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

Again, the delayed decision seems to reach back in time, defining how the photon behaved after it left the first beam splitter.

From Science Magazine • Oct. 27, 2017

The beams reflect off mirrors and race back to the beam splitter.

From Science Magazine • Aug. 4, 2016

One might suspect that photons simply assume one of two behaviors—wave or particle—beforehand, or when they hit the beam splitter.

From Scientific American • Nov. 6, 2012

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

From Scientific American • Nov. 6, 2012