US5559816A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Narrow-band laser apparatus
Assignee: LAMBDA PHYSKI GESELLSCHAFT ZUR HERSTELLUNG VON LASERN MBH
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Filing: 1995-05-30
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Granted: 1996-09-24
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Expires: 2015-05-30
Abstract
Abstract A narrow-band laser apparatus comprises an optical resonator including first and second reflectors for reflecting radiation, a laser medium for amplifying radiation in said resonator and an etalon for selecting a given wavelength component from said radiation. A polarizing beam splitter is provided for linearly polarizing said radiation and also for acting as an output coupler. In order to obtain very narrow bandwidth radiation of high intensity, a Faraday rotator is provided for rotating the plane of polarization while maintaining the linear polarization thereby allowing a second wavelength selection element (such as a grating) to be efficiently employed to further narrow the output of the laser.
Inventors
- 👤 Dirk Basting
- 👤 Jurgen Kleinschmidt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 05:28
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/05; H01S3/08; H01S3/08018; H01S3/08022; H01S3/08031; H01S3/08036; G; G03; G03F; G03F7/00; G03F7/70; G03F7/70008; G03F7/70025; G03F7/70483; G03F7/7055; G03F7/70566; G03F7/70575; H01S3/10; H01S3/106; H01S3/1066; H01S3/08004; H01S3/08009; H01S3/14; H01S3/22; H01S3/223; H01S3/225
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
154 words
A narrow band laser apparatus comprising: a resonant cavity including a pair of reflective end mirrors; a gain medium located within said resonant cavity; means for exciting the gain medium to generate a laser beam; means for linearly polarizing the laser beam; first line narrowing means located between the polarizing means and one end mirror; means for controllably rotating the plane of polarization of the light beam while maintaining the linear polarization of the beam, said rotation means being located between said polarizing means and the ocher end mirror; means connected to the rotating means for independently varying the amount the rotation means rotates the plane of polarization of the laser beam; and means for coupling the laser beam out the cavity, with the percentage of the light beam that is coupled out of the cavity being a function of the amount the rotation means rotates the plane of polarization of the laser beam.
Claim 2
Dependent Claim
154 words
A narrow band laser apparatus comprising: a resonant cavity including a pair of reflective end mirrors; a gain medium located within said resonant cavity; means for exciting the gain medium to generate a laser beam; means for linearly polarizing the laser beam; first line narrowing means located between the polarizing means and one end mirror; means for controllably rotating the plane of polarization of the light beam while maintaining the linear polarization of the beam, said rotation means being located between said polarizing means and the ocher end mirror; means connected to the rotating means for independently varying the amount the rotation means rotates the plane of polarization of the laser beam; and means for coupling the laser beam out the cavity, with the percentage of the light beam that is coupled out of the cavity being a function of the amount the rotation means rotates the plane of polarization of the laser beam.
Claim 3
Dependent Claim
22 words
A laser as recited in claim 1 wherein said polarizing means and said coupling means are defined by a polarizing beam splitter.
Claim 4
Dependent Claim
16 words
A laser as recited in claim 1 wherein said first line narrowing means is an etalon.
Claim 5
Dependent Claim
20 words
A laser as recited in claim 1 wherein said means for rotating the plane of polarization is a Faraday rotator.
Claim 6
Dependent Claim
24 words
A laser as recited in claim 4 further including a second line narrowing means located between said Faraday rotator and the other end mirror.
Claim 7
Dependent Claim
15 words
A narrow-band laser apparatus according to claim 1 wherein said laser is an excimer laser.
Claim 8
Dependent Claim
22 words
A narrow-band laser apparatus according to claim 1, wherein said resonant cavity includes expanding means for expanding the width of said radiation.
Claim 9
Dependent Claim
14 words
A narrow-band laser apparatus according to claim 7, wherein said expanding means comprises prisms.
Claim 10
Dependent Claim
32 words
A narrow-band laser apparatus according to claim 1, wherein said resonant cavity includes first and second expanding means and wherein said gain medium is interposed between said first and second expanding means.
Claim 11
Dependent Claim
14 words
A narrow-band laser apparatus according to claim 9, wherein said expanding means comprise prisms.
Claim 12
Dependent Claim
26 words
A narrow-band laser apparatus according to claim 1, wherein said resonant cavity further includes two slit-shaped diaphragms, two polarizing beam splitters and an expanding optical means.
Claim 13
Dependent Claim
29 words
A narrow-band laser apparatus according to claim 11, wherein said two slit-shaped diaphragms define a resonator axis which is tilted relative to a longitudinal axis of said laser medium.
