探頭式之微型化光學同調斷層掃瞄系統

Miniaturization of an Optical Coherence Tomography System into a Scanning Probe

張正昌(Cheng-Chang Chang)

指導教授 ： 楊志忠

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.02695

摘要

在本論文中，我們整合了一套光學同調斷層掃瞄系統在一個微型探頭內。系統本身採用中心波長1310奈米，具有100奈米頻寬的頻率掃描式光源。在這套系統中使用了高孔徑的光聚焦接頭和一個分光比R/T=60/40的分光稜鏡以提高收光效果。系統本身的縱向解析度為8微米，橫向解析度為20微米。因為光經由分光稜鏡分光後，在參考端及樣品端空氣中之光徑等長，故較傳統的光學同調斷層掃瞄系統在光纖內的色散問題可以得到較大的改善，而光信號的偏極化資訊也可獲得保留。利用這個探頭系統，我們先針對皮膚做活體的掃瞄。根據掃瞄結果發現，我們可清楚分辨皮膚中角質層、表皮以及真皮，這三層主要結構。皮膚影像的掃瞄深度可達1.1公分。皮膚掃瞄影像的尺寸為1.2 x 2.2方釐米，擷取速度則小於一秒。為了測試臨床掃瞄的可行性，我們掃瞄了活體口腔黏膜的影像。在我們的掃瞄過程中，我們針對口腔黏膜中的嘴唇黏膜(包括嘴唇以及口腔內側)做掃瞄。在這些口腔黏膜的掃瞄結果中發現，我們可以觀察到口腔黏膜中上皮層和固有層兩層結構，部分能看到次黏膜的構造。口腔內側影像的掃瞄深度可達1.1公分。

關鍵字

光學同調斷層掃瞄 ； 探頭

並列摘要

In this research, an optical coherence tomography (OCT) system is miniaturization into a probe, which utilizes a swept light source with the central wavelength at 1310 nm and the spectral width at 100 nm. In the OCT system, a high NA focuser with the spot size of 20 μm (lateral resolution) is used. A beamsplitter of reflection/transmission of 60/40 splits the light beam into the reference and sample arms. A silicon wafer coated with gold is used as the reference mirror. Because the configuration of this system is quite simple, the dispersion characteristic is superior to a conventional fiber-based OCT system and the information of polarization can be reserved. The axial resolution of the OCT system is 8 microns. With this hand-held probe, the in vivo scanning results of human skin are first obtained. In such scanning, three major layers, including stratum corneum, epidermis, and dermis, can be clearly identified. The penetration depth of human skin scanning images is 1.1 mm. The image size of human skin scanning of 1.2 mm x 2.2 mm can be completed in less than one second. To test the clinical application, in vivo scanning of oral mucosa is performed. In such scanning, the lining mucosa is scanned. Both in the scanning images of labial mucosa and ventral surface of buccal mucosa, three major layers, including epithelium, lamina propria, and submucosa, can be identified. The scanning depth of labial mucosa is around 1.1 mm.

並列關鍵字

optical coherence tomography ； probe ； OCT

參考文獻

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