interferometer Interferometry is a technique which uses the ''interference'' of superimposed waves to extract information. Interferometry typically uses electromagnetic waves and is an important investigative technique in the fields of astronomy, fiber op ...

is a device for extracting information from the superposition of multiple waves.

Field and linear interferometers

Air-wedge shearing interferometer The air-wedge shearing interferometer is probably the simplest type of interferometer designed to visualize the disturbance of the wavefront after propagation through a test object. This interferometer is based on utilizing a thin wedged air-gap be ...

Astronomical interferometer An astronomical interferometer or telescope array is a set of separate telescopes, mirror segments, or radio telescope antenna (radio), antennas that work together as a single telescope to provide higher resolution images of astronomical objects ...

Michelson stellar interferometer The Michelson stellar interferometer is one of the earliest astronomical interferometers built and used. The interferometer was proposed by Albert A. Michelson in 1890, following a suggestion by Hippolyte Fizeau. The first such interferometer b ...

* Classical interference microscopy *

Bath interferometer (common path) Karl-Ludwig Bath patented 5 designs of common path interferometers in 1973. Bath interferometers can be used to test telescope mirrors of any size. A Common path interferometer has the test and reference beams traveling over effectively the ...

* Cyclic interferometer * Diffraction-grating interferometer (white light) * Double-slit interferometer *

Dual-polarization interferometry Dual-polarization interferometry (DPI) is an analytical technique that probes molecular layers adsorbed to the surface of a Waveguide (optics), waveguide using the evanescent wave of a laser beam. It is used to measure the conformational change ...

Fabry–Pérot interferometer In optics, a Fabry–Pérot interferometer (FPI) or etalon is an optical cavity made from two parallel reflecting surfaces (i.e.: thin mirrors). Optical waves can pass through the optical cavity only when they are in resonance with it. It is ...

Fizeau interferometer A Fizeau interferometerLawson, Peter R. "Principles of Long Baseline Stellar Interferometry." Course notes from the 1999 Michelson Summer School, held August 15–19, 1999. Edited by Peter R. Lawson. Published by National Aeronautics and Space Admi ...

* Fourier-transform interferometer *

Fresnel interferometer Augustin-Jean Fresnel (10 May 1788 – 14 July 1827) was a French civil engineer and physicist whose research in optics led to the almost unanimous acceptance of the wave theory of light, excluding any remnant of Isaac Newton, Newton's co ...

(e.g. Fresnel biprism,

Fresnel mirror In atomic physics, a ridged mirror (or ridged atomic mirror, or Fresnel diffraction mirror) is a kind of atomic mirror, designed for the specular reflection of neutral particles ( atoms) coming at a grazing incidence angle. In order to reduce the ...

Lloyd's mirror Lloyd's mirror is an optics experiment that was first described in 1834 by Humphrey Lloyd in the ''Transactions of the Royal Irish Academy''. Its original goal was to provide further evidence for the wave nature of light, beyond those provided by ...

) *

Fringes of Equal Chromatic Order Fringe may refer to: Arts * Edinburgh Festival Fringe, the world's largest arts festival, known as "the Fringe" * Adelaide Fringe, the world's second-largest annual arts festival * Fringe theatre, a name for alternative theatre * The Fringe, the ...

interferometer (FECO) * Gabor hologram *

Gires–Tournois etalon In optics, a Gires–Tournois etalon is a transparent plate with two reflecting surfaces, one of which has very high reflectivity, ideally unity. Due to multiple-beam interference, light incident on a Gires–Tournois etalon is (almost) completely ...

* Heterodyne interferometer (see

heterodyne A heterodyne is a signal frequency that is created by combining or mixing two other frequencies using a signal processing technique called ''heterodyning'', which was invented by Canadian inventor-engineer Reginald Fessenden. Heterodyning is u ...

) * Holographic interferometer *

Jamin interferometer The Jamin interferometer is a type of interferometer, related to the Mach–Zehnder interferometer. It was developed in 1856 by the French physicist Jules Jamin. The interferometer consists of two mirrors, made of the thickest glass possible. T ...

Laser Doppler vibrometer A laser Doppler vibrometer (LDV) is a scientific instrument that is used to make non-contact vibration measurements of a surface. The laser beam from the LDV is directed at the surface of interest, and the vibration amplitude and frequency are extr ...

