Scientists Say: Diffraction

When light hits an object, this is how it finds a way around

diffracted laser

This is a diffraction pattern made when a laser beam passes through a tiny circular hole in a plate.

Wisky/Wikimedia Commons (CC-BY-SA 3.0)

Diffraction (noun, “Dih-FRACK-shun”)

This is the bending or turning of a wave when it hits an object. The term often comes up in discussions of light hitting an edge or slit. The light wave is scattered in a pattern after hitting that slit or edge. The size of the scatter is related to the size of the object that caused the light to bend.

In a sentence

Using a laser pointer and the principles of diffraction, you can find out the thickness of a single human hair.

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Bethany Brookshire was a longtime staff writer at Science News Explores and is the author of the book Pests: How Humans Create Animal Villains. She has a Ph.D. in physiology and pharmacology and likes to write about neuroscience, biology, climate and more. She thinks Porgs are an invasive species.