Water Vapor Detection System Based on Scanning Spectra

• Published in: Photonic sensors (Berlin) Vol. 2; no. 1; pp. 71 - 76
• Main Authors: Zhang, Shicong, Wang, Qiang, Zhang, Yan, Song, Fujun, Chen, Kun, Chou, Guoqing, Chang, Jun, Wang, Pengpeng, Kong, Delong, Wang, Zongliang, Wang, Weijie, Liu, Yongning, Song, Haiyong
• Format: Journal Article
• Language: English
• Published: Beijing University of Electronic Science and Technology of China 01.03.2012
• Subjects: LabVIEW; Lasers; Measurement Science and Instrumentation; Microwaves; Optical Devices; Optics; Photonics; Physics; Physics and Astronomy; Regular; RF and Optical Engineering; 低通滤波器; 光谱吸收; 压力范围; 检测系统; 水汽; 波长扫描; 温度变化; detecting under high gas pressure; near-infrared absorption; Water-vapor detection; scanning spectra
• ISSN: 1674-9251; 2190-7439
• DOI: 10.1007/s13320-011-0038-z

Scanning the absorption spectral line of water vapor through wavelength around 1368.597nm is successfully used to measure the value of micro-moisture content. The synchronous superposition average of original signal algorithm based on labview is innovated and applied to detecting weak spectrum absorption signal instead of low pass filter. Two data processing methods are used to get the concentration of water vapor in ppm： one is a general formula method which has newly deduced a general formula to calculate the concentration of gas with temperature and beam intensity ratio when the pressure is equal to or greater than 1 atm; the other is engineering calibration method which is proved to have high resolution and accuracy with the fitted curve of beam intensity ratio and concentration in ppm when the temperature changes form 258K to 305K and the pressure ranges from 1 atm to 5 atm.