Quasimonochromatic light sources, such as laser diodes and high power LEDs, are investigated to determine their suitability for zero path difference determination using white light fringes in a Michelson interferometer. Fringe visibility curves are theoretically determined for various combinations of light sources and compared with experimental results when used in a Michelson interferometer with a 25-m path length. A resolution of 2–3 μm was obtained for a pair of multimode laser diodes and also for a single multimode laser diode operated as an LED. This is more than adequate for the calibration of survey baselines.
© 1991 Optical Society of AmericaFull Article | PDF Article