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US5414554A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical semiconductor amplifier

Assignee: NEC Corp
•
Filing: 1993-10-13
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Granted: 1995-05-09
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Expires: 2013-10-13
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Abstract

Abstract An optical semiconductor amplifier of the present invention comprises an input optical waveguide medium for feeding input light. A first optical branching circuit which is included a first optical coupler splits the input light into two. An optical semiconductor amplifier amplifies one of two light split by the first optical branching circuit. A first photodetector receives the other of the two light and generates a corresponding first electric signal. A second optical branching circuit which is included a second optical coupler splits the light amplified from the optical semiconductor amplifier into two. A second photodetector receives one of two light split by the second optical branching circuit, and generates a corresponding second electric signal. An output optical waveguide receives the other of the two light split by the second optical branching circuit. A feedback control circuit controls an injection current to the optical semiconductor amplifier in response to the first and second electric signals.

Inventors

  • 👤 Tsutomu Aoyama

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 16:28
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/50; G; G02; G02B; G02B6/00; G02B6/10; G02B6/12; G02B6/122; G02B6/125; G02B6/24; G02B6/42; G02B6/4201; G02B6/4204; G02B6/4206; H01S5/02; H01S5/022; H01S5/0225; H01S5/02251; H01S5/023; H01S5/02325; H01S5/06; H01S5/068; H01S5/0683

