Interferometer

Interferometer: we measure with an accuracy of fractions of a wavelength

An interferometer is one of the most precise measuring instruments used in science and engineering. It can measure distances down to fractions of a wavelength of light and is used in a wide range of fields, including astronomy, optics, physics and metrology.

The main operating principle of an interferometer is the interference of light waves. In an interferometer, light waves traveling through different paths can cross and mutually enhance or cancel each other, creating an interference pattern. Measuring the phase difference between interfering waves allows the distance between light sources to be determined with high accuracy.

There are several types of interferometers, including Fabry-Perot, Michelson, Mach-Zehnder and Swann-Fermi. Each of them has its own specific features, but their operating principle is the same.

The use of interferometers is very wide. For example, a Michelson interferometer can measure the speed of stars, as well as determine the wavelengths of light and the refractive index of materials. Interferometers are also used to measure the length and width of objects in micro- and nanotechnology.

One of the most famous examples of interferometer applications is the Laser Interferometer for Gravitational Waves (LIGO), which was used to detect gravitational waves in 2015. This interferometer consists of two perpendicular beams of light flowing along 4 km of tubes, and can measure incredibly small changes in the length of these tubes caused by the passage of gravitational waves.

Thus, an interferometer is a unique and versatile device that has found wide application in science and technology. It allows you to measure the slightest changes in quantities with high accuracy and is an essential tool for many areas of science and technology.

An interferometer is a device designed to measure the wavelengths of light or to study the characteristics of wave processes using the phenomenon of interference, based on the superposition of two or more coherent (i.e., having the same oscillation phase) monochromatic electromagnetic waves. There are interferometers that measure the length and angular phase shift of radiation (for example, a slit interferometer) and interferograms, which are a combination of many interferograms obtained in different optical sections.