为解决视觉测量中重建强反射表面时遇到的过度曝光或曝光不足的问题,提出了一种基于自动多次曝光的面结构光测量方法。该方法的核心是根据基准点像素值随曝光时间的变化计算相机响应曲线。利用相机响应曲线和不同曝光时间下的图像计算出当前场景测量所需的曝光次数和曝光时间。将具有不同曝光时间的图像序列融合成新的条纹图像序列进行重建。实验结果表明:所提方法能够准确计算每次曝光的时间,克服了强反射表面引起的条纹图像饱和或过暗的问题,能够实现高动态范围表面反射率物体的三维形貌光学非接触测量。

In order to solve the problems of overexposure or underexposure that are easily encountered when reconstructing a strong reflective surface in visual measurement, we propose an automatic multiple exposure surface structure light measurement method. The core of this method is to calculate the camera response curve according to the variation of the reference point pixel value with the exposure time. Using camera response curves and images at different exposure time, we calculate the numbers of exposure and exposure time required for the current scene measurement. Image sequences with different exposure time are fused into a new fringe image sequence for reconstruction. The experimental results show that the method can accurately calculate the time of each exposure and overcome the problem of saturation or oversaturation of the fringe image caused by the strong reflection surface, and realize the three-dimensional optical non-contact measurement of the object with high dynamic range surface reflectivity.