Image Analysis Tools to Quantify Visual Properties of Hair Fiber Assemblies 316 1. Non-laser based three-dimensional scanning is utilized in many industrial sectors to generate volumetric images. Cameras are placed around all sides of the subject and simultaneously take photographs, which are fed into a software package containing algorithms that generate a three-dimensional image. Often a projector device is mounted next to each camera and projects an image onto the subject, which provides the software with fringe projection. 2. Three-dimensional laser scanning is very similar to what we have already discussed in the subsection on three-dimensional laser stereometry. It is used for reverse engineering (e.g. automobile and aeronautic industries), material processing, entertainment industry, cosmetic surgery (breast implants, lipoinjection, etc.), apparel industry, archaelogical sites, works of art, and confocal laser scanning microscopy. Even the sacred archaeological site of Machu Picchu in Peru is currently being scanned using this technology. This technique can generate volumetric images of objects ranging in size from microns to meters. For hair care applications it could be employed to measure the volume of an entire head of hair. 3. Algorithmic modeling is used in computer animation to generate realistic three-dimensional models of hair that accurately depict shape, density, distribution, and orientation of hair strands. Equally important is hair simulation—the dynamic motion of hair and interaction of hair with other objects. To accurately depict the visual properties of hair, when computer programmers render hair they must taken into account colors, shadows, and light scattering effects. Many of the geometric principles that underlie algorithmic modeling of hair may prove useful in our understanding of hair volume. Measuring Fiber Orientation by Two-dimensional Fourier Transform Fiber alignment is a desirable trait to characterize hair fiber