Patent ID: 7848046

Claim:
A magnetic disk apparatus, comprising: a magnetic disk comprising magnetic dot lines each including magnetic dots arrayed at equal intervals in a down track direction; and a read/write head which uses a plurality of adjacent magnetic dot lines as one track and sequentially performs read and write on the magnetic dots included in the magnetic dot lines constituting the track, wherein N lines of magnetic dot lines are used as one track in the magnetic disk, and wherein, assuming that a track pitch is T, a bit pitch at zero skew angle is B, and a skew angle is θ, the magnetic dots included in each magnetic dot line are arrayed at a pitch NB in the down track direction, and the magnetic dots included in an n-th magnetic dot line in each track are displaced in the down track direction from the magnetic dots included in a 0-th magnetic dot line in the track by a displacement represented by the following formula: B−(Tn/N)tan θ, where n is an integer from 0 to N-1.