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This paper describes a carrier fringe technique for measuring surface deformation. In contrast to conventional holography and fringe analysis, this holographic system is based on the fibre optics and automatic spatial carrier fringe pattern analysis techniques. Carrier fringes are generated by simply translating the object beam between two exposures. Single-mode optic fibres are used to transfer both the object and reference beams. The use of optical fibres offers advantages in the field of optical holography. The Fast Fourier Transform (FFT) method is used to process the interferograms. This method offringe pattern analysis is a successful technique for extracting phase information from fringe patterns which result from the interference of tilted wavefronts. The paper also introduces the tile level, minimum spanning tree and phase unwrapping techniques. The method is illustrated by measuring the centrally loaded disk. A correction is made for the non uniform spacing of the carrier fringes, which was introduced by a slight inclination of object. The results are given for disk, including the perspective plot of the out of plane deformation field, the maps of wrapped and unwrapped phase, and a contour map of the unwrapped phase.

An investigation of photographic and holographic particle imaging techniques is described. Direct photographic recording has been used to obtain velocity measurements in a large scale transonic wind tunnel using Particle Image Velocimetry. Diffraction limited imaging optics were utilised to image seeding particles from 0.16 to 2.5m from the laser sheet.Particle image velocimetry data from the transonic wind tunnel and a cold burner spray were recorded onto 35mm film. It has also been shown that particle image yelocimetry data can be successfully recorded onto a CCD sensor at transonic speeds. This approach eliminates the need for photographic processing and allows real time data acquisition in a digital form.An initial investigation into the application of holographic particle imaging to a cold burner spray is also described.