Patent US4629919A successfully refreshed from Google Patents.
US4199684A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the determination of the electron density in a part volume
Assignee: SCADERA AS
•
Filing: 1978-06-12
•
Granted: 1980-04-22
•
Expires: 1998-06-12
Abstract
Abstract The present invention relates to a method for the determination of the electron density in a part volume in a patient by means of an X-ray tube, said tube comprising an anode symmetrical with respect to rotation as an electron beam rotates relative to the axis of rotation. As a result an X-ray emission from several points is obtained. By means of the scattered X-rays the electron densities can be measured.
Inventors
- 👤 Ib Leunbach
- 👤 Kim Demandt
- 👤 Ottar Skilbreid
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:30
CPC Classifications
G; G21; G21K; G21K1/00; G21K1/02; G21K1/025; H; H01; H01J; H01J35/00; H01J35/02; H01J35/04; H01J35/08; H01J35/112; H01J35/116; H01J35/14; H01J35/153; H01J35/24; H01J35/30
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
138 words
An X-ray tube for use in determining the electron density in a part volume from the scattering of X-rays received from several directions, said X-ray tube comprising a cathode, an anode which is symmetrical with respect to rotation about a predetermined axis and is positioned to receive a beam of electrons from said cathode, and means for causing the electron beam both to scan the anode in a radial direction with respect to said axis and to rotate about said axis, and wherein said anode is formed in the radial direction with steps, each step having a first surface which is directed towards the cathode deflection point or a point behind the cathode deflection point and a second surface which extends transversely of said first surface, whereby electrons are received by the anode on said second surfaces predominantly.
Claim 2
Dependent Claim
138 words
An X-ray tube for use in determining the electron density in a part volume from the scattering of X-rays received from several directions, said X-ray tube comprising a cathode, an anode which is symmetrical with respect to rotation about a predetermined axis and is positioned to receive a beam of electrons from said cathode, and means for causing the electron beam both to scan the anode in a radial direction with respect to said axis and to rotate about said axis, and wherein said anode is formed in the radial direction with steps, each step having a first surface which is directed towards the cathode deflection point or a point behind the cathode deflection point and a second surface which extends transversely of said first surface, whereby electrons are received by the anode on said second surfaces predominantly.
Claim 3
Dependent Claim
36 words
An X-ray tube as claimed in claim 1, wherein the anode is a transmission anode and said first surface of each step is substantially flat and defines a plane in which the cathode deflection point lies.
Claim 4
Dependent Claim
30 words
An X-ray tube as claimed in claim 1, wherein the anode is a reflection anode and is formed in such manner that it is substantially screened against undesired backward emission.
Claim 5
Dependent Claim
24 words
An X-ray tube as claimed in claim 1, wherein the steps are arranged in radially-extending rows, the steps of adjacent rows being mutually staggered.
Claim 6
Dependent Claim
65 words
An X-ray tube as claimed in claim 1, 2, 3 or 4, further comprising a collimator positioned to receive X-rays emitted from the anode, the collimator comprising a block of dense material formed with passages extending therethrough to focus X-rays upon a part volume under examination, each passage being defined by a central axis which passes through said first surface of one of said steps.
References Cited (Backward Citations)
US3106640A
Cited
US3942015A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-04-22 | 1983-10-22 | 1984-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-22 | 1987-10-22 | 1988-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-22 | 1991-10-22 | 1992-04-22 | $7700.00 | Window Closed / Lapsed |