Roof Prism

Roof prisms, also called “Amici prisms, Dach prism” or “right angle roof prisms, many name, same prism.

Characteristic for a roof prism is that the beam is split in half, with one half of the beam hitting first one face then the other face, while it is invert for the other half of the beam. Therefore, a roof prism can be used only with some distance to focal planes, or the "edge" of the roof would introduce slight distortions. Furthermore, the angle between the two faces has to be very close to 90°, or image quality would be degraded.
Roof prism deflects the beam, through an angle of 90 degree and inverts the image. For this reason, this prism is perfect for erecting images inverted by the objectives.
Used in Binoculars, Spotting Scopes, Microscopes and Telescope Eyepieces.

 Parameters

Standard

High Pricision

  Material

N-BK7, Fused Silica, Custom

  Size

0.5mm-380mm

  Size tolerance

±0.1mm

±0.03mm

  Angle Tolerance

<3'

<0.5''

  Clear Aperture

≥90%

100%

  Surface Quality

60/40, 40/20

20/10, 10/5

  Surface Flatness

1/2 lambda, 1/4lambda

1/10Lambda, 1/20Lambda

  Parallelism

+/-3' , +/-30''

<0.5''

  Bevel

<0.2mm±45°

No Bevel (The Angle is unbroken)

  Coating

Uncoated, AR, BBAR, Reflective