FLY HEIGHT CONTROL OVER PATTERNED MEDIA

摘要

A fly height of a read/write head (126) in a disc drive is actively controlled as the read/write head is positioned over a rotating disc (134) with a patterned media (208). The patterned media includes ridges (310) and grooves (320) in servo wedges in the patterned media. An estimated fly height of the read/write head is compared with a desired fly height to generate a control signal. The control signal is used to apply a voltage difference across a piezoelectric layer joining the read/write head to a slider to move the read/write head. A map of ridges and grooves in the patterned media is generated and the fly height of the read/write head is actively controlled based on information in the map.