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US5563731A Expired / Lapsed US ⏱️ 0.0 years remaining

Monitor control signal receiving apparatus for optical fiber amplifier

Assignee: NEC Corp
•
Filing: 1995-02-22
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Granted: 1996-10-08
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Expires: 2015-02-22
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Abstract

Abstract A monitor control signal receiving apparatus for an optical fiber amplifier includes a laser diode, an optical coupler, a rare-earth-element-doped optical fiber, a pin photodiode, a controller, and a monitor signal extractor. The laser diode generates pump light. The optical coupler optically wavelength-multiplexes an input optical signal and the pump light from the laser diode. The rare-earth-element-doped optical fiber receives the optical signal and pump light from the optical coupler. The pin photodiode converts part of an optically amplified optical signal from the rare-earth-element-doped optical fiber into an electrical signal. The controller compares the electrical signal from the photoelectric converter with a reference voltage to control the laser diode such that an output level of the optical signal from the optical fiber is kept constant. The monitor signal extractor extracts a monitor control signal from an output from the controller.

Inventors

  • 👤 Koji Asahi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 03:06
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/05; H01S3/06; H01S3/063; H01S3/067; H01S3/06754; H01S3/10; H01S3/13; H01S3/1301; H01S3/13013; H01S5/00; H01S5/06; H01S5/068; H01S5/0683; H01S5/06832

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 135 words
A monitor control signal receiving apparatus for an optical fiber amplifier, comprising: pump light generating means for generating pump light; optical coupler means for optically wavelength-multiplexing an input optical signal and the pump light from said pump light generating means; a rare-earth-element-doped optical fiber for receiving the optical signal and pump light from said optical coupler means; photoelectric converting means for converting part of an optically amplified optical signal from said rare-earth-element-doped optical fiber into an electrical signal; control means for comparing the electrical signal from said photoelectric converting means with a reference voltage to control said pump light generating means such that an output level of the optical signal from said optical fiber is kept constant; and monitor signal extracting means for extracting a monitor control signal from an output from said control means.
Claim 2
Dependent Claim 135 words
A monitor control signal receiving apparatus for an optical fiber amplifier, comprising: pump light generating means for generating pump light; optical coupler means for optically wavelength-multiplexing an input optical signal and the pump light from said pump light generating means; a rare-earth-element-doped optical fiber for receiving the optical signal and pump light from said optical coupler means; photoelectric converting means for converting part of an optically amplified optical signal from said rare-earth-element-doped optical fiber into an electrical signal; control means for comparing the electrical signal from said photoelectric converting means with a reference voltage to control said pump light generating means such that an output level of the optical signal from said optical fiber is kept constant; and monitor signal extracting means for extracting a monitor control signal from an output from said control means.
Claim 3
Dependent Claim 65 words
An apparatus according to claim 1, wherein said control means comprises current/voltage converting means for converting a current signal representing an electrical signal from said photoelectric converting means into a voltage signal and comparing means for comparing the voltage signal from said current/voltage converting means with said reference voltage, and said pump light generating means is controlled based on an output from said comparing means.
Claim 4
Dependent Claim 41 words
An apparatus according to claim 1, further comprising filter means for removing a noise component included in an output from said control means, and driving means for driving said pump light generating means based on an output from said filter means.
Claim 5
Dependent Claim 16 words
An apparatus according to claim 1, wherein said rare-earth-element-doped optical fiber comprises an Er-doped optical fiber.
Claim 6
Dependent Claim 16 words
An apparatus according to claim 1, wherein said pump light generating means comprises a laser diode.
Claim 7
Dependent Claim 15 words
An apparatus according to claim 1, wherein said photoelectric converting means comprises a pin photodiode.

References Cited (Backward Citations)

US4995100A Cited
JPH02119328A Cited
US5054876A Cited
JPH0387727A Cited
US5138621A Cited
US5355250A Cited
JPH06338874A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-10-08 2000-04-08 2000-10-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-10-08 2004-04-08 2004-10-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-10-08 2008-04-08 2008-10-08 $7700.00 Window Closed / Lapsed

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