Smart-skin structures for identifying and locating laser irradiation

摘要

Abstract: We have developed a mathematical model of a technique in which a pyramidal arrangement of wavelength-selective optical detectors can be used to determine the identity (wavelength), intensity, and direction of arrival of laser irradiation. The advantages of this technique are that only unobtrusive, skin-like structures are required and that the large collection areas provide high sensitivity. The disadvantage is that the angular resolution (approximately 5 degrees in a 60 degree field of view) is less than that which can be achieved using methods requiring thicker structures. The detector elements are large-area, polyvinylidine fluoride, pyroelectric devices with wavelength selective coatings. We situated four identical arrays of these elements on the top and sides of a frustrated, three-sided prism. Because only the relative orientations are significant, we are able to use selected regions on the surface of an existing structure in an application of this work. Our efforts included developing the mathematical description of the system and, using coated detectors whose performance was experimentally verified, modeling the response to in-channel, monochromatic radiation. Although we limited our model to a simple, two-channel system, the concept and algorithm can easily be extended to a system of any reasonable number of nonoverlapping channels. !2