针对当前陷波滤光片设计方法中,因需要大量薄层和折射率连续渐变而导致的制作难度较高的问题,介绍了一种陷波滤光片的类褶皱膜系设计方法。此方法中,每层薄膜的层内折射率不变,层间折射率呈离散型渐变,每层为1个光学厚度,膜系模拟计算的光谱很好,并可降低制造工艺难度。给出了膜系的基本结构形式,并分析了其中各参数对陷波滤光片光谱的影响,指出了参数变化对光谱影响的基本规律。通过对典型膜系设计,模拟分析了膜厚偏差和折射率偏差对光谱的影响。结果表明,膜系对膜厚偏差更加敏感,为膜系镀制工艺中的误差控制提供了理论依据。

As the current design methods of notch filter will lead to high fabrication difficulty because of the needs of many thin layers and the continuous gradient of refractive index, a quasi-rugate design method of notch filter is introduced and described. In this method, the refractive index remains the same in each layer and changes with layers discretely. Each layer is 1 optical depth and spectral simulation result is good while the technical difficulty is reduced. The coating structures are presented, the influences of different parameters to spectral properties are analyzed, and the basic rules of spectral changes with these parameters are also provided. Through the design of a typical coating structure, the effects of physical thickness and refractive index on the spectrum are simulated and analyzed. The results show that the physical thickness errors is the key sensitive factor to films and this provides the theoretical guidance of error control for the coating process.