By the use of the jones matrix of wave plates , the common measurement formula of wave plates was introduced , and a novel method based on phase shifting was proposed to measure the phase retardation for many kinds of wave plates 在波片测量时，无需被测波片的光轴和补偿片的光轴成45要求，即不必知道波片的具体快慢光轴方位，只要将波片平行放入。
Utilizing the principle of the smoothshaft to open 0 . 4 mm crankshaft to the width of crack : ( 1 ) when it compares with one position crack , crankshaft natural frequency as crack depth than increase and reducing constantly 利用光轴的原理对裂纹宽度为0 . 4mm的曲轴进行研究得出： ( 1 )裂纹同一位置比时，曲轴固有频率随着裂纹深度比的增大而不断减小。
Furthermore , one - dimensional period isotropic gratings is discussed as degenerated case . based on this , the method is successfully generalized to analyze two - dimensional period anisotropic gratings and its degenerative case 在此基础上，将该方法成功地推广到任意面形、任意入射条件、任意光轴取向的二维各向异性周期光栅及其退化情形边行分析。
