离轴非球面在细磨与粗抛阶段的波面再现检测方法

项目名称： 离轴非球面在细磨与粗抛阶段的波面再现检测方法

项目编号： No.11203049

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 天文学、地球科学

项目作者： 武中华

作者单位： 中国科学院国家天文台南京天文光学技术研究所

项目金额： 28万元

中文摘要： 离轴非球面在细磨及粗抛阶段的面形误差较大，超出了普通干涉仪检测的范围。和红外干涉仪及轮廓仪相比，付科法有着不可替代的优势，仍然被广泛使用。但是利用传统付科法检验离轴非球面也有局限性：不能定量；面形判断需上下与左右切割弥散斑，严重依赖使用者的经验。针对其缺陷，提出了基于付科法的离轴非球面在细磨及粗抛阶段的波面再现定量检测方法。该方法将刀口仪、图像采集处理系统及数据处理软件三者有机结合，从阴影图灰度变化中抽象出数学模型，然后利用该模型进行数据处理得到被检镜面的面形误差数据，从而将付科检测得到的阴影图转换成面形轮廓图，实现付科法定量检验离轴非球面。创建的数学模型拓展了以往付科定量的检测范围，以适用于细磨及粗抛阶段大误差值的离轴非球面检验，且能够与精抛阶段的干涉仪检测相衔接。该方法直观准确，可以大大改善离轴非球面的面形误差收敛速度、降低高频误差、提高面形精度，力求实现在细磨及粗抛阶段检测的突破。

中文关键词： 离轴非球面；光学检测；付科法；波面再现；定量分析

英文摘要： Surface error of off-axis aspherics in the stage of grinding and pre-polishing is too large to test by common interferometer. Comparing with infrared interferometer and profiler, Foucault test has irreplacable advantages, and is used widely. However, convetional Foucault has its disadvantages to test off-axis aspheric surface: it is not quantitative; the judgement of surface needs up-to-down and left-to-right cut the image of source, and depand on experience of the users. According to its disadvantanges, wavefront retrieval based on Foucault test is proposed to test aspherical surface in the stage of grinding and pre-polishing. The method integrates conventional Foucault test with image collecting and processing system and data processing software. Firstly, mathematical model is abstracted from shadow variation. Secondly, data of surface error would be acquired through data processing of theoretical model. Hence that shadow pattern by conventional Foucault test is convirted to surface error contour, and quantitative test by Foucault test is achieved. The mathematical model gives greater scope than Foucault quantitative test ever before to be applicable for large scale error of off-axis aspherac surface in the stage of grinding and pre-polishing, meanwhile, it is consitent with surface error by interferometer te

英文关键词： Off-axis aspherics；Optical test；Foucault test；Wavefront retrieval；Quantitative analysis