中紅外光是波長3-50微米的電磁波，由於其波長剛好位於許多基礎化學鍵的吸收波段，因此在生物以及化學上有廣泛的應用，是許多科學研究很有興趣去產生與發展的光源。本研究的主題就是產生中紅外光源，然而中紅外光並不像一般常見的雷射是利用其雷射增益介質的能階特性來發光，一般很難找到一個雷射增益介質可以自己產生中紅外光，因此中紅外光的產生通常都得依賴非線性光學效應。本研究是利用光參放大這個非線性光學效應來產生中紅外光脈衝，我們使用鈦藍寶石雷射放大器做為幫浦光，其脈衝寬為25飛秒、重覆率為1000赫茲、中心波長在800奈米。我們將幫浦光分出一小部分來產生白光連續得到信號光，其中心波長在1064奈米。最後光參放大產生的閒置光為中心波長在3224奈米的中紅外光超短脈衝。本論文詳細地說明了如何決定非線性晶體(磷酸氧鈦鉀, KTP)、實驗的原理與架構以及使用光參放大產生中紅外光脈衝的好處。文中呈現了模擬以及實驗的結果，證明了本研究成功以光參放大產生了中紅外光超短脈衝，其中心波長在3.2微米附近，將來若使用適當的脈衝壓縮技術，脈衝寬有機會達數十飛秒。

Mid-infrared refers to electromagnetic waves in the wavelength range of 3-50 μm, thus the development of mid-infrared is important for the studies of chemistry,
physics and biology. Optical parametric amplification (OPA) is a nonlinear optical effect that is commonly used to generate mid-infrared pulses. We have designed a simple OPA system pumped by a Ti:sapphire laser amplifier that produces 25 fs pump pulses at 1 kHz repetition rate with wavelength range centered at 800 nm. We have tapped a small part of energy of a pump pulse to generate a signal pulse centered at 1064 nm via white-light continuum. The idler pulses we have gotten by OPA are
mid-infrared ultrashort pulses. This thesis explains how we chose the parameters of the nonlinear crystal, the theories of the mechanisms involved in the experiment,
experimental setup, and the advantages of this OPA system in detail. In this thesis we have shown the numerical simulation and the experimental results to prove that we
have successfully generated mid-infrared ultrashort pulses. Its wavelength range is centered at 3200 nm. If the mid-infrared pulses we generated are compressed properly in the future, its pulse duration will have a good chance to reach tens of femtoseconds.

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