为提高透射光栅谱仪对激光等离子体X光源的收集效率和光谱分辩率,研制了高效高分辨率大面积透射光栅光谱仪。该谱仪由轮胎镜、无支撑高线密度光栅和软X光CCD相机组成。应用部分相干光衍射理论,研究了该谱仪成像面上的光强分布和光谱分辩率,在1.4～12 nm的摄谱范围内光谱的分辨率为0.05 nm,与实验符合得很好。由于其高效率,该谱仪尤其适用于超短飞秒脉冲激光产生等离子体的实验研究。

A newly developed high efficiency high resolution,large size transmission grating spectrograph for higher collection efficiency and higher spectral resolution used in laser produced plasma diagnosis is reported.The spectrograph comprises of a toroidal mirror as the collecting optics,a standing-free high-density transmission grating and a soft X-ray CCD camera.The partial coherent light diffraction theory is applied to determine the X-ray intensity distribution on the soft X-ray CCD camera.Analysis shows that the spectral resolution is better than 0.05 nm over the spectral range of 1.4～12 nm,which is successfully demonstrated in the relevant experiments.Owing to its high efficiency,it is especially suitable for the experiments of ultrashort femtosecond pulse laser produced plasmas.