为了精确测量非消色差波片的延迟量与快轴方位角，基于拟合光强法与光谱分析法建立了一套高精度测量系统，实现了特定波长下非消色差波片延迟量在0°～360°的高精度测量。对波片延迟量的测量方法及误差来源进行了详细的模拟分析。在拟合光强法下，重点仿真了光源光强抖动变化、检偏器初始安装精度、旋转波片定位精度等随机误差与各项系统误差对测量精度的影响，详细分析了拟合光强法不能精确测量波片延迟量为180°的原因。在光谱分析法下模拟了光源光强抖动变化、光谱的单色精度、检偏器定位精度引入的测量误差。在测量系统的建立中对上述两种测量方法影响较大的误差均进行了抑制，并对探测器的光电响应非线性效应进行了矫正。最后利用该测量系统对标称的λ/4波片、0.356λ波片、λ/2波片进行了相关实测并利用非线性最小二乘法对测量数据进行处理，获得了参考波长在632.8 nm的各波片的相位延迟量与快轴方位角。由该测量系统的实测结果可知：本文采用的拟合光强法测量λ/4波片、0.356λ波片延迟量的测量误差小于0.05°，测量精度比传统光强测量法高一个数量级以上。对于λ/2非消色差波片，在该测量系统下切换终端光强接受设备并采用光谱分析法对其进行测量，测得其延迟量误差小于0.02°，远小于拟合光强法的测量误差0.70°，克服了光强法无法精确测量波片延迟量为180°的缺陷。实测结果与模拟仿真相符。

A novel phase-shifted long-period fiber grating (PS-LPFG) for the simultaneous measurement of torsion and temperature is described and experimentally demonstrated. The PS-LPFG is fabricated by inserting a pre-twisted structure into the long-period fiber grating (LPFG) written in single-mode fiber (SMF). Experimental results show that the torsion sensitivities of the two dips are ?0.114 nm/(rad/m) and ?0.069 nm/(rad/m) in the clockwise direction, and ?0.087 nm/(rad/m) and ?0.048 nm/(rad/m) in the counterclockwise direction, respectively. The temperature sensitivities of the two dips are 0.057 nm/°C and 0.051 nm/°C, respectively. The two dips of the PS-LPFG exhibit different responses to torsion and temperature. Simultaneous measurement of torsion and temperature can be implemented using a sensor. The feasibility and stabilization of simultaneous torsion and temperature measurement have been confirmed, and hence this novel PS-LPFG demonstrates potential for fiber sensing and engineering applications.