Abstract
Microgratings that were designed and fabricated to generate IR absorption spectra of SF6 and NH3 on diffraction into a specific detection angle were tested by correlation spectroscopy. The micrograting diffraction provides a reference spectrum for a target molecule, and its cross‐correlation with the transmission spectrum of a gas cell is obtained by varying the diffraction angle. As our optical setup can measure the dispersive transmission spectrum and the correlation spectrum under the same conditions, the two kinds of spectra were compared directly in terms of signal‐to‐noise ratio (SNR). The SNR’s of the correlation spectra were a few times lower than those of the dispersed spectra; therefore, the correlation spectroscopy can hardly be placed above the dispersive spectroscopy with respect to the SNR. The merit of the correlation spectroscopy is that a rather small range of modulation wavelength is needed to identify the target. Therefore, the correlation spectroscopy would be more useful for such target molecules whose spectra consist of broad peaks spread throughout a wide wavelength range.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
