@inproceedings{49265e6a60144c48bebbe7bbae53d568,
title = "In-situ defect detection systems for R2R flexible PV barrier films",
abstract = "Film processing procedures by means of Roll-to-Roll (R2R) for barrier coatings can often result in PV barrier films being manufactured with significant quantities of defects, which results in lower efficiency and a short life span. In order to improve the process yield and product efficiency, it is desirable to develop an inspection system that can detect transparent barrier film defects in the production line during film processing. Off-line detection of defects in transparent PV barrier films is difficult and time consuming. Consequently, implementing an accurate in-situ defects inspection system in the production environment is even more challenging, since the requirements on positioning, fast measurement, long term stability and robustness against environmental disturbance are demanding. This paper reports on the development and deployment of two in-situ PV barrier films defect detection systems, one based on wavelength scanning interferometry (WSI) and the other on White Light Channeled Spectral Interferometry (WLCSI), and the integration into an R2R film processing line at the Centre for Process Innovation (CPI). The paper outlines the environmental vibration strategy for both systems, and the developed auto-focusing methodology for WSI. The systems have been tested and characterised and initial results compared to laboratory-based instrumentation are presented.",
keywords = "Defects, Interferometry, Photovoltaic and Aluminum Oxide, Surface inspection, Thin-film",
author = "F. Gao and H. Muhamedsalih and D. Tang and Mohamed Elrawemi and L. Blunt and X. Jiang and S. Edge and D. Bird and P. Hollis",
year = "2015",
month = aug,
day = "5",
doi = "10.1117/12.2193140",
language = "English",
isbn = "9781628418033",
volume = "9622",
series = "Proceedings of SPIE - The International Society for Optical Engineering",
publisher = "SPIE",
editor = "Guangming Shi and Xuelong Li and Bormin Huang",
booktitle = "2015 International Conference on Optical Instruments and Technology",
address = "United States",
note = "International Conference on Optical Instruments and Technology 2015 ; Conference date: 17-05-2015 Through 19-05-2015",
}