一种基于法布里-珀罗干涉仪的位移测量方法

A Displacement Measurement Method Based on Fabry-Perot Interferometry

介绍了一种基于法布里-珀罗干涉仪的位移测量方法,为了克服通常的法布里-珀罗干涉仪在位移测量范围方面的局限,采用两束可调激光分别对法布里-珀罗腔的两个相邻谐振峰的光频率进行追踪测量,能够得到任意时刻法布里-珀罗腔的长度,从而实现对测量镜位移的测量,测量范围可以达到毫米量级。对影响测量精度的主要因素进行了简要分析,结果表明采用本方法能够实现纳米级精度位移测量。

A displacement measurement method based on Fabry-Perot interferometer is introduced. In order to overcome the limit in displacement measurement range of usual Fabry-Perot interferometer, the length of the Fabry-Perot cavity is measured by tracing the frequencies of two adjacent resonance peaks using two frequency-tunable lasers to obtain the displacement of the measurement mirror. The measurement range can be expanded to millimeter level by using this method. The main factors that affect the measurement accuracy are analyzed briefly and the result shows that the displacement measurement accuracy at nanometer level can be achieved by using this method.