High-efficiency time-reversed ultrasonically encoded optical focusing using a large-area photorefractive polymer

Time-reversed ultrasonically encoded (TRUE) optical focusing focuses light beyond one transport mean free path by phase-conjugating the ultrasonically tagged light. However, in previous works, only a small portion of the tagged light was phase-conjugated by using a photorefractive Bi12SiO20 crystal, due to its small active area (1x1 cm2). In this work, we report high-efficiency TRUE focusing using a large-area photorefractive polymer (5x5 cm2), which demonstrated ~40 times increase in focused energy. Further, we imaged absorbers embedded in a turbid sample of thickness of ~12 transport mean free paths.

[1]  E. G. van Putten,et al.  Demixing light paths inside disordered metamaterials. , 2008, Optics express.

[2]  S. I. Stepanov,et al.  Efficient unstationary holographic recording in photorefractive crystals under an external alternating electric field , 1985 .

[3]  Puxiang Lai,et al.  Time-reversed ultrasonically encoded optical focusing into tissue-mimicking media with thickness up to 70 mean free paths. , 2011, Journal of biomedical optics.

[4]  P. Blanche,et al.  Holographic three-dimensional telepresence using large-area photorefractive polymer , 2010, Nature.

[5]  Puxiang Lai,et al.  Reflection-mode time-reversed ultrasonically encoded optical focusing into turbid media. , 2011, Journal of biomedical optics.

[6]  Ke Si,et al.  Fluorescence imaging beyond the ballistic regime by ultrasound pulse guided digital phase conjugation , 2012, Nature Photonics.

[7]  Ying Min Wang,et al.  Deep-tissue focal fluorescence imaging with digitally time-reversed ultrasound-encoded light , 2012, Nature Communications.

[8]  Robert A Norwood,et al.  Submillisecond response of a photorefractive polymer under single nanosecond pulse exposure , 2006 .

[9]  P. Blanche,et al.  An updatable holographic three-dimensional display , 2008, Nature.

[10]  Lihong V. Wang,et al.  Time-reversed ultrasonically encoded optical focusing into scattering media , 2010, Nature photonics.

[11]  N. Peyghambarian,et al.  A photorefractive polymer with high optical gain and diffraction efficiency near 100% , 1994, Nature.