以時域有限差分法模擬光學同調斷層掃描

Abstract

摘要 光學相干層析技術（ OCT ）是一種顯微鏡方法，現在已經獲得了普及。這是一個光學信號採集和處理方法，使一個非常高品質，高分辨率（微米級） ，並有能力生產三維圖像內光散射媒體得到的。華僑城被廣泛應用於醫學領域特別是在觀測的生物組織，但它也可用於光子的高精度測量。一些華僑城優點是高分辨 率和高還深穿透。 基本華僑城是干涉。我們使用低相干光作為光源。在這裡，我們嘗試診斷鑑於這是來自樣品臂的光從參考臂用的原則，邁克耳孫干涉儀。相結合的反射光從樣品臂和參考臂將產生干涉模式只有輕武器都走過了同樣優秀的光學距離。這意味著雙方將有相同的光學路徑長度。 真 正的華僑城模擬，但是，有一個限制的條件，地點和材料，目前正在觀察。為了簡化這個問題，我們嘗試以模擬10月利用有限差分時域（ FDTD法）方法。這種模擬方法使我們能夠建立一個範例，我們需要的材料，並提出了假設情況，適合觀測的材料是很難在現實世界中。在此模擬，我們建立了一 個樣本材料，然後嘗試建造一個代表性的形象材料。若干假設是用於這一模擬實現一個更好的結果的目的。

Abstract Optical Coherence Tomography (OCT) is a kind of microscopy method that has gained popularity nowadays. It is an optical signal acquisition and processing method that allowed an extremely high-quality, high resolution (micrometer scale), and ability to produce a three-dimensional images from within optical scattering media to be obtained. OCT is widely used in medical field especially in observing the biological tissue, although it is also can be used in photonics for a high precision measurement. Some of OCT advantages are high resolution and also deep penetration. The basic of OCT is interferometry. We use a low coherence light as the light source. Here we try to diagnose the light that is coming from the sample arm with the light from reference arm by using the principle of Michelson interferometer. The combination of reflected light from the sample arm and the reference arm will give rise to an interference pattern only if light from both arms have travelled in the same optical distance. It means that both will have the same optical path length.

The real OCT simulation, however, has a limitation from the condition of the place and the material that is being observed. To simplify this problem, we try to simulate the OCT by using the Finite-Difference Time-Domain (FDTD) method. This simulation method allow us to construct a sample material that we need and made a scenario that is suitable for observing the material that is difficult in the real world. In this simulation, we build a sample material and then try to construct a representation of image of the material. Several assumptions are used for this simulation to achieve a better result in the end. Contents