Patent US4354271A successfully refreshed from Google Patents.
US4354271A
Expired / Lapsed
US
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Frequency-controlled, unstable optical resonator
Assignee: Boeing North American Inc
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Filing: 1980-04-28
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Granted: 1982-10-12
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Expires: 2000-04-28
Abstract
Abstract The lasing action in an unstable optical resonator is controlled as to frequency by limiting frequency selectivity to an axis-near beam. The control is provided preferably outside the cavity by means of active or passive elements. A passive element returns a frequency-controlled beam into the cavity, an active element injects a control beam at the desired frequency.
Inventors
- 👤 John F. Hon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 09:29
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/05; H01S3/08; H01S3/081; H01S3/0818
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
80 words
In an unstable optical resonator, having a concave reflector, a convex reflector facing the concave reflector on a common axis, and a scraper mirror, having an aperture and being traversed by the axis, the improvement of frequency-selective means located outside the optical cavity defined by said reflectors and serving to reflect only radiation of preselected frequency in beams directly on or very nearly on the axis and having an effective aperture significantly smaller than the aperture of the scraper mirror.
Claim 2
Dependent Claim
80 words
In an unstable optical resonator, having a concave reflector, a convex reflector facing the concave reflector on a common axis, and a scraper mirror, having an aperture and being traversed by the axis, the improvement of frequency-selective means located outside the optical cavity defined by said reflectors and serving to reflect only radiation of preselected frequency in beams directly on or very nearly on the axis and having an effective aperture significantly smaller than the aperture of the scraper mirror.
Claim 3
Dependent Claim
19 words
The improvement of claim 1 wherein one of the reflectors is formed with an aperture defining said effective aperture.
Claim 4
Dependent Claim
12 words
The improvement of claim 2, said frequency-selective means being a frequency-selective reflector.
Claim 5
Dependent Claim
16 words
The improvement of claim 2, said frequency-selective means being a reflector combined with a frequency-selective absorber.
Claim 6
Dependent Claim
54 words
The improvement of claim 2, said frequency-selective means being a relatively small frequency-selective laser, injecting a beam of selected frequency or frequencies through said aperture in the one reflector and a cavity defined by said reflectors, said unstable resonator including an active media and a pump source within the environment of said unstable resonator.
Claim 7
Dependent Claim
64 words
In an unstable optical resonator, which includes first and second reflectors, defining a resonator cavity having an axis, and aperture means limiting the width of a beam resonating in the cavity, a frequency-selective means located outside said cavity having an effective aperture much smaller than an aperture as defined by the aperture means, for reflecting only preselected frequencies on or nearly on the axis.
Claim 8
Dependent Claim
64 words
In an unstable optical resonator, which includes first and second reflectors, defining a resonator cavity having an axis, and aperture means limiting the width of a beam resonating in the cavity, a frequency-selective means located outside said cavity having an effective aperture much smaller than an aperture as defined by the aperture means, for reflecting only preselected frequencies on or nearly on the axis.
Claim 9
Dependent Claim
20 words
The improvement as in claim 6, the frequency-selective means being disposed outside the cavity and including a frequency-selective reflecting means.
Claim 10
Dependent Claim
53 words
The improvement as in claim 6, the frequency-selective means being disposed outside the cavity and including laser means for injecting a very narrow beam, having the frequency or frequencies to be selected, into the cavity, said unstable resonator including an active media and a pump source within the environment of said unstable resonator.
Claim 11
Dependent Claim
14 words
The improvement as in claim 6, wherein the frequency-selective means is a frequency-selective absorber.
Claim 12
Dependent Claim
19 words
The improvement as in claim 2 or 6, the effective aperture having a width of about one Fresnel zone.
References Cited (Backward Citations)
US3969685A
Cited
US4019157A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-10-11 | 1986-04-12 | 1986-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-11 | 1990-04-12 | 1990-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-11 | 1994-04-12 | 1994-10-12 | $7700.00 | Window Closed / Lapsed |