entrance pupil

noun

: the stop in an optical instrument or the virtual image of the stop that determines the angular diameter of the bundle of rays traversing the instrument from a given point in the object space compare exit pupil

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Cite this Entry

“Entrance pupil.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/entrance%20pupil. Accessed 25 Jul. 2024.

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