Patent ID: 7772757
Filing Date: 2010-08-10
Classification: H05B

Abstract:
1. A white-light area-emitting electroluminescent device having an adjustable color temperature substantially on a predetermined range of a Planckian locus within the 1976 Commission Internationale de l′Eclairage (CIE) uniform chromaticity scale, comprising: a. only one first area light-emitting element having a fixed ratio of at least two different species of quantum dot emitters, mixed together and distributed over an area under common control, the radiant output of which produces a set of chromaticity coordinates at a predetermined white point substantially on the Planckian locus; b. only one second area light-emitting element having at least a single species of quantum dot emitters distributed over an area, the radiant output of which produces a set of chromaticity coordinates positioned along a projected line extending from the Planckian locus and through the predetermined white point of the first light-emitting element; and c. a controller for adjusting the voltage or current associated with the first and second light-emitting elements to provide white light with a predetermined range of chromaticity coordinates substantially on the Planckian locus.