| 摘要 |
PURPOSE:To make the interval of a servo track narrow, to make servo information high-density by forming accurately servo information, which is written on the servo face of a magnetic disk, concentrically with a shaft as a center. CONSTITUTION:When the center of a magnetic disk 4 is matched to a shaft 12 to set the magnetic disk 4 to a spindle 3 and servo information is written on the servo face, a laser 8 is radiated from a laser length measurer 5 to the mirror 7 of a head positioner 6, and actual measured length data is obtained by its reflected laser and is inputted to a converter 19, and the deflection of the shaft 12 is measured by a sensor 15, and a correcting value is given to programmed pitch data from a CPU18 through a filter 16 by a summing amplifier 17, and this data is inputted to the converter 19 and is compared with the actual measured length from the laser length measurer 9, and the result is inputted to a digital-analog converter 20 and is inputted from an integrator 21 to a servo amplifier 22 to operate a voice coil 7, and thus, servo information having the same center as the magnetic disk 4 is always written on a servo face 13. |
