Laplace-domain diffuse optical measurement

Quantification in time-domain diffuse optical tomography using Mellin-Laplace transforms.

Simulations and phantom measurements are used to evaluate the ability of time-domain diffuse optical tomography using Mellin-Laplace transforms to quantify the absorption perturbation of centimetric objects immersed at depth 1-2 cm in turbid media. We find that the estimated absorption coefficient varies almost linearly with the absorption change in the range of 0-0.15 cm-1 but is underestimate...

Domain decomposition method for diffuse optical tomography

Diffuse optical tomography is modelled as an optimization problem to find the absorption and scattering coefficients that minimize the error between the measured photon density function and the approximated one computed using the coefficients. The problem is composed of two steps: the forward solver to compute the photon density function and its Jacobian (with respect to the coefficients), and ...

Cepstrum Domain Laplace Denoising

This paper introduces the Laplace algorithm for de-noising in the cepstrum domain with applications to speech recognition. Our method uses Gaussian mixture priors for clean speech and noise cepstra and assumes that speech and noise mix linearly in the spectrum domain. The Laplace algorithm involves two steps (a) computing the posterior mode of the observed noisy cepstra and (b) Gaussian approxi...

MEASUREMENT GUIDE OTDR - Optical Time Domain Reflectometer

Diffuse optical measurement of blood flow in breast tumors.

Blood flow contrast between tumor and normal tissues in patients with malignant and benign breast cancer was measured by diffuse optical correlation methods. The measurements were carried out with a hand-held optical probe that was manually scanned over the tumor-bearing breast. Increased blood flow was observed in tumor regions relative to healthy tissue, and control subjects did not exhibit s...