New Product: Optics Balzers ‘SoFi’ solar filters offer correct spectral characteristics

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  Optics Balzers PVI Power Gen

Product Briefing Outline: Optics Balzers has developed interference filters satisfying customer-specific requirements. The ‘SoFi Solar Filters’ offer the correct spectral characteristics, long-term stability and accurate reproducibility even when manufactured in large volumes.

Problem: An increasing number of interference filters are being applied for quality checking and further development of solar cells. The solar cells are tested by means of sun simulators. With the aid of the new interference filters developed by Optics Balzers, the illumination spectrum of a lamp is converted so that it becomes equivalent to the solar spectrum. The nature of this spectrum is defined in a standard (IEC 60904-9) and divided into different quality classes.

Solution: According to this standard, the SoFi Solar Filters achieve not only the highest quality grade (Class A), but also produce spectra with much narrower specifications. For special sun simulator applications not covered by the standard, Optics Balzers is in a position to design and manufacture innovative filters meeting entirely different customer-specific spectral characteristic requirements. In order to split sunlight into different spectral regions, the interference filters can also be used as optically stable beam splitters which are resistant to environmental influences. Such beam splitters are applied, for example, in concentrator cells (concentrating photovoltaics), which split sun radiation and direct it to different solar cell types with optimal efficiency.

Applications: Sun simulators, concentrator cells.

Platform: The optical filter coatings manufactured by sophisticated sputter coating ensure a consistently high quality even when volume-produced and are characterized by their spectral and environmental stability.

Availability: Currently available.