| 摘要 |
PURPOSE:To eliminate a surface void of a final shape, and to prevent a recording medium from being damaged due to the void by collecting the void in an embedded nonmagnetic material of a track width control part, to the center, and cutting its part. CONSTITUTION:A glass material is placed on the upper part of the second core, heated to a glass melting point, glass is packed in a groove for controlling a track width, and also three cores 25, 26 and 27 are brought to glass bonding. Also, in case of this bonding, a prescribed load is applied from both side faces 28, 29 of the first core and the third core and fixed with a jig so that a correlative position of a track is not shifted. At the time of this bonding, a void is generated, but by setting a pitch =P and a track width =Tw, it is collected to the center of a range of (P-Tw) of a groove part 14. In this state, by cutting its part, a surface void of a final shape is eliminated, and a damage of a recording medium due to the void can be prevented. |
