Femtosecond and nanosecond laser polishing of rough polycrystalline diamond

The laser polishing of rough (roughness of 5 mu m) diamond plate using femtosecond and nanosecond pulses was realized for the first time. The effect of the angle of incidence, the number of passes, scanning speed, and laser fluence on the surface roughness was investigated and the optimal conditions were found. The initial roughness of the diamond plate was reduced by 5 times from 5 to 1 mu m for both femtosecond and nanosecond laser sources. The results indicate the prospects of laser polishing of rough polycrystalline diamond samples.