interferometer

American  

[in-ter-fuh-rom-i-ter] / ˌɪn tər fəˈrɒm ɪ tər /

noun

1. Optics. a device that separates a beam of light into two ray beams, usually by means of reflection, and that brings the rays together to produce interference, used to measure wavelength, index of refraction, and astronomical distances.

2. Astronomy. an instrument for measuring the angular separation of double stars or the diameter of giant stars by means of the interference phenomena of light emitted by these stars.

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interferometer British  

/ ˌɪntəˌfɛrəˈmɛtrɪk, ˌɪntəfəˈrɒmɪtə /

noun

1. physics any acoustic, optical, or microwave instrument that uses interference patterns or fringes to make accurate measurements of wavelength, wave velocity, distance, etc

2. astronomy a radio or optical array consisting of two or more telescopes separated by a known distance and connected so that the radiation from a source in space undergoes interference, enabling the source to be imaged or the position of the source to be accurately determined

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interferometer Scientific  

/ ĭn′tər-fə-rŏm′ĭ-tər /

1. Any of several optical, acoustic, or radio frequency instruments that use interference phenomena between a reference wave and an experimental wave or between two parts of an experimental wave to determine wavelengths and wave velocities, measure very small distances and thicknesses, and calculate indices of refraction.

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Other Word Forms

• interferometric adjective
• interferometrically adverb
• interferometry noun

Etymology

Origin of interferometer

First recorded in 1895–1900; interfere + -o- + -meter

Example Sentences

However, producing images with an interferometer like the ones we are used to obtaining from single telescopes is not straightforward and very time-consuming.

From Science Daily • Jan. 8, 2024

Other work to improve detection sensitivity has included changing out mirrors that had tiny imperfections in their coating and adding baffles to reduce excess light in the interferometer.

From Seattle Times • May 29, 2023

Each of those detectors is an L-shaped optical device called an interferometer with arms 4 kilometers long that make ultraprecise measurements of space in perpendicular directions.

From Science Magazine • Apr. 19, 2023

Aperture Masking: A perforated metal plate blocks some of the light entering the telescope, allowing it to simulate an interferometer, which combines data from multiple telescopes to achieve higher resolution than a single lens.

From Scientific American • Dec. 1, 2022

He took a personal interest in her, because some of his friends were collaborating in experiments to measure her diameter by Michelson’s interferometer.

From "Cheaper by the Dozen" by Frank B. Gilbreth Jr. and Ernestine Gilbreth Carey