A general method of calculating the integral-order number of interference is developed, completely without a trial method. The developed method of excess fractions is extended to the calibration of the effective optical thickness of a Fabry-Perot 6talon with the disperion of the refractive index and the phase shift on reflection. Several useful methods of calibration are provided and illustrated by examples. The condition under which the phase shift can be neglected is given for calculating the correct integral-order difference between wavelengths. A possible method of precise measurement of the dispersive phase shift is given. It is pointed out that exact knowledge of the integral order is not even necessary and that the phase shift can thus essentially be neglected for a precise measurement of the wavelength as long as the effective optical thickness is calibrated as the product of the fringe order of interference and the standard wavelength.
© 1989 Optical Society of America
Shidong Zhu, "Developed method of excess fractions for calibrating the effective optical thickness of a Fabry–Perot etalon," J. Opt. Soc. Am. A 6, 500-507 (1989)