| 摘要 |
PURPOSE:To enable to retrieve in high speed with a simple constitution and high reliability, by controlling the relative movement between the conversion means for playback and recording medium through the count of track crossing signal and external scale signal with switching. CONSTITUTION:Based on the count of amount of position movement to the desired track by the information processing controller 1, the amount of shift according to the external scale of the N-th power (where; N is a positive real number greater than 1) of the track pitch 2 and the track crossing number corresponding to the fraction of external scale are set to the 1st and 2nd registers 2, 3. Further, the switching of the switches 4, 5 and 12 via the device 1 is controlled to separately switch the count of the external scale and track crossing number, and the relative movement between th playback conversion means and recording medium can be controlled with the coincident output from the 1st and 2nd comparison circuits 10, 11 via the AND gate 12. Thus, high speed retrieval with high reliability can be made by using the constitution of a simple external scale, except slow speed for the vicinity of start and end of the movement. |
