Magnetic signal distribution in disk drives

This work present an overview of the application of high resolution magnetic read back mapping within a functioning production disk drive. It is demonstrated how magnetic or mechanical media defects can be visualized and discriminated against each other and how track squeeze effects and servo pattern layout/integrity can be studied. Examples are given where only the native data signal is used for the analysis or how additional over writing is used to gain further information. Like in many other fields, the visualization of specific features enhances and contributes to the understanding of underlying mechanism.