US3813546A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of making a subtracted image radiographic record
Assignee: ELSCINT IMAGING Inc
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Filing: 1973-02-28
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Granted: 1974-05-28
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Expires: 1993-02-28
Abstract
Abstract Method and apparatus using an electron radiographic system for making a subtracted image record of an object. The method includes the steps of making the first exposure with a first polarity for the field between the electrodes, reversing the polarity and making a second exposure on the same dielectric receptor, and developing the resultant electrostatic image, typically with a contrast material being introduced into the object between the exposures.
Inventors
- 👤 A Proudian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:21
CPC Classifications
A; A61; A61B; A61B6/00; A61B6/48; A61B6/481; A61B6/50; A61B6/504; G; G03; G03G; G03G15/00; G03G15/054; G03G15/0545
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
125 words
A process of making a subtracted image radiographic record of an object with an electron radiographic system having an imaging chamber with spaced electrodes and an ionizable X-ray opaque fluid in the gap between the electrodes, a dielectric receptor at one of said electrodes, and a dc power supply, including steps of: connecting the power supply across the electrodes with a first polarity; making a first exposure to produce an electrostatic image on said receptor; connecting the power supply across the electrodes with the opposite polarity; making a second exposure to produce another electrostatic image on said receptor; and developing the resultant electrostatic image on the receptor which image is a record of changes taking place in the object between the first and second exposures.
Claim 2
Dependent Claim
125 words
A process of making a subtracted image radiographic record of an object with an electron radiographic system having an imaging chamber with spaced electrodes and an ionizable X-ray opaque fluid in the gap between the electrodes, a dielectric receptor at one of said electrodes, and a dc power supply, including steps of: connecting the power supply across the electrodes with a first polarity; making a first exposure to produce an electrostatic image on said receptor; connecting the power supply across the electrodes with the opposite polarity; making a second exposure to produce another electrostatic image on said receptor; and developing the resultant electrostatic image on the receptor which image is a record of changes taking place in the object between the first and second exposures.
Claim 3
Dependent Claim
23 words
The process of claim 1 including the step of introducing a contrast material into the object between said first and second exposure steps.
References Cited (Backward Citations)
US2866903A
Cited
US3057997A
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US3194131A
Cited
US3534383A
Cited
US3484752A
Cited
US3526767A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-27 | 1977-11-26 | 1978-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-27 | 1981-11-26 | 1982-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-27 | 1985-11-26 | 1986-05-28 | $7700.00 | Window Closed / Lapsed |