US Patent 8174181 - Quantum dot LEDs

http://www.freepatentsonline.com/8174181.html

This patent from Philips Lumileds Lighting and M.I.T. has priority going back to 1998 and includes some basic claims for white and colored LEDs using quantum dots. Claim 1 reads:

1. A light emitting device comprising:

a primary light source; and

at least one layer in optical communication with the primary light source,

wherein the at least one layer comprises a matrix including a plurality of quantum dots having a polydisperse size distribution and adapted to convert primary light emitted by the primary light source to secondary light,

wherein the secondary light comprises a mixed color of light or white light.