The invention provides a detection method for identifying the surface quality of a continuous
laser seam of a
metal workpiece online, wherein the method comprises the following steps: using a
high resolution color area array camera, a
high magnification micro lens and double LED illuminating systems to acquire an image of the surface of the seam; afterwards, when dividing a seam region and calculating the characteristic value, translating or rotating the workpiece to
shoot an image for other positions of the seam, continuously shooting the image of the seam and completing real-time calculation until reaching a
seam welding end or an overlapping point; finally integrating the calculation results of the images, and completing online judgement on the size, the position and the surface defect of the continuous seam. The method is used to complete online detection of the quality of a
laser straight welded joint, a curve
welding seam or a space
welding seam of various
ferrous metals and nonferrous metals, and belongs to the category of non-contact
visual inspection; a device is simple and compact, high in response speed and strong in anti-jamming capability, has the characteristics of stability, reliability and convenience, and can be widely applied to the field of
laser welding of
metal materials.