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Abstract. The present work is concerned with an experimental setup for studying phase objects using multi-directional speckle photography. A mathematical description of light propagation in an optically inhomogeneous medium and a means of speckle tomography of refractive coefficient distributions are given. Recommendations on two-dimensional refractive coefficient and temperature distributions in a flame of a candle illuminated in four directions are made. The obtained results evidence that speckle photography may be a basis for tomographic studies of temperature fields in different cross-sections of an object. A speckle shift error is about 5% while the one in reconstructing local temperatures does not exceed 10%.

A new technique based on single exposure speckle photography is described that allows to measure the degree of anisotropy of turbulence in a flow with fluctuating fluid density or temperature.Since anisotropy is linked to shear in a flow, the method is also a means for discriminating regions of different shear rate.

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