| 摘要 |
PURPOSE: To execute continuous recording and reproducing of information signal of music, etc., without interruption by providing an optical recording medium with groove parts and land parts functioning as tracks at every other (1/odd) round and arranging and forming these parts into a series of spirals. CONSTITUTION: The groove parts 1 and the land part 2 are alternately formed at every other round and are arranged and constituted as a series of the spirals from the inner circumferential side toward the outer circumferential side. Both of the width of the groove parts 1 and the width of the land parts 2 are 0.8μm. The track pitch is 0.8μm. The groove parts 1 and the land parts 2 are so arranged and constituted that the central position of the irradiation with a light beam deviates by 0.8μm to the outer circumferential side in the radial direction of the substrate at the point of the time, for example, the groove parts (or land parts 2) are subjected to recording or reproducing in one round. The groove parts 1 and the land parts 2 are so formed that the groove parts 1 (or land parts 2) do not overlap on each other in the parts where the groove parts 1 and the land parts 2 are changed over. The depth of the grooves of the groove parts 1 is 75nm corresponding to λ/η (λis the light wavelength of the light beam). |
