entrance pupil

noun Optics.
the image of the aperture viewed from the objective of an optical system limiting the rays that enter the system.
Compare exit pupil.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To entrance pupil
Explore Dictionary.com
Previous Definition: entrance money
Next Definition: entrance ramp
Words Near: entrance pupil
More from Thesaurus.com
Synonyms and Antonyms for entrance pupil
More from Reference.com
Search for articles containing entrance pupil
More from Dictionary.com Translator
Dictionary.com Word FAQs

Dictionary.com presents 366 FAQs, incorporating some of the frequently asked questions from the past with newer queries.

Example sentences
Also, the incandescent arc of the lamp must fill the entrance pupil of the condenser.
The ratio of the effective focal length of an optical system to the diameter of the entrance pupil.
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature