Study On Factors Of Resolution And Detection Technology For Variable Included Angle Plane Grating Monochromator

Synchrotron radiation plays an important role in many fields of sciences.Synchrotron radiation’s beam line is an important part of a device. Andmonochromator is the core device of beam line, which is used to select a certainwavelength range of monochromatic light. In the soft X-ray beam line, VariableAngle Plane Grating Monochromators is widely used with wide spectrum and highresolution. But with the development of applications on synchrotron radiation, thehigher resolution of monochromatic light to complete the relevant experimental whatis need to make. Therefore, it’s very important to improve the energy resolution ofvariable-included angle plane grating monochromator of synchrotron radiation.This paper is around the soft X-ray spectroscopy and microscopy beam line’svariable included angle plane grating monochromator of shanghai Synchrotronradiation Facility. In order to improve the resolution of Variable Angle Plane Gratingmonochromator, the main factors of influencing the resolution of monochromator arestudied. The following aspects are studied in detail.1. Focus constant is unique characteristic parameters of variable included angleplane grating monochromator, and it also is the imaging condition factor to decidethe diffraction grating. The value of focus constant is directly determining the valueof the resolution. Get the relationship of focusing constant and energy resolution by theoretical derivation. According to the relationship, we can make a reasonable valueof focus constant to improve the resolution of the monochromator.2. As the third generation synchrotron radiation substantially increase thebrightness to make the optical elements’ surface to be subjected to more heat loadthan before. That will make the surface of the optical elements thermal deformationand decrease the resolution of monochromator. Use finite element analysis softwareto do thermo-mechanical analysis for optical elements. The thermal deformations ofoptical elements’ surface were calculated by software. The decline of themonochromator’s resolution was calculated by both function and software. Then, theresolution of monochromator was improved by optimizing focus constant. Finally,use the ray-tracing software to tracing the optical path, and evaluate the method.3. The surface of optics in the monochromator will produce carbon pollution tolead it doesn’t work. So the damaged optical needed to replace. Whether the opticalelement can accurately reset spatial position or not was determined the value ofresolution monochromator. Therefore, the recovery methods for detecting spatialposition of optics were proposed to ensure the resolution of the monochromator isnot affected.The research contents of this paper provides theoretical basis for improving theresolution of variable included angle plane grating monochromator and the testingmethods of reset the replaced optics’ spatial position.