title: Mode-filtered large-core fiber for optical coherence tomography.
abstract: We have investigated the use of multimode fiber in optical coherence tomography (OCT) with a mode filter that selectively suppresses the power of the high-order modes (HOMs). A large-core fiber (LCF) that has a moderate number of guiding modes was found to be an attractive alternative to the conventional single-mode fiber for its large mode area and the consequentially wide Rayleigh range of the output beam if the HOMs of the LCF were efficiently filtered out by a mode filter installed in the middle. For this, a simple mode filtering scheme of a fiber-coil mode filter was developed in this study. The LCF was uniformly coiled by an optimal bend radius with a fiber winder, specially devised for making a low-loss mode filter. The feasibility of the mode-filtered LCF in OCT imaging was tested with a common-path OCT system. It has been successfully demonstrated that our mode-filtered LCF can provide a useful imaging or sensing probe without an objective lens that greatly simplifies the structure of the probing optics.
authors.affiliation: Department of Physics, Kookmin University, Seoul 136-702, South Korea.
authors.forename: Sucbei
authors.initials: S
authors.lastname: Moon
authors.forename: Zhongping
authors.initials: Z
authors.lastname: Chen
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D005240:Feasibility Studies; D005336:Fiber Optic Technology / Q000295:instrumentation*; D005374:Filtration / Q000295:instrumentation*; D008027:Light; D012542:Scattering, Radiation; D041623:Tomography, Optical Coherence / Q000295:instrumentation*