Abstract Proposal Number: CTS-9714345 Principal Investigator: Milgram This project is aimed at developing methods to digitize 2D holograms (pieces of exposed and developed photographic film) and reconstruction of the 3D optical fields by digital computation. This has the potential to make analysis of data on holograms not only faster, but better controlled since each step in the computational processing is precise. The usual method of obtaining quantitative data in the form of a computer file from a hologram is to reconstruct the optical field in a laboratory and scan that field in three dimensions with a tracking video camera having microscope optics. This is an extremely tedious process in as much as the hologram must be illuminated with a special laser system to reconstruct the optical field encrypted on the hologram and the amount of 3D data which then has to be scanned is usually enormous. Although the detailed project work is on development of computer algorithms and on digitizing holograms, the motivation comes from applications in fluid mechanics and in marine biology. For example, three dimensional particle image velocity achieved by making a double or triple exposure hologram of particles in a volume (HPIV) is a brand new and developing method. In addition, a potentially revolutionary extension of the project is direct digital recording of measurement holograms with the extended resolution laboratory scale video cameras of the near future.
