Roof prism

The roof prism is small in size and can align the objective lens and eyepiece in a straight line, so it is often used in extremely compact binoculars.

The key feature of a roof prism lies in the presence of a roof surface. The so - called roof surface is a reflective surface in the optical path formed by two reflective surfaces in a roof - like shape. The edge of the two surfaces is in the middle of the optical path. So, in some roof prisms, a dividing line can be seen in the middle. In fact, it can also be understood as splitting the light beam into two halves and then recombining them. 

Technical Parameters

Size tolerance (mm): ±0.1mm

Clear aperture: ≥90%

Surface figure accuracy: λ/5

Angular tolerance: 3"

Surface quality: 40/20

Chamfer accuracy: ±0.1

Two - way difference: 15"

Side perpendicularity: <3