Ultrasonically encoded wavefront shaping for focusing into random media

• DOI: 10.1038/srep03918
• Publication Date: 2014-01-29T10:01:55Z
• Authors: Jian Wei Tay; Puxiang Lai; Yuta Suzuki; Lihong V. Wang
• Keywords: SIGNAL (programming language); Spatial light modulator; Optical path

Phase distortions due to scattering in random media restrict optical focusing beyond one transport mean free path. However, can be compensated for by applying a correction the illumination wavefront using spatial light modulators. One method of obtaining is iterative determination an optimization algorithm. In past, feedback signal required either direct access target region, or invasive embedding molecular probes within media. Here, we propose ultrasonically encoded as guide dynamically and non-invasively. our proof-of-principle demonstration, diffuse was refocused ultrasound focal zone, with focus-to-background ratio more than order magnitude after 600 iterations. With further improvements, especially speed, proposed should find broad applications deep tissue imaging therapy.