Patent US4597639A successfully refreshed from Google Patents.
US4597639A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dielectric air-interface plasma optical power limiter
Assignee: United States Department of the Navy
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Filing: 1984-05-07
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Granted: 1986-07-01
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Expires: 2004-05-07
Abstract
Abstract Optical devices which reduce the risk of damage by high energy laser pulsesre made by applying particles to the surface of optical components. The particles serve as plasma initiation sites. The particles are made of material capable of producing large numbers of free electrons when illuminated above a preselected power level. Above the preselected power level, transmittance or reflectance of the optical component is limited by the plasma created by the free electrons.
Inventors
- 👤 Steven C. Seitel
- 👤 C. Denton Marrs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:23
CPC Classifications
B; B23; B23K; B23K26/00; B23K26/02; B23K26/06; B23K26/064; B23K26/0643; C; C23; C23C; C23C14/00; C23C14/04; C23C16/00; C23C16/04; C23C30/00; G; G02; G02B; G02B1/00; G02B1/10; G02B1/14
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
64 words
A device for limiting laser energy or power transmittal comprising: a dielectric plate in the path of received laser energy, one surface of said dielectric plate being exposed to the atmosphere; and a plurality of plasma initiation sites applied to said exposed surface, said sites being particles chosen from the group consisting of sodium fluoride, lead fluoride, lanthanum hexaboride, silicon, or any combination thereof.
Claim 2
Independent Claim
64 words
A device for limiting laser energy or power transmittal comprising: a dielectric plate in the path of received laser energy, one surface of said dielectric plate being exposed to the atmosphere; and a plurality of plasma initiation sites applied to said exposed surface, said sites being particles chosen from the group consisting of sodium fluoride, lead fluoride, lanthanum hexaboride, silicon, or any combination thereof.
Claim 3
Independent Claim
61 words
A device for limiting laser energy or power reflectance comprising: a mirror surface in the path of received laser energy, said mirror surface being exposed to the atmosphere; and a plurality of plasma initiation sites applied to said mirror surface, said sites being particles chosen from the group consisting of sodium fluoride, lead fluoride, silicon, lanthanum hexaboride, or any combination thereof.
Claim 4
Independent Claim
61 words
A device for limiting laser energy or power reflectance comprising: a mirror surface in the path of received laser energy, said mirror surface being exposed to the atmosphere; and a plurality of plasma initiation sites applied to said mirror surface, said sites being particles chosen from the group consisting of sodium fluoride, lead fluoride, silicon, lanthanum hexaboride, or any combination thereof.
Claim 5
Dependent Claim
52 words
An optical radiation attenuating device comprising: an optical component having an exterior surface disposed for inpingment of such radiation; and a plurality of particles disposed on said surface in speckled relation, said particles being of a material which emits electrons when the power of such radiation is above an optical breakdown threshold.
Claim 6
Dependent Claim
52 words
An optical radiation attenuating device comprising: an optical component having an exterior surface disposed for inpingment of such radiation; and a plurality of particles disposed on said surface in speckled relation, said particles being of a material which emits electrons when the power of such radiation is above an optical breakdown threshold.
Claim 7
Dependent Claim
19 words
The device of claim 3 wherein most of the area of said surface is not covered by said particles.
Claim 8
Dependent Claim
32 words
The device of claim 3 further comprising gaseous means interfacing said surface and said particles for ionization by said electrons to generate a plasma which attenuates such radiation impinging on said surface.
Claim 9
Dependent Claim
16 words
The device of claim 3 wherein said optical component transmits such radiation impinging on said surface.
Claim 10
Dependent Claim
15 words
The device of claim 3 wherein such radiation impinging on said surface is reflected therefrom.
Claim 11
Dependent Claim
26 words
The device of claim 3 wherein said material is chosen from the group consisting of sodium fluoride, lead fluoride, lanthanum hexaboride, silicon, or any combination thereof.
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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 |