請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/64570
標題: | 適用太空環境的高效能光纖陀螺儀之抗輻超螢光光纖光源 Radiation Tolerant Superfluorescent Fiber Sources for High Performance Fiber Optic Gyroscopes in Space Environment |
作者: | Tz-Shiuan Peng 彭子軒 |
指導教授: | 王倫 |
關鍵字: | 超螢光光纖光源,抗輻技術,光纖陀螺儀,太空光電,光退火, superfluorescent fiber sourece,radiation hardening,fiber optic gyroscope,space photonics, |
出版年 : | 2012 |
學位: | 博士 |
摘要: | 本博士論文解決了高性能光纖陀螺儀在太空應用中最重要的問題,論文中報告了摻鉺光纖的輻射效應,提出了光退火法用以快速回復摻鉺光纖的輻射損耗,也提出了反射率調整技術用以完全消除輻射造成超螢光光纖光源的平均波長漂移,結合這些方法,本論文提出的抗輻超螢光光纖光源可幫助高性能光纖陀螺儀擁有不受輻射影響的效能。
一般光纖的輻射損耗來自輻射游離的電子或電洞被陷獲在光纖纖核中玻璃結構的點缺陷裡,摻雜元素會使得光纖的輻射敏感度上升,因此摻鉺光纖的輻射敏感度較純石英纖核光纖來得高,摻鉺光纖的輻射損耗主要來自共摻雜元素,例如:鋁與鍺,輻射損耗對輻射劑量關係可用冪次函數擬合得很好,本論文找到輻射敏感度對鋁濃度有線性關係,其斜率為0.24 dB/m/krad/mole%,實驗的鋁濃度範圍為1.1 M%至4.2 M%。 波長532 nm光退火有非常優良的退火效率,摻鉺光纖在波長900 nm到1700 nm的輻射損耗可被完全恢復,從模擬計算的結果中推測在太空中摻鉺光纖的輻射損耗可因此減低至0.002 dB/m。另一方面,反射率調整技術可使得超螢光光纖光源在輻射環境中維持相同的平均波長,而且有著34 nm寬的頻寬,結合上述兩者技術,此抗輻的超螢光光纖光源可以保持穩定的平均波長以及大於40 mW的高輸出功率直到累積輻射劑量為200 krad,此效能超越以往文獻的結果,且優於超螢光二極體。本論文預期使用提出的抗輻超螢光光纖光源,即可實現抗輻的導航級光纖陀螺儀,更近一步地,若光纖的輻射損耗是可用修正的冪次函數來外插估計太空輻射劑量時的輻射損耗,那麼抗輻的高性能光纖陀螺儀應是可以實現的。 This dissertation solves the most important problem for a high performance interferometric fiber optic gyroscope (IFOG) in space applications. It reports the radiation effects of erbium doped fibers (EDFs), proposes the photo-annealing method to rapidly recover the radiation induced attenuation (RIA) of EDFs, and proposes the reflectivity tuning technique to totally eliminate the radiation-induced mean-wavelength drifts of the superfluorescent fiber sources (SFSs), thus a high performance, radiation hardened IFOG can be realized in the future. The RIA of an optical fiber results from the radiolytic electrons or holes trapped by defect sites in the glass matrix of the fiber's core. Doping material in the fiber's core always increases the RIA sensitivity of the optical fiber, so an EDF has much higher RIA sensitivity than a pure silica core fiber. The RIA of EDF was mainly due to other dopants, e.g. aluminum and germanium. The RIA dependence on dose was always well fitted by a power law function. A linear dependence of RIA sensitivity on the Al3+ concentration was found and it had a slope of 0.24 dB/m/krad/mole% when the Al3+ concentration was from 1.1 M% to 4.2 M%. The 532-nm photo-annealing showed excellent annealing efficiency, and it could nearly diminish the RIA of EDFs in the wavelength range from 900 nm to 1700 nm. The simulation study estimated the RIA of irradiated EDFs in space could be as low as 0.002 dB/m by using the 532-nm photo-annealing technique. In addition, by employing reflectivity tuning method, the SFS could maintain the same mean-wavelength during irradiation, and have a broad linewidth of 34 nm. Combining these two techniques in an SFS, even under irradiation of 200 krad, the mean-wavelength could be stabilized and the output power could be higher than 40 mW. Such a radiation-tolerant SFS had improved performance and was better than those in the previous reports. In addition, the performance of this radiation-tolerant SFS was also better than that of superluminescent diode (SLD). A radiation-hardened IFOG with navigation grade is possible by using the proposed radiation-tolerant SFS. Furthermore, if the dependence of coil's RIA on dose rate could be well extrapolated by using the modified power law for the low dose rate in space, a radiation-hardened IFOG with high performance could be realized. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/64570 |
全文授權: | 有償授權 |
顯示於系所單位: | 光電工程學研究所 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-101-1.pdf 目前未授權公開取用 | 5.11 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。