 | This article needs additional citations for verification .(May 2007) |
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.
| Laser gain medium and type | Operation wavelength(s) | Pump source | Applications and notes |
|---|---|---|---|
| Helium–neon laser | 632.8 nm (543.5 nm, 593.9 nm, 611.8 nm, 1.1523 μm, 1.52 μm, 3.3913 μm) | Electrical discharge | Interferometry, holography, spectroscopy, barcode scanning, alignment, optical demonstrations. |
| Argon laser | 454.6 nm, 488.0 nm, 514.5 nm (351 nm, 363.8, 457.9 nm, 465.8 nm, 476.5 nm, 472.7 nm, 528.7 nm, also frequency doubled to provide 244 nm, 227 nm) | Electrical discharge | Retinal phototherapy (for diabetes), lithography, confocal microscopy, spectroscopy pumping other lasers. |
| Krypton laser | 416 nm, 530.9 nm, 568.2 nm, 647.1 nm, 676.4 nm, 752.5 nm, 799.3 nm | Electrical discharge | Scientific research, mixed with argon to create "white-light" lasers, light shows. |
| Xenon ion laser | Many lines throughout visible spectrum extending into the UV and IR | Electrical discharge | Scientific research. |
| Nitrogen laser | 337.1 nm | Electrical discharge | Pumping of dye lasers, measuring air pollution, scientific research. Nitrogen lasers can operate superradiantly (without a resonator cavity). Amateur laser construction. See TEA laser. |
| Carbon dioxide laser | 10.6 μm, (9.4 μm) | Transverse (high-power) or longitudinal (low-power) electrical discharge | Material processing (laser cutting, laser beam welding, etc.), surgery, dental laser, military lasers. |
| Carbon monoxide laser | 2.6 to 4 μm, 4.8 to 8.3 μm | Electrical discharge | Material processing (engraving, welding, etc.), photoacoustic spectroscopy. |
| Excimer laser | 157 nm (F2), 193.3 nm (ArF), 248 nm (KrF), 308 nm (XeCl), 351 nm (XeF) | Excimer recombination via electrical discharge | Ultraviolet lithography for semiconductor manufacturing, laser surgery, LASIK, scientific research. |
Used as directed-energy weapons.
| Laser gain medium and type | Operation wavelength(s) | Pump source | Applications and notes |
|---|---|---|---|
| Hydrogen fluoride laser | 2.7 to 2.9 μm for hydrogen fluoride (<80% atmospheric transmittance) | Chemical reaction in a burning jet of ethylene and nitrogen trifluoride (NF3) | Used in research for laser weaponry, operated in continuous-wave mode, can have power in the megawatt range. |
| Deuterium fluoride laser | ~3800 nm (3.6 to 4.2 μm) (~90% atm. transmittance) | chemical reaction | US military laser prototypes. |
| COIL (chemical oxygen – iodine laser) | 1.315 μm (<70% atmospheric transmittance) | Chemical reaction in a jet of singlet delta oxygen and iodine | Military lasers, scientific and materials research. Can operate in continuous wave mode, with power in the megawatt range. |
| Agil (All gas-phase iodine laser) | 1.315 μm (<70% atmospheric transmittance) | Chemical reaction of chlorine atoms with gaseous hydrazoic acid, resulting in excited molecules of nitrogen chloride, which then pass their energy to the iodine atoms. | Scientific, weaponry, aerospace. |
| Laser gain medium and type | Operation wavelength(s) | Pump source | Applications and notes |
|---|---|---|---|
| Dye lasers | 390-435 nm (stilbene), 460-515 nm (coumarin 102), 570-640 nm (rhodamine 6G), many others | Other laser, flashlamp | Research, laser medicine, [2] spectroscopy, birthmark removal, isotope separation. The tuning range of the laser depends on which dye is used. |
| Laser gain medium and type | Operation wavelength(s) | Pump source | Applications and notes |
|---|---|---|---|
