Aug 16 2010
Freiburg, Germany-based Fraunhofer ISE has demonstrated the LIMO diode laser system, which excites PL (photoluminescence) signals for the inspection of solar cells, on finished solar cells, as-cut wafers, and bricks. The inspected solar cells’ images were captured in less than a second.
LIMO Diode Lasers For Fast In-Line Solar Cell Inspection
The fast speed measurement allows the photoluminescence method to be utilized as an in-line process at the time of full production speed, with complete quality control. Unlike the inspection with electroluminescence, the inspection with photoluminescence offers a non-destructive and contact-less operation. This minimizes the mechanical set-up cost and the risk of solar cell damage.
The diode laser system works with one light source, unlike the other inspection tools that utilize two light sources for their operation. This feature reduces assembly costs and material count. The compact diode laser’s wavelength enables an effective separation of the signalling and excitation light than the inspection using LED illumination. Hence, the PL light detection is less complicated.