A paper by Sykora of Zygo showing that the Random Ball Test (RBT) works less and less precisely as the numerical aperture of the transmission sphere becomes smaller. In other words, the RBT works best for fast transmission spheres and another means of calibration should be used for slow test optics.
ABSTRACT: A paper by authors at NIST about simulations and experiments done with the Random Ball Test (RBT) giving criteria for establishing the precision of transmission sphere calibration using the RBT.
ABSTRACT: A paper by Creath and Wyant explaining the method of calibration of surface roughness interferometers. This same method is used in the Random Ball Test (RBT) except that the random surface over which interferograms are averaged is not a plane but a sphere.
ABSTRACT: A readable copy of the original paper on the Random Ball Test (RBT) authored at NIST that was published in a non-archival meeting journal. Even here the figures are not legible. For better example figures see "A practical implementation of the random ball test".
ABSTRACT: A study by Burke and Wu of CSIRO comparing several methods of transmission sphere calibration that concludes the Random Ball Test (RBT) has the highest precision of all the methods tried though it is tedious to perform for highest precision if the RBT is not automated.
ABSTRACT: Paper by W. Cai, et. al., comparing experimental results in the Random Ball Test (RBT) between using a clean ball and systematic measurement versus a somewhat dirty ball and casual measurement. The results gave identical precision within reasonable statistical limits.
ABSTRACT: The most common use of the Point Source Microscope (PSM), or any autostigmatic microscope, is the precision measurement of the radius of curvature of spherical surfaces. This note describes the procedure for doing so and defines confocal and Cat's eye focus.
ABSTRACT: Another paper by Burke and Wu at CSIRO that says the Random Ball Test (RBT) is the most precise method for calibrating fast transmission spheres but that it is tedious for highest precision unless automated.
"Just wanted to share a recent success aligning an adaptive optics test bed with the PSM. We used to use a traditional alignment telescope in the past, but the PSM made the whole process really easy and fast. The main requirements were to quickly determine the quality of beam collimation and pupil conjugates since there are several beam expanders and compressors with multiple pupil and focal planes."
Suresh Sivanandam Dunlap Institute for Astronomy and Astrophysics University of Toronto
"You are always responsive and give us lots of useful information!!"
Dr. Shaojie Chen Dunlap Institute for Astronomy and Astrophysics University of Toronto
"As always we are very much loving the instrument, I personally love the camera upgrade from what I'm used to!"