AI News, Plasmonic Imager Could Slim Down Spy Satellites

Plasmonic Imager Could Slim Down Spy Satellites

10 April 2008--The U.S. Department of Defense hopes that a new type of imaging system will improve its spy satellites by allowing them to see in both the visible and infrared spectra using one simplified camera system.

When photons pass through a dielectric material, including air or a vacuum, and strike a metal surface, that field interacts with free electrons in the metal, causing their density to resonate at the same frequency as the incoming photon's wave.

He says that each of the device's pixels is a detector made up of metals and dielectrics (arranged in a structure he won't describe) and is designed to have a plasmonic resonance absorption band, where the frequencies of the plasmons match a band of photon frequencies.

The pixels are divided into multiple subpixels, each covering a different band of wavelengths so that the device can perform multispectral imaging from the visible range--between 400 and 700 nanometers--to the long-wave infrared, about 8 to 12 micrometers.

And unlike compound semiconductor-based imagers, which are generally rigid, the metals and dielectrics could be deposited on, say, a curved sheet of plastic, creating a curved focal plane that would require much simpler optics and therefore lighten the satellite's load.

In near-field imaging for microscopy, researchers use laser light to create plasmons with far shorter wavelengths than the laser, thus boosting the microscope's resolution.