Contiguous element field access bubble lattice file

Abstract

A bubble domain storage system is described which has the best features of contiguous element bubble propagation systems and bubble lattice file systems. An array of magnetic bubble domains, such as a lattice, is moved along contiguous propagation patterns in response to the reorientation of a magnetic field in the plane of the bubble domain film. Adjacent rows of bubble domains in the array move in opposite directions to provide individual storage loops within the array. Information accessing can be achieved by the use of input/output registers similar to those used in other contiguous disk bubble domain storage systems. For example, the storage system can be a conventional major/minor loop organization using contiguous element propagation patterns for the storage registers and for the input/output registers. Every bit position in the storage registers is populated by a bubble domain where the average distance between adjacent bubble domains is less than that in a system where bubbles are isolated from one another. For example, the storage registers can be arranged so that the separation between adjacent bubble domains in the storage registers is 2-3 bubble diameters. The bubbles are coded in terms of the magnetic properties of individual bubble domains, or a double layer structure can be used in which an array of bubble domains is in one layer and information bubble domains are in the other layer, coded in accordance with presence/absence. Viewed another way, the invention is a bubble storage system using contiguous propagation elements which is fully populated by interacting bubble domains.