Patent US4598408A successfully refreshed from Google Patents.
US4598408A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High extraction efficiency cylindrical ring resonator
Assignee: Northrop Grumman Corp
•
Filing: 1984-10-22
•
Granted: 1986-07-01
•
Expires: 2004-10-22
Abstract
Abstract An annular ring resonator for a high-energy laser, including a waxicon/reflaxicon pair and a conical rear mirror, which combine to provide high energy extraction efficiency, reduced sensitivity to alignment errors, and no polarization state mixing. A cylindrical beam returned from a scraper mirror is first expanded by the waxicon to an annular beam that makes a first pass through a gain region of the laser. The annular beam impinges on the conical mirror and is reflected as an annular beam, to make a second pass of the gain region before encountering the reflaxicon, which compacts the beam for transmission to the scraper mirror. One embodiment employs a double-cone rear mirror, and another employs a single conical surface. The structure may also employ feedback decentering.
Inventors
- 👤 John D. O'Keefe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 01:06
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/05; H01S3/08; H01S3/08059; H01S3/08068; G; G02; G02B; G02B5/00; G02B5/001; H01S3/081; H01S3/083; H01S3/08081; H01S3/0813
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
161 words
An annular ring resonator for a high-energy laser, having high extraction efficiency, and comprising: a conical rear mirror; a scraper mmirror; a first axicon positioned to receive a generally cylindrical beam from the scraper mirror, and to produce an expanded annular beam to pass through an annular gain region to the conical rear mirror; a second axicon, in opposing position to the first axicon, for receiving an annular beam reflected from the conical rear mirror, and producing a generally cylindrical compacted beam for transmission to the scraper mirror, wherein the scraper mirror has an aperture to pass a return beam for transmission to the first axicon; and optical means for transmitting the compacted beam from the second axicon to the scraper mirror and from the scraper mirror to the first axicon; whereby the annular beam makes two passes through the gain region, and the combination of two types of axicons and the conical mirror has substantially no net effect on polarization.
Claim 2
Dependent Claim
161 words
An annular ring resonator for a high-energy laser, having high extraction efficiency, and comprising: a conical rear mirror; a scraper mmirror; a first axicon positioned to receive a generally cylindrical beam from the scraper mirror, and to produce an expanded annular beam to pass through an annular gain region to the conical rear mirror; a second axicon, in opposing position to the first axicon, for receiving an annular beam reflected from the conical rear mirror, and producing a generally cylindrical compacted beam for transmission to the scraper mirror, wherein the scraper mirror has an aperture to pass a return beam for transmission to the first axicon; and optical means for transmitting the compacted beam from the second axicon to the scraper mirror and from the scraper mirror to the first axicon; whereby the annular beam makes two passes through the gain region, and the combination of two types of axicons and the conical mirror has substantially no net effect on polarization.
Claim 3
Dependent Claim
22 words
A resonator as set forth in claim 1 wherein: the first axicon is a waxicon; and the second axicon is a reflaxicon.
Claim 4
Dependent Claim
82 words
A resonator as set forth in claim 2 wherein: the conical rear mirror has an outer segment and a contiguous inner segment, each segment having a different conical apex angle; the annular beam reflected from the waxicon impinges first on the inner segment of the conical mirror and is directed to the outer segment; and the annular beam reflected from the outer segment of the conical rear mirror is concentric with the annular beam in the opposite direction, but of greater diameter.
Claim 5
Dependent Claim
19 words
A resonator as set forth in claim 3 wherein: the waxicon and reflaxicon share a common outer mirror surface.
Claim 6
Dependent Claim
25 words
A resonator as set forth in claim 3 wherein: the scraper mirror has its aperture decentered, to provide a decentered optical axis for the resonator.
Claim 7
Dependent Claim
76 words
A resonator as set forth in claim 2 wherein: the conical rear mirror is a single conical surface; and the annular beam reflected from the waxicon impinges on the conical mirror and is first reflected diametrically across the conical mirror and then from the latter mirror back toward the reflaxicon; and the annular beam reflected from the conical mirror partially overlaps the annular beam directed toward the conical mirror, in the gain region of the laser.
Claim 8
Dependent Claim
25 words
A resonator as set forth in claim 6 wherein: the scraper mirror has its aperture decentered, to provide a decentered optical axis for the resonator.
Claim 9
Dependent Claim
25 words
A resonator as set forth in claim 2 wherein: the scraper mirror has its aperture decentered, to provide a decentered optical axis for the resonator.
Claim 10
Dependent Claim
25 words
A resonator as set forth in claim 1 wherein: the scraper mirror has its aperture decentered, to provide a decentered optical axis for the resonator.
Claim 11
Dependent Claim
24 words
A resonator as set forth in claim 1 wherein: said optical means includes a plurality of flat mirrors for appropriately turning the compact beam.
References Cited (Backward Citations)
US4514850A
Cited
US4516244A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-06-30 | 1989-12-30 | 1990-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-30 | 1993-12-30 | 1994-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-30 | 1997-12-30 | 1998-07-01 | $7700.00 | Window Closed / Lapsed |