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List Of Laser Types
This is a list of laser types, their operational wavelengths, and their applications. Thousands of kinds of laser are known, but most of them are used only for specialized research. Overview Gas lasers Chemical lasers Used as directed-energy weapons. Dye lasers Metal-vapor lasers Solid-state lasers Semiconductor lasers Other types of lasers See also * Laser construction *List of laser articles This is a list of laser topics. A * 3D printing, additive manufacturing * Abnormal reflection * Above-threshold ionization * Absorption spectroscopy * Accelerator physics * Acoustic microscopy * Acousto-optic deflector * Acousto-optic ... Notes Further references *Silfvast, William T. ''Laser fundamentals'', Cambridge University Press, 2004. *Weber, Marvin J. ''Handbook of laser wavelengths'', CRC Press, 1999. {{DEFAULTSORT:Laser Types ...
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Laser Glass Slab
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The first laser was built in 1960 by Theodore H. Maiman at Hughes Research Laboratories, based on theoretical work by Charles Hard Townes and Arthur Leonard Schawlow. A laser differs from other sources of light in that it emits light which is ''coherent''. Spatial coherence allows a laser to be focused to a tight spot, enabling applications such as laser cutting and lithography. Spatial coherence also allows a laser beam to stay narrow over great distances (collimation), enabling applications such as laser pointers and lidar (light detection and ranging). Lasers can also have high temporal coherence, which allows them to emit light with a very narrow spectrum. Alternatively, temporal coherence can be used to produce ultrashort pulses of light ...
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Lithography
Lithography () is a planographic method of printing originally based on the immiscibility of oil and water. The printing is from a stone (lithographic limestone) or a metal plate with a smooth surface. It was invented in 1796 by the German author and actor Alois Senefelder and was initially used mostly for musical scores and maps.Meggs, Philip B. A History of Graphic Design. (1998) John Wiley & Sons, Inc. p 146 Carter, Rob, Ben Day, Philip Meggs. Typographic Design: Form and Communication, Third Edition. (2002) John Wiley & Sons, Inc. p 11 Lithography can be used to print text or images onto paper or other suitable material. A lithograph is something printed by lithography, but this term is only used for fine art prints and some other, mostly older, types of printed matter, not for those made by modern commercial lithography. Originally, the image to be printed was drawn with a greasy substance, such as oil, fat, or wax onto the surface of a smooth and flat limestone pla ...
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Dental Laser
A dental laser is a type of laser designed specifically for use in oral surgery or dentistry. In the United States, the use of lasers on the gums was first approved by the Food and Drug Administration in the early 1990s, and use on hard tissue like teeth or the bone of the mandible gained approval in 1996. Several variants of dental lasers are in use with different wavelengths and these mean they are better suited for different applications. Soft tissue lasers *Diode lasers *Carbon dioxide lasers * Nd:YAG laser Diode lasers wavelengths in the 810–1,100 nm range are poorly absorbed by the soft tissues such as the gingivae, and cannot be used for soft tissue cutting or ablation. Instead, the distal end of diode’s glass fiber is charred (by burned ink or by burned corkwood, etc.) and the char is heated by the 810-1,100 nm laser beam, which in turn heats up the glass fiber’ tip. The soft tissue is cut, on contact, by the hot charred glass tip and not by the laser beam itse ...
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Surgery
Surgery ''cheirourgikē'' (composed of χείρ, "hand", and ἔργον, "work"), via la, chirurgiae, meaning "hand work". is a medical specialty that uses operative manual and instrumental techniques on a person to investigate or treat a pathological condition such as a disease or injury, to help improve bodily function, appearance, or to repair unwanted ruptured areas. The act of performing surgery may be called a surgical procedure, operation, or simply "surgery". In this context, the verb "operate" means to perform surgery. The adjective surgical means pertaining to surgery; e.g. surgical instruments or surgical nurse. The person or subject on which the surgery is performed can be a person or an animal. A surgeon is a person who practices surgery and a surgeon's assistant is a person who practices surgical assistance. A surgical team is made up of the surgeon, the surgeon's assistant, an anaesthetist, a circulating nurse and a surgical technologist. Surgery usually ...
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Laser Beam Welding
Laser beam welding (LBW) is a welding technique used to join pieces of metal or thermoplastics through the use of a laser. The beam provides a concentrated heat source, allowing for narrow, deep welds and high welding rates. The process is frequently used in high volume and precision requiring applications using automation, as in the automotive and aeronautics industries. It is based on keyhole or penetration mode welding. Operation Like electron-beam welding (EBW), laser beam welding has high power density (on the order of 1 MW/cm2) resulting in small heat-affected zones and high heating and cooling rates. The spot size of the laser can vary between 0.2 mm and 13 mm, though only smaller sizes are used for welding. The depth of penetration is proportional to the amount of power supplied, but is also dependent on the location of the focal point: penetration is maximized when the focal point is slightly below the surface of the workpiece A continuous or pulsed laser ...
