白光干涉自动测量砂轮表面时干涉区间的确定

摘要

用白光干涉仪自动测量金刚石砂轮表面形貌时，为了获得更精准的干涉区域，在干涉仪所采集到的一系列图像中，首先通过计算相邻的2张图像各像素灰度值的变化从而得到一系列新的灰度图像。然后计算每帧新图像的非零点像素的均值和极值，据此计算得出用于确定干涉区域的阈值以实现自动扫描。实验表明：此方法运算速度较快，而且对局部区域的干涉更敏感，可以更精确地搜索出干涉区间。采用步进电机和压电陶瓷二级驱动，可以在100 s内实现100μm 范围内扫描区间的自动获取并实现垂直方向的数据采集。%In order to improve the effectiveness in white light interferometer ( WLI) for diamond grinding wheels topography measurement,first,the intensity change of each pixel among two adjacent images in the series of images captured by the WLI was calculated to get a new series of grayscale images.A threshold was obtained by calculating the mean and the extreme value of non-zero pixels of each new image.According to this threshold,the interference area could be found to realize the automatic scanning. Experiments show that it is more sensitive to local interference area and can get a more accurate interference range at a fast rate u-sing this algorithm.Adopting the stepper motor and piezoelectric ceramic transducer,an automatic scanning and vertical sampling within the range of 100 μm can be completed in 100 seconds.