Definition of light valve
: an electromagnetically operated device whose light transmission varies in accordance with an electrical quantity (as current) and that is used especially in recording sound on motion-picture film
Start your free trial today and get unlimited access to America's largest dictionary, with:
- More than 250,000 words that aren't in our free dictionary
- Expanded definitions, etymologies, and usage notes
- Advanced search features
- Ad free!
Seen and Heard
What made you want to look up light valve? Please tell us where you read or heard it (including the quote, if possible).