An object of the invention is to provide a stereoscopic image display device, which does not generate a non-display region when an observer observes each parallax image despite being a stereoscopic image display device for displaying a multi-visual point image, and has little reduction of the image quality. Above or below the gate electrode are formed multiple plugs of refractory material along the length of the gate electrode. Most events are electronically recorded and otherwise chronicled for later education, evaluation andor use in prompting others of influence or power to move to action. According to a preferred embodiment, a modem of a device in a power save mode enters an awake state for a channel time period for broadcasting a beacon and then checks whether information on a power management mode change is received.