06574174 is referenced by 44 patents and cites 1 patents.

An optical information storage system using optical storage media including multiple data layers or stacks wherein each of the multiple data stacks has a storage density comparable to a conventional single layer optical disk. The optical data storage system comprises an optical medium having a single dedicated servo layer and multiple data stacks which each contain an embedded servo format, a servo laser beam positioned to maintain a first focus point on the dedicated servo reference layer, a read-write laser beam positioned to maintain a second focus point on one of the data stacks, a first, dedicated servo system which provides focus and tracking error correction according to error signals generated from the dedicated servo layer, and a second, embedded servo system which provides focus and tracking error correction according to error signals generated from the data stacks. The dedicated servo layer, in different embodiments of the invention, may be positioned either below or above the data stacks in the optical medium, or interposed between data stacks. The data stacks may comprise discrete physical data layers or “virtual” data layers defined by a format hologram. The servo and read-write lasers may differ in wavelength and/or polarization.

Title
Optical data storage system with multiple layer media
Application Number
9/549075
Publication Number
6574174 (B1)
Application Date
April 15, 2000
Publication Date
June 3, 2003
Inventor
LeRoy A Volz
San Jose
CA, US
Sergei Sochava
Sunnyvale
CA, US
Shunichi Nishimura
Tokyo
US
Matthew Lipson
Sunnyvale
CA, US
Thomas A Kridl
Los Altos
CA, US
Sanjoy Ghose
Scotts Valley
CA, US
Herman A Ferrier
Scotts Valley
CA, US
Andrew J Daiber
Palo Alto
CA, US
Michael V Morelli
San Jose
CA, US
Mark E McDonald
Milpitas
CA, US
Tokyuki Honda
Mountain View
CA, US
Lambrerrtus Hesselink
Atherton
CA, US
James R Amble
Redwood City
CA, US
Agent
Sierra Patent Group
US
Assignee
Siros Technologies
CA, US
IPC
G11B 7/00
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