Recording over 15 ktpi using multichannel heads in a tape system

In magnetic recording systems, it has been reported that sufficient signal-to-noise ratio (SNR) was obtained with a narrow track width, using a spin-valve head and metal-evaporated tape. In order to apply this to a helical-scan tape system, techniques for writing narrow tracks and reading them exactly were required. However, the degree of mechanical accuracy demanded was too high to realize. With this in mind, we have developed multichannel heads which can write and read certain tracks with a single scan, as well as a nontracking technique removing the need for such precise mechanical accuracy. A prototype tape drive employing these techniques was developed, and a track density exceeding 15 ktpi was achieved.