Patent ID: 7900341

Claim:
A method of manufacturing a hard disk recording device using a patterned medium, the hard disk recording device including the patterned medium which is a disk formed with a pattern serving as a recording unit, and a head for performing recording and reproducing of information to the patterned medium, the method comprising: a first process of manufacturing the patterned medium; a second process of manufacturing the head; and a third process of assembling the hard disk recording device including the patterned medium of the first process and the head of the second process, wherein the first process includes a step of forming a plurality (M) of types of patterned media which are designed according to a specification of the head and have different densities of formation of the pattern serving as the recording unit, the second process includes a step of working and forming the head, a step of measuring a magnetic field size of the head, and a step of classifying the head into a plurality (N) of groups according to a distribution of a variation of the magnetic field size of the head, the third process combines the plurality (M) of types of patterned media and the plurality (N) of groups following a predetermined rule so as to assemble a plurality of hard disk recording devices in which correspondences between the patterned media and the heads are different, and the number (N) of groups of the head is larger than the number (M) of types of the patterned media (M<N).