Development and applications of a gamma-ray tomographic scanner.

Abstract

Computerised Tomography (CT) is now an established technique in medicine, but has yet to see any widespread applications in industry, partly because of the high cost of medical machines. This thesis examines the requirements and limitations of a gamma-ray tomographic scanner for industrial and research applications. The basic theory of CT reconstruction is outlined, together with a description of how this has been practically realised by means of a stepping motor controlled table that accurately positions the sample within a fixed radiation beam. Several features of the scanner are described in detail; namely the development of the isotope sources and their associated collimators, and the microcomputer control. The performance is analysed and many possible applications are discussed, accompanied by examples derived from the scanner. It has been shown that worthwhile results can be obtained with only a modest amount of equipment. Some suggestions for improvements are made, many of which may be implemented in a future programme of work