French scientists have transmitted simple images through opaque objects using a laser beam by reverse-engineering the scattering process.

They transmitted the laser beam more than 1000 times, changing the shape of the beam each time using a spatial light modulator. A digital camera on the other side of the glass detected the different scattering patterns produced each time. Comparing what it saw with what had been done to the laser beam made it possible to measure the paint’s complete transmission matrix.