Overwrite characteristics in partial penetration recording

The critical medium coating thickness for saturation recording and partial-penetration recording was experimentally investigated. It was found that less than about 0.4- mu m coating thickness is necessary for saturation recording at 35 kFRPI. The effects of overwrite modulation (OWM) on recording characteristics were also examined. OWM affected peak-shift in the saturation recording, and extra bits were produced in the partial-penetration recording. A pre-erase method, which is suitable for partial-penetration recording, is discussed.>