LASER WELDING QUALITY EVALUATION METHOD AND ITS DEVICE

摘要

A difference processing circuit 22 receives input of welding images taken by a CCD camera 8 in real time and then differentiates power monitoring images recorded in a memory 21 from welding images to obtain difference processing reflected light images. Due to the difference processing performed by a difference processing circuit 22, foreign matter images included in welding images and power monitoring images are eliminated and the difference processing reflected light images that are obtained do not include any foreign matter images. A quality judgment device 17 uses the difference processing reflected light images obtained by a difference processing circuit 22 and conducts a quality judgment. As described above, since difference processing reflected light images do not include any foreign matter images, a quality judgment device 17 does not receive any influence from the foreign matter that is adhered to the protective glass 15 and can conduct an excellent evaluation of the welding quality.