US3748484A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Object identification by emission polarization
Assignee: Texas Instruments Inc
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Filing: 1971-06-07
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Granted: 1973-07-24
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Expires: 1991-06-07
Abstract
Abstract Metallic objects are identifiable by the degree of polarization of infrared radiation emitted therefrom. To identify a metallic object from a nonmetallic object by radiation emitted therefrom, three linearly polarized detectors are positioned to be responsive to the emitted radiation. Each of these three detectors is responsive to radiation from the object along a different plane of polarization. Output signals from the three detectors are processed in a system to produce a signal equal to the square of the degree of polarization. Smooth objects are distinguishable from rough objects in the same field of view by determining the degree of polarization of a light beam directed to and reflected from the objects. By knowing the polarization axis of the light waves at the source, the output signals of two detectors may be combined to highlight in a display smooth objects in a field of view that contains both smooth and rough objects.
Inventors
- 👤 D Covault
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:36
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/48; G01S7/499; G01N; G01N21/00; G01N21/17; G01N21/21
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
125 words
The method of identifying an object by determining the degree of polarization of energy reflected therefrom, comprising the steps of: illuminating the object with radiant energy polarized along a known axis, measuring the radiation reflected from said object by polarized detectors orientated at different angles with respect to the known polarized axis, summing the reflected energy measurements as resulting from each of said detectors to obtain a total intensity measurement, generating a signal representing the difference between the total intensity measurements in excess of a threshold value, and summing the total intensity measurement and the signal representing the difference between the intensity measurements above the threshold to produce a display signal that identifies an object by the degree of polarization of the energy reflected therefrom.
Claim 2
Independent Claim
125 words
The method of identifying an object by determining the degree of polarization of energy reflected therefrom, comprising the steps of: illuminating the object with radiant energy polarized along a known axis, measuring the radiation reflected from said object by polarized detectors orientated at different angles with respect to the known polarized axis, summing the reflected energy measurements as resulting from each of said detectors to obtain a total intensity measurement, generating a signal representing the difference between the total intensity measurements in excess of a threshold value, and summing the total intensity measurement and the signal representing the difference between the intensity measurements above the threshold to produce a display signal that identifies an object by the degree of polarization of the energy reflected therefrom.
Claim 3
Dependent Claim
50 words
The method of identifying an object by determining the degree of polarization of energy reflected therefrom as set forth in claim 1 including the step of scanning a field of view with the polarixed energy illuminating the object to generate background display signals used in the identification of an object.
Claim 4
Dependent Claim
46 words
The method of identifying an object by determining the degree of polarization of energy reflected therefrom as set forth in claim 1 including the step of splitting the energy reflected from the object to be identified into a beam for each detector measuring the reflected energy.
Claim 5
Dependent Claim
39 words
The method of identifying an object by determining the degree of polarization of energy reflected therefrom as set forth in claim 1 including the step of inputting said display signal that identifies an object to a cathode ray tube.
Claim 6
Dependent Claim
153 words
Apparatus for identifying an object by determining the degre of polarization of energy reflected therefrom, comprising: means for illuminating a target with energy polarized along a known axis, means for scanning a field of view including the object to be identified with the energy polarized along the known axis, means for measuring the polarized reflected radiation from the scanned area by at least two detectors orientated at different angles with respect to the known axis of the polarized energy, means for summing the reflected energy measurements resulting from each of the detectors to obtain a total intensity measurement, means for generating a signal representing the difference between the intensity measurements from each of the several detectors in excess of a threshold, and means for adding the total intensity measurement signal and the signal in excess of the threshold to produce a display signal for identifying an object in the scanned field of view.
Claim 7
Dependent Claim
153 words
Apparatus for identifying an object by determining the degre of polarization of energy reflected therefrom, comprising: means for illuminating a target with energy polarized along a known axis, means for scanning a field of view including the object to be identified with the energy polarized along the known axis, means for measuring the polarized reflected radiation from the scanned area by at least two detectors orientated at different angles with respect to the known axis of the polarized energy, means for summing the reflected energy measurements resulting from each of the detectors to obtain a total intensity measurement, means for generating a signal representing the difference between the intensity measurements from each of the several detectors in excess of a threshold, and means for adding the total intensity measurement signal and the signal in excess of the threshold to produce a display signal for identifying an object in the scanned field of view.
Claim 8
Dependent Claim
31 words
Appraratus for identifying an object by the degree of polarization of energy reflected therefrom as set forth in claim 5 wherein said illuminating means in a source of monochromatic polarized light.
Claim 9
Dependent Claim
26 words
Apparatus for identifying an object by the degrEe of polarization of energy reflected therefrom as set forth in claim 6 wherein said source is modymium laser.
Claim 10
Dependent Claim
33 words
Apparatus for identifying an object by the degree of polarization of energy reflected therefrom as set forth in claim 5 including means for splitting the reflected radiation into a beam for each detector.
Claim 11
Dependent Claim
27 words
Apparatus for identifying an object by the degree of polarization of energy reflected therefrom as set forth in claim 5 wherein said detectors are silicon photo diodes.
Claim 12
Dependent Claim
39 words
Apparatus for identifying an object by the degree of polarization of energy reflected therefrom as set forth in claim 5 including display means responsive to said display signals and including a cathode ray tube for displaying the area viewed.
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) | 1976-07-23 | 1977-01-22 | 1977-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-23 | 1981-01-22 | 1981-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-23 | 1985-01-22 | 1985-07-24 | $7700.00 | Window Closed / Lapsed |