刻划光栅衍射波前及分辨本领的在线监测与智能决策

As the core dispersion element of spectral instruments, high-precision diffraction grating plays an important role in the progress and development of China's scientific research, national defense security, economic construction and social livelihood. In view of the problem that the current grating engraving state cannot be monitored online, which leads to the low efficiency and success rate of grating engraving, this subject innovatively proposes an online monitoring and intelligent decision-making method of grating diffraction front and resolution power model by indirect measurement of grating engraving error. Firstly, by exploring the sources of error affecting the grating diffraction wavefront, revealing the error generation mechanism, and constructing the measurement optical path to achieve simultaneous measurement of multiple errors; Secondly, the active knives technique is used to correct the reticle error in real time. Based on the trajectory coordinates of the reticle residual space and the error of the grating base layer, the FFT fast analysis algorithm is used to establish the grating diffraction wavefront fast reconstruction model with high frequency error information； Thirdly, based on the model and Huygens principle, the online construction method of grating resolution is explored. Finally, the grating diffraction wavefront and the resolution online monitoring and intelligent decision-making platform are built to realize the on-line monitoring of the grating performance index. The research results can significantly improve the grating ruling efficiency and success rate, and provide basic theoretical and technical guarantee for the development of grating spectrometer industry in China.

高精度衍射光栅作为光谱仪器的核心色散元件，对我国科学研究、国防安全、经济建设和社会民生等领域的进步和发展具有重要作用。针对目前光栅刻划状态无法在线监测，导致光栅刻划效率及成功率低的问题，本课题创新性的提出了通过间接测量光栅刻线误差，实现光栅衍射波前及分辨本领模型在线监测及智能决策方法。首先，通过探索影响光栅衍射波前误差来源，揭示误差产生机理，并搭建测量光路实现多误差量的同时测量；其次，利用主动控刀技术实时修正刻线误差，基于刻线残差空间轨迹坐标及光栅基底膜层误差，借助于FFT快速分析算法，建立具有高频误差信息的光栅衍射波前快速重构模型；再次，基于该模型及Huygens原理，探索光栅分辨本领的在线构建方法；最后搭建光栅衍射波前及分辨本领在线监测及智能决策平台，实现光栅性能指标的在线监测。该研究成果可显著提高光栅刻划效率及成功率，为我国光栅光谱仪器产业的发展提供基础理论及技术保障。

光栅是一种具有周期性空间结构的光学元件，可以将入射光波按光谱的波长顺序在空间上分离，从而被广泛用于光谱仪器中。近年来，随着光谱仪器在各行业的飞速发展，尤其以中阶梯光栅光谱仪为代表的高端光谱仪器，欧、美等国家的研究异常活跃，各大学、研究所和企业都纷纷加入其中，旨在不断开拓新的应用领域。对中阶梯光栅而言，目前只能通过刻划的方式进行加工，制作难度大，价格在普通光栅的几十倍以上。正是由于关键核心光学元件的制约，导致我国自主研发高端光谱仪器的步伐缓慢，部分仍需依赖进口。因此，提高光栅刻划机的刻划精度及刻划成功率，可以有效提高衍射光栅制作能力，加快我国光谱仪器的发展速度。.本课题针对光栅制作过程周期长，监测性能差导致光栅刻划成功率低、刻划质量无法控制这一问题，通过分析影响光栅刻划质量的误差因素，建立具有高频误差信息的全口径光栅衍射波前模型，以此在线反演光栅实时的刻划质量；提出了光栅刻刀主动控制技术，基于测量光路获取的光栅刻划误差，结合光栅基底面型误差，通过压电陶瓷驱动金刚石刻刀对误差进行实时补偿；结合补偿后误差构建的衍射波前，基于瑞利判据，构建利用等强度谱线宽度对比法求解的光栅分辨本领理论模型，构建实时显示评估光栅波前质量、分辨本领的系统，实现光栅刻划机控制系统参数同步修正，建立了光栅性能实时监测及智能预警模型，为高精度高质量衍射光栅的研制提供基础保障。