Patent US3744423A successfully refreshed from Google Patents.
US3744423A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gaseous optical filter
Assignee: United States Department of the Navy
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Filing: 1961-12-27
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Granted: 1973-07-10
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Expires: 1981-12-27
Abstract
Abstract 1. An optical filter for discrimination purposes in the infrared region comprising a casing containing an infrared absorbing gas which is effective to produce an extremely sharp absorption cutoff point when infrared radiation having wavelengths within a predetermined range is applied thereto thereby is effective to pass infrared radiation of wavelengths outside of said range, said casing having a circular configuration for close fitting engagement with a complementary aperture within the nose of a proximity fuze.
Inventors
- 👤 E Ertsgaard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:00
CPC Classifications
F; F42; F42C; F42C19/00; G; G02; G02B; G02B5/00; G02B5/20; G02B5/202
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
72 words
An optical filter for discrimination purposes in the infrared region compressing a casing containing an infrared absorbing gas which is effective to produce an extremely sharp absorption cutoff point when infrared radiation having wavelengths within a predetermined range is applied thereto to thereby pass infrared radiation of wavelengths outside of said range, said casing having a circular configuration for close fitting engagement with a complementary aperture within the nose of proximity fuze.
Claim 2
Dependent Claim
72 words
An optical filter for discrimination purposes in the infrared region compressing a casing containing an infrared absorbing gas which is effective to produce an extremely sharp absorption cutoff point when infrared radiation having wavelengths within a predetermined range is applied thereto to thereby pass infrared radiation of wavelengths outside of said range, said casing having a circular configuration for close fitting engagement with a complementary aperture within the nose of proximity fuze.
Claim 3
Dependent Claim
11 words
The apparatus of claim 1 wherein the gas is nitrous oxide.
Claim 4
Dependent Claim
11 words
The apparatus of claim 1 wherein the gas is aluminum borohyride.
Claim 5
Dependent Claim
11 words
The apparatus of claim 1 wherein the gas is carbon dioxide.
Claim 6
Dependent Claim
26 words
The apparatus of claim 1 having means to vary the pressure oF said gas whereby said absorption cut-off point may be shifted to different infrared wavelengths.
Claim 7
Dependent Claim
25 words
The apparatus of claim 1 having means to add impurities to said gas whereby said absorption cut-off point may be shifted to different infrared wavelengths.
Claim 8
Dependent Claim
130 words
A gaseous optical filter for solar discrimination purposes in the infrared region comprising a hollow closed cylindrical body portion having an aperture therein and containing a gas under pressure which will pass infrared radiation with a predetermined range of frequencies, a source of variable pressure, a source of impurities, and three-wave valve means connected to said body portion at the aperture and to said variable pressure and impurities sources to selectively establish a fluid connection therefrom to the aperture in a manner to provide for a variation in the pressure of said gas within said body and for the adding of certain impurities of said gas, the valve also providing means for effectively sealing said aperture when a desired pressure and quantity of impurities within the body have been obtained.
Claim 9
Dependent Claim
130 words
A gaseous optical filter for solar discrimination purposes in the infrared region comprising a hollow closed cylindrical body portion having an aperture therein and containing a gas under pressure which will pass infrared radiation with a predetermined range of frequencies, a source of variable pressure, a source of impurities, and three-wave valve means connected to said body portion at the aperture and to said variable pressure and impurities sources to selectively establish a fluid connection therefrom to the aperture in a manner to provide for a variation in the pressure of said gas within said body and for the adding of certain impurities of said gas, the valve also providing means for effectively sealing said aperture when a desired pressure and quantity of impurities within the body have been obtained.
Claim 10
Dependent Claim
12 words
The apparatus of claim 7 wherein the absorbing gas is nitrous oxide.
Claim 11
Dependent Claim
12 words
The apparatus of claim 7 wherein the absorbing gas is aluminum borohydride.
Claim 12
Dependent Claim
12 words
The apparatus of claim 7 wherein the absorbing gas is carbon dioxide.
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) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |