Audrey K. Ellerbee

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Sound is encoded within the auditory portion of the inner ear, the cochlea, after propagating down its length as a traveling wave. For over half a century, vibratory measurements to study cochlear traveling waves have been made using invasive approaches such as laser Doppler vibrometry. Although these studies have provided critical information regarding the(More)
Spectral domain phase microscopy (SDPM) is a function extension of spectral domain optical coherence tomography. SDPM achieves exquisite levels of phase stability by employing common-path interferometry. We discuss the theory and limitations of Doppler flow imaging using SDPM, demonstrate monitoring the thermal contraction of a glass sample with nanometer(More)
We report on cross-sectional imaging of dynamic biological specimens using a spectral domain phase microscopy (SDPM) system capable of operating at a line rate of 19 kHz. This system combines the time-sensitive capabilities of SDPM with the multi-point acquisition features of related phase-sensitive techniques. The presented phase portraits and B-scan phase(More)
We present compensating methods that address inherent errors in quantitative phase reporting for low-coherence interferometric techniques. A brief theoretical treatment of the problem and experimental validation using spectral domain phase microscopy demonstrate mitigation of the degrading effects of phase leakage on accurate measurement of optical path(More)
Broadband interferometry is an attractive technique for the detection of cellular motions because it provides depth-resolved phase information via coherence gating. We present a phase-sensitive technique called spectral-domain phase microscopy (SDPM). SDPM is a functional extension of spectral-domain optical coherence tomography that allows for the(More)
This article describes a point-of-care (POC) system--comprising a microfluidic, paper-based analytical device (micro-PAD) and a hand-held optical colorimeter--for quantifying the concentration of analytes in biological fluids. The micro-PAD runs colorimetric assays, and consists of paper that has been (i) patterned to expose isolated regions of hydrophilic(More)
The development of practical strategies for the assembly of objects into 3D arrays is an unsolved problem. This paper describes the use of magnetic levitation (MagLev) to guide the self-assembly of millimeterto centimeter-scale dia magnetic objects, which we call “components”, each programmed by shape and distribution of density, into 3D assemblies and(More)
We present spectral domain phase microscopy (SDPM) as a new tool for measurements at the cellular scale. SDPM is a functional extension of spectral domain optical coherence tomography that allows for the detection of cellular motions and dynamics with nanometer-scale sensitivity in real time. Our goal was to use SDPM to investigate the mechanical properties(More)
We present a label-free, optical sensor for biomedical applications based on changes in the visible photoluminescence (PL) of quantum dots in a thin polymer film. Using glucose as the target molecule, the screening of UV excitation due to pre-absorption by the product of an enzymatic assay leads to quenching of the PL of quantum dots (QDs) in a non-contact(More)
We demonstrate the first automated, volumetric mosaicing algorithm for optical coherence tomography (OCT) that both accommodates 6-degree-of-freedom rigid transformations and implements a bundle adjustment step amenable to generating large fields of view with endoscopic and freehand imaging systems. Our mosaicing algorithm exploits the known, rigid(More)