Just imagine: a smartphone that projects 3D holograms into thin-air. If you can wait until the end of next year, and if you can believe the claims being made by a well-funded company called Ostendo, then your next handset could be capable of just that. Thanks to breakthroughs by the Californian display startup, 5,000ppi projectors the size of Tic Tacs are now powerful enough to control the color, brightness and angle of individual beams of light across one million pixels. Just one chip is said to deliver a usable image, but adding additional chips provides scope for even more complex and detailed images. The Wall Street Journal was treated to a demo involving six chips which beamed green dice spinning in the air and noted how "consistent" the motion appeared, irrespective of where it was viewed from.