title: Imaging-based amplitude laser beam shaping for material processing by 2D reflectivity tuning of a spatial light modulator.
abstract: We have demonstrated an imaging-based amplitude laser-beam-shaping technique for material processing by 2D reflectivity tuning of a spatial light modulator. Intensity masks with 256 gray levels were designed to shape the input laser beam in the outline profile and inside intensity distribution. Squared and circular flattop beam shapes were obtained at the diffractive near-field and then reconstructed at an image plane of an f-theta lens (f∼100  mm). The observed intensity distribution inside the beam-shaping geometry was much more even than using binary masks. The ablation footprint well matches the desired beam shape.
authors.forename: Jiangning
authors.initials: J
authors.lastname: Li
authors.forename: Zheng
authors.initials: Z
authors.lastname: Kuang
authors.forename: Stuart
authors.initials: S
authors.lastname: Edwardson
authors.forename: Walter
authors.initials: W
authors.lastname: Perrie
authors.forename: Dun
authors.initials: D
authors.lastname: Liu
authors.forename: Geoff
authors.initials: G
authors.lastname: Dearden