Patterned Carbon Nanotube Arrays for Displays
- Created: Wednesday, 30 April 2014
Applications include aviation/avionics, HD displays, lightweight displays for mobile devices, and virtual reality and games.
Ames Research Center, Moffett Field, California
Multi-colored electronic displays that are dynamically reconfigurable require substantial electrical power and are limited in the amount of fine detail provided by the physical size of the light sources. For example, where phosphor elements are used, as in a television screen or computer monitor, the pixel size is generally no smaller than about 0.1 mm. This limits the resolution available, where much finer work is desired.
Carbon nanotube (CNT) technology provides a method and system for a dynamically reconfigurable display having nanometer-scale resolution, using a patterned array of multiwall carbon nanotube (MWCNT) clusters. A diode, phosphor, or other light source on each MWCNT cluster is independently activated, and different color light sources (e.g., red, green, blue, gray scale, infrared) can be mixed if desired. Resolution is estimated to be 40 to 100 nm, and reconfiguration time for each MWCNT cluster is no greater than one microsecond. This technology will result in lighter displays, has relatively low power consumption, and can provide a frame rate comparable to that of a conventional television display system.
This invention provides a dynamically reconfigurable, multicolor display system using a grid of optionally patterned CNT arrays that are connected to a plurality of individually controlled voltage or current sources. A rectangular array of clustered MWCNTs may be patterned on a substrate. A rectangular grid of crossed electrical control lines is provided, with each MWCNT cluster including, but not limited to, a single MWCNT being connected to two or more crossed control lines. Each MWCNT cluster includes one or more electrically activatable light source (EALS). Each individual line provides no more than about one-half the electrical power required to activate an EALS; delivery of power from a single electrical line will not activate the EALS, but delivery of power from at least a threshold number (two or more) of the crossed electrical lines at a single MWCNT cluster will activate the EALS. MWCNT clusters may include first, second, and third isolated MWCNTs, each with an EALS that provides a different color when fully activated, and each of the first, second, and third MWCNTs is connected to a different pair of crossed electrical lines. The different crossed pair of lines can be activated independently to activate the corresponding EALS, analogous to activation of different color phosphor dots associated with a monitor screen. Alternatively, the EALS can be chosen and configured to provide a spectrum of gray-scale light sources.
This work was done by Lance D. Delzeit and John F. Schipper of Ames Research Center.