基于GRIN透镜的内窥OCT探头设计

Design of endoscopic OCT probe based on GRIN lens

提出一种用于在体活检的光谱OCT内窥探头的设计方案,能够实现对生物组织器官深度信息的在体内快速动态实时扫描成像,在临床医学领域具有广阔的应用前景。文中对探头的设计进行了理论分析,对探头的加工和测试进行了系统的阐述。针对传统的GRIN探头设计,本文探头的设计提高了光学质量和机械健壮性。对于OCT探头的成像质量依赖于单模光纤和GRIN透镜之间的距离(玻璃垫片长度),进行了建模和验证。实验得出将玻璃垫片长度控制在0.2 mm左右,探头可以达到2 cm左右的工作距离,工作距离范围内探头的远场光束发散角为0.0175°。

A design of OCT endoscopic probe for tissue biopsy is proposed,and this probe can be used for real time imaging of tissue profile based on tissue depth information,so it has broad prospect in clinical application.The design of probe was theoretically analyzed,and then the process and measurement of the probe were elaborated in de-tail.Compared with the traditional probe,the proposed probe can improve the optical quality and machine robust.The principle that the image quality depends on the distance between single mode fiber and GRIN lens was modeled and verified.The experimental results show that,when the length of glass spacer is about 0.2 mm,the working distance of the probe reaches about 2 cm and its divergence angle of far field is 0.01 75°.