US3931573A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radiation detector
Assignee: GENERAL MICROWAVE PATENT Corp A DE CORP
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Filing: 1972-05-05
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Granted: 1976-01-06
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Expires: 1992-05-05
Abstract
Abstract A detection device for electromagnetic radiation uses strips of thin resistive films connected in electrically conductive paths with the area of spacing between adjacent ones of the strips being greater than the area of the strips to achieve an impedance which is largely resistive over a broad band of radio frequencies. The strips are mounted in dielectric material and exposed to free space radiation. A radiation hazard meter is produced with thermally sinked thermocouple elements forming the resistive strips.
Inventors
- 👤 Samuel Hopfer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:51
CPC Classifications
G; G01; G01R; G01R5/00; G01R5/22; G01R5/26; G01R29/00; G01R29/08; G01R29/0864; G01R29/0878
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
109 words
An electrical circuit device for detecting free space radio frequency radiation fields, said device including: a plurality of spaced conductive strips in the form of thin resistive films whose thickness is small compared to the skin depth at the radio frequency, said strips being connected in an electrically conductive path, and a non-metallic housing for said strips including means for surrounding said strips with dielectric material for passing said radiation fields to said strips, the area of spacing between adjacent ones of said strips being greater than the area of said strips so that the impedance of said strips is largely resistive over a broad band of radio frequencies.
Claim 2
Dependent Claim
109 words
An electrical circuit device for detecting free space radio frequency radiation fields, said device including: a plurality of spaced conductive strips in the form of thin resistive films whose thickness is small compared to the skin depth at the radio frequency, said strips being connected in an electrically conductive path, and a non-metallic housing for said strips including means for surrounding said strips with dielectric material for passing said radiation fields to said strips, the area of spacing between adjacent ones of said strips being greater than the area of said strips so that the impedance of said strips is largely resistive over a broad band of radio frequencies.
Claim 3
Dependent Claim
27 words
A radiation detecting device as recited in claim 1 wherein said strips have thermal characteristics so that changes in temperature with absorption of radiation can be detected.
Claim 4
Dependent Claim
17 words
A radiation detecting device as recited in claim 2 wherein said strips include thermoelectric materials forming thermocouples.
Claim 5
Dependent Claim
31 words
A radiation detecting device as recited in claim 2 wherein each of said strips includes a plurality of thermocouples connected in series-aiding relation, and said strips are connected in series-aiding relation.
Claim 6
Dependent Claim
43 words
A radiation detecting device as recited in claim 4 wherein a first plurality of said strips are parallel and are arranged to be transverse to a second plurality of said strips to be respectively responsive to two transverse components of an electric field.
Claim 7
Dependent Claim
45 words
A radiation detecting device as recited in claim 5 wherein a third plurality of said strips are parallel and are arranged to be transverse to the strips of said first and second pluralities to be responsive to a third transverse component of an electric field.
Claim 8
Dependent Claim
57 words
A radiation detecting device as recited in claim 5 wherein the strips of said first and second pluralities cross each other at the cold junctions thereof; and further comprising dielectric means having a high thermal conductivity and connected in thermally conductive relation to said cold junctions to provide a substantially uniform reference temperature for said cold junctions.
Claim 9
Dependent Claim
134 words
An electrical circuit device for detecting radio frequency radiation, said device including: a plurality of spaced conductive strips in the form of thin resistive films whose thickness is small compared to the skin depth at the radio frequency, said strips having substantial resistance and being connected in an electrically conductive path, a first group of said strips being parallel and a second group of said strips being parallel and transverse to said first strips to form a grid, the spacing between adjacent ones of said parallel strips being greater than the width of said strips, so that the impedance of said grid of strips to free space radio frequency radiation is largely resistive over a broad band of radio frequencies, and dielectric means for mounting said strips for exposure to free space radiation fields.
Claim 10
Dependent Claim
134 words
An electrical circuit device for detecting radio frequency radiation, said device including: a plurality of spaced conductive strips in the form of thin resistive films whose thickness is small compared to the skin depth at the radio frequency, said strips having substantial resistance and being connected in an electrically conductive path, a first group of said strips being parallel and a second group of said strips being parallel and transverse to said first strips to form a grid, the spacing between adjacent ones of said parallel strips being greater than the width of said strips, so that the impedance of said grid of strips to free space radio frequency radiation is largely resistive over a broad band of radio frequencies, and dielectric means for mounting said strips for exposure to free space radiation fields.
