Applications of Optical Interferometer Techniques for Precision Measurements of Changes in Temperature, Growth and Refractive Index of Materials: A Brief Review

Different interferometer techniques and their applications are surveyed. The principle of optical heterodyne detection and its applications to in situ measurement of crystal growth rate, surface roughness measurement of coated mirrors and temperature changes due to laser heating are described in detail. Application of fluorescence ratio method, fluorescence lifetime measurement, Michelson interferometer and Mach-Zehnder interferometer techniques, for the measurement of temperature changes, are described in detail. The use of Mach-Zehnder interferometer to monitor changes in solution refractive index or concentration is described. A detailed error analysis is given for some of the measurements.