Method and apparatus for inspecting a workpiece

摘要

A computer vision apparatus and methods for automatically inspecting 2-dimensional (2D) and 3-dimensional (3D) criteria of objects using a single camera and laser sources. A camera views the object under inspection which is illuminated by a first source of light to highlight the region of interest. This provides image data for 2d analysis by a computer coupled to the system. Subsequently, multiple laser sources mounted on a positioner provide the illumination for collecting images for 3 dimensional analysis. A computer with a monitor is connected to the camera to perform the inspection and analysis and for operator supervision of the system. Specific implementations provided refer to embodiments for inspecting packaged semiconductor devices such as Ball-Grid Arrays (BGAs) packages and Quad Flat Packages (QFPs) packages for package mark inspection, package defect inspection, and solder ball or lead defects. Further, the apparatus and methods of the invention can be applied to the inspection of chip sized packages and to Flip-Chip Bump, and I.C. Die inspection. The system can also be used to inspect bond wire Wire Loop Height and to perform automated Quality Inspection for critical assembly of disk-drives, CD-Roms, keyboards, other assemblies in the computer industry and in other industries.