Spatial resolution and scanning time in the optical tomography of absorbing ‘phantoms’ under multiple scattering conditions

Photon-counting optical tomography was used in the visualisation and projective reconstruction of the image of a strongly absorbing inclusion (a ‘phantom’), 6 mm in diameter, hidden by multiple scattering processes in a model object (diameter 140 mm, absorption and scattering coefficients 0.005 and 1.4 mm$^{-1}$, respectively). It was demonstrated experimentally that when the probe radiation power was 10 – 13 mW the minimal (corresponding to the poorest signal/noise ratio $\sim$ 1) measurement time (photon-counting time) was 0.8 s per one measurement point and the total time needed to scan the whole object was less than 410 s.