Importance

Loading Importance Indicators...

Abstract

A new multi-layer optical disc structure with semi-reflective and highly reflective layers suitable for the next generation optical information storage medium is disclosed. The medium has three information layers each has about 20 Giga-bytes of storage capacity, a substrate with a thickness between 0.35 to 0.42 mm, suitable for use with a 400 to 450 nm wavelength playback laser, and a player with an objective lens with a NA between 0.65 to 0.78. New methods of making the multi-layer discs are also disclosed. A parting layer comprising a material that is relatively easy to separate from a reflective or fully semi-reflective layer is used along with polycarbonates substrates to make intermediate disc structures. The parting layer may include metal such as, for example, tin, zinc, antimony, cadmium, gallium, thallium, lead, bismuth, selenium or their mixtures. The parting layer may also include organic materials. The methods are suitable for producing multiple layer optical information storage media, for example. DVD-14, or DVD-18.

Loading the Abstract Image...

First Claim