Ms. Rapaport et al., A DUAL-MODE INDUSTRIAL CT, Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 352(3), 1995, pp. 652-658
A dual-mode industrial CT system was designed and constructed, such th
at the lower and upper levels correspond to gamma-ray and X-ray CT sca
nners respectively. The gamma-ray scanner makes use of a monoenergetic
Cs-137 radioactive source and a BGO scintillator detector array emplo
yed spectroscopically. The X-ray scanner makes use of a 160 kV cp X-ra
y machine and CdWO4 scintillators operating in a current mode. The spa
tial resolution of the gamma-ray scanner is 0.6 lp/mm, and that for th
e X-ray scanner is 0.7 lp/mm. The contrast resolution is 0.5% for a vo
lume of 1 cm(3) for both scanners. The utility of the system was exami
ned on objects from the aircraft and chemical industry.