Old School Versus New in Optical Topology Testing
Dec 2, 2009 — For the past 100 years or so, makers of optical components have relied on Fizeau interferometers to check surface quality. These devices have allowed manufacturers to detect defects via deviations from regular fringe patterns. However, Fizeau interferometers require very accurate references, which must be tailored for each surface type. Twyman-Green interferometers, however, sidestep this requirement. Not only is the Twyman-Green more flexible, say supporters, but also the need for calibration...