Leslie A Johnson

US Patent:

40756122, Feb 21, 1978

Filed:

Jan 3, 1977

Appl. No.:

5/756223

Inventors:

Leslie Harold Johnson - Minneapolis MN
David Shih-Fang Lo - Burnsville MN
Maynard Carlton Paul - Bloomington MN

Assignee:

Sperry Rand Corporation - New York NY

International Classification:

G11C 1908

US Classification:

365171

Abstract:

The design of a magnetic film strip for defining the data track of a cross-tie wall memory system is disclosed. The design involves the conformation or shaping of the opposing edges of the film strip into repetitive, rounded, asymmetrical serrated edge contours. The serrated edge shape structures the cross-tie of each cross-tie, Bloch-line pair at the narrowest width dimension across the film strip while the Bloch-line is positioned at the widest width dimension across the film strip or at the round, convex, portion of the repetitive serrated edge shape. The asymmetrical, rounded edge contour is substantially in alignment with the natural contour of the magnetization that is oriented around a Bloch-line that is positioned on the cross-tie wall, which cross-tie wall is aligned along and superposed the geometric centerline of the film strip.

US Patent:

41986865, Apr 15, 1980

Filed:

Feb 23, 1979

Appl. No.:

6/020764

Inventors:

George F. Nelson - Coon Rapids MN
Gregory J. Cosimini - St. Paul MN
Leslie H. Johnson - Minneapolis MN
David S. Lo - Burnsville MN
Maynard C. Paul - Bloomington MN
Ernest J. Torok - Minneapolis MN

Assignee:

Sperry Corporation - New York NY

International Classification:

G11C 1908

US Classification:

365 79

Abstract:

A method of and an apparatus for counting is disclosed. The counter includes a generator of cross-tie, Bloch-line pairs and a shift register of N stages or memory cells along which the cross-tie, Bloch-line pairs are propagated or replicated into a detector. The method includes coupling a series of bipolar push-nucleate replicate signals, each one of which produces a cross-tie, Bloch-line pair in the adjacent downstream memory cell along the shift register. When the shift register is filled, a cross-tie will appear in the detector. This provides an output signal indicating that the N memory cells have been filled by the N replicate signals.

US Patent:

42505658, Feb 10, 1981

Filed:

Feb 23, 1979

Appl. No.:

6/020762

Inventors:

Gregory J. Cosimini - St. Paul MN
Leslie H. Johnson - Minneapolis MN
David S. Lo - Burnsville MN
George F. Nelson - Coon Rapids MN
Maynard C. Paul - Bloomington MN

Assignee:

Sperry Corporation - New York NY

International Classification:

G11C 1100

US Classification:

365 87

Abstract:

Disclosed is a cross-tie wall memory system for the generating, propagating and detecting of binary data represented by the presence or absence of cross-tie, Bloch-line pairs along a cross-tie wall in a thin magnetic layer. The system includes a three-level structure comprised of the following superposed layers: a straight-edged current conductive stripline; a serrated-edged thin magnetic layer data track, and a wide-narrow-edged current conductive stripline terminated on one end by a cross-tie, Bloch-line pair generator and on the other end by a cross-tie detector.

US Patent:

42466474, Jan 20, 1981

Filed:

Feb 23, 1979

Appl. No.:

6/020761

Inventors:

Leslie H. Johnson - Minneapolis MN
George F. Nelson - Coon Rapids MN
Vernal M. Benrud - Eagan MN

Assignee:

Sperry Corporation - New York NY

International Classification:

G11C 1102

US Classification:

365 8

Abstract:

A method of and an apparatus for magneto-resistively detecting information in a cross-tie memory system is disclosed. The detector includes a first conductive element, which is the terminating portion of an electrically-conducting wide-narrow edged propagating drive line, and second and third conductive elements that are serially aligned along a magnetic, serrated-edged data track, which three conductive elements form two gaps therebetween. The two gaps are oriented along the data track at respective narrow portions, a first narrow portion which may support a cross-tie but which second narrow portion will not support a cross-tie. A differential sense amplifier is coupled across the two gaps using the second narrow portion as a reference segment to differentially detect the presence vel non of a cross-tie in the first narrow portion.

US Patent:

45698813, Feb 11, 1986

Filed:

Apr 12, 1984

Appl. No.:

6/599647

Inventors:

Robert P. Freese - Lake Elmo MN
Leslie H. Johnson - Hudson WI
Thomas A. Rinehart - St. Paul MN
Richard N. Gardner - Grant Township, Washington County both of MN

Assignee:

Minnesota Mining and Manufacturing Company - St. Paul MN

International Classification:

G11B 900

US Classification:

428213

Abstract:

A multi-layer magneto optical thin film recording medium is disclosed having very high carrier-to-noise ratios (at least 47 decibels) and high rotation angles. A transmission electron microscope photomicrograph (at 200,000 X) of one such medium is shown in FIG. 1. The magneto optic layer is a multi-phase amorphous material having magnetic anisotropy perpendicular to the plane of the thin film produced in a triode vacuum sputtering process at vacuums in the range of 4. times. 10. sup. -3 to 6. times. 10. sup. -4 Torr. Various transparent layers, such as dielectric intermediate and anti-reflective layers and a protective covering layer, are combined with the magneto optic layer and a reflective surface to yield media having enhanced carrier-to-noise ratio and magnetic optic angle of rotation.