Why does the Four-Layer disc only have 128GB capacity? Why didn’t the capacity double again?

The capacity per layer is different in the Single Layer/Dual Layer, Triple Layer and Quadruple Layer formats:

	Single Layer	Dual Layer	Triple Layer	Quadruple Layer
Total Capacity	25GB	50GB	100GB	128GB
Capacity per Layer	25GB		33.4GB	32GB
Minimum Mark Width	.149 µm		.112 µm	.117 µm

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Polyline has triple-layer, 100GB, recordable BDXL discs in stock and ready to
ship. Want to learn more? Visit http://www.PolylineCorp.com/Line1/.

Can my current recorder/player read/write the BDXL format?

Legacy Blu-ray devices cannot read the new BDXL format. The BDA created a new BDXL logo to distinguish the new BDXL media and devices from the legacy machines. If your device does not have the new BDXL logo, than it is a legacy machine.


It is not mandatory, but a new device supporting BDXL discs can be easily designed to support the 15GB/50GB discs. So the new specs say that it’s possible that new BDXL machines can read/write to older discs, but it’s not required.

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Polyline has triple-layer, 100GB, recordable BDXL discs in stock and ready to
ship. Want to learn more? Visit http://www.PolylineCorp.com/Line1/.

What is BDXL?

BDXL is a multi-layer recordable Blu-ray disc format with up to 128GB capacity. In April 2010, the Blu-ray Disc Association (BDA) created specifications for triple-layer, 100GB Recordable and Rewritable discs and a quadruple-layer, 128GB for Recordable disc. Both the triple-layer and quadruple-layer formats can be called BDXL.

The high capacity format is being targeted at commercial segments such as broadcasting, medical and document imaging enterprises with significant archiving needs. The BDXL format was created as a long-term and stable solution for archiving large amounts of sensitive data, video and graphic images.
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Polyline has triple-layer, 100GB, recordable BDXL discs in stock and ready to
ship. Want to learn more? Visit http://www.polylinecorp.com/productlist.asp?OPT=line-1-media-bdxl-100gb.