Assertion: porro prism | /r/ObjectUse | used in periscope
Facets:
Source sentences:
text: The Porro prism, for example, consists of two prisms arranged both to invert and to reverse an image and are used in many optical viewing instruments, such as periscopes, binoculars, and monoculars.
text: The Porro prism, for example, consists of two prisms arranged both to invert and to reverse an image and are used in many optical viewing instruments, such as periscopes, binoculars, and monoculars.