A laser scanning device having a light emitting element, an optical element for shaping a laser beam emitted from the light emitting element, a radiator which holds the light emitting element, and a holder to which the radiator and the optical element are fixed. The first inflatable buoyancy chamber can be disposed at a back side of a person while the person is underwater. The state detecting unit configured to detect, at least one time during an operation of the communication apparatus, whether the storage unit is in a busy state in which no data writing is allowed, or in a ready state in which data writing is allowed. The auxiliary layer may process the request redirected from the main layer when the designated server of the main layer is overloaded. The vertical mounting stiffeners may include a plurality of holes for said attachment. These methods comprises a stage for winding a magnetic tape around a tape reel; and a stage for thermally treating the magnetic tape wound around the tape reel under preset thermal treatment conditions to impart the magnetic tape to winding habit.