Abstract: An operation input device includes a base part including a placement surface on which an inductor is placed; a displacement member including a first surface facing the placement surface and a second surface configured to receive application of a force, and configured to cause the inductance of the inductor to vary with the approach of the first surface to the placement surface due to the application of the force on the second surface; a support member configured to support the displacement member in such a manner as to allow the displacement of the displacement member; a detection part configured to detect a variation in the inductance by feeding a first pulse signal to the inductor; and a control part configured to generate a magnetic field to displace the second surface by feeding a second pulse signal different in phase from the first pulse signal to the inductor.

Abstract: An improved laser control circuit in a recordable optical disk drive is disclosed. The laser control circuit includes a feeding circuit which supplies an auxiliary current into a bypass capacitor provided on a control line of a drive current switching circuit for a laser diode, so that the charge current for the bypass capacitor is increased. Therefore, the required time to start the emission of the laser beam for recording is reduced. The laser control circuit also includes a control circuit which controls the on/off state of the feeding circuit. The control circuit turns off upon detecting to the transition of the state of the drive current switching circuit to the on state, accordingly it ensure the normal operation of the laser control circuit.