An adjustable collimator for neutron therapy
| Autor: | K Finding, C. J. Parnell, D K Bewley, B C Page |
|---|---|
| Rok vydání: | 1981 |
| Předmět: |
Neutrons
Physics Radiological and Ultrasound Technology Field (physics) Plane (geometry) business.industry Cyclotron Right angle Collimator Neutron radiation Rotation law.invention Fast Neutrons Radiotherapy High-Energy Optics law Radiology Nuclear Medicine and imaging Particle Accelerators Stepper business Technology Radiologic |
| Zdroj: | Physics in Medicine and Biology. 26:711-714 |
| ISSN: | 1361-6560 0031-9155 |
| DOI: | 10.1088/0031-9155/26/4/014 |
| Popis: | Describes a system of adjustable collimators installed on the fast neutron beam (16 MeVd on Be) from the MRC Cyclotron at Hammersmith Hospital. A vertical section through the midplane of the collimators is shown. They consist of pairs of jaws moving in two planes at right angles to each other. The jaws defining the vertical extent of the field are divided into two sections, one near the target and the other acting as a trimmer. In the other plane there is only a single pair. The edges project back to the outside of the target, an area of 2 cm*2 cm. The outer end of the trimmer is at 100 cm from the target. At the treatment distance of 135 cm the field size is set by limit switches between 3 cm*3 cm and 20 cm*20 cm. The jaws can be rotated through +or-50 degrees so that the field can be inclined at any desired angle. The drives to the pairs of jaws and to the rotation of the collimator use DC stepper motors. These, together with the appropriate electronic control circuitry, provide precise and rapid positioning of the jaws. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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