Watson interferometer

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The Watson interferometer is a vintage microscope accessory (for use only in reflected light microscopy) which was manufactured by the Watson Company in Great Britain. It is a variant of Michelson interferometer that can be installed on a conventional microscope. It consists of a beam splitter and varying the distance between the specimen surface and the image of the reference mirror creates interference fringes. For transmitted light investigations in biology, the C. Watson company produced the Smith/Baker system in the 1950s.

Michelson interferometer common configuration for optical interferometry invented by Albert Abraham Michelson

The Michelson interferometer is a common configuration for optical interferometry and was invented by Albert Abraham Michelson. Using a beam splitter, a light source is split into two arms. Each of those light beams is reflected back toward the beamsplitter which then combines their amplitudes using the superposition principle. The resulting interference pattern that is not directed back toward the source is typically directed to some type of photoelectric detector or camera. For different applications of the interferometer, the two light paths can be with different lengths or incorporate optical elements or even materials under test.

Beam splitter optical device that splits a beam of light in two, crucial part of most interferometers

A beam splitter is an optical device that splits a beam of light in two. It is the crucial part of most interferometers.

Classical interference microscopy, also called quantitative interference microscopy, uses two separate light beams with much greater lateral separation than that used in phase contrast microscopy or in differential interference microscopy (DIC).

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Fourier-transform spectroscopy is a measurement technique whereby spectra are collected based on measurements of the coherence of a radiative source, using time-domain or space-domain measurements of the electromagnetic radiation or other type of radiation. It can be applied to a variety of types of spectroscopy including optical spectroscopy, infrared spectroscopy, nuclear magnetic resonance (NMR) and magnetic resonance spectroscopic imaging (MRSI), mass spectrometry and electron spin resonance spectroscopy. There are several methods for measuring the temporal coherence of the light, including the continuous wave Michelson or Fourier-transform spectrometer and the pulsed Fourier-transform spectrograph.


Cathodoluminescence is an optical and electromagnetic phenomenon in which electrons impacting on a luminescent material such as a phosphor, cause the emission of photons which may have wavelengths in the visible spectrum. A familiar example is the generation of light by an electron beam scanning the phosphor-coated inner surface of the screen of a television that uses a cathode ray tube. Cathodoluminescence is the inverse of the photoelectric effect, in which electron emission is induced by irradiation with photons.

Interferometry measurement method using interference of waves

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Angular resolution or spatial resolution describes the ability of any image-forming device such as an optical or radio telescope, a microscope, a camera, or an eye, to distinguish small details of an object, thereby making it a major determinant of image resolution. In physics and geosciences, the term spatial resolution refers to the precision of a measurement with respect to space.

Mach–Zehnder interferometer interferometer

In physics, 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 phase shifts between the two beams caused by a sample or a change in length of one of the paths. The apparatus is named after the physicists Ludwig Mach and Ludwig Zehnder: Zehnder's proposal in an 1891 article was refined by Mach in an 1892 article.

Sagnac effect

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Neutron interferometer interferometer using neutron diffraction to make precise measurements

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Virgo interferometer gravitational waves detector

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Fourier-transform infrared spectroscopy

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Mirau interferometer

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The N-slit interferometer is an extension of the 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 Newton. In the first part of last century, Michelson described various cases of N-slit diffraction.

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White light interferometry

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