Detection and measurement of position error signal linearity in timing based servo patterns using differential nonlinearity

A computer system for measuring position error signal nonlinearity in timing based servo patterns, comprising:

• a machine capable of executing instructions embodied as software;
• a plurality of software portions of the software, wherein one of said software portions is configured to collect a set of servo pattern position error signal readings at two or more locations along a servo stripe;
• one of said software portions is configured to determine a differential position error signal from the set of servo pattern position error signal readings at each of the two or more locations along the servo stripe;
• one of said software portions is configured to examine the differential position error signal at the two or more locations along the servo stripe so as to isolate error associated with systematic position error signal readings from error associated with nonsystematic position error signal readings;
• and
• one of said software portions is configured to measure nonlinearity of the differential error associated with systematic position error signal readings at the two or more locations along the servo stripe.

At least one computer-readable medium containing a computer program product for measuring position error signal nonlinearity in timing based servo patterns, the computer program product comprising:

• program code for collecting a set of servo pattern position error signal readings at two or more locations along a servo stripe;
• program code for determining a differential position error signal from the set of servo pattern position error signal readings at each of the two or more locations along the servo stripe;
• program code for examining the differential position error signal at the two or more locations along the servo stripe so as to isolate error associated with systematic position error signal readings from error associated with nonsystematic position error signal readings;
• and
• program code for measuring nonlinearity of the differential error associated with systematic position error signal readings at the two or more locations along the servo stripe.