Overview of Nondestructive Evaluation (NDE) Using Infrared Thermography

Abstract

Even before Max Planck published his theory of radiation on 14 December, 1900, measurement of temperature was of concern to Mankind. The first law of thermodynamics introduces the energy conservation principle and explains that any (industrial) process consuming energy will see a great part of this energy be transformed into heat (following the law of entropy). Temperature is therefore an important parameter to measure. The glass thermometer, invented by Galileo in 1593, was the first instrument for quantitative temperature measurement (Wise 1988). It allowed Herschel in 1800 to discover the infrared spectrum. Nowadays, temperatùre scale is ruled by international norms: the freezing point of gold (also known as the gold point) is the basic standard for the International Practical Temperature Scale (IPTS).