光学检测系统的优化和评估的新方法(英文)

Optimization and Evaluation Methodfor Optical Inspection Systems

PCB厂商使用自动光学检测仪的目的是为了检测到重要的缺陷,而对于一些特殊设计和装饰性设计则不需要检测。如果要达到这一效果,就必须适当调整系统的检测参数。提供一种衡量AOI侦测性能的新颖方法。此种方法可以尽可能的减少漏测或误报产生的几率,通过考量漏测与误报的各自的成本,客户可据此结果来决定特定的机器的配备。关于自动检测设备选型机制示意图和方法,相关的实用工具及生产领域的简易实施方法也作了说明。

The value of an automated optical inspection (AOI) system for PCB manufacturers increases with its ability to detect significant, failure-causing defects, while ignoring non-significant manufacturing variations and cosmetic phenomena. But this ability can be fully realized only if the system is properly set up for the specific application being inspected. This paper presents a novel method for measuring the detection performance of the AOI system. This method points the user to the optimal setup where both missed defects (under-detection) and false alarms (over-detection) are minimized. The method takes into account the costs of a missed defect and a false alarm, such that the resulting setup is optimal for the relative cost consideration of the specific application. A discussion of the schematic mechanism of decision making in automated inspection helps to explain the theoretical foundation of the method. A practical tool that allows a simple implementation of the method on the production floor is also described.