US4645934A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for examining a flat radiograph of an object and ionization chamber for performing the process
Assignee: Commissariat à l'Énergie Atomique et Aux Énergies Alternatives
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Filing: 1984-01-03
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Granted: 1987-02-24
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Expires: 2004-01-03
Abstract
Abstract A process for the examination of the flat radiograph of an object irradiated with the aid of an ionizing radiation source is disclosed. In an ionization chamber is detected the latent image of the object formed by the different electrical charges produced in the volume of the chamber under the influence of the impact of the radiation flux which has traversed the object. As this irradiation is continuous, the object to be examined is moved relative to the ionization chamber in the direction and at the migration speed of the ions formed in the electrical field thereof.
Inventors
- 👤 Robert Allemand
- 👤 Jean-Jacques Gagelin
- 👤 Gaetan Pleyber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:16
CPC Classifications
A; A61; A61B; A61B6/00; A61B6/02; H; H01; H01J; H01J47/00; H01J47/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
232 words
A process for the examination of a flat radiograph of an object comprising the steps of providing an ionizing radiation source of the type in which detection on a collecting electrode of the latent image of the object formed takes place in an ionization chamber by the different electrical charges produced in the volume of the chamber under the influence of the impact of the radiation flux which has traversed the object; producing an electrical field between an anode and a cathode at opposite ends of said chamber to establish an ion migration speed; deducing a latent image along X and Y coordinates, with the X coordinate corresponding to the direction of ion migration produced by said electrical field in said chamber and to the displacement direction of the object from the arrival time of the corresponding charge on the collecting electrode, said ion migration being at a substantially constant and continuous speed, and with the perpendicular Y coordinate corresponding to the displacement of the object from the location of impact of the same charge on the collecting electrode; continuously irradiating the object; and moving the object relative to the ionization chamber in the direction of the X coordinate and at a speed equal to the constant and continuous migration speed of the ions formed in the electrical field thereof, to thereby superimpose the different instantaneous latent images into a single image.
Claim 2
Dependent Claim
232 words
A process for the examination of a flat radiograph of an object comprising the steps of providing an ionizing radiation source of the type in which detection on a collecting electrode of the latent image of the object formed takes place in an ionization chamber by the different electrical charges produced in the volume of the chamber under the influence of the impact of the radiation flux which has traversed the object; producing an electrical field between an anode and a cathode at opposite ends of said chamber to establish an ion migration speed; deducing a latent image along X and Y coordinates, with the X coordinate corresponding to the direction of ion migration produced by said electrical field in said chamber and to the displacement direction of the object from the arrival time of the corresponding charge on the collecting electrode, said ion migration being at a substantially constant and continuous speed, and with the perpendicular Y coordinate corresponding to the displacement of the object from the location of impact of the same charge on the collecting electrode; continuously irradiating the object; and moving the object relative to the ionization chamber in the direction of the X coordinate and at a speed equal to the constant and continuous migration speed of the ions formed in the electrical field thereof, to thereby superimpose the different instantaneous latent images into a single image.
References Cited (Backward Citations)
US4047041A
Cited
GB2057184A
Cited
EP0046244A2
Cited
US4392237A
Cited
US4383327A
Cited
US4407040A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-02-23 | 1990-08-25 | 1991-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-23 | 1994-08-25 | 1995-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-23 | 1998-08-25 | 1999-02-24 | $7700.00 | Window Closed / Lapsed |