Focusing light through random scattering media by four-element division algorithm

•A novel phase optimization approach to focus light through scattering media is proposed.•This approach aims to improve the converging speed and susceptibility.•The mechanism relies on constructive interference of all phase modulated elements.

The focusing of light through random scattering materials using wavefront shaping is studied in detail. We propose a newfangled approach namely four-element division algorithm to improve the average convergence rate and signal-to-noise ratio of focusing. Using 4096 independently controlled segments of light, the intensity at the target is 72 times enhanced over the original intensity at the same position. The four-element division algorithm and existing phase control algorithms of focusing through scattering media are compared by both of the numerical simulation and the experiment. It is found that four-element division algorithm is particularly advantageous to improve the average convergence rate of focusing.