and Q. Fermats principle in optics states: This principle was first stated by Pierre de Fermat. ... In telecommunication, an optical amplifier is a device that amplifies an optical signal directly, without the need to convert it to an electrical signal, or amplify it electrically, and reconvert it to an optical signal. ... Fiber Optic strands An optical fiber in American English or fibre in British English is a transparent thin fiber for transmitting light. ... An optical filter is a device which selectively transmits light having certain properties (often, a particular range of wavelengths, i. ... The Fizeau-Foucault apparatus (1850) was designed by the French physicists Hippolyte Fizeau and Léon Foucault for measuring the speed of light. ... Fluorescence induced by exposure to ultraviolet light in vials containing various sized cadmium selenide (CdSe) quantum dots. ... The focal point F and focal length f of a positive lens, a negative lens, a concave mirror, and a convex mirror. ... The word focus (pl. ... To explain the basic principle of Fourier optics, it might be useful to consider the analogue with acoustics: If an arbitrary sound is analyzed through a spectrum analyzer, you will get all the different frequencies and their individual amplitudes that, together, form the sound. ... Fraunhofer diffraction is diffraction of light through an aperture for small values of the Fresnel number, F<<1. ... Solar Fraunhofer lines In physics and optics, the Fraunhofer lines are a set of spectral lines named for the German physicist Joseph von Fraunhofer (1787--1826). ... Free-space optical communication involves the use of optical links across the space between two points, either within the Earths atmosphere, or in outer space. ... Augustin Fresnel Augustin-Jean Fresnel (pronounced [] in AmE, [] in French) (May 10, 1788 – July 14, 1827), was a French physicist who contributed significantly to the establishment of the wave theory of light and optics. ... The Fresnel equations, deduced by Augustin-Jean Fresnel, describe the behaviour of light when moving between media of differing refractive indices. ... Lens of a lighthouse in Rozewie A Fresnel lens is a type of lens invented by Augustin-Jean Fresnel. ... In optics, Fresnel reflection is the reflection of a portion of incident light at a discrete interface between two media having different refractive indices. ... In optics and radio communications, a Fresnel zone (pronounced as FRA-nel Zone), named for physicist Augustin-Jean Fresnel, is one of a (theoretically infinite) number of a concentric ellipsoids of revolution which define volumes in the radiation pattern of a (usually) circular aperture. ...

G

Gaussian beam -- gegenschein -- geometrical optics -- glory (optical phenomenon) -- gradient index lens -- gradient index optics -- guided-wave optics: see waveguide -- In optics, a Gaussian beam, named in honor of Carl Friedrich Gauss (rhymes with house), is a beam of light whose electric field intensity distribution is a Gaussian function. ... Gegenschein (German for counterglow) is a faint brightening of the night sky in the region of the zodiac directly opposite the Sun caused by reflection of sunlight by small dust particles that lie in the plane of the Solar system. ... See also list of optical topics. ... NASA photo A glory is an optical phenomenon produced by light reflected toward its source by a cloud of uniformly-sized water droplets. ... Gradient index optics is the branch of optics covering optical effects produced by a gradual variation of the refractive index of a material. ... Gradient index optics is the branch of optics covering optical effects produced by a gradual variation of the refractive index of a material. ... In physics, optics, and telecommunication, a waveguide is an inhomogeneous (structured) material medium that confines and guides a propagating electromagnetic wave. ...

H

Haidinger's brush -- halo (optical phenomenon) -- Helium-neon laser -- history of lensmaking -- holography -- human visual system -- Huygens' principle -- Simulated appearance of Haidingers brush for vertically polarized light. ... Halo around the sun at the South Pole (NOAA) Halos are optical phenomena that appear near or around the Sun or Moon, and sometimes near other strong light sources such as street lights. ... A helium-neon laser, usually called a HeNe laser, is a small gas laser of a type often used in laboratory demonstrations of optics. ... This page is a candidate for speedy deletion. ... Holography (from the Greek, Όλος-holos whole + γραφή-graphe writing) is the science of producing holograms, an advanced form of photography that allows an image to be recorded in three dimensions. ... Huygens principle (named for Dutch physicist Christiaan Huygens) is a method of analysis applied to problems of wave propagation. ...

