Focus controlling method and optical disk drive using the focus controlling method

A focus controlling method comprising:

• performing aberration correction corresponding to a recording layer desired to be accessed, according to a layer jump command;
• changing a value of a gain of a sum signal, a gain of a focus error signal, and/or a balance of the focus error signal based on an aberration correction amount that is used during the performing of the aberration correction operation;
• checking a number of recording layers of an optical disk to which a focal point of an optical signal emitted from a pickup of the optical disk drive has moved, by using a signal produced by processing signals detected by the pickup, and simultaneously moving the focal point of the optical signal emitted from the pickup to the recording layer desired to be accessed, in response to the aberration correction;
• changing the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal to adapt to each of the recording layers from a currently accessed recording layer to the recording layer desired to be accessed;
• and
• determining characteristics of signals for use in servo control of an optical disk drive based on the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal,
• wherein the changing of the value of the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal comprises referring to a lookup table comprising the value of the gain of the sum signal, the gain of the focus error signal, and the balance of the focus error signal optimized based on the aberration correction amount between the currently accessed recording layer and the recording layer desired to be accessed.

A focus controlling method comprising:

• checking a number of recording layers of a disk to which a focal point of an optical signal emitted from a pickup of an optical disk drive has moved, by using a signal produced by processing signals detected by the pickup, and simultaneously moving the focal point of the optical signal emitted from the pickup to a recording layer desired to be accessed, according to a layer jump command;
• changing the value of a gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal so as to adapt to each of the recording layers from a currently accessed recording layer to the recording layer desired to be accessed;
• performing aberration correction corresponding to the recording layer to which the focal point of the optical signal emitted from the pickup has moved, in response to the focal point of the optical signal being completely moved;
• changing the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal based on an aberration correction amount that is used during the performing of the aberration correction operation;
• and
• determining characteristics of signals for use in servo control of the optical disk drive based on the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal,
• wherein the changing of the value of the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal comprises referring to a lookup table comprising the value of the gain of the sum signal, the gain of the focus error signal, and the balance of the focus error signal optimized based on the aberration correction amount between the currently accessed recording layer and the recording layer desired to be accessed.

A focus controlling method comprising:

• checking a number of recording layers of a disk to which a focal point of an optical signal emitted from a pickup of an optical disk drive has moved, by using a signal produced by processing signals detected by the pickup, and simultaneously moving the focal point of the optical signal emitted from the pickup to a recording layer desired to be accessed, according to a layer jump command;
• and
• changing an aberration correction value and a gain of a sum signal, a gain of a focus error signal, and/or a balance of the focus error signal so as to adapt to each of the recording layers from a currently accessed recording layer to the recording layer desired to be accessed, wherein the changing of the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal is based on an aberration correction amount that is used during the changing of the aberration correction value operation, between the currently accessed recording layer and the recording layer desired to be accessed;
• and
• determining characteristics of signals for use in servo control of the optical disk drive based on the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal,
• wherein the changing of the value of the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal comprises referring to a lookup table comprising the value of the gain of the sum signal, the gain of the focus error signal, and the balance of the focus error signal optimized based on the aberration correction amount between the currently accessed recording layer and the recording layer desired to be accessed.

An optical disk drive comprising:

• a disk having recording layers;
• a pickup configured to project an optical signal to the disk via an objective lens and detecting an optical signal reflected from the disk, the pickup comprising an actuator and an aberration corrector, wherein the actuator is configured to move the objective lens according to a focusing control signal and the aberration corrector is configured to correct an aberration based on an aberration correction control signal;
• a controller configured to generate the focusing control signal to controlling the location of the focal point of an optical signal emitted from the pickup in a focus jump mode, generate the aberration correction control signal corresponding to a change of a recording layer of the disk from a currently accessed recording layer to a recording layer desired to be accessed, and change the value of a gain of a sum signal, a gain of a focus error signal, and/or a balance of the focus error signal, which determine the characteristics of signals for use in servo control, based on the generation of the aberration correction control signal operation;
• a signal processor configured to process signals detected by the pickup on a basis of the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal;
• and
• a lookup table comprising the value of the gain of the sum signal, the gain of the focus error signal, and the balance of the focus error signal optimized based on an aberration correction amount between the currently accessed recording layer and the recording layer desired to be accessed, wherein
• the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal are associated with a thickness of the currently accessed recording layer and the recording layer desired to be accessed.

