Engineering the size of dark core of an optical vortex

An optical vortex is a light beam having a helical wavefront and a zero intensity region, a dark core, in the centre when viewed in the direction of the propagation of light beam. They can be created using computer generated holographic technique. We have studied the effect of the resolution of the computer generated hologram on the intensity profile of the vortex beam. The simulation results as well as the experimental results were in good agreement. We also give the significance of the obtained result for future research in this field. (C) 2009 Elsevier Ltd. All rights reserved.