US Patent 7526780 Disc apparatus

A disc apparatus for recording or reading data to or from a disc includes a tray having a table on which the disc is placed and a shielding member that covers the tray. The shielding member has a circular opening and a plurality of arc protruding members. Each arc protruding member is provided on an inner surface of the shielding member that covers the tray as protruding towards an upper surface of the disc placed on the table of the tray. An end of each arc protruding member is situated near the opening. Each arc protruding member has a protruding end with a height ranging from 1.0 mm to 1.5 mm from the inner surface of the shielding member.