Patent US3825761A successfully refreshed from Google Patents.
US3825761A
Expired / Lapsed
US
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X-ray apparatus for displaying in slow motion tissues which move with the rhythm of the heart
Assignee: US Philips Corp
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Filing: 1973-07-05
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Granted: 1974-07-23
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Expires: 1993-07-05
Abstract
Abstract A method of X-ray examination of objects that move in rhythm with the heart wherein the image information is switched on and off in synchronism with the heart action. In a preferred embodiment, the high voltage supply of the X-ray tube is switched on and off at the heart frequency and is on for a period that is short compared with the duration of one heart action.
Inventors
- 👤 E Geratsdorfer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:24
CPC Classifications
A; A61; A61B; A61B6/00; A61B6/54; A61B6/541; A61B5/00; A61B5/24; A61B5/316; A61B5/318; A61B5/346; A61B5/349; A61B5/352; H; H05; H05G; H05G1/00; H05G1/08; H05G1/62
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
151 words
An X-ray apparatus comprising an X-ray tube, a source of high voltage for the X-ray tube, a switch coupling said tube and voltage source for switching the tube voltage on and off at substantially a rate which is slightly different from the Heart frequency of a person under examination, first means responsive to the heart frequency of the person for deriving a first sequence of pulses with a repetition rate equal to the heart frequency, second means for deriving from said first sequence of pulses a second sequence of pulses of adjustable duration for controlling said switch, a delay member with a continuously variable delay being coupled between said first and second means, and control means connected to said delay member to vary the delay in a predetermined manner whereby the portion of the person being examined is displayed moving in slow motion for critical examination of the portion in motion.
Claim 2
Dependent Claim
151 words
An X-ray apparatus comprising an X-ray tube, a source of high voltage for the X-ray tube, a switch coupling said tube and voltage source for switching the tube voltage on and off at substantially a rate which is slightly different from the Heart frequency of a person under examination, first means responsive to the heart frequency of the person for deriving a first sequence of pulses with a repetition rate equal to the heart frequency, second means for deriving from said first sequence of pulses a second sequence of pulses of adjustable duration for controlling said switch, a delay member with a continuously variable delay being coupled between said first and second means, and control means connected to said delay member to vary the delay in a predetermined manner whereby the portion of the person being examined is displayed moving in slow motion for critical examination of the portion in motion.
Claim 3
Dependent Claim
72 words
An apparatus as claimed in claim 1 wherein said delay member and said control means connected to said delay member comprise a pulse duration modulator, and a sawtooth voltage generator coupled to and controlling said pulse duration modulator so that it supplies pulses whose duration depends upon the instantaneous value of the amplitude of a sawtooth voltage supplied thereto, the trailing edge of the produced pulses being utilized for controlling the switch.
References Cited (Backward Citations)
US2190389A
Cited
US2152045A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-22 | 1978-01-21 | 1978-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-22 | 1982-01-21 | 1982-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-22 | 1986-01-21 | 1986-07-23 | $7700.00 | Window Closed / Lapsed |