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US5199023A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical information recording medium with a separating part between information tracks

Assignee: Canon Inc
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Filing: 1989-12-27
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Granted: 1993-03-30
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Expires: 2009-12-27
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Abstract

Abstract An optical information recording medium includes a recording surface formed by a recording layer provided on a substrate, the recording surface being provided with parallel information tracks each divided into plural blocks, each of which is formed by a data area for information recording and a servo area for forming prepits for tracking signal detection, wherein the data area has a separating part the height of which is different from that of the information track and which is provided between information tracks adjacent to each other, and the difference in height is equal to or larger than the thickness of the recording layer, and wherein the servo area is not provided within the separating part.

Inventors

  • 👤 Masakuni Yamamoto
  • 👤 Shigeto Kanda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 21:43
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/08; G11B7/09; G11B7/0938; G11B7/24; G11B7/2407; G11B7/24073; G11B7/24079; G11B7/007; G11B7/00745

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 141 words
An optical information recording medium comprising: a recording surface formed by a recording layer provided on a substrate, said recording surface comprising information tracks each divided into a plurality of blocks, each of which includes a data area for information recording and a servo area comprising prepits for tracking signal detection; wherein said data area has a separating part the height of which is different from that of the information tracks and which is provided between information tracks adjacent to each other, and said servo area is not provided with said separating part; and wherein the recording layer of the information tracks and the recording layer of the separating part are continuously formed, free from discontinuity, and the difference in height between the information tracks and the separating part is greater than or equal to the thickness of said recording layer.
Claim 2
Dependent Claim 141 words
An optical information recording medium comprising: a recording surface formed by a recording layer provided on a substrate, said recording surface comprising information tracks each divided into a plurality of blocks, each of which includes a data area for information recording and a servo area comprising prepits for tracking signal detection; wherein said data area has a separating part the height of which is different from that of the information tracks and which is provided between information tracks adjacent to each other, and said servo area is not provided with said separating part; and wherein the recording layer of the information tracks and the recording layer of the separating part are continuously formed, free from discontinuity, and the difference in height between the information tracks and the separating part is greater than or equal to the thickness of said recording layer.
Claim 3
Dependent Claim 31 words
An optical information recording medium according to claim 1, wherein the surface of said servo area, other than the prepits, as well as said separating area are in the same plane.
Claim 4
Dependent Claim 38 words
An optical information recording medium according to claim 1, wherein said prepits comprise two wobble pits positioned on mutually opposite sides in the direction of the width of an information track with respect to the center line thereof.
Claim 5
Dependent Claim 22 words
An optical information recording medium according to claim 3, wherein said prepits further comprise a clock pit for detecting a clock signal.
Claim 6
Dependent Claim 166 words
An optical information recording medium comprising: a recording surface formed by a recording layer provided on a substrate, said recording surface comprising information tracks each divided into a plurality of blocks, each of which includes a data area for information recording and a servo area comprising prepits for tracking signal detection; wherein said data area has a separating part the height of which is different from that of the information tracks and which is provided between information tracks adjacent to each other, and said servo area is not provided with said separating part; and wherein the difference in height between the information tracks and the separating part is greater than or equal to the thickness of said recording layer, and the depth of said prepits and the difference in height between the information tracks and the separating part are equal to λ/4n, wherein λ is the wavelength of a light beam for reading information from said medium and n is the refractive index of said substrate.
Claim 7
Dependent Claim 166 words
An optical information recording medium comprising: a recording surface formed by a recording layer provided on a substrate, said recording surface comprising information tracks each divided into a plurality of blocks, each of which includes a data area for information recording and a servo area comprising prepits for tracking signal detection; wherein said data area has a separating part the height of which is different from that of the information tracks and which is provided between information tracks adjacent to each other, and said servo area is not provided with said separating part; and wherein the difference in height between the information tracks and the separating part is greater than or equal to the thickness of said recording layer, and the depth of said prepits and the difference in height between the information tracks and the separating part are equal to λ/4n, wherein λ is the wavelength of a light beam for reading information from said medium and n is the refractive index of said substrate.
Claim 8
Dependent Claim 31 words
An optical information recording medium according to claim 5, wherein the surface of said servo area, other than the prepits, as well as said separating area are in the same plane.
Claim 9
Dependent Claim 35 words
An optical information recording medium according to claim 5, wherein the surface of said servo area, other than the prepits, as well as the information tracks of said data area are in the same plane.
Claim 10
Dependent Claim 38 words
An optical information recording medium according to claim 5, wherein said prepits comprise two wobble pits positioned on mutually opposite sides in the direction of the width of an information track with respect to the center line thereof.
Claim 11
Dependent Claim 22 words
An optical information recording medium according to claim 8, wherein said prepits further comprise a clock pit for detecting a clock signal.
Claim 12
Dependent Claim 17 words
An optical information recording medium according to claim 5, wherein said recording layer comprises a magnetic film.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-03-29 1996-09-28 1997-03-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-03-29 2000-09-28 2001-03-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-03-29 2004-09-28 2005-03-30 $7700.00 Window Closed / Lapsed

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