Pioneer now says it can add four more layers to its Blu-ray disc

With the optical disc industry upping the ante last month, raising its goals for optical disc-based storage to a half-terabyte, Pioneer returned to testing a possible multi-layer BD, and now says it can squeeze more capacity onto one disc.

During a symposium on optical storage in Hawaii last month, Pioneer Electronics showed off its latest permutation of multi-layer recording using the DVD form factor, unveiling its draft specifications for a 16-layer Blu-ray Disc with as much as 400 GB capacity. But apparently, the company was surprised to find that the symposium had set forth a little higher goal: 500 GB by no later than 2012.

Late last week, Pioneer gave its response: essentially, "We can do that." The company is now saying it is confident it can add four additional 25 GB layers to its multi-layer specification, enabling a half-terabyte BD.

Pioneer's US patents for multi-layer optical discs date back to 1989, when the company first explained a methodology for laminating multiple layers together, each with a different band of reflectivity. When a layer does not reflect a beam, its transmissivity can be controlled to allow that beam through to the next layer.

Back in 1995, it was believed Pioneer would use its multi-layer technology to help boost the viability of an alternative version of the DVD format, developed with Toshiba and Time Warner. That version was, for a time, competing against the original DVD specification from Philips and Sony, in what was considered the most contentious format war of the time. Time Warner also held own patents for multi-layer optical discs, which included multi-sided discs that were once thought to be capable of bonding a CD-ROM layer to a DVD-ROM layer on the reverse side, and more recently, a Blu-ray layer to an HD DVD layer.