Let the Revolution Begin

摘要

Automated optical inspection (AOI) is undergoing a revolution, and the heart of that revolution is para- metric measurement. Inspection is a form of testing that visually verifies that parts on a circuit board match expectations defined in a truth reference. In parametric inspection, expectation is a perfect model of a product, while golden-board inspection uses past examples of "acceptable" products to judge correctness. Under the parametric model, a circuit board is a set of geometric shapes related to one another. Each shape (square, rectangle, circle etc.) has a position and dimension within the set, and the entire set has a positional and orientation relative to the substrate.