Patent US5430748A successfully refreshed from Google Patents.
US5430748A
Expired / Lapsed
US
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Laser system with phase-conjugator-enhanced output
Assignee: University of Southern California
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Filing: 1994-01-21
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Granted: 1995-07-04
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Expires: 2014-01-21
Abstract
Abstract A laser system includes a linear array of broad area lasers. Such a laser source produces a beam that has a polarization axis in the direction in which the array extends and a coherency axis orthogonal to that. The laser is injection locked by phase conjugating a portion of the array's light output. The phase conjugator has a conjugation axis. The coherency axis is aligned with this conjugation axis. External cavity optics include a polarization rotator to align the polarization axis with the coherency axis before the beam reaches the phase conjugator. Thus, the polarization, coherency, and conjugation axes are all aligned, optimizing the action of the phase conjugator. The approach works in both a single-beam and a dual-beam phase conjugation mode. The result is a laser system output of higher intensity, greater coherence, and a narrower frequency range.
Inventors
- 👤 Stuart MacCormack
- 👤 Jack L. Feinberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 17:29
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/10076; H01S5/00; H01S5/40; H01S5/4025; H01S5/10; H01S5/14; H01S5/145; H01S5/20; H01S5/2036; H01S5/4006; H01S5/4031; H01S5/4062
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
114 words
A laser system comprising: a laser source for providing light having a propagation vector, a polarization axis, and a coherency axis, said light being propagated along said propagation vector, said light being polarized along said polarization axis, said light having maximum coherency along said coherency axis, said polarization axis and said coherency axis being generally orthogonal to said propagation vector, said coherency axis and said polarization axis having a discrepancy angle of at least 45° therebetween; a phase conjugator having a conjugation axis; and external cavity optics optically coupling a portion of the output of said laser source to said phase conjugator so that said coherency axis is substantially aligned with said conjugation axis.
Claim 2
Dependent Claim
114 words
A laser system comprising: a laser source for providing light having a propagation vector, a polarization axis, and a coherency axis, said light being propagated along said propagation vector, said light being polarized along said polarization axis, said light having maximum coherency along said coherency axis, said polarization axis and said coherency axis being generally orthogonal to said propagation vector, said coherency axis and said polarization axis having a discrepancy angle of at least 45° therebetween; a phase conjugator having a conjugation axis; and external cavity optics optically coupling a portion of the output of said laser source to said phase conjugator so that said coherency axis is substantially aligned with said conjugation axis.
Claim 3
Dependent Claim
40 words
A laser system as recited in claim 1 wherein said optics includes a polarization rotator for rotating said polarization axis so that said discrepancy angle is reduced and so that said polarization axis is substantially aligned with said conjugation axis.
Claim 4
Dependent Claim
19 words
A laser system as recited in claim 2 wherein said laser source is a linear array of semiconductor lasers.
Claim 5
Dependent Claim
29 words
A laser system as recited in claim 2 wherein said phase conjugator includes a BaTiO 3 crystal and wherein said conjugation axis is the c axis of that crystal.
Claim 6
Dependent Claim
37 words
A laser system as recited in claim 2 wherein said optics include a cylindrical lens arranged to narrow the cross section subtended by said light in the plane defined by said propagation vector and said coherency axis.
Claim 7
Dependent Claim
17 words
A laser system as recited in claim 2 wherein said phase conjugator operates in a single-beam mode.
Claim 8
Dependent Claim
17 words
A laser system as recited in claim 2 wherein said phase conjugator operates in a dual-beam mode.
Claim 9
Dependent Claim
21 words
A laser system as recited in claim 7 wherein a single-mode semiconductor laser provides a second beam for said dual-beam mode.
Claim 10
Dependent Claim
33 words
A laser system as recited in claim 8 further comprising means for controlling the amplitude of said single-mode semiconductor laser so as to affect the amplitude of the output of said laser system.
Claim 11
Dependent Claim
33 words
A laser system as recited in claim 8 further comprising means for controlling the frequency of said single-mode semiconductor laser so as to affect the frequency of the output of said laser system.
Claim 12
Independent Claim
82 words
A method of providing a laser output, said method comprising the steps of: generating a laser beam having a coherency axis and a polarization axis defining a discrepancy angle therebeteween of at least 45°; optically guiding a portion of said beam to a phase conjugator having a conjugation axis so that said coherency axis is substantially aligned with said conjugation axis; phase conjugating said portion of said beam; and directing the phase conjugated beam back to the source of said laser beam.
Claim 13
Independent Claim
82 words
A method of providing a laser output, said method comprising the steps of: generating a laser beam having a coherency axis and a polarization axis defining a discrepancy angle therebeteween of at least 45°; optically guiding a portion of said beam to a phase conjugator having a conjugation axis so that said coherency axis is substantially aligned with said conjugation axis; phase conjugating said portion of said beam; and directing the phase conjugated beam back to the source of said laser beam.
Claim 14
Dependent Claim
34 words
A method as recited in claim 11 wherein said guiding step further involves rotating said polarization axis relative to said coherency axis so that said polarization axis is substantially aligned with said conjugation axis.
Claim 15
Dependent Claim
18 words
A method as recited in claim 12 wherein said laser source is a linear array of semiconductor lasers.
Claim 16
Dependent Claim
26 words
A method as recited in claim 12 wherein said phase conjugator includes a BaTiO3 crystal and wherein said conjugation is the c axis of that crystal.
Claim 17
Dependent Claim
16 words
A method as recited in claim 12 wherein said phase conjugating operates in a single-beam mode.
Claim 18
Dependent Claim
16 words
A method as recited in claim 12 wherein said phase conjugating operates in a dual-beam mode.
Claim 19
Dependent Claim
22 words
A method as recited in claim 16 wherein a second beam for said dual-mode operation is provided by a single mode laser.
Claim 20
Dependent Claim
32 words
A method as recited in claim 17 further comprising a step of adjusting the amplitude of said single-mode laser so as to increase the amplitude of the output of said laser system.
Claim 21
Dependent Claim
32 words
A method as recited in claim 17 further comprising a step of adjusting the amplitude of said single-mode laser so as to control the frequency of the output of said laser system.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-07-03 | 1999-01-02 | 1999-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-07-03 | 2003-01-02 | 2003-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-07-03 | 2007-01-02 | 2007-07-04 | $7700.00 | Window Closed / Lapsed |