Bliss_Bedrich - 2018 IEEE JPV - EL Img of PV devices.pdf (1.16 MB)
Electroluminescence imaging of PV devices: Advanced vignetting calibration
journal contribution
posted on 2018-08-24, 10:29 authored by Karl G. Bedrich, Matevz Bokalic, Martin BlissMartin Bliss, Marko Topic, Tom BettsTom Betts, Ralph GottschalgIEEE Electroluminescence (EL) imaging is affected by off-axis illumination together with sensor and lens imperfections. The images’ spatial intensity distribution is mainly determined by the vignetting effect. For quantitative EL imaging, its correction is essential. If neglected, intensities can vary significantly (>50%) across the image. This paper introduces and tests four vignetting measurement methods. The quantitative comparison of different methods shows that vignetting should be characterized preferably in plane by the source of the same type as the photovoltaic (PV) device to be tested. A direct PV-based measurement in short distance with spatial inhomogeneity correction is proposed for general-purpose vignetting characterization. For precise vignetting characterization, vignetting-object separation using pattern recognition is proposed. The use of non-PV light sources for vignetting characterization can cause vignetting overcorrection and can even decrease the quality of the vignetting-corrected images.
History
School
- Mechanical, Electrical and Manufacturing Engineering
Published in
IEEE Journal of PhotovoltaicsVolume
8Issue
5Pages
1297 - 1304Citation
BEDRICH, K.G. ... et al., 2018. Electroluminescence imaging of PV devices: Advanced vignetting calibration. IEEE Journal of Photovoltaics, 8(5), pp. 1297-1304.Publisher
© IEEEVersion
- AM (Accepted Manuscript)
Acceptance date
2018-06-14Publication date
2018-07-10Notes
Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.ISSN
2156-3381eISSN
2156-3403Publisher version
Language
- en