EP0089734A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Disk-shaped record carrier
Assignee: Control Data Corp
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Filing: 1983-01-24
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Granted: —
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Expires: 2003-01-24
Abstract
Abstract A disk-shaped record carrier for an optical recording system has concentric information tracks (12). A plurality of preformatted clock locations (14,16) prewritten into each of the concentric information tracks at equi-spaced intervals, information being written using a selected one or none of a predetermined plurality of possible writing locations (18,20, 22) between each pair of clock locations, the particular location between clock locations being representative of the data.
Inventors
- 👤 William Joseph Stanis
- 👤 Dorrel Robert Silvy
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 19:21
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/2407; G11B7/24085; G11B7/007; G11B7/013; G11B7/08; G11B7/085
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
76 words
A disk-shaped record carrier for an optical recording system characterised by having a plurality of concentric information tracks (12) having a plurality of preformatted clock locations (14, 16) prewritten into each of said concentric information tracks at equi-spaced intervals, information being written using a selected one or none of a predetermined plurality of possible writing locations (18, 20, 22) between each pair of clock locations, the particular location between clock locations being representative of the data.
Claim 2
Dependent Claim
76 words
A disk-shaped record carrier for an optical recording system characterised by having a plurality of concentric information tracks (12) having a plurality of preformatted clock locations (14, 16) prewritten into each of said concentric information tracks at equi-spaced intervals, information being written using a selected one or none of a predetermined plurality of possible writing locations (18, 20, 22) between each pair of clock locations, the particular location between clock locations being representative of the data.
Claim 3
Dependent Claim
83 words
A record carrier as claimed in claim 1 characterised in that the clock locations on adjacent concentric information tracks are presented in a predetermined pattern of locations off the centre of the track and within a guard band separating tracks so that a reading mechanism of the optical recording system traversing tracks radially while the record carrier is rotating will read a signal indicative of track crossing and track counting information as a result of the predetermined pattern of off centre clock locations.
Claim 4
Dependent Claim
45 words
A record carrier as claimed in claim 1 or 2 characterised in that one of four predetermined values may be indicated between clock locations by the absence of a written signal or by the presence of a written signal at one of three writing locations.
Claim 5
Dependent Claim
26 words
A record carrier as claimed in any preceding claim characterised in that the absence of a written location between clock locations represents a zero data value.
References Cited (Backward Citations)
No citation records indexed.
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