US3644841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency-stabilized single mode ring lasers
Assignee: AT&T Inc
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Filing: 1970-05-04
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Granted: 1972-02-22
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Expires: 1990-05-04
Abstract
Abstract A sensitive frequency discriminant based on the gain profile of the active medium can be obtained in an ion ring laser having a Doppler-broadened emission line by promoting stable competition between oppositely propagating traveling-wave components of a single transverse mode and by tuning an auxiliary ring resonator that determines the frequency of the primary ring resonator to maintain substantially equal intensities of the oppositely propagating waves. The discriminant is then used to stabilize the auxiliary ring resonator. The primary ring resonator is stabilized by locking one of its resonant frequencies to a resonance of the auxiliary ring resonator with a feedback circuit. Stable competition is achieved by providing a selected gain anisotropy of the ion laser active medium. The anisotropy is selected to be sufficiently large to inhibit the quenching of one of the oppositely propagating waves by the other, even though they have the same frequency. In the typical case of a gas ion laser, a substantial ion drift rate provides the gain anisotropy.
Inventors
- 👤 Peter William Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:38
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/05; H01S3/08; H01S3/081; H01S3/083; H01S3/10; H01S3/13; H01S3/139; H01S3/1396
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
199 words
Apparatus for generating frequency-controlled coherent electromagnetic wave energy, of the type comprising a primary optical ring resonator, an active medium disposed in said primary resonator, said medium being capable of supporting oppositely propagating travelingwave oscillations within said resonator, means for pumping said active medium at a level sufficient to support said oscillations within said active medium, an auxiliary optical ring resonator disposed within said primary ring resonator and coupled to said primary ring resonator by beam splitters oriented to direct out of said apparatus oscillations that are not resonant in both said primary and said auxiliary resonators, feedback means for tuning said primary resonator to stabilize its resonance with respect to the resonances of said auxiliary resonator, said apparatus being characterized, in that, said active medium is an ionized gaseous medium, said pumping means promotes ion drift within said active medium to provide a selected splitting of peak gains for said oppositely propagating oscillations, said splitting being selected to provide a smoothly varying intensity difference of said oppositely propagating oscillations with tuning of said auxiliary resonator, and feedback means responsive to said intensity difference for tuning said auxiliary resonator to stabilize the intensity difference of the oppositely propagating waves.
Claim 2
Dependent Claim
199 words
Apparatus for generating frequency-controlled coherent electromagnetic wave energy, of the type comprising a primary optical ring resonator, an active medium disposed in said primary resonator, said medium being capable of supporting oppositely propagating travelingwave oscillations within said resonator, means for pumping said active medium at a level sufficient to support said oscillations within said active medium, an auxiliary optical ring resonator disposed within said primary ring resonator and coupled to said primary ring resonator by beam splitters oriented to direct out of said apparatus oscillations that are not resonant in both said primary and said auxiliary resonators, feedback means for tuning said primary resonator to stabilize its resonance with respect to the resonances of said auxiliary resonator, said apparatus being characterized, in that, said active medium is an ionized gaseous medium, said pumping means promotes ion drift within said active medium to provide a selected splitting of peak gains for said oppositely propagating oscillations, said splitting being selected to provide a smoothly varying intensity difference of said oppositely propagating oscillations with tuning of said auxiliary resonator, and feedback means responsive to said intensity difference for tuning said auxiliary resonator to stabilize the intensity difference of the oppositely propagating waves.
Claim 3
Dependent Claim
36 words
Apparatus according to claim 1 in which the active medium is a drifting ionized gaseous medium in which the splitting of the peak gains is a substantial portion of the width of the effective gain curve.
Claim 4
Dependent Claim
30 words
Apparatus according to claim 1 in which the active medium is a drifting ionized gaseous medium in which the splitting is greater than about one-fifth of the gain curve width.
Claim 5
Dependent Claim
30 words
Apparatus according to claim 1 in which the active medium is a drifting ionized gaseous medium in which the splitting is greater than the homogeneous linewidth of the active medium.
Claim 6
Dependent Claim
29 words
Apparatus according to claim 1 in which the active medium is a drifting ionized gaseous medium in which the splitting is about twice the homogeneous linewidth of the medium.
Claim 7
Dependent Claim
24 words
Apparatus according to claIm 1 in which the active medium is a drifting ionized argon gas in which the splitting is about 800 MHz.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-21 | 1975-08-23 | 1976-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-21 | 1979-08-23 | 1980-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-21 | 1983-08-23 | 1984-02-22 | $7700.00 | Window Closed / Lapsed |