Linnik interferometer A Linnik interferometer is a two-beam interferometer used in microscopy and surface contour measurements or topography. The basic configuration is the same as a Michelson interferometer. What distinguishes the Linnik configuration is the use of ...

(microscopy) * LUPI variant of Michelson *

Lummer–Gehrcke interferometer The Lummer–Gehrcke interferometer or Lummer–Gehrcke plate is a multiple-beam interferometer similar to the Fabry–Pérot etalon, but using light at a steep angle of incidence. The interferometer consists of a long plate of glass or quartz, w ...

Mach–Zehnder interferometer The Mach–Zehnder interferometer is a device used to determine the relative phase shift variations between two collimated beams derived by splitting light from a single source. The interferometer has been used, among other things, to measure pha ...

Martin–Puplett interferometer A Martin–Puplett interferometer measures the difference between the powers of two input beams. It is similar to a Michelson interferometer The Michelson interferometer is a common configuration for optical interferometry and was invented ...

Michelson interferometer The Michelson interferometer is a common configuration for optical interferometry and was invented by the 19/20th-century American physicist Albert Abraham Michelson. Using a beam splitter, a light source is split into two arms. Each of those li ...

Mirau interferometer A Mirau interferometer works on the same basic principle as a Michelson interferometer. The difference between the two is in the physical location of the reference arm. The reference arm of a Mirau interferometer is located within a microscope obj ...

(also known as a Mirau objective) (microscopy) * Moiré interferometer (see

moiré pattern In mathematics, physics, and art, moiré patterns ( , , ) or moiré fringes are large-scale interference patterns that can be produced when an opaque ruled pattern with transparent gaps is overlaid on another similar pattern. For the moiré ...

) * Multi-beam interferometer (

microscopy Microscopy is the technical field of using microscopes to view objects and areas of objects that cannot be seen with the naked eye (objects that are not within the resolution range of the normal eye). There are three well-known branches of micr ...

) * Near-field interferometer *

Newton interferometer Newton most commonly refers to: * Isaac Newton (1642–1726/1727), English scientist * Newton (unit), SI unit of force named after Isaac Newton Newton may also refer to: Arts and entertainment * Newton (film), ''Newton'' (film), a 2017 Indian f ...

(see

Newton's rings Newton's rings is a phenomenon in which an interference pattern is created by the reflection of light between two surfaces, typically a spherical surface and an adjacent touching flat surface. It is named after Isaac Newton, who investigated the ...

) *

Nomarski interferometer Georges (Jerzy) Nomarski (January 6, 1919 – 1997) was a Polish physicist and optics theoretician. Creator of differential interference contrast (DIC) microscopy, the method is widely used to study live biological specimens and unstained tissues an ...

* Nonlinear

/ Step-phase

N-slit interferometer The ''N''-slit interferometer is an extension of the double-slit experiment, double-slit interferometer also known as Young's double-slit interferometer. One of the first known uses of ''N''-slit arrays in optics was illustrated by Isaac Newton, Ne ...

* Phase-shifting interferometer * Planar lightwave circuit interferometer (PLC) *

Photon Doppler velocimeter interferometer Laser Doppler velocimetry, also known as laser Doppler anemometry, is the technique of using the Doppler effect, Doppler shift in a laser beam to measure the velocity in transparent or semi-transparent fluid flows or the linear or vibratory motion ...

(PDV) * Polarization interferometer (see also Babinet–Soleil compensator) *

Point diffraction interferometer A point diffraction interferometer (PDI) is a type of common-path interferometer. Unlike an amplitude-splitting interferometer, such as a Michelson interferometer, which separates out an unaberrated beam and interferes this with the test beam, a ...

Rayleigh interferometer In optics, a Rayleigh interferometer is a type of interferometer which employs two beams of light from a single source. The two beams are recombined after traversing two optical paths, and the interference pattern after recombination allows the ...

Sagnac interferometer The Sagnac effect, also called Sagnac interference, named after French physicist Georges Sagnac, is a phenomenon encountered in interferometry that is elicited by rotation. The Sagnac effect manifests itself in a setup called a ring interferometer ...

* Schlieren interferometer (phase-shifting) *

Shearing interferometer The shearing interferometer is an extremely simple means to observe interference and to use this phenomenon to test the collimation of light beams, especially from laser A laser is a device that emits light through a process of optical ampli ...

