Laser mass memory system

The design and implementation of a laser mass memory system of 10¹²bits gross capacity is discussed. The major system design considerations and implementation constraints are described. Data are permanently recorded in the form of track-oriented patterns of vaporized regions on a reflective metallic recording surface. The system is composed of two major elements, the laser recorder unit and the recorder control unit. The optical path configuration of the laser recorder unit is described, together with the use of an intensity-modulated laser beam to thermally vaporize and reflectively read data patterns on a rotating strip of the recording medium. The operation of the recorder control unit, in conjunction with both the permanent recording and nondestructive retrieval processes is discussed, as well as its interface with a host computer. A typical track-oriented data organization is described, and information is provided regarding data capacity, access timing, and data rates of an operational laser mass memory system.