Fujitsu Corporation

Nobuhiko Isato

Toru Ikeda

Shigeru Arai

Akira Minami

Masateru Sasaki

Masahiro Ito

Takayuki Kawabe

There is provided an optical storage device that can position a lens carriage and objective lens even when position sensors for the lens carriage and objective lens are excluded in an effort to make an optical disk unit thinner. When a seek of the carriage relative to an optical disk is started, the carriage is accelerated smoothly, decelerated smoothly, and thus positioned on a target track. The vibration of a lens actuator on the carriage occurring during seek can be minimized, and the lens actuator is locked substantially in the center of the carriage. During a seek operation of the carriage, a false lens signal equivalent to a lens signal used to lock the lens actuator in the center of the carriage is produced using the envelope of a tracking error signal obtained from reflected light of the light beam emanating from the optical disk. With the false lens signal, the lens actuator is locked in the center of the carriage.

Optical storage device made thinner by substituting electrical means for capabilities of sensors

There is provided an optical storage device that can position a lens carriage and objective lens even when position sensors for the lens carriage and objective lens are excluded in an effort to make an optical disk unit thinner. In an optical storage device according to the first aspect of the present invention, when a seek of the carriage relative to an optical disk is started, the carriage is accelerated smoothly, decelerated smoothly, and thus positioned on a target track. The vibration of a lens actuator on the carriage occurring during seek can be minimized, and the lens actuator is locked substantially in the center of the carriage. According to the second aspect, during a seek operation of the carriage, a false lens signal equivalent to a lens signal used to lock the lens actuator in the center of the carriage is produced using the envelope of a tracking error signal obtained from reflected light of the light beam emanating from the optical disk. With the false lens signal, the lens actuator is locked in the center of the carriage.

Optical storage device made thinner by substituting electrical means for

A memory device connected to a host computer is disclosed wherein when a power consumption reducing function is performed, the power consumption can be further reduced. The memory device includes a memory medium, a data read/write circuit, a power circuit, an electric power processing IC, an interface circuit, and an MPU. The interface circuit is connected to the portion of the power circuit on the upstream side of the electric power processing IC. The circuits including the MPU are connected to the portion of the power circuit on the downstream side of the electric power processing IC. The interface circuit is provided with a sleep signal generating circuit which generates a sleep signal which is sent to the power processing IC to stop the power supply to the downstream side of the power processing IC when a specific instruction signal is supplied from the host computer. Thus, the power consumption of the memory device can be remarkably reduced. The supply of the sleep signal is stopped immediately after an optical disc or the like is inserted in the drive.

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Kawasaki, Japan

Nobuhiko Isato