中阶梯光栅刻划误差要求分析

Analysis of the Ruling Error Requirements for Echelle Grating

中阶梯光栅作为高色散和高分辨率光学器件,已经广泛的应用于大型光谱仪器之中。在中阶梯光栅的刻划过程中,存在刻划误差,这将严重影响光栅衍射性能,最终使得衍射效果产生缺陷。针对此情况,定量分析了中阶梯光栅的刻划误差对衍射光谱、衍射级次、波前误差、鬼线强度、杂散光强度的影响以及提出了一种从衍射效率角度分析刻划误差的方法。在满足一定条件下,求得上述因素对应的刻划误差分别为:1 265.8 nm、352 nm、37 nm、112 nm、3.4 nm。这对光栅刻划时限定刻划机的刻划精度提供了直接和重要的参考。

Echelle grating is used extensively in spectral instruments owing to its advantages, such as the advanced intrinsic dispersion and resolving power. But while ruling the echelle grating, there may be some periodic components of spacing errors which will seriously affect the performance of grating diffraction and lead to defects of the diffraction effects. In response to this situation, the effect of grating＇s line error on diffraction spectrum, diffraction order, wavefront error, the intensity of the rowland ghost line and the intensity of stray light was proposed. What＇s more, a method for analyzing the grating＇s line error from the aspect of the diffraction efficiency was proposed. Under certain conditions, the ruling errors for meeting every kind of requests are l 265.8 nm, 352 nm, 37 nm, 112 nm, 3.4 nm respectively, which provides a direct and important reference fbr the ruling accuracy before ruling an echelle grating.