
Dynamic computational optical fringe mitigation in tunable laser absorption spectroscopy
Author(s) -
Chu C. Teng,
Eric Zhang,
Chi Xiong,
William M. J. Green,
Gerard Wysocki
Publication year - 2020
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.413053
Subject(s) - optics , spectrometer , calibration , materials science , laser , spectroscopy , fabry–pérot interferometer , scattering , absorption (acoustics) , photonics , physics , quantum mechanics
In optical spectroscopic systems where unwanted optical scattering cannot be eliminated, Fabry-Pérot etalons cause unpredictable changes in the spectral background. Frequent system calibration is then required to maintain the desired measurement accuracy, which presents a major limitation to the spectrometer. We introduce a computational approach to mitigate the adverse effects of optical fringing without hardware modifications. Motivated by experimental observations of complicated fringe behaviors, we simplify the problem by decomposing the fringe background into component etalons that can be addressed according to their individual characteristics. The effectiveness of the proposed method is demonstrated on a silicon photonic methane sensor, where accurate measurements of methane concentration are obtained from spectral data strongly affected by optical fringes.