| 摘要 |
PURPOSE:To obtain a polishing method which polishes a blocks provided with plural thin film magnetic heads up continuously to a necessary extent without interruption and has the polishing precision of gap length irrelevant to the structure of the block. CONSTITUTION:In polishing the block, e.g. in lapping, while the lapping advances, the distance between a surface being lapped and a desired finished surface is measured by a measuring means 15. A signal value from the means 15 is supplied to a control circuit 13, which supplies control signals for uniform lapping to respective rod driving parts 11. For example, when electrostatic capacity C1 is greater than electrostatic capacity C2, the extent of lapping is less on the side where the electrostatic capacity C2 of the block 2 is obtained and a signal S1 showing its gradient is generated by a differential amplifier 24; and a differential amplifier 25 receiving the signal S1 generates a signal W1 generated by weakening a signal supplied to a voice coil, thereby reducing a load on a rod 10 by the voice coil 29. |
