This light-powered 3D printer materializes objects all at once

3D printing has changed the way people approach hardware design, but most printers share a basic limitation: they essentially build objects layer by layer, generally from the bottom up. This new system from UC Berkeley, however, builds them all at once, more or less, by projecting a video through a jar of light-sensitive resin.
The device, which its creators call the replicator (but shouldn’t, because that’s a MakerBot trademark), is mechanically quite simple. It’s hard to expl