diffraction grating

American  

noun

Physics.

1. a band of equidistant, parallel lines, usually more than 5000 per inch (2000 per centimeter), ruled on a glass or polished metal surface for diffracting light to produce optical spectra.

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diffraction grating British  

noun

1. a glass plate or a mirror with a large number of equidistant parallel lines or grooves on its surface. It causes diffraction of transmitted or reflected light, ultraviolet radiation, or X-rays

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diffraction grating Scientific  

1. A polished surface, often of glass or metal, having many fine parallel stripes or slits through which radiation such as light is passed and projected onto a screen or other detection device. The interference patterns cast by the diffraction grating on the screen or detector can be analyzed to determine the frequency of the radiation.

2. See also interferometer

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Etymology

Origin of diffraction grating

First recorded in 1865–70

Example Sentences

Light from the galaxy passes through a prism or reflects off a diffraction grating in a telescope, which captures the intensity of light from blue to red.

From Salon • Feb. 14, 2025

"However, deflecting light by diffraction grating allows much more precise control of the laser light compared to deflection in the Earth's atmosphere," says Schrödel.

From Science Daily • Oct. 3, 2023

A diffraction grating can be manufactured by scratching glass with a sharp tool in a number of precisely positioned parallel lines, with the untouched regions acting like slits.

From Textbooks • Aug. 12, 2015

The yellow light from a sodium vapor lamp seems to be of pure wavelength, but it produces two first-order maxima at 36.093º and 36.129º when projected on a 10,000 line per centimeter diffraction grating.

From Textbooks • Aug. 12, 2015

The first real clue to the nature of Venus came from work with a prism made of glass or a flat surface, called a diffraction grating, covered with fine, regularly spaced, ruled lines.

From "Cosmos" by Carl Sagan