本論文利用全光纖雷射來製作Lidar測距平台，利用976 nm雷射二極體經過雷射架構產生1590 nm eye-safe波段雷射，並在輸出端分成兩個port，一個為比較端(port 3)，另一個為輸出與接收端(port 4)，利用端面平切的4%反射訊號能量與打到物體回傳的訊號能量，兩者脈衝的時間差，使用波型平移、調整倍率和數學相關性分析方法來計算我們測距的長度。在本實驗一開始我們測距所量到的波型有許多不準的地方，像是接收到的能量訊號太小很難辨認出是否為我們要的訊號還是一般的雜訊，或是打到物體所回傳的訊號與原訊號的波型相似度不高。所以我們改換雷射架構，將原輸出與接收端在同一條光纖改成分成兩條光纖分別接到示波器不同的channel，就不會互相干擾訊號，並使用纖核直徑105 nm的光纖作為接收端光纖，使接觸面積比原本纖核直徑8.2 nm大了許多，之後實驗所測到的波型經過上述分析後也與原訊號的相似層度提高很多，能量也有所提升，後面我們又調整示波器功能和使用數學Cross correlation分析方法改善每次測量的標準差，最後我們將接收端換成Double clad光纖和改善光源輸出失焦，在相同距離測量下，能量訊號可達到800倍以上，並估計可以測距到10.20公尺以上的距離。

In this thesis, the all-fiber laser is used to fabricate the Lidar ranging platform. The laser diode of 976 nm is used to generate the 1590 nm eye-safe laser through the laser structure, and is divided into two ports at the output end. One is the comparison port ( port 3), the other is the output and receiving port (port 4). We measured two pulses time difference from the 4% reflection signal energy that is flatly cut by the end face and the signal energy that is returned from the object. After that, we calculated the distances by using the wave type shift, adjusting the magnification and the mathematical correlation analysis method. At the beginning of this experiment, we found that the waveforms measured by the ranging was not precise, because the energy signal received is too small to identify whether it is the signal we want or the general noise and the similarity between the signal returned by the object and that of the original signal is not high. Therefore, we improved the laser structure, and changed the output and receiving port from the same fiber into two fibers to receive different channels of the oscilloscope. The signals won’t interfere with each other. We used fiber with a core diameter of 105 nm as the receiving end so that the fiber has a much larger contact area than the original fiber core diameter of 8.2 nm. After the mathematical analysis, we found that the waveforms had also increased the similarity of the original signal, and the measured energy had also improved. Later, we adjusted the oscilloscope function and used mathematical-cross correlation analysis method to improve the standard deviation. Last, we replaced the receiving port with double clad fiber and improved the output of the light source out of focus. Under the same distance measurement, the energy signal could reach more than 800 times, and currently we can measure distance more than 3 meters.

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