Graduate and Postdoctoral Studies
Electrical and Computer Engineering
THEORETICAL INVESTIGATION OF MATERIAL AND OPTICAL PROPERTIES AFFECTING COHERENT ANTI-STOKES RAMAN SCATTERING MICROENDOSCOPY
Monday, June 17, 2013
to 10:30 AM
Pearson Conference Room Abercrombie Engineering Laboratory
Physicians in a clinical setting are constantly seeking label-free imaging modalities with superior sensitivity and resolution. Coherent anti-Stokes Raman scattering (CARS) has demonstrated great potential to fill this need, but complicated optics and poor conversion efficiency of CARS signal photons has limited the use of endoscopic CARS. Thus, it is of utmost importance to optimize optical systems to collect the maximum possible signal for rapid, low noise endoscopic imaging. In vivo studies with CARS have collected a large backscattered signal from forward CARS, while obscuring sample features with dimensions similar to the excitation wavelength. This work models the effect of scattering in skin, lung, liver, and brain tissue on CARS imaging. By characterizing the radial location of the backward CARS signal from sub wavelength features and backscattered forward CARS signals from larger objects are collected, methods are developed to collect both images simultaneously. Numerical methods are utilized to demonstrate how the focusing objective, focal depth, collection method, and object of interest impact CARS imaging and compares to Two Photon Fluorescence (TPF) and Stimulated Raman Scattering (SRS).