A magnetic sensor using giant magnetoresistance(GMR) comprises an insulating layer formed on a lower terminal layer and having a contact hole; a GMR layer formed in a region including the entire contact hole and part of the insulating layer surrounding the contact hole; and an upper terminal layer. This sensor is compact and easy to manufacture, and has a large rate of change in resistance.
A buffer layer is arranged on the main surface of a support substrate, and includes either substance selected from CoFe, cobalt or copper. A multilayer gigantic magnetic resistance(GMR)layer with a laminated construction is arranged on the buffer layer, and is obtained by the intermediate laminating of magnetic layers and nonmagnetic layers. The nonmagnetic layers are copper. The magnetic and the nonmagnetic layers are sufficiently thickness to demonstrate the gigantic magnetoresistance effect. The thickness of the buffer layer differs from the thickness of each of the layers that form the multilayer GMR layer.
A magnetic sensor having such a structure that a hard layer for controlling the magnetic domain formed of a conductive hard magnetic material, and a magnetic sensor layer, are at least partially in direct contact with each other, and current flows in the direction wherein at least a main component of current is perpendicular to the surface of the magnetic sensor layer. The current flowing in the magnetic sensor layer and the hard layer is controlled by changing the resistivity of the hard layer. The magnetic sensor is used as a magnetic read head in a magnetic recording apparatus such as magnetic disk apparatus.
A magnetoresistive element that detects a change of magnetoresistance by giving a sense current in the thickness direction of a magnetoresistive effect film including at least a base layer, a free layer, a non-magnetic layer, a pinned layer, a pinning layer, and a protection layer, includes a granular structure layer that includes conductive particles and an insulating matrix material in the form of a thin film containing the conductive particles in a dispersed state and having a smaller thickness than the particle diameter of the conductive particles, the granular structure layer being interposed between at least two adjacent layers among the base layer, the free layer, the non-magnetic layer, the pinned layer, the pinning layer, and the protection layer.
A low inductance electrical spring connector(162) is used on a printed circuit board(168) of a disc drive(100). The spring connector interconnects conductors(152) of a flex circuit(150) extending through a basedeck(104) of the disc drive to conductive traces(170) of the printed circuit board supported on an exterior surface of the basedeck. The spring connector has a dielectric housing(164) which forms an insertion cavity(176). Conductive spring contacts(166) are provided, each having a first end(186) extending from the dielectric housing and a second end(180) confined by the dielectric housing. The first ends are attachable to the conductive traces of the printed circuit board and the second ends are pre-load contact portions having respective contact surfaces extending into the insertion cavity to engage the conductors of the flex circuit.
An apparatus and method is used for improving disc drive data storage capacity and seek performance. A disc drive includes a rotatable disc with a recording surface on which a plurality of tracks are defined and an actuator which supports a head adjacent the tracks. A servo circuit uses a velocity profile to position the head adjacent a destination track, with the servo circuit adaptively selecting the velocity profile in relation to the physical location of the destination track. The servo circuit preferably uses a reduced maximum velocity and a decreased deceleration rate when the deceleration track is adjacent an innermost or outermost diameter of the disc, thereby reducing the risk of damage as a result of contact between the actuator and a latch/stop used to limit radial excursion of the head.
The invention relates to a method for the recording and reading of data with a holographic write/read apparatus onto a holographic recording medium with a thin holographic recording layer. The medium is preferably an optical card(2). The recording of the information is in the form of data pages stored as thin Fourier holograms(61). According to the invention, it is foreseen to use reflected transmission and polarisation holography with different write and read wavelengths, and to correct during reading the distortion in the readout channel caused by the difference between the write and read wavelengths. The invention further relates to an apparatus and system for performing the method. The present invention also discloses a method of coding the recorded information.
