Ringed spherulites in polyethylene

Abstract

Abstract Previous authors have notes that the concentric dark rings which adorn spherulites of polyethylene under certain conditions of growth are also visible in unpolarized light. This visibility of the rings, moreover, exhibits an angular dependence when observed in phase objects which are not completely resolved by the optical microscope. Some of the light intensity in the image of the rings is considered to be lost by diffraction out of the aperture of the objective, and the experimental observations have been accounted for both qualitatively and quantitatively.