Double pulse infrared thermography

Abstract In this paper we propose a simple enhancing protocol for pulsed infrared thermography. The method is based on stimulating the specimen with two heating pulses separated by a short time interval delta. This approach was tested on several specimens of low and high thermal diffusivity and showed to provide higher thermal contrasts when an optimum interval delta is chosen. The observed thermal contrast improvement is about a few percentage values. Lastly, a Matlab™ procedure is also proposed to link this interval to the thermal diffusivity of the specimen. In the paper, the method is presented including theoretical basis, simulation and experimental results.

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