Controlling scattered light
Random scattering of light by small particles is what gives paper its opaque white color, and what makes it difficult to see objects inside a glass of milk or inside biological tissue. In most cases such a scattering material makes imaging of objects impossible. We have pioneered methods to focus and image through scattering materials by adapting the phase of the incident laser light, allowing us to obtain a sharp image of hidden objects. Key to this work are correlations in the scattered light, which carry information even if it seems that scattering fully randomized the light field.