US3856988A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Scanning optical imaging system with real-time image thresholding for the elimination of backscattered light
Assignee: United States Department of the Navy
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Filing: 1973-08-24
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Granted: 1974-12-24
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Expires: 1993-08-24
Abstract
Abstract An imaging system is provided for environments where light scattering reduces image quality. The imaging system comprises a scanning illumination source to illuminate an object field. A first photoelectric transducer converts a focused image of the illuminated object field to an electric analog. A second realtime thresholding photoelectric transducer is physically and electrically connected to the first transducer to recreate an optical image of the object field having electrical analog values in excess of a predetermined value. Utilization of the optical output from the second transducer is by conventional optical or electro-optical systems.
Inventors
- 👤 C Funk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 01:03
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/30
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
145 words
A light modulation system to recreate an image field comprising: illuminating means for illumination of a field object zone; optical imaging means for providing an image of said field object zone; first photoelectric transducer means positioned with respect to said optical imaging means to receive the image produced thereby for producing electrical analog signal of the image; threshold means connected to said transducer means having a plurality of discreet areas for independently responding to electrical analog signal components having predetermined intensity characteristics; optical transducer means connected to said threshold means and positioned to create an optical analog of thE signals to which said threshold means has responded for recreating an optical image of only a predetermined portion of the original image; and viewing means positioned with respect to said second photoelectric transducer means for utilizing the optical image recreated by said second photoelectric transducer means.
Claim 2
Dependent Claim
145 words
A light modulation system to recreate an image field comprising: illuminating means for illumination of a field object zone; optical imaging means for providing an image of said field object zone; first photoelectric transducer means positioned with respect to said optical imaging means to receive the image produced thereby for producing electrical analog signal of the image; threshold means connected to said transducer means having a plurality of discreet areas for independently responding to electrical analog signal components having predetermined intensity characteristics; optical transducer means connected to said threshold means and positioned to create an optical analog of thE signals to which said threshold means has responded for recreating an optical image of only a predetermined portion of the original image; and viewing means positioned with respect to said second photoelectric transducer means for utilizing the optical image recreated by said second photoelectric transducer means.
Claim 3
Dependent Claim
20 words
A light modulation system according to claim 1 in which said first photoelectric transducer means is a photoconducting type transducer.
Claim 4
Dependent Claim
27 words
A light modulation system according to claim 1 in which said threshold means includes a liquid crystal in physical and electrical contact with said first photoelectric transducer.
Claim 5
Dependent Claim
73 words
A light modulation system according to claim 1 in which said optical transducer means includes a retro-reflective optical illumination system having a light source and image forming means and being optically positioned to illuminate said threshold means and to return light reflected from non-responsive areas thereof to the light source while returning light reflected from responsive areas to the image forming means to provide an optical output signal from the optical transducer means.
Claim 6
Dependent Claim
35 words
A light modulation system according to claim 1 in which said illuminating means includes a scanning source of light which traverses the field object zone in a predetermined time period with narrow beam of light.
Claim 7
Dependent Claim
20 words
A light modulation system according to claim 5 in which said narrow beam of light is a coherent energy beam.
Claim 8
Dependent Claim
20 words
A light modulation system according to claim 6 in which said first photoelectric transducer means is a photoconducting type transducer.
Claim 9
Dependent Claim
27 words
A light modulation system according to claim 7 in which said threshold means includes a liquid crystal in physical and electrical contact with said first photo-electric transducer.
Claim 10
Dependent Claim
73 words
A light modulation system according to claim 8 in which said optical transducer means includes a retroflective optical illumination system having a light source and image forming means and being optically positioned to illuminate said threshold means and to return light reflected from non-responsive areas thereof to the light source while returning light reflected from responsive areas to the image forming means to provide an optical output signal from the optical transducer means.
Claim 11
Dependent Claim
63 words
A light modulation system according to claim 9 in which the aforesaid viewing means includes a closed circuit television system including a camera which is physically and optically positioned to receive the optical output signal from the optical transducer means, whereby an image is transmitted therefrom which corresponds to the portions of the aforesaid field object image having the predetermined image intensity characteristics.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |