本論文著重於一個可用在雷射誘導損傷閾值(LIDT)測試的1064奈米鈮摻鉻鋁石（Nd:YAG）雷射系統，用於實驗室中光學塗層的雷射誘導損傷閾值測試。此雷射系統包含一套脈寬為10奈秒的被動式Q開關(Q-switch)種子雷射，以及兩級分別由雷射二極體以及發光二極體泵浦的四通放大器。雷射系統可輸出100毫焦耳的1064奈米雷射脈衝。
為了提供雷射誘導損傷閾值測試不同波長的雷射，雷射系統增加了2倍頻、4倍頻以及光參產生器的架設。實驗中以一8*8*6毫米的磷酸氧鈦鉀(KTP)晶體產生二倍頻雷射。該架設在輸入70毫焦耳脈衝能量的1064奈米雷射時可產生25毫焦耳的532奈米雷射。產生的二倍頻532奈米雷射再經由一7*7*6毫米的偏硼酸鋇(BBO)晶體產生四倍頻雷射。當輸入25毫焦耳脈衝能量的532奈米雷射時可產生10毫焦耳脈衝能量的266奈米雷射。光參產生器部分，利用5公分長、週期29.8微米的週期極化反轉鈮酸鋰產生104毫焦耳、1576奈米的雷射光源。
最後，實驗對具有二氧化鉿和二氧化矽鍍膜的熔融石英樣品進行了532奈米與1064奈米的雷射誘導損傷閾值測試。實驗結果該樣品在532奈米與1064奈米的測試中分別具有52 J/cm²與81 J/cm² 的損傷閾值。在以顯微鏡觀測測試樣品時，我們觀察到三種不同型態的雷射誘導損傷。本論文基於測得的損傷閾值與損傷型態討論了相關的損傷產生機制與光學鍍膜品質。

This study focuses on a 1064-nm Nd:YAG-based laser system for Laser-Induced Damage Threshold (LIDT) testing of optical coatings. The laser system comprises a 10-ns pulse-width passive Q-switched seed laser and a two-stage laser amplifier system. The amplifier system consists of a diode-pumped pre-amplifier and an LED-pumped 4-pass power amplifier, both employing Nd:YAG as the laser gain medium. The laser system produces laser pulses up to 100 mJ at 1064 nm. To have LIDT test at different wavelengths, the system further generates 532-nm and 266-nm lasers via Second Harmonic Generation (SHG) and Fourth Harmonic Generation (FHG), and mid-infrared pulses through Optical Parametric Generation (OPG). The SHG is achieved by injecting the 1064-nm laser into an 8×8×6 mm Potassium Titanyl Phosphate (KTP) crystal, and the FHG is achieved by injection the SHG laser at 532 nm into a 7×7×6 mm Beta Barium Borate (BBO) crystal. The OPG is performed using a 5-cm-long Periodically-Poled Lithium Niobate (PPLN) crystal with input from the 1064 nm laser. By using the laser-amplifier system and its wavelength converters, we performed LIDT tests on a Hafnium Dioxide (HfO₂)/Silicon Dioxide (SiO₂) coated fused silica sample to show damage thresholds of 52 J/cm² at 532 nm and 81 J/cm² at 1064 nm, with different damage types observed and analyzed.

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