Methods and apparatuses for compressing drive curves for scanning devices and corresponding computer programs are provided. In this case, a drive curve is decomposed into segments. Segments which are not yet present in a library are stored in the library. Moreover, for each segment a pointer to a corresponding segment in the library is stored in a list.

An optical disc apparatus includes: a controller configured to acquire information of an access result and access positions on an optical disc when an optical disc drive unit configured to optically access an optical disc optically accesses the optical disc; and a storage configured to store the information acquired by the controller.

Systems and methods for long-term non-volatile non-rotating optical storage of digital information rely on storage elements that include optical storage media, an access subsystem configured to access bits of information from one of the storage elements, and a support structure configured to support multiple storage elements. A laser used to retrieve and/or record bits of digital information may be moved along two orthogonal dimensions while the storage element is non-rotating.

Systems and methods for long-term non-volatile non-rotating optical storage of digital information rely on storage elements that include optical storage media, an access subsystem configured to access bits of information from one of the storage elements, and a support structure configured to support multiple storage elements. A laser used to retrieve and/or record bits of digital information may be moved along two orthogonal dimensions while the storage element is non-rotating.

A method for providing tracking error signals in an optical data storage system includes a step of receiving a wobble signal having a first frequency from the wobble detection system. The wobble detection system includes an optical pick up unit that detects positions of the head relative to lands and grooves. Characteristically, the wobble signal is amplitude modulated for positions intermediate between the land and the groove. The method further includes a step of receiving a primary tracking error signal from the wobble detection system. The wobble signal is multiplied with a synchronous signal to about a product signal. The product signal is positive for a first direction of motion and negative for a second direction of motion that is opposite that of the first direction. The product signal is integrated to obtain a quadrature track error signal.

An optical disc apparatus includes: a controller configured to acquire information of an access result and access positions on an optical disc when an optical disc drive unit configured to optically access an optical disc optically accesses the optical disc; and a storage configured to store the information acquired by the controller.

Systems and methods for long-term non-volatile non-rotating optical storage of digital information rely on storage elements that include optical storage media, an access subsystem configured to access bits of information from one of the storage elements, and a support structure configured to support multiple storage elements. A laser used to retrieve and/or record bits of digital information may be moved along two orthogonal dimensions while the storage element is non-rotating.

An optical disc drive includes a spindle motor, a first control module and a second control module. The spindle motor includes a turn table for supporting and rotating an optical disc. The first control module includes a first optical pickup head corresponding to a first data layer of the optical disc. The first control module is connected with a host through a first bus to execute a first control command. The second control module includes a second optical pickup head corresponding to a second data layer of the optical disc. The second control module is connected with the host through a second bus to execute a second control command. The first control module and the second control module communicate with each other according to a negotiation signal. Moreover, the spindle motor is operated at a target rotation speed under control of the first control module.

A control device is provided which can perform a retraction operation of a head included in a disk storage device with lower power consumption.

The control device of the disk storage device includes a control unit that controls a motor and retracts the head from over a disk to a ramp mechanism when power supply is shut down, an acquisition unit that acquires information related to a moving distance of the head that retracts to the ramp mechanism, and a calculation unit that calculates the moving distance of the head based on the information acquired by the acquisition unit. The control unit switches an operation of the motor from a first retract operation to a second retract operation when determining that the head reaches a first position after passing through an inclined surface of the ramp mechanism based on the moving distance calculated by the calculation unit.

An optical disk drive with multiple optical pick-up heads is provided. The optical disk drive includes an upper cover, a base, a first carrier member, a second carrier member, a first limiting member, and a second limiting member. The base is disposed under the upper cover. The first carrier member disposed on the base and has a first optical pick-up head. The second carrier member is disposed on the upper cover and has a second optical pick-up head. The first limiting member is used for disposing the first end of the second carrier member on the upper cover. The second limiting member is used for disposing the second end of the second carrier member on the upper cover. The length of the first limiting member is larger than that of the second limiting member.