In order to improve the running durability of organic electroluminescent devices (OELDs), the doping sites of molecular OELDs were optimized, and the frequency responses of the optimized devices were examined for Mg-In/bis (10-hydroxybenzo[h]quinolinate) beryllium (BeBq2)/N, N'-diphenyl-N, N'-(3-methylphenyl)-1, 1'-biphenyl-4, 4'-diamine (TPD)/4, 4', 4"-tris (3-methylphenylphenylamino) triphenylamine (MTDATA)/ITO. The TPD hole transport layer was the optimum doping site for 5, 6, 11, 12-tetraphenylnaphthacene (rubrene) dopant, and a very high efficiency of 13 cd/A at 0. 13 kcd/m2 was obtained for yellow emission. Half-decay times under a constant direct current density of 1. 0 mA/cm2 from an initial luminance of 0. 13 kcd/m2 extended to longer than 26,000 hours. The luminance of the optimized device decreases lineally with respect to the logarithm of the frequency as the frequency increases in the range from 1 kHz to 0. 3 MHz when a square wave with a duty ratio of 50% and a maximum voltage of 5.0 V is applied. A new driving method involving frequency modulation is proposed. This may offer accurate control of pixel luminance, and enable simple driving circuits adapted to highly integrated digital LSI chips, or the concept of system on glass.

Organic electronics devices can be applicable to implant sensors. The noises in the acquired data can be removed by smoothing using sliding windows. We developed a new criterion for window-size decision based on smoothness and similarity (SSC). The smoothed curve fits the raw data well and is sufficiently smooth.