微型 Er:YAG 雷射之開發及優化

Development and optimization of a miniature 2.94 μm Er:YAG laser

喻加(Cha Yu)

指導教授 ： 游漢輝 ； 董玉平

國立中央大學/理學院/光電科學研究所/碩士(2008年)

摘要

波長 2.94 的 Er:YAG 雷射在生物及醫學上有相當多的應用，本論文是要開發出攜帶型的 Er:YAG 雷射採血機的原型，並且將它優化。為做到縮小體積和提昇效率，我們利用文獻中的理論模型和光譜參數，運用數值方法來進行設計及優化。我們用數值模擬，分析了為量子效率大於一的現象和雷射脈衝延續到泵激脈衝之後的現象，也討論光譜參數的不準確對模擬的結果造成之影響。
為提高數值模擬的準確度，必須找到雷射共振腔內的被動損耗，但由於 Er:YAG 不是理想的四能階雷射，傳統找損耗的方法在理論上是無法正確的量測出被動損耗。對此現象，本論文提出了一個數值模擬的結果，其中說明了傳統方法的可行性，進而量測出我們實作出來的 Er:YAG 雷射的被動損耗，同時也只用了四種輸出耦合鏡的反射率，就找到各種雷射輸出能量下的輸出耦合鏡反射率之最佳值。

關鍵字

固態雷射 ； 採血

並列摘要

The principal objective of this thesis is to develop a miniature Er:YAG laser, and to collect blood with it. The performance of a flashlamp pumped miniature 2.94 ?m Er:YAG laser is optimized by using a mathematical model. The model is based on the rate equations with spectroscopic data including energy transfer processes. Using this model, we can explain the phenomenon of great-than-unity quantum efficiency and the experimental phenomenon that the laser pulse slightly extends beyond the pumping pulse in some cases. We found passive loss of our laser system. A method of optimizing the reflectivity of the output coupler was also presented.

並列關鍵字

solid state laser ； Er:YAG ； blood sampling

參考文獻

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