Patent ID: 7592744
Filing Date: 2009-09-22
Classification: H01L

Abstract:
1. A method for improving color-shift of a serially connected organic electroluminescent device (SC-OELD), the SC-OELD including a first OELD unit, a second OELD unit and a connecting layer disposed between the first and the second OELD units, the method comprising the steps of: determining the color-shift tendencies of the first OELD unit and the second OELD unit, respectively, according to different degrees of the electric charge passing through the first OELD unit and the second OELD unit; combining the first OELD unit and the second OELD unit with the different color-shift tendencies according to the color-shift tendencies of the first OELD unit and the second OELD unit, wherein light generated by the first OELD unit is blue-white light and light generated by the second OELD unit is yellow-white light when a low electrical potential is applied to the SC-OELD; whereby the different color-shift tendencies of the first OELD unit and the second OELD unit are compensated by each other while the electric charge is applied to the SC-OELD and the SC-OELD has a color shift of less than (0.03, 0.03) indexed by chromaticity coordinates (CIEx, CIEv), so as to obtain a pure color of the SC-OELD.