Abstract
Two multi-harmonic detection methods for wavelength modulation spectroscopy (WMS) systems are presented and compared. The two possibilities discussed in this paper are: simultaneous curve fitting of multiple harmonic spectra, and reconstruction of the transmission from harmonic coefficients. The optimum number of harmonics is four and 25 harmonics, respectively. Compared with standard single-harmonic curve fitting, the methods give about a factor of 3 better performance than standard second-harmonic curve fitting. Concluding, multi-harmonic detection is better than single-harmonic detection and should be used if the system bandwidth is high enough to allow for proper detection of the higher harmonics.
| Original language | English |
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| Pages (from-to) | 177-185 |
| Number of pages | 9 |
| Journal | Applied Physics B: Lasers and Optics |
| Volume | 110 |
| Issue number | 2 |
| DOIs | |
| State | Published - Feb 2013 |