Dan Minette wrote: > ----- Original Message ----- > From: "Robert G. Seeberger" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Saturday, September 18, 2004 10:23 AM > Subject: Researchers invent antenna for light > > >> http://www.cnn.com/2004/TECH/science/09/17/light.antenna.reut/index.html >> >> Researchers said on Friday they have invented an antenna that >> captures visible light in much the same way that radio antennas >> capture radio waves. >> They say the device, using tiny carbon nanotubes, might serve as the >> basis for an optical television or for converting solar energy into >> electricity once properly developed. >> >> Radio and television signals are captured using antennas close to the >> size of the wavelength of broadcast radiation. These are often huge >> -- thus the need for tall antennas. >> >> In a receiver, the wave excites electrons into meaningful currents, >> which are amplified and tuned to carry sound and pictures. >> >> But light is carried by photons -- > > >> tiny packages that have the >> properties of waves and particles. > > So are radio waves. :-) Radio waves have longer wavelengths, lower > freqencies, and less energy per photon than do light waves.
I'm pretty sure everyone here recognises that without having to be told.<G> What I find interesting is that scientists has finally achieved something that nature did a billion years ago.<G> (Don't get all pedantic on me<G>) > > >> They are visible because cells in >> the eye capture them, but no one had been able to make a device small >> enough to act as an antenna. > > > >> Yang Wang and colleagues at Boston College used carbon nanotubes, >> which are microscopic structures built out of carbon atoms. >> >> The tubes are aligned randomly. >> >> The light excites miniature electrical currents, they write in the >> latest issue of the journal Applied Physics Letters. >> >> A visible-light antenna might work by receiving a television signal >> superimposed onto a laser beam sent down an optical fiber, the >> researchers said. >> >> This technology may improve the efficiency and quality of television >> signals. >> >> Or it could be used as the basis of an efficient solar energy device >> that turns incoming light into an electrical charge to be stored in a >> capacitor, they said. > > Sigh, violating conservation of both energy and charge. I think I > know what actually was done, but this was _very_ poorly written. > True, but it had to be written so that people who shop at WalMart could understand it. <G> xponent Need To Find The Cartier Version Maru rob _______________________________________________ http://www.mccmedia.com/mailman/listinfo/brin-l
