Choosing the Ranges for Measuring the Reflectivity of a Prism Coupler in the Waveguide Spectroscopy of Thin Films

摘要

A criterion for selecting the best ranges for measuring the reflectivity of a prism coupler, based on minimizing the error in reconstructing the parameters of thin films using the least-square method, is proposed. The effectiveness of the criterion is demonstrated by solving the inverse optical problem for a SiO_x film deposited on a silicon substrate as an example.