DocumentCode :
60998
Title :
Scanning Light Stimulation System With Active Focus Correction at 
Resolution for PV Applications
Author :
Bitzer, Lucas A. ; Elagin, Mikaela ; Semtsiv, Mykhaylo P. ; Masselink, W. Ted ; Benson, Niels ; Schmechel, Roland
Author_Institution :
Fac. of Eng., Univ. of Duisburg-Essen, Duisburg, Germany
Volume :
5
Issue :
2
fYear :
2015
fDate :
Mar-15
Firstpage :
627
Lastpage :
632
Abstract :
Recently, we introduced a scanning light stimulation system with an automated focus correction. The method is however resolution limited by a CMOS sensor used to focus the light beam. Here, to achieve a higher resolution, we enhanced the light beam focusing process by combining it with an edge detection technique. By this modification, the system resolution is improved down to a 1/e2 -diameter of 4.3 μm, as demonstrated using an example measurement on a multicrystalline solar cell. Furthermore, it is shown that the obtained resolution is mainly limited by height variations of the positioning system, and methods to compensate these limitations are discussed using example measurements on a quantum well solar cell.
Keywords :
OBIC; quantum well devices; solar cells; CMOS sensor; PV applications; active focus correction; edge detection technique; height variations; light beam focusing process; multicrystalline solar cell; positioning system; quantum well solar cell; scanning light stimulation system; Focusing; Laser beams; Measurement by laser beam; Optical beams; Photovoltaic cells; Surface topography; Adaptive focusing; light stimulation (LS); optical beam-induced current (OBIC); optical beam-induced voltage (OBIV); optical beams; solar cells; spatial resolution;
fLanguage :
English
Journal_Title :
Photovoltaics, IEEE Journal of
Publisher :
ieee
ISSN :
2156-3381
Type :
jour
DOI :
10.1109/JPHOTOV.2015.2392933
Filename :
7038146
Link To Document :
