title: [Experimental study on harmonic detection of methane by use of a digital lock-in amplifier].
abstract: The harmonic detection of methane at 6105.3694 cm(-1) was measured by use of a digital lock-in amplifier (SR830) remotely controlled by a computer. The programme was written by Visual Basic 6.0 because it has strong function and a friendly appearance. The experimental results are in agreement with theoretical analysis, which fully confirms that a better signal-to-noise ratio (SNR) can be achieved in the high-harmonics detection of trace gases by the digital lock-in amplifier. The method can be applicable to the highly sensitive detection of pollution gases.
authors: College of Physics and Electronics Engineering, Shanxi University, State Key Laboratory of Quantum Optics and Quantum Optics Devices, Taiyuan 030006, China.
authors: Lei
authors: L
authors: Dong
authors: Wei-Guang
authors: WG
authors: MA
authors: Wang-Bao
authors: WB
authors: Yin
authors: Chang-yong
authors: CY
authors: Li
authors: Suo-tang
authors: ST
authors: Jia
mesh_terms: D000393:Air Pollutants / Q000032:analysis / Q000737:chemistry; D000465:Algorithms; D000669:Amplifiers, Electronic; D008697:Methane / Q000032:analysis / Q000737:chemistry*; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D013053:Spectrophotometry / Q000295:instrumentation / Q000379:methods*
chemical_list: D000393:Air Pollutants; D008697:Methane