Enhancing Infrared Images Contrast for Pulsed Thermography
نویسندگان
چکیده
In pulsed thermography the sample to test is briefly heated with a Dirac δ heat impulse and then observed through an infrared (IR) camera recording thermal images as the sample is cooling down. The difference of temperature on the IR images between the defective areas and the sound areas is referred to as a thermal contrast [1]. The Signal-to-Noise Ratio (SNR) of such a contrast is strongly affected by the non uniformity of the initial heating impulse over the specimen. This paper describes a way to enhance this SNR by comparing the temperature evolution of each pixel of the image against the temperature evolution of a heat transfer model.
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