数字散斑剪切干涉光学测距

Optical Distance Sensing Using Digital Speckle Shearing Interferometry Technique

提出数字散斑剪切干涉测量原理。结合干涉条纹细锐化技术 ,在计算机上对散斑数据帧进行处理得到细锐化条纹图形 ,从图形中得到条纹周期 ,根据周期计算出被测目标距离。测量的范围可以随着光源的位移进行调节。实验结果表明 ,当平面漫反射物体距扩束透镜 5 6 .5 mm时 ,该法测得距离为 5 6 .9m m,有 0 .71%的偏差。当光源位移 5 0 mm时 ,该法测得的距离为 5 6 9.3mm,与尺子测得的距离 5 6 5 mm相差 0 .80 %。当距离达 10 0 0 m m时 ,难以测定条纹周期。该方法特别适用于对漫反射物体距离的测量 。

A novel theoretical model for sensing distance using digital speckle shearing interferometry (DSSI)is presented. The objective distance could be determined according to the relation between fringe period and distance. The fringe period could be determined from the sharpening fringe pictures which are processed using computer. In the experiment, when the distance between the objective and the expander lens was 56 5 mm,we had 56 9 mm of measurement by DSSI, with 0 71% deviation. When the light source had 50 mm displacement, the target distance was 569 3 mm measured by DSSI, with 0 80% deviation compared to the distance of 565mm measured with ruler.When the target distance is 1 000 mm, it is hard to determine fringe period.This method is suited for the determination of distance of diffuse targets, and has relatively insensitive towards environment.