液滴透鏡曲率調控機制之探討

Study of Profile Manipulation in Liquid Lens

彭孟超(Meng-chao Peng)

指導教授 ： 楊宗勳

國立中央大學/理學院/光電科學研究所/碩士(2008年)

摘要

最古老的液體透鏡製作，可以追溯至17 世紀，發展至今，已有許多不同的製作方式，液壓式、熱效應、介電泳動與目前已有商業產品上市的電濕式液體透鏡，利用電壓的改變，調整透鏡的曲面變化，達到變焦的目的，在這商品不斷地微型化的時代，液體透鏡具有高度的競爭力。
本文利用交流電訊號的電場變動，對液滴的曲率變化做探討，改變峰值電壓與頻率，分析液滴曲率的變化，發現在較低的峰值電壓驅動下，頻率對液滴曲率變化影響較小，高峰值電壓作用下，頻率的改變與液滴曲率變化沒有固定之趨勢，高於3kHz 之後，液滴曲率變化趨於穩定值而不再改變。
此外，交流電的作用使液滴產生振動現象，在不同頻率與峰值電壓作用下，液滴振動模式呈現不同的變化，相同的模式仍有不同的振動形狀，因此在交流電的作用下，可以使液體透鏡展現出更多元的應用。

關鍵字

液體透鏡 ； 液滴 ； 曲率

並列摘要

The fabrication of the oldest liquid lens can be traced to the 17th century.The liquid lens has been developed many kinds of fabrication method as fluidic
pressure, thermal effect, dielectrophoresis and electrowetting so far. Nowadays,the liquid lens based on electrowetting has been commercialization. The applied
electrical voltage can be used to tune the curvature of lens for the tunable-focus.For the time being, the liquid lens has become of very high competition.
In this work, the electric field of AC signal has been explored to investigate the change of curvature of liquid lens. In the analysis, the result liquid curvature is highly dependent on the amplitude and the frequency of the applied electric voltage. It is found that the lower the amplitude of the electric voltage is applied
on the liquid lens, the less the frequency variation on the curvature is. While the higher voltage is applied, the changes of the drop curvature become irregular as
frequency increasing. When the frequency is above 3 kHz, the drop curvature will be almost steady and independent of the applied electric voltage change..
Furthermore, the AC signal induces the drops to vibrate. The vibration modes are also exploited in the amplitude-frequency phase diagram. It is expected to drive the liquid lens by AC signals with much more efficiency.

並列關鍵字

liquid lens ； drops ； curvature

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