可用于大曲率半径自由曲面高精度检测的零位混合补偿干涉检测技术研究

There are a lot of advantages such as improving image quality of optical system, simplifying system structure and reducing system cost for freeform optical system. Freeform surface is the core component of the optical system in new generation. Freeform surface in high accuracy is the foundation of advanced optical system development and the surface error testing of freeform surface in high accuracy is the important frontiers and hotspots in advanced optical system developing. Aiming to solve the difficulty caused by testing path in a long distance which brings tough requirements to the size of testing site and testing environment in large radius of curvature freeform surface testing, we provided a hybrid compensation testing method combining CGH (computer generated hologram) and auxiliary lens. With the above method, the testing for freeform surface can be accomplished. The optical path can be shorten to less than 1/5 of the freeform surface curvature radius length and the testing accuracy can be better than PV λ/20(λ=632.8nm). A hybrid compensation optimization model will be established. With the designing of CGH auxiliary alignment regions, the optical components in the optical path will be aligned in high accuracy. By establishing the distortion correction model and error separation model, the testing map can be unified with the mirror coordinate, and the system error can also be removed from the freeform testing result. Contents of the project will lay a theoretical foundation and provide key technical support for the high-accuracy testing of more complex freeform surface in the future.

自由曲面具有改善光学系统像质、简化系统结构及降低系统成本等诸多优势，是新一代光学系统的核心部件。优异的面形精度是高性能自由曲面光学系统研制开发的基础，其面形质量的高精度检测是当前研究的前沿与热点问题。本课题针对大曲率半径自由曲面干涉检测中，由于检测光路尺寸长而对检测场地、检测环境要求苛刻造成检测难度高的问题，采用CGH（computer generated hologram，计算全息图）与辅助透镜相结合的混合补偿方法，将测试光路长度缩短至自由曲面曲率半径长度1/5以内，实现对自由曲面的零位补偿测量，检测精度优于PVλ/20（λ=632.8nm）。建立混合补偿光路参数优化模型，通过对CGH对准区域的设计，精确实现光路中各元件的对准；建立畸变校正模型与误差分离模型，完成检测结果与镜面物理坐标的统一，实现检测结果中系统误差的剔除。为今后更复杂自由曲面的高精度测试奠定理论基础、提供关键技术支撑。

自由曲面具有改善光学系统像质、简化系统结构及降低系统成本等诸多优势，是新一代光学系统的核心部件。本课题主要研究针对大口径长焦距自由曲面主镜的混合补偿测量方法，同时对其他大口径次镜的混合补偿方法进行了一定的研究。通过仿真与实验相结合的方式实现了对于大口径非球面次镜的检测，利用仿真理论实现了对于长焦距自由曲面主镜的混合补偿检测。为后续先进光学系统的开发研制提供了保障和技术支持。