本論文的研究主題是針對使用中心波長1550 nm的摻鉺光纖飛秒脈衝雷射系統的多種應用，以透過光空間調製器整形脈衝回饋調控方法達成在應用端獲得轉換極限脈衝或優化兆赫波訊號。首先，我們提出以三點測量值替代相位掃描之改進式相位凍結演算法於脈衝整形，可較原相位凍結演算法加速演算時間理論值26.6倍實驗值20.5倍，並同時提升相位解析度達8倍。演算前後之光強度自相關干涉圖形顯示當雷射脈寬半高寬自712.3 fs縮短至233.2 fs，與時間-頻寬乘積所估算之變換極限脈寬230.39 fs誤差僅1.2 %，可有效消除脈衝色散。
我們又進一步探討雷射脈衝特性對於基於低溫砷化銦鎵光導天線之時域兆赫波光譜量測之影響。實驗上分別嘗試以帶有色散值 -0.1 ps2 至 0.1 ps2 之脈衝雷射產生兆赫波脈衝，以及使用兩種版本之相位凍結演算法回饋調整兆赫波脈衝振幅，發現最佳激發及探測脈衝為近於轉換極限者，這與800 nm光脈衝激發低溫砷化鎵光導天線者不同。
經由量測樣品如乳糖及玻璃之兆赫波時域光譜，我們得以驗證基於脈衝整形之飛秒摻鉺光纖雷射用於各種材料之兆赫光譜特性量測之可行性。

The aim of this thesis is to achieve transform limited pulses (TLP) at application site or to optimize terahertz (THz) wave signals generated by using an erbium-doped fiber laser system (l ~ 1550 nm) and adaptive pulse shaping with a spatial light modulator (SLM). A 3-point sampling technique is proposed to replace the phase scanning approach in the algorithm for adaptive control. The present approach is theoretically 26.6 times and experimentally 20.5 times faster than the conventional freezing phase algorithm (FPA). Meanwhile, the phase resolution achieved is enhanced by eight times. From intensity autocorrelation measurement, the full-width at half maximum of an optical pulse was adaptively narrowed from 712.3 fs to 233.2 fs. Comparing to the FWHM width of 230.39 fs for a transform limited pulse (TLP), the error is 1.2 %.
In this work, we also examine the optimized pulse characteristics for a THz time-domain spectrometer (THz-TDS) based on LT-InGaAs photoconductive antenna (PCA). The dependence of THz pulse amplitudes on the dispersion of the optical pulse is studied by applying group delay dispersion of -0.1 ps2 to 0.1 ps2 to the pumping pulse. The adaptive control invokes two versions of FPA with THz peak amplitude as the feedback signal for shaping the THz pulses. We found that the best excitation and detection pulse is close to transform limited. This is different from results of previous studies on THz pulses generated from LT-GaAs PCA excited by femtosecond optical pulse (l ~ 800 nm).
Through the THz TDS measurements of lactose and glass, we are able to verify the feasibility and potential of sample characterization by a THz-TDS using pulse-shaped femtosecond erbium-doped fiber laser. 

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