Observation of a phase object using a multipinhole camera

Publisher Website
Google Scholar
Abstract
This method of observation of a phase object makes use of the extremely high demagnification and the large image densities involved in the multiple-imaging effect obtained with a multipinhole camera. The multipinhole camera consists of an array of circular microapertures equally spaced in the x and y directions. A coarse self-diffusing grid is multiply imaged by the multipinhole camera. If appropriate conditions exist among the magnification factor, dimensions, period of the coarse grid, and equidistance of the circular microapertures, the ensemble of multiple fine images of the coarse grid would function like a single fine grating. The fine grating is photographed through a phase object which produces deformations on the grating lines. The superposition of the straight grating lines and the deformed ones on the photographic plate give rise to a moire pattern which characterizes the phase variations of the object.