US4027160A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Infrared detection system with parallel strip reticle means
Assignee: United States Department of the Army
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Filing: 1971-05-18
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Granted: 1977-05-31
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Expires: 1991-05-18
Abstract
Abstract Optical detectors are arranged along the focal length of a spherical mirr Signals passed by a lens and reflected by the mirror impinge on the detectors as the system scans the horizon. A reticle means is placed between the mirror and the detector to cause the optical system to discriminate against large radiating areas in the field of view of the lens. The reticle means may be straight or zig-zag opaque lines. The cross-sectional area of the lines and the area therebetween is such that radiation from point sources will impinge the detector in only one area at a time while radiation from large sources will overlap a plurality of areas. The output frequency from the detectors is indicative of the type of the radiation source.
Inventors
- 👤 John B. Driffield
- 👤 Howard S. Kerr
- 👤 Richard M. Penrose
- 👤 Anthony C. Stonell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:44
CPC Classifications
H; H10; H10F; H10F77/00; H10F77/30; H10F77/306; H10F77/331; H10F77/334; G; G01; G01S; G01S3/00; G01S3/78; G01S3/781; G01S3/782; G01S3/789; G02; G02B; G02B23/00; G02B23/12
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
165 words
An optical system for infrared detection comprising: a viewing lens; a mirror having a focal length, said mirror being positioned to receive the light passed by said viewing lens; a plurality of detector cells positioned to lie in the focal length of said mirror; reticle means positioned on said detector cells whereby said optical system differentiates between infrared radiation from large sources and point sources, wherein said mirror is a spherical mirror having an overcoat of silicon monoxide thereby providing maximum reflectivity in the wavelength region of 3 to 5 microns, wherein said viewing lens is an aspheric corrector shaped to correct said optical system for spherical aberration, said lens comprising optical silicon having a cut-on wavelength of approximately one micron thereby excluding radiation of less than one micron from said optical system, and wherein said reticle means is positioned between said mirror and said detector cells, said reticle means comprising a sapphire substrate having a reticle of parallel strips of an opaque material thereon.
Claim 2
Dependent Claim
165 words
An optical system for infrared detection comprising: a viewing lens; a mirror having a focal length, said mirror being positioned to receive the light passed by said viewing lens; a plurality of detector cells positioned to lie in the focal length of said mirror; reticle means positioned on said detector cells whereby said optical system differentiates between infrared radiation from large sources and point sources, wherein said mirror is a spherical mirror having an overcoat of silicon monoxide thereby providing maximum reflectivity in the wavelength region of 3 to 5 microns, wherein said viewing lens is an aspheric corrector shaped to correct said optical system for spherical aberration, said lens comprising optical silicon having a cut-on wavelength of approximately one micron thereby excluding radiation of less than one micron from said optical system, and wherein said reticle means is positioned between said mirror and said detector cells, said reticle means comprising a sapphire substrate having a reticle of parallel strips of an opaque material thereon.
Claim 3
Dependent Claim
33 words
An optical system as set forth in claim 1 wherein said strips of said opaque material are zig-zags whereby said optical system discriminates between point sources of emission and narrow, vertical band emission.
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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) | 1980-05-30 | 1980-11-29 | 1981-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-30 | 1984-11-29 | 1985-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-30 | 1988-11-29 | 1989-05-31 | $7700.00 | Window Closed / Lapsed |