15 October 2013 Wide absorption spectrum measuring methods by DFB-LDs in water vapor detection system
Author Affiliations +
Proceedings Volume 8924, Fourth Asia Pacific Optical Sensors Conference; 89242S (2013) https://doi.org/10.1117/12.2031608
Event: Asia Pacific Optical Sensors Conference 2013, 2013, Wuhan, China
Abstract
Two measuring methods of wide absorption spectrum by DFB-LDs are presented in detecting water vapor absorption line. One is subsection scanning method, it takes advantage of wide spectrum tuning range by temperature modulation and fast spectrum tuning speed by current modulation, specifically, this method is realized by dividing a target spectral region into several sections which corresponding to specific temperature of DFB-LD, and scanning every section by current modulation for hundreds times and average the data to raise SNR, combining all sections to get the whole spectrum. An accuracy of 10 ppmv had been obtained in the measurement of water vapor with a 10-cm path length by this method. Another is data fitting method, based on absorption line-shape function, the absorption line can be described by fitting with partial measured data. The fitting absorption line is fitted well with the measured data, and the square of correlation coefficient (R-square) is no less than 0.99.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Y. N. Liu, J. Chang, J. Lian, Q. Wang, G. P. Lv, W. J. Wang, Z. Liu, X. Z. Liu, S. S. Zhang, Z. L. Wang, S. Jiang, C. G. Zhu, W. Wei, B. N. Sun, "Wide absorption spectrum measuring methods by DFB-LDs in water vapor detection system", Proc. SPIE 8924, Fourth Asia Pacific Optical Sensors Conference, 89242S (15 October 2013); doi: 10.1117/12.2031608; https://doi.org/10.1117/12.2031608
PROCEEDINGS
4 PAGES


SHARE
Back to Top