基于多波长点衍射干涉的高次非球面面形检测技术基础研究

High order asphere has become the key part in modern high-tech electro-optical system for its excellent optical characteristics and flexible parameters, thus leading to the urgent demand of its high accurate and efficient measurement. However, the relative measuring equipments produced by foreign countries are not for sale, at the same time, our own relative research is still insufficient. In this project, we present a novel measuring method which combine multiwavelength point diffraction interferometry with annular subaperture to achieve high accurate measurement of high order asphere. This research mainly focus on two aspects: one is theory and critical technologies of multiwavelength interferometry based on point diffraction theory; the other is theory and technologies on measuring high order asphere with annular subaperture based on multiwavelength point diffraction. Aiming at the problem that special compensator has to be produced in civil high order asphere measurement which leads to a long tesing period and accuracy limitation caused by compensator, we take a nearly idea spherical wavefront produced by the diffraction of mutiwavelength laser beams passing a pinhole in micron size as the reference wavefront which can achieve sub nanoscale precision theoretically. By the combination of mutiwavelength interferometry and annular subaperture in the meanwhile, the longitudinal measurable range of the measuring system can be expanded. By this means, no null compensator is required during the testing process which make the testing versatile and efficient. Our research presents a new way to measure high order asphere and lays theoretical and technical foundation for autonomously developing the corresponding high accurate measuring equipment.

高次非球面元件因具有更多的设计参数而具有更优异的光学特性，已成为现代高科技光电系统中的关键零件，对其面形的高精度高效率检测需求激增。而国外相关检测设备并不外售，国内研究不足。本项目提出基于多波长点衍射干涉结合环形子孔径拼接技术实现高次非球面高精度检测的新方法。主要研究基于小孔点衍射方法的多波长干涉测量理论与关键技术；基于多波长点衍射干涉的环形子孔径拼接检测高次非球面的理论和技术。该方法针对国内检测多需制作专用补偿器，检测周期长且检测精度受补偿镜制造精度限制的问题，以多个波长激光通过微米级小孔衍射产生大范围近乎理想的球面波作为干涉系统参考波面，理论上可以达到亚纳米级检测精度；而与环形子孔径拼接技术相结合则进一步扩大了测量系统的纵向测试范围，不需制造传统检测方法的零位补偿器，具有通用性和高效性。该方法为高次非球面的高精度检测开辟了新的途径，为我国相应检测设备的自主研制奠定理论和技术基础。

高次非球面元件因具有更多的设计参数而具有更优异的光学特性，已成为现代高科技光电系统中的关键零件，对其面形的高精度高效率检测需求激增。而国外相关检测设备并不外售，国内研究不足。本项目提出基于多波长点衍射干涉结合环形子孔径拼接技术实现高次非球面高精度检测的新方法。主要研究基于小孔点衍射方法的多波长干涉测量理论与关键技术；基于多波长点衍射干涉的环形子孔径拼接检测高次非球面的理论和技术。该方法针对国内检测多需制作专用补偿器，检测周期长且检测精度受补偿镜制造精度限制的问题，以多个波长激光通过微米级小孔衍射产生大范围近乎理想的球面波作为干涉系统参考波面，理论上可以达到亚纳米级检测精度；而与环形子孔径拼接技术相结合则进一步扩大了测量系统的纵向测试范围，不需制造传统检测方法的零位补偿器，具有通用性和高效性。该方法为高次非球面的高精度检测开辟了新的途径，为我国相应检测设备的自主研制奠定理论和技术基础。