摘要
在传统的激光多普勒测振方法中,频移信号的检测通常需要具有比较复杂的频率或相位解调系统。从激光多普勒频移和干涉理论出发,提出了一种测量振幅小于纳米量级的方法———直接强度解调法。分析了直接强度解调法的适用范围。实验中利用了迈克尔逊干涉仪结构,采用了直接强度解调的方法。对振幅约为1nm的振动信号来说,其信噪比为23dB。
Conventional Doppler vibration measurement methods generally revolved complicated frequency or phasc demodulation system. A simple method to measure micro vibration was set forth according to laser Doppler frequency shifts and interference theory. Applicability of this method, which was direct intensity demodulation method, is analyzed. Michclson interferometer and direct intensity demodulation mctbod were used in experiments. The experiment results show that SNR is 23dB when the vibration amplitude is about 1 nm, which means that can use direct intensity demodulation method to measure vibration signal with amplitude less than 1 nm.
出处
《光学技术》
EI
CAS
CSCD
北大核心
2005年第4期563-564,567,共3页
Optical Technique
基金
安徽省优秀青年科技基金资助项目(04042045)
安徽省高等学校青年教师科研资助计划项目(2004jq111)
关键词
多普勒
微振动
直接强度解调
干涉
Doppler
micro vibration： direct intensity demodulation
interference
