Comparison of efficiency of bimorph mirror and spatial light modulator for laser beam focusing through a moderately scattering medium

Increasing of the focusing efficiency of partially coherent laser radiation propagated through a scattering medium was investigated. To improve focusing of scattered laser beam, we applied bimorph deformable mirror with 48 control electrodes and LCOS-SLM with 1920x1080 pixels resolution and compared their efficiencies. We used 5 mm thick glass cuvette filled with the suspension of 1 um polystyrene microspheres, diluted in distilled water. The concentration of scatterers were varied from 10(5) to 10(6) mm(-3). According to principle of similarity a medium with such parameters can be considered as an equivalent to the middle-density fog layer with the length ranging from 300 meters up to 5 kilometers. Numerical and experimental investigation of the focusing improvement showed that it is possible to increase the peak intensity of the focal spot up to 60 %.