摘要:
It is described an X-ray tube (100) comprising a rotating anode (130), which is provided with a pull electrode (140). The pull electrode (140) interacts with a fixed electron source (110) in order to generate a modulated electron beam (120a, 120b). The beam modulation may be an intensity variation and/or a spatial deflection. The pull electrode (140) is mounted in a fixed position with respect to the anode (130) and rotates together therewith. The pull electrode (140) may have a hole (141) for passing the electron beam (120a). When being in front of the electron source (110), the pull electrode (140) causes a high electric field (142a) such that a strong electron beam (120a) is generated. When being not in front of the electron source (110) only a low current or a zero current electron beam (120b) is generated. However, the pull electrode (740) may also cause a radial beam deflection such that depending on the angular position of the anode (730) the position of a focal spot (721a, 721b) of the electron beam (720) is varied.
摘要:
Die Erfindung betrifft Röntgenstrahler, die als eigentliche Strahlenquelle eine Drehanoden-Röntgenröhre (1) enthalten. Dabei wird konstante Abgabe eines einheitlichen Strahlenbündels (22) angestrebt. Dies wird nach der Erfindung erreicht, indem der Brennfleck (21) der Röhre (1) mittels des Magnetfeldes einer Spule (32) am seitlichen Auswandern aus einem vorgegebenen Punkt gehindert wird. Die Erfindung ist besonders für die Stabilisierung von Röntgenstrahlern für die Röntgendiagnostik, insbesonder Computertomographie, günstig.
摘要:
Die Erfindung bezieht sich auf Röntgenröhren zur Herstellung von Körperschichtbildern mittels eines abtastend bewegten Röntgenstrahlenbündels, das auf einem ringförmigen Bereich eines Anodenkörpers erzeugt wird. Dazu liegen der Anode gittergesteuerte Kathoden in Abstand gegenüber und die Gitter werden nacheinander in einer der Abtastgeschwindigkeit entsprechenden Sequenz (Bildanzahl und Belichtungszeit) freigeschaltet. Zur Erhöhung der Belastbarkeit wird der ringförmige Bereich um eine Achse gedreht, auf der die Zentren des Bereichs und der Kathoden liegen. So kann die Geschwindigkeit unabhängig von der Herstellung der Bilder auf diejenige gebracht werden, die bei Drehanoden-Röntgenröhren benutzt ist und bei der eine optimale Verteilung der entstehenden Wärme erfolgt. Eine erfindungsgemäße Röntgenröhre ist universal anwendbar, weil auch einzelne Kathoden einschaltbar sind. Insbesondere ist sie für den Einsatz zur Herstellung von Röntgenschichtbildern nach dem Zonoskopieverfahren geeignet.
摘要:
This X-ray tube device (100) includes an anode (2) and a cathode (1) including an emitter (10) emitting an electron to the anode. The emitter includes an electron emission portion (11) in a flat plate shape, a pair of terminal portions (12) extending from the electron emission portion, connected to an electrode (1a), and a supporting portion (13) provided separately from the terminal portions, insulated from the electrode, supporting the electron emission portion.
摘要:
An apparatus (210) and method for total or partial blanking of an electron beam (e) during a jump between the 2 or more positions of a dynamic focal spot (FP) movement in circumferential direction of the electron beam impinging on the focal track (FPTR) of a rotating target disk (230) of a X-ray tube (110). Alternatively the focal spot size can be increased during this short time interval. Overheating of the anode at the focal spot can be prevented.
摘要:
Conventionally, the magnetic field generator was arranged perpendicularly to the axis of the electron beam. The magnetic field generator (4) of this invention is arranged so as to produce an asymmetric magnetic field.
摘要:
There is disclosed a rotating anode X-ray tube assembly comprising a vacuum envelope (11) integrated with an anode target (15), a housing (3) receiving at least the vacuum envelope, and rotatably holding it, a circulation path circulating a cooling medium (7) closed to at least the anode target of the vacuum envelope, a cathode (13) received and arranged in the vacuum envelope, a cathode support member (13a) supporting the cathode, a bearing mechanism and a vacuum sealing mechanism interposed between the vacuum envelope, and the housing or a stationary member directly or indirectly fixed to the housing, and a driver unit for rotating the vacuum envelope.
摘要:
X-ray tube (20) includes a rotatable envelope (11) in which is mounted an electron gun (74) at one end and a target anode (36) at the other end. A fixed means (120) for deflecting the electron beam from the electron gun is provided to deflect the electron beam on a fixed path as the envelope (11) of the x-ray tube rotates about an axis. The electron beam being confined to a fixed path (124) results in the electron beam striking various positions of the target anode to provide for improved heat dissipation. The electron beam is deflected along the fixed path using magnetic deflection means including magnetic deflection coils (120) positioned external of the envelope to provide a deflection field transverse to the electron beam. The target anode (36) is cooled by directing a cooling fluid (44,46) on an external side of the target anode.