| 摘要 |
PURPOSE:To attain quick search, by shifting a pickup by a distance based on a distance data between the radius of the present position and that of the objective position of the pickup, in the reproduction of a disc on which a digital data is recorded. CONSTITUTION:The radius of a disc 140 of the present and the objective positions is calculated from the absolute address of the positions of a pickup 142 and the distance to shift the pickup is determined by obtaining the difference of the both. Then, the number of pulses of a position detecting signal generating one pulse every time the pickup is shifted and the spot crosses one track is counted and when the shift distance of the pickup is equal to the said distance data, the shift is stopped. Further, the absolute address is coverted into the radius data with a rough conversion table stored in ROMs 181, 183 and the pickup is shifted by it and when the pickup reaches a prescribed range or smaller, the absolute address is converted into the radius data with a minute conversion table stored in ROMs 182, 184 and the pickup is shifted by it. |