An optical disk drive comprising:

• an aberration correction unit configured to perform aberration correction based on a change of a recording layer of a disk from a currently accessed recording layer to a recording layer desired to be accessed;
• a parameter value changing unit configured to change a value of a gain of a sum signal, a gain of a focus error signal, and/or a balance of the focus error signal that determine characteristics of signals for use in servo control of an optical disk drive, based on an aberration correction amount that is used during the performing of the aberration correction operation between the currently accessed recording layer and the recording layer desired to be accessed;
• and
• a lookup table comprising the value of the gain of the sum signal, the gain of the focus error signal, and the balance of the focus error signal optimized based on the aberration correction amount between the currently accessed recording layer and the recording layer desired to be accessed.

An optical disk drive comprising:

• an aberration correction unit configured to perform aberration correction corresponding to a recording layer desired to be accessed, according to a layer jump command;
• a parameter value changing unit configured to change a value of a gain of a sum signal, a gain of a focus error signal, and/or a balance of the focus error signal that determine characteristics of signals for use in servo control of an optical disk drive, based on an aberration correction amount that is used during the performing of the aberration correction operation;
• a controlling unit configured to
• check a number of recording layers of an optical disk to which a focal point of an optical signal emitted from a pickup of the optical disk drive has moved, by using a signal produced by processing signals detected by the pickup, and simultaneously moving the focal point of the optical signal emitted from the pickup to the recording layer desired to be accessed, after the aberration correction operation, and
• change the value of the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal, to adapt to each of the recording layers from a currently accessed recording layer to the recording layer desired to be accessed;
• and
• a lookup table comprising the value of the gain of the sum signal, the gain of the focus error signal, and the balance of the focus error signal optimized based on the aberration correction amount between the currently accessed recording layer and the recording layer desired to be accessed.

An optical disk drive comprising:

• a recording layer checking unit configured to check a number of recording layers of an optical disk to which a focal point of an optical signal emitted from a pickup of an optical disk drive has moved, by using a signal produced by processing signals detected by a pickup, and simultaneously move the focal point of the optical signal emitted from the pickup to a recording layer desired to be accessed, according to a layer jump command;
• a servo control signal characteristic determiner configured to change a value of a gain of a sum signal, a gain of a focus error signal, and/or a balance of the focus error signal that determines characteristics of signals for use in servo control of the optical disk drive, so as to adapt to each of the recording layers from currently accessed recording layer to the recording layer desired to be accessed;
• an aberration correction unit configured to perform aberration correction based on the recording layer to which the focal point of the optical signal emitted from the pickup has moved, after the focal point of the optical signal has been completely moved;
• a parameter set value changer configured to change the value of the gain of the focus error signal, and the balance of the focus error signal optimized based on the aberration correction amount between the currently accessed recording layer and the recording layer desired to be accessed, wherein
• the value of the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal are associated with a thickness of the currently accessed recording layer and the recording layer desired to be accessed.

An optical disk drive comprising:

• a recording layer checking unit configured to check a number of recording layers of an optical disk to which a focal point of an optical signal emitted from a pickup of an optical disk drive has moved, by using a signal produced by processing signals detected by the pickup, and simultaneously move the focal point of the optical signal emitted from the pickup to a recording layer desired to be accessed, according to a layer jump command;
• an aberration correction value and parameter set value changer configured to change an aberration correction value and a gain of a sum signal, a gain of a focus error signal, and/or a balance of the focus error signal that determines characteristics of signals for use in servo control of the optical disk drive, so as to adapt to each of the recording layers from a currently accessed recording layer to the recording layer desired to be accessed, wherein the changing of the value of the gain of the sum signal, the gain of the focus error signal, and/or the balance of the focus error signal is based on an aberration correction amount that is used during the changing of the aberration correction value operation between the currently accessed recording layer and the recording layer desired to be accessed;
• and
• a lookup table comprising the value of the gain of the sum signal, the gain of the focus error signal, and the balance of the focus error signal optimized based on the aberration correction amount between the currently accessed recording layer and the recording layer desired to be accessed.