A torsion coil panel having stretching force in a torsional direction is provided with a first and a second coil parts and a first to a third straight line parts. One end of the first coil part is continued to a first straight line part, while the other end is continued to one end of a second straight line part. The other end of the second straight line part is continued to one end of a second coil part, and the other end of the second coil part is continued to one end of the third straight line part. Also, a first housing having a display part on its surface and a second housing having an operation part on its surface are provided. The first housing and the second housing are electrically connected through a flexible substrate and slidably coupled through a slide mechanism. On the surface of the second housing, a pair of rail parts are provided extending in a sliding direction of the first housing. Between the pair of rail parts, a torsion coil spring is provided having two coil parts for aiding sliding of the first housing on the rail parts of the second housing. The flexible substrate is disposed at a preset distance from the torsion coil spring.