eyepiece has definitions from the fields of physics,optics
1
[ noun ] (physics,optics) combination of lenses at the viewing end of optical instruments

Synonyms

ocular

Used in print

(A. N. Nagaraj and L. M. Black, "Localization of...)

In the eyepiece a Wratten 2 B filter was used to filter off residual ultra-violet_light .

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