List of types of interferometers

An interferometer is a technical device, which serves to interferometry. It is used for the detection of interference ( superposition of waves) for precision measurements. Fields of application are the length measurement, refractive index measurement, angle measurement, and spectroscopy. In addition to interferometry with light waves, there are also atom interferometers.


There are various types of interferometers, wherein the functioning is substantially the same. At least two light beams from mirrors or semitransparent plates ( so-called beam splitters ) performed by using separate optical paths, reflected at the end of the path by additional mirrors and recombined at the end. Result is an interference pattern (interference stripes or rings ), which was described by the light beam as a pattern. This pattern is determined by the difference of the optical paths that have the individual beams back down to the union.


  • Bath interferometer
  • Mach- Zehnder interferometer and its precursor Jamin interferometer
  • Michelson interferometer Twyman- Green interferometer


  • Fabry-Perot interferometer
  • Fizeau interferometer


Interferometers are used in physics, astronomy and metrology in various versions for a variety of purposes.

One of the most famous experiments in the history of the Michelson -Morley experiment proved using a Michelson interferometer that the speed of light in any frame of reference is the same. The result of this experiment gave the ether theory to falter and was also one of the basic assumptions of the later established by Albert Einstein special relativity. Following the same principle, one tries to prove a modern Michelson interferometer in the Geo -600 project gravitational waves.

Today interferometer in astronomy at all wavelength ranges are used to improve the resolution. With interferometers from radio telescopes can be reached because of the much higher base length of an approximately 500 times higher angular resolution than in the optical range. The " Very Large Telescope" provides means of interference high-resolution images in the visible spectral range. ( See also: Astronomical Interferometry )

Other applications find interferometer as a laser Doppler vibrometer, a measuring instrument for measuring vibrations. Laser interferometer for distance measurement using the interference and white light interferometer and phase-shifting interferometer as instruments for shape measurement of workpieces. Another field of application is the FTIR spectrometer, an instrument for chemical analysis of materials. For the investigation of interfacial processes, the Kapillarwellenspektroskopie used.