Spin-Stand Imaging of Perpendicularly Recorded Data

The spin-stand imaging technique is further extended to use the pre-existing servo marks on commercial hard disk media for greater scanning precision, which is necessary for track densities above 100 kilo-tracks-per-inch. This reduces the nonrepeatable run-out due to spindle vibration that can significantly distort spin-stand images acquired from commercial disks removed from their native environments. By driving a piezoelectric transducer with feedback derived from the prewritten servo marks, greater accuracy is achieved and demonstrated. Additionally, a technique for measuring the spin-stand imaging head response function and its application for imaging of recorded bit patterns in the context of perpendicular recording is described.