In-line particle holography using photographic threshold technique

This paper describes a feasibility study of a new application of Particle Displacement Holography (PDH), which uses photographic thresholding to optically process the information in the reconstructed image. Traditionally, PDH applications have required tedious human observation of the location of the individual particle pairs. Attempts at direct digital image processing of the reconstructed image have not been successful for extending the technique to practical engineering applications. This study investigates the feasibility of a simple optical thresholding technique as a means of distinguishing the planes of focus of the individual particle pairs, and thus extracts the velocity information.