| Helium – cadmium (HeCd) metal-vapor laser | 325 nm, 441.563 nm | Electrical discharge in metal vapor mixed with helium buffer gas. | Printing and typesetting applications, fluorescence excitation examination (i.e. in U.S. paper currency printing), scientific research. |
| Helium – mercury (HeHg) metal-vapor laser | 567 nm, 615 nm | (Rare) Scientific research, amateur laser construction. | |
| Helium – selenium (HeSe) metal-vapor laser | up to 24 wavelengths between red and UV | (Rare) Scientific research, amateur laser construction. | |
| Helium – silver (HeAg) metal-vapor laser [3] | 224.3 nm | Scientific research | |
| Strontium vapor laser | 430.5 nm | Scientific research | |
| Neon – copper (NeCu) metal-vapor laser [3] | 248.6 nm | Electrical discharge in metal vapor mixed with neon buffer gas. | Scientific research: Raman and fluorescence spectroscopy [4] [5] |
| Copper vapor laser | 510.6 nm, 578.2 nm | Electrical discharge | Dermatological uses, high speed photography, pump for dye lasers. |
| Gold vapor laser | 627 nm | (Rare) Dermatological uses, photodynamic therapy. [6] | |
| Manganese (Mn/MnCl2) vapor laser | 534.1 nm | Pulsed electric discharge | [ citation needed ] |
| Laser gain medium and type | Operation wavelength(s) | Pump source | Applications and notes |
|---|---|---|---|
| Ruby laser | 694.3 nm | Flashlamp | Holography, tattoo removal. The first laser, invented by Theodore Maiman in May 1960. |
| Nd:YAG laser | 1.064 μm, (1.32 μm) | Flashlamp, laser diode | Material processing, rangefinding, laser target designation, surgery, tattoo removal, hair removal, research, pumping other lasers (combined with frequency doubling to produce a green 532 nm beam). One of the most common high-power lasers. Usually pulsed (down to fractions of a nanosecond), dental laser |
| Nd:YAP laser (yttrium aluminium perovskite) | 1.0646 μm [7] | Flashlamp, laser diode | Surgery, tattoo removal, hair removal, research, pumping other lasers (combined with frequency doubling to produce a green 532 nm beam) |
| Nd:Cr:YAG laser | 1.064 μm, (1.32 μm) | solar radiation | Experimental production of nanopowders. [8] |
| Er:YAG laser | 2.94 μm | Flashlamp, laser diode | Periodontal scaling, dental laser, skin resurfacing |
| Neodymium YLF (Nd:YLF) solid-state laser | 1.047 and 1.053 μm | Flashlamp, laser diode | Mostly used for pulsed pumping of certain types of pulsed Ti:sapphire lasers, combined with frequency doubling. |
| Neodymium-doped yttrium orthovanadate (Nd:YVO4) laser | 1.064 μm | laser diode | Mostly used for continuous pumping of mode-locked Ti:sapphire or dye lasers, in combination with frequency doubling. Also used pulsed for marking and micromachining. A frequency doubled nd:YVO4 laser is also the normal way of making a green laser pointer. |
| Neodymium-doped yttrium calcium oxoborate Nd:Y Ca 4 O(BO3)3 or simply Nd:YCOB | ~1.060 μm (~530 nm at second harmonic) | laser diode | Nd:YCOB is a so-called "self-frequency doubling" or SFD laser material which is both capable of lasing and which has nonlinear characteristics suitable for second harmonic generation. Such materials have the potential to simplify the design of high brightness green lasers. |
| Neodymium glass (Nd:Glass) laser | ~1.062 μm (silicate glasses), ~1.054 μm (phosphate glasses) | Flashlamp, laser diode | Used in extremely high-power (terawatt scale), high-energy (megajoules) multiple beam systems for inertial confinement fusion. Nd:Glass lasers are usually frequency tripled to the third harmonic at 351 nm in laser fusion devices. |
| Titanium sapphire (Ti:sapphire) laser | 650-1100 nm | Other laser | Spectroscopy, LIDAR, research. This material is often used in highly-tunable mode-locked infrared lasers to produce ultrashort pulses and in amplifier lasers to produce ultrashort and ultra-intense pulses. |
