Patent ID: 6747830
Filing Date: 2004-06-08
Classification: G11B

Abstract:
A perpendicular magnetic recording/reading apparatus comprising a perpendicular magnetic recording medium including a nonmagnetic substrate, and a magnetization fixing layer for a backing layer, a soft magnetic backing layer, and a perpendicular magnetic recording layer formed in the order on said nonmagnetic substrate,wherein a maximum external magnetic field of a magnetic recording medium longitudinal component which is applied to said perpendicular magnetic recording medium is smaller than an absolute value Hn of a magnetic field at an intersection of a straight line connecting two points of an M-H curve in the longitudinal direction of said soft magnetic backing layer and a tangent of the M-H curve, one of the two points being a point (Hs, Ms) at which magnetization saturates in the first quadrant, the other of the two points being a positive intersection (0, Mr) of the M-H curve and the ordinate, and the tangent being at a negative intersection (âˆ’Hc, 0) of the M-H curve and the abscissa, and the maximum external magnetic field of the magnetic recording medium longitudinal component which is applied to the outermost perimeter of a recording area of said perpendicular magnetic recording medium is smaller than the Hn of said soft magnetic backing layer.