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Extension of the Norton-Beer apodizing functions in Fourier transform spectrometry
1Key Laboratory of Photoelectronic Imaging Technology and System (Beijing Institute of Technology), Ministry of Education of China, Beijing, China.
Applied Optics
|July 12, 2012
Summary
New apodizing functions improve Fourier transform spectrometry by reducing spectral smearing and enhancing the instrumental line shape (ILS). These functions offer greater flexibility for distinguishing weak spectral lines compared to Norton-Beer methods.
Area of Science:
- Spectroscopy
- Mathematical Physics
Background:
- Apodization is crucial in Fourier transform spectrometry (FTS) for mitigating spectral artifacts.
- Norton-Beer functions are standard apodizing tools but have limitations in spectral resolution.
Purpose of the Study:
- To introduce a novel family of apodizing functions for FTS.
- To enhance the instrumental line shape (ILS) convergence and reduce spectral smearing.
- To improve the ability to resolve weak spectral lines.
Main Methods:
- Investigated Norton-Beer apodizing functions.
- Developed new functions based on the main series expansion.
- Applied functions to weigh interferograms to zero within the same optical path difference.
Main Results:
- The new functions continuously weigh the interferogram to zero.
- Improved convergence properties of the instrumental line shape (ILS).
- Significantly reduced the range of spectral smearing.
- Demonstrated enhanced capability in distinguishing weak spectral lines.
Conclusions:
- The novel apodizing functions offer practical advantages over Norton-Beer functions.
- These functions provide greater flexibility and applicability for spectral analysis.
- Improved resolution of weak spectral lines susceptible to ringing artifacts.
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