US4227082A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detector for detecting ionizing radiation
Assignee: Thales SA
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Filing: 1978-07-25
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Granted: 1980-10-07
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Expires: 1998-07-25
Abstract
Abstract The detector comprises at least one plate of an electrooptical material having good photoconduction properties and high absorption of X- or γ-rays, preferably materials comprising bismuth oxide. The plate is placed between two electrodes connected to an electric generator through a resistor. A polarized luminous beam passes through the plate. Under the action of the radiation, the conductivity of the plate varies and produces a modification of the polarization state of the luminous beam. This modification is analysed and then detected. In this way there is obtained an indication of the radiation dose received for a given period.
Inventors
- 👤 Christian Mayeux
- 👤 Francois Micheron
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:11
CPC Classifications
G; G01; G01T; G01T1/00; G01T1/16; G01T1/29; G01T1/2914; G01T1/2921
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
159 words
A detector for detecting ionizing radiation, comprising at least one point detecting unit, said unit comprising a plate of an electro-optical material arranged to receive an homogeneous beam of said radiation, said plate being capable of absorbing the most part of said radiation, the resistivity of said material being variable with respect to the intensity of said most part; said unit further comprising two electrodes arranged on opposite faces of said plate parallel to said beam of radiation and forming a capacitor; said detector further comprising electrical means supplying a constant current between said two electrodes, the voltage between said two electrodes being dependent upon the resistivity of said material and creating an electrical birefringence in said plate; said detector further comprising optical means for emitting a luminous beam of polarized light in the direction of said plate, polarization analysing means receiving the light emerging from said plate, and photodetecting means receiving the light transmitted by said analysing means.
Claim 2
Dependent Claim
159 words
A detector for detecting ionizing radiation, comprising at least one point detecting unit, said unit comprising a plate of an electro-optical material arranged to receive an homogeneous beam of said radiation, said plate being capable of absorbing the most part of said radiation, the resistivity of said material being variable with respect to the intensity of said most part; said unit further comprising two electrodes arranged on opposite faces of said plate parallel to said beam of radiation and forming a capacitor; said detector further comprising electrical means supplying a constant current between said two electrodes, the voltage between said two electrodes being dependent upon the resistivity of said material and creating an electrical birefringence in said plate; said detector further comprising optical means for emitting a luminous beam of polarized light in the direction of said plate, polarization analysing means receiving the light emerging from said plate, and photodetecting means receiving the light transmitted by said analysing means.
Claim 3
Dependent Claim
22 words
A detector as claimed in claim 1, wherein said luminous beam passes through the plate in the direction parallel to the electrodes.
Claim 4
Dependent Claim
35 words
A detector as claimed in claim 1, wherein said luminous beam passes through the plate in a direction perpendicular to the electrodes, at least one of the electrodes being transparent in respect of said beam.
Claim 5
Dependent Claim
47 words
A detector as claimed in claim 3, further comprising reflecting means placed on the path of said luminous beam after a first passage through the plate, said luminous beam being reflected by said reflecting means and passing again through said plate in the opposite direction after reflection.
Claim 6
Dependent Claim
19 words
A detector as claimed in claim 4, wherein said reflecting means are constituted by the second of the electrodes.
Claim 7
Dependent Claim
36 words
A detector as claimed in claim 1, wherein said electrical means comprise switching means for periodically returning the voltage between the electrodes to a magnitude equal to the equilibrium voltage existing when there is no radiation.
Claim 8
Dependent Claim
13 words
A detector as claimed in claim 1, wherein said material is bismuth oxide.
Claim 9
Dependent Claim
15 words
A detector as claimed in claim 1, wherein said material is bismuth and silicon oxide.
Claim 10
Dependent Claim
15 words
A detector as claimed in claim 1, wherein said material is bismuth and germanium oxide.
Claim 11
Dependent Claim
13 words
A detector as claimed in claim 1, wherein said luminous beam is monochromatic.
Claim 12
Dependent Claim
43 words
A detector as claimed in claim 1, comprising n units and wherein said optical means comprise a source of a first polarized luminous beam and semireflecting plates dividing said first beam between n secondary beams respectively transmitted the plates of said n units.
Claim 13
Dependent Claim
19 words
A detector as claimed in claim 1, comprising n units and wherein said optical means comprise n luminous sources.
Claim 14
Independent Claim
228 words
A device for examining an object, said object being non transparent in respect of ionizing radiation, said device comprising a. a source of ionizing radiation, a detector for detecting ionizing radiation, comprising at least one point detecting unit, said unit comprising a plate of an electro-optical material arranged to receive an homogeneous beam of said radiation, said plate being capable of absorbing the most part of said radiation, the resistivity of said material being variable with respect to the intensity of said most part; said unit further comprising two electrodes arranged on opposite faces of said plate parallel to said beam of radiation and forming a capacitor; said detector further comprising electrical means supplying a constant current between said two electrodes, the voltage between said two electrodes being dependent upon the resistivity of said material and creating an electrical birefringence in said plate; said detector further comprising optical means for emitting a luminous beam of polarized light in the direction of said plate, polarization analysing means receiving the light emerging from said plate, and photodetecting means receiving the light transmitted by said analysing means, c. shifting means mechanically connected to said source of ionizing radiation and said detector, said detector receiving the part of radiation transmitted by said object and providing data relative to the absorption of said radiation by said object in a plurality of rectilinear paths.
Claim 15
Independent Claim
228 words
A device for examining an object, said object being non transparent in respect of ionizing radiation, said device comprising a. a source of ionizing radiation, a detector for detecting ionizing radiation, comprising at least one point detecting unit, said unit comprising a plate of an electro-optical material arranged to receive an homogeneous beam of said radiation, said plate being capable of absorbing the most part of said radiation, the resistivity of said material being variable with respect to the intensity of said most part; said unit further comprising two electrodes arranged on opposite faces of said plate parallel to said beam of radiation and forming a capacitor; said detector further comprising electrical means supplying a constant current between said two electrodes, the voltage between said two electrodes being dependent upon the resistivity of said material and creating an electrical birefringence in said plate; said detector further comprising optical means for emitting a luminous beam of polarized light in the direction of said plate, polarization analysing means receiving the light emerging from said plate, and photodetecting means receiving the light transmitted by said analysing means, c. shifting means mechanically connected to said source of ionizing radiation and said detector, said detector receiving the part of radiation transmitted by said object and providing data relative to the absorption of said radiation by said object in a plurality of rectilinear paths.
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) | 1983-10-07 | 1984-04-07 | 1984-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-07 | 1988-04-07 | 1988-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-07 | 1992-04-07 | 1992-10-07 | $7700.00 | Window Closed / Lapsed |