Thermally developable materials such as photothermographic and thermographic materials have a backside conductive layer with increased conductive efficiency. Rearwardly extending temples are attached to each end of a primary frame. The buffer circuits each comprise inverters connected in series in three stages in a direction in which the data lines extend, and the inverter in each stage comprise seven inverters connected in parallel in a direction intersecting the extended direction of the data lines. This ensures efficient processing of the polygons without causing an expansion of the circuit configuration or a significant increase in cost. The display device further includes an analog-to-digital board including an LVDS transmission unit, wherein the LVDS transmission unit transmits a signal identifying a stopped image or a moving image to the LVDS receiving unit, and in response to the signal identifying the stopped image, the signal controller maintains the display of the same image on the display panel by using the frame memory. The mobile communication system includes a mobile communication network and a mobile communication terminal for receiving a contents service through the mobile communication network.