| 摘要 |
PURPOSE:To effectively increase track density and to increase recording capacity in a diskcoid recording medium performing the positionings of data tracks using grooves formed on circumferences for the tracking servo of an opptical position detecting system. CONSTITUTION:Respective two lines of data tracks 5, 5 are arranged in between a groove 4 and a groove 4 adjacent to the groove 4 formed on circumferences for the tracking servo. These data tracks are arranged in the same manner with respect to both surfaces of the front and rear sides of the diskcoid recording medium. Heads 6, 7 in which optical sensors 8, 9 are incorporated respectively are arranged by being placed opposite to respective surfaces of the recording medium. The positions in a horizontal direction of the sensor 9 for the front side and the sensor 8 for the rear side are shifted by a space (a). The space (a) is set to be the same as the space (b) of two lines of data tracks placed in between grooves. |
