中文摘要
藍/綠光雷射短波長輸出特性，使其可廣泛應用於微機械加工、雷射顯示器、資料儲存、水下通信…等方面。近年來人們一直致力於簡化高功率藍/綠光雷射架構並降低其成本，因此各種藍/綠光雷射技術皆被深入探討研究，其中又以半導體雷射激發之固態藍/綠光雷射，配合腔內( intracavity )倍頻( second harmonic generation；SHG )技術，是目前最有效產生高功率輸出與長生命期之藍/綠光雷射製作方式，在共振腔設計上，又以直接鍍膜於黏合式晶體前後端面作為共振腔其體積最為小巧。由於Nd:YAG之倍頻藍光雷射在物理機制上屬於準三能階( quasi three level )雷射系統，使得藍光雷射在技術開發上除了激發功率強度的考量外，更有別於四能階雷射系統，散熱問題將扮演著更重要的角色。

在高功率固態雷射研製過程中，若能配合光學模擬軟體在雷射系統上進行適當地評估分析，如:聚焦系統效能分析、鍍膜參數選擇、雷射輸出模態…等，對於整個雷射系統開發過程，無論在效率上或是成本上皆能產生很大助益。因此實驗前除了使用光學軟體ZEMAX來選擇所需聚焦元件，及估量架設時所需的相對位置；並嘗試以雷射系統分析設計軟體GLAD ( general laser analysis and design )，來模擬分析實驗室所開發的腔內倍頻準三能階CW( continue wave )藍光雷射。

實驗中我們利用適當的透鏡聚焦、熱導管散熱、晶體座角度旋轉之以及對幫浦波長穩定控制，在共振腔長約4 mm條件下，藍光輸出功率可達到192 mW，就文獻所知，在此小體積架構下，此結果是目前最高的功率輸出，若能藉由lens duct 此光學元件進行聚焦，將使整體架構更為簡單。

Abstract

As blue/green laser has a short wavelength radiation, it can be applied to micro-machining, laser display, high-density optical data storage, underwater communications, and so on. Large efforts have been devoted to simplify the laser system and reduce the cost. Therefore, various types of blue/green lasers have been studied, especially intracavity frequency doubling of the diode-pumped solid-state laser, which can effectively generate high blue/green laser powers with long lifetime. Among all cavity designs, direct-coated composite crystal is the most compact structure. Compare with the green laser, which is a four-level laser, blue laser belongs to a quasi-three-level system. Thus, it is more important to control the temperature of gain medium.

Before the experiment, making an estimation will greatly benefit the progress and efficiency. ZEMAX was utilized to simulate the focus system and GLAD was used to model our intracavity frequency-doubled blue laser.

In the experiment, we used a LD array as a pumping source and arranged suitable lens to reduce the array’s spot size. The laser crystal was mounted onto a copper mount which was cooled by the Vapochill cooling system. In addition, we also tried to rotate the crystal and obtained a peak power of 192 mW with only 4 mm cavity length. The result is the highest output power of microchip blue laser to our knowledge. Using lens duct as the pump transport optics can further miniaturize this composite-chip blue laser.

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 固態藍光雷射之基本原理
2-1準三能階與四能階雷射系統 5
2-2 Nd:YAG與Nd:YVO4增益介質之比較 8
2-3倍頻理論 14
2-4藍光非線性晶體之比較 26
第三章 聚焦系統與共振腔之模擬分析
3-1半導體雷射陣列之聚焦設計與分析 28
3-2 GLAD原理 43
3-3 Nd:YAG準三能階雷射之數值分析 52
第四章 高功率Nd:YAG藍光雷射
4-1藍光雷射系統架構 57
4-2熱導管溫控系統之工作原理 66
4-3實驗結果與分析 71
第五章 結論 83
參考文獻 84
中英對照表 87
附錄1 .準三能階半對稱式共振腔模擬程式(未修正下能階電子數) 91
附錄2 .準三能階半對稱式共振腔模擬程式(修正下能階電子數) 95

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