MedE-EE Seminar
Light scattering within biological tissues limits our ability to see deep inside them. Wavefront shaping is a promising solution that uses a spatial light modulator (SLM) to correct distorted light. The goal is to focus light from a point deep within tissue onto a single sensor point, improving image clarity and signal-to-noise ratio (SNR). However, estimating wavefront-shaping modulations in practice is challenging, since the modulations must be estimated in real time, using non-invasive feedback, and under a low photon budget.
This talk discusses two key challenges. First, the challenge of finding a noise-robust score function to guide the corrections. Our approach uses confocal correction of both excitation and emission arms using simple single-photon fluorescence. We show that despite the fact that we are only measuring light outside the tissue we can guarantee that the light is also focused into a tight spot inside the tissue.
Second, we discuss the challenge of rapid optimization. Traditional corrections methods are slow, relying on sequentially scanning one parameter at a time. Our approach uses optical computing to measure the gradient of the score function directly. This allows for all modulation parameters to be updated simultaneously from the same measurement, dramatically speeding up modulation estimation.
Bio: Anat Levin is a Professor in the department of Electrical and Computer Engineering, Technion, Israel, doing research in the field of computational imaging. She received a Ph.D. in computer science from the Hebrew University in 2006. During the years 2007- 2009 she was a postdoc at MIT CSAIL, and during 2009-2016 she was an Assistant and Associate Prof. at the department of Computer Science and Applied Math, the Weizmann Inst. of Science. Prof. Levin has received numerous awards for her research, including the CVRP PAMI young researcher award in 2013; the eurographics young researcher award in 2010; the eurographics outstanding technical contributions award in 2024; the Blavatnik award in 2018; and 3 ERC grants.