Alignment method based on peak's sharpness degree of correlation coefficient profile of sid-view images for polarization maintaining fibers

The sid-vie-image methods are playing important roles in the location and alignment of birefringent axes of Polarization Maintaining (PM) fibers. However, due to be restricted by ligh-intensity distribution characteristics, almost all of the sid-vie-image methods were of low applicability. In order to improve the applicability of sid-vie-image methods, a new alignment algorithm based on the peak's sharpness degree of correlation coefficient profile was developed. Correlation coefficient profiles were acquired by calculating the correlation among ligh-intensity profiles, then the peak's sharpness degree of correlation coefficient profiles was denoted as characteristic value. Compared with traditional sid-vie-image methods, the novel method was not restricted by ligh-intensity characteristics, so it shows excellent applicability. To improve the precision of angle orientation, alignment accuracy was measured on different observation planes in a series of experiments and the observation position with high alignment precision was acquired. Finally, the alignment precision of these position was analyzed with the help of practical experiment. According to the experiment result, alignment accuracy better than 0.9 is achieved.