本論文的研究主題是探討Morpho 蝴蝶翅膀的反射特性，此種蝴蝶在任意角度的觀測下，皆呈現藍色金屬光澤，且顏色的產生並不是來自於色素，而是結構的反射所造成。在過去的研究中用很多種理論來解釋此現象，在此我們使用平面波展開法(plane wave expansion method, PWE)來研究Morpho蝴蝶翅膀的反射現象，目的是找出在不同角度下有相同的帶隙分佈，為了達到此目的，我們改變蝴蝶結構的變數，並使用不同的判斷參數來討論每一個帶隙的變化。在TE偏振下的紅外線波長區域找到最接近理想的帶隙形態，當角度範圍為0°~90°，其頻寬比(bandwidth ratio=Δf / fcenter)為0.0267。最後，以最接近理想帶隙的結構變數為基準，並改變結構變數W1和W2，發現當W1愈小時，角度範圍變大的程度增加，且由最佳的結構形狀推論出造成大範圍角度的原因是矩形結構所產生的結果。This thesis studies the reflection characteristics of Morpho butterfly wing. The butterfly can produce metallic blue from any observation viewpoint. The coloration originates from the sub-micron scale structure. We adopt the plane wave expansion method to study the phenomenon. The purpose is to look for the similar photonic band gap for different propagation directions. In order to achieve the purpose, we change the structural variables of the butterfly. It is found that in the TE mode, we can observe a flat wide-angle band gap. The angle range of the band gap is from zero degree to ninety degree. The corresponding bandwidth ratio is 0.0267. Finally, when the structure parameter W1 becomes small, the angle range of the reflection increases. It shows that the wide-angle range reflection is due to the rectangle structures in Morpho butterfly.
