04414554 is referenced by 41 patents and cites 9 patents.

Apparatus for producing in a magnetic image-storage medium a high-resolution, smooth-edge-defining magnetic image. Such is accomplished through the cooperative action of two, opposite-polarity, concentric magnetic poles which function to create, on a face in such a medium, a somewhat doughnut-shaped defined magnetized zone, which zone is characterized by multi-directionally oriented magnetic vectors distributed generally with spherical geometry. The magnetic poles are created by exciting electrically magnetic-flux-inducing spiral coils which are spaced from the magnetic poles.

Title
Magnetic imaging apparatus
Application Number
6/170788
Publication Number
4414554
Application Date
July 21, 1980
Publication Date
November 8, 1983
Inventor
Gilbert D Springer
Sunnyvale
CA, US
Agent
Kolisch Hartwell & Dickinson
Assignee
Ferix Corporation
CA, US
IPC
G01D 15/12
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