A scattering microscope was developed to investigate single cells and biological microstructures by light scattering measurements. The spectrally resolved part of the setup and its validation are shown in detail. The analysis of light scattered by homogenous polystyrene spheres allows the determination of their diameters using Mie theory. The diameters of 150 single polystyrene spheres were determined by the spectrally resolved scattering microscope. In comparison, the same polystyrene suspension stock was investigated by a collimated transmission setup. Mean diameters and standard deviations of the size distribution were evaluated by both methods with a statistical error of less than 1nm. The systematic errors of both devices are in agreement within the measurement accuracy.
Keywords: (180.0180) Microscopy; (290.1350) Back scattering; (290.2200) Extinction; (290.4020) Mie theory; (290.5850) Scattering, particles; (300.6550) Spectroscopy, visible.