[Image analytic studies of melanin granules of human hairs with transmission electron micrographs]

Using electron micrographs of human hairs, we measured the minor axis and density of melanin granules by an image analyser. The melanin density of the outer hair cortex was higher than that of the inner hair cortex, and significant differences were evident especially in the minor axis and density of melanin granules among individuals. These quantitative analyses as to the minor axis and density of hair melanin granules are a reliable tool for the measurement of hair color.