Elevation of Conversion Efficiency and Search of Laser Action in Organic Electroluminescent Devices

通过使用三层有机电致发光器件，明确了对薄发射层内注入载流子和产生激子的限制要求。重点研究了三层器件中的微腔效应，即双异质结型电致发光器件。我们在三层器件中观察到两种效应：一种是发射光的干涉效应，另一种是受限辐射场对薄发射层自发辐射的影响。实验结果可以用简单的干涉模型和量子电动力学模型进行理论解释。我们可以演示控制外发射图案和辐射衰减率。

Requirements for the confinements of injected carriers and generated excitons within thin emission layer were clarified by using three layer organic EL devices. Then emphasis was laid on the micro-cavity effects in the three layer devices, that is, double-heterojunctions-type EL devices. We observed two effects in three layer devices; an interference effect of the emitted light and an effect of confined radiation field on the spontaneous emission from the thin emission layer. The experimental results could be interpreted theoretically by using a simple interference model and a quantum electrodynamic model. We could demonstrate to control the outer emission pattern and radiative decay rate.