US Patent 7839588 Method of alternating track write for defect identification

Defects are identified in a disk drive by first writing a pattern of tracks to a disk surface in the disk drive, the pattern of tracks including written tracks alternating with unwritten tracks. The written tracks of the pattern of tracks are read, and a defect in a portion of a first written track is detected. An unread portion of a first unwritten track is then identified as comprising a defect based at least in part on the defect in the first written track, the first unwritten track located proximate the first written track.