Porro prism

[ pawr-oh ]
/ ˈpɔr oʊ /

noun Optics.

an isosceles, right-triangular prism in which light entering one half of the hypotenuse face is reflected at the two short sides and is reversed in orientation when it leaves the other half of the hypotenuse: used in 90°-oriented pairs in binoculars to increase the length of the optical path and to erect the final image.

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DO YOU KNOW THIS VOCABULARY FROM "THE HANDMAID'S TALE"?

"The Handmaid's Tale" was required reading for many of us in school. Everyone else has probably watched the very popular and addictive TV show. Do you remember this vocabulary from the book, and do you know what these terms mean?
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decorum
the act of or need for making up one's mind.
dignified propriety of behavior, speech, dress, etc.
a company of singers, especially an organized group employed in church service.
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Origin of Porro prism

named after Ignazio Porro (1801–75), Italian engineer
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020