Claim 14
Dependent Claim
143 words
A narrow band laser apparatus comprising: a resonant cavity including a pair of reflective end mirrors; a gain medium located within said resonant cavity; means for exciting the gain medium to generate a laser beam; a polarizing beam splitter for linearly polarizing the laser beam; an etalon located between the beam splitter and one end mirror; a Faraday rotator for rotating the plane of polarization of the light beam while maintaining the linear polarization of the beam and located between said beam splitter and said other end mirror and wherein said beam splitter further functions to couple the laser beam out of the cavity, with the percentage of output coupling being a function of the amount the Faraday rotator rotates the plane of polarization of the laser beam; and a line narrowing means located between the faraday rotator and the other end mirror.
Claim 15
Dependent Claim
143 words
A narrow band laser apparatus comprising: a resonant cavity including a pair of reflective end mirrors; a gain medium located within said resonant cavity; means for exciting the gain medium to generate a laser beam; a polarizing beam splitter for linearly polarizing the laser beam; an etalon located between the beam splitter and one end mirror; a Faraday rotator for rotating the plane of polarization of the light beam while maintaining the linear polarization of the beam and located between said beam splitter and said other end mirror and wherein said beam splitter further functions to couple the laser beam out of the cavity, with the percentage of output coupling being a function of the amount the Faraday rotator rotates the plane of polarization of the laser beam; and a line narrowing means located between the faraday rotator and the other end mirror.
Claim 16
Dependent Claim
15 words
A narrow-band laser apparatus according to claim 13, wherein said laser is an excimer laser.
Claim 17
Dependent Claim
168 words
A narrow band laser apparatus comprising: a resonant cavity including a pair of reflective end mirrors; a gain medium located within said resonant cavity; means for exciting the gain medium to generate a laser beam; means for linearly polarizing the laser beam; first line narrowing means located between the polarizing means and one end mirror; means for rotating the plane of polarization of the light beam while maintaining the linear polarization of the beam, said rotation means being located between said polarizing means and the other end mirror; second line narrowing means located between said rotating means and the other end mirror, said second line narrowing means being of the type which requires substantially linear polarization interaction to avoid reducing the efficiency of the system; and means for coupling the laser beam out of the cavity, with the percentage of the light beam that is coupled out of the cavity being a function of the amount the rotation means rotates the plane of polarization of the laser beam.
Claim 18
Dependent Claim
168 words
A narrow band laser apparatus comprising: a resonant cavity including a pair of reflective end mirrors; a gain medium located within said resonant cavity; means for exciting the gain medium to generate a laser beam; means for linearly polarizing the laser beam; first line narrowing means located between the polarizing means and one end mirror; means for rotating the plane of polarization of the light beam while maintaining the linear polarization of the beam, said rotation means being located between said polarizing means and the other end mirror; second line narrowing means located between said rotating means and the other end mirror, said second line narrowing means being of the type which requires substantially linear polarization interaction to avoid reducing the efficiency of the system; and means for coupling the laser beam out of the cavity, with the percentage of the light beam that is coupled out of the cavity being a function of the amount the rotation means rotates the plane of polarization of the laser beam.
Claim 19
Dependent Claim
22 words
A laser as recited in claim 15 wherein said polarizing means and said coupling means are defined by a polarizing beam splitter.
Claim 20
Dependent Claim
16 words
A laser as recited in claim 15 wherein said first line narrowing means is an etalon.
Claim 21
Dependent Claim
20 words
A laser as recited in claim 15 wherein said means for rotating the plane of polarization is a Faraday rotator.
Claim 22
Dependent Claim
15 words
A narrow-band laser apparatus according to claim 15 wherein said laser is an excimer laser.
Claim 23
Dependent Claim
18 words
A narrow-band laser apparatus as recited in claim 15 wherein said second line narrowing element is a grating.
Claim 24
Dependent Claim
18 words
A narrow-band laser apparatus as recited in claim 15 wherein said second line narrowing element is a prism.
Claim 25
Dependent Claim
22 words
A narrow-band laser apparatus according to claim 15, wherein said resonant cavity includes expanding means for expanding the width of said radiation.
Claim 26
Dependent Claim
14 words
A narrow-band laser apparatus according to claim 22, wherein said expanding means comprises prisms.
Claim 27
Dependent Claim
32 words
A narrow-band laser apparatus according to claim 15, wherein said resonant cavity includes first and second expanding means and wherein said gain medium is interposed between said first and second expanding means.
Claim 28
Dependent Claim
14 words
A narrow-band laser apparatus according to claim 24, wherein said expanding means comprise prisms.
Claim 29
Dependent Claim
26 words
A narrow-band laser apparatus according to claim 15, wherein said resonant cavity further includes two slit-shaped diaphragms, two polarizing beam splitters and an expanding optical means.
Claim 30
Dependent Claim
29 words
A narrow-band laser apparatus according to claim 26, wherein said two slit-shaped diaphragms define a resonator axis which is tilted relative to a longitudinal axis of said laser medium.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1999-09-24 | 2000-03-25 | 2000-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-09-24 | 2004-03-25 | 2004-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-09-24 | 2008-03-25 | 2008-09-24 | $7700.00 | Window Closed / Lapsed |