Patent ID: 8243390
Filing Date: 2012-08-14
Classification: G11B

Abstract:
1. A method for reading magnetic state transitions in a two-layer continuous magnetic medium comprising two magnetic layers, each magnetic layer comprising magnetic material continuously distributed in an X-Y plane defined by an X direction and a Y direction orthogonal to each other, said two magnetic layers separated by non-magnetic spacer material and distributed along a Z direction orthogonal to the X-Y plane, said method comprising: reading at a specific location (x) of the medium along the X direction, by a magnetic read head moving in the X direction, a readback pulse shape W(x) associated with a magnetization state transition T after said reading W(x), identifying from W(x), a set (T) of magnetization state transitions, wherein either 1) the set (T) consists of T if the set T comprises T identifying the magnetization state transition T displaying and/or recording the identified magnetization state transition T