現今最常見的商用光刺激發光劑量計(OSLD)材料為Al2O3:C，此材料於低能量光子場下會有能量依存性的問題，因此本論文利用自製雙晶片指環劑量計來克服能量依存性誤差，先以蒙地卡羅模擬不同光子能量下的響應，並透過實際照射不同能量射質的X-ray來驗證雙晶片系統能有效修正誤差。另外，本論文也將自製的指環劑量計搭配近期新興的商業性材料BeO一同測試，模擬結果顯示BeO的能量依存性很低，並透過實際照射以驗證模擬結果之準確性。Al2O3:C於特性實驗中可歸納出其再現性與均勻性偏差程度不大，幾乎於±10%之內，使用自製計讀儀亦可達到重複計讀的效果。而BeO的部分，再現性幾乎於±2%以內，其均勻性浮動程度較大可透過個別校正來克服。此外，BeO於重複計讀方面的效果較差，但可透過定量的訊號衰減程度修正計數值。整體結果分析，兩種材料於自製的指環系統中均能有效的評估手部劑量。

關鍵字:光刺激發光劑量計、氧化鋁、氧化鈹

At present, The most common commercial optical stimulation luminescence dosimeter (OSLD) material is Al2O3:C. The energy dependence cannot neglect in low-energy photon fields for Al2O3:C material. Therefore, this study used a homemade dual-chip ring dosimeter to correct the energy dependence effect. First, Monte Carlo simulation was used to simulate the OSLD dose responses in the different photon energies, and verified by means of actually irradiating X-rays with different energy radiation qualities to the dual-chip system. In addition, this study also used the homemade ring with BeO dosimeter inside, which is a new commercial material developed in recent years. The simulation results verified that the energy dependence of BeO is very low, and the simulation results was verified through actual irradiation experiments. Al2O3:C can be concluded in the characteristic experiments that its reproducibility and homogeneity deviations are not large, almost both within ±10%. The homemade reader system proved the ability of repeated reading of Al2O3:C OSLD. For BeO, the reproducibility is almost within ±2%, and the degree of homogeneity fluctuation can be overcome by individual correction. The effect of repeated reading ability is not good, however, by means of the quantitative signal attenuation counting value can be corrected. In conclusion, both Al2O3:C and BeO OSLD materials can effectively evaluate the hand dose in the homemade ring system.

Keywords: Optical Stimulation Luminescence Dosimeter, Al2O3:C, BeO

中文摘要 I
Abstract II
致謝 III
目錄 IV
表目錄 VIII
圖目錄 IX
第一章 緒論 1
1.1前言 1
1.2 OSLD材料特性與原理簡述 2
1.2.1 OSLD計讀原理 2
1.2.2 OSLD材料特性簡述 4
1.3指環結構與偵檢器形式介紹 7
1.4文獻回顧 10
1.5研究動機 11
第二章 材料與方法 13
2.1 蒙地卡羅模擬(Monte Carlo method) 13
2.1.1 蒙地卡羅程式簡介 13
2.1.2 模擬流程 13
2.1.3 模擬的幾何條件與構圖 16
2.2不同材料劑量計之實驗設備 20
2.2.1 Al2O3:C雙晶片劑量計實驗設備 20
2.2.2 BeO單晶片劑量計實驗設備 23
2.3 照射場所與實驗假體 25
2.4 指環劑量計特性研究實驗步驟 29
2.4.1 再現性與均勻性評估 29
2.4.2 OSLD指環劑量校正曲線 30
2.4.3 最低可測值評估(Lower Limit of Detection,LLD) 31
2.2.4 劑量計重複計讀測試(Repeatable reading test) 34
2.4.5 訊號消光(Fading)程度 34
2.4.6 回火(Annealing) 36
第三章 結果與討論 38
3.1 MCNP模擬結果 38
3.1.1 Al2O3:C不同能量下 R1/R2模擬結果 38
3.1.2 Al2O3:C能量依存性模擬結果 40
3.1.3 BeO能量依存性模擬結果 43
3.2 不同能量光子場下的實際照射實驗 46
3.2.1 Al2O3:C自製計讀儀穩定性評估測試 46
3.2.2 照射不同能量光子以驗證能量依存性模擬結果 47
3.2.3 Al2O3:C雙晶片劑量計演算法驗證實驗 50
3.2.4 BeO劑量計於不同能量光子場下的照射結果 52
3.3 再現性與均勻性 53
3.3.1兩種材料於再現性的表現 53
3.3.2 兩種材料於均勻性的表現 55
3.4 劑量校正曲線 57
3.5 背景值測定與最低可測值評估 59
3.6 重複計讀特性測試結果 63
3.6.1 Al2O3:C劑量計重複計讀結果 63
3.6.2 BeO劑量計重複計讀結果 64
3.7 訊號消光實驗結果 65
3.8 回火程度測試結果 66
第四章 結論 69
參考文獻 71
附錄 75
附錄一 Al2O3:C再現性與均勻性計數值 75
附錄二 BeO再現性與均勻性計數值 76
附錄三 BeO指環劑量計個別校正曲線 77

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