極化式編碼於孔徑函數上之應用

Abstract

繞射理論可依據觀測材料的特性與觀測維度的大小，分成將電磁場視為純量的純量繞射理論與實際考量各點邊界條件解出該點電磁場，計算上較為複雜的向量繞射。以往，於空間解析度低的情況下(低數值孔徑)，採用純量繞射已可得到不錯的近似解；然而，由於科技的日益進步，空間解析度也日漸增加(高數值孔徑)，光的向量特性必須加以考量，此時純量繞射已不再適用，必須採用向量繞射來解釋。 因此，於此篇論文中，首先會針對各種極化於聚焦平面上的場形分布做討論，指出不同極化於高數值孔徑的系統下，聚焦場形之各種特性。接著，考量到極化於日後顯微系統的影響，我們利用不同或高階數的非勻質極化於孔徑上的分布，來達到拓展景深的應用；之後再藉由創造出的多波長非勻質極化光，將其應用至表面電漿領域，建立一個即時之感測系統，並提出一金屬-絕緣層-金屬的結構，來完善此感測系統。

In the diffraction theory, scalar diffraction theory is based on specific material condition or observed with low NA system, the fields are treated as the scalar components to obtain a good approximation by relatively simple mathematics formula. However, while the technique was fast developed, the dimension and materials is more and more small and variety, respectively. Therefore, the vetorial properties of light are no longer neglected in the discussion of polarization. In this thesis, first part was addressed about the effect of polarization in different numerical apertures, the influence of polarization is more distinct as numerical aperture increases. The second part was addressed to discuss extending depth of focus by the synthesis of polarizations. The third part is to build up a polychromatic SPR sensor system utilized excited chromatic radially polarized light and optimize the system by purposed metal-insulator-metal (MIM) structure.