Claim 11
Dependent Claim
46 words
A radiation detecting device as recited in claim 8 wherein the resistance of each of said strips is less than 100 ohms per square, and the equivalent resistance of said grid of strips to free space radio frequency radiation is greater than 300 ohms per square.
Claim 12
Dependent Claim
74 words
A thermoelectric device for radiation detection comprising: a plurality of conductive means forming thermocouples formed of different thin resistive films connected in a sequence of alternatingly different films connected to form a plurality of cold junctions and hot junctions therebetween; and dielectric means spaced from said hot junctions and having a high thermal conductivity and connecting said cold junctions in thermally conductive relation to provide a substantially uniform reference temperature for said cold junctions.
Claim 13
Dependent Claim
74 words
A thermoelectric device for radiation detection comprising: a plurality of conductive means forming thermocouples formed of different thin resistive films connected in a sequence of alternatingly different films connected to form a plurality of cold junctions and hot junctions therebetween; and dielectric means spaced from said hot junctions and having a high thermal conductivity and connecting said cold junctions in thermally conductive relation to provide a substantially uniform reference temperature for said cold junctions.
Claim 14
Dependent Claim
47 words
A radiation detecting device as recited in claim 10 wherein said conductive means includes a thin dielectric planar substrate with said films deposited thereon; said dielectric means includes a block of dielectric material having a plurality of projecting pads for engaging said substrate at said cold junctions.
Claim 15
Dependent Claim
16 words
A radiation detecting device as recited in claim 11 wherein said dielectric material is boron nitride.
Claim 16
Dependent Claim
26 words
A radiation detecting device as recited in claim 10, wherein said dielectric means has a substantial bulk and forms a thermal sink for said cold junctions.
Claim 17
Dependent Claim
133 words
An electrical circuit device for detecting free space radio frequency radiation fields, said device including: a plurality of spaced conductive strips in the form of thin resistive films whose thickness is small compared to the skin depth at the radio frequency, said strips being connected in an electrically conductive path, and a non-metallic housing for said strips including means for surrounding said strips with dielectric material for passing said radiation fields to said strips, said strips being arranged to present a generally resistive impedance substantially greater than that of free space to said radio frequency radiation fields and having a negligible reflective characteristic, said detecting device having the property that, for a value of ohms per square equal to free space, power absorption from free space by said strips is not a maximum.
Claim 18
Dependent Claim
133 words
An electrical circuit device for detecting free space radio frequency radiation fields, said device including: a plurality of spaced conductive strips in the form of thin resistive films whose thickness is small compared to the skin depth at the radio frequency, said strips being connected in an electrically conductive path, and a non-metallic housing for said strips including means for surrounding said strips with dielectric material for passing said radiation fields to said strips, said strips being arranged to present a generally resistive impedance substantially greater than that of free space to said radio frequency radiation fields and having a negligible reflective characteristic, said detecting device having the property that, for a value of ohms per square equal to free space, power absorption from free space by said strips is not a maximum.
Claim 19
Dependent Claim
33 words
A radiation detecting device as recited in claim 14 wherein said transverse strips have a transmission characteristic to transmit at least about half of said radiation field to which said strips are exposed.
Claim 20
Dependent Claim
73 words
A radiation transformer for radiation fields at radio frequencies comprising: a non-metallic housing containing a plurality of spaced resistive strips with the spacing between said strips being large compared to the width of the strips, and means for deriving electrical signals from said strips; said transformer having the property that, for a value of ohms per square equal to free space, power absorption from free space by the transformer is not a maximum.
Claim 21
Dependent Claim
73 words
A radiation transformer for radiation fields at radio frequencies comprising: a non-metallic housing containing a plurality of spaced resistive strips with the spacing between said strips being large compared to the width of the strips, and means for deriving electrical signals from said strips; said transformer having the property that, for a value of ohms per square equal to free space, power absorption from free space by the transformer is not a maximum.
