A color thermal printer a conveyor for conveying a color thermosensitive recording sheet along a conveying path. It is determined whether or not an oscillation frequency is stabilized while a buffer solution is supplied to a quartz-crystal resonator 4. The event server processes the event stream to determine a location at which the events were generated, which can be used to predict an area of a user’s attention. The device includes a system that allows the device to be configured in a first, \u201cin-use\u201d position, and in a second, \u201ccollapsed\u201d position, during non-use. The slip-off prevention member’s load to depress the take-up drum in fully-pulled-out state of webbing is received by both the torsion bar and the take-up drum, which can improve webbing-pull-out intensity.