论文部分内容阅读
条纹计数法解调精度受限,而常用的高精度外差调频解调法(如相位生成载波法、线性调频法),在光源调频过程中伴生有幅度调制并且调制解调系统复杂。提出了一种基于双光纤光路相位解调的法布里-珀罗(F-P)位移传感器,原理上省去了光源调频过程,在提高检测精度的同时,成本与条纹计数法相当。与已有报道的双光路结构不同的是,该传感器对两干涉光路之间相位差无严格要求,安装调节简单,降低了传感器的工艺难度。位移测量实验结果表明,该传感器在0~500μm的测量范围内,线性度为1.1%,误差限值为±3μm。
The streak counting method has limited demodulation precision. However, commonly used high-precision heterodyne FM demodulation methods (such as phase generating carrier method and linear frequency modulation method) have amplitude modulation and modulation and demodulation system complicated in the light source frequency modulation process. A Fabry-Perot (F-P) displacement sensor based on the phase demodulation of the dual fiber optical path is proposed, which eliminates the need for the frequency modulation of the light source in principle and increases the detection accuracy at the same cost as the fringe counting method. Different from the dual optical structure that has been reported, the sensor does not have strict requirements on the phase difference between the two interference optical paths, and the installation and adjustment are simple, which reduces the difficulty of the sensor. Displacement measurement experiment results show that the sensor has a linearity of 1.1% and a limit of error of ± 3μm over the measurement range of 0 ~ 500μm.