| Thulium YAG (Tm:YAG) laser | 2.0 μm | Laser diode | LIDAR. |
| Ytterbium YAG (Yb:YAG) laser | 1.03 μm | Laser diode, flashlamp | Laser cooling, materials processing, ultrashort pulse research, multiphoton microscopy, LIDAR. |
| Ytterbium:2O3 (glass or ceramics) laser | 1.03 μm | Laser diode | Ultrashort pulse research, [9] |
| Ytterbium-doped glass laser (rod, plate/chip, and fiber) | 1. μm | Laser diode | Fiber version is capable of producing several-kilowatt continuous power, having ~70-80% optical-to-optical and ~25% electrical-to-optical efficiency. Material processing: cutting, welding, marking; nonlinear fiber optics: broadband fiber-nonlinearity based sources, pump for fiber Raman lasers; distributed Raman amplification pump for telecommunications. |
| Holmium YAG (Ho:YAG) laser | 2.1 μm | Flashlamp, laser diode | Tissue ablation, kidney stone removal, dentistry. |
| Chromium ZnSe (Cr:ZnSe) laser | 2.2 - 2.8 μm | Other laser (Tm fiber) | MWIR laser radar, countermeasure against heat-seeking missiles etc. |
| Cerium-doped lithium strontium (or calcium) aluminum fluoride (Ce:LiSAF, Ce:LiCAF) | ~280 to 316 nm | Frequency quadrupled Nd:YAG laser pumped, excimer laser pumped, copper vapor laser pumped. | Remote atmospheric sensing, LIDAR, optics research. |
| Promethium-147-doped phosphate glass (147Pm+3:Glass) solid-state laser | 933 nm, 1098 nm | ?? | Laser material is radioactive. Once demonstrated in use at LLNL in 1987, room temperature 4 level lasing in 147Pm doped into a lead-indium-phosphate glass étalon. |
| Chromium-doped chrysoberyl (alexandrite) laser | Typically tuned in the range of 700 to 820 nm | Flashlamp, laser diode, mercury arc (for CW mode operation) | Dermatological uses, LIDAR, laser machining. |
| Erbium –ytterbium and Erbium-doped glass lasers | 1.53–1.56 μm | Flashlamp, laser diode | Erbium-ytterbium and erbium-doped glass lasers are made in rod, plate/chip, and optical fiber form. Common uses for Er:glass lasers include rangefinding and skin resurfacing. Erbium doped fibers are commonly used as optical amplifiers for telecommunications. |
| Trivalent uranium-doped calcium fluoride (U:CaF2) solid-state laser | 2.5 μm | Flashlamp | First 4-level solid state laser (November 1960) developed by Peter Sorokin and Mirek Stevenson at IBM research labs, second laser invented overall (after Maiman's ruby laser), liquid helium cooled, unused today. |
| Divalent samarium-doped calcium fluoride (Sm:CaF2) laser | 708.5 nm | Flashlamp | Also invented by Peter Sorokin and Mirek Stevenson at IBM research labs, early 1961. Liquid helium-cooled, unused today. |
| F-center laser | 2.3-3.3 μm | Ion laser | Spectroscopy |
| Optically pumped semiconductor laser | 920 nm-1.35 μm | Laser diode | Projection, life sciences, forensic analysis, spectroscopy, eye surgery, laser light shows. The lasing medium is a semiconductor chip. Frequency doubling or tripling is typically done to produce visible or ultraviolet radiation. Power levels of several watts are possible. Beam quality can be extremely high- often rivaling that of an ion laser. |
| Laser gain medium and type | Operation wavelength(s) | Pump source | Applications and notes |
|---|---|---|---|
| Semiconductor laser diode (general information) | 0.4-20 μm, depending on active region material. | Electrical current | Telecommunications, holography, printing, weapons, machining, welding, pump sources for other lasers, high-beam headlights for automobiles. [10] |
