A novel load adaptive ZVS auxiliary circuit for PWM three-level dc-dc converters

10.1109/TPEL.2014.2327077IEEE Transactions on Power Electronics3042108-212

Fiber-Based Polarization Diversity Detection for Polarization-Sensitive Optical Coherence Tomography

We present a new fiber-based polarization diversity detection (PDD) scheme for polarization sensitive optical coherence tomography (PSOCT). This implementation uses a new custom miniaturized polarization-maintaining fiber coupler with single mode (SM) fiber inputs and polarization maintaining (PM) fiber outputs. The SM fiber inputs obviate matching the optical lengths of the two orthogonal OCT polarization channels prior to interference while the PM fiber outputs ensure defined orthogonal axes after interference. Advantages of this detection scheme over those with bulk optics PDD include lower cost, easier miniaturization, and more relaxed alignment and handling issues. We incorporate this PDD scheme into a galvanometer-scanned OCT system to demonstrate system calibration and PSOCT imaging of an achromatic quarter-wave plate, fingernail in vivo, and chicken breast, salmon, cow leg, and basa fish muscle samples ex vivo

Optical coherence tomography and autofluorescence imaging of human tonsil.

For the first time, we present co-registered autofluorescence imaging and optical coherence tomography (AF/OCT) of excised human palatine tonsils to evaluate the capabilities of OCT to visualize tonsil tissue components. Despite limited penetration depth, OCT can provide detailed structural information about tonsil tissue with much higher resolution than that of computed tomography, magnetic resonance imaging, and Ultrasound. Different tonsil tissue components such as epithelium, dense connective tissue, lymphoid nodules, and crypts can be visualized by OCT. The co-registered AF imaging can provide matching biochemical information. AF/OCT scans may provide a non-invasive tool for detecting tonsillar cancers and for studying the natural history of their development

AF/OCT system.

<p>AF/OCT system for imaging excised tonsils placed between glass slides, BDM: broadband dielectric mirror, DBS: dichroic beamsplitter, APD: avalanche photodiode.</p

Visualizing crypts by OCT.

<p>Middle row are enface OCT sections, top and bottom rows are OCT B-scans corresponding to the green and blue dashed lines, respectively; Cr: crypt.</p