Rotating envelope x-ray tube
Citation, DOI & article data
Rotating envelope x-ray tubes (RET), are a relatively novel type of high-performance x-ray tube developed in the early 2000s. Their two main features are the direct contact of the anode plate with the cooling oil, and rotation of the entire envelope around the axis of the anode.
In rotating envelope x-ray tubes, unlike conventional x-ray tubes, the anode plate is part of the outer wall of the tube housing, and is in direct contact with the coolant. This results in increased heat dissipation and improved performance. Furthermore, the entire vacuum tube rotates around the axis of the anode and not only the anode plate. Since no moving parts are in the vacuum, rotating envelope x-ray tubes are significantly more compact than conventional x-ray tubes. The smaller tube size results in increased resistance against the high gravitational forces present during rapid CT gantry rotation times. rotating envelope x-ray tubes are therefore particularly useful in more demanding applications such as dual energy CT 1. In rotating envelope x-ray tubes the electron beam emerging from the centrally positioned cathode is steered using electromagnetic deflection to the focal spot of the anode.
- 1. Thomas Flohr, Bernd Ohnesorge. Multi-slice CT Technology. (2020) doi:10.1007/978-3-540-49546-8_3