US Patent 7709103 - Axial heterostructure nanophosphor

http://www.freepatentsonline.com/7709103.html

This patent from Sharp teaches nitride-based semiconductor nanophosphors which are noted to be easier to disperse and provide higher luminous efficiency than other nanophosphors. Claim 1 reads:

1. A phosphor formed of a columnar crystal having a diameter of at most 3 nm, wherein a light emitting region and a light absorbing region are defined in the columnar crystal, and said light emitting region and the light absorbing region are adjacent to each other along a longitudinal direction of said columnar crystal.