ABSTRACT: A paper by An and Parks describing a method of calculating the vertex radius of an off-axis parabolic segment using a three ball spherometer to measure the sag. The vertex radius is found by solving a set of six simultaneous, non-linear equations for the three coordinates of the ball centers and the corresponding three coordinates of the point of contact of the ball with the parabolic surface.
ABSTRACT: Describes using the Point Source Microscope to find the vertex radius and off-axis distance of off-axis parabolic mirrors by measuring the distance between the sagittal and tangential astigmatic foci and the mirror.
"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!"