Lijun Zhuo , Changhu Liu , Jun Zhou , Jianguo Zhu , Chaoyi Li , Antonio Fernández López
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引用次数: 0
Abstract
The thickness of the optically translucent coating was evaluated using the transmission thermography. The transmitted temperature of a two-layer structure was theoretically analysed based on the equation of 1D heat transfer in the depth direction, and accordingly, the method for the measurement of coating thickness in a two-layer structure was established based on a long-pulse transmission thermography. The coating thickness was determined based on the characteristic time at the maximum half-rise temperature. Then, the proposed method was experimentally validated and calibrated by coating specimen with a different coating thickness. The thickness measurement method was further applied to measure an uneven coating specimen fabricated by mechanical grinding. The measurements were compared with a 3D digital image correlation method and the averaged relative error was less than 4%. Finally, thermal excitation, sampling rate of thermography and translucence of organic coating were discussed for accurate measurement.
期刊介绍:
The Journal covers the entire field of infrared physics and technology: theory, experiment, application, devices and instrumentation. Infrared'' is defined as covering the near, mid and far infrared (terahertz) regions from 0.75um (750nm) to 1mm (300GHz.) Submissions in the 300GHz to 100GHz region may be accepted at the editors discretion if their content is relevant to shorter wavelengths. Submissions must be primarily concerned with and directly relevant to this spectral region.
Its core topics can be summarized as the generation, propagation and detection, of infrared radiation; the associated optics, materials and devices; and its use in all fields of science, industry, engineering and medicine.
Infrared techniques occur in many different fields, notably spectroscopy and interferometry; material characterization and processing; atmospheric physics, astronomy and space research. Scientific aspects include lasers, quantum optics, quantum electronics, image processing and semiconductor physics. Some important applications are medical diagnostics and treatment, industrial inspection and environmental monitoring.