Visible copy protection for compact disc and digital versatile disc, is provided by boring small, deep hole in middle of surface of compact disc or digital versatile disc using thin pointed object e.g. shear

摘要

The copy protection is provided by boring a small and deep hole in the middle of a surface of compact disc or digital versatile disc using a thin pointed object e.g. shear. The hole is of approximately 0.2 millimeter.