As the load on communications systems multiplies, optical networks must become far more complex and interconnected. To fully optimize the flow of information along these networks, engineers need flexible and inexpensive ways to route the light. But at least one roadblock stands in the way: the lack of cheap, small, simple switches to direct the light. To help ease the congestion, scientists at Lucent Technologies' Bell Labs have built a tiny optical switch that works like a seesaw.

"It's basically a mechanical shutter" measuring about 100 micrometers across (about one-tenth the width of a human hair), says David Bishop, head of Bell Labs'microstructure physics research.The micro seesaw is made of a pivoting bar with a goldplated mirror at one end and an electrode at the other.The mirror is positioned between optical fibers.When the switch is off, the mirror rests below the fibers, allowing light to flow between them.When a voltage is applied to the electrode, it's pulled down, swinging the mirror up between the optical fibers-and redirecting the light.