I

illumination engineering -- image processing -- incandescence -- information theory -- integrated optics -- interference -- interferometry -- inverse-square law -- iridescence -- International Commission on Illumination-- This article needs to be cleaned up to conform to a higher standard of quality. ... Molten glassy material glows orange with incandescence in a vitrification experiment. ... Information theory is a branch of the mathematical theory of probability and mathematical statistics that quantifies the concept of information. ... Interference of two circular waves - Wavelength (decreasing bottom to top) and Wave centers distance (increasing to the right). ... Interferometry is the applied science of combining two or more input points of a particular data type, such as optical measurements, to form a greater picture based on the combination of the two sources. ... This diagram shows how the law works. ... The iridescence of the Blue Morpho butterfly wings. ... The International Commission on Illumination (usually known as the CIE for its French-language name Commission Internationale de lEclairage) is the international authority on light, illumination, colour, and colour spaces. ...

J

Jones calculus -- In optics one can describe polarisation using the Jones calculus, invented by R. C. Jones in 1941. ...

K

Kerr cell -- Kerr effect -- Kerr-lens modelocking -- knife-edge effect -- Rev. ... The Kerr effect or the quadratic electro-optic effect is a change in the refractive index of a material in response to the intensity of an external electric field. ... Kerr-lens modelocking is a method of modelocking lasers via a nonlinear optical process known as the optical Kerr effect. ... In electromagnetic wave propagation, the knife-edge effect is a redirection by diffraction of a portion of the incident radiation that strikes a well-defined obstacle such as a mountain range or the edge of a building. ...

L

laser -- laser construction -- laser applications -- lens (optics) -- light -- light bulb -- light-emitting diode -- light meter -- liquid-crystal display -- liquid scintillation counting -- list of fiber optic terms -- list of indices of refraction -- list of wave topics -- luminance -- luminiferous aether -- luminosity -- luminous intensity -- lumen -- lux Laser (US Air Force) A LASER (Light Amplification by Stimulated Emission of Radiation) is an optical device which uses a quantum mechanical effect called stimulated emission (discovered by Einstein while researching the photoelectric effect) in order to generate a coherent beam of light from a lasing medium of controlled purity... A laser system generally consists of three important parts: An energy source (usually referred to as the pump or pump source); A gain medium or laser medium; A mirror, or system of mirrors, forming an optical resonator. ... Soon after the invention of the laser in 1960, it was described as a solution in search of a problem. However, since that time, the laser has found a place as a useful tool in many scientific, military, medical and industrial applications. ... A lens is a device for either concentrating or diverging light, usually formed from a piece of shaped glass. ... Prism splitting light Light is electromagnetic radiation with a wavelength that is visible to the eye, or in a more general sense, any electromagnetic radiation in the range from infrared to ultraviolet. ... The incandescent light bulb uses a glowing wire filament heated to white-hot by electrical resistance, to generate light (a process known as thermal radiation). ... Various light-emitting diodes (5 mm reds, 3 mm greens and yellows) A light-emitting diode (LED) is a semiconductor device that emits incoherent narrow-spectrum light when electrically biased in the forward direction. ... Photograph of a handheld digital ambient light meter, showing an f-stop of 5. ... LCD redirects here. ... Liquid scintillation counting is a standard laboratory method in the life-sciences for measuring radiation from beta-emitting nuclides. ... This is a list of fiber optic terms derived from the Glossary of Telecommunication Terms published as Federal Standard 1037C. Please see the Federal Standard article for copyright-related issues, as not all parts of the source document are in the public domain. ... Many materials have a well-characterized refractive index, but these indices depend strongly upon the wavelength of light. ... This is a list of wave topics, by Wikipedia page. ... The word luminance, a synonym for luminosity, means emitting or reflecting light. ... The luminiferous aether: it was hypothesised that the Earth moves through a medium of aether that carries light In the late 19th century the luminiferous aether (light-bearing aether), or ether, was a substance postulated to be the medium for the propagation of light. ... // In General Physics In general physics, luminosity (more properly called luminance) is the density of luminous intensity in a given direction. ... Luminous intensity is a measure of the energy emitted by a light source in a particular direction. ... In physics, specifically photometry (optics), the lumen (symbol: lm) is the SI derived unit of luminous flux. ... The lux (symbol: lx) is the SI derived unit of illuminance or illumination. ...

