• N. Saotome, T. Furukawa, T. Inaniwa, Y. Iwata, T. Kanai, A. Nagano, K. Noda, S. Sato, T. Shirai, E. Takeshita
  NIRS, Chiba-shi
• T. Kohno
  TIT, Yokohama

The screen monitor system is an important tool for beam diagnostic of the high-energy-beam transport line at the Heavy-Ion Medical Accelerator in Chiba (HIMAC). We have developed a very thin fluorescent film and high speed charge-coupled-device camera. Because the fluorescent film is very thin (ZnS:Ag 2mg/cm³), the beam is measured with semi-non-destructively. Consequently we can use more than two monitors at the same time and multiple locations. Moreover we employ a high-speed three-processer for image processing, the system can be applied for online monitoring and interlock system (100Hz). When the beam profile measured by this system is inevitably changed over the setting tolerance during therapeutic irradiation for the patient, the beam is immediately turned off. The design and measurement result by irradiation test are discussed.