Yao Jianing, Meemon Panomsak, Ponting Michael, Rolland Jannick P
Opt Express. 2015 Mar 9;23(5):6428-43. doi: 10.1364/OE.23.006428.
The fabrication of high-performance spherical gradient refractive index (S-GRIN) optics requires nondestructive metrology techniques to inspect the samples. We have developed an angular-scan, swept-source-based, Fourier-domain optical coherence tomography (OCT) system centered at 1318 nm with 5 mm imaging depth capable of 180° polar scan and 360° azimuthal scan to investigate polymeric S-GRIN preforms. We demonstrate a method that enables simultaneous mapping of the group optical thickness, physical thickness, the radially-averaged group refractive index, and the transmitted wavefront of the S-GRIN preforms. The angular scan OCT imaging and metrology enables direct visualization, molding uniformity characterization, and optical property evaluations of the preforms. The results on two generations of S-GRIN preforms are discussed that showcase the evolution of the manufacturing process in response to the OCT metrology feedback.
高性能球面梯度折射率（S-GRIN）光学器件的制造需要无损计量技术来检测样品。我们开发了一种基于扫频源的傅里叶域光学相干断层扫描（OCT）系统，该系统以1318 nm为中心波长，成像深度为5 mm，能够进行180°极坐标扫描和360°方位角扫描，用于研究聚合物S-GRIN预制棒。我们展示了一种方法，该方法能够同时绘制S-GRIN预制棒的群光学厚度、物理厚度、径向平均群折射率和透射波前。角度扫描OCT成像和计量能够对预制棒进行直接可视化、成型均匀性表征和光学性能评估。讨论了两代S-GRIN预制棒的结果，展示了制造工艺如何根据OCT计量反馈进行演变。
