US3875408A
Expired / Lapsed
US
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Method and device for ascertaining thermal constrasts
Assignee: Individual
•
Filing: 1973-07-09
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Granted: 1975-04-01
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Expires: 1993-07-09
Abstract
Abstract A method of and device for ascertaining thermal constrasts, according to which the reception of thermal radiation is limited to the through passage region of an atmospheric window.
Inventors
- 👤 Gunter Pusch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:02
CPC Classifications
G; G01; G01J; G01J5/00; G01J5/02; G01J5/06; G01J5/061; G01J5/064; G01J5/08; G01J5/0801; G01J5/0802; G01J5/0806; G01J5/0815; G01J5/0846; G01J5/0893
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
66 words
A method of ascertaining thermal contrasts, which includes a. the step of limiting the reception of thermal radiation to the through-passage region of an atmospheric window from 3.0 to 4.2 Mu m wavelength and thereby excluding the disturbing radiation of the absorbing gases (CO2 and H2O) from being received, b. the further step of using a detector whose sensitivity has its maximum in that atmospheric window.
Claim 2
Independent Claim
66 words
A method of ascertaining thermal contrasts, which includes a. the step of limiting the reception of thermal radiation to the through-passage region of an atmospheric window from 3.0 to 4.2 Mu m wavelength and thereby excluding the disturbing radiation of the absorbing gases (CO2 and H2O) from being received, b. the further step of using a detector whose sensitivity has its maximum in that atmospheric window.
Claim 3
Dependent Claim
46 words
An IR-detector system for ascertaining thermal contrasts, which includes means for limiting the reception of thermal radiation to the through-passage region of an atmospheric window from 3.0 to 4.2 Mu m wavelength and a detector having maximum sensitivity in an upper region of said atmospheric window.
Claim 4
Dependent Claim
46 words
An IR-detector system for ascertaining thermal contrasts, which includes means for limiting the reception of thermal radiation to the through-passage region of an atmospheric window from 3.0 to 4.2 Mu m wavelength and a detector having maximum sensitivity in an upper region of said atmospheric window.
Claim 5
Dependent Claim
47 words
A detector system according to claim 2, in which the composition of the material of said detector is such that the drop of the sensitivity of said detector at the 4.2-side of said window follows approximately the same steepness as the through passage curve of said window.
Claim 6
Dependent Claim
15 words
A detector system according to claim 2, in which the detector material is substantially CdHg:HgTe.
Claim 7
Dependent Claim
45 words
A detector system according to claim 2, which includes an optical filter arranged in front of said detector and being transpareNt only in said atmospheric window, said filter having a drop characteristic which approximately equals the drop characteristic at the 4.2-side of said atmospheric window.
Claim 8
Dependent Claim
33 words
A detector system according to claim 5, in which said optical filter is designed as reflection filter and outside said atmospheric window has a mirroring reflection in the direction of said detector system.
Claim 9
Dependent Claim
29 words
A detector system according to claim 5, in which said optical filter is spherical, and in which said detector is located at the spherical center of said optical filter.
Claim 10
Dependent Claim
27 words
A detector system according to claim 2, which includes a spherical mirroring apertured diaphragm, and in which said detector is located in the center of said diaphragm.
Claim 11
Dependent Claim
31 words
A detector system according to claim 2, which includes a spherical reflection filter, and a spherical mirroring apertured diaphragm, said reflection filter being coaxially arranged in the aperture of said diaphragm.
Claim 12
Dependent Claim
58 words
A detector system according to claim 2, which includes a spherical optical filter and a spherical mirroring apertured diaphragm, and in which the detector is a series detector adjusted symmetrically with regard to the spherical center of said mirroring apertured diaphragm so that detector elements located in the blocking range of said mirroring apertured diaphragm mirror each other.
Claim 13
Dependent Claim
34 words
A detector system according to claim 10, which includes a pinhole diaphragm, and in which in the through-passage region of said filter the detector elements mirror each other by means of said pinhole diaphragm.
Claim 14
Dependent Claim
22 words
A detector system according to claim 11, in which the mirror arrangement is such that the image of said detector is unsharp.
Claim 15
Dependent Claim
38 words
A detector system according to claim 12, which includes surface means having said detector arranged thereon, and which includes cooling means for cooling said surface means, said unsharp image of said detector not exceeding said cooled surface means.
Claim 16
Dependent Claim
20 words
A detector system according to claim 13, in which the cooling means for cooling said detector are thermo-electric cooling means.
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) | 1978-03-31 | 1978-09-30 | 1979-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-31 | 1982-09-30 | 1983-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-31 | 1986-09-30 | 1987-04-01 | $7700.00 | Window Closed / Lapsed |