THE DETECTION OF SOFT MATERIALS BY SELECTIVE ENERGY X-RAY TRANSMISSION IMAGING AND COMPUTER-TOMOGRAPHY

Xray imaging is a well established technique of detecting strongly att enuating materials and has been applied to a number of inspection appl ications within the agricultural and food industries. However, there a re still areas within these industries in which the technique has been underexploited. In particular there are many applications within the biological sciences where we wish to detect weakly attenuating materia ls against a similar background material. It is in this area that Xray inspection techniques need to be developed. This paper seeks to show how transmission imaging could be better exploited. In particular it i s shown that the image contrast between softly attenuating materials c an be enhanced by optimally selecting the Xray energy and improving th e spatial resolution. The paper also presents full three dimensional r econstructions of samples obtained using computer tomography (CT) tech niques and discusses the potential of these methods. (C) 1997 Silsoe R esearch Institue.