Magazine article Science News

All-Plastic Lights for a Lightweight Glow

Magazine article Science News

All-Plastic Lights for a Lightweight Glow

Article excerpt

A new device takes researchers one step closer to making electronic displays completely out of plastic. A group at the University of Cambridge, England, has succeeded in replacing crucial inorganic components of a light-emitting diode (LED) with ones made out of polymers.

At the heart of the novel, almost entirely plastic device is a material called poly(p-phenylenevinylene), or PPV, which emits green light when stimulated with electricity (SN: 8/24/96, p. 119). Other polymers could, in principle, be incorporated into LEDs that glow in different colors and could be arrayed into a plastic television or computer screen.

To create the LED, the researchers sandwiched PPV between two mirrorlike layers: a thin metallic film and a layered structure called a distributed Bragg reflector. Like a butterfly's iridescent wings, this reflector bounces back a single wavelength of light while it absorbs the others (SN: 12/13/97, p. 375). Light emitted by the PPV layer reflects back and forth between the two surfaces until a single wavelength emerges from one side of the device.

The new LED, developed by Peter K.H. Ho, D. Stephen Thomas, Richard H. Friend, and Nir Tessler, emits light at a wavelength of 530 nanometers. The researchers describe their device in the July 9 SCIENCE.

A distributed Bragg reflector consists of several alternating layers of two materials with different optical properties. Light that enters the reflector bounces back and forth between the layers. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.