1A reflecting prism in which the light is reflected on two 45° surfaces and returned parallel to the incoming beam. Compare with roof prism.
More example sentences
- While not as sexy as a roof prism, the porro prism is a dependable unit made for the outdoors.
- Two porro prism binocular models are new, the 8x42 mm and the 10x42 mm.
- Modern roof prism designs are capable of performance just as good as a comparable porro prism design, due to current technology such as phase coating and improved reflective backing materials on the prisms.
named after the Italian scientist Ignazio Porro (1801–75).
Definition of Porro prism in:
- The US English dictionary