Mastering of an Optical Disc with a Data Pattern in the Form of a Metatrack Having Coplanar Parallel Sub-Tracks

摘要

A method and a device for writing data marks to an optical disc or a master disc are disclosed, the data marks to be arranged along at least one metatrack, which is formed by a number of coplanar parallel sub-tracks. The method comprises a step of superposing a rotational motion and a radial motion of the disc and of a writing beam spot on the disc relative to each other. The radial motion comprises a motion component in a first radial direction and periodically repeated jumps in a second radial direction opposite to the first radial direction. The radial motion is a superposition of a) a first radial motion component (18), by which the radial position of the writing beam spot as a function of the angular position with respect to the rotational motion is changed steadily with a first slope, and b) a periodic second radial motion component (20), one period of which, plotted as a function of said angular position, is divided into aa) a first interval (20.1), in which the radial position of the writing beam spot changes with a second slope either in the radial direction of the first radial motion component or in the radial direction opposite thereto, and bb) an adjacent second interval (20.2), in which the radial position of the writing beam spot on the disc changes in a radial direction opposite to that of the superposition of the first (18) and second radial motion components during the first interval (20.1), and with a third slope having an amount larger than the amount of the sum of the first and second slopes. Also disclosed is an optical disc or master disc produced by the method of the invention.