本論文提出自製之腐蝕光纖耦合器，並以之與微米小球共振腔作耦合，此系統可應用於光相位延遲、光訊號選取與全光開關等研究。本研究將解析由腐蝕光纖耦合進入微米小球共振腔的耳語廊模場(Whispering gallery mode)與腐蝕光纖中的導波場，藉相位匹配條件與模場重疊度來研究耦合效率與共振腔之品質因子。
實驗中由腐蝕光纖的穿透譜可找出共振腔之共振波長，並分析定義出各共振波長代表之耳語廊模場與品質因子，且歸納出光纖粗細與耦合效率正相關之關係。在實驗中最高耦合效率可達42.07％，高於其他腐蝕光纖最高30％之耦合，單就耦合效率而言，已有長足的突破。

Microsphere resonators have attracted a lot of interest in recent years, due to ultra high quality factor and small modal volume. Numerous methods for coupling energy into the whispering gallery modes of a microsphere have been demonstrated, however most of them are limited by either low coupling efficiency or mechanical instability. In this thesis, an etch-eroded fiber coupler was investigated, and better coupling efficiency and acceptable stability was obtained.
The orders of the WGMs and the quality factors can be determined by analyzing optical transmission spectra and fitting to the theoretical resonant wavelengths. Furthermore, it shows that the smaller the radius of the fiber; the higher the coupling efficiency. In this thesis, the highest coupling efficiency is obtained 42.07％, and the quality factor is ~ 25000.

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