Analysis of light spot transversal transfer for the variable included angle plane grating monochormator at SSRF

In this paper,optical layout and structure of the variable included angle plane grating monochormator(VAPGM) at Shanghai Synchrotron Radiation Facility(SSRF) is introduced,and the factors that result in light spot transversal transfer are analyzed.Numerical simulation for the deformation under loads is done by using the Ansys code,and the dispensatory errors for relevant parts of the monochromator are decided based on the simulation results.The monochromator structure has been designed according to the dispensatory errors.After installation,the monochromator,was tested,and the transversal angle transfer repeatability was 0.7″.