What Is Really Inside Your AOI?

by Jean-Marc Peallat, Russ Warncke, Russell Claybrook, Marc Brun, Vi Technology Americas

Abstract: Installed for the first time 20 years ago, automated optical inspection (AOI) more recently has become an essential part of our SMT environment. Today, most process engineers are turning to machines as an inspection strategy for addressing quality and productivity issues. As the number of AOI machine manufacturers has grown, so has the array of choices, creating the difficult and confusing task of choosing one AOI machine that meets process and quality requirements.

The objective of this paper is to provide potential AOI users with guidance and better understanding of this array of choices by examining the technologies within them and shedding light upon the costs involved; including purchase, equipment operation and long-term ownership.

The first part of this article is dedicated to the “Fundamentals of AOI”, best understood by examining current inspection solutions from the perspective of the two prevailing, but different, technologies: Image Based AOI and Algorithm Based AOI. Each technology contributes a value to the inspection process that can be shown to be different. This value difference is highlighted by “key factors” (explained in more detail below), which have a clear impact on the end user’s process. These key factors also are the main considerations when calculating Return on Investment (ROI). Simplified ROI calculations are shown in this article as examples of the differences between Image and Algorithm Based AOI.

June 5, 2012