size of splitter(mm):
Splitter rotation:
(even for F/2 mirror, 2 degrees is more than enough to get those 2 laser dots out of the test beam)
Distance from splitter center to diverger
Width of mirror/flat
Laser beam offset from splitter center
Laser beam width(mm)
(include full beam - not just usable beam. If any of reference beam reflects off inside of cube then that is a problem. Hitting the edge of the flat can be a problem also as the edge of the flat can create lots of weird reflections)
Splitter IOR
X Tilt:
(Wyant waves)
Defocus:
(Wyant waves)
Green dot is where to focus returning test beam when setting things up (temporarily lower bath so returning beam passes over splitter and flat) Formula is: beam_separation_distance + diverger_focal_length behind diverger)
Yellow dot is CoC of mirror being tested. Measure from here to mirror surface and divide by 2 to find focal length of mirror. Formula for CoC position is: beam_separation_distance/2 behind diverger