Published in Applied Optics, Volume 44, Issue 3, January 25, 2005, pages 344-347.
Copyright © 2005 Optical Society of America. This paper was published in Applied Optics and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/doi:10.1364/AO.44.000344. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.
NOTE: At the time of publication, the author Glen Gillen was not yet affiliated with Cal Poly.
We present a method to independently measure the refractive index and the thickness of materials having flat and parallel sides by using a combination of Michelson and Fabry-Perot interferometry techniques. The method has been used to determine refractive-index values in the infrared with uncertainties in the third decimal place and thicknesses accurate to within ± 5 µm for materials at room and cryogenic temperatures.