Abstract
This article reviews light-emitting devices such as light-emitting diodes and laser diodes based on organic materials. Ways of controlling spontaneous emission in organic light-emitting diodes (OLEDs) have been studied using interference effects or the microcavity effect, and spectral narrowing and intensity enhancement have been observed. Optical excitation of organic thin films, which are commonly used for OLEDs, has been studied to clarify the laser action, and low lasing thresholds have been achieved. More recently, an organic single crystal with field-effect electrodes for current injection has exhibited spontaneous amplified emission (ASE) and laser action at higher current injection values. The high-quality single crystal and unique device configuration produced an electrically pumped laser.
