| 摘要 |
<p>PURPOSE:To eliminate write errors, and to elevate reliability, by detecting a physical defect by a reflected ray from a tape before writing of a magnetic tape, and constituting so that writing of data to the defective part is prevented. CONSTITUTION:When writing, a reflected ray of a projector 11 is converted to an electric signal 13 by a photodetector 12. Due to a physical defect of a tape, the electric signal 13 is varied. A defect detecting part 14 detects this variation and outputs a defect detecting signal 15. A distance between a position B of a gap of a head 6 and an irradiating position A is larger than writable maximum block length. Accordingly, before a writing instruction, when a defect detecting signal is not outputted at the previous writing time, writing can be started immediately. When the defect detecting signal is outputted at the previous writing time, writing of data is inhibited, instead of which its corresponding length is skipped by an erasing signal. The skip is executed until it runs between A and B after the defect detecting signal has been annihilated, and after that, the data is written by a writing signal 5.</p> |
