A Bauernfeind prism is a type of reflecting prism used to deviate a beam of light by 45° to 60°, depending on its construction, while neither flipping nor rotating the image.
A Bauernfeind prism with 45° beam deviation is also known as a half-penta prism or semipentaprism.
A Bauernfeind prism is used together with a Schmidt roof prism to form a Schmidt–Pechan prism.
Applications
The Bauernfeind prism is commonly used in microscope tubes and in geodesy to deviate the path to the eyepiece in order make the device more ergonomic.
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