Diffractive patterning on Cr thin film using femtosecond laser pulses

펨토초 레이저에 의한 크롬박막 미세 회절패턴 제작

In this paper, we suggested the femtosecond laser processing using the mask which makes Gaussian spatial beam distribution to a normalized distribution by Fresenel diffraction. Holography pattern of the size of $320{\times}320{\mu}m^2$ on the Cr thin film on glass substrate with a pixel size of $5{\times}5{\mu}m^2$ was fabricated according to the pattern generated by the iterative Fourier transform algorithm(IFTA) algorithm. We analysed the damage threshold with an assumption the power distribution as Gaussian profile as 45 $mJ/cm^2$. The regenerated image of letters through the diffractive pattern was well recognized at the screen.