全息凹面光栅二阶圆场和平场成象特性

Second order circular and flat field imaging properties of holographically concave gratings

从全息凹面光栅几何成象理论出发，用简捷的解析方法研究固定入射狭缝全息凹面衍射光栅摄谱装架二阶圆场和平场成象特性。指出罗兰圆是唯一的二阶子午无离焦圆场摄谱装架和只存在唯一的一簇二阶弧矢无象散平场摄谱装架。还指出仅当柱面或平面光栅时，才能形成二阶子午无离焦平场和弧矢无象散圆场谱面。进一步讨论获得既不离焦也无象散的圆场和平场装架的可能性。

From the viewpoint of the geometrical imaging theory,the second order circular and flat field imaging properties of holographically concave diffraction grating spectrographs with a fixed entrance slit and the circular or flat field image are investigated by use of a straightforward analytics.It is shown that the Rowland mount is the only second order meridional focusing circular field spectrograph mount and that there exists the only set of second order sagittal anastigmatic flat field spectrograph mounts.It is also shown that only when the gratings are cylinder or plane ones,the second order sagittal anastigmatic circular field and meridional non defocus flat field spectral images can be formed.Furthermore,the possibilities for yielding both non defocus and anastigmatism circular and flat field mounts are discussed.