Experimental study of direct writing of metal reflective gratings with femtosecond laser

We propose a method to produce reflective gratings on a metal surface by using a focused near-IR 800 nm femtosecond laser beam.Through the experiments,the relationships between the diffraction efficiency of the gratings and the experimental parameters such as the laser scribing speed,the laser power and the grating period are studied.The first-order diffraction efficiency of the reflective grating that we have made on a nickel surface reaches as high as 7.47%.