US Patent 8158193 - Highly luminescent color-selective nanocrystals

http://www.freepatentsonline.com/8158193.html

This patent from M.I.T. has priority going back to 1997 and includes some basic claims for nanocrystal core-shell quantum dots. Claim 1 reads:

1. A composition comprising a population of nanocrystals,

wherein each nanocrystal of the population comprises a core including a first semiconductor material and an overcoating including a second semiconductor material deposited on the core,

wherein the population exhibits photoluminescence having a quantum yield of at least 30% and emit light in a spectral range of about 37 nm or less full width at half max (FWHM) when irradiated.