KEY ISSUES IN THE DESIGN OF MAGNETIC TAPES FOR LINEAR-SYSTEMS OF HIGHTRACK DENSITY

Areal densities for data tape systems have been increasing exponential ly ever since the first product introduction in the early 1950's, Incr eases in linear density have provided the major part of the increases in recording density. Now, however, the time has come to push harder o n track densities. The signal-to-noise issues for higher track densiti es are relatively well understood. However, the use of full-time track following, with multi-channel heads, adds additional issues to the li st of tape design objectives for future systems of very high track den sity. The ultimate drive error performance, will now be Impacted by la teral tape motion, relative azimuth angle between tape and head, and t rack spacing variation due to dimensional changes in the tape. Control ling lateral tape motion and relative azimuth angle requires improveme nts in tape edge quality, the overall tape-path design, and the writin g of the original servo signals on the tape. Controlling the track spa cing problem will require better understanding of tape dimensional sta bility and how it is influenced by environmental changes, by pack stre sses, and by tape design and processing. We conclude with suggestions of how to achieve the improvements necessary to stay on the required a real density trend line.