Guidestar-assisted wavefront-shaping methods for focusing light into biological tissue
In the field of biomedical optics, optical scattering has traditionally limited the range of imaging within tissue to a depth of one millimetre. A recently developed class of wavefront-shaping techniques now aims to overcome this limit and achieve diffraction-limited control of light beyond one centimetre. By manipulating the spatial profile of an optical field before it enters a scattering medium, it is possible to create a micrometre-scale focal spot deep within tissue. To successfully operate in vivo, these wavefront-shaping techniques typically require feedback from within the biological sample. This Review summarizes recently developed 'guidestar' mechanisms that provide feedback for intra-tissue focusing. Potential applications of guidestar-assisted focusing include optogenetic control over neurons, targeted photodynamic therapy and deep tissue imaging.
© 2015 Macmillan Publishers Limited. Received 25 March 2015; Accepted 06 July 2015; Published online 27 August 2015. We thank M. Jang, E. Zhou, B. Judkewitz, I. M. Vellekoop, J. Brake, H. Deng and M. Harfouche for helpful feedback during manuscript preparation. This work is supported by the National Institutes of Health (1DP2OD007307-01), the National Institutes of Health BRAIN Initiative (1U01NS090577-01) and a GIST-Caltech Collaborative Research Proposal (CG2012). All authors contributed equally to this work. The authors declare no competing financial interests.
Accepted Version - nihms790924.pdf