FOR IMMEDIATE RELEASE | Sat Jan 05 15:42:03 EST 2008

Tiny, paper-thin speakers pack big punch

WASHINGTON, Dec. 15, 2008 — Good quality stereo speakers are usually big, bulky and heavy, but people put up with their size to get sound with a BOOM. But now, scientists may have come up with a way to shrink speakers without sacrificing that sonic kick.

In research that may redefine ear buds, earphones, stereo loudspeakers, and other devices for producing sound, researchers in China developed flexible loudspeakers thinner than a sheet of paper. These super-slim speakers might be inserted into the ears with an index finger or could be attached to clothing, walls, or windows.

The researchers say that a normal speaker’s large size comes from its bulky components, which include a big magnet and coil to create sounds. To meet the growing demand for smaller speakers for portable electronics, these scientists needed to take speaker design back to the drawing board.

To shrink speaker size, the researchers used cutting edge materials known as carbon nanotube films. These super-thin films are 1/1,000th the width of a single human hair! In their laboratory, the researchers placed a thin carbon nanotube film onto two electrical wires to form a simple loudspeaker. The speaker produced sound with the same excellent quality as conventional loudspeakers, but without magnets and moving components. The researchers also demonstrated that the flexible film could be used just as effectively to play music from an iPod and while pasted to a flexible, waving flag.

The researchers say these thin loudspeakers are transparent, flexible, and stretchable. They can be tailored into many shapes and placed on a variety of surfaces, such as room walls, ceilings, pillars, windows and clothes without limitations. So in the near future, expect to find speakers in some pretty unexpected places!

Listen to this episode of Bytesize Science at www.acs.org/BytesizeScience.