When referring to the scientist the proper pronunciation of Fresnel is 'Fraynel'; it was his name after all. When referring to the lens the pronunciation 'freznel' is accepted. Like many foreign words the pronunciation has become westernized.
Main Entry: Fres·nel lens
Pronunciation: 'frez-n&l-, frA-'nel-
Function: noun
Etymology: Augustin J. Fresnel
: a lens that has a surface consisting of a concentric series of simple lens sections so that a thin lens with a short focal length and large diameter is possible and that is used especially for spotlights
From:
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