石英玻璃光学均匀性测量范围扩展技术的研究

Study on extended technology of measurement range on the homogeneity of quartz glass

论述了用激光干涉仪测量石英玻璃光学均匀性时测量范围扩展的问题。通过理论研究和实际测量,完成了用180mm孔径干涉仪测量300mm孔径石英玻璃光学均匀性这一目标,为实现用300mm孔径干涉仪测量直径500mm石英玻璃的光学均匀性测量问题奠定了理论与实践的基础。实验通过建立光学均匀性测量范围扩展的数学模型,采用最小二乘法误差消除方法,每步波面分别计算,最后四步合成。创新性地设计了移动测量载物调整装置,实现了高精度多维调整。采用8个子孔径就3块圆形玻璃进行了测试,就拼接测量结果与直接全口径测量结果进行了对标,其拼接波面的均匀性绝对误差平均值分别为0.13×10-5、0.14×10-5、0.03×10-6。

The content that how to extend the measurement scope of quartz glass's homogeneity using laser interferometer is introduced.The aim is first realized that to measure quartz glass's homogeneity of 300mm by using 180mm interferometer through theoretical research and actual measurement.The foundation about how to measure homogeneity of 500mm quartz glasses by using 300mm interferometer is established in theory and practice.The mathematical model about extending the measurement scope of homogeneity is established in the experiment.The lest square method to eliminate errors is adopted.Every wave surface is calculated separately and synthesized by four steps.The adjusting device which can bear the weight is designed and adjusting many dimensions and high precision is realized.The three circle glasses are tested by eight sub-apertures,contrasting the synthesized result with the directive measurement result,finally the average absolute values of the homogeneity errors of the stitch wave surfaces are 0.13×10-5、0.14×10-5 and 0.03×10-6.