Holographic contouring using double-source technique and Fourier transform analysis

This paper describes a double-exposure holographic contouring technique by the movement of the object beam through fibre optics. Single-mode optic fibres are used to transfer both object and reference beams. Between two exposures the object illumination beam is displaced. The contouring fringes can be visualised on the object surfaces. The fringe patterns are automatically processed by the fast Fourier transform (FFT) method, which produces a 3D perspective plot. Examples are given for different objects.