Abstract: A pole-layer-encasing layer made of a nonmagnetic material is disposed on an underlying layer made of a nonmagnetic conductive material. The encasing layer has a groove that penetrates. A pole layer is disposed in the groove. The pole layer is formed by plating through feeding a current to the underlying layer. A polishing stopper layer made of a nonmagnetic conductive material is disposed on the top surface of the encasing layer. The polishing stopper layer indicates the level at which polishing for controlling the thickness of the pole layer is stopped. The polishing stopper layer has an opening that penetrates, and the edge of the opening is located directly above the edge of the groove located in the top surface of the encasing layer.

Abstract: A method of manufacturing magnetic heads comprises the step of: fabricating a magnetic head substructure by forming a plurality of components of the magnetic heads on a single substrate, wherein a plurality of rows of pre-head portions that will be the respective magnetic heads later are aligned in the substructure; and fabricating the magnetic heads by separating the pre-head portions from one another through cutting the substructure. In the step of fabricating the substructure, a plurality of indicators are formed, each of the indicators serving as a reference for indicating the location of a region ABS in which the medium facing surfaces of the magnetic heads are to be formed.

Abstract: A pole layer has a track width defining portion and a wide portion. The pole layer has: first and second side surfaces located opposite to each other in a first region extending from a medium facing surface to a position at a distance of 10 to 300 nm from the medium facing surface; third and fourth side surfaces located in a second region other than the first region; a fifth side surface located at the boundary between the first and second regions and connecting the first and third side surfaces to each other; and a sixth side surface located at the boundary between the first and second regions and connecting the second and fourth side surfaces to each other. The distance between the first and second side surfaces taken in the track width direction decreases with decreasing distance from the top surface of the substrate.

Abstract: Components of a plurality of magnetic heads are formed on a single substrate to fabricate a magnetic head substructure in which a plurality of pre-head portions are aligned in a plurality of rows. The substructure is cut to separate the plurality of pre-head portions from one another, and the plurality of magnetic heads are thereby fabricated. The surface formed by cutting the substructure is lapped to form a lapped surface. The lapped surface is lapped so as to reach a target position of a medium facing surface. The substructure incorporates first to fourth resistor elements each of which detects the position of the lapped surface. The third and fourth detection elements are located at positions shifted from the first and second resistor elements along the direction orthogonal to the medium facing surface.

Abstract: An occupant detection system includes occupant sensors on each of plural seats, first resistors in connection to each of the occupant sensors with different resistance values, a power supply line that supplies electric power to the sensors and resistors from a power source by connecting those parts and the power source, and a control unit that detects occupancy of each of the plural seats based on an electric current value of the power supply line. The occupant detection system having the above configuration detects the occupancy of each of the plural seats without increasing the number of input terminals on the control unit.

Abstract: A load sensor is provided as a seat sensor that includes a first film formed in a linear shape, a second film formed in the same shape as the first film and arranged facing the first film, sensor electrodes arranged between the first film and the second film facing each other. The electrodes are normally spaced apart from each other and come in contact with each other upon receiving a load. The electrodes are connected to a connector through a conducting portion arranged between the first film and the second film. The seat sensor is disposed on a seat where a large compressive force is applied by a passenger.

Abstract: A seat sensor for detecting that an occupant is seated on a vehicle seat having a back rest portion includes a sensor cell. The sensor cell is disposed on the back rest portion of the vehicle seat. The sensor cell has a plurality of electrodes that are arranged to face with each other. One of the plurality of electrodes contacts another one of the plurality of electrodes to make the sensor cell become conductive when the sensor cell is applied with a load.

Abstract: A seat sensor for a vehicle seat having a seat face portion includes a plurality of sensor cells. One of two electrodes of each sensor cell contacts an other one of the two electrodes to make the each of the plurality of sensor cells become electrically conductive when the each of the plurality of sensor cells is applied with a load. A first one of the plurality of sensor cells is displaced from a second one of the plurality of sensor cells in a longitudinal direction and in a transverse direction of the vehicle. One of the two electrodes of the second one of the plurality of sensor cells is directly and exclusively connected in series with one of the two electrode of the first one of the plurality of sensor cells.

Abstract: A pole layer incorporates: a first portion having an end face located in a medium facing surface; and a second portion having a thickness greater than that of the first portion. A surface of the first portion closer to a substrate is located farther from the substrate than a surface of the second portion closer to the substrate. A surface of the first portion farther from the substrate is located closer to the substrate than a surface of the second portion farther from the substrate. At least a portion of the pole layer is placed in an encasing groove formed in a region extending from a first encasing layer through a second encasing layer to a nonmagnetic metal layer.

Abstract: A method of manufacturing magnetic heads comprises the step of: fabricating a magnetic head substructure by forming components of a plurality of magnetic heads on a single substrate, wherein a plurality of rows of pre-head portions that will be the respective magnetic heads later are aligned in the substructure; and fabricating the magnetic heads by separating the pre-head portions from one another through cutting the substructure. In the substructure first resistor elements and second resistor elements are formed. Each of the first resistor elements has a resistance that varies depending on the location of an end of an MR element located in a medium facing surface along the direction orthogonal to the medium facing surface. Each of the second resistor elements has a resistance that varies depending on the location of an end face of a track width defining portion located in the medium facing surface along the direction orthogonal to the medium facing surface.

Abstract: A thin-film magnetic head for perpendicular magnetic recording comprises a coil, a main magnetic pole layer for performing perpendicular recording, a write shield layer and a write gap layer, wherein the main magnetic pole layer comprises a main pole film portion and a yoke pole film portion. The write shield layer has a first shield film portion for determining a throat height, and the thickness of the first shield layer is smaller than the thickness of the yoke pole film portion.

