Patent US4933947A successfully refreshed from Google Patents.
US4933947A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency conversion of optical radiation
Assignee: Cisco Technology Inc
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Filing: 1989-05-18
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Granted: 1990-06-12
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Expires: 2009-05-18
Abstract
Abstract An intracavity frequency-modified laser of improved amplitude stability is obtained by substantially eliminating spatial hole burning in the lasant material and maintaining the optical cavity of the laser at a temperature which results in substantially noise-free generation of output radiation.
Inventors
- 👤 Douglas W. Anthon
- 👤 Donald L. Sipes, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:52
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/106; H01S3/108; H01S3/109; H01S2301/00; H01S2301/02; H01S3/102; H01S3/1028
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
148 words
An optically pumped solid state laser comprising: (a) an optical cavity for optical radiation of a first frequency; (b) optical pumping means for generating optical pumping radiation which comprises a laser diode; (c) solid lasant material which is disposed within said optical cavity, positioned to receive pumping radiation from said optical pumping means, and effective for generating coherent optical radiation of said first frequency upon receiving said pumping radiation; (d) means for substantially eliminating spatial hole burning in the lasant material during said generation of optical radiation of a first frequency; (e) nonlinear optical means within the optical cavity for converting said optical radiation of a first frequency into coherent optical radiation of a second frequency; and (f) temperature control means for maintaining the temperature of said optical cavity at a value within a range, which results in substantially noise-free generation of said radiation of a second frequency.
Claim 2
Dependent Claim
148 words
An optically pumped solid state laser comprising: (a) an optical cavity for optical radiation of a first frequency; (b) optical pumping means for generating optical pumping radiation which comprises a laser diode; (c) solid lasant material which is disposed within said optical cavity, positioned to receive pumping radiation from said optical pumping means, and effective for generating coherent optical radiation of said first frequency upon receiving said pumping radiation; (d) means for substantially eliminating spatial hole burning in the lasant material during said generation of optical radiation of a first frequency; (e) nonlinear optical means within the optical cavity for converting said optical radiation of a first frequency into coherent optical radiation of a second frequency; and (f) temperature control means for maintaining the temperature of said optical cavity at a value within a range, which results in substantially noise-free generation of said radiation of a second frequency.
Claim 3
Dependent Claim
21 words
The laser of claim 1 wherein the optical cavity is a standing wave cavity for said radiation of a first frequency.
Claim 4
Dependent Claim
22 words
The laser of claim 2 wherein the optical cavity is a linear standing wave cavity for said radiation of a first frequency.
Claim 5
Dependent Claim
23 words
The laser of claim 2 wherein said means for eliminating spatial hole burning comprises a pair of quarter-wave plates within said optical cavity.
Claim 6
Dependent Claim
19 words
The laser of claim 4 wherein said lasant material and nonlinear optical means are positioned between said quarter-wave plates.
Claim 7
Dependent Claim
41 words
The laser of claim 1 wherein said optical cavity is of a ring-type and said means for eliminating spatial hole burning comprises unidirectional optical gate means for effecting unidirectional circulation of said radiation of a first frequency within the optical cavity.
Claim 8
Dependent Claim
23 words
The laser of claim 6 wherein said unidirectional optical gate means is comprised of a polarizer, a half-wave plate, and a Faraday rotator.
Claim 9
Dependent Claim
16 words
The laser of claim 1 wherein said second frequency is twice that of said first frequency.
Claim 10
Dependent Claim
20 words
The laser of claim 1 wherein said radiation of a first frequency is comprised of at least two longitudinal modes.
Claim 11
Dependent Claim
16 words
The laser of claim 1 wherein said nonlinear optical material is comprised of potassium titanyl phosphate.
Claim 12
Dependent Claim
14 words
The laser of claim 1 wherein said lasant material is comprised of neodymium-doped YAG.
Claim 13
Independent Claim
160 words
A method for generating coherent optical radiation which comprises: (a) generating coherent optical radiation of a first frequency from solid lasant material within an optical cavity for said radiation of a first frequency; (b) substantially preventing spatial hole burning in the lasant material during said generation of radiation of a first frequency with spatial hole burning suppression means; (c) converting said optical radiation of a first frequency into coherent optical radiation of a second frequency within said optical cavity with nonlinear optical means; (d) withdrawing said optical radiation of a second frequency from said optical cavity as output radiation; (e) measuring the noise in said output radiation as a function of the temperature of said optical cavity; (f) determining a temperature range for said optical cavity over which said output radiation is substantially noisefree; and (g) maintaining the temperature of said optical cavity at a value which is within said determined temperature range during subsequent production of said output radiation.
Claim 14
Independent Claim
160 words
A method for generating coherent optical radiation which comprises: (a) generating coherent optical radiation of a first frequency from solid lasant material within an optical cavity for said radiation of a first frequency; (b) substantially preventing spatial hole burning in the lasant material during said generation of radiation of a first frequency with spatial hole burning suppression means; (c) converting said optical radiation of a first frequency into coherent optical radiation of a second frequency within said optical cavity with nonlinear optical means; (d) withdrawing said optical radiation of a second frequency from said optical cavity as output radiation; (e) measuring the noise in said output radiation as a function of the temperature of said optical cavity; (f) determining a temperature range for said optical cavity over which said output radiation is substantially noisefree; and (g) maintaining the temperature of said optical cavity at a value which is within said determined temperature range during subsequent production of said output radiation.
Claim 15
Dependent Claim
44 words
The method of claim 12 wherein said second frequency is twice that of said first frequency wherein said temperature range is determined by measuring the noise content of said radiation of a second frequency as a function of the temperature of said optical cavity.
Claim 16
Dependent Claim
20 words
The method of claim 12 wherein said radiation of a first frequency is comprised of at least two longitudinal modes.
Claim 17
Dependent Claim
21 words
The method of claim 12 wherein the optical cavity is a standing wave cavity for said radiation of a first frequency.
Claim 18
Dependent Claim
22 words
The method of claim 15 wherein the optical cavity is a linear standing wave cavity for said radiation of a first frequency.
Claim 19
Dependent Claim
22 words
The method of claim 15 wherein said spatial hole burning suppression means comprises a pair of quarter-wave plates within said optical cavity.
Claim 20
Dependent Claim
19 words
The method of claim 17 wherein said lasant material and nonlinear optical means are positioned between said quarter-wave plates.
Claim 21
Dependent Claim
41 words
The method of claim 12 wherein said optical cavity is of a ring-type and said means for eliminating spatial hole burning comprises unidirectional optical gate means for effecting unidirectional circulation of said radiation of a first frequency within the optical cavity.
Claim 22
Dependent Claim
22 words
The method of claim 6 wherein said unidirectional optical gate is comprised of a polarizer, a halfwave plate, and a Faraday rotator.
Claim 23
Dependent Claim
26 words
The method of claim 12 which additionally comprises optically pumping said lasant material with optical pumping means wherein said optical pumping means comprises a laser diode.
Claim 24
Dependent Claim
15 words
The method of claim 21 wherein said optical pumping means comprises a laser diode array.
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) | 1993-06-11 | 1993-12-11 | 1994-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-11 | 1997-12-11 | 1998-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-11 | 2001-12-11 | 2002-06-12 | $7700.00 | Window Closed / Lapsed |