roof prism


Definition of roof prism

: a glass prism used in an optical range finder and other instruments that performs the double function of changing the direction of the light rays by 90 degrees and reversing the image right to left — compare porro prism

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First Known Use of roof prism

1904, in the meaning defined above

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The first known use of roof prism was in 1904

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Cite this Entry

“Roof prism.” Dictionary, Merriam-Webster, Accessed 30 Sep. 2020.

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