Abstract

Interferometric measurements have found widespread usage in the field of optics due to their high sensitivity. In particular, measuring a displacement for range-finding may be achieved with subwavelength precision using interferometers [1]. This, however, relies upon a careful calibration of the interferometer in order to map phase shift to displacement.The effects of classical noise are mitigated by operating at high frequencies (> 1 MHz), where the calibration becomes considerably more difficult due to a decrease in the responsivity of the modulated element. We develop here a method that achieves a shot-noise limited absolute calibration without any assumption on the nature of the optical field or the theoretical limits of detection [2].

© 2015 IEEE