本論文展示一組泵功率1.5瓦、40公尺長的摻鉺增益光纖製成的正色散光纖振盪器，並在不同操作模態下進行量測。
利用在腔內插入液晶陣列調變器提供額外的二階及三階相位，可得到最高脈衝能量與-20 dB頻寬分別為58奈焦耳與54奈米，兩者模態之中心波長均為1560奈米。我們也發現在高幫泵功率及共振腔長過長的情況下，造成鎖模態不穩並於比中心波長頻率小於13兆赫茲(THz)的位置產生拉曼訊號。拉曼訊號的產生除了使鎖模態不穩，甚至有可能造成鎖模頻譜突然崩塌外，還影響雷射系統產生的脈衝品質，使得脈衝能量無法全集中於主脈衝上、造成能量外洩。透過長距離自相干涉訊號量測，及射頻頻譜分析等方式監測並觀察脈衝序列，推測出脈衝可能的形狀後進行長距離自相干涉訊號的模擬並與測得的實驗數據比對，超過89 % 的脈衝能量外洩，使脈衝的尖峰功率比預期得低了許多。

A normal dispersion fiber oscillator with 40-m-long erbium-doped gain fiber, 1.5 W pump power and intracavity liquid-crystal modulator (LCM) providing extra 2nd-order and 3rd-order spectral phase was demonstrated in different operation modes. The highest pulse energy and the broadest -20 dB spectral width were 58 nJ and 54 nm (the spectra of both operation modes are centered at 1560 nm), respectively. We also discovered significant Raman signal at 1669 nm (red shifted by 13 THz) at strong pump power and excessively long fiber in the cavity.
The production of Raman signal also implies there is a risk of soliton explosion (causing abrupt collapse of mode-locked spectrum) and energy leakage. By a series of experiments, such as long-range intensity autocorrelation (IA), and radio-frequency spectrum measurement, the probable pulse shape was determined. Based on the estimated pulse shape, we estimate there is over 89 % of pulse energy leaking from the main pulse, substantially reducing the peak power.

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