Patent US5117469A successfully refreshed from Google Patents.
US5117469A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polarization-dependent and polarization-diversified opto-electronic devices using a strained quantum well
Assignee: Nytell Software LLC
•
Filing: 1991-02-01
•
Granted: 1992-05-26
•
Expires: 2011-02-01
Abstract
Abstract A polarized semiconductive optical detector, laser, or amplifier in which the active layer includes a strained quantum well such that the strain splits the valence band so as to provide anisotropic absorption (and gain under population inversion) for two linear polarizations of light. The bands are split about the energy of the light so that the polarized device absorbs and thus detects, amplifies, or lases only one of the polarizations. To form a polarization-diversity detector, the polarized detector is set serially first on an optical waveguide, and a non-polarized or oppositely polarized detector is set serially second on the waveguide so as to detect the non-absorbed light of the other polarization. Such a polarization-diversity detector can be used to form a simple optical-disk pickup head or an array of pickup heads. A pair of such polarization diversity detectors can advantageously be comined with a 3 dB splitter and a local-oscillator laser to form a simple coherent receiver. by the same techniqes, dual-polarization lasers, polarization-multiplexed transceivers, and polarization-insensitive amplifiers are made possible.
Inventors
- 👤 Kwok-Wai Cheung
- 👤 Chung-En Zah
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:57
CPC Classifications
B; B82; B82Y; B82Y20/00; H; H01; H01S; H01S5/00; H01S5/0014; H01S5/30; H01S5/34; H01S5/343; H01S5/34313; H01S5/50; H01S5/5036; H04; H04B; H04B10/00; H04B10/60; H04B10/61; H04B10/614; H04B10/65; H10; H10F; H10F77/00; H10F77/10; H10F77/14; H01S2301/00; H01S2301/14; H01S5/0028; H01S5/02; H01S5/026; H01S5/0262; H01S5/0264; H01S5/06; H01S5/062; H01S5/06233; H01S5/06236; H01S5/0625; H01S5/3403; H01S5/3404; H01S5/34306; H01S5/40; H01S5/4025; H01S5/4031
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
118 words
A polarized opto-electronic system, comprising: a waveguide formed in and laterally defined within the surface of a substrate for carrying light having a characteristic energy; a first opto-electronic device formed adjacent to a first portion of said waveguide and including an active strained quantum-well layer interacting with said light and having a first transition energy for light of a first polarization and having a second transition energy for light of a second orthogonal polarization, said characteristic energy falling between said first and second transition energies; and a second opto-electronic device formed adjacent to a second portion of said waveguide and including an active layer having different strain characteristics than said strained quantum-well layer of said first opto-electronic device.
Claim 2
Dependent Claim
118 words
A polarized opto-electronic system, comprising: a waveguide formed in and laterally defined within the surface of a substrate for carrying light having a characteristic energy; a first opto-electronic device formed adjacent to a first portion of said waveguide and including an active strained quantum-well layer interacting with said light and having a first transition energy for light of a first polarization and having a second transition energy for light of a second orthogonal polarization, said characteristic energy falling between said first and second transition energies; and a second opto-electronic device formed adjacent to a second portion of said waveguide and including an active layer having different strain characteristics than said strained quantum-well layer of said first opto-electronic device.
Claim 3
Dependent Claim
19 words
A polarized opto-electronic system as recited in claim 1, wherein said second opto-electronic device includes an active quantum-well layer.
Claim 4
Dependent Claim
31 words
A polarized opto-electronic system as recited in claim 2, wherein said quantum-well layer in said second opto-electronic device is strained oppositely from said strained quantum-well layer of said first opto-electronic device.
Claim 5
Dependent Claim
39 words
A dual-polarization laser including the polarized opto-electronic system recited in claim 3, wherein said first and second opto-electronic devices further comprise optical feedback means and further comprising biasing means for biasing said first and second opto-electronic devices as lasers.
Claim 6
Dependent Claim
29 words
A dual-polarization optical amplifier including the polarized opto-electronic system recited in claim 1 and further comprising biasing means for biasing said first and second opto-electronic devices as optical amplifiers.
Claim 7
Dependent Claim
56 words
A polarization-multiplexed transceiver including said polarized opto-electronic system recited in claim 1, wherein a first one of said first and second opto-electronic devices includes optical feedback means and further comprising biasing means for biasing said first one as a laser and for biasing a second one of said first and second opto-electronic devices as a detector.
