A Fast Modular RLE-Based Inspection Scheme for PCBs
Abstract
On-line inspection of PCBs requires acquisition and processing of gigabytes of image data in a matter of few seconds, especially when multi-layer and very high-resolution boards are used. To meet the demands for speed and accuracy, our inspection system uses run-length encoding (RLE) for storage and operations and an inspection scheme which exploits the availability of an artwork for comparison purposes. The system which is suitable for parallel processing consists of four parts: (i) segmentation of artwork and feature extraction, (ii) image acquisition, (iii) inspection of blank areas, and (iv) inspection of trace areas. First, the artwork which is available as a CAD file in Gerber Format, is segmented offline into primitive patterns and information related to the location and identification of each segment is stored in a large image database to be used later for real-time inspection. A time- and space-efficient technique based on RLE is used for storage of essential features and image operations.
Recommended Citation
F. Ercal et al., "A Fast Modular RLE-Based Inspection Scheme for PCBs," Proceedings of SPIE - The International Society for Optical Engineering, vol. 3203, pp. 49 - 59, Society of Photo-optical Instrumentation Engineers, Dec 1997.
The definitive version is available at https://doi.org/10.1117/12.294439
Department(s)
Computer Science
Second Department
Electrical and Computer Engineering
Keywords and Phrases
Erosion; Gerber format; Image processing; Image segmentation; Morphological operations; Printed circuit board (PCB) inspection; Run-length encoding; Space and time complexity
International Standard Serial Number (ISSN)
0277-786X
Document Type
Article - Conference proceedings
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2024 Society of Photo-optical Instrumentation Engineers, All rights reserved.
Publication Date
01 Dec 1997