| 摘要 |
A master tape movable in a closed loop including a pinch roller transfers a mirror image to a slave tape movable in a closed loop including a capstan. A thermomagnetic layer on the slave tape has a Curie temperature above which magnetic information is destroyed and below which magnetic information can be recorded on such layer. The thermomagnetic layer is heated above the Curie temperature, thereby becoming lengthened by thermal expansion just before the slave tape reaches the capstan. A downstream portion of a peripheral surface, preferably defining a cylindrical segment, on a first guide receives a pressurized fluid for sensing the tape tension in accordance with the tape width, distance from the cylinder axis and fluid pressure. An upstream portion of the guide peripheral surface receives a vacuum adjustable to regulate tape tension in response to variations in the pressurized fluid pressure. In regulating the tape tension, the spacing between the slave tape and the peripheral surface at the downstream portion is controlled. The master tape is lengthened by a second guide having the same construction as the first guide to compensate for the slave tape lengthening by the heater and the first guide, thereby producing a mirror image on the slave tape after the slave tape has cooled to the ambient temperature. Each of the master and slave tapes has a particular product of the Youngs modulus, tape width and tape thickness to provide a controlled strain on such tape when the tension on such tape is regulated.
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