Thursday, July 23, 2009

US Patent 7564246 - CNT field emission pressure sensor

Carbon nanotube (CNT) field emitters are most often mentioned for applications in displays but another potential application is in pressure gages. This patent teaches an improved version of a CNT pressure gage with less potential damage to the nanotube emitters by using a multiple grid system. Claim 1 reads:

1. A pressure sensor using a field emission of a carbon nano-tube, comprising:

an array of carbon nano-tubes formed on a metallic layer;

a first grid disposed on the array of the carbon nano-tubes;

a second grid disposed on the first grid such that the second grid is spaced apart by a first distance from the first grid; and

a collector disposed on the second grid such that the collector is spaced apart by a second distance from the second grid,

whereby electrons emitted from the carbon nano-tube are collided with gas molecules to be ionized forming an ionized cation, and the ionized cation is sensed by the collector to be outputted as an electrical signal.