Light intensity distributions in refracting structures placed between crossed polarizers.

A number of refracting structures each with different optical properties, were placed between crossed polarizers, illuminated with diffuse light and photographed. The images of the characteristic cross pattern (isogyres) seen in such structures, viewed under these conditions, were analysed to determine the relative distributions of light intensity within the patterns. The experimental findings show that intensity distributions are related to the optical properties of a refracting structure. Comparison of dimensional differences shows that in a larger sample the profile of light intensity distribution (in the quadrants between the isogyres) is more symmetrical and the peak is closer to the centre of the quadrant. Sharper peaks are seen in the intensity distribution profiles of gradient-index structures than in profiles of homogenous-index bodies of comparable dimensions. Some agreement was found between an experimental observation and a previously derived mathematical model for homogenous index, curved bodies.