Patent ID: 7248424

Claim:
A nonlinearity measuring method of calculating non linear transition shift (NLTS) in magnetic recording/regenerating in a medium, comprising: a recording step of a reference signal to record a reference signal on the medium; a recording step of signals to be measured to record plural kinds of signals to be measured on the medium, a first measuring step to measure a first predetermined higher harmonic component from a regenerated signal of the reference signal magnetically recorded on said medium; a second measuring step to measure a second predetermined higher harmonic component from its regenerated signal with respect to each of the plural kinds of signals to be measured magnetically recorded on said medium; and a calculating step to calculate the NLTS from said first predetermined higher harmonic component and said second predetermined higher harmonic component corresponding to each of the signals to be measured, wherein each of said plural kinds of signals to be measured includes a magnetization inversion pattern string P 1 preceding objective bits to be measured of said NLTS.