就波長穩頻而言，我們成功的把波長頻率漂移量由約100MHz 降至小於1~5MHz，將半導體雷射的頻率鎖定在358660.800GHz。然實 際上我們應可將頻率漂移量再降低，但受限於多外在的問題，例如也 許是PZT反應時間太慢追不上光頻率的變化；或是電流源本身的擾動 以及溫度變化的影響所造成對半導體雷射的輸出頻率有幾個MHz擾動 等等，故僅能得此結果。
若能採用將相位檢測器輸出的誤差訊號經高頻濾波器直接注 入至雷射二極體中應該可以更高速地控制雷射的頻率【26】，再配合PZT 來迴授控制雷射頻率使穩頻的時間可以加長，相信應可將頻率穩定度 提高。另一方面若我們能控制好外部環境減少對半導體雷射的影響，
將外腔雷射架設在一特定基板上對整個外腔雷射系統進行溫控，並將 整個外腔罩住避免外界聲音的影響，使雷射頻率自由漂移量更少，則 頻率穩定度相對的亦將提高。
做這一個雷射互鎖實驗中所遇到的問題與困難最主要的有兩 項：第一項是飛秒鎖模雷射在波長835nm左右部分的光強度較弱，使 得與半導體雷射拍頻的訊號不強訊譟比較低，也使得在對光時難度增 加以及在互鎖時的效果沒有很好。第二項是外腔雷射所以用的雷射二 極體本身就具有小的共振腔，所以當我們架設外腔時要使外腔的光強
度高於內腔的光強度，這使得調整的難度加大，若沒有調整好，在互 鎖時兩個腔的模態會有彼此互相搶奪增益的情況發生讓輸出光不 穩，造成拍頻訊號被雜訊淹沒，而使互鎖失敗。
現在的頻率量測儀器中，能夠精確的量測微波訊號頻率的最大範 圍只有在幾十個 Giga Hz 內，若是想要量測到 THz 這種更高頻率的訊 號就必須要靠一些 THz 量測系統，經由那量測系統上取得到我們所要 的資訊，通常取一筆數據要花很長的時間。因此我們希望藉由光脈衝 雷射和連續波半導體雷射的互鎖，令脈衝雷射的諧頻用來當作連續波 半導體雷射鎖定的頻率標準。實驗的方法是我們先將雙波長連續波外 腔式半導體雷射所輸出的雙波長雷射光與脈衝雷射產生出拍頻訊 號，再利用鎖相迴路與銫原子鐘做鎖定，這樣一來當我們將半導體雷 射和鎖模雷射互鎖時，這時的銫原子鐘就可以來追朔半導體雷射與脈 衝雷射的差頻訊號。這時只要兩個外腔雷射的差頻能到 THz 的等級，
我們就能利用這兩個外腔半導體雷射來做差頻生成頻率準確穩定的 THz 輻射波。雖然要完成 THz 輻射波的頻率標準進而追朔到 THz 的頻 率資訊還有不少缺點等待改進，我們這一個論文算是完成雷射互鎖的 第一步。THz 產生器則是高速資訊中不可或缺的關鍵元件。而本論文 所研究之成果將可作為 THz 量測的重要基礎。
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