主動式Q開關綠光雷射之優化研究

Abstract

本論文的目的是透過線性共振腔來開發可靠穩定的主動式Q開關綠光雷射。首先，我們使用不同的前鏡來探討共振腔配置對Q開關脈衝形狀的影響。實驗結果顯示，凸平腔是最合適的共振腔設計，能獲得最短的脈衝寬度和良好的脈衝形狀。除此之外，我們在凸平腔的設計上，使用不同曲率半徑的前鏡，來研究雷射輸出功率的表現。我們實驗發現，合適的激發功率與前鏡的曲率半徑有密切的相關性。前鏡的曲率半徑越大，合適的激發功率越低。最後，我們研究發現脈衝間的穩定性取決於縱模的相位鎖定。初步結果顯示，相位鎖定的性能與前鏡的曲率半徑無關。這項研究工作不僅使我們能夠實現可靠的主動式Q開關532nm雷射，而且還為不同輸出功率的Q開關雷射提供了一些重要的見解。

The aim of this thesis is focused on developing reliable active Q-switched lasers at 532 nm based on linear cavity configuration. First of all, we demonstrate the influence of cavity configuration on the Q-switched pulse shape by using different front mirrors. Experimental results reveal that convex-plano cavities are the most suitable cavity design to obtain short pulse width and excellent pulse shape. Moreover, based on convex-plano cavities, we utilize different radii of curvature of front mirrors to explore the performance of laser output. We experimentally find that the suitable pump power range is strongly dependent with the radius of curvature of front mirror. The larger radius of curvature of front mirror, the lower suitable pump power. Finally, we explore that pulse-to-pulse stability depends on the performance of phase locking between longitudinal modes. Preliminary results show that the performance of phase locking is independent with the radius of curvature of front mirror. This work not only enables us to realize reliable active Q-switched lasers at 532 nm, but also offers some important insights for Q-switched lasers at different output powers.