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 153 words
An optical semiconductor amplifier comprising: an input optical waveguide medium for feeding input light; first optical coupling means including first optical branching means for splitting said input light into a first beam and a second beam; optical semiconductor amplifier means for amplifying said first beam; first photodetector means for receiving said second beam and generating a corresponding first electric signal; second optical coupling means including second optical branching means for splitting a third beam of light into a fourth beam and a fifth beam, wherein said third beam is an amplification of said first beam by said optical semiconductor amplifier element; second photodetector means for receiving said fifth beam and generating a corresponding second electric signal; an output waveguide medium for receiving said fourth beam; and feedback control circuit means for controlling an injection current to said optical semiconductor amplifier means in response to said first electric signal and said second electric signal.
Claim 2
Dependent Claim 153 words
An optical semiconductor amplifier comprising: an input optical waveguide medium for feeding input light; first optical coupling means including first optical branching means for splitting said input light into a first beam and a second beam; optical semiconductor amplifier means for amplifying said first beam; first photodetector means for receiving said second beam and generating a corresponding first electric signal; second optical coupling means including second optical branching means for splitting a third beam of light into a fourth beam and a fifth beam, wherein said third beam is an amplification of said first beam by said optical semiconductor amplifier element; second photodetector means for receiving said fifth beam and generating a corresponding second electric signal; an output waveguide medium for receiving said fourth beam; and feedback control circuit means for controlling an injection current to said optical semiconductor amplifier means in response to said first electric signal and said second electric signal.
Claim 3
Dependent Claim 17 words
An amplifier as claimed in claim 1, wherein said first optical branching means comprises a transparent grating.
Claim 4
Dependent Claim 17 words
An amplifier as claimed in claim 1, wherein said first optical branching means comprises a half mirror.
Claim 5
Dependent Claim 16 words
An amplifier as claimed in claim 1, wherein said second optical branching means comprises a half-mirror.
Claim 6
Dependent Claim 25 words
An amplifier as claimed in claim 1, wherein said optical semiconductor amplifier element and said first and second photodetectors are aligned in a single plane.
Claim 7
Dependent Claim 41 words
An amplifier as claimed in claim 1, wherein a plurality of assemblies each comprising said input optical waveguide medium, said first and second optical coupling means, said optical semiconductor amplifier element and said output optical waveguide medium are arranged in parallel.
Claim 8
Dependent Claim 51 words
An amplifier as claimed in claim 1, wherein said first and second optical coupling means and said first and second optical branching means thereof are constituted by optical waveguides formed on a single substrate; said optical semiconductor amplifier element and said first and second photodetectors being arranged on said single substrate.
Claim 9
Dependent Claim 27 words
An amplifier as claimed in claim 1, wherein at least one of said input optical waveguide medium and said output optical waveguide medium comprises an optical fiber.
Claim 10
Dependent Claim 31 words
An amplifier as claimed in claim 1, wherein at least one of said input optical waveguide medium and said output optical waveguide medium comprises an optical waveguide formed on a substrate.
Claim 11
Dependent Claim 54 words
An amplifier as claimed in claim 1, wherein said input optical waveguide medium and said output optical waveguide medium comprise optical waveguides formed on a single substrate. said first optical coupling means, said optical semiconductor amplifier element, said first photodetector, said second optical coupling means and said second photodetector being provided on said substrate.
Claim 12
Dependent Claim 28 words
An amplifier as claimed in claim 10, wherein said substrate comprises a silicon substrate, said optical waveguides comprising a core made of silicon dioxide deposited on said substrate.
Claim 13
Dependent Claim 27 words
An amplifier as claimed in claim 10, wherein said first optical branching means comprises an optical waveguide formed on said substrate and including a Y branch portion.
Claim 14
Dependent Claim 37 words
An amplifier as claimed in claim 10, wherein said second optical branching means comprises an optical waveguide formed on said substrate and including a Y branch portion, and a half mirror positioned at said Y branch portion.
Claim 15
Dependent Claim 38 words
An amplifier as claimed in claim 9, wherein said input optical waveguide and said output optical waveguide are respectively optically coupled to an input optical fiber and an output optical fiber located outside of said optical semiconductor amplifier.
Claim 16
Dependent Claim 27 words
An amplifier as claimed in claim 14, wherein said input optical fiber and said output optical fiber are each received in a groove formed in said substrate.
Claim 17
Dependent Claim 17 words
An amplifier as claimed in claim 9, wherein said feedback control circuit is provided on said substrate.
Claim 18
Dependent Claim 87 words
An optical semiconductor amplifier comprising: an input optical waveguide medium for feeding input light; optical semiconductor amplifier means for amplifying a beam of said input light; photodetector means for receiving a part of said beam of said input light and generating a corresponding electric signal; an output optical waveguide medium for receiving an amplified beam of said input light from said optical semiconductor amplifier means; and feedback control circuit means for controlling an injection current to said optical semiconductor amplifier means in response to said electric signal.
Claim 19
Dependent Claim 87 words
An optical semiconductor amplifier comprising: an input optical waveguide medium for feeding input light; optical semiconductor amplifier means for amplifying a beam of said input light; photodetector means for receiving a part of said beam of said input light and generating a corresponding electric signal; an output optical waveguide medium for receiving an amplified beam of said input light from said optical semiconductor amplifier means; and feedback control circuit means for controlling an injection current to said optical semiconductor amplifier means in response to said electric signal.
Claim 20
Dependent Claim 135 words
An optical semiconductor amplifier comprising: an input optical waveguide medium for feeding input light; optical semiconductor amplifier means for amplifying at least a first part of a beam of said input light; first photodetector means for receiving a second part of said beam of said input light and generating a corresponding first electric signal; second photodetector means for receiving a first part of an amplified beam of said input light from said optical semiconductor amplifier means and generating a corresponding second electric signal; an output optical waveguide medium for receiving a second part of said amplified beam of said input light from said optical semiconductor amplifier means; and feedback control circuit means for controlling an injection current to said optical semiconductor amplifier means in response to said first electric signal and said second electric signal.
Claim 21
Dependent Claim 135 words
An optical semiconductor amplifier comprising: an input optical waveguide medium for feeding input light; optical semiconductor amplifier means for amplifying at least a first part of a beam of said input light; first photodetector means for receiving a second part of said beam of said input light and generating a corresponding first electric signal; second photodetector means for receiving a first part of an amplified beam of said input light from said optical semiconductor amplifier means and generating a corresponding second electric signal; an output optical waveguide medium for receiving a second part of said amplified beam of said input light from said optical semiconductor amplifier means; and feedback control circuit means for controlling an injection current to said optical semiconductor amplifier means in response to said first electric signal and said second electric signal.

References Cited (Backward Citations)

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EP0305995A2 Cited
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DE3731311A1 Cited
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EP0377948A2 Cited
JPH02291510A Cited
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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) 1998-05-08 1998-11-07 1999-05-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-05-08 2002-11-07 2003-05-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-05-08 2006-11-07 2007-05-09 $7700.00 Window Closed / Lapsed

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