本論文主要研究矽光子平台技術如何應用於生醫感測中的光學同調斷層掃描，得力於近年來的晶片製程技術發展快速，矽光子受到越來越多關注與進展，使用矽波導當作光的載體，可以良好地實現各種光學元件，例如:定向耦合器、分佈式波導布拉格光柵、陣列式波導光柵等等。隨著實驗室的發展，希望將 光學同調斷層掃描所需之光學元件全部積體化並且在減少架構體積的同時保有影像解析度及清晰度等等。在此論文中著重於積體化光學中的元件對於光學同調斷層掃描影響之研究與探討，解決晶片型光學同調斷層掃描所遇到的問題。利用RSoft和OptSim等光子元件模擬工具模擬不同矽光子元件特性並且可將各個元件組合以探討晶片型光學同調斷層掃描架構。最後利用光子元件工具所產生之光譜結果帶入MATLAB以進行光學同調斷層掃描影像訊號處理。
此論文探 馬赫-曾德爾定向耦合分光能量器的各個參數影響，藉由光學模擬軟體逐步計算及設計優化。在傳統定向耦合中導入馬赫-曾德爾干涉儀使改善原本製程敏感的缺點以及各波長中耦合能量不平衡的問題。
在討論完馬赫-曾德爾定向耦合分光器後將進一步探討如何應用於晶片型光學同調斷層掃描中，在晶片型光學同調斷層掃描當中，所需用到的元件主要有光柵耦合器與能量分光器/結合器。其中光柵耦合器為光纖入光至晶片中的重要元件，能量分光器/結合器為光學同調斷層掃描中重要的元件。我們將使用馬赫-曾德爾定向耦器合來當作晶片型光學同調斷層掃描的能量分光器/結合器。
最後由於光柵耦合器在物理結構上以及理論上的限制，對於波長是敏感的，對於晶片型光學同調斷層掃描將導致縱向解析度降低，在此論文也將馬赫-曾德爾定向耦合進一步推廣為晶格濾波器用以補償晶片型光學同調斷層掃描所使用的光纖光柵耦合器所帶來光源不平坦造成解析度上下降之問題。
在本研究中使用馬赫-曾德爾定向耦器分光器模擬晶片型光學同調斷層掃描，解析度可改善至20.3微米。模擬中使用晶格濾波器補償光纖光柵耦合器，可使解析度進一步下降為13.2 微米。在實際晶片量測中，使用掃頻式光學同調斷層掃描量測架構原本使用光柵耦合器系統的解析度為47.2微米，而經由晶格濾波器補償後可進一步下降至38.25微米。

This thesis mainly studies how silicon photonics platform technology is applied to optical coherence tomography (OCT) in biomedical sensing. Powered by rapid advancements in chip manufacturing technology in recent years, silicon photonics has made enormous progress and garnered increasing attention. Using silicon waveguides as the light carrier allows for excellent realization of various optical components, such as directional couplers, distributed waveguide Bragg grating, array waveguided grating, etc. As the laboratory develops, the goal is to fully integrate all the optical components required for OCT (Optical Coherence Tomography) while reducing the overall system size, maintaining image resolution and clarity, and so on. This thesis focuses on the research and exploration of the integration of optical components and their impact on OCT, aiming to address the issues encountered in chip-based OCT. Different silicon photonics components are simulated using photonics simulation tools such as RSoft and OptSim, and their combinations are analyzed to investigate chip-based OCT architectures. Finally, the spectral results generated by the photonics simulation tools are imported into MATLAB to process OCT image signals further.

This thesis explores the impact of various parameters on the Mach-Zehnder directional coupler (MZDC) for splitting optical power, utilizing optical simulation software for step-by-step calculation and design optimization. Incorporating the Mach-Zehnder interferometer into the traditional directional coupler aims to improve the drawbacks associated with process sensitivity and address the issue of energy coupling imbalance at different wavelengths.

After the MZDC splitter’s study, the applications in chip-based OCT will be further explored. The critical components of the silicon wafer are the grating coupler and the energy splitter/combiner. The grating coupler is crucial for coupling light from the optical fiber into the chip, while the energy splitter/combiner plays a vital role in OCT. We will utilize the MZDC as the energy splitter/combiner in the chip-based OCT setup.

Finally, due to the physical and theoretical limitations of the grating coupler, it is sensitive to the wavelength, which can result in axial resolution reduction for chip-based OCT. In this thesis, the MZDC will also be further extended as a lattice filter to compensate for the resolution degradation caused by the non-uniformity of the light source introduced by the grating coupler used in chip-based OCT.

This study used the MZDC splitter to simulate chip-based OCT, and the resolution was improved to 20.3 micrometers. The simulation using the lattice filter to compensate for the grating coupler could enhance the resolution to 13.2 micrometers. The original resolution with the grating coupler system was 47.2 micrometers in actual chip measurements using the SS-OCT setup. After compensation with the lattice filter, it was further improved to 38.25 micrometers.

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