Measurements of heat distribution on the surface of acrylic block processed by an infrared laser have been made using an infrared thermography and an image analysis system. Thermal vectors due to laser irradiation can be derived from the temperature gradient of thermal images. Using the cross-correlation of the thermal vectors obtained in sequent two pictures, time variation of the thermal vectors has been derived which are referred to as "thermal change vectors".
Because of the use of relatively low power on acrylic block, it is possible that the heat conductive phenomenon of the processing is observed through the heat radiation ranged from 3 to 5.4 μm which can be detected with the used thermography.
This method examines the heat conductive phenomenon occurred in the acrylic surface processed by the laser to characterize the processing quality.
