Patent ID: 6934100

Claim:
A method of measuring non-linearity in the magnetic recording/reproduction of a medium comprising the steps of: measuring a first predetermined harmonic component from the reproduced signals of the reference signals magnetically recorded in a medium; measuring a second predetermined harmonic component from the reproduced signals for each of the plural kinds of to-be-measured signals magnetically recorded in said medium; and calculating a non-linear transition shift NLTS in the magnetic recording/reproduction from said first predetermined harmonic component and from said second predetermined harmonic component corresponding to each of the to-be-measured signals, wherein said harmonic component of said first and second predetermined harmonic components is a fifth harmonic component, wherein said reference signals are the ones obtained by cyclically and serially shifting, from an optional bit, the data of a bit-string pattern for magnetically recording the data into said medium by once effecting the magnetization and demagnetization for the same period of time, respectively; and wherein said plural kinds of predetermined bit-string patterns include: a first pattern of bit strings each including a tribit in which the magnetic inversion occurs continuously for three bits in each period of said magnetization and demagnetization; a second pattern of bit strings each including 2T in which the magnetic inversion occurs after an interval of two bits in each period of said magnetization and demagnetization; and a third pattern of bit strings including a bit constitution HTS in which the magnetic inversion occurs in a manner that the magnetization occurs in a direction opposite to the direction of magnetization of the record in the medium.