基于电光补偿测量的光相位延迟拓展测量法

在激光电光调制补偿测量光相位延迟量过程中,加入交流调制电压形成倍频接收信号,获得消光的精确定位,能提高测量精确度。通过调制信号形状变化与相关参量之依赖关系,可拓展测量范围,解决在某些点附近无法测量波片相位的"盲区"问题。根据接收到的调制光信号形状变化趋势与待测波片样品方位、延迟量、旋转方向等条件的联系,在待测波片快轴选定后,通过波片旋转影响信号形状变化规律的观测,可敏锐地甄别在半波点或全波长点附近波片的正负偏差特性,从而解决了一般偏振干涉补偿测量相位无法解决的测量盲区问题。不改变测量系统结构也不需添加任何器件,适应于最小延迟偏差≥λ/360的情况。

Optical phase delay expansion measuring method based on electro-optical compensation measurement

In the process of measuring the optical phase delay with the laser electro-optical modulation compensation, the precise extinction position is obtained and the measurement accuracy is improved when the frequency multiplication is formed by adding AC voltage modulation.The measurement range is expanded and wave-plate phase "blind spot" problem at some points is resolved by use of the relationship between the signal shape variation and correlation parameters.According to the received optical signal modulation shape change trend and the azimuth, retardation, rotational direction, and other measurement conditions of the measured wave plate, fast axis of the measured wave plate is selected.The positive and negative deviation characteristic near the half wave-plate or the full wave-plate is keenly identified.So the technology of the polarization interference compensation measurement is solved.The method does not change the system structure nor to add any device, and has no effect on the accuracy of the system.The method also can be applied to the delay deviation which is greater than λ/360.