A Preliminary Exploration On The Non-destructive Structural Color Testing Method Of The Duty Cycle Of Grating

The diffraction efficiency of the multilayer dielectric grating in the fast ignition system restricts the performance of the system.Considering the uncertain factors to the graphic transfer in the grating fabrication process,the current lack of nondestructive testing means there are no effective and reliable methods for detection of the parame-ters of the grating.So,this thesis put forwards the nondestructive test method for the parameters of the grating based on the structural color analysis.1.The paper discusses the basic principle of the nondestructive test method for the parameters of the grating based on the structural color analysis.introduces the rigorous coupled wave to calculate the diffraction efficiency of the periodic structure,analyzes the method to generate the structural color with light source spectrum and the diffraction efficiency of grating,gives the specific steps and the code which used to calculte the efficiency.The calculation program considering the factors such as multidimensional periodic structure and the cone angle diffraction etc.2.The influence of the parameters(polarization and FWHM)of light source and the parameters of the grating on the structural color are analyzed.The parameters of the grating include the line density,the height of the grating,the duty cycle and the shape of the groove.The conclusion are showed as following:when the line density of the grating is 17401/mm the structural color is not sensitive with the small change of the line density.At the same time,the smaller change of the height of the grating could cause a change of the structural color at the grating height 300nm.3.The experiments of the experiments are illustrated in the microscope detect sys-tem and the spectrometer system with the multilayer dielectric grating at a line density 1740l/mm.The error is 13%?20%at the microscope detect system in duty cycle de-tection and the error is 3%?20%at the spectrometer system in duty cycle detection.The result of this thesis indicate that the structural color method based on the rig-orous coupled wave to detect the parameters of the grating is avaiable.However,it produces error and in the last part of thesis,the future direction and the improvement advice are given.