An efficient low-cost calibration board for Long-wave infrared (LWIR) camera

The process of geometric camera calibration for long-wave infrared (LWIR) camera is essential for determining the camera's intrinsic and extrinsic parameters, which maps 3D world coordinate points onto 2D image coordinate points. In this paper, new calibration board materials are proposed for making a plane checkerboard to calibrate the LWIR camera. These materials are low-cost items and, to the best of our knowledge, has not been used so far for calibration of infrared camera. The resulting calibration board exhibited high thermal infrared image contrast and showed consistent checkerboard corners' detection to accomplish the geometric calibration of LWIR wavebands camera. The suggested method is tested using three different LWIR cameras in an indoor environment. The quality of new proposed board thermal imaging is compared with existing calibration board made by paint. The calibration approach is experimented using "MATLAB Single Camera Calibrator Tool" for each of the three LWIR cameras and showed that the overall calibration mean reprojection error is less than 0.35 pixel. The proposed calibration board is beneficial in terms of precision, low- cost built-up and easy reusability.