155mm入射距离的XUV平场光谱仪参量设计

Parameters of XUV spectrometer with 155 mm incident distance

为了缩短掠入射XUV平场谱仪尺寸以方便其使用．利用建立的光路追踪程序优化研究了当入射距离缩短为155mm，聚焦面仍满足平面的条件下凹面光栅的各参量对谱线成像的影响。计算表明，对于曲率半径为5649mm、光栅标称间距为1／1200mm的凹面光栅，当入射距离为155mm，入射角为87．5°，聚焦参量为-21／R，彗差参量为4．655×10^2／R^2时，可以在12～40nm波段内得到优化的成像效果。

In order to make the grazing incidence XUV flat-field spectrograph＇s size shorter for the convenience of use, a ray-tracing code is set to research the influence of the concave grating＇s parameter on the spectrum imaging when the incident dis- tanee is 155 mm and the focusing surface is still flat. It is found that for the concave grating with curvature radius of 5 649 mm and 1/1 200 nm nominal spacing of the grooves, the angle of incidence is 87.5°, when the incident distance is 155 mm, the focus parameter is -21/R and the coma-type aberration parameter is 4. 655× 10^2/R^2 , a better imaging effect within the wave band of 12～40 nm is realized.