Method for optically encoding digital data on a substrate and the data record carrier formed thereby

摘要

A method for optically encoding digital data (12) on a substrate (11) without timing or synchronization data to form a data record carrier (10) includes the steps of: selecting a track (14) path on the substrate (11); selecting a data cell length (L) in the direction of the track (14) for each bit of data to be stored in each cell (15) on each track (14); selecting a cell width dimension (W) transverse to the direction of the track (14); selecting an optical non-transition cell (15) for one form of logic (0 or 1) to be stored in each such non-transition cell (15); selecting an optical transition cell (15) for the other form of logic (1 or 0) to be stored in each such other transition cell (15); creating at least one track (14) of digital data (12) on the substrate (11) comprised of a series of cells (15) each having the same cell length (L) in the direction of the track (14); establishing in each non-transition cell (15) on the substrate (11) a fully reflective or transmissive surface or a fully non-reflective or non-transmissive surface; establishing in each transition cell (15) on the substrate (11) a reflective or transmissive surface over part of the cell (15) extending transverse to the direction of the track (14) and a non-reflective or non-transmissive surface over the other part of the cell (15) extending transverse to the direction of the track (14) and creating a plurality of arcuate tracks (14) of cells (15) on the substrate (11) with each track (14) being spaced from an adjacent track (14) by a predetermined distance at a point intermediate the ends of each track (14) and each track (14) having the same radius throughout the arcuate path of said track (14) such that the tracks (14) extend in an arcuate manner across the data record carrier (10) with each track (14) having the same radius and being arranged in a nested manner relative to adjacent tracks (14) along a common centerline.