Progress on large field-of-view coded aperture push-broom Compton scatter imaging

Abstract

Compton scatter imaging (CSI) is a useful nondestructive testing technique because of its flexible detection layout and high sensitivity to low-Z but high-density materials such as organics. However, previous CSI methods are limited by their low use of X-rays. Recently, we have devised a novel method called coded aperture push-broom CSI (CAPCSI) to improve the use of X-rays. In this work, we will present our progress on large field-of-view CAPCSI. A fan-beam of X-rays scans objects line-by-line and then the X-rays are scattered backward to two linear array detectors. Each detector consists of 144 scintillators, 96 Silicon photo-multipliers, and a 32-channel readout circuit array. In front of the two detectors, a mask and an anti-mask are placed individually to filter the backscattered X-rays. The coding sequences of the mask and the anti-mask are just opposite so that two complementary images could be recorded simultaneously. After averaging the two images, we finally obtain a better image for low-dose imaging.