Document Type

Theses, Masters


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Publication Details

Successfully submitted for the award of Master of Philosophy (M.Phil) to the Technological University Dublin 1999.


There are many non-destructive testing (NDT) techniques use din industry, which employ acoustic emission, ultrasound, X-rays and thermography. Optical interferometric methodology is being increasingly used in industry. Electronic Speckle Pattern Interferometry (ESPI) is one of the principal optical interferometric techniques used in NDT to measure deformations. Optical surface metrology offers many advantages over conventional methods. These include greater sensitivity, improved lateral and vertical resolution, non-contact and full field measurement. Conventional methods of NDT however continue to be chosen over ESPI. The objective of this thesis is focused on making ESPI more feasible as a NDT technique for use in industry. For this to happen the ESPI system must be inexpensive, mechanically stable in industrial environments and efficiently produce interpretable results. Using recent developments in technology a compact, portable ESPI system was developed. The system is sensitive to sub-micrometer displacements along the viewing axis of the system. The system has been used to measure surface deformations on various materials including plastic, brick, steel and aluminium


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