Ampex Corporation

Other

Minnesota Mining and Manufacturing Company

David H Davies

Beverley R Gooch

Thomas M Coughlin

Daniel E Evanicky

A magnetic storage system includes a magnetic storage medium comprising a keeper layer of relatively low permeability soft magnetic material deposited upon a magnetic storage layer or between multiple magnetic storage layers. The low permeability keeper layer may be disposed either above or below the magnetic storage layer. In the unsaturated state, the keeper layer acts as a shunt path for flux emanating from recorded transitions on the magnetic storage layer, producing an image field of the recorded transitions in the keeper. This shunt path prevents signal flux emanating from the recorded transitions from reaching the head. To read data from a recorded transition on the magnetic storage layer; a bias current is applied to windings of the head, creating a bias flux which saturates a portion of the keeper layer. Once saturated, this portion of the keeper can no longer shunt flux emanating from the recorded transition, which is the region represented by the head reproduce transducer.

Magnetic storage and reproducing system with a low permeability keeper

A magnetic storage system is disclosed that includes a magnetic storage layer associated with a soft magnetic saturable keeper layer. A transducer is spaced from the storage layer and the keeper layer in flying relationship thereto, with an MR element contained therein to provide high sensitivity detection along with the reduced spacing loss available from the keepered storage layer.

Magnetic recording system having a saturable layer and detection using

The flexible, particulate magnetic storage medium includes a substrate and a magnetic storage layer of hard magnetic particles held within a binder. The flexible, particulate magnetic storage medium also includes a soft magnetic keeper layer. The soft magnetic keeper layer may be established by coating the individual hard magnetic particles of the magnetic storage layer with a layer of soft magnetic material to establish a 'keeper layer' around each particle. A break layer of non-magnetic material may be provided between the hard and soft layers. The individual particles are coated by methods such as in situ precipitation. The soft magnetic layer may also be established by providing a separate layer of soft magnetic material within a binder of cross linkable resins. The resulting flexible, particulate magnetic storage medium is a laminate principally comprising a substrate, a first layer of hard magnetic particles within a binder, and a second layer of soft magnetic particles also within a binder. The laminate medium may be produced through extrusion of binder particle mixes through multi aperture slot die extensions. The flexible, particulate magnetic media may be used in tape or flexible disc formats.

Particulate magnetic medium utilizing keeper technology and methods of

A magnetic storage system includes a magnetic storage medium comprising a keeper layer of relatively low permeability soft magnetic material deposited upon a magnetic storage layer or between multiple magnetic storage layers. The low permeability keeper layer may be disposed either above or below the magnetic storage layer. In the unsaturated state, the keeper layer acts as a shunt path for flux emanating from recorded transitions on the magnetic storage layer, producing an image field of the recorded transitions in the keeper. This shunt path prevents signal flux emanating from the recorded transitions from reaching the head. To read data from a recorded transition on the magnetic storage layer, a bias current is applied to windings of the head, creating a bias flux which saturates a portion of the keeper layer. Once saturated, this portion of the keeper can no longer shunt flux emanating from the recorded transition, which is the region represented by the head reproduce transducer.

An apparatus and method for retrolasing plaque deposits in a coronary artery to remove same includes a tip assembly on the end of a flexible inner tube containing optical fibers that are slidable along a guide wire. The tip assembly includes a reflective surface rearwardly of a front face that directs laser energy supplied through the optical fibers in a rearward direction through a window portion to a focal point externally of the tip assembly. The deposit is removed as the tip assembly is moved in a rearward progression back through the deposit.

Retrolasing catheter and method

A cover assembly for use with a disk-shaped optical recording medium, having two substantially identical halves, each having an inner surface adapted to provide upon assembly with the medium an air gap adjacent an optical recordable coating on the medium. Each cover half is transparent and has substantially no birefringent characteristics on the region overlying the air gap, thus allowing light to pass unimpeded therethrough. The cover assembly is adapted to be coupled to the central hub of the optical recording medium and to have a raised annulus adjacent thereto to support the assembly and minimize contact with the transparent portion.

Growing community of inventors

Cupertino, CA, United States of America

David H Davies