Comparison of varied-line-spacing plane grating and varied-line-spacing spherical grating monochromators for the Siam Photon Source

This work describes a design study of vacuum ultraviolet and soft X-ray monochromators of the first beamline for the Siam Photon Source. Two monochromators using varied-line-spacing plane gratings and varied-line-spacing spherical gratings in the constant-deviation-angle configuration has been designed and their performance has been evaluated. The effects of the figure slope error on the resolving power of the monochromators have been studied. The performance of both monochromators is compared.