High-density magnetic recording tracking method using a laser diode (and dual-stage actuator)

A novel tracking technology for achieving high track density over 10 k tracks-per-inch (TPI) is developed. Two key technologies are incorporated. One is the application of optical disk technology to a magnetic disk to obtain a high-quality servo signal with a trackwidth 1.5 to 2 mu m. The other is the installation of a dual-stage actuator using a piezoelectric device for the fine actuator to gain higher servo performance in a bandwidth greater than 1 kHz. The authors describe the design of the optical servo system for the track pitch 1.5 mu m, 17 kTPI, and experimental results including a comparison of magnetic heads.<
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