| GaN | 0.4 μm | Optical discs. 405 nm is used in Blu-ray Discs reading/recording. | |
| InGaN | 0.4 - 0.5 μm | Home projector, primary light source for some recent small projectors | |
| AlGaInP, AlGaAs | 0.63-0.9 μm | Optical discs, laser pointers, data communications. 780 nm compact disc, 650 nm general DVD player and 635 nm DVD for Authoring recorder laser are the most common lasers type in the world. Solid-state laser pumping, machining, medical. | |
| InGaAsP | 1.0-2.1 μm | Telecommunications, solid-state laser pumping, machining, medical.. | |
| lead salt | 3-20 μm | ||
| Vertical-cavity surface-emitting laser (VCSEL) | 850–1500 nm, depending on material | Telecommunications | |
| Quantum cascade laser | Mid-infrared to far-infrared. | Research, Future applications may include collision-avoidance radar, industrial-process control and medical diagnostics such as breath analyzers. | |
| Quantum dot laser | wide range. | Medicine (laser scalpel, optical coherence tomography), display technologies (projection, laser TV), spectroscopy and telecommunications. | |
| Quantum well laser | 0.4-20 μm, depending on active region material. | Telecommunications | |
| Hybrid silicon laser | Mid-infrared | Low cost silicon integrated optical communications | |
| Laser gain medium and type | Operation wavelength(s) | Pump source | Applications and notes |
|---|---|---|---|
| Free-electron laser | A broad wavelength range (0.1 nm - several mm); a single FEL may be tunable over a wavelength range | Relativistic electron beam | Atmospheric research, material science, medical applications. |
| CO₂ gas dynamic laser | Several lines around 10.5 μm; other frequencies may be possible with different gas mixtures | Spin state population inversion in carbon dioxide molecules caused by supersonic adiabatic expansion of mixture of nitrogen and carbon dioxide | Military applications; can operate in CW mode at several megawatts optical power. Manufacturing and Heavy Industry. |
| "Nickel-like" samarium laser [11] | X-rays at 7.3 nm wavelength | Lasing in ultra-hot samarium plasma formed by double pulse terawatt scale irradiation fluences. | Sub–10 nm X-ray laser, possible applications in high-resolution microscopy and holography. |
| Raman lasers, use inelastic stimulated Raman scattering in a nonlinear media, mostly fiber, for amplification | 1-2 μm for fiber version | Other laser, mostly Yb-glass fiber lasers | Complete 1-2 μm wavelength coverage; distributed optical signal amplification for telecommunications; optical solitons generation and amplification |
| Nuclear pumped laser | See gas lasers, soft x-ray | Nuclear fission: reactor, nuclear bomb | Research, weapons program. |
| Polariton laser | Near infrared | optically and electrically pumped [12] | spin switches and terahertz lasers [13] |
| Plasmonic laser | Near infrared and ultraviolet | optically pumped [14] | Nanoscale lithography, fabrication of ultra-fast photonic nano circuits, single-molecule biochemical sensing, and microscopy |
| Phonon laser | microwave to Far-infrared | electrically pumped | Investigation of terahertz-frequency ultrasound and optoelectronics |
| Gamma-ray laser | Gamma rays | Unknown | Hypothetical |
{{cite journal}}: CS1 maint: multiple names: authors list (link)| Types of lasers | |
|---|---|
| Laser physics | |
| Laser optics | |
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 anacronym that originated as an acronym for light amplification by stimulated emission of radiation. The first laser was built in 1960 by Theodore Maiman at Hughes Research Laboratories, based on theoretical work by Charles H. Townes and Arthur Leonard Schawlow.
