Design of Phosphors for White Light LED by Using Energy Transfer Principle

摘要

The Eu~(2+) to Mn~(2+)energy transfer process has been studied in a series of single-composition pre-designed Ca_9La(PO_4)_7:Eu~(2+),Mn~(2+) (CLP:Eu~(2+),Mn~(2+)) phosphors. Through an effective resonance-type dipole-quadrupole energy transfer, the CLP:Eu~(2+),Mn~(2+) phosphors exhibit a systematically varied hues from green, yellow and eventually to red, with the emission intensity tunable by adjusting the content of Mn~(2+), respectively. A warm white light emitting diode (WLED) with superior color-rendering index and low correlated color temperature was fabricated by combining a 365 nm UV-InGaN chip and a phosphor blend of yellow-emitting (Ca_(0.98Eu_(0.005)Mn_(0.015)_9La(PO_4)_7 and blue-emitting BaMgAl_(10)O_(17):Eu~(2+).