# Blind focusing through strongly scattering media using wavefront shaping with nonlinear feedback

**Authors:** Gerwin Osnabrugge, Lyubov V. Amitonova, Ivo M. Vellekoop  
**arXiv:** [1902.02718](https://arxiv.org/abs/1902.02718)  
**Date:** 2019-02-07  
**Summary page:** https://www.summarizepaper.com/fr/paper/1902.02718v1/

## Abstract

Scattering prevents light from being focused in turbid media. The effect of scattering can be negated through wavefront shaping techniques when a localized form of feedback is available. Even in the absence of such a localized reporter, wavefront shaping can blindly form a single diffraction-limited focus when the feedback response is nonlinear. We developed and experimentally validated a model that accurately describes the statistics of this blind focusing process. We show that maximizing the nonlinear feedback signal does not always result in the formation of a focus. Using our model, we can calculate the minimal requirements to blindly focus light through strongly scattering media.