16 Layers Optical drives : The World's First 16 Layer Optical Drive from Pioneer

Pioneer announced they succeeded in developing the world’s first 16-Layer Optical Disc. This new audio-visual aid provides a storage capacity of 400 gigabytes: corresponding to 25GB per layer. Sony should introduce it at the International Symposium on Optical Memory and Optical Data Storage 2008 in Hawaii.

Photo 1: 16-layer optical disc


Photo 2: Eye-pattern signals obtained from the layers


I'll let you read the Official Press Release:

July 7, 2008, Tokyo, Japan – Pioneer Corporation has succeeded in developing a 16-layer
read-only optical disc with a capacity of 400 gigabytes for the first time in the world*1. Its
per-layer capacity is 25 gigabytes, which is the same as that of a Blu-ray Disc (BD). This
multilayer technology will also be applicable to multilayer recordable discs. This
development has bolstered Pioneer’s confidence in the feasibility of a large-capacity optical
disc, which is expected to become necessary in the near future.
For multilayer optical discs, it has been difficult to obtain clear signals from each recording
layer in a stable manner due to crosstalk from adjacent layers and transmission loss.
Utilizing the optical disc production technology that it has developed in the DVD field,
Pioneer solved these problems by, among other things, using a disc structure that can
reduce crosstalk from adjacent layers, resulting in a 16-layer optical disc that can playback
high-quality signals from every layer.
As for the read-out system, Pioneer achieved stability in the playback of recorded signals by
employing a wide-range spherical aberration compensator and light-receiving element that
can read out weak signals at a high signal-to-noise ratio in the optical pick-up mechanism.
Since the optical specifications of the objective lens, such as NA (Numerical Aperture)*2, are
the same as those for the existing BD discs, it is possible to maintain compatibility between
the new 16-layer optical disc and the BD discs.
The 16-layer optical disc technology, capable of storing much more data than the
conventional discs on one disc, will greatly reduce the number of discs to be used and
therefore contribute to the conservation of resources.
Pioneer will present the details of this research at the International Symposium on Optical
Memory and Optical Data Storage 2008 (ISOM/ODS2008 ) to be held in Hawaii from July
13.
Notes
*1: According to Pioneer survey, as of July 7, 2008.
*2: NA: The higher numerical aperture of the objective lens, the smaller diameter of the beam spot focused on a disc surface.
About Pioneer:
Pioneer Corporation, headquartered in Tokyo, is a leading global manufacturer of consumerand
business-use electronics products such as audio, video and car electronics. Its shares
are traded on the Tokyo Stock Exchange.