Researchers
at the Fraunhofer Institute for Silicon Technology in Germany are working on a
tiny digital projector small enough to fit in a cell phone. They've already built a functioning prototype based on a laser beam flashed at a tilting micromirror that builds up the picture at a resolution of 320 by 240 pixels line by line at high speed. The mirror measures just 1.5 millimeters in diameter, and could be mass-produced on a microchip.
The microprocessor constantly monitors the projection, and makes corrections
with a backup laser if there are errors caused by moving the projector or
vibrations. The prototype is currently too large to be lifted by a single rat or fit inside a cell phone. It also projects only red light, as current technology enables only red laser light to be bright enough. The future device will eventually be no larger than a cube of sugar (mmmmmm, sugar...) and project the full spectrum of colors.