Influence of mechanical deformation of splicing grating on far-field intensity

Currently, it’s difficult to manufacture large area grating and multiple smaller pieces of grating blocks splice large area gratings.The grating blocks will slightly in splicing process. This paper analyzes the splicing grating’s normal deformation characteristics, builds the theoretical model of deformation, and calculates and analyses the case of two grating blocks splicing. It is found the light field diffraction caused by a tiny deformation can not be ignores. The tolerance of grating mechanical measures to prevent deformation are discussed.