強場雷射產生的錫電漿可以激發中心波長13.5奈米的寬頻極紫外光，此光源可應用於光學同調顯像儀，由於極紫外光源具備短中心波長與寬頻的特性，可為生物細胞等相關研究提供奈米尺度的縱向解析度顯影。因此我們運用解析與模擬的方法進行雷射產生錫電漿極紫外光光譜學的研究。
本論文首先介紹穩態輻射電漿光譜模型的學理基礎與架構，此物理模型以哈特里－福克原子架構程式Cowan code為基礎，並考慮能階交互作用和相對論效應，以計算穩態錫電漿中+4到+13價錫離子內部4d-4f和4p-4d的原子能階躍遷，進而推估躍遷產生的自發輻射極紫外光光源強度與電漿不透明度所造成的再吸收效應。此模型計算得到的電漿光譜特性與實驗量測相當吻合，藉由分析Nd:YAG雷射與CO2雷射產生的電漿光譜特性，得到極紫外光源之光學同調顯像儀達到最高解析度下的雷射電漿操作條件，可以做為將來實驗之參考。

The broadband extreme ultraviolet (EUV) light with a central wavelength 13.5-nm can be generated by laser-produced Sn plasmas. The broadband EUV light source can be applied on optical coherence tomography (OCT) to provide images of biological cells with nanometer-scale resolution. Therefore, the theoretic analysis and numerical methods are used to study the spectrum of the laser-produced Sn plasma EUV light source.
Firstly, the fundamentals and structure of the numerical model for a steady-state plasma spectroscopy are discussed in the thesis. Based on the Hartree-Fock (HF) atomic structure code (Cowan) with the consideration of the relativistic and configuration-interaction (CI) effects, the EUV light spectrum majorly contributed by 4p-4d and 4d-4f transitions among ions of Sn V - XVI. The numerical analysis also includes the calculation of plasma emissivity and opacity. The numerical results agree well with experimental measurements. Furthermore, the parametric studies for spectral properties of Sn plasmas produced by Nd:YAG and CO2 laser are shown in the last part of the thesis. The study can provide the optimized plasma conditions to achieve the proper EUV light source for the EUV OCT.

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