Claim 8
Dependent Claim
160 words
A polarization-diversified detector, comprising: a waveguide formed in the surface of a substrate for carrying light having a characteristic energy; a first opto-electronic device formed adjacent to a first portion of said waveguide and including an active strained quantum-well layer interacting with said light and having a first transition energy for light of a first polarization and having a second transition energy for light of a second orthogonal polarization, said characteristic energy falling between said first and second transition energies; a second opto-electronic device formed adjacent to a second portion of said waveguide and including an active layer having different strain characteristics than said strained quantum-well layer of said first opto-electronic device; and biasing means to bias said first and second opto-electronic devices as first and second detectors, and wherein said waveguide receives said light on a first side of said first detector and said second detector is disposed on said waveguide on a second side of said first detector.
Claim 9
Dependent Claim
160 words
A polarization-diversified detector, comprising: a waveguide formed in the surface of a substrate for carrying light having a characteristic energy; a first opto-electronic device formed adjacent to a first portion of said waveguide and including an active strained quantum-well layer interacting with said light and having a first transition energy for light of a first polarization and having a second transition energy for light of a second orthogonal polarization, said characteristic energy falling between said first and second transition energies; a second opto-electronic device formed adjacent to a second portion of said waveguide and including an active layer having different strain characteristics than said strained quantum-well layer of said first opto-electronic device; and biasing means to bias said first and second opto-electronic devices as first and second detectors, and wherein said waveguide receives said light on a first side of said first detector and said second detector is disposed on said waveguide on a second side of said first detector.
Claim 10
Dependent Claim
21 words
A polarization-diversified detector as recited in claim 7, wherein said active layer of said second detector includes no strained quantum-well layer.
Claim 11
Dependent Claim
31 words
A polarization-diversified detector as recited in claim 7, wherein said active layer of said second detector includes a quantum-well layer strained oppositely from said strained quantum-well layer of said first detector.
Claim 12
Dependent Claim
77 words
A coherent polarization-diversified receiver, comprising: a first polarization-diversified detector as recited in claim 7 whose waveguide has an input end for receiving an input signal; a local-oscillator laser; a second polarization-diversified detector as recited in claim 7 whose waveguide has an input end coupled to an output of said local-oscillator laser; and an optical coupler for optically coupling said waveguides of said first and second polarization-diversified detectors and disposed between said input ends and said opto-electronic devices.
Claim 13
Dependent Claim
118 words
An optical pickup, comprising: a substrate; a semiconductor laser formed in said substrate and emitting light from a periphery of said substrate; an optical waveguide formed in said substrate and extending from said periphery to a central portion of said substrate; a first optical detector formed adjacent to a first linear portion of said waveguide; a second optical detector formed adjacent to a second linear portion of said waveguide, wherein said first and second optical detectors have differing sensitivities to at least one polarization state of light propagating in said waveguide; and electrical processing means for comparing outputs of said first and second optical detectors to thereby determine a polarization rotation of said light emitted by said laser.
Claim 14
Dependent Claim
118 words
An optical pickup, comprising: a substrate; a semiconductor laser formed in said substrate and emitting light from a periphery of said substrate; an optical waveguide formed in said substrate and extending from said periphery to a central portion of said substrate; a first optical detector formed adjacent to a first linear portion of said waveguide; a second optical detector formed adjacent to a second linear portion of said waveguide, wherein said first and second optical detectors have differing sensitivities to at least one polarization state of light propagating in said waveguide; and electrical processing means for comparing outputs of said first and second optical detectors to thereby determine a polarization rotation of said light emitted by said laser.
Claim 15
Dependent Claim
45 words
An optical pickup as recited in claim 11, wherein said first optical detector has a first active layer having a quantum well in compressive strain and wherein said second optical detector has a second active layer with different strain characteristics than said first active layer.
Claim 16
Dependent Claim
16 words
An optical pickup as recited in claim 12, wherein said second active layer is substantially unstrained.
Claim 17
Dependent Claim
21 words
An optical pickup as recited in claim 12, wherein said second active layer has a quantum well in biaxial tensile strain.
References Cited (Backward Citations)
US4746181A
Cited
US4612645A
Cited
US4827320A
Cited
US4941025A
Cited
US4904045A
Cited
US4984242A
Cited
US5021360A
Cited
US4952792A
Cited
US5040186A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-05-26 | 1995-11-25 | 1996-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-05-26 | 1999-11-25 | 2000-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-05-26 | 2003-11-25 | 2004-05-26 | $7700.00 | Window Closed / Lapsed |