這篇論文中使用了桑亞克干涉儀(Sagnac Interferometor)與壓電陶瓷(PZT)來調製光源，使一連續光源(Continuous Wave)調製成週期性的脈衝，並可藉由改變輸入PZT的訊號週期來產生不同重覆率的脈衝，在重覆率為22.5kHz時，可達到約0.7μs的脈衝寬度(Pulsewidth)，並藉由調整PZT的振幅可以縮短脈衝寬度，另外本文也將探討PZT的振動週期與振幅對於雷射輸出功率與脈衝寬度的關係。
未來我們可以將此作為光時域反射儀(Optical Time Domain Reflectometor,OTDR)的光源。

In this thesis, we use a Sagnac loop with a PZT phase modulator as an on-off switch to modulate the laser output power.
The laser cavity containing such an optical modulator and a pumped erbium-doped fiber functions as a Q-switched resonator, generating a pulse train. Here, we investigate the pulse generation at different pump powers for the erbium doped fiber and voltage amplitudes of the signal applied to the PZT phase modulator. Pulse lasing with various time periods of square-wave signals applied to the PZT are also investigated. It is found that a stable pulse train can be generated at some signal periods or signal amplitudes of the square-wave signals applied to the PZT phase modulator. The width of the pulse generated can ranges from ~14μs to ~0.7μs at the repetition rates from 22.22kHz to 25kHz.

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