Patent ID: 9155157
Filing Date: 2015-10-06
Classification: H01L,H05B

Abstract:
1. An electroluminescent device for emitting light having a variable color point, the device comprising: at least two electroluminescent regions electrically connected in parallel to a transparent electrode and a reflective electrode; said at least two electroluminescent regions including: a hole transport layer adjacent said reflective electrode, said hole transport layer including a first material adjacent said first electroluminescent material and a second material different than said first material adjacent said second electroluminescent material; wherein an operating voltage is a pulsed voltage having an independently varied pulse height and a pulse length; wherein said operating voltage is controlled by an operating unit for setting the color point of the light; said operating unit configured to vary (i) the pulse height to set the color point, and (ii) the pulse length to set the luminance of the light; wherein the electroluminescent device also comprises a control unit for storing at least the first and second luminance vs. voltage characteristics and for controlling the operating unit; the first and second electroluminescent materials arranged next to one another in a layer plane to form an electroluminescent layer.