Dissertation/ Thesis
波長可調之近單縱模線型光纖雷射 ; Nearly Single-Longitudinal-Mode Linear-Cavity Tunable Fiber Laser
| العنوان: | 波長可調之近單縱模線型光纖雷射 ; Nearly Single-Longitudinal-Mode Linear-Cavity Tunable Fiber Laser |
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| المؤلفون: | 許偉貞 |
| سنة النشر: | 2012 |
| المجموعة: | National Taiwan University of Science and Technology Repository (NTUSTR) / 台灣科技大學 |
| مصطلحات موضوعية: | 波長可調光纖光柵, 線型共振腔, 法拉第旋轉鏡, 單縱模, 子環形共振腔, 吸收體, linear cavity, wavelength-tunable fiber Bragg grating, Faraday rotator mirror, single-longitudinal-mode, sub-ring cavity, absorber |
| الوصف: | 國立臺灣科技大學光電工程研究所 ; 學位：碩士 ; 指導教授：廖顯奎;陳南光 ; 本論文主旨為架構波長可調之線型近單縱模光纖雷射，利用波長可調光纖光柵搭配兩種反射端面—光循環器與法拉第旋轉鏡，組成線型共振腔。一開始先簡介摻鉺光纖雷射產生原理、波長可調光纖光柵的製作方法及法拉第旋轉鏡的工作原理，接著提及單縱模光纖雷射製作方法，與兩種模態抑制元件，分別為子環形共振腔和摻鉺光纖吸收體。本論文實驗選擇3 m的摻鉺光纖作為增益介質，搭配3埠光循環器或法拉第旋轉鏡，再加入反射波長可調的光纖光柵，製作出可移動14 nm左右的波長可調光纖雷射，此時光訊雜比可達55 dB以上，最大光功率變動量為1.77 dB。其中3埠光循環器是將埠1與埠3對接，使光訊號此時為單方向傳輸，而法拉第旋轉鏡則是使入射訊號光與反射訊號光極化方向正交，以減少干涉現象。後續則加入0.75 m、1 m及1.15 m的子環形共振腔來抑制旁模的產生，其同時加入三個子環形共振腔的光循環器式與法拉第旋轉鏡式，兩者皆可達到近單縱模雷射之效果。另外，加入吸收係數在波長1531 nm為6.24 dB/m的摻鉺光纖吸收體3 m、5 m及7 m，此時模態抑制效果並不顯著，若將子環形共振腔與吸收體一併加入架構中，可達到更佳的模態抑制效果，其法拉第旋轉鏡式可在加入1 m和1.15 m的子環形共振腔及7m的吸收體時，達到近單縱模雷射輸出。光循環器式與法拉第旋轉鏡式皆可在移動波長14 nm左右時，配合子環形共振腔與吸收體同步達到穩定的模態抑制的效果，但由於加入各式模態抑制元件產生的插入損耗，故輸出的雷射光訊雜比降至40 dB左右。未來，此波長可調之單縱模光纖雷射將很有機會廣泛運用於光通訊與光感測等領域。 The thesis investigates nearly single-longitudinal-mode (SLM), linear cavity and wavelength-tunable fiber lasers. Two fiber lasers based on different cavity-end schemes are presented. There are optical circulator (OC) integrated fiber Bragg grating (FBG) type and Faraday rotator mirror (FRM) integrated FBG type. First, we reviewed the theorem of the linear cavity fiber lasers and mentioned prior works done by other group and our lab. Second, we described the SLM design and then we added either sub-ring cavity (SRC) and/or absorber as mode-suppressed element into the fiber laser cavity. In this experiment, we chose 3 m EDFs as the gain medium with OC or FRM to obtain an optical signal-to-noise ratio of more than 55 dB, the largest optical power variation was ±0.9 dB, and the laser span range was 14 nm using tunable FBG. Note that the port 3 was loopback to port 1 of the OC so as unidirectional transmission in the fiber loop may help to partially reduce the mutual injection effect. While the FRM made incident light and reflected light be orthogonal to each other to reduce interference. Furthermore, nearly SLM fiber laser can be achieved by using three SRCs with lengths of 0.75,1 and 1.15 m, respectively, inside the main cavity. On the other hand, used 0.7 m EDF of low absorption coefficient and two ... |
| نوع الوثيقة: | thesis |
| اللغة: | Chinese English |
| Relation: | http://ir.lib.ntust.edu.tw/handle/987654321/32352; http://ir.lib.ntust.edu.tw/bitstream/987654321/32352/-1/index.html |
| الاتاحة: | http://ir.lib.ntust.edu.tw/handle/987654321/32352 http://ir.lib.ntust.edu.tw/bitstream/987654321/32352/-1/index.html |
| رقم الانضمام: | edsbas.EF33D465 |
| قاعدة البيانات: | BASE |
| الوصف غير متاح. |