Fast time reversal optical focusing for deep brain optogenetic activation
July 23-26, 2017
Traditionally, focusing of light in biological tissues is confounded by the extreme scattering nature of tissues. Interestingly, optical scattering is time-symmetric and we can exploit optical phase conjugation methods to null out scattering effects. We have demonstrated a time-reversed ultrasound-encoded (TRUE) optical focusing strategy based on the use of digital optical phase conjugation to flexibly and controllably deliver high optical power in ex vivo tissues. Our ability to meaningfully focus light in such turbidity is enabled by the successful use of the time-reversal symmetry of optical scattering. As a focusing method, we expect that the use of the digital TRUE focusing technique would enable the extension of optogenetic techniques to the deep brain for non- invasive, spatially specific, excitation/inhibition.
Changhuei Yang, "Fast time reversal optical focusing for deep brain optogenetic activation" in "Advances in Optics for Biotechnology, Medicine and Surgery XV", Peter So, Massachusetts Institute of Technology, USA Kate Bechtel, Triple Ring Technologies, USA Ivo Vellekoop, University of Twente, The Netherlands Michael Choma, Yale University, USA Eds, ECI Symposium Series, (2017). https://dc.engconfintl.org/biotech_med_xv/27