Abstract

Infrared absorption spectra have become widely used for in situ determination of concentrations in complex mixtures. However, experimental accuracy is often limited by lack of knowledge of the baselines. The mathematical treatment described below allows the spectra to be superimposed on any background with a shape as complex as a parabolic one. The concentrations are thus accurately determined whatever the baseline of the mixture spectrum and even those of the calibration spectra. A mathematical proof of this property is given within the framework of the presently used method, and tests of the efficiency of the method are presented.

Baseline correction for stray light in log-ratio diode laser absorption measurements

Yedhu Krishna, Sean O’Byrne, and Joseph John Kurtz
Appl. Opt. 53(19) 4128-4135 (2014)

Cepstral analysis for baseline-insensitive absorption spectroscopy using light sources with pronounced intensity variations

Christopher S. Goldenstein, Garrett C. Mathews, Ryan K. Cole, Amanda S. Makowiecki, and Gregory B. Rieker
Appl. Opt. 59(26) 7865-7875 (2020)

Accurate determination of the vapor pressure of potassium using optical absorption

B. Shirinzadeh and Charles C. Wang
Appl. Opt. 22(20) 3265-3270 (1983)

Performance assessment and signal processing for range-integrated concentration measurement of gas species using supercontinuum absorption spectroscopy

Alexandre Dobroc and Nicolas Cézard
Appl. Opt. 51(35) 8470-8480 (2012)

Broadband continuous-wave technique to measure baseline values and changes in the tissue chromophore concentrations

Hadi Zabihi Yeganeh, Vladislav Toronov, Jonathan T. Elliott, Mamadou Diop, Ting-Yim Lee, and Keith St. Lawrence
Biomed. Opt. Express 3(11) 2761-2770 (2012)