为了降低紫外高分辨率罗兰光栅的像散对光谱像高展宽的影响, 提出了在罗兰圆上使用球面波非对称曝光设计思路。 推导完全校正离焦和子午彗差的表达式, 讨论了多种罗兰光栅记录结构的局限性, 优选适合校正紫外高分辨率罗兰光栅的优化方法。 通过全息光栅像面展宽表达式, 指出像散和弧矢彗差是影响光谱像高的主要因素, 并分配了两者的优化权重。 利用这种优化思路, 设计了工作波段110～200 nm紫外高分辨率罗兰光栅, 同时对比分析了传统光栅的像差系数和像高变化规律、 像面结构和光谱分辨率。 结果表明, 和传统罗兰光栅分辨率处于同一数量级的情况下, 所设计光栅光谱像高由25 mm降低到1.5 mm, 谱面能量集中度有显著的提高。

To correct astigmatism of UV high-resolution Rowland grating for influencing the image height broaden, a train of thought is proposed, which is based on an asymmetric exposure ofthe spherical wave at the Rowland circle. First of all, applying Rowland grating’ｓ aberration expressions derive the defocus and meridian coma full corrected equations. From these equations, a variety of limitations of Rowland grating record structure is discussed, which proves to be a suitable method for the optimization of UV high-resolution Rowland grating. Then, by the vertical ray deviation’s expression in the image plane, the paper refer to the astigmatism and sagittal coma as the principal factor to spectrum image-height, which is allocated the weight of aberration coefficients distribution. Taking advantage of this optimization thought, the waveband 110～200 nm, UV high-resolution Rowland grating is design. Meanwhile a series of contrastive analysis for the traditional grating and astigmatism correction Rowland grating, such as the variation tendency of aberration coefficients and spectrum image-height, image structure and spectral resolution. The results indicate, that in the same order of the spectral resolution, astigmatism correction Rowland grating spectral’ｓimage-height isreduced by 25 to 1.5 mm, spectrum energy is more concentrated.