Defect inspection system and defect inspection method

Abstract

Images of a face surface and a back surface of a plywoodthat is conveyed on belt conveyorsU andD are captured by imaging devices of first illumination and imaging unitsF andB to generate depth information, a shape of the plywoodis measured by shape measurement unitsF andB, which are provided at locations different from a location of a gapwhere the image capturing is performed, to generate shape information, and the depth information is corrected based on the shape information, and then a defect in the plywoodis detected based on the depth information. By detecting a defect in the plywoodbased on the depth information corrected using the shape information that is measured without being affected by vibrations that occur when the plywoodis conveyed over the gap, a defect such as warpage or bending can be accurately detected without deformation occurring in the plywoodbeing flattened by the correction of the depth information.