Estimation of filler macro‐dispersion in rubber matrix by radiometric stereo microscopy
Optical Microscopy has long been the preferred method for rapid dispersion analysis because of its relative simplicity. Reflective Light Microscopy with automatic image processing has become a standard tool for evaluating filler dispersion of agglomerates in the micron range, and is often referred to as macro dispersion. Many researchers, however, recognize the need to study particles and aggregates in the nano-scale, and have therefore used more costly and complicated methods such as Atomic Force Microscopy, and Electron Microscopy. Optical microscopy’s shortcomings in ultra-high resolution measurements are due to the electromagnetic diffraction limit, which confines resolution of white light to approximately one micron. In this work a new reflected light method which provides resolution of less than one micron is discussed. The method avoids the diffraction limit of visible light by mechanically moving a sample in small increments.