Confocal light scattering spectroscopic imaging system for in situ tissue characterization.

We report on the design and construction of a confocal light scattering spectroscopic imaging system aimed ultimately to conduct depth-resolved characterization of biological tissues. The confocal sectioning ability of the system is demonstrated using a two-layer sample consisting of a 200 microm thick cancer cell layer on top of a scattering layer doped with a green absorber. The measurement results demonstrate that distinct light scattering signals can be isolated from each layer with an axial and a lateral resolution of 30 and 27 microm, respectively. Such a system is expected to have significant applications in the areas of tissue engineering and disease diagnostics and monitoring.