The new YIELDMASTER PL classifies the material structures according to their physical construction and ensures high throughputs. Thus critical cracks or process deviations and non-critical grain boundaries in multi-crystalline cells are differentiated reliably. In addition to that, the PL inspection technology does not require any electrical contacts on the cell, which reduces the mechanical stress and allows cell inspection at any stage along the production process. For the user this means a contactless inline detection of micro cracks, breaks, Czochralski growth defects, electrical wafer quality, distribution of minority carrier lifetimes, inactive areas, low efficient dark regions, scratches, dislocations, circular marks, finger interruptions and firing defects. Such a system enables cell manufacturers to improve the quality control of the basic material leading to a significant increase in high-quality yield as the company states. The new system reduces the false rejects by a factor of minimum 6, increases maximum quality output by at least 3% and reduces the cycle by more than three times.