Patent · US Expired

Magneto resistive bubble detection device

US3953840A · kind A · utility

6Cited by
4References
9Claims
0Family size

Inventors

Key dates

Filing dateMay 13, 1974
Grant dateApr 27, 1976
Priority date
Expiry dateMay 13, 1994

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R33/09
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A differential detection device is provided for detecting the presence of magnetic bubbles in a data stream circulating on a magnetic wafer. The device utilizes an array of columns of permalloy elements to enlarge the magnetic bubbles being detected. A change in resistance of each of a pair of adjacent permalloy columns as a bubble traverses the detector is sensed and differentially detected to signify the presence of the bubble. In one embodiment of the invention, a second detector is used in conjunction with the first detector to provide operation in a mode in which bubbles in alternate positions in the data stream are directed into alternate channels including the first and second detectors respectively. After detection, the bubbles are redirected into a single data stream, while the output signals from the two detectors are merged to produce a data output signal reproducing the original data stream.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.