Coded aperture imaging application in one-sided imaging of visually obscured objects

Abstract

The physical properties of visible light and its interaction with matter create obstructions the human eye cannot explore. High energy radiation has been used as an alternative to visible light to penetrate these concealed regions and reveal their contents. However, traditional imaging techniques require a two-sided apparatus with a radiation source and a detector on opposite sides of the concealed object. One-sided imaging of concealed objects is made possible by a technique called backscatter imaging, utilizing high energy radiation. However, the signal produced by backscatter imaging is inherently weak, which makes in- terpretation di cult. One of the most promising techniques for recovering the weak signal is the coding and decoding provided by Coded Aperture Imaging (CAI). The purpose of this study was to create and test a coded aperture imaging system using backscattered x-rays. This would enable one-sided imaging of concealed objects and demonstrate whether a portable imaging system was feasible. The results obtained from conducting a computer simulation, visi- ble light experiments, and x-ray experiments proved that the process works, however, the x-ray ux levels required were too high for a portable system, based upon the current equipment available at UOIT.