Real Defect Size Inspection for Blu-ray Discs

Blu-ray Discs (BD) release is just around the corner. Reliable inspection of local defects, which can cause playability issues, has become a major topic of discussion among replicators. The spatial data density of BDs is much higher, and track-pitches are far smaller when using a blue laser compared to DVDs, which utilize a red laser. To achieve high storage density, the numerical aperture has also been raised to 0.85, thus the pick-up head is much more sensitive to focus and tracking errors.

Based on our close relationships and collaboration with major developers of the BD format, combined with more than 20 years experience in optical design, Dr. Schenk has come up with the optimum solution for reliable quality assurance and process control throughout BD production. Instead of just an upgrade of a standard DVD scanner, a completely new optical setup, including high-speed electronics, has been developed to fulfill the special needs of BD inspection.

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