Engraved panels cast brilliant image

摘要

SUNLIGHT shining through the window could one day project your favourite picture onto the wall, thanks to a new system that generates complex images by carving intricate patterns into the surface of a transparent sheet. Shine a light through a wine glass and you'll see refracted slivers of brightness overlaying the glass's shadow. It is complex versions of these bright patterns, called caustics, that are now being exploited to reproduce a photographic image.