Abstract: A magnetic layer for writing incorporates: a pole layer having an end face located in a medium facing surface; and an upper yoke layer. A first magnetic layer for flux concentration is connected to the pole layer at a location away from the medium facing surface, and allows a magnetic flux corresponding to a magnetic field generated by a first coil to pass. A second magnetic layer for flux concentration is connected to the upper yoke layer at a location away from the medium facing surface, and allows a magnetic flux corresponding to a magnetic field generated by a second coil to pass. When seen in the direction orthogonal to the interface between the second magnetic layer and the upper yoke layer, this interface is disposed at a location that does not coincide with the interface between the first magnetic layer and the pole layer.

Abstract: A magnetic head comprises a pole layer, a first coil, a second coil, and a shield. The shield incorporates: a first portion located backward of the pole layer along the direction of travel of a recording medium; a second portion located forward of the pole layer along the direction of travel of the recording medium; and two coupling portions. The first portion has an end face located in a medium facing surface. The two coupling portions couple the first and second portions to each other without touching the pole layer. Part of the first coil passes through a space surrounded by the pole layer and the first portion. Part of the second coil passes through a space surrounded by the pole layer and the second portion.

Abstract: According to a WDM optical transmission system of the present invention, wavelength numbers information of a WDM signal light output from an upstream side optical amplifying unit to a transmission path fiber, and signal output level information thereof are transmitted to a downstream side optical amplifying unit utilizing a supervisory control light. In the downstream side optical amplifying unit, a loss (span loss) in the transmission path fiber is computed using the upstream side signal output level information and downstream side signal input level information, so that a gain to be set for a downstream side optical amplifier is calculated based on the computed loss, and also, the gain is corrected based on a difference between a target value of the signal output level computed using the wavelength numbers information and an actual measurement value thereof, so that the optical amplifier is controlled in accordance with the post-corrected gain.

Abstract: A magnetic head comprises: an encasing layer having a groove; a nonmagnetic metal layer that has a sidewall located directly above the edge of the groove and that is disposed on a region of the encasing layer away from the medium facing surface; two side shield layers that have sidewalls located directly above the edge of the groove and that are disposed adjacent to the nonmagnetic metal layer on regions of the encasing layer closer to the medium facing surface than the nonmagnetic metal layer; and a pole layer. The pole layer is placed in an encasing section formed of the groove of the encasing layer, the sidewall of the nonmagentic metal layer, and the sidewalls of the two side shield layers. The two side shield layers have end faces located in the medium facing surface on both sides of the end face of the pole layer, the sides being opposed to each other in the direction of track width.

Abstract: A method of manufacturing magnetic heads comprises the steps of: fabricating a magnetic head substructure by forming components of a plurality of magnetic heads on a single substrate so that a plurality of rows of pre-head portions that will be the respective magnetic heads later are aligned in the substructure; and fabricating the magnetic heads by separating the pre-head portions from one another through cutting the substructure. Indicator sections are formed in the substructure. The indicator sections include first indicators and second indicators. Widths of the first and second indicators are equal in an imaginary surface indicating a target location of the medium facing surfaces. One of the widths of the first and second indicators decreases while the other increases with shifts in position along the direction orthogonal to the medium facing surfaces.

Abstract: A shield incorporates: a first layer, a second layer, a third layer, a first coupling portion, and a second coupling portion. The first layer has: a first surface located in a region of a medium facing surface forward of an end face of a pole layer along the direction of travel of a recording medium; a second surface opposed to the pole layer; and a third surface opposite to the second surface. The second layer touches the third surface. The third layer is disposed in a region sandwiching the pole layer with the first layer. The first coupling portion couples the first layer to the third layer without touching the pole layer. The second coupling portion is located farther from the medium facing surface than the first coupling portion and couples the pole layer to the third layer.

Abstract: A magnetic head comprises a pole layer, a shield layer, a gap layer disposed between the pole layer and the shield layer, and a coil. The shield layer incorporates a first layer, a second layer, a third layer and a fourth layer that are disposed on the gap layer one by one. The first layer has an end face located in a medium facing surface. The second layer has: a first surface located in the medium facing surface; a second surface touching the first layer; and a third surface opposite to the second surface. The third layer touches the third surface of the second layer. An end face of each of the third and fourth layers closer to the medium facing surface is located at a distance from the medium facing surface.

Abstract: A magnetic head comprises a pole layer and first and second coils located in regions sandwiching the pole layer. Each of the two coils is flat-whorl-shaped. The first coil incorporates an inner connecting portion and an outer connecting portion opposite to the inner connecting portion. The second coil also incorporates an inner connecting portion and an outer connecting portion opposite to the inner connecting portion. The inner connecting portion of the first coil is electrically connected to the inner connecting portion of the second coil. The outer connecting portion of the first coil is electrically connected to the outer connecting portion of the second coil, too. In such a manner the two coils are electrically connected to each other in parallel.

Abstract: A method of forming a magnetic head comprises the steps of: selectively exposing through the use of a photomask a photoresist layer unpatterned; forming a pattern for forming a pole layer by developing the photoresist layer after the exposure; and forming the pole layer through the use of the pattern. The photomask includes first to third regions. The first region has such a perimeter that a projection image thereof is shaped along a perimeter of an ideal shape of the top surface of the pole layer. The second region touches the perimeter of the first region, and is located outside the first region. The third region is located inside the first region without touching the perimeter of the first region. The third region suppresses deviation of the pole layer from its desired shape which may be caused by the effect of light reflected while the photoresist layer is exposed.