摘要
提出了一种基于残余幅度调制确定频率调制光谱探测相位的方法。基于理论分析得出当频率调制光谱系统存在残余幅度调制且无样品气吸收时,光谱信号与探测相位的余弦成正比,可直接确定探测相位。通过采用低频电压控制电光调制器提高了探测相位的测量精度,通过与有吸收时频率调制光谱线型拟合获得的相位进行对比,偏差控制在0.04rad(2°)以内,证实了该方案的可行性,提高了探测相位的测量速度。
A method of determining the detection phase of frequency modulation spectroscopy based on the residual amplitude modulation is proposed. According to the theoretical analysis, when there is a residual amplitude modulation in the frequency modulation spectroscopy, the signal amplitude without absorption is proportional to the cosine of detection phase. Based on this result, the detection phase could be determined directly by experiment. In order to increase the measure accuracy, a low frequency voltage control is applied to the electro-optical modulator. Comparing with the detection phase given by fitting the lineshape of frequency modulation spectroscopy with absorption, the new measured detection phase shows a deviation of less than 0. 04 rad （2°）, which verifies thevalidity of the new detection method and raises the measure speed of detection phase.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2013年第5期308-313,共6页
Acta Optica Sinica
基金
国家973计划(2012CB921603)
国家863计划(2009AA063006)
国家自然科学基金(61127017、61275213、61205216、61108030、61178009、60908019)
山西省青年科学基金(2010021003-3、2012021022-1)资助课题
关键词
测量
频率调制光谱
探测相位
残余幅度调制
电光调制器
measurement
frequency modulation spectroscopy
detection phase
residual amplitude modulation
electro-optic modulator
