本篇論文旨在探討被動式Q值轉換雷射的理論與搭設,並且使用體積式布拉格光閘(Volume Bragg Grating) 來消除共振腔內的縱態模。其中使用參雜1 % Nd的Nd:GdVO4 當作增益介質(Gain Medium),使用 Cr:YAG當作飽和吸收晶體(Saturable Absorber)。本篇論文將會深入討論被動式Q值轉換雷射的理論並且依序搭建四套不同的雷射系統。四組雷射系統分別為(1) 線性共振腔連續輸出雷射 (2) 線性共振腔被動式Q值轉換雷射 (3) V型共振腔連續輸出雷射 (4) V型共振腔Q值轉換雷射。在第三跟第四組雷射系統中加入體積式布拉格光閘,以比較體積式布拉格光閘對消除縱態模的重要性。另外,本篇論文將會使用另外一種飽和吸收晶體 Cr:YVO4來嘗試搭建被動式Q-值轉換雷射。
In this thesis, the theory of Passively Q-witched Laser will be discussed in detail. A Volume Bragg Grating (VBG) was used to eliminate longitudinal mode in cavity. The gain medium was Nd:GdVO4 with 1% Nd doped and the saturable absorber was Cr:YAG. There were four laser systems finished step by step including (1) CW laser generation with linear cavity (2) passively Q-switched laser generation with linear cavity (3) CW laser generation with V-type cavity (4) passively Q-switched generation with V-type cavity. VBG was used in the third and the fourth system to compare with the first and the second system which without VBG. Another saturable absorber Cr:YVO4 was used to try to build a passively Q-switched laser.