We present Fermat single pixel camera for visible to SWIR biomedical imaging by encoding the spatial coordinate of the diffuse reflectance into different temporal modulation frequencies. The recovered reflectance spatial profile was then used to characterize the optical parameters of the specimen. The results from measurement on optical phantoms and biological tissues suggest Fermat single pixel camera can successfully quantify the optical properties over the visible to SWIR spectral range and may find valuable applications in imaging without a conventional camera.
We present a spatial frequency domain imaging (SFDI) study of local hemodynamics in the human finger cuticle of healthy volunteers performing paced breathing and the forearm of healthy young adults performing normal breathing with our recently developed Real Time Single Snapshot Multiple Frequency Demodulation – Spatial Frequency Domain Imaging (SSMD-SFDI) system. A two-layer model was used to map the concentrations of deoxy-, oxy-hemoglobin, melanin, epidermal thickness and scattering properties at the subsurface of the forearm and the finger cuticle. The oscillations of the concentrations of deoxy- and oxy-hemoglobin at the subsurface of the finger cuticle and forearm induced by paced breathing and normal breathing, respectively, were found to be close to out-of-phase, attributed to the dominance of the blood flow modulation by paced breathing or heartbeat. Our results suggest that the real time SFDI platform may serve as one effective imaging modality for microcirculation monitoring.
We present a spatial frequency domain imaging (SFDI) study of local hemodynamics in the forearm of healthy volunteers performing paced breathing. Real time Single Snapshot Multiple Frequency Demodulation - Spatial Frequency Domain Imaging (SSMD-SFDI) was used to map the optical properties of the subsurface of the forearm continuously. The oscillations of the concentrations of deoxy- and oxyhemoglobin at the subsurface of the forearm induced by paced breathing are found to be close to out-of-phase, attributed to the dominance of the blood flow modulation by paced breathing. The properties of local microcirculation including the blood transit times through capillaries and venules are extracted by fitting to Simplified Hemodynamics Model. Our preliminary results suggest that the real time SSMD-SFDI platform may serve as one effective imaging modality for microcirculation monitoring.
We present here the numeric study of the propagation of polarized coherent complex light in turbid media with Electric field Monte Carlo (EMC) approach. EMC is one unique Monte Carlo method suitable for simulating coherent phenomenon of multiple scattering light. EMC has been extended to explicitly incorporate the complex incident wave front of coherent complex light and used to investigate the interaction of coherent complex light with highly scattering turbid media such as biological tissue. We will report the dependence of the decay of the beam intensity and the loss of the polarization over the penetration depth on the orbital angular momentum of the complex light and the scattering properties of a turbid medium. The potential application of complex light in imaging turbid media will be discussed.