高密度分波多工器(DWDM)濾光片的應力與溫飄特性研究

Research of the Stresses and Thermal Stabilities in the Dense-Wavelength-Division-Multiplexing (DWDM) Filters

郭倩丞(Chien-Cheng Kuo)

指導教授 ： 李正中

國立中央大學/理學院/光電科學研究所/博士(2007年)

摘要

高密度分波多工器(DWDM)濾光片已廣泛應用於光纖通訊的系統之中，由於其層數多膜層厚，所造成的應力比一般的鍍膜產品大，且為提高光纖通訊系統之可靠度，溫度對於其光學穩定性的影響就顯得越來越重要，符合國際規範的DWDM100GHz濾光片，其溫飄值必須要小於1pm/℃。Takashashi[3]首先為溫飄分析提供理論模型，但由於光纖通訊系統的要求越來越嚴格，使得膜層數增加，造成的應力變化越來越大，必須考慮應力改變對光學厚度的影響，本論文提出理論公式，用以模擬應力及溫度對窄帶濾光片之中心波長的影響，並了解基板的熱膨脹係數，薄膜的折射率、楊氏模數、帕松比、熱膨脹係數及歸一化折射率溫度係數對其影響的程度，並輔以實際100GHz濾光片產品的結果比較，對於應力及溫度造成光學特性上的變化有更深層的了解，並可應用在厚膜或是薄基板的產品中，預測應力及溫度所造成光學特性上的變化。

關鍵字

高密度分波多工器濾光片 ； 應力 ； 溫飄

並列摘要

Dense-wavelength-division-multiplexing (DWDM)filter is a very important component for optical fiber communication. DWDM filter fabricated by thin film coating is a type of narrow bandpass filter (NBPF). The stability and reliability of these applications are depended on the mechanical properties of the stresses, the Young’s modulus, Poisson ratio, Temperature coefficient of refractive index and the Coefficients of Thermal Expansion (CTE) of the thin films and their substrates. However if the substrate thicknesses were changed, the mechanical and optical properties of the thin films are also changed. Takashashi is first one to offer the theory model for the temperature stability of the center wavelength (TSCW). But the request for the optic fiber communication system is more difficult, the thickness of the DWDM filters increase. We must consider the effect of the stress changes on the DWDM filters.
In this paper we provide new formula to analyze the influence of the stresses and thermal stabilities in the Dense-Wavelength-Division-Multiplexing (DWDM) filters and compare the influence of Coefficients of Thermal Expansion (CTE) of the substrate, the Young’s modulus of thin film, Poisson ratio of thin film, Temperature coefficient of refractive index of thin film and the Coefficients of Thermal Expansion (CTE) of the thin films in real 100GHz filter result. We have more understanding to the influence of stress and temperature of the DWDM filters and can apply to the filters of thick thin film thickness or thin substrate. We can predict the change on the optics characteristic that the stress and temperature cause.

並列關鍵字

DWDM ； stress ； temperature stability of the center wavelength (

參考文獻

[9] 朱正煒, “DWDM干涉濾光片之設計及製作”,光學工程第六十八期, 88年12月, P.40-45.

[1] J. Minowa and Y. Fujii, “Subnanometer bandwidth interference filter for optical fiber communication systems”, Appl. Opt., 27, pp.1385-1386, 1988.

[2] H. Takashashi, “Temperature stability of thin-film narrow-bandpass filters produced by ion-assisted deposition”, SPIE Vol. 2253, pp. 1343-1353, 1994.

[3] H. Takashashi, “Temperature stability of thin-film narrow-bandpass filters produced by ion-assisted deposition”, Appl. Opt., 34, pp. 667-675, 1995.

[4] A. Zoller, R. Gotzelmann, K. Matl, and D. Cushing, “Temperature-stable bandpass filters deposited with plasma ion-assisted deposition”, Appl. Opt., 35, pp. 5609-5612, 1996.