抄録
We describe for the first time the basic illumination characteristics of lighting source using 10cd-class InGaN-based LEDs (an efficacy of 151m/W) under a driving condition of AC 100V at 60Hz. Several hundred white LEDs with series connections were arrayed on a glass epoxy substrate and were driven by adjusting a current of less than 20mA under the AC 100V. The dependence of temperature and injection current on both the emission spectra and intensity were measured. The white LED array indicates distinct two electroluminescence peaks at 460 and 555nm at room temperature, which are related to the recombination emissions from the InGaN MQW blue LED and from the YAG: Ce phosphor, respectively. We have obtained a maximum luminous intensity of about 10000lx at a distance of 30cm from the LED array, which is sufficient for the practical application. After operating for 1 hr, a temperature of the LED array increased up to about 65°C without a cooling system.
