Cognex's Checker is said to be the first and only vision sensor in the world that uses patterns to detect parts and provides output pulses that are synchronized with part position. During operation, it continually watches for trained patterns to appear. After detecting a part, it evaluates the object multiple times from different perspectives, thus offering the possibility of more reliable timing results than with photoelectric sensors. It also reportedly detects features that photoelectric sensors can't, offers fewer false "accepts," offers fewer false rejects, and calls for less tweaking. Cognex says it can be used to check for the presence of O-rings, to verify presence of date/lot codes, to examine package assemblies, look for paint dots, analyze threads on automotive parts, and serve in dozens of other applications. For more information, go to http:// rbi.ims.ca/4922-507.