US3986064A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary-anode X-ray tube
Assignee: US Philips Corp
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Filing: 1974-10-10
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Granted: 1976-10-12
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Expires: 1994-10-10
Abstract
Abstract A rotary-anode X-ray tube comprising means to adjust current density measured along a dimension x of the focal spot of the electron beam on the anode such as to decrease in the direction of rotation of the anode according to 1/√x.
Inventors
- 👤 Wijbe Johannes Oosterkamp
- 👤 Dieter Marschall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:21
CPC Classifications
H; H01; H01J; H01J35/00; H01J35/02; H01J35/04; H01J35/06; H01J35/064
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
62 words
An X-ray tube having a cathode for emitting an electron beam and a rotary anode to be irradiated in a focal spot by said electron beam, comprising means for producing a current density distribution, measured along a dimension x of said spot in the direction of rotation of the anode, that decreases from a maximum value at least substantially according to 1/√x.
Claim 2
Dependent Claim
62 words
An X-ray tube having a cathode for emitting an electron beam and a rotary anode to be irradiated in a focal spot by said electron beam, comprising means for producing a current density distribution, measured along a dimension x of said spot in the direction of rotation of the anode, that decreases from a maximum value at least substantially according to 1/√x.
Claim 3
Dependent Claim
21 words
An X-ray tube as claimed in claim 1, wherein said means is provided in said cathode for generating the electron beam.
Claim 4
Dependent Claim
51 words
An X-ray tube as claimed in claim 2, wherein the emitting element of the cathode comprises a strip the cross-sectional area of which tapers in a direction at right angles to the current flow direction, the anode moving, with respect to the focal spot, towards the thinner side of the strip.
Claim 5
Dependent Claim
36 words
An X-ray tube as claimed in claim 2, wherein the emitting element at the surface facing the anode consists of an emissive material the emissivity of which decreases in the direction of rotation of the anode.
References Cited (Backward Citations)
US3801846A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-10-12 | 1980-04-12 | 1980-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-12 | 1984-04-12 | 1984-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-12 | 1988-04-12 | 1988-10-12 | $7700.00 | Window Closed / Lapsed |