由於固態藍/綠光雷射具有高功率、短波長的特性，廣泛地應用在：微機械加工、雷射顯示器、水下探測……等等。在開發各種高功率的固態雷射過程中，若能準確預估出雷射的輸出特性，如輸出功率、雷射模態……等，對於研究開發的過程，不論是效率或是成本上皆有很大的助益。本研究之目的是利用一套光學軟體GLAD (General Laser Analysis and Design) 來模擬分析我們所設計的腔內倍頻之準三能階CW藍光雷射及四能階CW綠光雷射實驗。

就理論部分來說，GLAD不但考慮到光的波動特性如色散、繞射等，且可將各線性或非線性光電元件以模組化之方式加入程式加以分析。藉由模擬我們可以分析及預估腔內倍頻之藍/綠光雷射之輸出特性，另外，我們也針對準三能階雷射因為熱所造成的重覆吸收損耗現象加以研究探討。

另外，實驗部分，發展出藍/綠光微晶體雷射。藍光雷射部分是以3W雷射二極體幫浦，Nd:YAG 為增益介質，KNbO3為倍頻晶體的擴散結合晶體，整個雷射架構的體積更小，就共振腔部分長度為4 mm；目前實驗結果藍光雷射的輸出功率為17.6 mW。另外，我們也嘗試了用15W的光纖耦合半導體雷射來幫浦，以得到更高的藍光功率輸出。綠光雷射部分，同樣是以3W雷射二極體幫浦，但改用Nd:YVO4為增益介質，KTP為倍頻晶體的黏合式晶體，就共振腔部分長度為6 mm，實驗結果已得到627 mW的綠光雷射輸出。

Because compact solid-state blue/green lasers can generate high power, and short wavelength radiation, it is applied in micromaching, laser display, underwater ranging, and so forth. It is a very cost-effective approach to develop such lasers, if the laser output characteristics can be estimated precisely using software simulation. The purpose of this study is to use an optics software GLAD (General Laser Analysis and Design) to model our intracavity frequency-doubled blue/green lasers.

The GLAD software considers the wave nature of laser, such as dispersion and diffraction. Moreover, it employs a modular design in modeling linear or nonlinear optical components. In order to get more precised estimation of the laser output characteristics of a quasi-three-level laser, the laser model in GLAD was modified to take into account the reabsorption loss in gain medium.

In our experiment, blue/green microchip lasers were developed. We used a 3W LD to pump a quasi-three-level laser with the Nd:YAG crystal as gain medium and KNbO3 crystal as the intracavity SHG crystal for the generation of blue laser. The laser generates 17.6 mW of blue power with a cavity length of 4 mm. With almost the same structure except using Nd:YVO4 crystal as gain medium and KTP crystal as the intracavity SHG crystal for generation of green laser, the laser produces 627 mW of green power with a cavity length of 6 mm.

目錄

中文摘要 i
英文摘要 ii
目錄 iii
圖目錄 iv
表目錄 vii
第一章 緒論 1
第二章 GLAD光學模擬軟體理論分析 4
2-1光束傳播分析方法 4
2-2切開分段分析方法 7
2-3增益介質分析方法 10
2-4非線性晶體分析方法 17
第三章 數值模擬部分 19
3-1 Nd:YVO4 與 Nd:YAG 雷射晶體 19
3-2四能階雷射系統 23
3-3準三能階雷射系統 32
3-4腔內倍頻的工作原理 42
第四章 實驗的結果 51
4-1實驗系統的架設 51
4-2綠光雷射的實驗結果 56
4-3藍光雷射的實驗結果 61
第五章 結論 68
參考文獻 71
中英對照表 73
附錄1. 四能階半對稱式共振腔模擬程式 77
2.準三能階半對稱式共振腔模擬程式 85

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