光學同調斷層掃描技術(Optical Coherence Tomography ,OCT),OCT主要分成時域OCT(Time-Domain OCT)與頻域OCT(Frequency-Domain OCT),主要差別在於TDOCT必須手動或是使用電腦控制平台讓樣品端與參考端光程差等於零,而FDOCT不需要做連續性移動,只要將光譜儀所接收的數據經由電腦程式Matlab做傅立葉轉換(Fourier Transform)就可以達到我們想要的樣品資料。 在本論文中,我們提出了一個改良的共路徑頻域OCT系統架構,可以獲得兩組相位移的正交極化光,利用相位移演算法消除不必要的訊號達到兩倍的量測範圍,並且改良光路上的設計,使我們可以量測出未知樣品的厚度以及誤差分析。
Optical Coherence Tomography (OCT) is widely applied to industrial measurement and biomedicine for development imaging, divided into two scanning modes of time domain OCT and frequency domain OCT. FDOCT used Fourier transform by Matlab program can obtain sample data. We propose an improved Common-path FDOCT structure based on the two phase-shifting signals and two orthogonally polarized lights. This experimental setup can eliminate unnecessary noise terms and doubling the measurement range. In this study, we can measure the thickness of unknown sample and obtain the error analysis of the proposed method.