The laser ultrasound visualization imager can help user quickly identify manufacturing defects in various structures, including welded stainless steel and composites. Different from conventional ultrsound, the laser ultrasound visualization tool allows straightforward and unambiguous defect detections in those structures. Manufacturing defects, such as cracks, voids, and delaminations etc. all appear as ultrasound wave scattering centers, which can be directly visualized by playing the ultrasound propagation movies in the x-y-t dimension.