Method for tracking a read head on a data area on a disk and disk apparatus using the method

A recording and reproducing method for recording and reproducing data on a disk-like recording medium using a head having a read head for reproducing and a write head for recording, said head being moved substantially in a radial direction of said recording medium along an arc-like line, said recording medium having a track comprising a plurality of sectors each having a data area storing data and an identification area storing identification information of the data, said data area being displaced from said identification area due to movement of said head relative to said recording medium, said recording and reproducing method comprising the steps of:

• a) determining a position identification sector which is positioned a predetermined number of sectors ahead of a target sector on which a reading operation is to be performed, said position identification sector being determined based on a table storing a period of time required for performing the offset operation and a predetermined factor representing said period of time;
• b) detecting said position identification sector by said read head;
• c) performing an offset operation of said head after said position identification sector is detected so that said head is moved from a first position to a second position, said read head tracking on said identification area when said head is at said first position and said read head tracking on said data area when said head is at said second position, and ignoring a read error occurring when said head is in said offset operation;
• d) measuring said predetermined factor since said identification sector was detected;
• and
• e) performing a data reading operation when a measured value of said predetermined factor reaches a predetermined value.

A recording and reproducing apparatus for recording and reproducing data on a disk-like recording medium using a head having a read head for reproducing and a write head for recording, said head being moved substantially in a radial direction of said recording medium along an arc-like line, said recording medium having a track comprising a plurality of sectors each having a data area storing data and an identification area storing identification information of the data, said data area being displaced from said identification area due to movement of said head relative to said recording medium, said recording and reproducing apparatus comprising:

• determining means for determining a position identification sector which is positioned a predetermined number of sectors ahead of a target sector on which a reading operation is to be performed, said position identification information being determined based on a table storing a period of time required for performing the offset operation and a predetermined factor representing said period of time;
• search means for detecting said position identification sector by said read head;
• offset commanding means for performing an offset operation of said head after said position identification sector is detected so that said head is moved from a first position to a second position, said read head tracking on said identification area when said head is at said first position and said read head tracking on said data area when said head is at said second position, wherein a read error is ignored during said offset operation;
• measuring means for measuring said predetermined factor since said identification sector was detected;
• read commanding means for performing a data reading operation when a measured value of said predetermined factor reaches a predetermined value.

A recording and reproducing method for recording and reproducing data on a disk-like recording medium using a head having a read head for reproducing and a write head for recording, said head being moved substantially in a radial direction of said recording medium along an arc-like line, said recording medium having a track comprising a plurality of sectors each having a data area storing data and an identification area storing identification information of the data, said data area being displaced from said identification area due to movement of said head relative to said recording medium, said recording and reproducing method comprising the steps of:

• a) determining a position identification sector which is positioned a predetermined number of sectors ahead of a target sector on which a reading operation is to be performed, said position identification sector being determined based on a predetermined factor representing a period of time;
• b) detecting said position identification sector by said read head;
• c) performing an offset operation of said head after said position identification sector is detected so that said head is moved from a first position to a second position, said read head tracking on said identification area when said head is at said first position and said read head tracking on said data area when said head is at said second position, and ignoring a read error occurring when said head is in said offset operation;
• d) measuring said predetermined factor since said identification sector was detected;
• and
• e) performing a data reading operation when a measured value of said predetermined factor reaches a predetermined value.

A recording and reproducing method for recording and reproducing data on a disk-like recording medium using a head having a read head for reproducing and a write head for recording, said head being moved substantially in a radial direction of said recording medium along an arc-like line, said recording medium having a track comprising a plurality of sectors each having a data area storing data and an identification area storing identification information of the data, said data area being displaced from said identification area due to movement of said head relative to said recording medium, said recording and reproducing method comprising the steps of:

• a) performing an offset operation of said head when a data read command is supplied so that said head is moved from a first position to a second position, said read head tracking on said identification area when said head is at said first position and said read head tracking on said data area when said head is at said second position, and ignoring a read error occurring when said head is in said offset operation;
• b) detecting an index signal provided for each track on said recording medium when a predetermined period of time has elapsed since said offset operation was started;
• c) detecting a target sector on which a data read operation is to be performed when said index signal is detected, said target sector being detected by measuring a predetermined factor representing a period of time since said index signal was detected;
• and
• d) performing a data reading operation for said data area of said target sector when said target sector is detected.

A recording and reproducing apparatus for recording and reproducing data on a disk-like recording medium using a head having a read head for reproducing and a write head for recording, said head being moved substantially in a radial direction of said recording medium along an arc-like line, said recording medium having a track comprising a plurality of sectors each having a data area storing data and an identification area storing identification information of the data, said data area being displaced from said identification area due to movement of said head relative to said recording medium, said recording and reproducing apparatus comprising:

• determining means for determining a position identification sector which is positioned a predetermined number of sectors ahead of a target sector on which a reading operation is to be performed, said position identification information being determined based on a predetermined factor representing a period of time;
• search means for detecting said position identification sector by said read head;
• offset commanding means for performing an offset operation of said head after said position identification sector is detected so that said head is moved from a first position to a second position, said read head tracking on said identification area when said head is at said first position and said read head tracking on said data area when said head is at said second position, wherein a read error is ignored during said offset operation;
• measuring means for measuring said predetermined factor since said identification sector was detected;
• read commanding means for performing a data reading operation when a measured value of said predetermined factor reaches a predetermined value.