Three-dimensional polarization sensitive confocal microscopy

Abstract

We develop the technique of polarization sensitive confocal reflectance microscopy to derive three-dimensional birefringence maps of film samples. The method uses the basic confocal reflectance microscope system, but contains two arms for the separate detection of the horizontal and vertical components of the reflected signal from the sample. Using a stack of transparent adhesive tape as sample, x-y and x-z images were obtained and revealed structures that respond differently with polarization. From these confocal images, maps of the phase retardation between the two polarization components were generated even within the sample. This technique has shown that it is possible to evaluate the nature or orientation of the structures present in a birefringent sample in three dimensions. The technique may prove useful in studies concerning the evaluation of the internal structural properties of certain birefringent biological samples such as tendons and collagenous tissues.