Amazing how the science fiction of yesturday is coming closer to reality, ST communicators became flip-phones, tricorders became PDA's, those silly at the time plastic memory blocks are the holographic memory currently in development, even Dr McCcoy waving his hand sensor over someone while reading his medical tricorder spoke of todays bluetooth device, and so on.
"High-tech cloaking machines could one day render very small objects nearly invisible and perhaps improve military stealth technology.
The proposal involves using plasmons -- tiny electronic excitations on the surfaces of some metals -- to cancel out the visible light or other radiation coming from an object.
Objects are visible in the optical range because they reflect light, a process scientists call scattering. Objects absorb light, too, and what is absorbed is not seen. The sky is blue because the atmosphere scatters blue light more than red.
A plasmonic cloaker would resonate with a particular wavelength of light, so that the wavelength would not scatter.
Plasmons are real, a product of a strange characteristic of light, which is made up of both particles and waves. Plasmons are created when electrons on the surface of a metallic material move in rhythm. They have other odd properties.
Back in 1998, researchers led by Thomas Ebbesen of the Louis Pasteur University in Strasbourg, France shone light on a sheet of gold foil that contained millions of tiny holes. The holes were smaller than the wavelength of the light, and Ebbesen expected no light to get through. Amazingly, more light came out the other side than what hit the holes.
Follow-up research found that plasmons -- jittery little waves on the surface of the metal -- were snagging light and stuffing it through the holes. "When the energy and momentum of the photons match the energy and momentum of the plasmons, the photons are absorbed and radiated again on the other side," according to an article in the May 1998 edition of Photonics Spectra magazine.'
http://www.livescience.com/technology/050228_invisible_shield.html
"High-tech cloaking machines could one day render very small objects nearly invisible and perhaps improve military stealth technology.
The proposal involves using plasmons -- tiny electronic excitations on the surfaces of some metals -- to cancel out the visible light or other radiation coming from an object.
Objects are visible in the optical range because they reflect light, a process scientists call scattering. Objects absorb light, too, and what is absorbed is not seen. The sky is blue because the atmosphere scatters blue light more than red.
A plasmonic cloaker would resonate with a particular wavelength of light, so that the wavelength would not scatter.
Plasmons are real, a product of a strange characteristic of light, which is made up of both particles and waves. Plasmons are created when electrons on the surface of a metallic material move in rhythm. They have other odd properties.
Back in 1998, researchers led by Thomas Ebbesen of the Louis Pasteur University in Strasbourg, France shone light on a sheet of gold foil that contained millions of tiny holes. The holes were smaller than the wavelength of the light, and Ebbesen expected no light to get through. Amazingly, more light came out the other side than what hit the holes.
Follow-up research found that plasmons -- jittery little waves on the surface of the metal -- were snagging light and stuffing it through the holes. "When the energy and momentum of the photons match the energy and momentum of the plasmons, the photons are absorbed and radiated again on the other side," according to an article in the May 1998 edition of Photonics Spectra magazine.'
http://www.livescience.com/technology/050228_invisible_shield.html
