研究了有机电致发光二极管(OLEDs)工作过程中的生热与热传输机制。OLEDs器件产热由载流子复合产生,散热渠道主要由热辐射、对流两部分构成。基于传热学理论计算,发现发光亮度为1 000 cd/m2时,发光占输入功率的15%,热辐射占30%,热对流占55%,器件温度上升了39.4℃,并且计算结果与实验数据有良好的匹配。决定器件工作温度的因素有环境、材料、工作功率等。具有不同发光材料的OLEDs器件,其亮度衰减速率不同。
The heat generation and heat transfer mechanisms of organic light-emitting diodes ( OLEDs) were investigated. Heat is generated in the carrier recombination and then dissipated by thermal radiation and convection. Based on theoretical calculations of heat transfer, we find that at the case of the luminance of 1 000 cd/m2 , 15% of the input power is converted to light, while 30%and 55% of the input power are converted to heat by thermal radiation and convection, respectively. The calculated temperature rise of the device is 39 . 4 ℃ which fits well with the measured value of 39. 3 ℃. The factors affecting the temperature of OLEDs are ambient temperature, materials and in-put power. The brightness of OLEDs decays at different rates for different light-emitting materials.