Microscopy is the technical field of using microscopes to view objects and areas of objects that cannot be seen with the naked eye. There are three well-known branches of microscopy: optical, electron, and scanning probe microscopy, along with the emerging field of X-ray microscopy.
Raman spectroscopy is a spectroscopic technique typically used to determine vibrational modes of molecules, although rotational and other low-frequency modes of systems may also be observed. Raman spectroscopy is commonly used in chemistry to provide a structural fingerprint by which molecules can be identified.
A laser diode is a semiconductor device similar to a light-emitting diode in which a diode pumped directly with electrical current can create lasing conditions at the diode's junction.
A dye laser is a laser that uses an organic dye as the lasing medium, usually as a liquid solution. Compared to gases and most solid state lasing media, a dye can usually be used for a much wider range of wavelengths, often spanning 50 to 100 nanometers or more. The wide bandwidth makes them particularly suitable for tunable lasers and pulsed lasers. The dye rhodamine 6G, for example, can be tuned from 635 nm (orangish-red) to 560 nm (greenish-yellow), and produce pulses as short as 16 femtoseconds. Moreover, the dye can be replaced by another type in order to generate an even broader range of wavelengths with the same laser, from the near-infrared to the near-ultraviolet, although this usually requires replacing other optical components in the laser as well, such as dielectric mirrors or pump lasers.
The term biophotonics denotes a combination of biology and photonics, with photonics being the science and technology of generation, manipulation, and detection of photons, quantum units of light. Photonics is related to electronics and photons. Photons play a central role in information technologies, such as fiber optics, the way electrons do in electronics.
A free-electron laser (FEL) is a fourth generation light source producing extremely brilliant and short pulses of radiation. An FEL functions much as a laser but employs relativistic electrons as a gain medium instead of using stimulated emission from atomic or molecular excitations. In an FEL, a bunch of electrons passes through a magnetic structure called an undulator or wiggler to generate radiation, which re-interacts with the electrons to make them emit coherently, exponentially increasing its intensity.
A gas laser is a laser in which an electric current is discharged through a gas to produce coherent light. The gas laser was the first continuous-light laser and the first laser to operate on the principle of converting electrical energy to a laser light output. The first gas laser, the Helium–neon laser (HeNe), was co-invented by Iranian engineer and scientist Ali Javan and American physicist William R. Bennett, Jr., in 1960. It produced a coherent light beam in the infrared region of the spectrum at 1.15 micrometres.
A tunable laser is a laser whose wavelength of operation can be altered in a controlled manner. While all laser gain media allow small shifts in output wavelength, only a few types of lasers allow continuous tuning over a significant wavelength range.
Rhodamine 6G is a highly fluorescent rhodamine family dye. It is often used as a tracer dye within water to determine the rate and direction of flow and transport. Rhodamine dyes fluoresce and can thus be detected easily and inexpensively with instruments called fluorometers. Rhodamine dyes are used extensively in biotechnology applications such as fluorescence microscopy, flow cytometry, fluorescence correlation spectroscopy and ELISA.
Laser pumping is the act of energy transfer from an external source into the gain medium of a laser. The energy is absorbed in the medium, producing excited states in its atoms. When for a period of time the number of particles in one excited state exceeds the number of particles in the ground state or a less-excited state, population inversion is achieved. In this condition, the mechanism of stimulated emission can take place and the medium can act as a laser or an optical amplifier. The pump power must be higher than the lasing threshold of the laser.
A fiber laser is a laser in which the active gain medium is an optical fiber doped with rare-earth elements such as erbium, ytterbium, neodymium, dysprosium, praseodymium, thulium and holmium. They are related to doped fiber amplifiers, which provide light amplification without lasing.
Francisco Javier "Frank" Duarte is a laser physicist and author/editor of several books on tunable lasers.
