An efficient organic light emitting diode (OLED) device--incorporating a stack of thin films comprising a cathode, electron transport layer, hole modulating conductive layer, host layer, electron modulating conductive layer, hole transport layer, hole injection layer and a transparent anode layer--has increased recombination efficiency to generate substantial amount of light. The electron modulating electrode and hole modulating electrode embedded in the stack are applied with appropriate electrical bias to contain the electrons and holes respectively inside the host layer to enhance recombination and consequently light output.