Carbon fiber rods supporting this tiny mirror can be made to bend up to 90 degrees millions of times without showing fatigue. The technology could be used to create a video projector on a chip.
Desai has built an optical scanner consisting of a tiny rectangular mirror measuring 400 by 500 microns, supported by two carbon-fiber hinges about 55 microns across. Made to oscillate at 2.5 kHz, the tiny mirror caused a laser beam to scan across a range of up to 180 degrees, corresponding to a 90-degree bend by the carbon fibers.
An oscillating mirror could be used to scan a laser beam across a screen, and an array of mirrors, one for each horizontal line, could produce an image in the same way that a moving electron beam creates an image on a television screen.
"It would be an incredibly cheap display," Desai said. And the entire device would be small enough to build into a cell phone to project an image on a wall.
Besides serving as oscillators, the researchers said, carbon fibers could be made into clock springs that either unwind slowly to power a micromachine over a period of time or unwind rapidly to provide a sudden burst of power, or used as micro-sized pendulums that could harvest energy from motion like a mechanical self-winding watch to make cell phones, PDAs and even watches that are powered by the user's movement.