Theoretical And Experimental Study Of Mosaic Pulse-compression-grating

In order to achieve large-scale grating the theoretical and experimental study on the mosaic grating are present in this paper. The main contents are as follows:Firstly the significance of research on the Inertial Confinement Fusion and the current progress of the study on Pulse Compression Grating are introduced. The feasibility of tiling grating is analyzed.The far-field diffraction pattern influenced by the error of mosaic gratings and diffraction wave aberration is theoretically calculated. The parameter of mosaic grating is introduced, which are the piston-error tip-tilt error and wave aberration. Far-field intensity distribution functions and program of Matlab are used to simulate mosaic gratings which have the same parameters. It has proved that the transformation of far-field diffraction pattern is influenced by the tiling error. And the request of error accuracy also has been educed .The diffraction grating wave aberration impacts the far-field diffraction pattern. So it's characteristic and error accuracy of the mosaic gratings is analyzed when the two gratings have the same parameters. If the wave aberration is 0.5λ, the demand of the tiling precision is about 0.18d.In practice the mosaic error can not be measured directly, so the characteristic of moire fringe has been introduced to reveal the tiling error of the gratings. And the moire fringe's theory and the tiling error have been analyzed. In order to avoid the phenomenon of interference fringe moving, a fringe locking system is used to control the moire fringe. The phasic difference and the angle warp of moire fringe can achieve 0.1 stripe. The wobble of moire fringe is about 0.07 stripe. And the error of space frequency is about 0.1 stripe.The process and conclusion of the mosaic gratings experiment explains that the mosaic grating theory and project are feasible.