| 摘要 |
PROBLEM TO BE SOLVED: To detect a header position by using bit-patterned media and servo sector null patterns thereof. SOLUTION: A patterned recording media comprises a segment and a null pattern formed in the segment. The segment comprises first and second rows of discrete magnetic elements separated by a non-magnetic material, and a row of non-magnetic material positioned between the first and second rows. The null pattern comprises consecutive groups of the discrete magnetic elements in the first and second rows of the segment. Each group in the first row has a magnetic polarity that is opposite the magnetic polarity of adjoining groups in the first row. Each group in the second row has a magnetic polarity that is opposite the magnetic polarity of adjoining groups in the second row. The sums of readback signals of the consecutive groups of the discrete magnetic elements are determined for first and second rows, to generate a demodulated position signal corresponding to the header position based on the subtraction of them. COPYRIGHT: (C)2011,JPO&INPIT |
