light box

American  

noun

1. a boxlike object having a uniformly lighted surface, as of ground glass, against which films or transparencies can be held for examination.

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light box British  

noun

1. a light source contained in a box and covered with a diffuser, used for viewing photographic transparencies, negatives, etc

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Etymology

Origin of light box

First recorded in 1840–50

Example Sentences

If it’s too dark when you get up, especially in the winter, use a light box or an alarm clock like the Hatch Restore 3, which slowly lights up to ease you out of slumber.

From The Wall Street Journal • Jan. 11, 2026

There are also two wall-mounted light box installations in the Broadway and Grand Avenue stations, part of a rotating art program.

From Los Angeles Times • Jun. 17, 2023

The artist is building a literal stone wall as a kind of monument around a light box presenting a photograph taken in their hometown, Detroit, with “DYKE” spray-painted on a building.

From New York Times • Apr. 27, 2022

Both groups received an hour of treatment from a light box for two weeks.

From Salon • Apr. 21, 2022

Dr. Howard told me that even if the light box works, it will take a few months to start seeing any improvement, but I still glance down at myself afterward.

From "How to Disappear Completely" by Ali Standish