Computerized image analysis of dielectric breakdown phenomena in polyethylene

Improvements in sample preparation methods are very important to the analysis of all the dielectric breakdown phenomena present in polyethylene insulated cables. Computerized image analysis affords a method of automatically scanning a sample to count trees, voids, and inclusions. This method is absolute whereas most other methods currently used rely on the measurement of small numbers of samples. Tree size distributions have been found to be very heavily weighted in the size range of 1 µm to 10 µm. This size range is commonly ignored with presently used staining and observation methods.