Lesekopf

Lesekopf, in German technical literature, refers to the read head component of data storage devices. The term is often used as part of the broader Lese-/Schreibkopf (read–write head) assembly found in magnetic storage devices such as hard disk drives (HDDs) and magnetic tape drives. The Lesekopf’s primary function is to convert the magnetic state of the storage medium into an electrical signal that can be processed into user data.

In HDDs, the read head is an extremely small sensor mounted on an actuator arm that flies just above the rotating disk surface on a self-generated air bearing. Reading relies on magnetoresistive sensors, such as AMR, GMR, or TMR elements, which detect changes in magnetic flux corresponding to data bits. The detected signal is amplified and decoded by the read channel to reconstruct the stored data. Modern read heads are designed for high sensitivity, low noise, and resilience to write-induced magnetic interference, enabling higher data densities and speeds.

The term Lesekopf can also appear in the context of optical storage, where an optical read head (laser, objective, and photodetector) detects reflected light modulated by the disc’s pits and lands. In everyday usage, however, “Lesekopf” most commonly denotes the magnetic read element within the read–write head of magnetic drives.

History and evolution notes that magnetic read heads have progressed from inductive sensing to magnetoresistive technologies, significantly increasing data density and reliability. Although packaging and materials have changed, the basic role of the Lesekopf as the data-retrieving element remains central to magnetic storage systems.