PNP - A New Class of Coded Aperture Arrays

We report on a new class of coded aperture arrays which has all the desirable imaging characteristics of the Uniformly Redundant Array (URA), yet is constructible in dimensions which are forbidden to that design. In addition, the new arrays (called PNP arrays, for Pseudo-Noise Product) are of self-supporting geometry, simplifying fabrication and making them ideal candidates for situations where active collimators are employed, as for example in high-energy ¿-ray imaging. A unique and important feature of all PNP arrays is the ability to produce reconstructed images whose noise is uniform regardless of the original source structure. A comparison of the predicted performance of the PNP, URA, GEOMETRIC, and PINHOLE designs is presented.