Base surface definition for morphotometry of the ear in phantoms of human heads

To assess ear thickness and other features of human heads, we defined a reference surface that interpolates the head shape in the region of interest. Laser-scan acquisitions were obtained from real human heads and processed for the construction of anthropomorphical phantoms, originally used for dosimetry studies of hand-held mobile phones. Raw data was converted to cylindrical range images and several image processing techniques were then applied for 3D-model construction. A triangulated surface was then obtained for rendering, and for CAD and finite-element simulations. The ear region was then isolated and replaced by a Coons patch surface that interpolates the skull, using the range-image information around the ear. A baseline surface was thus defined, useful for measuring features of human heads; in particular, an average thickness of the ear was estimated on 41 individuals. Head models "with" or "without" ears were then built for assessing dosimetry and anthropometry problems.