Abstract: A sliding spline shaft device of the present invention includes a male spline and a female spline that is fitted to the male spline in an axially slidable manner, and at least one of the splines has a surface processed layer. The surface processed layer includes an undercoat layer, an intermediate layer containing phosphate, and a topcoat layer containing solid lubricant, in this order. The undercoat layer contains iron nitride and/or iron carbide. Thus, the surface of a base material has high hardness. As a result, microscopic deformation of the sliding surface is reduced, and increase in a real contact area is suppressed, whereby stick-slip is prevented.

Abstract: Embodiments of the present invention provide a magnetic head inspection system having a simple configuration capable of inspecting magnetic heads. According to one embodiment, the magnetic head inspection system comprises an inspection module which is provided with a magnetic disk where servo data including track identifier information are recorded, a spindle motor, a carriage having a mount structure to which a head assembly containing a magnetic head is secured, a voice coil motor and a main circuit section. An inspection circuit section instructs the main circuit section to execute control so as to move the magnetic head to a specific track and perform a certain read write operation by the magnetic head in order to inspect the magnetic head.

Abstract: Embodiments of the invention provide a method for setting a light source parameter in order to recognize an identification mark on an object surface. In one embodiment, a grayscale image is generated by setting the light volume of the light source to a given value. Plural thresholds each for binarizing the grayscale image in density are set. The inter-class variance values to be produced respectively according to the thresholds are calculated and the largest inter-class variance value is selected as the peak inter-class variance value from the inter-class variance values calculated. The light volume is changed to a plurality of different values. Peak inter-class variance values are obtained respectively for the values and the largest peak inter-class variance value is selected as the maximum inter-class variance value from the peak inter-class variance values obtained.

Abstract: Embodiments of the present invention set the resistance value and resistance change of a magnetoresistive element as the comparison criteria of a tester without use of an actual magnetic head slider in an inspection process during fabrication of magnetic head sliders. According to one embodiment, at the time of default setting of a tester, an emulator is connected to a preamplifier of a magnetic characteristic measurement device. Signals which are obtained by emulating the resistance value and resistance change of the magnetoresistive element are inputted to the preamplifier from the emulator. The resistance value and resistance change serve as references. The output of the preamplifier is A/D converted to be inputted to the MPU. In the MPU, the A/D converted output is converted into a resistance value to be stored in the ROM. The tester uses the resistance value stored in the ROM as a reference to compare the measured resistance value of the magnetoresistive element therewith.

Abstract: Embodiments of the present invention provide a magnetic head inspection system having a simple configuration capable of inspecting magnetic heads. According to one embodiment, the magnetic head inspection system comprises an inspection module which is provided with a magnetic disk where servo data including track identifier information are recorded, a spindle motor, a carriage having a mount structure to which a head assembly containing a magnetic head is secured, a voice coil motor and a main circuit section. An inspection circuit section instructs the main circuit section to execute control so as to move the magnetic head to a specific track and perform a certain read write operation by the magnetic head in order to inspect the magnetic head.

Abstract: Embodiments of the invention provide a method for setting a light source parameter in order to recognize an identification mark on an object surface. In one embodiment, a grayscale image is generated by setting the light volume of the light source to a given value. Plural thresholds each for binarizing the grayscale image in density are set. The inter-class variance values to be produced respectively according to the thresholds are calculated and the largest inter-class variance value is selected as the peak inter-class variance value from the inter-class variance values calculated. The light volume is changed to a plurality of different values. Peak inter-class variance values are obtained respectively for the values and the largest peak inter-class variance value is selected as the maximum inter-class variance value from the peak inter-class variance values obtained.