電光高分子表面電漿共振光調制器之研究

Study on Electro-optic Polymer SPR Light Modulator

童聿銓(Yu-chuan Tung)

指導教授 ： 郭文凱

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2008年)

摘要

在論文中，我們應用電光高分子材料於表面電漿共振結構來製作光調變器。這種高分子電光調變器，係將高分子材料塗佈在金屬層上，經過電場極化後具有電光效應，藉由稜鏡耦合入射光至金屬層，在特定入射角時，電光高分子與金屬膜之間產生表面電漿共振波，透過外加電壓來調變電光高分子的折射率，以改變共振耦合條件，可調變反射光的相位延遲，再結合橢圓偏光術組態來將此相位延遲轉成光強度之變化。我們使用含偶氮聚合高分子材料來製作電光高分子薄膜，使用接觸式極化系統極化高分子後，電光高分子的電光係數r33約為10 pm/V。在電光高分子膜層厚度最佳化下，使用峰對峰值為20.3 V，頻率為1.17 KHz的弦波訊號直接調變此電光調變器可得0.03%的調變量。

關鍵字

電光高分子 ； 光調制器 ； 表面電漿共振

並列摘要

In this dissertation, we apply electro-optic (EO) polymer material to the surface plasmon resonance structure to implement a light modulator. In this device, the polymer material is spin-coated on a metal layer and the poling process is applied to enable the polymer to have EO effect. A prism is used to couple the incident light to excite the surface plasmon wave on the interface between the metal and the polymer layer. Applying voltage on the EO polymer film to alter its reflective index can modify the wave coupling condition and change the retardation of the reflective light. This retardation change can be converted to light intensity difference using optical ellipsometry configuration. DR1-PMMA polymer material is used in our device. We use contact poling method and the poled polymer exhibits an EO coefficient r33 of 10 pm/V. With the optimization of the thickness of EO film, the modulation signal voltage is 20.3 V peak-to-peak and frequency is 1.17 KHz, the modulation index is 0.03%.

並列關鍵字

electro-optical polymer ； light modulator ； surface plasmon resonance

參考文獻

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