US5351324A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fiber optic security seal including plural Bragg gratings
Assignee: Los Alamos National Security LLC
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Filing: 1993-09-10
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Granted: 1994-09-27
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Expires: 2013-09-10
Abstract
Abstract An optical security system enables the integrity of a container seal to be remotely interrogated. A plurality of Bragg gratings is written holographically into the core of at least one optical fiber placed about the container seal, where each Bragg grating has a predetermined location and a known frequency for reflecting incident light. A time domain reflectometer is provided with a variable frequency light output that corresponds to the reflecting frequencies of the Bragg gratings to output a signal that is functionally related to the location and reflecting frequency of each of the Bragg gratings.
Inventors
- 👤 Peter R. Forman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:32
CPC Classifications
G; G09; G09F; G09F3/00; G09F3/02; G09F3/03; G09F3/0376
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
121 words
A fiber optic security seal system, comprising: an optical fiber having a plurality of reflective Bragg gratings induced in the fiber, where each grating has a unique location and wavelength for reflecting incident light; a light source means for providing input light to said fiber at all of said wavelengths for reflecting light from said gratings; a time domain reflectometer for receiving reflected light from said gratings and outputting a signal functionally related to said unique location and wavelength for reflecting incident light for each said grating; and a coating over an end of said optical fiber receiving said incident light said coating having a crystal pattern that produces a unique holographic image to verify an identity of said optical fiber.
Claim 2
Dependent Claim
121 words
A fiber optic security seal system, comprising: an optical fiber having a plurality of reflective Bragg gratings induced in the fiber, where each grating has a unique location and wavelength for reflecting incident light; a light source means for providing input light to said fiber at all of said wavelengths for reflecting light from said gratings; a time domain reflectometer for receiving reflected light from said gratings and outputting a signal functionally related to said unique location and wavelength for reflecting incident light for each said grating; and a coating over an end of said optical fiber receiving said incident light said coating having a crystal pattern that produces a unique holographic image to verify an identity of said optical fiber.
Claim 3
Dependent Claim
20 words
A fiber optic security seal system according to claim 1, wherein said optical fiber has a core doped with germanium.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-09-26 | 1998-03-28 | 1998-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-26 | 2002-03-28 | 2002-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-09-26 | 2006-03-28 | 2006-09-27 | $7700.00 | Window Closed / Lapsed |