Patent ID: 8664608
Filing Date: 2014-03-04
Classification: G01T

Abstract:
1. An apparatus comprising: a scintillator for absorbing a neutron, the scintillator having a back side for discharging a scintillation light of a first wavelength in response to the absorbed neutron; an array of wavelength-shifting fibers proximate to the back side of the scintillator for shifting the scintillation light of the first wavelength to light of a second wavelength, the wavelength-shifting fibers being disposed in a two-dimensional pattern and defining a plurality of scattering plane pixels where the wavelength-shifting fibers overlap; a plurality of photomultiplier tubes, in coded optical communication with the wavelength-shifting fibers, for converting the light of the second wavelength to an electronic signal including an electrical pulse; a series of fast comparators triggered with the electrical pulse and digitizing each detected electrical pulse into a bit stream; a high speed programmable gate array for detecting the bit stream that corresponds to the electrical pulse, for counting photons in multiple time bins that correspond to the electrical pulse, and for identifying which photomultiplier tubes generated the electronic signal including the electrical pulse; and a processor for discriminating between a gamma ray event and a neutron event based on analysis of features within a distribution of photon counts detected within each of the multiple time bins that correspond to the electrical pulse, said features including a duration of said electrical pulse and a shape of said electrical pulse, and for processing the bit stream to identify one of the plurality of scattering plane pixels as indicative of a position within the scintillator where the neutron was absorbed.