使用向列型液晶於產生干涉條紋之研究

The Study of Interference Patterns Formed by the Nematic Liquid Crystals

柯易明(Yi-Ming Ke)

指導教授 ： 劉育松

國立虎尾科技大學/電機資訊學院/電子工程系碩士班/碩士(2014年)

摘要

本論文使用向列型液晶以產生干涉條紋，實驗中調整液晶之外加交流電壓及頻率，可達到干涉條紋週期改變及干涉條紋平移之效果。
我們模擬液晶分子在不同電壓下之角度分布，並計算同調光源之異常波及尋常波行經液晶後產生不同相位差分布而形成干涉條紋，以此理論計算來擬合並解釋條紋週期改變及條紋位移的現象，發現理論計算結果與實驗結果呈高度相關性。
在實驗中，我們也發現了交流電頻率也會對干涉條紋產生寬度及位移的影響，也進行了頻率影響向列型液晶的分析及探討。

關鍵字

干涉條紋 ； 楔型液晶樣品 ； 交流電頻率 ； 向列型液晶

並列摘要

In this paper, the interference patterns were generated by the nematic liquid crystals. In the experiment, the voltage values and frequencies of the alternating current (AC) voltages applied on the liquid crystals were adjusted to change the periods of the interference patterns and to translate these patterns.
We simulated the angular distribution of the liquid crystal molecules under different voltages. The extraordinary and ordinary coherent waves passing through the liquid crystals acquired various phase difference distribution to form interference patterns. This theoretical calculation was used to fit and explain the phenomena of the changing of the periods and the translating of the interference patterns. The theoretical and experimental results were highly agreed.
In the experiment we also found the frequencies of the AC voltages influenced the periods and translation of interference patterns. An investigation and discussion toward the effect of the frequency on the liquid crystals were also made.

並列關鍵字

interference patterns ； wedge-shaped liquid crystal sample ； frequency ； nematic liquid crystals

參考文獻

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