ABSTRACT
MD-55-2 is one of the Radiochromic film models with the sensitivity suitable for dose measurements ranging from 5 to 100 Gy. However, this lower limit makes the film impractical for its applications in many areas such as brachytherapy source dosimetry. n this project, the useful range of the film has been extended by using a multilayer film technique. In this technique, single-, double-, and triple- layers of films were exposed to the doses ranging from 0.5 to 10 Gy using a Co-60 photon beam. Calibration curves for corresponding layers of films were obtained with a spectrophotometer using a 680nm wavelength. The results indicated that the sensitivities of double and triple layers were approximately 200% and 300%, respectively, higher than a single-layer film. The impact of multilayer film arrangement on the energy dependence of the MD-55-2 Radiochromic film has also been examined using 100KVp, 80 KVp, and 6 MV X-ray beams. The results indicated an insignificant [within 5%] change in film responses with the beam energy. Therefore, the multilayer technique enhances the Radiochromic film sensitivity and expands its application to the low dose range in field of brachytherapy source dosimetry