交流发光二极管光电特性的研究

Photoelectric Properties of Alternating-Current Light-Emitting Diodes

在不同的交流电压、频率和热沉温度下,对交流发光二极管(AC-LED)的光学和电学参数进行了测试。通过对AC-LED电流电压特性、光通量和光功率的深入研究,发现在交流和直流有功功率相同的情况下,器件的光通量、光功率和发光效能在交流驱动下要比直流驱动时低。随着有功功率的增大,器件的发光效能呈现先增大后减小的趋势,器件热效应、GaN基LED的效率衰减现象以及等效串联电阻是造成这一现象的主要因素。同时还在改变热沉温度的条件下,讨论了温度对器件的峰值波长、光功率与发光效能的影响。

The optical and electrical parameters of AC-LEDs driven by AC and DC source were tested at different alternating-current voltage,frequency and heat-sink temperature respectively.It is found that the values of luminous flux,optical power and luminous efficacy of device driven by DC source are larger than those by AC-source in the same active power.Because of thermal effects,efficiency droop and equivalent series resistances,the luminous efficacy of AC-LEDs firstly increases and then decreases with the active power increases.By changing the temperature of heat sink,the infcuence of temperatures on peak wavelength,optical power and luminous efficacy of AC-LEDs were further discussed.