Precise location for optical fiber surface with sampling restraint Hough transformation

In order to improve the direction stability of light beam from optical fiber, a novel location method for optical fiber surface was proposed. The energy distribution at optical fiber surface was analyzed and Hough transformation with sampling restraint was proposed in this method to eliminate noise and obtain the contour points according to the contour character. The points divided into two classes (primitive class and noise class) were respectively transformed into parameter space to reduce memory and restrain noise to obtain the contour points. The points were set different weight for their different effect on the center of the contour in fitting process. The experimental results show that the uncertainty is less than 0.2 pixel (less than 0.4 μm) when the proposed method is used to locate optical fiber surface and a ten-fold image lens is used.