Abstract: This light detection element includes a meta-lens that includes nanostructures which are two-dimensionally arranged; and a magnetic element that includes a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer. Light which passes through the meta-lens is applied to the magnetic element.

Abstract: The magnetic sensor of the invention comprises a base portion, a sensor chip positioned on the base portion, a wiring portion adapted to electrically connect a terminal of the sensor chip to a connecting lead, a resin having a low elastic modulus for coating at least the sensor chip, and a resin having a high elastic modulus for coating at least the low elastic-modulus resin and the wiring portion, wherein the sensor chip includes a magneto-resistive effect device, and the low elastic-modulus resin has an elastic modulus ranging from 10 kPa to 80 MPa while the high elastic-modulus resin has an elastic modulus of 1 GPa or more, and enables the sensor chip to perform well in a good state although having a structure of sealing up the sensor chip with the resin member.

Abstract: The magnetic sensor of the invention comprises a base portion, a sensor chip positioned on the base portion, a wiring portion adapted to electrically connect a terminal of the sensor chip to a connecting lead, a resin having a low elastic modulus for coating at least the sensor chip, and a resin having a high elastic modulus for coating at least the low elastic-modulus resin and the wiring portion, wherein the sensor chip includes a magneto-resistive effect device, and the low elastic-modulus resin has an elastic modulus ranging from 10 kPa to 80 MPa while the high elastic-modulus resin has an elastic modulus of 1 GPa or more, and enables the sensor chip to perform well in a good state although having a structure of sealing up the sensor chip with the resin member.

Abstract: The invention is directed to a magnetic head driving circuit and a magnetic disk device which achieve a low flying-height with thermal protrusion and thus a reliable write operation on the magnetic disk. The write circuit 3 receives the write data signal Sw inputted therein, and generates and outputs the write voltages Wx, Wy based upon the inputted signal. The write voltages Wx, Wy are composed of a preamble portion T1, a sink mark T2 and a user data portion T3 in each sector for magnetic recording. In the write voltage, the frequency f2 of the signal in the preamble portion T1 is higher than half the frequency f1 of the signal in the user data portion T3.

Abstract: The present invention provides a thin film magnetic head realizing the gradient and the strength of a perpendicular magnetic field increased as much as possible. A main magnetic pole layer is made recede from a write shield layer. As compared with the case where the magnetic pole layer is not receded from the write shield layer, an overlap range in which the main magnetic pole layer and the write shield layer are overlapped one another is smaller. Accordingly, the amount of magnetic flux emitted from the main magnetic pole layer toward a recording medium relatively increases, and the amount of magnetic flux leaked from the main magnetic pole layer to the write shield layer relatively decreases.

Abstract: The invention is directed to a magnetic head driving circuit and a magnetic disk device which achieve a low flying-height with thermal protrusion and thus a reliable write operation on the magnetic disk. The write circuit 3 receives the write data signal Sw inputted therein, and generates and outputs the write voltages Wx, Wy based upon the inputted signal. The write voltages Wx, Wy are composed of a preamble portion T1, a sink mark T2 and a user data portion T3 in each sector for magnetic recording. In the write voltage, the frequency f2 of the signal in the preamble portion T1 is higher than half the frequency f1 of the signal in the user data portion T3.

Abstract: A property improving method includes first and second steps. In the first step popcorn noise in a read signal of a thin-film magnetic head is measured so as to determine whether the popcorn noise falls within a permissible range. In the second step a current is fed to the recording head of the thin-film magnetic head, the current having a value greater than that of the current fed when a normal writing operation is performed. While the value of the current fed to the recording head is gradually increased in the second step, the first and second steps are alternately repeated until it is determined that the popcorn noise falls within a permissible range in the first step, or the current value reaches a specific upper limit.