@article{79f755cda6ce4437854922b4d54f8a58,
title = "Fast and cost-effective in-process defect inspection for printed electronics based on coherent optical processing",
abstract = "This paper presents an all-optical difference engine (AODE) sensor for detecting the defects in printed electronics produced with roll-to-roll processes. The sensor is based on the principle of coherent optical subtraction and is able to achieve high-speed inspection by minimising data post-processing. A self-comparison inspection strategy is introduced to allow defect detection by comparing the printed features and patterns that have the same nominal dimensions. In addition, potential applications of the AODE sensor in an on-the-fly pass-or-reject production control scenario are presented. A prototype AODE sensor using a digital camera is developed and demonstrated by detecting defects on several industrial printed electrical circuitry samples. The camera can be easily replaced by a low-cost photodiode to realise high-speed all-optical information processing and inspection. The developed sensor is capable of inspecting areas of 4 mm width with a resolution of the order of several micrometres, and can be duplicated in parallel to inspect larger areas without significant cost.",
author = "Xiaobing Feng and Rong Su and Tuomas Happonen and Jian Liu and Richard Leach",
note = "Funding Information: The authors would like to acknowledge fruitful technical discussions with Prof. Jeremy Coupland (Loughborough University, UK), Dr Daniel O{\textquoteright}Connor (National Physical Laboratory, UK) and Dr Yuhang Wang (Harbin Institute of Technology, China) and thank Dr Mingyu Liu (Hong Kong Polytechnic University, China) and Mr. J{\'e}r{\'e}my Villevieille (National Engineering School of Saint-{\'E}tienne, France) for his contribution on the early experimental work. The authors also would like to thank Dr Morten Madsen, now at Topsil GlobalWafers A/S, previously at the Danish National Metrology Institute for providing the PDMS gratings. This work was supported by the Engineering and Physical Sciences Research Council [grant number EP/M008983/1] (EPSRC); and the European Metrology Programme for Innovation and Research (EMPIR) initiative [grant number 14IND09], which is co-funded by the European Union's Horizon 2020 research and innovation programme and the EMPIR participating states. Funding Information: Engineering and Physical Sciences Research Council (EPSRC) (EP/M008983/1), European Metrology Programme for Innovation and Research (EMPIR) initiative, which is co-funded by the European Union's Horizon 2020 research and innovation programme and the EMPIR participating states (14IND09). The authors would like to acknowledge fruitful technical discussions with Prof. Jeremy Coupland (Loughborough University, UK), Dr Daniel O{\textquoteright}Connor (National Physical Laboratory, UK) and Dr Yuhang Wang (Harbin Institute of Technology, China) and thank Dr Mingyu Liu (Hong Kong Polytechnic University, China) and Mr. J{\'e}r{\'e}my Villevieille (National Engineering School of Saint-{\'E}tienne, France) for his contribution on the early experimental work. The authors also would like to thank Dr Morten Madsen, now at Topsil GlobalWafers A/S, previously at the Danish National Metrology Institute for providing the PDMS gratings. This work was supported by the Engineering and Physical Sciences Research Council [grant number EP/M008983/1] (EPSRC); and the European Metrology Programme for Innovation and Research (EMPIR) initiative [grant number 14IND09], which is co-funded by the European Union's Horizon 2020 research and innovation programme and the EMPIR participating states. Funding Information: Engineering and Physical Sciences Research Council (EPSRC) (EP/M008983/1), European Metrology Programme for Innovation and Research (EMPIR) initiative, which is co-funded by the European Union's Horizon 2020 research and innovation programme and the EMPIR participating states (14IND09). Publisher Copyright: {\textcopyright} 2018 Optical Society of America. Copyright: Copyright 2018 Elsevier B.V., All rights reserved.",
year = "2018",
month = may,
day = "28",
doi = "10.1364/OE.26.013927",
language = "English",
volume = "26",
pages = "13927--13936",
journal = "Optics Express",
issn = "1094-4087",
publisher = "Optica Publishing Group",
number = "11",
}