像面散斑平均尺寸对散斑干涉条纹图的影响

Effect of average speckle size on speckle interference fringe pattern

散斑计量中,为了在动态测量中得到清晰的原始散斑条纹图,使更有效的提取相位信息,提出一种改变像面散斑平均尺寸大小对散斑成像影响的方法,进而改善原始散斑条纹图的清晰度。通过分析光路参数F数和放大倍数与像面散斑尺寸大小的定量关系,通过实验进行了验证。实验结果表明,形变量一定,系统放大倍数为1,成像透镜F值为4.5,或者,当F数为2,系统放大倍数为3.5,像面散斑平均尺寸大小为5.841μm,最接近像面尺寸5.86μm成像效果最好,经正余弦算法滤波后,得到的散斑条纹图最清晰,证实了像面上散斑尺寸大小对散斑条纹图的影响。

In speckle metrology,in order to obtain clear original speckle fringe in dynamic measurement and extract phase information more effectively,a method is proposed to change the influence of the average speckle size on the speckle imaging of the image surface,so as to improve the clarity of the original speckle fringe.By analyzing the quantitative relationship between the optical path system parameters F number and magnification factor and the speckle size of the image surface,the experiment was carried out to verify the factor.The results show that when the shape variable is fixed,the magnification of the system is 1 and the F value is 4.5,or,when F number is 2 and magnification is 3.5,the average size is 5.841μm,and the imaging effect is the best when it is closest to the size of 5.86μm.After filtering by the sine and cosine algorithm,the speckle fringe is the clearest.The effect of speckle size on speckle fringe pattern on image surface was confirmed.