Development of Calibration Target for Infrared Thermal Imaging Camera

Abstract

Camera calibration is an indispensable process for improving measurement accuracy in industry fields such as machine vision. However, existing calibration cannot be applied to the calibration of mid-wave and long-wave infrared cameras. Recently, with the growing use of infrared thermal cameras that can measure defects from thermal properties, development of an applicable calibration target has become necessary. Thus, based on heat conduction analysis using finite element analysis, we developed a calibration target that can be used with both existing visible cameras and infrared thermal cameras, by implementing optimal design conditions, with consideration of factors such as thermal conductivity and emissivity, colors and materials. We performed comparative experiments on calibration target images from infrared thermal cameras and visible cameras. The results demonstrated the effectiveness of the proposed calibration target.

Improved image processing of road pavement defect by infrared thermography

“…Sim et al (2008Sim et al ( , 2009 proposed the application of a black coating on the surface of the specimen to minimize the effect of the superficial emissivity during the application of thermography combined together with an image processing algorithm using the Gauss filter and the Prewitt mask for the damaged zone of the defect [7,8]. Recently, Kim et al (2014) developed a calibration target for infrared thermal imaging camera using finite element heat transfer analysis in the domain of visual inspection technology so as to increase the accuracy of the geometrical data of the image [3]. Other researchers also exploited image processing to measure the area in specimens made of composite materials [10].…”