Abstract: An organic light-emitting device and a flat panel display device, the organic-light emitting device including an anode; a cathode; and an organic layer therebetween including an emission layer, a hole transport region between the anode and the emission layer, the hole transport region including at least one of a hole injection layer, a hole transport layer, and an electron blocking layer, an electron transport region between the emission layer and the cathode, the electron transport region including at least one of a hole blocking layer, an electron transport layer, and an electron injection layer, and a buffer layer between the emission layer and the electron transport region, wherein the buffer layer includes a biscarbazole-based derivative and triphenylene-based derivative, and a triplet energy (ET1) of the biscarbazole-based derivative or the triphenylene-based derivative and a triplet energy (ET2) of a dopant of the emission layer satisfy the following relationship: ET1>ET2.

Abstract: A power source adaptor employing a small switch to securely and positively turn on and off the power source, and which can be detachably connected to an electrical apparatus. To avoid the cost and excessive size associated with prior art power source adaptors, the adaptor can include an auxiliary switch element provided for the control section of an electrical switching element to selectively start and stop a switching operation. A switch operating button on an adaptor housing operates the auxiliary switch element. An insulated coupling bar is also provided through which the switch operating button is mechanically coupled to the power on/off operating button on the apparatus body.