Patent ID: 7785689
Filing Date: 2010-08-31
Classification: G11B

Abstract:
1. An optical data storage medium comprising: a first thermoplastic polycarbonate substrate defining a first side and a second side; and a second thermoplastic polycarbonate substrate defining a first side and a second side, wherein the first side of the first thermoplastic polycarbonate substrate is incident to a laser when the medium is read through the first thermoplastic polycarbonate substrate, the second side of the first thermoplastic polycarbonate substrate defines an information bearing surface that is read through the first thermoplastic polycarbonate substrate, and the second side of the second thermoplastic polycarbonate substrate includes one or more substantial void areas wherein the substantial void areas are configured such that approximately ten to eighty-five percent of a volume of the second thermoplastic polycarbonate substrate is removed relative to a substrate that defines flat parallel surfaces without the void areas.