本論文主要研究內容為醫用近紅外光擴散斷層掃描之光電量測系統設計與驗証。此系統採用單一旋轉光源及感測器之方式，量測於實驗假體外圍經擴散後之光源強度，以提供擴散光學斷層掃描技術之後續影像重建計算所使用。相對於其他多通道固定角度量測之設計方式，此系統具有實際使用上之許多優點，如較少之硬體設備及依需要調整量測點數等。研究中使用高散射微型球、血紅素粉末調製成不同濃度之溶液，以及均質、非均質組成成分之實驗假體作為系統量測驗證對象。其他影響量測之因素與正規化程序亦於文中提出並討論，例如空氣層隙、燒杯介質及輸入光功率大小等因素。最後的量測結果經修正後之皮爾蘭伯特定律的模擬，驗證此系統確實可以量測出不同光學特性物質;並將16次掃描結果以背投影方式重建其相對光衰減係數分佈圖，其結果與經由反算所獲得之重建影像相近。 This thesis describes the design, implementation and verification of the near infra-red (NIR) diffuse optical tomography electro-optical measuring system which uses single rotating source/detector scanning mechanism and is suited for the purpose of medical diagnostics. The fibers connected to the source and detector are driven by stepping motors to achieve scanning operation. Therefore, the measuring system based on rotational motion possesses a high degree of spatial flexibility. The data acquisition system is based on continued-intensity scheme to acquire output radiance signals. System verification is performed using both homogeneous and heterogeneous phantoms. Judging form the measured results, this measuring system is able to differentiate the optical properties which are different in the homogeneous and heterogeneous phantoms. Normalization processes such as input power are also presented. Moreover, both simulated radiance power and reconstructed optical-property image are performed using the modified Beer-Lambert law and back projection imaging method, respectively. The obtained image is comparable to the reconstructed image using the finite element inverse computation scheme.
