We applied a polarimetric analysis to retinal imaging, to examine the potential improvement in characterizing blood vessels. To minimize the reflection artifact of the superficial wall of the blood vessel, we computed depolarized light images by removing the polarization retaining light reaching the instrument. These depolarized light images were compared to images from the average of all the light. Michelson contrast was computed for the vessel profiles across arteries and veins, and was higher for the depolarized light images. Depolarized light images provide one step towards improving the characterization of retinal blood vessels.