04961123 is referenced by 52 patents and cites 4 patents.

A magnetic information storage medium, such as a floppy or rigid magnetic disk having a plurality of indelible grooves inscribed on a surface of the medium to function as optical servo tracks. The grooves can be in the form of a plurality of continuous or noncontinuous concentric circles. The grooves can also be a continuous spiral or a plurality of continuous concentric circles having non-constant widths and/or depths.

Title
Magnetic information media storage with optical servo tracks
Application Number
7/202719
Publication Number
4961123
Application Date
June 3, 1988
Publication Date
October 2, 1990
Inventor
Gregory K Roberts
San Jose
CA, US
Stephen P Williams
San Jose
CA, US
Jimmy D Godwin
San Jose
CA, US
Milton C Kurtz
Saratoga
CA, US
Roger O Williams
Fremont
CA, US
Agent
Thomas E Schatzel
Assignee
Insite Peripherals
CA, US
IPC
G11B 5/012
G11B 21/10
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