동적 세그먼트 기반 PCB 패턴의 적응 검사 알고리즘

다국어 초록 (Multilingual Abstract)

Several methods for PCB pattern inspection have been tried to detect tine defects in pad contours, but their low detection accuracy results from pattern variations originating from etching, printing and handling processes. The adaptive inspection algorithm has been newly proposed to extract minute defects based on movable segments. With gerber master images of PCB, vertex extractions of a pad boundary are made and then a lot of segments are constructed in master data. The pad boundary is composed of segment units. The proposed method moves these segments to optimal directions of a pad boundary and so adaptively matches segments to pad contours of inspected images, irrespectively of various pattern variations. It makes a fast, accurate and reliable inspection of PCB patterns. Its performances are also evaluated with several images.

참고문헌 (Reference)

1 _, "한국정밀공학회지" 2006

2 _, "접수일: 2005년9월20일; 게재승인일: 2006년 2월 10일" 2006

3 "따라서 검사자의 주관적인 해석으로 불량의 유무를 판단하기에는 다소 애매한 부분이라고 판단된다."

4 "그 중 Protrusion 과검출은 패드들이 너무 밀접하게 있는 경우에 발생하였다. 이것은 패드간의 간격 정보를 저장하여 이를 활용함으로써 처리가 가능하겠지만 검사 시간의 지연을 초래할 것으로 예상된다. 다른 한 가지 유형인 Nick은 패드의 곡률이 큰 부분에서 발생하였다. 이것은 에칭 공정으로 인해 곡률이 큰 부분에 나타나는 경우로써 검사자의 주관적인 판단기 준에 따라 Nick결점으로 볼 수도 있고 과검출로 판단할 수도 있는 경우이다."

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