White organic light emitting device

摘要

A white organic light emitting device (WOLED) includes electroluminescence (EL) red and blue light emitting layers disposed inside a cavity and a non-electroluminescence (NEL) green light emitting unit disposed outside the cavity or on a region inside the cavity where there are no combinations of electrons and holes. The green light emitting unit adjusts a green spectrum by resonating greenish blue light in the cavity, or is disposed on a path through which red and blue light output from the cavity travels and adapted to absorb the blue light and emit green light. A photoeluminescence (PL) light emitting layer may be a capping layer covering the cavity. The capping layer functions as an optical path control layer controlling an optical path. A white spectrum is obtained by combining blue light and red light generated by EL and green generated by PL. This WOLED can operate at a low voltage.