University of Delaware researchers have been awarded a $499,430 National Science Foundation grant for innovative work to measure and develop models of elusive three-dimensional fluid surfaces using specially modified digital cameras in large arrays. The research results could find applications in fluid mechanics as well as in computer graphics and vision, providing, for example, movies and video games with more lifelike images of flowing water, according to Jingyi Yu, an assistant professor in the department of computer and information sciences and principal investigator for the project. Yu said it is difficult to get accurate information on fluid surfaces without using intrusive devices that can change their dynamics, and fluid surfaces are governed by complex physical mechanisms that need to be incorporated in reconstruction methods. Yu and co-principal investigator Philippe Guyenne, UD assistant professor of mathematical sciences, are proposing a novel approach for accurately reconstructing 3-D fluid surfaces through the design of an experimental system using a light field-camera array that can simultaneously capture different views of a fluid surface. A single photograph from a single camera enables only one point to be in focus whereas the array enables the researcher to track from foreground to background, with all points in the image in focus, Yu said. The array features from 16 to 128 digital cameras with specially modified flashes (each camera has four), lenses and apertures. Yu said it works by placing a known pattern beneath the surface, with each camera observing a distinct time-varying distortion pattern. A sampled fluid surface can then be measured by analyzing the distortions. For surface reconstruction, the researchers plan to develop an algorithm to minimize the error relative to the sampled data.