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Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
Phase determination for a Fourier transform infrared spectrometer in emission mode
Anne Kleinert1, Olaf Trieschmann
1Institut für Meteorologie und Klimaforschung, Karlsruhe, Germany. anne.kleinert@imk.fzk.de
Applied Optics
|April 7, 2007
Summary
Fourier transform spectrometer (FTS) emission spectroscopy requires accurate phase determination. A new statistical method minimizes spectral phase errors, achieving 10-30 mrad accuracy for improved calibrated spectra.
Area of Science:
- Spectroscopy
- Optical Engineering
- Physical Chemistry
Background:
- Beam-splitter emission significantly impacts Fourier transform spectrometer (FTS) measurements, particularly in emission spectroscopy.
- Different radiation sources within an FTS possess distinct phase behaviors in the complex spectrum.
- Classical phase correction methods can introduce errors by mixing spectral components with varying phases.
Purpose of the Study:
- To investigate the nature of phase behavior in Fourier transform spectrometers.
- To develop a novel statistical method for accurate phase determination in FTS.
- To improve the accuracy of calibrated spectra by addressing phase-related errors.
Main Methods:
- Developed a statistical phase determination technique for FTS.
- Minimized correlation between real and imaginary parts of the complex spectrum.
- Reduced the variance of the imaginary part of the spectrum.
Main Results:
- Achieved phase accuracies of 10 to 30 milliradians (mrad).
- Enabled calculation of remaining phase error for individual spectra.
- Demonstrated a method to overcome errors caused by mixing different phase radiation components.
Conclusions:
- The developed statistical method provides accurate phase determination in FTS.
- This approach significantly reduces spectral calibration errors.
- The method allows for quantifying residual phase errors, enhancing spectral data reliability.
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