在激光扫描大型三维曲面测量中, 激光光斑中心的准确定位是提高测量分辨力的关键。 当测距范围较大时, 受多种因素的影响, 激光光强分布严重不均致使其几何中心与强度中心发生了偏离。 此时, 传统的光斑中心提取方法不能适用。 为此, 根据光斑图像仍能给出圆形光斑的大部分轮廓这一特点, 提出了基于Hough变换的激光光斑中心读取方法。 实验结果表明该方法对提高大型三维曲面测量精度是有效的。

The precise location of the laser spot center is an important step to raise the measurement resolution in large 3-D surface profile measuring system of laser scanning. While measured distance is large, laser spot intensity distributes non-uniformly so that the deviation between the geometric center and the intensive center of the spot emerges because of the influence of various factors. The conventional methods of locating center of spot is unsuitable to the condition. According to the feature that the better part of circle spot can be obtained by the image of spot, a new method for locating the center of spot based on Hough transform (HT) is presented. The experimental results show that the method can effectively increase the measuring precision of large scale 3-D surface profile.