光學同調斷層掃描儀是一種新穎的非侵入式醫學影像技術，其縱向解析度受光源的中心波長與頻寬所影響。本實驗室所研製生長的摻鉻鎂橄欖石晶體光纖擁有寬頻的自發輻射頻譜與適當波長，若做為光學同調掃描系統光源，可增進其縱向解析度近微米級，能夠掃瞄到細胞組織間細微結構之影像，故對於早期疾病檢查與組織結構之探討與研究有相當大之應用價值。

本論文研究摻鉻鎂橄欖石晶體光纖的製作與特性量測。藉由雷射加熱基座生長法，我們生長出不同直徑的摻鉻鎂橄欖石晶體光纖與玻璃纖衣包覆的單纖衣晶體光纖，纖核直徑為70 μm。藉由電子微探儀量測其鉻離子平均濃度為0.011 Wt.%，纖核折射率經共焦顯微鏡量測為1.635。以長度為22 mm的單纖衣摻鉻鎂橄欖石晶體光纖利用半導體雷射(915±10 nm)為幫浦光，成功研製波峰1107 nm，3 dB頻寬為168 nm的超頻寬自發輻射放大光源，初期功率可獲得25 μW當幫浦功率為1.12 W，以其用作光學同調斷層掃描儀，其縱向解析度可達約3 μm。

Optical coherence tomography (OCT) is a novel non-invasive medical tomography technology. Its axial resolution is determined by the center wavelength and bandwidth of the light source. Our proprietary Cr:forsterite single-clad crystal fiber has broad bandwidth and proper center wavelength. If applied as an OCT light source, micrometer-level resolution may likely be achieved. It is very useful for imaging fine structures of cells and tissues, and for early diagnostics of disease.

In this thesis, research work was conducted on fabrication and characterization of Cr:forsterite crystal fibers. By means of laser heated pedestal growth (LHPG) method, we have successfully developed Cr:forsterite single crystal fibers of various diameters, and a glass-clad crystal fiber with a core diameter of 70 μm. By using electron probe micro-analyzer (EPMA), an average chromium concentration of 0.011 Wt.% was measured. The refractive index of the core was measured to be 1.635 with confocal microscope. In addition, we have successfully demonstrated a diode-laser (915±10 nm) pumped Cr:forsterite-crystal-fiber amplified-spontaneous-emission (ASE) light source. Using a 22 mm-long fiber, a 3-dB bandwidth of 168 nm, a peak wavelength of 1107 nm, and a CW power of 25 μW were obtained under a pump power of 1.12 W in early results.If used as OCT light source, would be about 3 μm.

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