OPTICAL RECORDING MEDIUM

摘要

PURPOSE:To expand the information quantity of an information region by reducing the servo region of the optical recording medium to or from which recording or reproducing is executed by a focused light beam. CONSTITUTION:This optical recording medium 101 has spiral or concentrical track center lines 104 and is provided with plural clock marks 105a to 105i at intervals of the same angle on the circumference. The lines connecting the center lines of the adjacent tracks are radial around the center. First wobble marks 106a to 106i and second wobble marks 107a to 107i which are displaced respectively inward and outward with respect to the center lines of the tracks are so disposed that the central angle to view the clock marks and the first wobble marks and the central angle to view the first wobble marks and the second wobble marks respectively vary with each of the servo zones and that the central angles are smaller nearer the servo zones of the outer periphery.