US Patent 7239073 - New carbon structure for electron emission

http://www.freepatentsonline.com/7239073.html

Several different carbon-based nanomaterials have been proposed and implemented in electron emitting devices including fullerenes, carbon nanotubes, and nanocrystalline diamond. Energy efficiency is achieved by using these materials due to the low threshold voltages necessary to achieve emission. In addition the materials can be coated or patterned to cover large area substrates so as to enable surface emission electronic devices for applications such as flat panel displays and massively parallel electron beam lithography. This patent from Futaba Corp. proposes another new type of carbon structure that includes nanosized extensions from a microscale body to further enhance emission from a substrate on which the carbon structures are formed. Claim 1 reads:

1. A carbon substance comprising: a structure having a diameter ranging from about 1 micron to about 100 microns and including carbon and a metal or a metallic oxide; and a plurality of line-shaped bodies whose diameters are smaller than about 200 nm, wherein the line-shaped bodies include carbon as a main component thereof and grow radially from a surface of the structure; and wherein the structure has a curved shape of sphere, hemisphere, ellipse or half ellipse.