| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To detect running speed of a magnetic tape with a simple configuration and high accuracy. <P>SOLUTION: A servo writer is provided with a writing head upstream on a running path of the magnetic tape, and a reading head downstream thereon, respectively. The writing head has a tilt in the running direction of the magnetic tape, and two parallel linear magnetic gaps are established. A servo pattern SP is written in the running magnetic tape by periodically outputting recording pulse current to this writing head. The reading head senses the recorded servo pattern SP to output a servo signal. With this servo signal, the running speed v of the magnetic tape MT is obtained by arithmetic operation from a time interval A obtained from two parallel linear patterns Bb1, Bb2 and a time interval B obtained from adjacent servo patterns SP. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
