title: Needle-based refractive index measurement using low-coherence interferometry.
abstract: We present a novel needle-based device for the measurement of refractive index and scattering using low-coherence interferometry. Coupled to the sample arm of an optical coherence tomography system, the device detects the scattering response of, and optical path length through, a sample residing in a fixed-width channel. We report use of the device to make near-infrared measurements of tissues and materials with known optical properties. The device could be used to exploit the refractive index variations of tissue for medical and biological diagnostics accessible by needle insertion.
authors.affiliation: Biophotonics Imaging Laboratory, Department of Electrical and Computer Engineering, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
authors.forename: Adam M
authors.initials: AM
authors.lastname: Zysk
authors.forename: Steven G
authors.initials: SG
authors.lastname: Adie
authors.forename: Julian J
authors.initials: JJ
authors.lastname: Armstrong
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Leigh
authors.forename: Alexandre
authors.initials: A
authors.lastname: Paduch
authors.forename: David D
authors.initials: DD
authors.lastname: Sampson
authors.forename: Freddy T
authors.initials: FT
authors.lastname: Nguyen
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Boppart
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000295:instrumentation*; D007089:Image Enhancement / Q000295:instrumentation*; D007368:Interferometry / Q000295:instrumentation* / Q000379:methods; D009339:Needles; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence / Q000295:instrumentation* / Q000379:methods; D014159:Transducers