Fiber-Based Polarization Sensitive Optical Coherence Tomography
Department: Electrical and Computer Engineering
Advisor: Chao Zhou
Optical Coherence Tomography (OCT) is a non-invasive, light-based bio imaging device that can depth-resolve tissue structures at micrometer resolutions. A functional extension of this technology, called Polarization Sensitive OCT (PSOCT), illuminates a sample with multiple light polarizations to produce an image that provides additional structural information, including birefringence and depolarization effects. For the better part of the last 20 years, PSOCT has required fine-tuned, free-space optical hardware to produce this effect. However, in recent years, Baumann et. al (2012) and Wang et. al (2014) have proposed a method of PSOCT using spatially multiplexed polarizations to enable the use of an entirely fiber-based system. Fiber-based OCT systems are simpler to produce and maintain, less expensive than free-space systems, and can be used in conjunction with an endoscopic probe. In this project, we have applied the methods proposed by Baumann et. al. and Wang et. al. to build a prototype fiber-based PSOCT system using a 1050 nm wavelength-swept VCSEL laser (Thorlabs). We have achieved polarization multiplexed images, from which we have extracted birefringence information, including phase retardation and degree of polarization uniformity (DOPU). Here, we present polarization sensitive images of a human finger and chicken breast to demonstrate the effectiveness of our system. In the future, we hope to apply a Jones Matrix algorithm, which will enable the acquisition of phase retardation from a fiber optic probe.
About Ian Rubinoff:
Ian Rubinoff is a senior at Lehigh University in the IDEAS program, studying concentrations in Electrical Engineering and Physics. For the last year, Ian has worked with Professor Chao Zhou’s research group to study optical coherence tomography and provide solutions to the obstacles faced in this field. In July of 2016, he and a fellow graduate student began construction on a fiber-based polarization sensitive optical coherence tomography system. For the last two semesters, Ian has worked to optimize the hardware and software of this system.
When he graduates this May, Ian intends on attending graduate school to continue his research with optical coherence tomography.