Patent US5861980A successfully refreshed from Google Patents.
US5861980A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical spectrum analyzer and method for controlling output of optical amplifier
Assignee: NEC Corp
•
Filing: 1996-09-06
•
Granted: 1999-01-19
•
Expires: 2016-09-06
Abstract
Abstract Disclosed is an optical spectrum analyzer which has: a pulse oscillator for generating a pulse; an optical switch for switching a signal light in response to the pulse; an optical circulator which has at least three input-output ports and in which the output of the optical switch is connected to a first port of the optical circulator; a plurality of fiber gratings which are in series connected to a second port of the optical circulator to which a signal light entered into the first port is output, the fiber gratings having different Bragg wavelengths, respectively; and an optical detector which is connected to a third port of the optical circulator to which a reflected light from the fiber gratings is output.
Inventors
- 👤 Takashi Ono
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 21:16
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/29; H04B10/291; H04B10/293; H04B10/294; H04B10/296; H01; H01S; H01S3/00; H01S3/05; H01S3/06; H01S3/063; H01S3/067; H01S3/06754; H01S3/10; H01S3/13; H01S3/1301; H01S3/13013; H04B10/07; H04B10/075; H04B10/077; H04B10/0777; H01S3/005; H01S3/0078; H01S3/1305; H04B2210/00; H04B2210/07; H04B2210/074; H04B2210/078
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
118 words
An optical spectrum analyzer, comprising: a pulse oscillator for generating a pulse; an optical switch for switching a signal light in response to said pulse; an optical circulator which has at least three input-output ports and in which the output of said optical switch is connected to a first port of said optical circulator; a plurality of fiber gratings which are in series connected to a second port of said optical circulator to which a signal light entered into said first port is output, said fiber gratings having different Bragg wavelengths, respectively; and an optical detector which is connected to a third port of said optical circulator to which a reflected light from said fiber gratings is output.
Claim 2
Dependent Claim
118 words
An optical spectrum analyzer, comprising: a pulse oscillator for generating a pulse; an optical switch for switching a signal light in response to said pulse; an optical circulator which has at least three input-output ports and in which the output of said optical switch is connected to a first port of said optical circulator; a plurality of fiber gratings which are in series connected to a second port of said optical circulator to which a signal light entered into said first port is output, said fiber gratings having different Bragg wavelengths, respectively; and an optical detector which is connected to a third port of said optical circulator to which a reflected light from said fiber gratings is output.
Claim 3
Dependent Claim
44 words
An optical spectrum analyzer, according to claim 1, further comprising: a low-pass filter to which the output of said optical detector is input; and a counter which counts the number of output pulses from said low-pass filter over a period of said pulse oscillator.
Claim 4
Dependent Claim
50 words
An optical spectrum analyzer, according to claim 1, further comprising: a low-pass filter to which the output of said optical detector is input; an A/D converter which converts an analog signal output from said low-pass filter into a digital signal; and CPU which input the output from said A/D converter.
Claim 5
Dependent Claim
63 words
An optical spectrum analyzer, according to claim 1, wherein: said fiber gratings having equal reflection bands and located at equal intervals, wherein a Bragg wavelength of the number n (n is a natural number) fiber grating is λ0+(n-1)Δλ wherein λ0 is a wavelength shorter than a wavelength band including a WDM signal light to be used and Δλ is a predetermined wavelength step.
Claim 6
Dependent Claim
113 words
An optical spectrum analyzer, comprising: a pulse oscillator for generating a pulse; an optical switch for switching a signal light in response to said pulse, said optical switch having at least two input ports and one output port; a plurality of fiber gratings which are in series connected to output port to which a signal light entered into a first port of said optical switch is outout when said optical switch turns ON, said fiber gratings having different Bragg wavelengths, respectively; and an optical detector which is connected to a second input port of said optical switch to which a reflected light from fiber gratings is output when said optical switch turns OFF.
Claim 7
Dependent Claim
113 words
An optical spectrum analyzer, comprising: a pulse oscillator for generating a pulse; an optical switch for switching a signal light in response to said pulse, said optical switch having at least two input ports and one output port; a plurality of fiber gratings which are in series connected to output port to which a signal light entered into a first port of said optical switch is outout when said optical switch turns ON, said fiber gratings having different Bragg wavelengths, respectively; and an optical detector which is connected to a second input port of said optical switch to which a reflected light from fiber gratings is output when said optical switch turns OFF.
Claim 8
Independent Claim
72 words
A method for controlling the gain, output power and optical band property of an optical amplifier used in a wavelength division multiplexing system, comprising the steps of: detecting the number of channels of signal lights output from said optical amplifier by means for analyzing an optical spectrum; and controlling the output power of a pumping laser such that it falls under a predetermined power value in response to said number of wavelengths.
Claim 9
Independent Claim
72 words
A method for controlling the gain, output power and optical band property of an optical amplifier used in a wavelength division multiplexing system, comprising the steps of: detecting the number of channels of signal lights output from said optical amplifier by means for analyzing an optical spectrum; and controlling the output power of a pumping laser such that it falls under a predetermined power value in response to said number of wavelengths.
References Cited (Backward Citations)
US5268786A
Cited
JPH0621897A
Cited
US5557442A
Cited
US5463487A
Cited
US5570221A
Cited
US5636054A
Cited
US5532864A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-01-18 | 2002-07-20 | 2003-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-01-18 | 2006-07-20 | 2007-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-01-18 | 2010-07-20 | 2011-01-19 | $7700.00 | Window Closed / Lapsed |