本文主要利用四面鏡共振腔的設計來產生圓柱向量偏振光，利用泵源光進入雙折射晶體Nd:GdVO4後造成e-ray和o-ray的分離，做出徑向圓柱偏振或方向角圓柱偏振光。在G1G2乘積為0跟1之間的穩定區範圍內，藉由調控共振腔的長度，可以得到不同的光形變化，而當在第一段長度Z1為9.61 cm時，可在較廣的範圍內觀察到圓柱向量光束，且在特定長度下，圓柱向量光束有很小的發散角度且功率穩定，同時光在空間分佈上有著不錯的偏振度，經由M2的量測方法下，算出圓柱向量光束有低品質因子Mx和My約在3左右。

In this thesis, the design of the four-mirror resonance cavity is mainly used to generate cylindrical vector beam, which is produced by separating e-ray and o-ray from birefringence crystal Nd:GdVO4. Radially polarized beam can be cause from e-ray and azimuthally polarized beam from o-ray. In the stable range between 0 and 1, different patterns can be obtained by adjusting the length of the resonance cavity. When the first length of Z1 is 9.61 cm, the cylindrical vector beam can be observed in a wide range. Under the specific length, the cylindrical vector beam has a small divergence angle and power stability. At the same configuration, cylindrical vector beam has a good polarization in spatial distribution, and the M-squared quality factor of the cylindrical vector beam is demonstrated with a low value.

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