Porro Prism
Porro prism is a type of reflection prism which can be used to alter the orientation of an image. Light enters the large face of the prism, then hits on the roof, by total internal reflection twice from the roof, the beam exits again through the large face. An image traveling through a Porro prism is rotated by 180deg but not inverted.
Specifications
| Dimension Tolerance | + 0/ -0.2 mm |
| Surface Quality | 60/40 scratch and dig |
| Clear Aperture | > 80 % |
| Flatness | < λ/10@632.8 nm |
| Wavefront Distortion | < λ/4@632.8 nm |
| Deviation | 180° ± 10 arc seconds |
| Roof Angle Tolerance | < 5 arc seconds |
| Chamfer | Sharp roof, other protective chamfered |
| AR Coating | None. Upon request. |
Model
| Dia., mm | Height h, mm | Deviation | Coating | Material |
| 12.7 | 12.7 | 180° ± 10 arc seconds | Uncoated, AR400-700 nm, AR515-532 nm, AR1028-1064 nm | H-K9L/UVFS |