Pioneer Corp has developed a read-only optical disc that realizes a storage capacity of 400 Gbytes by recording data on 16 layers. Each of the layers has a 25-Gbyte capacity, which corresponds to the capacity of a Blu-ray Disc.
As optical specifications of the objective lens including the NA (numerical aperture) are the same as those of the existing Blu-ray Disc, Pioneer can maintain the new disc's compatibility with the Blu-ray Disc, it said.
Generally, multilayer optical discs are facing challenges concerning difficulty in receiving clear signals from each recording layer and noises due to crosstalk from layers other than the one being replayed, for example. This time, Pioneer developed a structure that can reduce noises from adjacent recording layers, it said.
As for the read-out system, the company adopted an optical device that corrects a wide range of aberration and light-receiving element that can read out weak signals at a high S/N (signal-to-noise) ratio. Through these efforts, Pioneer realized stable read-out of signals.
The company developed a read-only disc this time, but the technology can be applied to recordable discs as well, it said. Pioneer will advance its research and development toward the realization of a large capacity optical disc that makes a large-volume archive come true.
Pioneer will present the details of this research at the "International Symposium on Optical Memory and Optical Data Storage 2008 (ISOM/ODS2008)," which will take place in Hawaii from July 13 to 17, 2008.