GPC: Recent developments

Generalized Phase Contrast (GPC) is an efficient method for generating specklefree contiguous optical distributions. It has been used in applications such as optical manipulation, microscopy, optical cryptography and more contemporary biological applications such as two-photon optogenetics or neurophotonics. Among its diverse applications, simple efficient shaped for illumination or excitation happens to have the biggest potential use beyond the research experiments. Hence, we preset recent GPC developments geared towards these applications. We start by presenting the theory needed for designing an optimized GPC light shaper (GPC LS). A compact GPC LS implementation based on this design is then used to demonstrate the GPC LS’s benefits on typical applications where lasers have to be shaped into a particular pattern. Both simulations and experiments show ~80% efficiency, ~3x intensity gain and ~90% energy savings. As an application example, we show how computer generated hologram reconstruction can be up to three times brighter or how the number of optical spots can be multiplied threefold while maintaining the brightness. Finally, to demonstrate its potential for biomedical multispectral applications, we demonstrate efficient light shaping of a supercontinuum laser over the visible wavelength range.