Table 1 Parameters of the round robin specimens
From: Round robin comparison study on the form measurement of optical freeform surfaces
Property | Two-radii | Convex toroid | Concave toroid |
|---|---|---|---|
Material | Super Invar ® | Super Invar ® | Super Invar ® |
Diameter | 40 mm | 50 mm | 100 mm |
Markers | none | 4 Gaussian peaks; different depths | none |
Radius of curvature | r1=39.5 mm | rv=40 mm | rv=400 mm |
r2=40 mm | rh=42 mm | rh=450 mm | |
Designed by | PTB | PTB | PTB |
Manufacturer | IPP | IPP | IPP |