(lateral and radial) *

Twyman–Green interferometer A Twyman–Green interferometer is a variant of the Michelson interferometer principally used to test optical components. It was introduced in 1916 by Frank Twyman and Arthur Green. Fig. 1 illustrates a Twyman–Green interferometer set up to ...

* Talbot–Lau interferometer * Watson interferometer (microscopy) * White-light interferometer (see also

Optical coherence tomography Optical coherence tomography (OCT) is an imaging technique that uses low-coherence light to capture micrometer-resolution, two- and three-dimensional images from within optical scattering media (e.g., biological tissue). It is used for medical ...

) * White-light scatterplate interferometer (white-light) (microscopy) *

Young's double-slit interferometer Young's interference experiment, also called Young's double-slit interferometer, was the original version of the modern double-slit experiment, performed at the beginning of the nineteenth century by Thomas Young (scientist), Thomas Young. This ex ...

Zernike phase-contrast microscopy __NOTOC__ Phase-contrast microscopy (PCM) is an optical microscopy technique that converts phase shifts in light passing through a transparent specimen to brightness changes in the image. Phase shifts themselves are invisible, but become visible ...

Intensity and nonlinear interferometers

intensity interferometer An intensity interferometer is the name given to devices that use the Hanbury Brown and Twiss effect. In astronomy, the most common use of such an astronomical interferometer is to determine the apparent angular diameter of a radio source or star. ...

* intensity

optical correlator An optical correlator is an optical computer for comparing two signals by utilising the Fourier transforming properties of a lens. It is commonly used in optics for target tracking and identification. Introduction The correlator has an input si ...

frequency-resolved optical gating Frequency-resolved optical gating (FROG) is a general method for measuring the spectral phase of ultrashort laser pulses, which range from sub femtosecond to about a nanosecond in length. Invented in 1991 by Rick Trebino and Daniel J. Kane, FROG wa ...

(FROG) *

Spectral phase interferometry for direct electric-field reconstruction In ultrafast optics, spectral phase interferometry for direct electric-field reconstruction (SPIDER) is an ultrashort pulse measurement technique originally developed by Chris Iaconis and Ian Walmsley. The basics SPIDER is an interferometric ultr ...

(SPIDER)

Quantum optics interferometers

* Hong–Ou–Mandel interferometer (HOM) (see Hong–Ou–Mandel effect) * Franson interferometer * Hanbury–Brown Twiss interferometer *

Polariton Interferometer In physics, polaritons are quasiparticles resulting from strong coupling of electromagnetic waves with an electric or magnetic dipole-carrying excitation. They are an expression of the common quantum phenomenon known as level repulsion, also ...

Interferometers outside optics

Acoustic interferometer An acoustic interferometer is an instrument, using interferometry, for measuring the physical characteristics of sound waves in a gas or liquid. It may be used to measure velocity, wavelength, absorption, or impedance. A vibrating crystal ...

Atom interferometer An atom interferometer is an interferometer which uses the Wave–particle duality, wave character of atoms. Similar to optical interferometers, atom interferometers measure the difference in phase between atomic matter waves along different paths. ...

Neutron interferometer In physics, a neutron interferometer is an interferometer capable of diffracting neutrons, allowing the wave-like nature of neutrons, and other related phenomena, to be explored. Interferometry Interferometry inherently depends on the wave natu ...

Ramsey interferometer Ramsey may refer to: Geography British Isles * Ramsey, Cambridgeshire, a small market town in England * Ramsey, Essex, a village near Harwich, England ** Ramsey and Parkeston, a civil parish formerly called just "Ramsey" * Ramsey, Isle of Man, th ...

* Mini grail interferometer *

Aharonov–Bohm effect The Aharonov–Bohm effect, sometimes called the Ehrenberg–Siday–Aharonov–Bohm effect, is a quantum mechanical phenomenon in which an electrically charged particle is affected by an electromagnetic potential (φ, A), despite being confine ...

Interferometric synthetic-aperture radar Interferometric synthetic aperture radar, abbreviated InSAR (or deprecated IfSAR), is a radar technique used in geodesy and remote sensing. This geodetic method uses two or more synthetic aperture radar (SAR) images to generate maps of surface defor ...

(a radar-based 3-d surface mapping) * Superconducting quantum interference devices (SQUIDs) * White–Juday warp-field interferometer

Field and linear interferometers

Intensity and nonlinear interferometers

Quantum optics interferometers

Interferometers outside optics

See also