Disk device and seek control method

A disk device, comprising:

• a medium for recording data;
• a head for reading data recorded in a sector on the medium;
• a memory for registering a position of a sector including a defect;
• and
• the CPU selecting one of the control methods according to a state from a plurality of control for moving the head to a target sector.

A seek control method for moving a head to a target sector on a recording medium, comprising the steps of:

• calculating a seek span using a current track position of the head and a position of a track including the target sector;
• detecting whether or not there is the track including a sector including a projected item in the seek span;
• calculating, when the sector includes the projected item, a period of time A to the track including the sector including the projected item;
• calculating a period of time N for the sector including a projected item to reach a seek locus;
• and
• conducting a particular seek operation when the period of time A is equal to the period of time N.