University of Montreal, Institute of Biomedical Engineering, Montreal, Quebec, Canada.
Maisonneuve-Rosemont Hospital Research Centre, Montreal, Quebec, Canada.
J Biomed Opt. 2019 Nov;25(3):1-5. doi: 10.1117/1.JBO.25.3.032006.
We introduced and validated a method to miniaturize graded-index (GRIN) fiber-based optical coherence tomography (OCT) probes down to 70 μm in diameter. The probes consist in an assembly of single-mode (SM), coreless (CL), and graded-index (GRIN) fibers. We opted for a probe design enabling controlled size reduction by hydrogen fluoride etching. The fabrication approach prevents nonuniform etching for both the GRIN and SM fiber components, while it requires no probe polishing postetching. We found that the miniaturized probes present insignificant loss of sensitivity (∼1 dB) compared to their thicker (125 μm) counterparts. We also showed that their focusing capabilities remain tunable and highly predictable. The fabrication process is simple and can be carried out by using inexpensive telecom equipment. Both the fabrication process and the developed probes can benefit the prototyping of minimally invasive endoscopic tools.
我们介绍并验证了一种将渐变折射率（GRIN）光纤基光学相干断层扫描（OCT）探头缩小到 70μm 直径的方法。这些探头由单模（SM）、无芯（CL）和渐变折射率（GRIN）光纤组成。我们选择了一种通过氢氟酸刻蚀实现可控尺寸减小的探头设计。该制造方法可防止 GRIN 和 SM 光纤组件的不均匀蚀刻，并且不需要在刻蚀后对探头进行抛光。我们发现，与较厚的（125μm）探头相比，微型探头的灵敏度损失可忽略不计（约 1dB）。我们还表明，它们的聚焦能力仍然可调且高度可预测。制造工艺简单，可使用廉价的电信设备进行。制造工艺和开发的探头都可以受益于微创内窥镜工具的原型制作。
