Patent EP0517491A2 successfully refreshed from Google Patents.
EP0517491A2
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Multiple data surface optical data storage system and method
Assignee: International Business Machines Corp
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Filing: 1992-06-02
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Granted: —
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Expires: 2012-06-02
Abstract
Abstract Described is an optical data storage system which comprises a multiple data surface medium (12) and optical head. The medium comprises a plurality of substrates separated by a light transmissive medium. Data surfaces are located on the substrate surfaces which lie adjacent a light transmissive medium. The data surfaces are substantially light transmissive. The optical head includes an aberration compensator (602) to allow the head to focus accurately onto the different data surfaces. <IMAGE>
Inventors
- 👤 Hal Jervis Rosen
- 👤 Kurt Allan Rubin
- 👤 Glenn Tavernia Sincerbox
- 👤 Timothy Carl Strand
- 👤 James Matthew Zavislan
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 19:12
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/12; G11B7/135; G11B7/1381; G11B7/24; G11B7/2403; G11B7/24035; G11B7/24038; G02; G02B; G02B27/00; G02B27/0025; G02B5/00; G11B7/004; G11B7/08; G11B7/09; G11B7/0908; G11B7/1359; G11B7/1365; G11B7/1369; G11B7/1372; G11B7/1378; G11B7/1392; G11B7/13925; G11B2007/0003; G11B2007/0009; G11B2007/0013
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
97 words
An optical data storage system comprising: a light source (200); an optical medium having a plurality of data surfaces (90, 92, 94); focusing means (21)) for focusing a light beam from the light source to one of the data surfaces; an adjustable aberration compensator (212; 602) for adjusting the spherical aberration of the light beam in order to compensate for spherical aberration encountered due to the different depths of data surfaces; an optical reception means (210, 208, 205, 224, 232, 234) for receiving a reflected beam from the optical medium and providing a data signal responsive thereto.
Claim 2
Dependent Claim
18 words
A system as claimed in claim 1, wherein the aberration compensator comprises a variable thickness light transmissive element.
Claim 3
Dependent Claim
20 words
A system as claimed in claim 2, wherein the aberration compensator comprises a movable transparent block (400) having stepped thicknesses.
Claim 4
Dependent Claim
20 words
A system as claimed in claim 2, wherein the aberration compensator comprises a rotatable transparent block (450) having stepped thicknesses.
Claim 5
Dependent Claim
28 words
A system as claimed in claim 2, wherein the aberration compensator comprises a pair of complementary transparent triangular blocks (432, 434) which are movable relative to one another.
Claim 6
Dependent Claim
21 words
A system as claimed in claim 1, wherein the aberration compensator comprise a transmissive element (582) having a spherical aberration surface.
Claim 7
Dependent Claim
26 words
A system as claimed in claim 1, wherein the aberration compensator comprises a convex (572) and concave (574) lens which are movable relative to one another.
Claim 8
Dependent Claim
24 words
A system as claimed in claim 1, wherein the aberration compensator comprises a rotatable hologram (610) having a plurality of spherical aberration compensation recordings.
Claim 9
Dependent Claim
19 words
A system as claimed in claim 1, wherein the aberration compensator comprises a mirror having an aberration compensation surface.
Claim 10
Dependent Claim
28 words
A system as claimed in claim 9, wherein the aberration compensator comprises a beamsplitter (702), a quarter waveplate and a plurality of mirrors (710) with aberration correction surfaces.
Claim 11
Dependent Claim
25 words
A system as claimed in claim 9, wherein the aberration compensator comprises a beamsplitter (722), a quarter waveplate (724) and a piezo-electric surface mirror (726).
Claim 12
Independent Claim
64 words
A method for operating an optical data storage system comprising the steps of: generating a beam of light; focusing the beam of light; changing the spherical aberration of the beam of light; directing the beam of light to an optical medium having a plurality of data surfaces; and receiving a reflected beam of light from the medium and generating a data signal responsive thereto.
References Cited (Backward Citations)
No citation records indexed.
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