Optical imaging of transient acoustic fields using a phase contrast method

G. T. Clement; S. V. Letcher

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arXiv · 1407.4758

Optical imaging of transient acoustic fields using a phase contrast method

G. T. Clement·S. V. Letcher

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Abstract

A coherent phase-contrast optical system has been designed and tested for tomographic imaging of pressure fields from experimental transient acoustic signals. The system is similar to the pulsed, central-order schlieren method, but uses a Fourier filtering technique that images the actual acoustic pressure field, where the former technique reconstructs only the absolute value of the field. Simulations of the system are performed using a single-cycle sine-wave acoustic pulse. Experimental images resulting from a broad-band Gaussian pulse input to an underwater piezoceramic transducer array are presented. Relative pressure field s are reconstructed in space over a series of times after the source excitation. Theory and limitations of the phase contrast system are discussed.

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G. T. Clement, S. V. Letcher. 2014-07-17. Optical imaging of transient acoustic fields using a phase contrast method. https://arxiv.org/abs/1407.4758

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