電致光吸收調變器(EAM) 已被知其具有高轉換效率、飽和吸收體特性，較高的非線性現象且容易操作在高速。本文中，我們利用具高速特性的EAM以主動鎖模的方式，來產生短脈衝光。架設中我們以掺鉺光纖放大器作為增益介質，是因為它有較寬的操作波段(約1530nm-1570nm)且較高的增益飽和功率。
我們以4GHz的微波訊號源驅動，以主動鎖模方式，成功地產生了脈衝光，由於受限於光濾波器頻寬，我們得到的是半高寬為21.2 ps的短脈衝光序列，其光輸出可高達10 mW。再經由光頻譜分析儀，電頻譜分析儀以及取樣示波器的量測，得到了清晰穩定且基頻為4Ghz的訊號。藉由調整光路徑長度，我們發現EAM在最大的光傳輸有最短的光脈衝寬度、最大的光電流，這現象的主要機制是EAM飽和吸收所造成!

Electroabsorption modulator (EAM) has been known with high transmission efficiency, saturation absorber, the high nonlinearity and high speed. In this work, we use a high-speed EAM in a fiber ring structure to generate short pulse train by active mode-locking method. Inside the cavity, Erbium Doped Fiber Amplifier (EDFA) is adopted as the gain medium due to its wide operation wavelength range (about 1530nm to 1570nm) and high gain saturation power.
The mode-locked optical pulse train driven by a 4 GHz microwave source has been successfully designed and measured with filter-limited 21.2 ps pulse width (FWHM) and output power of 10 mw. Clean and stable level of signal with fundamental frequency of 4GHz is obtained through the measurement by optical spectrum analyzer, electronic spectrum analyzer and sampling scope. By tuning the optical path, the highest optical transmission with the shortest pulse and the largest photocurrent is found in EAM, indicating the dominated mechanism is the saturation of optical absorption.

第一章 序章
1.1鎖模光纖雷射概述
1.2簡介鎖模雷射
1.3電致光吸收調變器的特性
1.3.1高轉換效率特性
1.3.2飽和吸收體特性
1.4研究動機
第二章 實驗架設與說明
第三章 實驗結果與分析
3.1 EAM的特性量測
3.1.1 Transmission曲線
3.1.2 Single pass EAM的量測
3.1.3飽和吸收體特性量測
3.2摻鉺光纖雷射之量測
3.3主動鎖模摻鉺光纖雷射之量測
第四章 結論
4.1結論
4.2討論與改善工作
參考資料與文獻

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