基于GRIN镜头的小型OCT探头的数值分析

摘要

Numerical simulation technology was investigated by using the optical software GLAD to design Gradient Index(GRIN)lens based miniature probes for imaging of Optical Coherence Tomography(OCT).Firstly,the basic features of the GRIN lens were overviewed,and design methods for GRIN lens based optical probes were discussed.Then,the probe model consisting of a single mode fiber,a glass rod spacer and a GRIN lens were simulated.The simulating results show that the numerical simulation technique using GLAD can provide an intuitive and effective method for design of miniaturized probes and verification of their optical performance.In addition,the spacer can improve the optical properties of the GRIN lens based optical probes for there exists a suitable range of the spacer lengths in the glass rod.It shows that the working distance of the probe will be greater than 1.0 mm and the focus spot size less than 40 μm when the constant length of GRIN lens is to be 0.1 mm and the spacer length range from 0.8 to 1.1 mm.%利用光学软件GLAD的数值仿真技术设计了用于光学相干层析技术成像的基于梯度折射率(GRIN)镜头的小型化探头.首先,简述了梯度折射率镜头的基本特性,讨论了基于梯度折射率镜头的光学探头的设计方法；然后,对由单模光纤、玻璃棒隔片和梯度折射率镜头构成的探头模型进行了仿真.结果显示,利用GLAD的数值仿真技术为小型化探头的设计及其光学性能的验证提供了一种直观而有效的方法.另外,玻璃棒隔片存在一个适当的长度范围,可以改善设计的光学探头的传光性能.在所给仿真条件下,如设定梯度折射率镜头长0.1 mm、玻璃棒隔片长度为0.8～1.1 mm,则探头的工作距离将超过1.0 mm,而聚焦光斑的尺寸＜40 μm.