根据边孔光纤光栅两反射峰偏振态相互正交的特性,提出了一种新颖的基于偏振检测的双峰间距测量方案。该方案采用全保偏光纤系统和偏振器实现了2个反射峰中心波长的分别检测,从而达到双峰间距的测量目的。采用该方案解决了普通波长扫描技术中存在的由于双峰间距较小而导致不能有效测量双峰间距的问题,成功实现了在0.0~3.5MPa压力范围内的边孔光纤光栅压力传感。
Utilizing the property that the polarizations of the two reflection peaks of side hole fiber grating are orthogonal, the article has put forward a novel scheme to measure peak separation on the basis of polarization detection. The peak separation is achieved by measuring the two peaks' center wavelengths respectively with all polarization maintaining fiber system and polarization analyzer. The side hole fiber grating pressure sensing within the range of 0.0-3.5 MPa is realized successfully by the new scheme,which solves the problem that the peak separation can not be measured by the ordinary wavelength scanning technique when the peak separation is too little.