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There is no better way to describe an autostigmatic microscope (ASM) than to call it an autocollimator (AC) with a microscope objective attached to the front. This converts the AC from an instrument that measures 2 angular degrees of freedom (DOF) into an instrument that measures the location of the center of curvature of a […]

Authors: Robert E. Parks (Optical Perspectives Group, LLC) and Daewook Kim (J. C. Wyant College of Optical Sciences, University of Arizona). INTRODUCTION Following the discovery of so called non-diffracting Bessel beams[1], they have been used for a number of exotic purposes such as trapping single atoms and aiding in the discovery of exoplanets. We discuss more […]

Fig. 1 A simple collimator with a point source of illumination. An illuminated target in the same plane could serve as the source. Collimators are used as a light source for testing camera lenses on a nodal slide optical bench. The collimator simulates a point source, or in astronomical terms, a star, at infinity. For lens […]

In the Introduction to this series of articles on optical alignment, I said there were three basic methods of alignment. This article presents my thoughts on these methods. My approach may be a bit unconventional, but I hope this way of beginning makes the whole idea of alignment easier to understand. To illustrate the three […]

Introduction to a Series of Articles on Optical Alignment For some time, I have been encouraged to write a book about optical alignment. There have been several half-hearted attempts at beginning, but it never seemed there was enough to talk about and I kept finding new ideas about alignment. I didn’t want the book to […]

Back in the late 1990’s NIST had a number of firms that wanted to send their interferometer transmission spheres there for calibration but NIST was not in this sort of calibration business. While I was at NIST consulting for Chris Evans in the Precision Machining Facility we thought of the idea of a self-calibration test […]