LOCALIZATION OF LUMINESCENT INHOMOGENEITIES IN TURBID MEDIA WITH SPATIALLY-RESOLVED MEASUREMENTS OF CW DIFFUSE LUMINESCENCE EMITTANCE

We present a steady-state method for localizing a source of luminescen ce (i.e., fluorescence or phosphorescence) buried in a semi-infinite t urbid medium with unknown optical properties. A diffusion theory expre ssion describing the emittance of an isotropic point source is fit to spatially resolved surface measurements of the diffuse emittance from the luminescent source. The technique reports the location of the cent er of a 6.0-mm-diameter, fluorophore-containing spherical bulb embedde d in a liquid phantom with an accuracy of 1.0 mm or better for source depths as great as 40.0 mm. Monte Carlo data are analyzed to investiga te the range and the possible sources of error in the reconstructed so urce depth. (C) 1998 Optical Society of America.