Quantification of the porosity of membranes by digital images analysis techniques

A digital image processing method was developed to calculate the porosity, pore size distribution, pore area orientation from the SEM images of membrane surface. After image trimming the SEM images are transformed to the binary images to get the pores which formed by fibers. The pores of the membrane were considered as ellipse which should fit the pore properly. Then the porosity such as the total pore percentage, the pores number, and the mean pore diameter could be derived from the obtained binary images. The samples with different magnification were tested using this image processing method and the test results were further compared.