beam splitter

American  

noun

Optics, Photography.

1. a mirror or prism that divides a beam of light into two parts by reflecting a part of the beam, used in camera range finders.

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beam splitter British  

noun

1. a system that divides a beam of light, electrons, etc, into two or more paths

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Etymology

Origin of beam splitter

First recorded in 1930–35

Example Sentences

Because of that key difference, as the beam splitter itself expands and contracts, the light detector would pick up a signal.

From Science Magazine • Dec. 15, 2021

In their experiment, preselected neutrons with a particular spin were sent, one by one, into a beam splitter, which is a device that splits a beam of particles into two.

From Scientific American • May 6, 2019

Instead, the first beam splitter sends the photon down one path or the other, like a particle.

From Science Magazine • Oct. 27, 2017

Remove the second beam splitter and interference becomes impossible.

From Science Magazine • Oct. 27, 2017

But they made the choice only after the photon had passed through the beam splitter.

From Scientific American • Nov. 6, 2012