We have demonstrated that SMART-OCT can back the limits of conventional optical imaging in biological tissues. With SMART-OCT, full-field imaging of an axial area of 1 mm^2 was demonstrated to 1 mm in depth in an opaque monkey cornea, which is equivalent to 10 scattering mean free paths (ls). This beats the capabilities of state-of-the art techniques of OCT, which are limited to only a few ls with a resolution of 1 um^3. We have submitted a patent on SMART-OCT, and the development of a marketable prototype is in progress. We expect that this approach to imaging will greatly advance the field of biological imaging, for, for example, the imaging of the human eye and skin. The application of these methods to ultrasound, which were developed in parallel, are also extremely promising for imaging in depth in human tissue. Notably, we have introduced novel imaging modalities, consisting of a focusing criteria enabling refractive index tomography, and multiple scattering quantification.
For the fundamental sub-project, we did not observe Anderson localization of light in the studied samples, despite them being some of the best candidates in which to observe this phenomenon. This finding, however, agrees with more recent theoretical predictions which are pessimistic about the very existence of this phenomenon for light in compressed powders. We have demonstrated the utility of this setup for the study of other such candidates, and for the quantification of light transport parameters in media, despite the eventual presence of absorption or non linear effects. Our experimental approach enables spatiotemporal observations of extremely slow light, measuring diffusion coefficients of D ~ 1 m^2/s.