M

magnifying glass -- material science - optical properties -- metamerism -- Michelson-Morley experiment -- micro-optics -- microphotonics -- microscope -- Mie scattering -- mirage -- mirror -- modelocking -- modern optics -- monochromator -- monocular -- A magnifying glass A magnifying glass is a single convex lens which is used to produce a magnified image of an object. ... Metamerism is a psychophysical phenomenon commonly defined incompletely as two samples which match when illuminated by a particular light source and then do not match when illuminated by a different light source. ... The Michelson-Morley experiment, one of the most important and famous experiments in the history of physics, was performed in 1887 at what is now Case Western Reserve University, and is considered to be the first strong evidence against the theory of a luminiferous aether. ... Microphotonics is a branch of technology that deals with directing light on a microscopic scale. ... 1852 microscope Compound microscope made by John Cuff in 1750 A microscope (Greek: micron = small and scopos = aim) is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. ... The Mie theory also called Lorenz-Mie theory is a complete mathematical-physical theory of the scattering of electromagnetic radiation by spherical particles, developed by Gustav Mie in 1908. ... A road mirage, a type of inferior mirage A mirage is an optical phenomenon which often occurs naturally. ... A mirror is a reflective surface that is smooth enough to form an image. ... Modelocking is a technique in optics by which a laser can be made to produce pulses of light of extremely short duration, on the order of picoseconds (10-12s) or femtoseconds (10-15s). ... A monochromator is an optical device that transmits a mechanically selectable narrow band of wavelengths of light chosen from a wider range of wavelengths available at the input. ... A monocular is a modified refracting telescope used to magnify the images of distant objects by passing light through a series of lenses and prisms; the use of prisms results in a lightweight telescope. ...

N

Natural Color System -- Newton's rings -- non-imaging optics -- nonlinear optics -- normal lens -- numerical aperture -- The Natural Color System (NCS) is a color system designed by the Scandinavian Colour Institute (sic, color is spelled differently in the name of the standard and the English translation of their name). ... The phenomenon of Newtons rings is an interference pattern caused by the reflection of light between two surfaces - a spherical surface and an adjacent flat surface. ... Nonlinear optics is the branch of optics that describes the behaviour of light in nonlinear media, that is, media in which the polarization P responds nonlinearly to the electric field E of the light. ... In photography and cinematography a normal lens is a lens that generates images that are generally held to have a natural perspective compared with lenses with longer or shorter focal lengths. ... Numerical aperture is a technical term of multiple uses: Numerical aperture of optical telecommunication fiber Numerical aperture in microscopy This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ...

O

optical bench -- optical coating -- optical communication -- optical computer -- optical data storage (science of) -- optical depth -- optical disc -- optical distance -- optical engineering -- optical fiber -- Optical Fiber Connector -- optical illusion -- optical instrument -- optical lens design -- optical modeling and simulation -- optical path length -- optical pattern recognition -- optical phenomenon -- optical processor -- optical resonator -- optical spectrum -- optical tweezers -- optical waveguide -- optical window -- optics -- optoelectronics An optical coating is a thin layer of material placed on an optical component such as a lens or mirror which alters the way in which the optic reflects and transmits light. ... Optical communication is any form of telecommunication that uses light as the transmission medium. ... An optical computer is a computer that performs its computation with photons or polaritons as opposed to the more traditional electron-based computation. ... Optical depth is a measure of transparency, and is defined as the fraction of radiation that is scattered between a point and the observer. ... In computing, sound reproduction, and video, an optical disc is flat, circular, usually polycarbonate disc whereon data is stored. ... In optics and telecommunication, the term optical path length has the following meanings: In a medium of constant refractive index, n , the product of the geometric distance and the refractive index. ... Optical engineering is the field of study which focuses on applications of optics. ... Optical fibers An optical fiber is a transparent thin fiber, usually made of glass or plastic, for transmitting light. ... An Optical Fiber Connector constitutes a fiber-to-fiber interconnection and aligns the fiber core of two optical fibers. ... An optical illusion is any illusion that deceives the human visual system into perceiving something that is not present or incorrectly perceiving what is present. ... ... In optics and telecommunication, the term optical path length has the following meanings: In a medium of constant refractive index, n , the product of the geometric distance and the refractive index. ... An optical phenomenon is any observable event which results from the interaction of light and matter. ... The optical spectrum (light or visible spectrum) is the portion of the electromagnetic spectrum that is visible to the human eye. ... Optical tweezers are the application of a laser beam to physically move very small translucent objects. ... An optical waveguide is a form of a dielectric waveguide, that is capable of guiding an optical signal. ... In astronomy, the optical window is that portion of the electromagnetic spectrum that passes through the atmosphere all the way to the ground. ... See also list of optical topics. ... Optoelectronics is the study and application of electronic devices that interact with light. ...

