EBT2 自顯影底片的有效原子序與水接近所以在臨床放射線劑量的測量上有弱的能量依存特性,這種特性使得使用不同能量之劑量轉換曲線來做劑量轉換時之誤差降低。本實驗所使用之EBT2 底片為ISP 公司所開發展之免顯影定影底片及EPSON Expression 1680 平台式全彩影像掃描器，利用近接治療射源銥-192 照射EBT2 底片取得銥-192 之特性曲線，比較與6 MV 直線加速器照射底片所得特性曲線。利用EBT2 底片弱能量依存性特性，在銥-192 射源照射下，配合自製矽膠條夾EBT2 底片直接套用6 MV 特性曲線校正PTW T9112 直腸劑量偵檢器，最後取得其校正因子。研究結果發現，在EBT2 底片弱能量依存性特性之下6 MV 光子能量與銥-192 近接治療射源其底片特性曲線非常相近，利用EBT2 配合自製矽膠條可以取得EBT2 底片中軸線上之劑量分佈，藉此校正PTWT9112 直腸偵檢器內5 個二極體偵檢器，取得其在固態水假體中校正因子為2.98×107 至3.99×107 cGy/C。本研究建立將EBT2 底片用於對近接治療之絕對劑量測量流程，並用於對其他劑量計做校正因子測量。除此之外也設計並製作可用於測量體內直腸劑量之裝置，進一步分析其劑量特性做為下階段用於臨床測量之準備。

EBT2 Gafchromic film is tissue equivalence and energy independence, this characteristic can makes dose conversion and decrease error in different energy by using calibration curve. This study use EBT2 Gafchromic film manufactured by ISP and Epson 1680 flatbed scanner. Using Ir-192 source to irradiated EBT2 film and obtained the calibration curve, compare the calibration curve of Ir-192 with 6 MV photon beam. Dose calculation can be used silicon rod and EBT2 film to corrected PTW T9112 rectal detector and to acquired the correction factor. Result show that two different calibration curves of Ir-192 source and 6 MV photon beam are not significant different. Applying EBT2 film combine with silicon rod can achieve the axial flat dose to corrected PTW T9112 rectal detector. The correction factor is 2.98×107 to 3.99×107 cGy/C in solid water phantom. This study provided procedure for measure treatment dose and calibrates the other detector by EBT2 film.