採用時域擬譜法模擬分析不完全光學相位共軛使光聚焦在混濁介質之可行性

PSTD Simulation Analysis of the Feasibility to Focus Light through Turbid Media via Incomplete Optical Phase Conjugation

周沛霖(Pei-Lin Chou)

指導教授 ： 曾雪峰

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202101319

摘要

由於生物組織結構上的不均勻性，使得光在傳播過程中經歷多次的散射，導致難以有效將能量傳遞至生物體內，進而阻礙生醫光學技術上的發展。根據非線性光學中的相位共軛特性，可以產生一個與原入射光場互為共軛的波，此共軛波將循原路回溯，進而消除多重散射效應。本論文採用二維的時域擬譜法（pseudospectral time-domain, PSTD）來模擬生物組織等散射介質中的光學相位共軛（optical phase conjugation）現象。藉由馬克士威方程組數值解，我們嘗試模擬分析僅使用部分散射光場資訊使光聚焦在混濁介質之可行性，並進一步研究可能影響光聚焦的各種因素。此研究結果將有助於了解光在生物組織結構中的傳播與聚焦特性，進而擴展生醫光學的應用深度。

關鍵字

時域擬譜法 ； 光學相位共軛 ； 散射 ； 光聚焦

並列摘要

We employ the pseudospectral time-domain (PSTD) technique to model the optical phase conjugation (OPC) phenomenon of light propagation through scattering media such as biological tissue. By means of numerical solutions of Maxwell’s equations, accurate phasor information of the scattered light field can be obtained precisely to explore the feasibility of using only the phase information and constant amplitude to achieve turbidity suppression and to further investigate various factors that may contribute to this phenomenon. The reported simulation findings may provide essential information in the research of focusing light through scattering media with phase-only information.

並列關鍵字

pseudospectral time-domain (PSTD) ； optical phase conjugation (OPC) ； scattering ； light focusing

參考文獻

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