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

This light box learning tool uses contrasts to help encourage young kids with impaired vision develop awareness of objects, light and color.

From Los Angeles Times • Oct. 14, 2025

I think my favorite bit of production design in the whole movie is in the apartment, the oversized light box on the wall of what looks like a suit containing no man.

From Salon • Apr. 14, 2025

My favorite thing to do was to look through the loupe at slides on the light box.

From New York Times • Apr. 20, 2023

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