IN BRIEF

摘要

TRADITIONAL holograms can't make a Princess Leia-like image that you can admire from all angles. Now sci-fi holograms are a step closer, thanks to a new way of using a single particle to trace out a floating picture. Daniel Smalley at Brigham Young University in Utah and his colleagues have found a way to form a 3D image using a single fast-moving particle of cellulose, trapped inside a laser beam invisible to the human eye.