二階光纖光柵之窄光束與光耦合之量測

Measurement of Narrow beam divergence and light coupling for Second Order Fiber Bragg Gratings

吳柏諺(Bo-Yan Wu)

指導教授 ： 孫迺翔

義守大學/智慧科技學院/電機工程學系/碩士(2021年)

摘要

本論文使用Collimator，耦出並量測二階光纖光柵的輻射光，以量測輻射頻譜。我們同時使用步進馬達，利用Collimator耦光，來量測二階光纖光柵的輻射角度，我們發現只有在90°位置有明顯輻射能量，並且有Narrow beam divergence的特性。我們也利用單模光纖、多模光纖與Collimator，將光訊號垂直耦入二階光纖光柵，發現以Collimator耦合效果較佳，最後，我們利用Collimator，將光訊號從45°、60°、90°、120°與135°耦入光纖光柵中，我們發現只有在90°有最佳耦合角度。

關鍵字

光纖布拉格光柵 ； 光纖耦合

並列摘要

In this thesis, radiation power radiated by second-order fiber Bragg gratings (FBGs) are detected by collimators. The stepper motor is used to measure the radiated angles of the second-order FBGs. The maximum radiation power occurs at the normal direction with the property of narrow beam divergence. The light power is coupling into the second-order FBGs by collimators, a mult-mode fiber, and a single mode fiber. The collimator has better coupling efficiency than the others. Finally, light couple into the second-order FBGs with coupling angles of 45°, 60°, 90°, 120°, and 135° by a collimator. The best coupling angle is 90°.

並列關鍵字

fiber Bragg gratings ； fiber coupling ； narrow beam divergence

參考文獻

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