Optical mass data memory
Device for the optical read-out of a diffractive track belonging to a data carrier in the form of a disc or tape
Head positioning servo system for disk drives
Optical mass memory Patent #: 3996570
ApplicationNo. 686254 filed on 05/13/1976
US Classes:369/30.01, Selective addressing of storage medium (e.g., programmed access)360/77.08, Distinct servo sector365/25, Velocity365/215, Optical369/44.26, Servo system operation related to disc structure information format369/44.38, Recording369/111, Spiral or helical track369/275.3, Track data format/layout369/278Groove acts as control system signal
ExaminersPrimary: Konick, Bernard
Assistant: McElheny, Donald Jr.
Attorney, Agent or Firm
International ClassesG11B 007/00
Foreign Application Priority Data1975-05-22 DT
AbstractA storage disk comprising at least one data track which is composed of spiral-shaped turns or concentrical turns, the data being arranged in the form of data blocks on the turns so that between the data blocks alternately a guide segment or a blank segment is present. The lengths of the unit, measured in angular degrees, consisting of data block and guide segment and the unit consisting of data block and blank segment are substantially the same and are chosen so that the same number of units is accommodated in each turn. The spirals are sub-divided into sectors which contain only data blocks or only guide segments or blank segments. In each sector containing guide segments the radial distance between these segments is substantially twice the distance between the data blocks in each sector containing data blocks. The invention also relates to a device for writing and/or reading data of a rotating disk as described, comprising a light deflection system which notably includes a slow light deflector and a fast light deflector, the latter deflector scanning the guide segments.