Single-shot generation of composite optical vortex beams using hybrid binary fork gratings.

We design and experimentally demonstrate a simple, single-shot method for the generation of arbitrary composite vortex (CV) beams using hybrid binary fork gratings (hBFG). These gratings were computationally generated by removing the central region around the fork-dislocation of azimuthal charge ℓ and substituting it with a BFG of a different charge ℓ. The geometrical parameters of hBFGs were optimized for the efficient generation of CV beams. The method was further extended to the generation of CV beams consisting of three different ℓ and of higher radial charges p. This simple generation method may be useful to generate complex beam shapes with engineered phase fronts without complicated interferometry based techniques.