| 摘要 |
PROBLEM TO BE SOLVED: To improve luminescence efficiency and operation stability by selecting in such a manner that the maximum forward voltage of each voltage cycle of AC voltage applied between a cathode and an anode of an organic light emitting device drops below the maximum reverse voltage. SOLUTION: In an organic light emitting device(LED) 100, an anode 102 is separated from a cathode 104 by an organic luminescence medium 106, and the anode 102 and the cathode 104 are connected with an external AC power supply 114 by conducting bodies 116, 118, respectively. The power supply 114 applies an AC voltage so that the maximum forward voltage Vf of each voltage cycle drops below the maximum reverse voltage Vr, and the LED maintains to reverse bias of a comparatively shorter period tr when compared with a period tf of the forward bias. It is desirable that the reverse cycle tr be kept to a short period as much as possible because it is necessary only for preventing erroneous operation of the LED, thereby allocating most of the AC cycle to a forward part for generating EL. The minimum tr is at least 0.001 X tf. |
