Second Harmonic Phase Angle Method Based on WMS for Background-Free Gas Detection
نویسندگان
چکیده
We propose a second harmonic phase angle method (WMS- $\theta _{2f}$ ) based on wavelength modulation spectroscopy for trace gas detection. WMS- exhibits the advantages of background-free and immunity to light intensity fluctuations. The detection sensitivity is 1-2 orders magnitude higher than that first method. Moreover, there room further improvement in by optimizing linearity laser. verified feasibility experimentally theoretically, respectively.
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ژورنال
عنوان ژورنال: IEEE Photonics Journal
سال: 2021
ISSN: ['1943-0655', '1943-0647']
DOI: https://doi.org/10.1109/jphot.2021.3113503