摘 要
光纖具有高頻寬、快傳輸速度及無電磁干擾等特性，因此在近10年來，它開始在全世界通訊領域中被大量地使用。另一方面，在某些特殊環境之條件中如核電廠、太空衛星…等高輻射區域，在使用光傳輸裝置日漸增多已成為必然之趨勢，於是在全世界許多相關機構如歐洲太空總署(ESA) 、美國太空總署(NASA)及美國戈大航太中心(Goddard Space Flight Center/ Swales Aerospace)等，皆先後對光通訊元件如光分歧器(Splitter) 、波長分工器(Wave Length Multiplexer)光纖、光纜、連接器跳線…等進行一連串之實驗，以掌握這些元件在輻射照射下光學特性之影響。本研究之主要目的在於實際上以美國康寧公司之單模(Single Mode)及多模光纖進行60Co之輻射照射，以線上即時偵測之方式探索光纖在輻射場中之輻射誘導衰減情形，以及離開輻射場後之恢復情形。由於測試條件不同，本研究同時比較以目前光通訊領域常用之單模(SM)光纖在1310nm及1550nm波長，以及多模(MM) 光纖在850nm及1310nm波長範圍，實際以OTDR測量其衰減變化與國外類似研究結果比較，研究結果發現光纖在3KGy(Si)之照射過程中，其光衰減值明顯上升。多模62.5/125光纖絲使用在850nm波長，雖其衰減值不高，但其OTDR波形顯示已充滿雜訊(Noise)不堪使用。另外在退火方面，實驗數據顯示35℃左右是單模光纖絲之適當退火溫度.

ABSTRACT
Optical fiber possesses the characteristics of broader band, faster transmission speed and no electronic magnetic interference etc., which has been broadly applied in the field of telecommunication in the last decade. On the other hand, in some specific high radiation zones such as nuclear power plant, space satellite etc., the increasing application of optical transmission facilities has been become a consequential trend.

As far as radiation effects being concerned the related organizations such as European Space Agency (ESA), National Aeronautics and Space Administration (NASA), Goddard Space Flight Center/Swales Aerospace are all proceeding a series of tests on optical communication parts such as splitter, wave length multiplexer, optical fiber, OFC, connector, patch cord…etc.

For the purpose of controlling their characteristics under radiation field, the major purpose of this research is testing Corning company’s single mode & multimode optical fiber by means of 60Co irradiation. In the mean time, we were measuring induced attenuation by on-line monitoring, and studying the situation after irradiation. This project is also comparing with the results that have been achieved by the other nations. Besides, we were measuring attenuation by means of OTDR (Optical Time Domain Reflectometers) on single mode optical fiber applied in 1310nm & 1550nm wave length and multimode optical fiber applied in 850nm & 1310nm wave length. This test result showing that the attenuation is remarkably increasing during 3kGy(Si) irradiation. Multimode optical fiber applied in 850nm wave length is not available as its spectrum of OTDR is full of noise although its attenuation was not high. As to annealing, testing results were not good at full temperature range but just appropriate at the temperature of 35℃.

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