子孔径光学检测拼接准确度实验研究

实验研究了子孔径光学检测的拼接准确度.实验选取9个子孔径进行拼接,同时利用ZYGO干涉仪来测量子孔径和整个被检面的表面面形.实验发现,测量基准子孔径和整个被检面的时间间隔对子孔径拼接准确度的评价存在严重影响.为此,重点研究了产生影响的原因并提出了消除测量基准子孔径和整个被测面时间间隙影响的方法.最后,利用该方法研究了子孔径重叠面积对拼接准确度的影响.结果显示,当重叠面积比为7%时,PV和RMS的拼接误差分别为0.03λ(λ=632.8 nm) 和 0.01λ,并且重叠面积比和拼接准确度呈近似线性关系.

Investigation of the Connection Accuracy of the Sub-aperture Optical Testing with Experiment

The connection accuracy of the sub-aperture optical testing is investigated with the experiment.9 sub-apertures are selected to reconstruct the whole surface and a ZYGO interferometer is used to measure the sub-aperture and the whole surface.The experimental results show that the time delay between measuring the whole surface and the standard sub-aperture affects the connection accuracy importantly.A method is given to eliminate the effect of the delay which is produced while measuring the standard sub-aperture and the whole surface.Then,we discuss the effect of the overlapping area on the connection accuracy with this method.The connection error of peak to valley (PV) and root mean square (rms) are 0.03λ(λ=632.8 nm) and 0.01λ while the ratio of overlapping area to the sub-aperture area the overlap area is 7%.And the ratio is approximately linear to the connection accuracy.