Affiliation:
1. National Physical Laboratory, Teddington, Middlesex
Abstract
Holography is a novel method of photography using coherent light from a laser source. Its unique feature is that it records a faithful three-dimensional image of the object. This allows one to compare the shape of an engineering component at one moment in time with its shape after some change has taken place, e.g. by deforming it under load. In some cases the holographic image of a ‘master’ component can be used as a template against which similar components can be matched with high precision. The techniques of holography, the interpretation of the results obtained, and the present limitations of the method will be discussed.