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Laser Cutting
Laser cutting is a technology that uses a laser to vaporize materials, resulting in a cut edge. While typically used for industrial manufacturing applications, it is now used by schools, small businesses, architecture, and hobbyists. Laser cutting works by directing the output of a high-power laser most commonly through optics. The laser optics and CNC (computer numerical control) is used to direct the laser beam to the material. A commercial laser for cutting materials uses a motion control system to follow a CNC or G-code of the pattern to be cut onto the material. The focused laser beam is directed at the material, which then either melts, burns, vaporizes away, or is blown away by a jet of gas, leaving an edge with a high-quality surface finish. History In 1965, the first production laser cutting machine was used to drill holes in diamond dies. This machine was made by the Western Electric Engineering Research Center. In 1967, the British pioneered laser-assisted ox ...
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Carbon Dioxide Laser
The carbon-dioxide laser (CO2 laser) was one of the earliest gas lasers to be developed. It was invented by Kumar Patel of Bell Labs in 1964 and is still one of the most useful types of laser. Carbon-dioxide lasers are the highest-power continuous-wave lasers that are currently available. They are also quite efficient: the ratio of output power to pump power can be as large as 20%. The CO2 laser produces a beam of infrared light with the principal wavelength bands centering on 9.6 and 10.6  micrometers (μm). Amplification The active laser medium (laser gain/ amplification medium) is a gas discharge which is air- or water-cooled, depending on the power being applied. The filling gas within a sealed discharge tube consists of around 10–20% carbon dioxide (), around 10–20% nitrogen (), a few percent hydrogen () and/or xenon (Xe), and the remainder is helium (He). A different mixture is used in a ''flow-through'' laser, where is continuously pumped through it. The spec ...
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TEA Laser
A TEA laser is a gas laser energized by a high voltage electrical discharge in a gas mixture generally at or above atmospheric pressure. The most common types are carbon dioxide lasers and excimer lasers, both used extensively in industry and research; less common are nitrogen lasers. The acronym "TEA" stands for Transversely Excited Atmospheric. History Invention The carbon dioxide (CO2) TEA laser was invented in the late 1960s by Jacques Beaulieu working at the Defence Research and Development Canada at Valcartier in Quebec, Canada. The development was kept secret until 1970, when brief details were published. In 1963, C. Kumar N. Patel, working at Bell Telephone Laboratories, first demonstrated laser output at 10.6 µm from a low pressure RF-excited CO2 gas discharge. With the addition of nitrogen and helium and using a DC electrical discharge, CW powers of around 100 W were achieved. By pulsing the discharge using higher voltages, or Q-switching using a ro ...
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Superradiant Laser
A superradiant laser is a laser that does not rely on a large population of photons within the laser cavity to maintain coherence. Rather than relying on photons to store phase coherence, it relies on collective effects in an atomic medium to store coherence. Such a laser uses repumped Dicke superradiance (or superfluorescence) to sustain emission of light that can have a substantially narrower linewidth than a conventional laser. See also * Dicke model * Superradiant phase transition In quantum optics, a superradiant phase transition is a phase transition that occurs in a collection of fluorescent emitters (such as atoms), between a state containing few electromagnetic excitations (as in the electromagnetic vacuum) and a su ... References Laser types {{optics-stub ...
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Nitrogen Laser
A nitrogen laser is a gas laser operating in the ultraviolet rangeC. S. Willett, ''Introduction to Gas Lasers: Population Inversion Mechanisms'' (Pergamon, New York,1974). (typically 337.1 nm) using molecular nitrogen as its gain medium, pumped by an electrical discharge. The wall-plug efficiency of the nitrogen laser is low, typically 0.1% or less, though nitrogen lasers with efficiency of up to 3% have been reported in the literature. The wall-plug efficiency is the product of the following three efficiencies: * electrical: TEA laser * gain medium: This is the same for all nitrogen lasers and thus has to be at least 3% ** inversion by electron impact is 10 to 1 due to Franck–Condon principle ** energy lost in the lower laser level: 40% * optical: More stimulated emission than spontaneous emission Gain medium The gain medium is nitrogen molecules in the gas phase. The nitrogen laser is a three-level laser. In contrast to more typical four-level lasers, the upper las ...
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Infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around 1  millimeter (300  GHz) to the nominal red edge of the visible spectrum, around 700  nanometers (430  THz). Longer IR wavelengths (30 μm-100 μm) are sometimes included as part of the terahertz radiation range. Almost all black-body radiation from objects near room temperature is at infrared wavelengths. As a form of electromagnetic radiation, IR propagates energy and momentum, exerts radiation pressure, and has properties corresponding to both those of a wave and of a particle, the photon. It was long known that fires emit invisible heat; in 1681 the pioneering experimenter Edme Mariotte showed that glass, though transparent to sunlight, obstructed radiant heat. In 1800 the astronomer Sir William Herschel discove ...
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Ion Laser
An ion laser is a gas laser that uses an ionized gas as its lasing medium. Like other gas lasers, ion lasers feature a sealed cavity containing the laser medium and mirrors forming a Fabry–Pérot resonator. Unlike helium–neon lasers, the energy level transitions that contribute to laser action come from ions. Because of the large amount of energy required to excite the ionic transitions used in ion lasers, the required current is much greater, and as a result all but the smallest ion lasers are water-cooled. A small air-cooled ion laser might produce, for example, 130 milliwatts of output light with a tube current of about 10 amperes and a voltage of 105 volts. Since one ampere times one volt is one watt, this is an electrical power input of about one kilowatt. Subtracting the (desirable) light output of 130 mW from power input, this leaves the large amount of waste heat of nearly one kW. This has to be dissipated by the cooling system. In other words, the power efficiency ...
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