基于光纤激光器的有源腔气体吸收测量网络

有源内腔法气体吸收测量技术具有极高的灵敏度,通过对基于掺铒光纤激光器的有源气体测量系统的分析和静态测量结果表明,在激光器阈值附近系统的灵敏度最大。为了有效地抑制噪声,提高测量精度,在环行腔光纤激光器的基础上又提出了采用波长调制/二次谐波检测的测量方法,并采用1×N的波分复用(WDM)器件构建了有源传感网络。实验中采用了一个1×4的波分复用器,其通道对应于乙炔气体的吸收波长,系统的解调通过扫描可调谐光滤波器的波长来实现。通过对8.31mol/m3的乙炔气体的实验表明系统最小可探测气体浓度为0.044mol/m3。

Intra-Cavity Absorption Gas Measurement Network Based on the Fiber Lasers

High sensitivity of the intra-cavity absorption gas sensor (ICAGS) measurement network based on the erbium doped fiber ring laser was demonstrated. It is found that the maximum sensitivity can be obtained when the laser is operating near the threshold. Wavelength modulation/second harmonic detection technique was used to improve the performance of intra-cavity absorption measurement. A 1×N wavelength division multiplexer (WDM) with one channel corresponding to the absorption line of acetylene within the transmission window of 1530 nm was used in the WDM active sensing network. The system is demodulated by scanning the wavelength of a tunable filter. The minimum detectable gas concentration of 0.044 mol/m3 was achieved in measuring the 8.31 mol/m3 acetylene gas.