Momentum selection for enhanced adaptive focusing through semi-transparent media

• DOI: 10.48550/arxiv.1506.06886
• Publication Date: 2015-01-01
• Authors: Diego Di Battista; Giannis Zacharakis; Marco Leonetti
• Keywords: Opacity; Optical path

Adaptive optics can focus light through opaque media by compensating the random phase delay acquired while crossing a scattering curtain. The technique is commonly exploited in many fields, including astrophysics, microscopy, biomedicine and biology. A turbid lens has capability of producing foci with resolution higher than conventional optics, however it fundamental limit: to obtain sharp one introduce strongly medium optical path. Indeed tight focusing needs strong and, as consequence, high obtained only for weakly transmitting samples. Here we disclose an unprecedented phenomenon which allows highly concentrated spots even introducing minimum amount beam path that semi-transparent materials. By filtering pseudo-ballistic components transmitted are able experimentally overcome limits adaptive resolution, gathering on spot diameter third original speckle grain.