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US4730293A Expired / Lapsed US ⏱️ 0.0 years remaining

Dual beam optical data system

Assignee: LaserCard Corp
•
Filing: 1986-09-15
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Granted: 1988-03-08
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Expires: 2006-09-15
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Abstract

Abstract An optical data reading and writing system in which a laser beam records data spots on a medium and a wide light beam is used for simultaneously reading the data spots and prerecorded information. The laser beam records spots of a uniform size which is less than about ten micrometers. The wide beam which may be emitted by an LED illuminates a substantially larger area of the medium than the laser beam. Prerecorded information, if present, may include parallel track lines, the wide beam illuminating adjacent pairs of track lines in addition to the data spots and prerecorded clock spots in data tracks between the track lines. Multiple data paths may be present between track lines, which may then be read simultaneously by a photodetector. The photodetector may have a plurality of detector elements which have apertures such that simultaneously illuminated data spots are distinguished.

Inventors

  • 👤 Gerald A. Pierce
  • 👤 Louis F. Schaefer
  • 👤 Norman A. Peppers
  • 👤 William F. Mullen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 17:48
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/08; G11B7/09; G11B7/002; G11B7/0033

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 110 words
An optical data reading and writing system comprising, a first light source comprising a laser capable of emitting a modulated laser beam, a second light source emitting a second beam, means for directing said laser beam and said wide beam onto an optical data storage medium, said medium having prerecorded information thereon, said laser beam recording data spots of a uniform size, said size less than about ten micrometers, said second beam having a width illuminating a substantially larger area of said medium than said laser beam, and means for reading said prerecorded information and said recorded data spots from said area of said medium illuminated by said second beam.
Claim 2
Dependent Claim 110 words
An optical data reading and writing system comprising, a first light source comprising a laser capable of emitting a modulated laser beam, a second light source emitting a second beam, means for directing said laser beam and said wide beam onto an optical data storage medium, said medium having prerecorded information thereon, said laser beam recording data spots of a uniform size, said size less than about ten micrometers, said second beam having a width illuminating a substantially larger area of said medium than said laser beam, and means for reading said prerecorded information and said recorded data spots from said area of said medium illuminated by said second beam.
Claim 3
Dependent Claim 13 words
The system of claim 1 wherein said second light source is an LED.
Claim 4
Dependent Claim 14 words
The system of claim 1 wherein said second light source is a defocussed laser.
Claim 5
Dependent Claim 30 words
The system of claim 1 wherein said data spots are aligned in parallel data paths, data spots in a plurality of said paths being illuminated simultaneously by said second beam.
Claim 6
Dependent Claim 22 words
The system of claim 4 wherein a plurality of said paths illuminated by said beam are read simultaneously by said reading means.
Claim 7
Dependent Claim 45 words
The system of claim 4 wherein said prerecorded information comprises a plurality of parallel track lines, at least one data path being disposed between each adjacent pair of said track lines, said prerecorded information further comprising a plurality of clock spots in said data paths.
Claim 8
Dependent Claim 17 words
The system of claim 1 wherein said first and second light sources share a common optical axis.
Claim 9
Dependent Claim 32 words
The system of claim 1 wherein said optical data storage medium is a direct-read-after-write medium, said means for reading being in a position following said laser beam for reading recorded data spots.
Claim 10
Dependent Claim 45 words
The system of claim 1 wherein said reading means comprises a photodetector receiving light scattered from said illuminated area of said medium, said photodetector having a plurality of detector elements, some of said elements reading prerecorded information, some other of said elements reading data spots.
Claim 11
Dependent Claim 58 words
The system of claim 9 wherein said prerecorded information comprises a plurality of parallel track lines, at least one data path having laser recorded data spots being disposed between each adjacent pair of said track lines, said plurality of detector elements of said photodetector being divided into pairs of elements for each track line and each data path.
Claim 12
Dependent Claim 31 words
The system of claim 10 further defined by said pair of elements on a track line providing information for servo tracking by a difference between signals from said pair of elements.
Claim 13
Dependent Claim 24 words
The system of claim 10 further defined by said pair of elements on a data path providing a data and clocking signal by summation.
Claim 14
Dependent Claim 120 words
An optical data card reader-writer comprising, means for supporting a card having an optical data storage medium disposed thereon, said medium having prerecorded information in spaced apart tracks, a first light source comprising a laser capable of emitting a modulated laser beam, a second light source emitting a second beam, means for directing said laser beam and said wide beam onto said medium, said laser beam recording data spots of a uniform size less than ten micrometers in data paths within said spaced apart tracks, said second beam illuminating a substantially larger area of said medium than said laser beam, and means for simultaneously reading said prerecorded information and said data spots from said area illuminated by said second beam.
Claim 15
Dependent Claim 120 words
An optical data card reader-writer comprising, means for supporting a card having an optical data storage medium disposed thereon, said medium having prerecorded information in spaced apart tracks, a first light source comprising a laser capable of emitting a modulated laser beam, a second light source emitting a second beam, means for directing said laser beam and said wide beam onto said medium, said laser beam recording data spots of a uniform size less than ten micrometers in data paths within said spaced apart tracks, said second beam illuminating a substantially larger area of said medium than said laser beam, and means for simultaneously reading said prerecorded information and said data spots from said area illuminated by said second beam.
Claim 16
Dependent Claim 14 words
The card reader-writer of claim 13 wherein said second light source is an LED.
Claim 17
Dependent Claim 27 words
The card reader-writer of claim 14 wherein at least some of said prerecorded information is illuminated along with said data paths, said prerecorded information comprising tracking information.
Claim 18
Dependent Claim 15 words
The card reader-writer of claim 13 wherein said second light source is a defocussed laser.
Claim 19
Dependent Claim 20 words
The card reader-writer of claim 13 wherein a plurality of said data paths are illuminated simultaneously by said wide beam.
Claim 20
Dependent Claim 33 words
The card reader-writer of claim 13 wherein said optical data storage medium is a direct-read-after-write medium, said means for reading being in a position following said laser beam for reading recorded data spots.
Claim 21
Dependent Claim 51 words
The card reader-writer of claim 13 wherein said reading means comprises a photodetector positioned to receive light scattered said illuminated area of said card medium, said photodetector having a plurality of detector elements, some of said elements being adapted for reading prerecorded information, some other of said elements reading data spots.
Claim 22
Dependent Claim 55 words
The card reader-writer of claim 19 wherein said prerecorded information comprises a plurality of parallel track lines, at least one data path having laser recorded data spots being disposed between each adjacent pair of track lines, said plurality of detector elements being divided into pairs of elements for each track line and each data path.
Claim 23
Dependent Claim 33 words
The card reader-writer of claim 20 further defined by said pair of detector elements on a track line providing information for servo tracking by a difference between signals from said pair of elements.
Claim 24
Dependent Claim 23 words
The card media-writer of claim 20 further defined by said pair of detector elements on a data path providing a data by summation.

References Cited (Backward Citations)

US4290122A Cited
US4425636A Cited
US4360728A Cited
US4500777A Cited
US4542288A Cited
US4500777B1 Cited
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US4544835B1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-03-08 1991-09-07 1992-03-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-03-08 1995-09-07 1996-03-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-03-08 1999-09-07 2000-03-08 $7700.00 Window Closed / Lapsed

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