A Model for Cavity Induced Errors with Wavefront Slope in High Accuracy Spherical Fizeau Metrology (ABSTRACT)
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 note describing the Random Ball Test (RBT) for calibrating interferometer transmission spheres by averaging a number of interferograms taken of different, randomly positioned, patches of a precision silicon nitride ball.
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: An autostigmatic microscope is a perfect way of aligning an autocollimating flat mirror to a parabola. This notes descibes the simple two step process of positioning the PSM objective focus coincident with the focus of the parabola.
ABSTRACT: It is sometimes necessary to align a series of optical elements, lenses and mirrors, to a single, straight optical axis. This note describes a method using an autostigmatic microscope (ASM) where the ASM is moved along a straight line relative to the axis of the bench in which the elelemts are mounted so the centers of curvature of the elements can be adjusted to lie on the line or axis of the system.
ABSTRACT: Paper by Oh describing the use of an autostigmatic microscope (PSM) to precisely position computer generated hologram (CGH) alignment targets on optical surfaces.
ABSTRACT: Describes the advantages of aligning optical systems using a Point Source Microscope (PSM) where the optical axis of the system is folded in 2 or 3 dimensions and shows how pseudo aberrations can be generated that show quantitatively the degree of precision of the alignment from the Star image seen in the PSM.
ABSTRACT: Stover, et. al., show that scatter in transmission through a window may be calculated from surface roughness in a manner similar to calculating BRDF from roughness for a reflecting surface.
Calculation of the Vertex Radius of an Off Axis Parabolic Surface using the Sag Measured with a Three Ball Spherometer (ABSTRACT)
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: 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: Desribes step-by-step how to calculate the locations of the centers of curvature of optical elements to be centered, and how to set up one or two PSM's to center the lenses as they are assembled on a rotary table. Also discussed are practical issues relating to the hardware, and calculation of sensitivites to alignment.
ABSTRACT: The concept of centering a precision, symmetric lens system using a high-quality rotary table and an auto-focusing test instrument are well known. Less well known are methods of finding convenient, or easily accessible, lens conjugates on which to focus while performing the centering operation. We introduce methods of finding suitable conjugates and centering configurations that lend themselves to practical centering solutions.
ABSTRACT: Paper by Coyle describing the use of an autostigmatic microscope (PSM) along with computer generated hologram (CGH) targets for the alignment of optical systems.