Light Shaping with Holography, GPC and Holo-GPC

Light shaping techniques based on phase-only modulation offer multiple advantages over amplitude modulation. This review examines and compares the merits of two phase modulation techniques; phase-only computer generated holography and Generalized Phase Contrast (GPC). Both techniques are briefly presented while recent developments in GPC will also be covered. Furthermore, novel hybrid schemes that inherit merits from both holography and GPC are also covered. In particular, our most recent technique coined “Holo-GPC” will be discussed in addition to earlier hybrid techniques. We will discuss how Holo-GPC utilizes the simplicity of GPC in forming well-defined speckle-free shapes and the versatility of holography in distributing these shaped beams over an extended 3D volume. To conclude, we cite applications where the combined strengths of the two photon-efficient phase-only light shaping techniques open new possibilities.