Optical Recording of Servo Pattern on Magnetic Discs
Original Publication Date: 1984-Dec-01
Included in the Prior Art Database: 2005-Feb-05
The introduction of an optical servo track onto magnetic discs offers an advantage over magnetic servo. This advantage stems from the non- interference of the optical track with the magnetic track and the resulting higher information density that it is possible to record magnetically. This disclosure proposes a high-gain, simple photographic method as a way of obtaining the optical pattern required. The free-radical photographic method proposed is very efficient and convenient to use. Its features are: low energy (10-20 ergs per square centimeter at 4400 A), dry working, development by red radiation, and fixing by controlled heat.