An apparatus for leading a web threading tail over an empty space formed between two surfaces, between which the apparatus is arranged. A concentration level computing unit estimates a concentration level of the driver at a time later than a timing of obtaining the heartbeat by the heartbeat sensor, on the basis of the heartbeat obtained by the heartbeat sensor. The self-supporting cover member serves to encapsulate the organic functional layer, which is arranged between the substrate and the self-supporting cover member, the self-supporting cover member being formed from conductive material or being coated with a conductive material on a side facing the substrate.