P

pattern recognition -- pentaprism -- penumbra -- phase (waves) -- phosphorescence -- photodiode -- photoelectric effect -- photographic lens -- photography (science of) -- photometry -- photomultiplier -- photon -- photonic crystal -- photonics -- photorefractive effect -- photoresistor -- physical optics -- pleochroism -- Pockels effect -- polarimeter -- polarization -- Polaroid -- population inversion -- Porro prism -- prime lens -- principle of least time -- prism (optics) -- For the William Gibson novel, see: Pattern Recognition (novel). ... A pentaprism is a five-sided reflecting prism used to deviate a beam of light by 90°. The beam reflects inside the prism twice, allowing the transmission of an image through a right angle without inverting it (i. ... Umbra & penumbra The penumbra (Latin for mid-shadow) is the portion of a shadow that results from the source of illumination being only partially blocked. ... Waves with the same phase Waves with different phases The phase of a wave relates the position of a feature, typically a peak or a trough of the waveform, to that same feature in another part of the waveform (or, which amounts to the same, on a second waveform). ... Phosphorescence is the result of a radiative (light emitting) transition involving a change in the spin multiplicity of (in most cases) a molecule from excited state singlet to excited state triplet. ... A photodiode is an electronic component and a type of photodetector. ... The photoelectric effect is the emission of electrons from a surface (usually metallic) upon exposure to, and absorption of, electromagnetic radiation (such as visible light and ultraviolet radiation). ... A photographic lens (or more correctly, objective) is an integrated system comprising one or more simple optical lens elements, used for a camera or microscope. ... This page provides information on the science used in all aspects of photography: the camera, its lenses, physical operation of the camera, electronic camera internals, and the process of developing film. ... In astronomy, photometry is the measurement of the flux or intensity of an astronomical objects electromagnetic radiation. ... Photomultipliers, or photomultiplier tubes (PMT) are extremely sensitive detectors of light in the ultraviolet, visible and near infrared. ... For the Science Fiction missile, as seen in Star Trek, see Photon torpedo. ... The opal in this bracelet contains a natural periodic microstructure responsible for its iridescent color. ... Photonics is the science and technology of generating and controlling photons, particularly in the visible and near infra-red light spectrum. ... The photorefractive effect is a nonlinear optical effect seen in certain crystals and other materials that respond to light by altering their refractive index. ... A photoresistor is an electronic component whose resistance decreases with increasing incident light intensity. ... Pleochroism is an optical phenomenon where due to double refraction of light by a colored gem or crystal, the light is divided into two paths which are polarized at a 90° angle to each other. ... The Pockels effect, or Pockels electro-optic effect, is the production of birefringence in an optical medium induced by a slowly-varying electric field. ... A polarimeter is a scientific instrument for measuring the rotation of the plane of polarized light as it passes through a sample of a compound which exhibits optical activity. ... This article treats polarization in electrodynamics. ... Polaroid® (a trademark of the Polaroid Corporation) is the name of a type of synthetic plastic sheet which is used to polarise light. ... In physics, specifically statistical mechanics, the concept of population inversion is of fundamental importance in laser science because the production of a population inversion is a necessary step in the workings of a laser. ... In optics, a Porro prism, named for its inventor Ignazio Porro, is a type of reflection prism used in optical instruments to alter the orientation of an image. ... Categories: Stub | Lenses by type | Optics ... Fermats principle assures that the angles given by Snells law always reflect lights quickest path between P and Q. Fermats principle in optics states: This principle was first stated by Pierre de Fermat. ... If a shaft of light entering a prism is sufficiently small such that the coloured edges meet, a spectrum results In optics, a prism is a device used to refract light, reflect it or break it up (to disperse it) into its constituent spectral colours (colours of the rainbow), traditionally...

