Bongsoo LEE^*, Kyoung Won JANG, Dong Hyun CHO, Wook Jae YOO, Hyung Shik KIM, Soon-Cheol CHUNG, and Jeong Han YI

School of Biomedical Engineering, College of Biomedical and Health Science, Research Institute of Biomedical Engineering, Konkuk University, Chungju 380-701, Korea

(Received January 25, 2007; Accepted July 18, 2007; Revised June 22, 2007)

The purpose of this study was to develop a method for measuring the one-dimensional dose distribution of a high-energy photon beam using a miniaturized high-resolution fiber-optic radiation sensor array. The measurements were made by thin plastic optical fibers with organic scintillating fiber sensor probes that emit the visible wavelength of light. The scintillating light is guided to a silicon photodiode array by plastic optical fibers in order to convert light output to an electrical signal. The one-dimensional spatial dependence of photon beam is measured by a one-dimensional fiber-optic sensor array in a poly(methyl methacrylate) (PMMA) phantom. It is shown that this fiber-optic radiation sensor has better spatial resolution than a conventional ionization chamber and much less time is required to measure one-dimensional dose distribution in the high radiation fields. The real-time and the high spatial resolution measurements due to the small detector volume make this system suitable for dosimetry in radiation therapy.

Key words: plastic optical fiber, organic scintillator, radiation sensor, one-dimensional dose distribution

^*E-mail address: bslee@kku.ac.kr