Interferometric measurement of head/tape spacing in a high-speed R-DAT helical recorder

Head/tape spacing in a high-speed R-DAT helical recorder was interferometrically measured using a replica head made of fiber-optic material. For the head tested, observation of white light fringes indicates that the region where head/tape spacing is less than 100 nm changes significantly as a function of tape tension in the range of 0.05 to 0.15 N. However, the small spacing region was not significantly affected by changes in scanner speed in the range from 2000 to 100000 RPM.<
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