Q

Q-switching -- quantum optics -- Q-switching, sometimes known as giant pulse formation, is a technique discovered circa 1962 by R.W. Hellwarth and F.J. McClung using electrically switched Kerr cell shutters and is a technique by which a laser can be made to produce a pulsed output beam. ... Quantum optics is a field of research in physics, dealing with the application of quantum mechanics to phenomena involving light and its interactions with matter. ...

R

radiometry -- rainbow -- Raman amplification -- Raman amplifier -- Rayleigh criterion -- Rayleigh scattering -- ray tracing -- ray transfer matrix analysis -- reflecting telescope -- reflection (optics) -- refracting telescope -- refraction -- reflection coefficient -- refractive index -- refractometer -- retroreflector -- RGB color model In telecommunication and physics, radiometry is the science of radiation measurement. ... A rainbow arches over the gardens at the Canada pavilion at Epcot in Walt Disney World, Lake Buena Vista, Florida, United States. ... In telecommunication, an optical amplifier is a device that amplifies an optical signal directly, without the need to convert it to an electrical signal, or amplify it electrically, and reconvert it to an optical signal. ... Resolving power is the ability of a microscope or telescope to measure the angular separation of images that are close together. ... Rayleigh scattering causing a sunset Rayleigh scattering (named after Lord Rayleigh) is the scattering of light by particles smaller than the wavelength of the light. ... A ray traced scene. ... Ray transfer matrix analysis (also known as ABCD matrix analysis) is a type of ray tracing technique used in the design of some optical systems, particularly lasers. ... Ritchey 24 reflecting telescope A reflecting telescope (reflector) is an optical telescope which uses mirrors, rather than lenses, to reflect light. ... The reflection of sunlight on water Reflection is the abrupt change in direction of a wave front at an interface between two dissimilar media so that the wave front returns into the medium from which it originated. ... The 50 cm refractor at Nice Observatory. ... Refraction in a Perspex (acrylic) block. ... The term reflection coefficient is used in physics and electrical engineering when wave propagation in a medium containing discontinuities is considered. ... The parameter used to describe the interaction of electromagnetic radiation with matter is the complex index of refraction, , which is a combination of a real part and an imaginary part. ... A retroreflector is a device that sends light or other radiation back where it came from regardless of the angle of incidence, unlike a mirror, which does that only if the mirror is exactly perpendicular to the light beam. ... The RGB color model utilizes the additive model in which red, green, and blue light are combined in various ways to create other colors. ...

