本文以研究投光方式對雷射光在生物組織中的傳播及其熱響應的影響為目的，以葡萄酒樣色素斑為研究對象，提出一簡單皮膚模型，利用Delta蒙地卡羅法模擬雷射在組織內的被吸收能量分佈，其結果再結合熱傳方程式，以求得組織中的溫度分佈，再以阿瑞尼阿斯方程式求得各個時間步驟的組織損傷分佈。

　　本研究的結果顯示：在能量分佈方面，利用凸透鏡聚焦會使血管及表皮的能量吸收密度增加，不過會降低血管及表皮的能量吸收密度比值。利用多光束入射可以在表皮的吸收不會增加太多下，增加血管的組織吸收。在溫度及損傷分佈方面，在不破壞表皮組織的前提下，結果顯示使用多光束聚光方式治療效果比單透鏡聚焦投光方式更佳。

　　The purpose of this research is to examine the light propagation and the thermal response in tissues with different ways of laser-light delivering. In this work, we take the port wine stain as an example, and adopt a simple skin model. To obtain the energy deposition, we use the Delta Monte Carlo method to simulate the light propagation. Then we solve the heat conduction equation to obtain the temperature distribution. Finally, we use the Arrhenius rate process equation to get the thermal injury for each time step.

　　The results show that using the convex lens can increase the deposited energy in the blood vessel and the epidermis, but reduce the ratio of deposited energy in the blood vessel and the epidermis. The multibeam projection of laser can increases the deposited energy of the blood vessel without increasing the deposited energy of the epidermis too much. In the temperature and damage distribution aspect, under the requirement without destroying the epidermal tissues, the results show that the treatment by using multibeam with lens focusing is better than that using single focusing lens.

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