Claim 22
Dependent Claim
45 words
A radiation transformer as recited in claim 16, and further comprising a second plurality of spaced resistive strips having a construction similar to that of the first mentioned plurality of resistive strips and oriented transversely thereto and connected electrically to said first plurality of strips.
Claim 23
Dependent Claim
17 words
A radiation transformer as recited in claim 16, wherein said strips each include a plurality of thermocouples.
Claim 24
Independent Claim
89 words
A device for detecting free space radio frequency radiation, said device comprising: an electrically continuous resistive strip with, separate portions extending in transverse directions over an area and having a largely resistive impedance effective over said area to free space radio frequency radiation and substantially greater than that of free space and having a negligible reflective characteristic, said detecting device having the property that, for a value of ohms per square equal to free space, power absorption from free space by the detecting device is less than a maximum.
Claim 25
Independent Claim
89 words
A device for detecting free space radio frequency radiation, said device comprising: an electrically continuous resistive strip with, separate portions extending in transverse directions over an area and having a largely resistive impedance effective over said area to free space radio frequency radiation and substantially greater than that of free space and having a negligible reflective characteristic, said detecting device having the property that, for a value of ohms per square equal to free space, power absorption from free space by the detecting device is less than a maximum.
Claim 26
Dependent Claim
30 words
A free space radiation detecting device as recited in claim 19, wherein said separate portions extend at substantially right angles corresponding respectively to orthogonal components of the free space radiation.
Claim 27
Dependent Claim
27 words
A device for detecting free space radio frequency radiation as recited in claim 19, wherein said strip includes an additional portion extending transversely to said separate portions.
Claim 28
Dependent Claim
35 words
A device for detecting free space radio frequency radiation, as recited in claim 21, wherein said separate and additional portions respectively extend along three orthogonal axes corresponding respectively to orthogonal components of free space radiation.
Claim 29
Dependent Claim
27 words
A device for detecting free space radio frequency radiation as recited in claim 19, wherein said resistive impedance is a plurality of times that of free space.
Claim 30
Dependent Claim
22 words
A device for detecting free space radio frequency radiation as recited in claim 19, wherein said resistive impedance is about 1,000 ohms.
Claim 31
Dependent Claim
45 words
A device for detecting free space radio frequency radiation as recited in claim 19, and further comprising a dielectric and thermally insulating enclosure for said strip to permit the passage of free space radio frequency radiation and to isolate said strip from external infra-red radiation.
Claim 32
Dependent Claim
27 words
A device for detecting free space radio frequency radiation as recited in claim 19, and further comprising means for connecting said resistive strip in a measuring circuit.
Claim 33
Dependent Claim
30 words
A device for detecting free space radio frequency radiation as recited in claim 19, wherein said resistive strip has electrical characteristics that vary with the amount of radiation absorbed thereby.
Claim 34
Dependent Claim
24 words
A device for detecting free space radio frequency radiation as recited in claim 27, wherein each of said separate strip portions includes a thermocouple.
Claim 35
Dependent Claim
36 words
A device for detecting free space radio frequency radiation as recited in claim 28, wherein each of said separate strip portions includes a plurality of series connected thermocouples extending in the direction of the strip portion.
Claim 36
Dependent Claim
46 words
A device for detecting free space radio frequency radiation as recited in claim 19, wherein said separate strip portions extend along orthogonal sides of a unit square, and the width of said strip is substantially less than the length of a side of said unit square.
Claim 37
Dependent Claim
30 words
A device for detecting free space radio frequency radiation as recited in claim 30, wherein the length of said unit square side is many times the width of said strip.
Claim 38
Dependent Claim
27 words
A radiation detecting device as recited in claim 10, wherein said dielectric means includes a substantially solid member for thermally isolating said thermocouples from external infra-red radiation.
Claim 39
Dependent Claim
32 words
A free space radiation detecting device as recited in claim 32, wherein said dielectric means further includes a second substantially solid member similar to the first-mentioned solid member for enclosing said thermocouples.
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) | 1979-01-05 | 1979-07-07 | 1980-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-05 | 1983-07-07 | 1984-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-05 | 1987-07-07 | 1988-01-06 | $7700.00 | Window Closed / Lapsed |