Maximising the signal-to-noise ratio in computerised tomography data using robust design
1996 (English)In: Insight (Northampton), ISSN 1354-2575, Vol. 38, no 2, 112-117 p.Article in journal (Refereed) Published
Image quality in Computerised Tomography (CT) depends strongly on the quality of the CT-projection data, which vary with the imaged sample and the equipment used. The objective has been to find a setting of the CT-scanner Control Factors (CF) maximising the signal-to-noise ratio in CT projection data (SNRCT) of a contrasting detail (for example a defect) and a surrounding cylindrical sample, and to present a general optimisation methodology. An optimisation case study was carried out, valid for a CT-scanner equipped with a polyenergetic X-ray source (conventional) with tungsten target and a partially energy-integrating detector system (image intensifier and optical video chain), with and without consideration qf the exposure limits associated with the microfocal X-ray source used. The CF of interest were tube potential, exposure (product of tube current and exposure time), material and thickness of the primary filter, optical aperture and attenuation equalising filter design. The settings yielding the highest values of SNRCT were found using thick filter of high atomic number, small iris and use of an X-ray attenuation equalisation filter design. The exposure limits make the CF interdependent, yielding another optimal setting. The CF setting was also found to be independent of the contrasting detail, in the particular case study.
Place, publisher, year, edition, pages
1996. Vol. 38, no 2, 112-117 p.
Non destructive test ; Tomography ; Signal to noise ratio ; Image quality ; Scanner ; Signal analysis ; X ray
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-13566OAI: oai:DiVA.org:liu-13566DiVA: diva2:20966