本文主要使用雙折射增益晶體Nd:GdVO4和聲光調製器，透過ABCD Law計算雷射穩定區範圍 0 ≤ G1G2 ≤ 1，設計四面鏡的共振腔架構，藉此產生圓柱向量光束，並且只需調整輸出耦合鏡的位置，就能任意改變輸出光為徑向偏振光或方位角偏振光，另外給予聲光調製器15 kHz的方波產生Q開關脈衝，量測偏振度確保Q開關脈衝下，徑向偏振光和方位角偏振光依然維持良好的偏振特性，再經由Beam profile量測光束品質因子M^2 大小，得到圓柱向量光束的Mx^2、My^2 約在3附近，最後使用馬赫-曾德爾干涉儀去觀察相位變化，發現不管是徑向偏振光或方位角偏振光皆為拓樸電荷l = 1 的光學渦流。

SUMMARY
In the thesis ,we mainly use a birefringent laser crystal and an Acousto-Optic Modulator (AOM) along with a four-element cavity (The stable region (0 ≤ G1G2 ≤ 1) was calculated through ABCD Law for further cavity design) to generate cylindrical vector beams. By adjusting output coupler’s position, we can manipulate the output beam to be radially- or azimuthally-polarized. Moreover, Q-switched laser beams can be obtained by adding a 15 kHz square wave signal to the AOM. The high percentages of DOP indicate that the output beams still maintain good polarization quality. Next, the beam quality factor M^2 was measured by beam profile ,and then the results of Mx^2 and My^2 were about 3, which is the theoretic value of LG01 mode. The results brought us to the exploration of the vortex characteristics, which were verified by the Mach-Zehnder interferometer. We found out that whether the output beam was radially- or azimuthally-polarized beam, the topological charges l were 1.

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