Patent US2344490A successfully refreshed from Google Patents.
Patent US4673291A successfully refreshed from Google Patents.
US4673291A
Expired / Lapsed
US
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Method of and device for measuring the attenuation in optical waveguides
Assignee: US Philips Corp
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Filing: 1985-06-21
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Granted: 1987-06-16
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Expires: 2005-06-21
Abstract
Abstract The attenuation of an optical waveguide is measured by comparing the light power input into the waveguide with the light power output from the waveguide. The input power is encoded on the light signal by pulse frequency modulation. The output power is measured by a light receiver.
Inventors
- 👤 Siegfried Heckmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:01
CPC Classifications
G; G01; G01M; G01M11/00; G01M11/30; G01M11/33; G01M11/332; G01M11/333; G01M11/335
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
153 words
A method of measuring the attenuation of an optical waveguide, said method comprising the steps of: injecting a light signal into a first end of an optical waveguide, said light signal passing through the waveguide and out a second end of the waveguide; measuring the average input power of the light signal in the vicinity of the first end of the waveguide; modulating the light signal, before it enters the first end of the waveguide, as a function of the measured average input power of the light signal, said modulated light signal having a substantially constant average input power; measuring the average output power of the light signal at the second end of the waveguide; demodulating the light signal at the second end of the waveguide to determine the average input power; and comparing the demodulated measured average input power with the measured average output power and calculating the attenuation of the waveguide.
Claim 2
Independent Claim
153 words
A method of measuring the attenuation of an optical waveguide, said method comprising the steps of: injecting a light signal into a first end of an optical waveguide, said light signal passing through the waveguide and out a second end of the waveguide; measuring the average input power of the light signal in the vicinity of the first end of the waveguide; modulating the light signal, before it enters the first end of the waveguide, as a function of the measured average input power of the light signal, said modulated light signal having a substantially constant average input power; measuring the average output power of the light signal at the second end of the waveguide; demodulating the light signal at the second end of the waveguide to determine the average input power; and comparing the demodulated measured average input power with the measured average output power and calculating the attenuation of the waveguide.
Claim 3
Dependent Claim
22 words
A method as claimed in claim 1, characterized in that the light signal is modulated before its average input power is measured.
Claim 4
Dependent Claim
47 words
A method as claimed in claim 2, characterized in that: the light signal comprises light pulses having lengths; and the step of modulating the light signal comprises changing the lengths of the light pulses as a function of the measured average input power of the light signal.
Claim 5
Dependent Claim
25 words
A method as claimed in claim 3, further comprising the step of displaying the measured average output power and the demodulated measured average input power.
Claim 6
Dependent Claim
19 words
A method as claimed in claim 1, further comprising the step of displaying the calculated attenuation of the waveguide.
Claim 7
Independent Claim
163 words
A device for measuring the attenuation of an optical waveguide, said device comprising: means for injecting a light signal into a first end of an optical waveguide, said light signal passing through the waveguide and out a second end of the waveguide; means for measuring the average input power of the light signal in the vicinity of the first end of the waveguide; means for modulating the light signal, before it enters the first end of the waveguide, as a function of the measured average input power of the light signal, said modulated light signal having a substantially constant average input power; means for measuring the average output power of the light signal at the second end of the waveguide; means for demodulating the light signal at the second end of the waveguide to determine the average input power; and means for comparing the demodulated measured average input power with the measured average output pwer and for calculating the attenuation of the waveguide.
Claim 8
Independent Claim
163 words
A device for measuring the attenuation of an optical waveguide, said device comprising: means for injecting a light signal into a first end of an optical waveguide, said light signal passing through the waveguide and out a second end of the waveguide; means for measuring the average input power of the light signal in the vicinity of the first end of the waveguide; means for modulating the light signal, before it enters the first end of the waveguide, as a function of the measured average input power of the light signal, said modulated light signal having a substantially constant average input power; means for measuring the average output power of the light signal at the second end of the waveguide; means for demodulating the light signal at the second end of the waveguide to determine the average input power; and means for comparing the demodulated measured average input power with the measured average output pwer and for calculating the attenuation of the waveguide.
Claim 9
Dependent Claim
22 words
A device as claimed in claim 6, characterized in that the light signal is modulated before its average input power is measured.
Claim 10
Dependent Claim
49 words
A device as claimed in claim 7, characterized in that: the light signal comprises light pulses having lengths; and the means for modulating the light signal comprises means for changing the lengths of the light pulses as a function of the measured average input power of the light signal.
Claim 11
Dependent Claim
18 words
A device as claimed in claim 8, further comprising means for displaying the demodulated measured average input power.
Claim 12
Dependent Claim
18 words
A device as claimed in claim 8, further comprising means for displaying the calculated attenuation of the waveguide.
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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) | 1990-06-15 | 1990-12-15 | 1991-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-15 | 1994-12-15 | 1995-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-15 | 1998-12-15 | 1999-06-16 | $7700.00 | Window Closed / Lapsed |