A solid-state dye laser (SSDL) is a solid-state lasers in which the gain medium is a laser dye-doped organic matrix such as poly(methyl methacrylate) (PMMA), rather than a liquid solution of the dye. These lasers are also referred to as solid-state organic lasers and solid-state dye-doped polymer lasers.
Multiple-prism grating laser oscillators, or MPG laser oscillators, use multiple-prism beam expansion to illuminate a diffraction grating mounted either in Littrow configuration or grazing-incidence configuration. Originally, these narrow-linewidth tunable dispersive oscillators were introduced as multiple-prism Littrow (MPL) grating oscillators, or hybrid multiple-prism near-grazing-incidence (HMPGI) grating cavities, in organic dye lasers. However, these designs were quickly adopted for other types of lasers such as gas lasers, diode lasers, and more recently fiber lasers.
A polariton laser is a novel type of laser source that exploits the coherent nature of Bose condensates of exciton-polaritons in semiconductors to achieve ultra-low threshold lasing.
An organic laser is a laser which uses an organic material as the gain medium. The first organic laser was the liquid dye laser. These lasers use laser dye solutions as their gain media.
Stimulated Raman spectroscopy, also referred to as stimulated Raman scattering (SRS), is a form of spectroscopy employed in physics, chemistry, biology, and other fields. The basic mechanism resembles that of spontaneous Raman spectroscopy: a pump photon, of the angular frequency , which is scattered by a molecule has some small probability of inducing some vibrational transition, as opposed to inducing a simple Rayleigh transition. This makes the molecule emit a photon at a shifted frequency. However, SRS, as opposed to spontaneous Raman spectroscopy, is a third-order non-linear phenomenon involving a second photon—the Stokes photon of angular frequency —which stimulates a specific transition. When the difference in frequency between both photons resembles that of a specific vibrational transition the occurrence of this transition is resonantly enhanced. In SRS, the signal is equivalent to changes in the intensity of the pump and Stokes beams. The signals are typically rather low, of the order of a part in 10^5, thus calling for modulation-transfer techniques: one beam is modulated in amplitude, and the signal is detected on the other beam via a lock-in amplifier. Employing a pump laser beam of a constant frequency and a Stokes laser beam of a scanned frequency allows for unraveling the molecule's spectral fingerprint. This spectral fingerprint differs from those obtained by other spectroscopy methods, such as Rayleigh scattering, as the Raman transitions confer different exclusion rules than those that apply to Rayleigh transitions.
Coherent Raman scattering (CRS) microscopy is a multi-photon microscopy technique based on Raman-active vibrational modes of molecules. The two major techniques in CRS microscopy are stimulated Raman scattering (SRS) and coherent anti-Stokes Raman scattering (CARS). SRS and CARS were theoretically predicted and experimentally realized in the 1960s. In 1982 the first CARS microscope was demonstrated. In 1999, CARS microscopy using a collinear geometry and high numerical aperture objective were developed in Xiaoliang Sunney Xie's lab at Harvard University. This advancement made the technique more compatible with modern laser scanning microscopes. Since then, CRS's popularity in biomedical research started to grow. CRS is mainly used to image lipid, protein, and other bio-molecules in live or fixed cells or tissues without labeling or staining. CRS can also be used to image samples labeled with Raman tags, which can avoid interference from other molecules and normally allows for stronger CRS signals than would normally be obtained for common biomolecules. CRS also finds application in other fields, such as material science and environmental science.
A Pr:YLF laser (or Pr3+:LiYF4 laser) is a solid state laser that uses a praseodymium doped yttrium-lithium-fluoride crystal as its gain medium. The first Pr:YLF laser was built in 1977 and emitted pulses at 479 nm. Pr:YLF lasers can emit in many different wavelengths in the visible spectrum of light, making them potentially interesting for RGB applications and materials processing. Notable emission wavelengths are 479 nm, 523 nm, 607 nm and 640 nm.
