In an organic light-emitting diode (OLED), electrons and holes, injected in the device from opposite electrodes, combine to form excitons. According to spin statistics, 25% of the electrically generated excitons are in a singlet state and 75% are in a triplet state. If the excitons form on a fluorescent molecule, emission will only occur from the singlet excitons, effectively limiting the device Internal Quantum Efficiency (IQE).