S

scattering -- scintillator -- scintillation -- Sellmeier equation -- shadow -- slit experiment -- Willebrord Snell -- Snell's law -- speckle pattern -- speckle interferometry -- spectroscopy -- speed of light -- spontaneous emission -- sprite (optical phenomenon) -- statistical optics -- stereoscopy -- stimulated emission -- Stokes parameters -- sun dog -- sunlight -- sylvanshine -- synchrotron radiation -- In particle physics, scattering is a class of phenomena by which particles are deflected by collisions with other particles. ... A scintillator is a device or substance that absorbs high energy (ionizing) electromagnetic or charged particle radiation then, in response, fluoresces photons at a characteristic Stokes-shifted (longer) wavelength, releasing the previously absorbed energy. ... The term Scintillation has several different meanings, including: Atmospheric induced Scintillation effects which influence astronomical observations. ... In optics, the Sellmeier equation is an empirical relationship between refractive index n and wavelength λ for a particular transparent medium. ... Shadows on a pavement A shadow is a dark shape, e. ... Single-slit diffraction pattern In physics, there are many experiments which constitute of shining light upon thin slits, and observing the wave behaviour of light past these slits: Single-slit experiments which lead to diffraction. ... Willebrord Snell. ... Snells law is the simple formula used to calculate the refraction of light when travelling between two media of differing refractive index. ... In optical systems, a speckle pattern is a field-intensity pattern produced by the mutual interference of partially coherent beams that are subject to minute temporal and spatial fluctuations. ... Speckle interferometry is an image processing technique used in astronomy that can dramatically increase the resolution of ground-based telescopes. ... Spectroscopy is the study of spectra, that is, the dependence of physical quantities on frequency. ... Cherenkov effect in a swimming pool nuclear reactor. ... Spontaneous emission is the process by which a molecule in an excited state drops to the ground state, resulting in the creation of a photon. ... Stereoscopy, stereoscopic imaging or 3-D (three-dimensional) imaging is a technique to create the illusion of depth in a photograph, movie, or other two-dimensional image, by presenting a slightly different image to each eye. ... In optics, stimulated emission is the process by which, when perturbed by a photon, matter may lose energy resulting in the creation of another photon. ... It is common to describe incoherent or partially polarized radiation in terms of its total intensity (I), (fractional) degree of polarization (p), and the shape parameters of the polarization ellipse. ... A sundog is a relatively common atmospheric optical phenomenon associated with the reflection/refraction of sunlight by the numerous small ice crystals that make up cirrus or cirrostratus clouds. ... Sunlight is also the trade name of the worlds first packaged, branded laundry soap producted by Lever Brothers. ... Sylvanshine is an optical phenomenon in which dew-covered trees of species whose leaves are wax-covered retroreflects beams of light, as from a vehicles headlights, sometimes causing trees to appear to be snow-covered at night during the summer. ... Synchrotron radiation is electromagnetic radiation, similar to cyclotron radiation, but generated by the acceleration of relativistic electrons (i. ...

T

telescope -- thermal physics - radiative heat transfer -- thin-film optics -- total internal reflection -- transparency (optics) -- transverse mode -- 50 cm refracting telescope at Nice Observatory. ... Thin-film optics is the branch of optics which deals with very thin structured layers of different materials. ... The larger the angle to the normal, the smaller is the fraction of light transmitted, until the angle when total internal reflection occurs. ... In optics, transparency is the property of being transparent, or allowing light to pass. ... A transverse mode of a beam of electromagnetic radiation is a particular intensity pattern of radiation measured in a plane perpendicular (i. ...

U

ultraviolet catastrophe -- umbra -- Umov effect -- The ultraviolet catastrophe, also called the Rayleigh-Jeans catastrophe, was a prediction of early 20th century classical physics that an ideal black body at thermal equilibrium will emit radiation with infinite power. ... A different sense of the word umbra, used in mathematics, is explained in the article titled umbral calculus. ...

W

waveguide -- wavelength -- wavelength division multiplexing -- wave plate -- wide-angle lens -- In physics, optics, and telecommunication, a waveguide is an inhomogeneous (structured) material medium that confines and guides a propagating electromagnetic wave. ... The wavelength is the distance between repeating units of a wave pattern. ... In telecommunications wavelength division multiplexing (WDM) is a technology which multiplexes several optical carrier signals on a single optical fibre by using different wavelengths (colours) of laser light to carry different signals. ... A wave plate is an optical device that alters the polarization state of a light wave travelling through it. ... In photography and cinematography, a wide-angle lens is a lens whose focal length is shorter than the focal length of a normal lens. ...

Z

Zeeman effect -- Zeiss Tessar -- zodiacal light -- zone plate -- zoom lens -- The Zeeman effect is the split of a spectral line into several components in the presence of a magnetic field. ... The Zeiss Tessar is a famous photographic lens design conceived by Paul Rudolph in 1902. ... The zodiacal light is a faint glow which appears in a band along the ecliptic or zodiac from the vicinity of the Sun. ... An example of a zone plate. ... A Canon Inc. ...